WO2025226030A1 - Method for colliding frozen composition particles having size capable of penetrating skin with skin and system for performing same - Google Patents

Abstract

The present disclosure relates to a method for colliding frozen composition particles having a size capable of penetrating the skin with the skin, and a device for performing same. Specifically, the present invention relates to a cryogenic spraying method and a device for performing same, in which a composition is frozen to generate solid frozen particles, and the generated solid frozen particles are collided with the skin to induce penetration of the composition, for the purpose of allowing the composition to pass through the stratum corneum of the skin.

Description

Method for colliding frozen composition particles having a size capable of penetrating the skin with the skin and system for performing the same

The present disclosure relates to a method for impacting skin with frozen composition particles having a size capable of penetrating the skin, and a system for performing the same. Specifically, the present disclosure relates to a freeze spray method for generating solid frozen particles by freezing a composition, with the goal of allowing the composition to penetrate the stratum corneum of the skin, and a system for performing the same, by impacting the generated solid frozen particles onto the skin to induce penetration of the composition.

When delivering a composition to the skin, the degree of penetration of the composition into the skin has a significant impact on the degree of efficacy achieved. Accordingly, various studies have been conducted to improve the composition's penetration into the skin.

Methods for delivering the composition to the skin include applying the composition to the skin, injecting the composition into the skin, or spraying the composition onto the skin.

Among these, it is known that the method of applying the composition to the skin has difficulty in penetrating the lipid layer of the skin depending on the molecular weight and biochemical properties of the composition, and thus only a very small amount is absorbed into the skin.

Furthermore, while it's possible to deeply penetrate the composition into the skin using an injection, it inevitably causes damage to the skin. This can lead to not only pain during the procedure, but also bruising and swelling due to the damage. Furthermore, the process of injecting the composition into the skin requires considerable skill on the part of the practitioner, which can lead to variations in the depth and amount of penetration depending on the practitioner, resulting in inconsistent effects.

Accordingly, there is a need for a method of delivering a composition that ensures the composition's penetration into the skin and induces a consistent penetration effect while minimizing damage to the skin.

The challenge to be solved is to get the composition to reach the depth below the stratum corneum of the skin.

The challenge is to get the composition to break down and penetrate the stratum corneum of the skin.

The challenge to be solved is to create composition freeze particles having a size that allows penetration.

The task to be solved is to impinge the skin with frozen particles of a composition of a size that allows penetration.

The task to be solved is to spray a liquid composition, but freeze the composition during the spraying process to create frozen particles of a size that allows penetration.

The challenge to be addressed is to achieve a desired penetration depth of the composition relative to the skin surface.

The challenge to be solved is to achieve a target penetration depth of the composition relative to the skin surface, regardless of the composition's viscosity.

The problems to be solved are not limited to the problems described above, and problems not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

According to one embodiment, a freeze spray system for delivering a composition into the skin by freezing and spraying the composition is provided, comprising a coolant spray device and a composition guide, wherein the composition guide guides a liquid composition to a position adjacent to a nozzle of the coolant spray device so that the liquid composition meets a coolant sprayed from the coolant spray device, and the coolant spray device sprays a coolant toward a supply end of the composition guide from which the liquid composition flows, so that the liquid composition is atomized into a plurality of liquid atomized particles by the sprayed coolant and some of the plurality of liquid atomized particles are cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, wherein some of the plurality of solid frozen particles have a particle size capable of penetrating a stratum corneum of the skin before colliding with the skin and reach the inside of the skin.

The means of solving the problem are not limited to the above-described means of solving the problem, and means of solving the problem that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

In one embodiment, the composition can reach a depth below the stratum corneum of the skin.

In one embodiment, the frozen composition particles impinging on the skin surface may have a penetrable size.

In one embodiment, the composition can reach a target depth relative to the surface of the skin.

In one embodiment, the composition can reach a target depth relative to the surface of the skin regardless of the viscosity of the composition.

The effects of the invention are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

Figure 1 is a drawing showing the path through which the composition can pass through the stratum corneum of the skin.

FIG. 2 is a drawing showing frozen composition particles that are the target of particle size measurement according to one embodiment.

FIG. 3 is a drawing showing a method for measuring particle size according to one embodiment.

Figure 4 is a drawing showing the results of the first experiment to confirm the skin penetration effect of frozen composition particles and the particle size and velocity of the frozen composition particles in the first experiment.

Figure 5 is a drawing showing the results of a second experiment to confirm the skin penetration effect of frozen composition particles and the particle size and velocity of the frozen composition particles in the second experiment.

Figure 6 is a schematic diagram showing a freeze spray system according to one embodiment.

FIG. 7 is a diagram showing a process of atomizing and freezing a pre-atomized liquid composition according to one embodiment.

FIG. 8 is a drawing showing a freeze spray system according to one embodiment.

FIG. 9 is a drawing showing the configurations of a coolant injection device according to one embodiment.

Fig. 10 is a drawing showing a composition providing device according to one embodiment.

Fig. 11 is a drawing showing a composition providing device according to another embodiment.

Fig. 12 is a flowchart showing a freeze spraying method according to one embodiment.

Figure 13 is a drawing showing the distance between the nozzle and the supply end according to one embodiment.

Figure 14 is a drawing showing the sharpness of the supply end according to one embodiment.

Fig. 15 is a flowchart showing a device design method of a freeze injection system according to one embodiment.

Fig. 16 is a flowchart showing a control design method of a freeze injection system according to one embodiment.

FIG. 17 is a diagram showing the results of an experiment on the relationship between the viscosity and penetration depth of a composition according to one embodiment.

Fig. 18 is a flowchart showing a method for controlling penetration depth considering target penetration depth and composition viscosity according to one embodiment.

According to one embodiment, a freeze spray system for delivering a composition into the skin by freezing and spraying the composition is provided, comprising a coolant spray device and a composition guide, wherein the composition guide guides a liquid composition to a position adjacent to a nozzle of the coolant spray device so that the liquid composition meets a coolant sprayed from the coolant spray device, and the coolant spray device sprays a coolant toward a supply end of the composition guide from which the liquid composition flows, so that the liquid composition is atomized into a plurality of liquid atomized particles by the sprayed coolant and some of the plurality of liquid atomized particles are cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, wherein some of the plurality of solid frozen particles have a particle size capable of penetrating a stratum corneum of the skin before colliding with the skin and reach the inside of the skin.

The nozzle has an orifice having a preset diameter, and a coolant spray stream is formed as the coolant passes through the orifice, and the liquid composition formed at the supply end of the composition guide is separated from the supply end by the coolant spray stream and introduced into the coolant spray stream in the form of particles.

The particle sizes of the plurality of solid frozen particles are determined according to the horizontal distance and vertical distance between the orifice of the nozzle and the supply end, wherein the horizontal distance is the distance between the orifice and the supply end in a direction parallel to the central axis of the nozzle, and the vertical distance is the distance between the orifice and the supply end in a direction perpendicular to the central axis of the nozzle.

The smaller the horizontal distance, the smaller the particle size of the plurality of solid frozen particles, and the smaller the vertical distance, the smaller the particle size of the plurality of solid frozen particles.

The cross-section of the supply end of the above composition guide has a sharp shape whose width becomes narrower toward one side, and the greater the degree to which the width of the cross-section becomes narrower, the greater the sharpness of the supply end, and the particle size of the plurality of solid frozen particles is determined according to the sharpness of the supply end.

The above supply terminal is characterized in that the larger the sharpness, the smaller the size of the plurality of solid frozen particles.

As the sharpness of the supply end increases, the size of the plurality of liquid atomized particles decreases, and the particle size of the plurality of solid frozen particles decreases.

The cross-section of the above supply end includes two line segments forming a preset angle, and the smaller the preset angle, the smaller the particle size of the plurality of solid frozen particles.

The above freezing injection system further includes a composition storage section in which the liquid composition is stored; and a composition transfer pipe fluidly connecting the composition guide and the composition storage section; wherein the liquid composition is transferred from the composition storage section to the composition guide through the composition transfer pipe.

The above freezing spray system further includes an actuator connected to the composition storage unit to control the flow rate of the liquid composition; and the particle sizes of the plurality of solid frozen particles are determined according to the composition flow rate controlled by the actuator.

The above coolant injection device further includes a coolant heating module configured to heat the coolant before the coolant is injected; wherein the particle size of the plurality of solid frozen particles is determined according to the degree to which the coolant heating module heats the coolant.

When the coolant heating module is controlled to heat the coolant at a first heating amount per unit time, the particle sizes of the plurality of solid frozen particles have a smaller value than when the coolant heating module is controlled to heat the coolant at a second heating amount per unit time that is greater than the first heating amount per unit time.

The above freezing injection system further includes a coolant container in which the coolant supplied to the coolant injection device is stored, and the particle size of the plurality of solid frozen particles is determined according to the internal pressure of the coolant container.

The smaller the internal pressure, the larger the particle size of the plurality of solid frozen particles.

The particle size of the above plurality of solid frozen particles is 16 μm to 42 μm.

The particle size of the above plurality of solid frozen particles is 10 μm to 80 μm.

According to another embodiment, a freezing spray system for delivering a composition to the skin is provided, comprising: a coolant spray device for spraying a coolant; and a composition guide for supplying a liquid composition to the sprayed coolant; wherein a portion of the liquid composition supplied by the composition guide is atomized into a plurality of liquid particles by the coolant sprayed from the coolant spray device, and a portion of the plurality of liquid atomized particles are cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, wherein the plurality of solid frozen particles include penetrable frozen particles that penetrate the surface of the skin, and the penetrable frozen particles have a particle size of 16 μm to 42 μm and a spray speed of 75 m/s to 110 m/s at a position spaced apart from the coolant spray device by 10 mm to 14 mm in the coolant spraying direction.

The above coolant injection device includes a nozzle through which the coolant is injected, and the particle sizes of the plurality of solid frozen particles are determined according to a horizontal distance and a vertical distance between an orifice of the nozzle and a supply end of the composition guide, wherein the horizontal distance is a distance between the orifice and the supply end in a direction parallel to the central axis of the nozzle, and the vertical distance is a distance between the orifice and the supply end in a direction perpendicular to the central axis of the nozzle.

The smaller the horizontal distance, the smaller the particle size of the plurality of solid frozen particles.

The smaller the vertical distance, the smaller the particle size of the plurality of solid frozen particles.

The particle size of the plurality of solid frozen particles is determined according to the sharpness of the supply end of the above composition guide.

The sharper the supply end, the smaller the particle size of the plurality of solid frozen particles.

The cross-section of the supply end of the above composition guide includes two line segments forming a preset angle, and the particle sizes of the plurality of solid frozen particles are determined according to the preset angle.

The smaller the preset angle, the smaller the particle size of the plurality of solid frozen particles.

The above coolant injection device further includes a coolant heating module configured to heat the coolant before the coolant is injected; wherein the particle size of the plurality of solid frozen particles is determined according to the degree to which the coolant heating module heats the coolant.

When the coolant heating module is controlled to heat the coolant with a first heating amount per unit time, the particle sizes of the plurality of solid frozen particles have a smaller value than when the coolant heating module is controlled to heat the coolant with a second heating amount greater than the first heating amount per unit time.

The device further includes a coolant container in which the coolant supplied to the coolant injection device is stored, and the particle size of the plurality of solid frozen particles is determined according to the internal pressure of the coolant container.

The smaller the internal pressure, the larger the particle size of the plurality of solid frozen particles.

According to another embodiment, a composition freeze spray method for delivering a composition to the skin by freezing the composition and causing it to collide with the surface of the skin is provided, comprising: preparing a freeze spray system including a coolant spraying device for spraying a coolant and a composition guide for supplying a liquid-state composition to the sprayed coolant; when the freeze spray system is driven, the liquid-state composition supplied by the composition guide is atomized into a plurality of liquid particles by the coolant sprayed from the coolant spraying device, and some of the plurality of liquid atomized particles are cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, each of the plurality of solid frozen particles having a specific particle size and a specific spraying speed; and using the freeze spray system, causing solid frozen particles having a particle size of 16 μm or more and 42 μm or less to collide with the surface of the skin at a spraying speed of 75 m/s or more and 110 m/s or less so as to penetrate the surface of the skin.

The above coolant injection device includes a nozzle through which the coolant is injected, and the particle sizes of the plurality of solid frozen particles are determined according to a horizontal distance and a vertical distance between an orifice of the nozzle and a supply end of the composition guide, wherein the horizontal distance is a distance between the orifice and the supply end in a direction parallel to the central axis of the nozzle, and the vertical distance is a distance between the orifice and the supply end in a direction perpendicular to the central axis of the nozzle.

The smaller the horizontal distance, the smaller the particle size of the plurality of solid frozen particles.

The smaller the vertical distance, the smaller the particle size of the plurality of solid frozen particles.

The particle size of the plurality of solid frozen particles is determined according to the sharpness of the supply end of the above composition guide.

The sharper the supply end, the smaller the particle size of the plurality of solid frozen particles.

The cross-section of the supply end of the above composition guide includes two line segments forming a preset angle, and the particle sizes of the plurality of solid frozen particles are determined according to the preset angle.

The smaller the preset angle, the smaller the particle size of the plurality of solid frozen particles.

The above coolant injection device further includes a coolant heating module configured to heat the coolant before the coolant is injected; wherein the particle size of the plurality of solid frozen particles is determined according to the degree to which the coolant heating module heats the coolant.

When the coolant heating module is controlled to heat the coolant with a first heating amount per unit time, the particle sizes of the plurality of solid frozen particles have a smaller value than when the coolant heating module is controlled to heat the coolant with a second heating amount greater than the first heating amount per unit time.

The above freezing injection system further includes a coolant container in which the coolant supplied to the coolant injection device is stored, and the particle size of the plurality of solid frozen particles is determined according to the internal pressure of the coolant container.

The smaller the internal pressure, the larger the particle size of the plurality of solid frozen particles.

According to another embodiment, a freezing spray system for delivering a composition to the skin is provided, comprising: a coolant spray device for spraying a coolant; and a composition guide for supplying a liquid composition to the sprayed coolant; wherein a portion of the liquid composition supplied by the composition guide is atomized into a plurality of liquid particles by the coolant sprayed from the coolant spray device, and a portion of the plurality of liquid atomized particles is cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, wherein the plurality of solid frozen particles include penetrable frozen particles that penetrate the surface of the skin, and the penetrable frozen particles have a particle size of 10 μm to 80 μm and a spray speed of 16 m/s to 48 m/s at a position spaced apart from the coolant spray device by 10 mm to 14 mm in the coolant spraying direction.

According to another embodiment, a composition freeze spray method for delivering a composition to the skin by freezing the composition and causing it to collide with the surface of the skin is provided, comprising: preparing a freeze spray system including a coolant spraying device for spraying a coolant and a composition guide for supplying a liquid-state composition to the sprayed coolant; when the freeze spray system is driven, the liquid-state composition supplied by the composition guide is atomized into a plurality of liquid particles by the coolant sprayed from the coolant spraying device, and some of the plurality of liquid atomized particles are cooled by the sprayed coolant and frozen into a plurality of solid frozen particles, each of the plurality of solid frozen particles having a specific particle size and a specific spraying speed; and using the freeze spraying system, causing solid frozen particles having a particle size of 10 μm or more and 80 μm or less to collide with the surface of the skin at a spraying speed of 16 m/s or more and 48 m/s or less so as to penetrate the surface of the skin.

According to another embodiment, a freezing spray system for delivering a composition below a certain range of depths from a skin surface comprises: a cooling agent spraying device for spraying a cooling agent, the cooling agent spraying device including a cooling agent heating module configured to heat the cooling agent before the cooling agent is sprayed; a composition guide for supplying a liquid composition to the sprayed cooling agent, the liquid composition being atomized and cooled by the sprayed cooling agent to be frozen into a plurality of solid frozen particles, wherein a particle size range of the plurality of solid frozen particles is determined according to a viscosity of the liquid composition, and a spraying speed range of the plurality of solid frozen particles is determined according to a heating amount per unit time of the cooling agent heating module; an input unit for receiving an input regarding a viscosity of the composition from a user; And a control module for controlling the coolant heating module based on a value received from the input unit; wherein the control module controls the coolant heating module according to a first control method when a first composition viscosity is received through the input unit so that the plurality of solid freezing particles reach a depth below the specific range from the skin surface, and controls the coolant heating module according to a second control method when a second composition viscosity smaller than the first composition viscosity is received through the input unit, wherein the heating amount per unit time of the coolant heating module controlled according to the first control method has a value smaller than the heating amount per unit time of the coolant heating module controlled according to the second control method.

The higher the viscosity of the liquid composition, the larger the particle size of the plurality of solid frozen particles and the greater the depth to which the plurality of solid frozen particles reach from the skin surface.

As the heating amount per unit time of the coolant heating module decreases, the spraying speed of the plurality of solid frozen particles decreases and the depth to which the plurality of solid frozen particles reach from the skin surface decreases.

The above coolant injection device further includes a coolant container in which the coolant is stored and a pressure adjuster for controlling the pressure of the coolant container, and the control module controls the pressure adjuster according to the viscosity of the composition received.

When the first composition viscosity is received, the pressure of the coolant container controlled by the pressure regulator has a value lower than the pressure of the coolant container controlled by the pressure regulator when the second composition viscosity is received.

According to another embodiment, a freezing spray system for delivering a composition below a certain range of depths from a skin surface comprises: a cooling agent spraying device for spraying a cooling agent, the cooling agent spraying device including a cooling agent heating module configured to heat the cooling agent before the cooling agent is sprayed; a composition guide for supplying a liquid composition to the sprayed cooling agent, the liquid composition being atomized and cooled by the sprayed cooling agent to be frozen into a plurality of solid frozen particles, wherein a particle size range of the plurality of solid frozen particles is determined according to a viscosity of the liquid composition, and a spraying speed range of the plurality of solid frozen particles is determined according to a heating amount per unit time of the cooling agent heating module; a sensor module for measuring a viscosity of the liquid composition; And a control module for controlling the coolant heating module based on the value measured by the sensor module; wherein the control module controls the coolant heating module according to a first control method when a first composition viscosity is measured through the sensor module so that the plurality of solid freezing particles reach a depth below the specific range from the skin surface, and controls the coolant heating module according to a second control method when a second composition viscosity smaller than the first composition viscosity is measured through the sensor module, wherein the heating amount per unit time of the coolant heating module controlled according to the first control method has a value smaller than the heating amount per unit time of the coolant heating module controlled according to the second control method.

The higher the viscosity of the liquid composition, the larger the particle size of the plurality of solid frozen particles and the greater the depth to which the plurality of solid frozen particles reach from the skin surface.

As the heating amount per unit time of the coolant heating module decreases, the spraying speed of the plurality of solid frozen particles decreases and the depth to which the plurality of solid frozen particles reach from the skin surface decreases.

The above coolant injection device further includes a coolant container in which the coolant is stored and a pressure adjuster for controlling the pressure of the coolant container, and the control module controls the pressure adjuster according to the viscosity of the composition received.

When the first composition viscosity is received, the pressure of the coolant container controlled by the pressure regulator has a value lower than the pressure of the coolant container controlled by the pressure regulator when the second composition viscosity is received.

According to another embodiment, a freezing spray system for delivering a composition below a certain range of depth from a skin surface comprises: a cooling agent spraying device for spraying a cooling agent, the cooling agent spraying device including a cooling agent container in which the cooling agent is stored and a pressure adjuster for controlling a pressure of the cooling agent container; a composition guide for supplying a liquid composition to the sprayed cooling agent, the liquid composition being atomized and cooled by the sprayed cooling agent to be frozen into a plurality of solid frozen particles, wherein a particle size range of the plurality of solid frozen particles is determined according to a viscosity of the liquid composition, and a spraying speed range of the plurality of solid frozen particles is determined according to a pressure of the cooling agent container; an input unit for receiving an input regarding a viscosity of the composition from a user; And a control module for controlling the coolant pressure regulator based on a value received from the input unit; wherein the control module controls the pressure regulator according to a first control method when a first composition viscosity is received through the input unit so that the plurality of solid freezing particles reach a depth below the specific range from the skin surface, and controls the pressure regulator according to a second control method when a second composition viscosity smaller than the first composition viscosity is received through the input unit, wherein when the pressure regulator is controlled according to the first control method, the pressure of the coolant container has a value smaller than the pressure of the coolant container when the pressure regulator is controlled according to the second control method.

According to another embodiment, a freezing spray system for delivering a composition below a certain range of depth from a skin surface comprises: a cooling agent spraying device for spraying a cooling agent, the cooling agent spraying device including a cooling agent container in which the cooling agent is stored and a pressure adjuster for controlling a pressure of the cooling agent container; a composition guide for supplying a liquid composition to the sprayed cooling agent, the liquid composition being atomized and cooled by the sprayed cooling agent to be frozen into a plurality of solid frozen particles, wherein a particle size range of the plurality of solid frozen particles is determined according to a viscosity of the liquid composition, and a spraying speed range of the plurality of solid frozen particles is determined according to a pressure of the cooling agent container; a sensor module for measuring a viscosity of the liquid composition; And a control module for controlling the pressure regulator based on the value measured by the sensor module; wherein the control module controls the pressure regulator according to a first control method when a first composition viscosity is measured through the sensor module so that the plurality of solid freezing particles reach a depth below the specific range from the skin surface, and controls the pressure regulator according to a second control method when a second composition viscosity smaller than the first composition viscosity is measured through the sensor module, wherein when the pressure regulator is controlled according to the first control method, the pressure of the coolant container has a value smaller than the pressure of the coolant container when the pressure regulator is controlled according to the second control method.

The above-described purposes, features, and advantages will become more apparent through the following detailed description taken in conjunction with the accompanying drawings. However, the present invention is susceptible to various modifications and various embodiments. Therefore, specific embodiments will be illustrated in the drawings and described in detail below.

In the drawings, the thicknesses of layers and regions are exaggerated for clarity, and when an element or layer is referred to as "on" or "on" another element or layer, this includes not only the case where the element or layer is directly above the other element or layer, but also the case where another layer or other element is interposed. In principle, the same reference numerals represent the same elements throughout the specification. In addition, elements that have the same function within the scope of the same idea shown in the drawings of each embodiment are described using the same reference numerals, and redundant descriptions thereof will be omitted.

The numbers used in the description of this specification (e.g., first, second, etc.) are merely identifiers to distinguish one component from another.

In addition, the suffixes "module" and "part" for components used in the following examples are given or used interchangeably only for the convenience of writing the specification, and do not have distinct meanings or roles in themselves.

In the examples below, singular expressions include plural expressions unless the context clearly indicates otherwise.

In the following examples, terms such as “include” or “have” mean that a feature or component described in the specification is present, and do not preclude the possibility that one or more other features or components may be added.

For convenience of explanation, the sizes of components in the drawings may be exaggerated or reduced. For example, the sizes and thicknesses of each component shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to what is shown.

In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

In the following examples, when it is said that a film, region, component, etc. are connected, it includes not only cases where the films, regions, and components are directly connected, but also cases where other films, regions, and components are interposed between the films, regions, and components and are indirectly connected.

For example, when it is said in this specification that a film, region, component, etc. are electrically connected, it includes not only cases where the film, region, component, etc. are directly electrically connected, but also cases where another film, region, component, etc. is interposed and indirectly electrically connected.

In the following examples, the meaning that a membrane, region, component, etc. are fluidly connected can be interpreted to mean that the membrane, region, component, etc. each form at least a portion of a flow path through which a fluid flows.

For example, in this specification, the fact that component A is fluidly connected to component B may mean that a fluid passing through a path formed by component A can reach a path formed by component B, or vice versa. Specifically, if components A and B are combined such that the path formed by component A and the path formed by component B are directly connected, components A and B may be considered to be fluidly connected. Alternatively, if components A and B are connected through component C, such as a conduit, such that the path formed by component A and the path formed by component B are indirectly connected through the path formed by component C, components A and B may be considered to be fluidly connected. In this case, component C may be interpreted as fluidly connecting components A and B. Furthermore, it goes without saying that components A and B may be fluidly connected through a plurality of components.

Unless specifically stated or clear from context, the term "about" in relation to a numerical value shall be understood to mean the numerical value stated plus or minus 10% of that numerical value, and the term "about" in relation to a numerical range shall be understood to mean a range from 10% below the lower limit of the numerical range to 10% above the upper limit of the numerical range.

1. Overview

The present disclosure relates to a method for impacting skin with frozen composition particles having a size capable of penetrating the skin, and a system for performing the same. Specifically, the present disclosure relates to a freeze spray method for generating solid frozen particles by freezing a composition, with the goal of allowing the composition to penetrate the stratum corneum of the skin, and a system for performing the same, by impacting the generated solid frozen particles onto the skin to induce penetration of the composition.

The composition may include an active substance that induces or produces a medical effect. Alternatively, the composition may include an active substance that induces or produces a cosmetic effect.

Furthermore, the composition in the present disclosure is particularly characterized by being delivered transdermally, and the composition may refer to a substance that produces a cosmetic effect or a medical effect when delivered transdermally.

The composition may, for example, contain minerals, nucleic acids, amino acids, coenzymes, vitamins, niacinamide, oil-soluble licorice extract, arbutin, hyaluronic acid, potassium hyaluronate, hydrolyzed hyaluronic acid, hydrolyzed sodium hyaluronate, hydroxypropyltrimonium hyaluronate, sodium acetylated hyaluronate, sodium hyaluronate crosspolymer, sodium hyaluronate, retinol, retinyl palmitate, It may include adenosine, peptide, coenzyme Q10, adult stem cell, antioxidant, poly-d-lactic acid (PDLA), polynucleotide, polydeoxyribonucleotide (PDRN), poly-d,l-lactic acid (PDLLA), lidocaine, botulinum toxin, exosome, proparacaine, tetracaine, human growth hormone, growth factor, cell therapy products, or a combination thereof.

Furthermore, the composition may further include base ingredients such as purified water, glycerin, butylene glycol, propanediol, and silicone oil; formulation forming ingredients such as emulsifiers, surfactants, and viscosity modifiers; and preservative ingredients such as parabens, phenoxyethanol, benzoic acid, triclosan, benzyl alcohol, methylisothiazolinone, and 1,2-hexanediol.

This disclosure describes a method of spraying a composition using a delivery medium. For example, the composition can be transported by a coolant sprayed at a relatively high velocity and sprayed onto a target area. In this case, the composition's temperature can be lowered by the coolant sprayed at a relatively low temperature.

Here, the coolant may be liquefied carbon dioxide (CO2), carbon dioxide, liquefied nitrogen, liquefied oxygen, nitrogen dioxide (NO2), nitrogen monoxide (NO), nitrous oxide (N2O), a hydrofluorocarbon (HFC) series substance, methane (CH4), perfluorocarbon (PFC), sulfur hexafluoride (SF6), or a combination thereof, and a substance capable of applying cooling energy to a target area, such as coolant or a cooling gas, may be used. Meanwhile, in addition to the coolant, compressed air, etc. may also be used.

For convenience of explanation, the following description describes the composition as being transported by a refrigerant, and liquefied carbon dioxide is used as the refrigerant, but the technical idea of the present disclosure is not limited thereto.

Freezing a composition means that a liquid or gaseous composition changes to a solid state due to a decrease in temperature. When the temperature is lowered, the composition becomes a solid composition with crystals. The freeze spraying method described in this disclosure can be understood as a method of freezing a liquid composition and spraying it so that the solid composition is sprayed onto a target area.

In the present disclosure, the "target area" refers to the area to which the composition is to be sprayed. Specifically, the target area may refer to the skin surface of a portion of the human body. Alternatively, the target area may refer to the skin surface of a portion of the body of an animal other than a human. The target area may be determined based on the body part to which the composition is to be applied.

The freeze spraying method described in this disclosure has various usage patterns as follows.

Freezing spraying can be used as a treatment method or medical procedure. In this context, the composition refers to a drug or medicine, and can be understood to include substances used for the diagnosis, cure, alleviation, treatment, or prevention of diseases or conditions, skin regeneration, lifting, and treatment of acne, inflammation, and other skin problems.

A doctor, etc. (a medical professional defined by the medical laws of each country as a person with medical expertise) can use the freezing spray method to spray a composition that has a therapeutic effect on a specific disease or illness on the subject.

The freeze-jet method can be used as a cosmetic method, cosmetic procedure, or skin care. In this case, the composition can be understood as a cosmetic product that, when applied to the skin, contains substances that induce cosmetic effects such as whitening, skin soothing, nourishing, moisturizing, wrinkle improvement, or elasticity improvement. Furthermore, the composition can be composed of substances with little or no effect on the human body.

An esthetician or skin care professional can spray a composition having a cosmetic effect on a patient using a freezing spray method.

The freeze-jet method can be used as a therapeutic or cosmetic method for animals other than humans. In this case, the composition may be understood to contain an active substance, such as a drug, medicine, or cosmetic product, that has a therapeutic or cosmetic effect.

The freezing spray method described in this disclosure has the main purpose of penetrating the composition into the skin.

Penetration of a composition means that the composition reaches a certain depth relative to the skin surface.

Referring to Figure 1, the skin is divided into the epidermis and the dermis, and the epidermis is composed of the stratum corneum, the transparent stratum, the stratum granulosum, the stratum spinosum, and the stratum basale. Here, the stratum corneum of the epidermis performs a skin barrier function and is the main factor that hinders the absorption of the composition.

Therefore, penetration of the composition means that the composition reaches at least below the stratum corneum. Since the thickness of the stratum corneum is generally about 10 um to about 20 um, penetration of the composition means reaching a depth of about 0.01 mm or more from the skin surface.

For example, if the subject to whom the composition is to be provided is the face of a Korean adult, the epidermis is distributed to a depth of about 0.1 mm from the skin surface, and the dermis is distributed to a depth of about 0.1 mm to about 2 mm from the skin surface.

The penetration of the composition into the face is about 0.01 mm to 2 mm deep, about 0.02 mm to 2 mm deep, about 0.1 mm to 2 mm deep, about 0.2 mm to 2 mm deep, about 0.3 mm to 2 mm deep, about 0.4 mm to 2 mm deep, about 0.5 mm to 2 mm deep, about 0.6 mm to 2 mm deep, about 0.7 mm to 2 mm deep, about 0.8 mm to 2 mm deep, about 0.9 mm to 2 mm deep, about 1 mm to 2 mm deep, about 1.1 mm to 2 mm deep, about 1.2 mm to 2 mm deep, about 1.3 mm to 2 mm deep, about 1.4 mm to 2 mm deep, about 1.5 mm to 2 mm deep, Depth means that the composition reaches a depth of about 1.6 mm to about 2 mm, a depth of about 1.7 mm to about 2 mm, a depth of about 1.8 mm to about 2 mm, or a depth of about 1.9 mm to about 2 mm. Since the thickness of the epidermis and dermis may vary depending on the area within the face, the reference depth defining the penetration of the composition is not limited to the aforementioned values.

Meanwhile, the target for spraying the composition is not limited to the face. Other body parts, such as the scalp, neck, arms, legs, hands, and feet, can also be targeted. In this case, penetration of the composition means reaching beneath the stratum corneum or the epidermis in each area.

For a composition to achieve its intended purpose (e.g., inducing therapeutic or cosmetic effects), it must be absorbed into the skin. For a composition to be absorbed, it must penetrate beyond the stratum corneum and diffuse into the spinous layer, basal layer, or dermis. In other words, even if a composition contains highly effective ingredients, if it remains in the stratum corneum, its effectiveness will inevitably be minimal.

One method for permeating a composition into the skin involves spraying the liquid composition onto the skin. This spraying method involves spraying the liquid composition onto the skin through a nozzle or similar device, causing the liquid particles, which possess kinetic energy, to collide with the skin surface and reach the skin's interior.

At this time, as illustrated in Fig. 1, the sprayed composition must pass through the stratum corneum of the skin surface in order to penetrate into the skin. The method by which the composition penetrates the dermis through the epidermis of the skin is largely divided into three types. Referring to Fig. 1, the composition passes through the transcellular route (a) directly through the stratum corneum of the epidermis, the intercellular route (b) through the nonpolar lipid layer between keratinocytes, and the trans-appendageal route (c) through appendages such as pores.

Here, since the liquid composition particles are not solid, it is difficult for them to utilize the transcellular pathway that penetrates the keratinocytes, and the intercellular pathway is also densely packed with keratinocytes surrounded by lipid membranes, making it difficult for the liquid composition to pass through. Ultimately, most liquid compositions can penetrate through the appendage passage pathway, but since the appendages account for less than 0.1% of the skin surface area, the amount of composition that can be penetrated is limited.

The applicant expected that if the composition is in a solid state rather than a liquid state when colliding with the skin surface, the force with which the composition hits the skin surface will be maximized, so that the composition can penetrate the skin by breaking the stratum corneum through physical impact, regardless of the aforementioned transcellular pathway, intercellular pathway, and accessory organ passage pathway. The applicant conceived the idea of freezing the composition as a method of making the composition into a solid state, and accordingly, developed a freezing spray method for freezing the composition while spraying it, as described below, and a freezing spray device capable of freezing a liquid composition while spraying it.

Meanwhile, the applicant conducted an experiment in which frozen particles (frozen composition particles) of a solid-state composition were sprayed onto the skin using a freeze spray method. However, there were cases in which the composition penetrated the skin and cases in which it did not, and cases in which the size of the frozen particles was relatively small and cases in which the size of the frozen particles was relatively large.

The applicant recognized that when a composition is frozen and sprayed, penetration may be determined depending on the size of the frozen particles, and the reason for this was estimated as follows.

First, in order for the composition frozen particles to destroy and penetrate the stratum corneum (i.e., to penetrate through the transcellular pathway), the collision energy against the stratum corneum must be sufficiently large, and the collision energy is proportional to the mass of the frozen particles (i.e., proportional to the particle size) and the collision velocity.

Meanwhile, as the particle size of the frozen particles increases, their mass increases in proportion to the cube of the particle size, resulting in greater collision energy against the stratum corneum. Furthermore, since the resistance of the stratum corneum is proportional to the square of the particle size, the degree to which the collision energy increases with larger particles exceeds the degree to which the resistance of the stratum corneum increases. Therefore, it can be predicted that larger frozen particles will more easily penetrate the stratum corneum; however, it may be difficult to penetrate the stratum corneum for the following reasons.

First, the larger the particle size of the frozen particles, the more likely they are to break upon impact with the stratum corneum, thereby losing force (speed) toward the skin, making penetration difficult.

The reason why the possibility of breaking increases is that i) the larger the particle size, the greater the collision energy received by the frozen particle when colliding with the stratum corneum of the skin, ii) the more internal defects such as micro-cracks or pores inside the frozen particle, the less solidity there is compared to the frozen particle with a small particle size, so when colliding with the skin, the collision energy is concentrated in the cracks, making the frozen particle more likely to break, and iii) the surface area of the frozen particle is large, so when colliding, the collision energy is not applied to the entire surface of the frozen particle, but rather locally, so the specific part where the collision energy is concentrated can break more easily.

Second, the larger the particle size of the frozen particles, the greater the kinetic energy required to accelerate the frozen particles. Therefore, if the force that accelerates the frozen particles (e.g., the flow rate of the coolant spray stream described below) is constant, the larger the particle size, the less likely it is that the collision speed of the frozen particles will reach the critical value for penetrating the skin. In other words, the frozen particles may not be sufficiently accelerated, making penetration into the stratum corneum difficult.

As mentioned above, the larger the particle size, the greater the collision energy, which may facilitate the destruction of the stratum corneum. However, the larger the particle size, the higher the probability of particle breakage, and the resistance received by the stratum corneum is greater than the collision energy of the frozen particles that have been broken and reduced in size, making penetration difficult, or acceleration by a medium that accelerates the frozen particles, such as a coolant spray stream, is difficult, making it difficult for particle sizes exceeding a critical value to penetrate the skin.

On the other hand, the smaller the particle size of the frozen particle, the less likely it is that the frozen particle will break upon impact, and it is easier to accelerate by the coolant, so it can be predicted that it will penetrate the stratum corneum more easily. However, it may be difficult to penetrate the stratum corneum from the following viewpoints.

First, in order to destroy and penetrate the stratum corneum of the skin, the collision energy against the stratum corneum must be greater than a critical value, and the collision energy is proportional to the mass of the frozen particle (i.e., proportional to the particle size) and the collision speed. Therefore, when the collision speed is constant, the smaller the particle size, the less the collision energy reaches the critical value, making penetration difficult.

Second, as the particle size of the frozen particles decreases, the surface area-to-volume ratio decreases, which increases the air resistance proportional to the surface area, lowering the collision speed. Consequently, the collision energy of the frozen particles does not reach the critical value for penetration, making penetration difficult. Specifically, as the particle size decreases, the surface area decreases less than the volume decreases, and thus the contact area with the air increases, resulting in increased air resistance. Therefore, when the accelerated speed is the same, the frozen particles with smaller particle sizes decelerate faster than the frozen particles with larger particles, preventing the collision energy from reaching the critical value required for penetration. Similarly, the resistance in the stratum corneum also increases as the particle size decreases, so the degree to which the frozen particles are decelerated by the stratum corneum increases. Consequently, the frozen particles with particle sizes below the critical value may have difficulty penetrating the stratum corneum.

As mentioned above, even if a composition is formed into solid frozen particles and applied to the skin, penetration is not always achieved. Frozen particles must have a specific particle size range to achieve penetration. Therefore, when performing a freeze spray method, it is crucial to identify a particle size that allows penetration. Furthermore, a device structure and control method for generating frozen particles of a size that allows penetration are required.

2. Penetrable particle size

The applicant first sought to determine the particle size of the frozen particles capable of penetrating the skin, and through experiments, determined the range of particle sizes capable of penetrating the skin. Below, the size range of frozen particles capable of penetrating the skin is described with reference to FIGS. 2 through 6.

FIG. 2 is a drawing showing frozen composition particles that are the target of particle size measurement according to one embodiment.

FIG. 3 is a drawing showing a method for measuring particle size according to one embodiment.

Figure 4 is a drawing showing the results of the first experiment to confirm the skin penetration effect of frozen composition particles and the particle size and velocity of the frozen composition particles in the first experiment.

Figure 5 is a drawing showing the results of a second experiment to confirm the skin penetration effect of frozen composition particles and the particle size and velocity of the frozen composition particles in the second experiment.

According to one embodiment of the present disclosure, skin penetration is possible when frozen particles having a particle size of 16 μm or more and 42 μm or less are collided with the skin surface.

Specifically, according to the results of the first experiment described below, it was confirmed that the composition reached the epidermis or dermis when the liquid composition was converted into solid frozen particles and sprayed on the skin, and the particle size was measured to be 16 μm or more and 42 μm or less. Accordingly, it can be interpreted that the frozen particles of the composition having a particle size of at least 16 μm or more and 42 μm or less are capable of penetration. The process and measurement method of the first experiment will be described below.

Meanwhile, as described above, the particle size of the frozen particles has a lower limit and an upper limit that can be penetrated, and in the case of frozen particles having a particle size between the lower limit and the upper limit, it can be understood as a particle size that can be penetrated.

Therefore, the range of particle sizes from 16㎛ to 42㎛ can be understood as being at least within the range between the lower and upper limits of the particle sizes that can be penetrated, and if the particle sizes are within the range from 16㎛ to 42㎛, the frozen particles having the corresponding particle sizes can be understood as frozen particles that can be penetrated. Here, the frozen particles that can be penetrated refer to frozen particles that can be penetrated when the accelerated speed and the collision speed are above a certain value, and do not refer to frozen particles that can be penetrated unconditionally regardless of the accelerated speed or the collision speed.

The range of particle sizes that can penetrate may vary depending on the impact speed at which the frozen particles collide with the skin surface or the magnitude of the force accelerating the frozen particles. According to the results of the first experiment described below, when the particle size of the frozen particles was measured to be 16 ㎛ or more and 42 ㎛ or less, the impact speed was measured to be 75 m/s to 110 m/s. Therefore, when the impact speed exceeds 110 m/s, the penetrable particle size may have a value of 16 ㎛ or less. Alternatively, when the impact speed is accelerated to exceed 75 m/s, the penetrable particle size may have a value of 42 ㎛ or more. However, regardless of the impact speed, the penetrable particle size may be included in a range below the critical lower limit and the critical upper limit.

According to another embodiment of the present disclosure, skin penetration is possible when frozen particles having a particle size of 10 μm or more and 80 μm or less are collided with the skin surface.

Specifically, according to the results of the second experiment described below, it was confirmed that the composition reached the epidermis or dermis when the liquid composition was converted into solid frozen particles and sprayed on the skin, and the particle size was measured to be 10 μm or more and 80 μm or less. Accordingly, it can be interpreted that the frozen particles of the composition having a particle size of at least 10 μm or more and 80 μm or less are capable of penetration. The process and measurement method of the second experiment will be described below.

Since the range of 10㎛ to 80㎛ above can be understood as being included in the range between the lower and upper limits of the particle size that can penetrate, if the particle size is included in the range of 10㎛ to 80㎛, the frozen particle having that particle size can be understood as a particle size that can penetrate. Here, the frozen particle that can penetrate means a frozen particle that can penetrate when the accelerated speed and the collision speed are above a certain value, and does not mean a frozen particle that can penetrate unconditionally regardless of the accelerated speed or the collision speed.

The range of particle sizes that can penetrate may vary depending on the impact speed at which the frozen particles collide with the skin surface or the magnitude of the force accelerating the frozen particles. According to the results of the second experiment described below, when the particle size of the frozen particles was measured to be 10 ㎛ or more and 80 ㎛ or less, the impact speed was measured to be 16 m/s to 48 m/s. Therefore, when the impact speed exceeds 48 m/s, the penetrable particle size may have a value of 10 ㎛ or less. Alternatively, when the impact speed is accelerated to exceed 16 m/s, the penetrable particle size may have a value of 80 ㎛ or more. However, regardless of the impact speed, the penetrable particle size may be included in a range below the critical lower limit and the critical upper limit.

The applicant conducted the first experiment as follows to determine the penetrable particle size.

The first experiment compared the penetration effects of applying a liquid composition to the skin surface (control group), spraying the liquid composition onto the skin surface in an unfrozen state (test group 1), and spraying the liquid composition onto the skin surface in a solid state after atomizing and freezing it (test group 2), and measured the size and speed of the frozen particles in test group 2.

The target onto which the composition was sprayed was human-derived skin tissue. Specifically, facial skin tissue discarded after surgery was used.

In the control group, human-derived skin tissue was cut into a certain size (2 cm x 2 cm) and the composition was applied. The composition contained Acetyl Hexapeptide-8 (Acetyl Hexapeptide-8-FITC) conjugated with a fluorescent substance (FITC, Fluorescein isothiocyanate) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image was taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis were confirmed.

In test group 1, human-derived skin tissue was cut to a certain size and sprayed with the composition without freezing. The composition contained antifreeze (PG) to prevent freezing by the coolant, and acetyl hexapeptide-8 conjugated with a fluorescent substance (FITC) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image was taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis were confirmed.

The freezing spray system described below was used as a method for spraying the composition. Specifically, the coolant spray device described below and the composition delivery device according to the second embodiment were used. No frozen particles were observed in Test Group 1.

In test group 2, human-derived skin tissue was cut into a certain size, frozen, and sprayed with the composition. The composition contained acetyl hexapeptide-8 conjugated with a fluorescent substance (FITC) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image was taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis were confirmed.

As a method for spraying the composition, a freeze spray system described below was used. Specifically, a coolant spray device described below and a composition providing device according to the second embodiment were used.

After the penetration experiment on human-derived skin tissue, the characteristics and freezing ratio of the frozen particles in test group 2 were measured.

As characteristics of the frozen particles, particle size and collision velocity were measured.

Particle size is the particle size of the frozen particles of the composition when they collide with the skin. The size of the frozen particles present in the observing region (OR) at a point in time during the time period in which the coolant and composition are sprayed through the freezing spray system can be measured as the particle size.

For example, referring to Fig. 2, a freeze injection system is photographed from the side using an ultra-high-speed camera, and an observation area (OR) is specified in the photographed video or image, which is spaced apart from the orifice of the nozzle of the coolant injection device by an observation distance (OD) and has an observation width (OW), and the particle size of the frozen particles to be measured included in the specified observation area (OR) can be measured. Referring to Fig. 3, since the frozen particles are displayed relatively dark compared to the liquid particles, by applying a threshold filter that selects pixels below a certain brightness for the specified observation area (OR), the frozen particles can be tracked, and the particle size can be measured by measuring the maximum width of the tracked frozen particles.

The observation distance (OD) can correspond to the distance from the nozzle to the target area when spraying the coolant and composition onto the target area using a freezing spray system. In Test Group 2, the observation distance (OD) was 10 mm.

The observation width (OW) can be determined within 1% to 50% of the observation distance (OD). In test group 2, the observation width (OW) was 1 mm to 2 mm.

The collision velocity of the frozen particles was calculated from the frame-by-frame positional changes of the frozen particles in the aforementioned observation area (OR). Specifically, the collision velocity was calculated by dividing the positional change values of the frozen particles to be measured in the first and second consecutive frames by the frame acquisition cycle.

The freezing ratio is the percentage of frozen particles among the total composition particles when the composition collides with the skin surface. The freezing ratio is a value representing the ratio of the solid state composition to the liquid state composition and the solid state composition in the observation area (OR) at a certain point in time during the time period in which the coolant and composition are sprayed through the freezing spray system.

The freezing rate in test group 1 was calculated as 0%, and the freezing rate in test group 2 was calculated as 17% (within 5% of the measurement error, approximately 12% to approximately 22%).

Meanwhile, in the first experiment described above and the second experiment described below, the characteristics of the frozen particles and the freezing ratio were measured using the above method, but the method for measuring the characteristics of the particles and the freezing ratio is not limited to the above method. For example, in addition to applying the filter described above, Dynamic light scattering (DLS) with polarization analysis, Time-resolved X-ray diffraction (TR-XRD), or in situ spectroscopy may be utilized as a method for confirming the frozen particles.

Figure 4 (a) is a graph showing the degree of penetration of the control group, test group 1, and test group 2. Referring to Figure 4 (a), in the first experiment, the fluorescence intensity was 192.04 in the control group, the fluorescence intensity was 637.65 in test group 1, whereas the fluorescence intensity was 2136.44 in test group 2. It can be seen that the degree of penetration of the composition was significantly improved in test group 2, where a portion of the composition was frozen and sprayed, compared to test group 1, where no frozen particles were observed. Considering that the freezing ratio was calculated as 17% in test group 2, it can be understood that the degree of penetration was significantly improved compared to test group 1, as most of the frozen particles in test group 2 penetrated.

Figure 4 (b) shows the particle size and impact velocity measured for 20 frozen particles in Test Group 2. Referring to Figure 4 (b), the minimum particle size of the frozen particles in Test Group 2 was 16 μm, the maximum was 42 μm, and the minimum impact velocity was 75 m/s, and the maximum was 110 m/s.

As mentioned above, considering that most of the frozen particles in test group 2 were penetrated, it can be seen that frozen particles with particle sizes of 16㎛ and 42㎛ can penetrate the skin. As mentioned above, particle sizes have a critical lower limit and a critical upper limit for penetration, and considering that penetration is difficult when the particle size is below the lower limit or exceeds the upper limit, it can be seen that a particle size of at least 16㎛ or more and 42㎛ or less is a particle size that can penetrate.

Therefore, in order to penetrate the stratum corneum in the freeze spray, the particle size of the freeze particles should be at least 16 ㎛ to 42 ㎛ and the impact should be performed. Preferably, the particle size should be at least 16 ㎛ to 42 ㎛ and the impact speed should be at least 75 m/s to 110 m/s and the impact should be performed.

The second experiment was conducted to compare the penetration effects of applying a liquid composition to the skin surface (control group), spraying the liquid composition onto the skin surface in an unfrozen state (test group 1), and spraying the liquid composition onto the skin surface in a solid state after being granulated and frozen (test group 3), and to measure the size and speed of the frozen particles in test group 3. Here, the control group and test group 1 were the same as in the first experiment, and the freezing ratio of test group 3 was set lower compared to test group 2 of the first experiment.

The target onto which the composition was sprayed was human-derived skin tissue. Specifically, facial skin tissue discarded after surgery was used.

For the control group and test group 1, the contents of the first experiment were applied as is, so a detailed description is omitted.

In test group 3, human-derived skin tissue was cut into a certain size, frozen, and sprayed with the composition. The composition contained acetyl hexapeptide-8 conjugated with a fluorescent substance (FITC) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image was taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis were confirmed.

As a method for spraying the composition, a freeze spray system described below was used. Specifically, a coolant spray device described below and a composition providing device according to the first embodiment were used.

After the penetration experiment on human-derived skin tissue, the characteristics and freezing ratio of the frozen particles in test group 3 were measured.

The particle size and collision velocity were measured as characteristics of the frozen particles, and the particle size, collision velocity, and freezing ratio were measured using the same method as in the first experiment, so the specific details are omitted.

In test group 3, the freezing rate was calculated to be 5% (within 1% of the measurement error, approximately 4% to approximately 6%).

Fig. 5(a) is a graph showing the degree of penetration of the control group, test group 1, and test group 3. Referring to Fig. 5(a), in the first experiment, the fluorescence intensity was 192.04 in the control group, the fluorescence intensity was 637.65 in test group 1, whereas the fluorescence intensity was 1399.54 in test group 3. As in the first experiment, it can be seen that the degree of penetration of the composition was significantly improved in test group 3, where a portion of the composition was frozen and sprayed, compared to test group 1, in which no frozen particles were observed. Although the degree of penetration was lower than that of test group 2 in the first experiment, considering that the freezing ratio in test group 3 was calculated to be 5%, the reason for the low degree of penetration in test group 3 is that the number of frozen particles was small, and considering that the fluorescence intensity in test group 3 was still more than twice that of test group 1 even though the freezing ratio was 5%, it can be understood that most of the frozen particles penetrated in test group 3 as well.

Figure 5 (b) shows the particle size and impact velocity measured for 20 frozen particles in test group 3. Referring to Figure 5 (b), the particle size of the frozen particles in test group 3 has a value of 10 ㎛ or more and 80 ㎛ or less, and the impact velocity has a value of 16 m/s or more and 48 m/s or less.

As described above, considering that most of the frozen particles in test group 3 were penetrated, it can be seen that frozen particles with particle sizes of 10 ㎛ and 80 ㎛ can penetrate the skin. As described above, particle sizes have a critical lower limit and a critical upper limit for penetration, and considering that penetration is difficult when the particle size is below the critical lower limit or above the critical upper limit, it can be seen that a particle size of at least 10 ㎛ or more and 80 ㎛ or less is a particle size that can penetrate.

However, considering that the average particle size of the frozen particles in test group 3 was 29.3 ㎛ and the second largest particle size was 48 ㎛, a particle size of 10 ㎛ to 48 ㎛ may be interpreted as a particle size that can penetrate.

Therefore, in order to penetrate the stratum corneum in the freezing spray, the particle size of the frozen particles may be at least 10 ㎛ to 80 ㎛ or 10 ㎛ to 48 ㎛ for collision. Preferably, the particle size may be at least 10 ㎛ to 80 ㎛ or 10 ㎛ to 48 ㎛ for collision, and the collision speed may be at least 16 m/s to 48 m/s for collision.

Meanwhile, the penetration depth of the composition can be determined depending on the particle size and collision velocity of the aforementioned frozen particles.

For example, in Test Group 2, when the particle size of the frozen particles is 16 ㎛ or more and 42 ㎛ or less, and the impact speed is 110 m/s or more, the penetration depth may become deeper. Alternatively, in Test Group 2, when the impact speed of the frozen particles is 75 m/s or more and 110 m/s or less, and the particle size of the frozen particles is 42 ㎛ or more, the penetration depth may become deeper.

As another example, in Test Group 3, when the size of the frozen particles is 10 ㎛ or more and 80 ㎛ or less and the impact speed is 48 m/s or more, the penetration depth may be deeper. Alternatively, in Test Group 3, when the impact speed of the frozen particles is 16 m/s or more and 48 m/s or less and the particle size of the frozen particles is 80 ㎛ or more, the penetration depth may be deeper.

In this way, the particle size and collision speed of the frozen particles can be controlled to allow the composition to penetrate into the skin to a desired depth. For example, the particle size of the frozen particles can be controlled to be 10 μm or more and 80 μm or less, and the collision speed can be controlled to be 16 m/s or more and 110 m/s or less, so that the penetration depth is 10 μm or more and 500 μm or less.

In the above, the particle sizes of the penetrable frozen particles confirmed through the first and second experiments are described. In the first experiment, the range of 16 ㎛ and 42 ㎛ was specified as the range of the penetrable particle size, and in the second experiment, the range of 10 ㎛ to 80 ㎛ was specified as the range of the penetrable particle size.

The penetrable particle size range is not limited to the two ranges described above and can be further specified through experimentation. Prophetic examples for specifying the penetrable particle size are described below.

The third experiment is conducted as follows.

The penetration effects of a liquid composition applied to the skin surface (control group), a liquid composition sprayed onto the skin surface in an unfrozen state (comparative test group), and a liquid composition granulated and frozen and sprayed onto the skin surface in a solid state (confirmation test group) are compared, and the size and speed of the frozen particles are measured in the confirmation test group.

The target onto which the composition is sprayed is human-derived skin tissue. Specifically, facial tissue discarded after surgery is used. Alternatively, a material similar to skin tissue (e.g., pig skin or rabbit skin) is used as the target onto which the composition is sprayed.

In the control group, human-derived skin tissue was cut into a certain size (2 cm x 2 cm) and the composition was applied. The composition contains Acetyl Hexapeptide-8 (Acetyl Hexapeptide-8-FITC) combined with a fluorescent substance (FITC, Fluorescein isothiocyanate) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image is taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis are confirmed.

In the comparative test group, human-derived skin tissue was cut to a certain size and sprayed with the composition without freezing. The composition contained antifreeze (PG) to prevent freezing by the coolant, and acetyl hexapeptide-8 conjugated with a fluorescent agent (FITC) to confirm penetration.

After 24 hours, a fluorescent transmission image is taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis are confirmed.

The method for spraying the composition uses the freeze spray system described below. Specifically, the coolant spray device described below and the composition providing device according to the second embodiment are used.

In the verification test group, human-derived skin tissue is cut to a certain size, frozen, and sprayed with the composition. The composition includes acetyl hexapeptide-8 conjugated with a fluorescent agent (FITC) to confirm the penetration effect.

After 24 hours, a fluorescent transmission image is taken of a cross-section of human-derived skin tissue, and the intensity and penetration depth of the fluorescent material located under the epidermis are confirmed.

The method for spraying the composition uses the freeze spray system described below. Specifically, the coolant spray device described below and the composition providing device according to the second embodiment are used.

Here, verification test groups are prepared by setting various combinations of particle size determining factors in the freeze spray system used. That is, verification test groups are prepared so that different freeze spray systems are implemented by selecting various values for the sharpness of the feed end, the distance between the feed end and the nozzle orifice, the coolant heating amount, the composition supply flow rate, and the coolant container pressure, and penetration tests are conducted for each verification test group.

After the penetration experiment on human-derived skin tissue, the particle size, impact velocity, and freezing ratio of the frozen particles were measured in each of the confirmation test groups. The measurement method was the same as that used in the first experiment above.

Among the confirmation test groups, those in which the penetration effect, i.e., the fluorescence intensity, is more than twice that of the comparison test group and the freezing ratio is less than 20% are selected, and each of the particle size ranges of the frozen particles measured in each of the selected confirmation test groups is determined as the permeable particle size range.

3. Particle size control of frozen particles

As described above, in the freeze spray method of impinging a composition on the skin in a frozen state, the particle size of the frozen composition must be within a permeable particle size range in order for the composition to penetrate the skin. Generally, the composition used in the composition spray is a pre-atomized liquid composition or a non-atomized liquid composition, and is provided contained in a composition container such as an ampoule or a vial, and exists in a liquid state at room temperature. Therefore, it is necessary to control the particle size of the non-atomized liquid composition so that it becomes a permeable particle size when it becomes frozen particles.

Meanwhile, as a method for controlling the particle size of frozen particles, there is a method of forming a liquid composition before particle formation into small particles having a desired particle size, freezing the composition to produce frozen particles having a desired particle size, and then spraying the frozen particles.

This method requires a number of devices, including a particle forming device, a device for providing formed particles, a device for freezing the particles, and a device for introducing the frozen particles into a carrier gas, in order to form and freeze the liquid composition into small particles before particle formation. In addition, a storage environment must be created in which the frozen particles can be stored without melting before being sprayed.

This method requires a large number of devices, expected to be quite bulky, and a control method to create a storage environment. This makes portable devices impossible, requires lengthy setup and use times, and requires significant costs and manpower to manage the devices. Consequently, systems or devices based on this method are difficult to implement in practice.

Hereinafter, with reference to FIGS. 6 to 16, a method for forming a liquid composition before particle formation into frozen particles having a desired particle size and causing them to collide with the skin and a freeze spray system (100) for performing the same will be described.

Figure 6 is a schematic diagram illustrating a freeze spray system (100) according to one embodiment. The freeze spray system (100) sprays a coolant and a composition together, causing the liquid composition to become solid frozen particles and collide with the skin. The freeze spray system (100) mixes the composition into the coolant spray stream and sprays it, and may therefore be referred to as a mixed spray system.

The freeze spray system (100) adopts a method of spraying a composition using a coolant. Referring to FIG. 6, the freeze spray system (100) may include a coolant spray device (1000) and a composition providing device (2000).

The coolant injection device (1000) refers to a device that injects a coolant. The coolant injection device (1000) includes at least a refrigerant container (RC) in which a coolant is stored, a flow regulator (1200) that controls the movement of the coolant so that the coolant is injected or not injected from the coolant injection device (1000), and a nozzle (1500) through which the coolant is injected. In addition to the aforementioned components, the coolant injection device (1000) may further include other components necessary for operation. Additional components of the coolant injection device (1000) will be described later.

The composition providing device (2000) refers to a device that provides a composition. The composition providing device (2000) may include a composition container (CC) in which the composition is stored and a composition guide (2100) for discharging the composition. The composition guide (2100) may include an input terminal through which the composition stored in the composition container (CC) is introduced and an output terminal through which the composition is discharged. In addition to the aforementioned components, the composition providing device (2000) may further include other components necessary for operation. Additional components of the composition providing device (2000) will be described later.

The composition providing device (2000) is connected to the coolant injection device (1000) and can provide the composition to the coolant injected from the coolant injection device (1000). Specifically, a coolant injection stream is formed by the nozzle (1500) of the coolant injection device (1000), and the composition guide (2100) of the composition providing device (2000) can be positioned adjacent to the nozzle (1500).

Here, the coolant injection stream refers to a coolant flow including coolant particles injected from the nozzle (1500). The coolant injection stream formed by the nozzle (1500) forms a negative pressure at the output end of the composition guide (2100), and the composition can move along the composition guide (2100) due to the negative pressure and be introduced into the coolant injection stream. Alternatively, the composition providing device (2000) includes an actuator (2200) fluidly connected to the composition container (CC), and the composition can be supplied to the composition guide (2100) at a constant flow rate or a constant range of flow rates by the actuator (2200) and introduced into the coolant injection stream.

The composition introduced into the coolant spray stream may collide with coolant particles within the coolant spray stream and be sprayed together. Within the coolant spray stream, the composition may be broken into small, fine particles by the high velocity of the coolant spray stream and cooled by heat exchange with the coolant spray stream having a relatively low temperature. In this way, the composition and coolant may be mixed and sprayed in the freeze spray system (100).

Meanwhile, the internal pressure of the coolant container (RC) in which the coolant is stored may be about 10 bar to 1000 bar at room temperature. Alternatively, the internal pressure of the coolant container (RC) may be about 30 bar to 200 bar at room temperature. Alternatively, the internal pressure of the coolant container (RC) may be about 50 bar at room temperature. The internal pressure of the coolant container (RC) may be related to the rate at which the coolant expands when flowing out from the nozzle (1500) of the coolant injection device (1000). In other words, the higher the internal pressure of the coolant container (RC), the higher the speed of the coolant particles in the coolant injection stream. Considering that the pressure of the compressed air used in the aforementioned airbrush method is about 1 bar to 5 bar, using a high-pressure coolant as a delivery medium can significantly increase the spray speed of the composition, thereby improving the penetration effect of the composition.

FIG. 7 is a diagram showing a process of atomizing and freezing a pre-atomized liquid composition according to one embodiment.

Referring to (a) of FIG. 7, the composition guide (2100) is positioned adjacent to the nozzle (1500), and when a refrigerant spray stream is formed by the nozzle (1500), a negative pressure is formed around the supply end (2110) of the composition guide (2100) according to Bernoulli's principle. Here, the supply end (2110) means a portion including one end of the composition guide (2100) facing the nozzle (1500).

The liquid composition before particle formation in the composition guide (2100) moves to the supply end (2110) by the formed negative pressure and is deposited at the supply end (2110). The composition deposited at the supply end (2110) is separated from the supply end (2110) by the coolant sprayed from the nozzle (1500) and enters the coolant spray stream.

At this time, the liquid composition before particle formation formed at the supply end (2110) is partially separated by the coolant, thereby generating droplets of the composition.

Meanwhile, the coolant injection stream generated by the nozzle (1500) can be divided into a main stream (S1) and a sub stream (S2).

The main stream (S1) has a higher coolant density than the sub stream (S2). In addition, the coolant injection speed is faster in the main stream (S1) than in the sub stream (S2) in a direction parallel to the central axis of the nozzle (1500), and the coolant in the main stream (S1) moves in a straight line to the target area. The coolant in the main stream (S1) can have a speed faster than the speed of sound. In the main stream (S1), external substances such as air have little effect on the flow of the coolant.

As the coolant moves rapidly within the main stream (S1), the surrounding air surrounding the main stream (S1) is sucked into the main stream (S1) where the pressure is relatively low. At this time, a region where a velocity gradient and a temperature gradient begin to develop is created, and this region is called the sub stream (S2).

The sub-stream (S2) contains the ambient air drawn in by the main stream (S1) and a portion of the injected coolant. The sub-stream (S2) has a higher temperature than the main stream (S1) and a cooler temperature than the ambient air. The temperature of the sub-stream (S2) increases as it moves away from the central axis of the nozzle (1500).

In the sub-stream (S2), the injection speed of the coolant decreases as the inflowing ambient air collides with the injected coolant. That is, the speed of the coolant in the sub-stream (S2) is lower than that of the coolant in the main stream (S1). In the sub-stream (S2), the speed of the coolant decreases as it moves away from the central axis of the nozzle (1500).

In freeze spraying, to increase the freezing rate, the composition needs to be introduced into the main stream (S1) having a relatively low temperature. However, if the supply end (2110) of the composition guide (2100) is positioned within the main stream (S1) for this purpose, the composition may freeze before being separated from the supply end (2110). Therefore, the supply end (2110) needs to be positioned in an area of the coolant spray stream that is close to the main stream (S1) but has a temperature that does not freeze.

The supply end (2110) of the composition guide (2100) may be positioned at the boundary between the main stream (S1) and the sub stream (S2). Composition droplets falling from the supply end (2110) may move to the main stream (S1). Meanwhile, the supply end (2110) of the composition guide (2100) does not always have to be positioned at the boundary between the main stream (S1) and the sub stream (S2). As described below, the position of the supply end (2110) may be determined in consideration of the desired particle size of the frozen particles.

Referring to Fig. 7(b), the composition droplets introduced into the coolant injection stream can be atomized upon collision with the coolant. Specifically, the composition droplets can be broken into smaller particles by being subjected to forces such as shear force or pressure exerted by the coolant particles moving at high speed within the coolant injection stream.

Referring to Fig. 7(b), the liquid atomized particles of the composition can be frozen within the coolant spray stream. As described below, the coolant sprayed by the nozzle (1500) is rapidly cooled instantaneously to a relatively low temperature (e.g., -50°C), and thus the coolant spray stream also has a low temperature. The liquid atomized particles move within the coolant spray stream and exchange heat with the coolant, thereby lowering their temperature. When the temperature drops below the freezing point of the composition, the liquid atomized particles freeze, becoming solid frozen particles.

Meanwhile, in that the composition is broken into small particles by the coolant jet stream generated by the nozzle (1500), the nozzle (1500) may be referred to as a cryogen jet based atomization module or an atomization inducing module.

In addition, as described below, the size of the composition droplets introduced into the coolant injection stream varies depending on the shape of the supply end (2110), and accordingly, the size of the frozen particles varies, so the supply end (2110) may be referred to as an atomization size determination module.

FIG. 8 is a drawing showing a freeze spray system (100) according to one embodiment. Referring to FIG. 8, the freeze spray system (100) includes a coolant spray device (1000) and a composition providing device (2000), and the composition providing device (2000) can be coupled to a nozzle (1500) of the coolant spray device (1000).

Meanwhile, as illustrated in FIG. 8, the freeze spray system (100) may further include a cover (COV) that supports the composition providing device (2000) while covering the nozzle (1500).

Hereinafter, for convenience of explanation, the case where the composition providing device (2000) is coupled to the nozzle (1500) of the coolant injection device (1000) is described, but the technical idea of the present disclosure is not limited thereto. The composition providing device (2000) may be coupled to a cover (COV) or a housing of the coolant injection device (1000) in addition to the nozzle (1500). However, even in this case, the composition guide (2100) of the composition providing device (2000) must be arranged adjacent to the nozzle (1500) of the coolant injection device (1000) so that the composition discharged from the composition guide (2100) can flow into the coolant injection stream formed from the nozzle (1500).

FIG. 9 is a drawing showing the configurations of a coolant injection device (1000) according to one embodiment. Referring to FIG. 9, the coolant injection device (1000) may include a container receiving portion (1100), a flow control portion (1200), a heat providing portion (1300), a nozzle coupling portion (1400), a nozzle (1500), a sensor portion (1600), an input portion (1700), an output portion (1800), and a control portion (1900).

The container receiving portion (1100) can receive a coolant container (RC). The container receiving portion (1100) is provided with a coolant receiving portion into which coolant can be introduced, and the coolant receiving portion can be understood as having a configuration including a flow path or hole for the coolant to move.

For example, the coolant container (RC) may be provided as a portable cartridge, and the coolant container (RC) may be mounted or removed from the container receiving portion (1100). When the coolant container (RC) is mounted on the container receiving portion (1100), the coolant inside the coolant container (RC) may move to the coolant receiving portion of the container receiving portion (1100).

When the coolant container (RC) is provided as a cartridge and mounted in the container receiving portion (1100), a configuration for perforating a cartridge inlet to allow coolant to exit the cartridge and a configuration for sealing the cartridge inlet to prevent coolant from leaking to the outside may be required. Accordingly, a configuration for perforation and a configuration for sealing may be arranged between the container receiving portion (1100) and the coolant container (RC).

As another example, the coolant container (RC) may be provided as a tank that is difficult to carry, and the container receiving portion (1100) may be connected to the coolant container (RC) via a tube. The coolant inside the coolant container (RC) may be moved to the coolant receiving portion of the container receiving portion (1100) via the tube.

The flow control unit (1200) can control the movement of the coolant. For example, the flow control unit (1200) includes a valve, and the coolant may or may not move depending on whether the valve is opened or closed. Furthermore, the degree to which the coolant moves can be determined depending on the degree to which the valve is opened or closed.

Here, the valve may be, for example, a solenoid valve, but the technical idea of the present disclosure is not limited thereto.

The container receiving portion (1100) and the flow control portion (1200) are fluidly connected so that the coolant flowing into the coolant receiving portion of the container receiving portion (1100) can move to the flow control portion (1200). For example, the coolant receiving portion of the container receiving portion (1100) and the flow path of the flow control portion (1200) can be directly connected. In another example, the coolant receiving portion of the container receiving portion (1100) and the flow control portion (1200) can be connected by a conduit.

As described below, the coolant injection device (1000) may be equipped with a precision temperature control function that precisely controls the temperature of the injection area where the coolant is injected. The heat supply unit (1300) is one of the means for implementing the precision temperature control function and can provide heat to the coolant before the coolant is injected.

In order to achieve the purpose of precisely controlling the temperature of the injection area, the coolant injection device (1000) can heat the high-pressure/low-temperature coolant using the heat providing unit (1300) before injecting the coolant.

The heat supply unit (1300) may include a heat source and a heat transfer medium. The heat source is a component that produces heat, and may include, for example, a thermoelectric element that utilizes a thermoelectric effect such as the Peltier effect. In this case, the amount of heat energy produced by the heat source may vary depending on the amount of power or current supplied to the heat source. The heat transfer medium may provide heat produced by the heat source to a coolant. For example, the heat transfer medium may receive heat energy from the heat source and transfer the received heat energy to a coolant.

The heat transfer medium can be configured in various forms, for example, the heat transfer medium can have a configuration in which a heat source is thermally coupled to the heat transfer medium, at least one flow path is formed within the heat transfer medium for a coolant to move, and thereby the contact area between the heat transfer medium and the coolant (i.e., heat transfer area) can be maximized.

The flow control unit (1200) and the heat providing unit (1300) are fluidly connected so that the coolant can move from the flow control unit (1200) to the heat providing unit (1300). For example, the flow path of the flow control unit (1200) and the flow path of the heat providing unit (1300) can be directly connected. In another example, the flow control unit (1200) and the heat providing unit (1300) can be connected by a conduit.

A coolant can be sprayed through the nozzle (1500). The nozzle (1500) has a flow path formed therein for the coolant to move. The flow path formed in the nozzle (1500) is narrower at the other end where the coolant is sprayed than at the one end where the coolant flows in. Before the coolant is sprayed from the other end of the nozzle (1500), the coolant is maintained at high pressure, and the coolant sprayed from the other end of the nozzle (1500) expands adiabatically and is sprayed at high speed, thereby being rapidly cooled. At this time, the higher the pressure of the coolant flowing into the nozzle (1500), the lower the temperature and higher the speed of the adiabatically expanded coolant. For example, when the internal pressure of the coolant container (RC) is 50 bar, the pressure of the coolant flowing into the nozzle (1500) is also close to 50 bar, and the coolant sprayed from the nozzle (1500) may have a temperature of approximately -50°C. If a cryogenic coolant with the high pressure required for high-speed injection is directly sprayed onto the skin, it can cause cell necrosis. To prevent skin damage such as cell necrosis, thermal energy can be applied before the coolant is sprayed using the heat supply unit (1300) described above.

The nozzle (1500) is detachable from the coolant injection device (1000). A nozzle coupling part (1400) may be provided to allow the nozzle (1500) to be detachably attached to the coolant injection device (1000).

The nozzle (1500) may be equipped with a composition providing device (2000). For example, a portion of the composition providing device (2000) may be coupled to the nozzle (1500) so that the output end of the composition guide (2100) of the composition providing device (2000) is positioned adjacent to the orifice of the nozzle (1500).

Meanwhile, the flow control unit (1200), the heat providing unit (1300), and the nozzle (1500) are fluidly connected to each other, but the arrangement methods may vary. For example, the heat providing unit (1300) may be arranged between the flow control unit (1200) and the nozzle (1500), so that the coolant may pass through the flow control unit (1200) to reach the heat providing unit (1300), and then pass through the heat providing unit (1300) to reach the nozzle (1500). In another example, the flow control unit (1200) may be arranged between the heat providing unit (1300) and the nozzle (1500), so that the coolant may pass through the heat providing unit (1300) to reach the flow control unit (1200), and then pass through the flow control unit (1200) to reach the nozzle (1500).

The sensor unit (1600) can measure the temperature of the spray area where the coolant is sprayed. For example, the sensor unit (1600) can measure the temperature of the skin surface where the coolant is sprayed and provide the measurement information to the control unit (1900).

Meanwhile, the sensor unit (1600) may also measure the temperature of some components of the composition providing device (2000). For example, the sensor unit (1600) may measure the temperature of the composition guide (2100) or the mixing unit (2300) and provide the measurement information to the control unit (1900).

The input unit (1700) can receive a user's input. For example, the input unit (1700) includes at least one push button switch and can provide a push input signal to the control unit (1900) according to the user's pressing of the switch, and the control unit (1900) can control the opening and closing of the flow control unit (1200) based on the push input signal. In addition, the input unit (1700) includes at least one rotary switch and can provide a rotary input signal to the control unit (1900) according to the user's operation, and the control unit (1900) can set a target temperature or a target time, etc. based on the rotary input signal. Here, the target temperature refers to a temperature to be reached by controlling the temperature of the spray area. In addition, the target time may refer to a time during which the spray of the coolant should be maintained or a time during which the temperature of the spray area should be maintained at the target temperature. In addition, the user can use the input unit (1700) to set a target penetration depth of the composition. The freezing spray system (100) can control the size of freezing particles and thereby adjust the penetration depth by controlling the heat applied to the coolant or the flow rate of the composition as described below.

The output unit (1800) can output an interface and various information for the use of the coolant injection device (1000) to the user. For example, the output unit (1800) includes a display and can output an interface for setting the target temperature or target time, etc., described above through the display. During operation of the coolant injection device (1000), information such as the real-time temperature of the injection area measured by the sensor unit (1600) or the total time for which the coolant has been injected can be output.

The control unit (1900) can control the configurations of the coolant injection device (1000). For example, the control unit (1900) can control the temperature of the coolant to be injected by controlling the heat supply unit (1300), can control the flow of the coolant by controlling the flow control unit (1200), and can output specific information to the user through the output unit (1800).

The coolant injection device (1000) can operate as follows.

First, the control unit (1900) can set a target temperature and target time. For example, the control unit (1900) can provide an interface that prompts the user to set the target temperature and target time through the output unit (1800), receive a setting input signal according to the user's operation through the input unit (1700), and set the target temperature and target time based on the received setting input signal.

Thereafter, the control unit (1900) outputs a message indicating to the user that operation preparation is complete through the output unit (1800), receives a switch-on input signal according to the user's operation through the input unit (1700), and can spray a coolant based on the received switch-on input signal.

While the coolant is being sprayed, the control unit (1900) can perform precise cooling of the spray area. For example, while the coolant is being sprayed, the control unit (1900) can obtain the real-time temperature of the spray area measured by the sensor unit (1600), compare the obtained real-time temperature with a set target temperature, and control the heat providing unit (1300). Specifically, if the obtained temperature value is lower than the target temperature, the control unit (1900) can increase the heat energy applied to the coolant through the heat providing unit (1300), and if the obtained temperature value is higher than the target temperature, the control unit (1900) can decrease the heat energy applied to the coolant through the heat providing unit (1300). At this time, the control unit (1900) can use PID control (Proportional Integral Derivative control) as a feedback control technique.

As precision cooling is performed by the control unit (1900), the temperature of the injection area can be controlled within a certain error range based on the target temperature.

Meanwhile, the control unit (1900) can provide heat to the coolant using the heat supply unit (1300) regardless of the temperature of the injection area. For example, the control unit (1900) can control the heat supply unit (1300) to provide thermal energy per unit time. In this case, temperature measurement for the injection area may not be performed.

Although not illustrated in FIG. 9, the coolant injection device (1000) may further include a distance maintenance unit. When spraying coolant into a spray area, it is preferable that the distance between the target area and the coolant injection device (1000) be maintained constant. For example, it is preferable that the coolant and composition be sprayed while the nozzle (1500) of the coolant injection device (1000) is positioned within a recommended spray distance range with respect to the target area.

In particular, when it is necessary to measure and monitor the temperature of the injection area in the coolant injection device (1000) (e.g., performing feedback control using the temperature of the target area, stopping the operation of the device when the temperature of the target area falls below a safe temperature, or outputting the real-time temperature of the target area to the user, etc.), the temperature of the injection area needs to be accurately measured.

The distance maintainer may be positioned adjacent to the nozzle (1500). The distance maintainer may be connected to the housing of the coolant injection device (1000). The length of the distance maintainer may be designed such that the distance from the orifice of the nozzle (1500) to the end of the distance maintainer in a direction parallel to the central axis (CA) of the nozzle (1500) is within a recommended injection distance range. For example, the length of the distance maintainer may be determined based on the injection distance for maintaining the freezing ratio of the composition above a certain value.

Meanwhile, the coolant injection device (1000) is not limited to the above-described embodiment, and any device or structure that performs the function of injecting coolant by being directly or indirectly connected to a coolant container (RC) through a tube can be regarded as the coolant injection device (1000) described in the present disclosure. For example, the coolant injection device (1000) may not heat the coolant, and thus the heat providing unit (1300) and the sensor unit (1600) may be omitted.

Fig. 10 is a drawing showing a composition providing device (2000) according to the first embodiment. Fig. 10 (a) shows a state in which the composition providing device (2000) is coupled to a nozzle (1500), and Fig. 10 (b) shows a state in which the composition and coolant are mixed and sprayed in a cross-section (A-A') in a state in which the composition providing device (2000) is coupled to the nozzle (1500).

Referring to FIG. 10, the composition providing device (2000) may include a composition guide (2100), a mixing unit (2300), a composition container (CC), and a combining unit (2400).

The composition guide (2100) serves to guide the movement of the composition. For example, as illustrated in (b) of FIG. 10, the composition guide (2100) fluidly connects the composition container (CC) and the mixing unit (2300), and the composition stored in the composition container (CC) can move to the mixing unit (2300) through the composition guide (2100). The composition guide (2100) may be implemented in the form of a tube. The composition guide (2100) may include an input terminal through which the composition is introduced and an output terminal through which the composition is discharged.

The mixing unit (2300) provides a mixing space (MS) where the composition and the coolant are mixed. As illustrated in (b) of FIG. 10, the mixing unit (2300) has an inner surface defining the mixing space (MS). An output terminal of the composition guide (2100) may be positioned on the inner surface of the mixing unit (2300). The mixing space (MS) is fluidly connected to the nozzle (1500) of the coolant injection device (1000), so that when the coolant is injected from the nozzle (1500), a coolant injection stream may be formed in the mixing space (MS).

The coolant injection stream can be divided into a main stream (S1) and a sub stream (S2). The main stream (S1) may refer to an area where the coolant is injected relatively strongly, and the sub stream (S2) may refer to an area where the coolant is injected relatively weakly. Alternatively, the main stream (S1) may refer to an area where the coolant density is relatively high, and the sub stream (S2) may refer to an area where the coolant density is relatively low.

The main stream (S1) and the sub stream (S2) can be distinguished based on the central axis (CA) of the nozzle (1500). For example, when the coolant injection stream is cut perpendicularly to the central axis (CA) of the nozzle (1500), the main stream (S1) can be located within a boundary distance from the central axis (CA) of the nozzle (1500), and the sub stream (S2) can be located outside the boundary distance from the central axis (CA) of the nozzle (1500). The boundary distance can be changed depending on the distance from the end of the nozzle (1500), and can vary depending on the internal pressure of the coolant container (RC) and the size of the orifice of the nozzle (1500). As another example, in the coolant injection stream, an area where the temperature of the coolant is below a critical temperature can be distinguished as the main stream (S1), and the remaining area can be distinguished as the sub stream (S2). For another example, in a coolant injection stream, a region where the average speed of the coolant is greater than or equal to a critical speed may be designated as a main stream (S1), and the remaining region may be designated as a sub stream (S2). For another example, in a coolant injection stream, a region where the density of the coolant is greater than or equal to a critical density may be designated as a main stream (S1), and the remaining region may be designated as a sub stream (S2).

Meanwhile, it is important that the composition is introduced into the main stream (S1) among the coolant injection streams. Since the coolant velocity is higher and the temperature is lower in the main stream (S1) than in the sub stream (S2), the temperature of the composition is lower and the injection velocity of the composition is higher when the composition meets coolant particles in the main stream (S1) and is injected than when the composition meets coolant particles in the sub stream (S2) and is injected.

The composition container (CC) can store the composition. The composition container (CC) can be provided with an inlet for injecting the composition. The composition container (CC) can be provided with a vent for allowing external air to enter.

The coupling part (2400) refers to a part that is coupled to the nozzle (1500) in the composition providing device (2000). For example, the coupling part (2400) includes a hook coupling member, a screw coupling member, or a force-fit coupling member, and can be coupled and fixed to one area of the nozzle (1500).

When a coolant injection stream is formed in the mixing space (MS), the coolant is injected adjacent to the output end of the composition guide (2100), and a negative pressure is formed at the output end of the composition guide (2100) according to Bernoulli's principle. The composition container (CC) has a vent hole formed therein, so that the internal pressure is maintained at atmospheric pressure. Accordingly, the composition stored in the composition container (CC) moves to the output end of the composition guide (2100) where a lower pressure is formed, and as a result, is introduced into the coolant injection stream.

Meanwhile, a guide plate may be installed in the mixing unit (2300) to move the composition to the main stream (S1) of the coolant injection stream. The guide plate includes a surface having a preset length. One end of the guide plate may be positioned adjacent to the output end of the composition guide (2100), and the other end of the guide plate may be positioned adjacent to the main stream (S1). Accordingly, the composition introduced through the composition guide (2100) may move along the guide plate and reach the main stream (S1).

The components of the composition providing device (2000) may be manufactured integrally. Alternatively, at least some of the components of the composition providing device (2000) may be manufactured separately and connected to each other.

Fig. 11 is a drawing showing a composition providing device (2000) according to a second embodiment. Fig. 11 (a) shows a state in which the composition providing device (2000) is coupled to a nozzle (1500), and Fig. 11 (b) shows a state in which the composition and coolant are mixed and sprayed in a cross-section (B-B') in a state in which the composition providing device (2000) is coupled to the nozzle (1500).

Referring to FIG. 11, the composition providing device (2000) may include a composition guide (2100), a composition container (CC), an actuator (2200), and a coupling part (2400).

The composition guide (2100) is configured to receive the composition from the composition container (CC) and supply it to the coolant injection stream. The composition guide (2100) includes an input terminal through which the composition is introduced and an output terminal through which the composition is discharged.

Referring to (b) of FIG. 11, a composition path through which the composition can move is formed inside the composition guide (2100), and the output end of the composition guide (2100) may be arranged adjacent to the orifice of the nozzle (1500). Specifically, the output end of the composition guide (2100) may be arranged at a first distance in a direction parallel to the central axis (CA) of the nozzle (1500) and a second distance in a direction perpendicular to the central axis (CA) of the nozzle (1500) based on the orifice of the nozzle (1500). At this time, the output end of the composition guide (2100) may be positioned to contact the main stream (S1) of the coolant injection stream formed by the nozzle (1500). For example, the first distance and the second distance may be determined according to the boundary of the main stream (S1) and the sub stream (S2) of the coolant injection stream. The positional relationship between the output terminal of the composition guide (2100) and the nozzle (1500) will be described later.

The composition container (CC) is a structure in which the composition is stored. The composition container (CC) may be provided with an inlet for injecting the composition. The composition container (CC) may be fluidly connected to an actuator (2200). The composition inside the composition container (CC) may be pressurized by the actuator (2200) and moved to the composition guide (2100).

The actuator (2200) may be configured to supply fluid to the mixing unit (2300) at a preset flow rate. The actuator (2200) may include, for example, a piston and an electric motor, and may pressurize the fluid by moving the piston when powered.

The joint (2400) is omitted as it is the same as described above.

Referring to (b) of FIG. 11, when a coolant injection stream is formed by the coolant injection device (1000), the actuator (2200) of the composition providing device (2000) operates to pressurize the composition in the composition container (CC), thereby allowing the composition to flow into the coolant injection stream through the composition guide (2100). At this time, the flow control unit (1200) and the actuator (2200) may be controlled by the control unit (1900). For example, the flow control unit (1200) may be operated first to inject the coolant, and then the actuator (2200) may be operated to discharge the composition. In another example, the flow control unit (1200) and the actuator (2200) may be operated simultaneously.

Although the coolant injection device (1000) and the composition providing device (2000) are described above as being manufactured separately and then coupled to each other, the technical idea of the present disclosure is not limited thereto. For example, some of the components of the composition providing device (2000) may be mounted on the coolant injection device (1000), and some of the components of the coolant injection device (1000) may be implemented on the composition providing device (2000). Specifically, the composition providing device (2000) may include a component that performs the function of the nozzle (1500), and the composition providing device (2000) may be coupled to the nozzle coupling portion (1400) of the coolant injection device (1000).

As described above, a coolant injection stream is formed by the coolant injection device (1000), and a composition can be introduced into the coolant injection stream by the composition providing device (2000). The composition introduced into the coolant injection stream can be broken into fine particles in the coolant injection stream, and can be frozen into fine particles through heat exchange with a coolant having a temperature relatively low compared to the temperature of the composition. At this time, the size of the fine particles can be about 10 um to about 300 um. Alternatively, the size of the fine particles can be about 10 um to about 100 um.

However, as described below, the particle size of the frozen particles of the composition may be determined depending on the design method and control method of the freezing injection system (100). Specifically, the particle size of the frozen particles may be determined by the distance between the nozzle (1500) and the supply end (2110), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the composition supply flow rate, the amount of coolant heating, and the pressure of the coolant container (RC).

Below, a freeze spraying method using a freeze spraying system (100) is described with reference to FIG. 12.

Fig. 12 is a flowchart showing a freeze spraying method according to one embodiment.

Referring to FIG. 12, the freeze spray method includes a step of preparing a freeze spray system (100) (S1100), a step of positioning the freeze spray system (100) based on a target area (S1200), and a step of spraying a composition and a coolant together on the target area using the freeze spray system (100) (S1300).

Each step is described in detail below.

First, a user (or practitioner) may prepare a freezing spray system (100) (S1100). The freezing spray system (100) includes at least a nozzle (1500) for forming a coolant spray stream and a composition guide (2100) positioned adjacent to the nozzle (1500). In addition to the nozzle (1500) and the composition guide (2100), the freezing spray system (100) may include other components described above.

The user can position the freezing spray system (100) based on the target area (S1300).

For example, a user may position a nozzle (1500) of a freeze spray system (100) at a certain distance from a target area.

Here, the predetermined distance may be substantially the same as the recommended spray distance described above. If the recommended spray distance is presented as a range, the predetermined distance may be included within the recommended spray distance range.

Also, here, the central axis (CA) of the nozzle (1500) may have a preset angle with respect to the target area. For example, the angle formed by the central axis (CA) of the nozzle (1500) and a plane containing the target area or a virtual plane tangent to the target area may have a value between about 45° and 90°.

A user can spray a composition and a coolant together on a target area using a freeze spray system (100) (S1300). For example, when a user operates an input unit (1700) provided on the freeze spray system (100), the flow control unit (1200) opens and an actuator (2200) pressurizes the composition, so that the coolant and the composition can be sprayed together on the target area. If the freeze spray system (100) does not include an actuator (2200), when a user operates the input unit (1700) (e.g., presses a spray start button), the flow control unit (1200) opens, so that a coolant spray stream is formed, and the composition can be introduced into the coolant spray stream by negative pressure and sprayed.

Below, with reference to FIGS. 13 and 14, factors related to the device structure and design among the factors determining the particle size of frozen particles are described.

FIG. 13 is a drawing showing the distance between a nozzle (1500) and a supply end (2110) according to one embodiment. (a) of FIG. 13 shows the horizontal distance (HD) between the nozzle (1500) and the supply end (2110), and (b) of FIG. 13 shows the vertical distance (VD) between the nozzle (1500) and the supply end (2110).

Referring to FIG. 13, the horizontal distance and vertical distance between the supply end (2110) of the composition guide (2100) and the nozzle (1500) can be determined according to the positional relationship between the composition guide (2100) and the nozzle (1500).

Referring to (a) of Fig. 13, the horizontal distance (HD) means the distance that the supply end (2110) is away from the orifice of the nozzle (1500) in a direction parallel to the central axis (CA) of the nozzle (1500).

As the horizontal distance (HD) decreases, the particle size of the frozen particles may decrease. Specifically, as the horizontal distance (HD) decreases, that is, as the supply end (2110) gets closer to the orifice of the nozzle (1500) in the horizontal direction (or in the direction parallel to the central axis), the position at which the composition enters the coolant spray stream also gets closer to the orifice, which means that the composition is introduced closer to the beginning (or inlet) of the coolant spray stream. As the composition gets closer to the beginning of the coolant spray stream, the time the composition stays in the coolant spray stream increases, and the time it is subjected to shear force or pressure, etc. by the coolant particles within the coolant spray stream increases. As the time for which the composition is subjected to shear force or pressure, etc. by the coolant particles within the coolant spray stream increases, the number of times the composition is split increases, and accordingly, the size of the liquid atomized particles decreases, and consequently, the size of the frozen particles also decreases. However, if the specific heat of the composition is low or the freezing point is high enough that the freezing process occurs before the composition is sufficiently broken down, the particle size of the frozen particles may not decrease even if the horizontal distance (HD) is shortened.

Additionally, since the velocity of the coolant particles is high at the beginning of the coolant injection stream, the magnitude of the shear force or pressure applied to the composition increases, which can rapidly fragment the composition. Rapid fragmentation of the composition increases the number of fragments, which can ultimately lead to a smaller size of the frozen particles.

Conversely, a larger horizontal distance (HD) may result in a larger particle size of the frozen particles. As described above, a larger horizontal distance (HD) reduces the time that the composition is subjected to shear or pressure from the coolant particles within the coolant spray stream, thereby reducing the number of times the composition is broken up, resulting in a larger liquid atomization particle size and, consequently, a larger frozen particle size.

Additionally, the velocity of the coolant particles decreases as they move away from the start of the coolant injection stream, reducing the amount of shear or pressure applied to the composition, which may result in slower fragmentation of the composition. Slower fragmentation of the composition reduces the number of fragmentations, which may result in larger frozen particle sizes.

Referring to (b) of Fig. 13, the vertical distance (VD) means the distance at which the supply end (2110) is separated from the central axis (CA) of the nozzle (1500).

The smaller the vertical distance (VD), the closer the composition is introduced to the center of the coolant injection stream. The closer the composition is to the center of the coolant injection stream, the higher the speed of the coolant particles, so the magnitude of the shear force or pressure applied to the composition increases, which can rapidly fragment the composition. As the composition fragments rapidly, the number of fragments increases, and as a result, the size of the frozen particles can be reduced. However, if the specific heat of the composition is low or the freezing point is high enough that the freezing process occurs before the composition is sufficiently fragmented, the particle size of the frozen particles may not be reduced even if the vertical distance (VD) is shortened.

Conversely, as the vertical distance (VD) increases, the composition inlet distance increases from the center of the coolant spray stream. The velocity of the coolant particles decreases with distance from the center of the coolant spray stream, thereby reducing the shear force or pressure applied to the composition, thereby slowing the composition's fragmentation. This slow fragmentation reduces the number of fragments, which in turn increases the size of the frozen particles.

As described above, the particle size of the frozen particles of the composition can be determined by the distance between the supply end (2110) and the orifice of the nozzle (1500). Accordingly, the horizontal distance (HD) and the vertical distance (VD) between the supply end (2110) and the orifice of the nozzle (1500) in the frozen spray system (100) are experimentally calculated so that the frozen particles have the above-described penetrable particle size, and the positional relationship of the composition guide (2100) and the nozzle (1500) is designed in consideration of the calculated values, and the frozen spray system (100) can be manufactured according to the designed positional relationship.

For example, when the particle size determining factors such as the shape of the composition guide (2100) described below, the sharpness of the supply end (2110), the composition supply flow rate, the coolant heating amount, and the pressure of the coolant container (RC) are fixed, and the frozen particle size is measured after the freezing spray system (100) is operated, if the particle size is smaller than the lower limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the particle size of the frozen particle can be increased by lengthening the horizontal distance (HD) or designing the vertical distance (VD) to be long.

As another example, when the particle size determining factors such as the shape of the composition guide (2100) described below, the sharpness of the supply end (2110), the composition supply flow rate, the amount of coolant heating, and the pressure of the coolant container (RC) are fixed, and the frozen particle size is measured after the freezing spray system (100) is operated, if the particle size is larger than the upper limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the particle size of the frozen particle can be reduced by shortening the horizontal distance (HD) or designing the vertical distance (VD) to be short.

Fig. 14 is a diagram illustrating the sharpness of a supply terminal (2110) according to one embodiment. Referring to Fig. 14, the supply terminal (2110) has a first side (E1) and a second side (E2), and the first side (E1) and the second side (E2) meet at an intersection point (P) and form a specific angle. The smaller the angle formed by the first side (E1) and the second side (E2) at the supply terminal (2110), the higher the sharpness of the supply terminal (2110). For example, in (a) of FIG. 14, the first side (E1) and the second side (E2) of the supply end (2110) form a first angle (A1), and in (b) of FIG. 14, the first side (E1) and the second side (E2) of the supply end (2110) form a second angle (A2) which is smaller than the first angle (A1). The sharpness of the supply end (2110) is greater in (b) of FIG. 14 than in (a) of FIG.

Meanwhile, the shape of the supply end (2110) is not limited to the shape illustrated in FIG. 14, and the cross-section of the supply end (2110) may be a polygon such as a square or trapezoid in addition to a triangle, and the first side (E1) and the second side (E2) may be curved.

The higher the sharpness, the smaller the particle size of the frozen particles can be. Specifically, when the sharpness is small, as illustrated in (b) of FIG. 14, when the composition is deposited at the supply end (2110), the contact area (S2) between the supply end (2110) and the composition based on a certain distance (Z) from the intersection point (P) becomes smaller, and accordingly, the adhesive force between the composition and the supply end (2110) becomes smaller. When the adhesive force between the composition and the supply end (2110) becomes smaller, the detachment time taken for the composition to be detached from the supply end (2110) by the coolant particles becomes shorter, and since the amount of the composition deposited at the supply end (2110) is proportional to the detachment time, the composition is detached in a state where a smaller amount of the composition is deposited. That is, since a smaller amount of the composition is detached, the size of the composition droplets introduced into the coolant injection stream becomes smaller, and consequently, the particle size of the frozen particles also becomes smaller.

Conversely, the smaller the sharpness, the larger the particle size of the frozen particles can be. Specifically, as illustrated in (a) of FIG. 14, when the composition is deposited at the feed end (2110), the contact area (S1) between the feed end (2110) and the composition increases based on a certain distance (Z) from the intersection point (P), and accordingly, the adhesive force between the composition and the feed end (2110) increases. As the adhesive force between the composition and the feed end (2110) increases, the detachment time taken for the composition to be detached from the feed end (2110) by the coolant particles increases, and since the amount of the composition deposited at the feed end (2110) is proportional to the detachment time, the composition is detached in a state where a larger amount of the composition is deposited. That is, as a larger amount of the composition is detached, the size of the composition droplets introduced into the coolant injection stream increases, and consequently, the particle size of the frozen particles also increases.

As described above, the particle size of the frozen particles of the composition can be determined based on the sharpness of the feed end (2110). Accordingly, the sharpness of the feed end (2110) in the frozen spray system (100) is experimentally calculated so that the frozen particles have the aforementioned penetrable particle size, and the shape of the composition guide (2100) is designed based on the calculated value, and the composition guide (2100) can be manufactured based on the designed shape.

For example, when the freeze spray system (100) is operated and the freeze particle size is measured while the particle size determining factors such as the distance between the nozzle (1500) and the supply end (2110), the composition supply flow rate, the coolant heating amount, and the pressure of the coolant container (RC) are fixed, if the particle size is smaller than the lower limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the particle size of the freeze particle can be increased by designing the sharpness of the supply end (2110) to be small.

As another example, when the freeze spray system (100) is operated and the freeze particle size is measured while the particle size determining factors such as the distance between the nozzle (1500) and the supply end (2110), the composition supply flow rate, the coolant heating amount, and the pressure of the coolant container (RC) are fixed, if the particle size is larger than the lower limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the sharpness of the supply end (2110) can be designed to be large to reduce the particle size of the freeze particles.

Below, factors related to device control among the factors determining the particle size of frozen particles are described. In the freezing spray system (100), the amount of coolant heating (or the amount of thermal energy applied to the coolant) and the supply flow rate of the composition can be controlled. In addition, the pressure within the coolant container (RC) can be controlled in the freezing spray system (100).

The amount of coolant heating can be controlled by the heat providing unit (1300). For example, the heat providing unit (1300) includes a thermoelectric element, and the control unit (1900) of the coolant injection device (1000) can control the amount of power or current supplied to the thermoelectric element of the heat providing unit (1300) to adjust the amount of heat energy produced by the thermoelectric element.

The composition supply flow rate can be controlled by the actuator (2200). For example, when the actuator (2200) includes a piston and an electric motor, the control unit (1900) of the composition supply device (2000) or the control unit (1900) of the cooling spray device (1000) controls the amount of power or current supplied to the electric motor to adjust the strength of pressurizing the composition inside the composition container (CC), and accordingly, the composition flow rate supplied to the composition guide (2100) can be adjusted.

The pressure within the coolant container (RC) can be controlled by heating the coolant container (RC). Specifically, as the coolant container (RC) is heated and the temperature thereof increases, the pressure within the coolant container (RC) can increase. For example, the coolant injection device (1000) further includes a container heating unit configured to heat the coolant container (RC), and the heat energy produced by the container heating unit can be controlled by the control unit (1900). At this time, the container heating unit, like the heat providing unit (1300), includes a heat source and a heat transfer medium, and heat energy can be produced from the heat source and transferred to the coolant container (RC) through the heat transfer medium.

Meanwhile, the pressure inside the coolant container (RC) is determined by the pressure at which the coolant is charged into the coolant container (RC) and may not be separately controlled after charging.

The greater the amount of coolant heated, the smaller the particle size of the frozen particles can be. The greater the amount of coolant heated, the higher the temperature of the coolant spray stream formed by the nozzle (1500), and the higher the temperature, the longer the freezing time required for the composition introduced into the coolant spray stream to freeze. The longer the freezing time, the more often the composition is split by the coolant particles, and as the number of splits increases, the particle size of the frozen particles of the composition decreases.

Conversely, the smaller the coolant heating amount, the larger the particle size of the frozen particles. The smaller the coolant heating amount, the lower the temperature of the coolant spray stream formed by the nozzle (1500), and the lower the temperature, the shorter the freezing time of the composition introduced into the coolant spray stream. The shorter the freezing time, the fewer the number of times the composition is split by the coolant particles, and as the number of splits decreases, the particle size of the frozen particles of the composition increases.

As described above, the particle size of the frozen particles of the composition can be controlled by the amount of coolant heating. Accordingly, the range of control of the amount of coolant heating in the freezing spray system (100) is specified so that the frozen particles have the above-described penetrable particle size, and the control unit (1900) can control the heat supply unit (1300) so that the amount of coolant heating is within the specified control range.

For example, when the particle size determining factors such as the distance between the orifice of the supply end (2110) and the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the composition supply flow rate, and the pressure of the coolant container (RC) are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is smaller than the lower limit of the above-described penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the control unit (1900) can reset the signal value applied to the heat providing unit (1300) so as to decrease the coolant heating amount, thereby increasing the particle size of the freeze particles.

As another example, when the particle size determining factors such as the distance between the orifice of the supply end (2110) and the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the composition supply flow rate, and the pressure of the coolant container (RC) are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is larger than the upper limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the control unit (1900) can reset the signal value applied to the heat providing unit (1300) to increase the coolant heating amount, thereby reducing the particle size of the freeze particles.

As the composition supply flow rate increases, the particle size of the frozen particles can increase. As the composition supply flow rate increases, the contact area (e.g., S1 or S2 in FIG. 14) between the composition and the supply end (2110) when the composition is formed at the supply end (2110) increases, and as the contact area increases, the adhesive force between the composition and the supply end (2110) increases. As the adhesive force between the composition and the supply end (2110) increases, the force that the coolant particles exert on the composition must increase in order for the composition to be separated from the supply end (2110), which means that the separation time becomes longer. Since the amount of the composition formed at the supply end (2110) is proportional to the separation time and the composition supply flow rate, the composition is separated in a state where a larger amount of the composition is formed. That is, as a larger amount of the composition is separated, the size of the composition droplets that enter the coolant injection stream becomes larger, and consequently, the particle size of the frozen particles also becomes larger.

Conversely, the smaller the composition supply flow rate, the smaller the particle size of the frozen particles. The smaller the composition supply flow rate, the smaller the contact area (e.g., S1 or S2 in FIG. 14) between the composition and the supply end (2110) when the composition is formed at the supply end (2110), and as the contact area decreases, the adhesive force between the composition and the supply end (2110) decreases. As the adhesive force between the composition and the supply end (2110) decreases, the force that the coolant particles exert on the composition in order for the composition to be detached from the supply end (2110) must decrease, which means that the detachment time becomes shorter. Since the amount of the composition formed at the supply end (2110) is proportional to the detachment time and the composition supply flow rate, the composition is detached in a state where a smaller amount of the composition is formed. That is, as a smaller amount of the composition is detached, the size of the composition droplets entering the coolant injection stream becomes smaller, and consequently, the particle size of the frozen particles also becomes smaller.

As described above, the particle size of the frozen particles of the composition can be controlled by the composition supply flow rate. Accordingly, the flow rate range of the composition supply flow rate in the freezing spray system (100) is specified so that the frozen particles have the aforementioned penetrable particle size, and the actuator (2200) can be controlled by the control unit (1900) or the control unit included in the composition supply device (2000) so that the composition flow rate is within the specified flow rate range.

For example, when the particle size determining factors such as the distance between the supply end (2110) and the orifice of the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the amount of coolant heating, and the pressure of the coolant container (RC) are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is smaller than the lower limit of the above-described penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm or more and 80 µm or less), the control signal applied to the actuator (2200) is reset to increase the composition supply flow rate, so that the particle size of the freeze particles can be increased.

As another example, when the particle size determining factors such as the distance between the orifice of the supply end (2110) and the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the amount of coolant heating, and the pressure of the coolant container (RC) are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is larger than the upper limit of the above-mentioned penetrable particle size range (e.g., 16 ㎛ or more and 42 ㎛ or less or 10 ㎛ or more and 80 ㎛ or less), the control signal applied to the actuator (2200) can be reset to decrease the composition supply flow rate, so that the particle size of the freeze particles can be reduced.

The higher the pressure in the coolant container (RC), the smaller the particle size of the frozen particles. The higher the pressure in the coolant container (RC), the higher the velocity of the coolant particles within the coolant injection stream. This increased velocity of the coolant particles indicates an increase in the shear force or pressure applied to the composition introduced into the coolant injection stream, which can rapidly fragment the composition. Rapid fragmentation of the composition increases the number of fragments required before freezing, which can result in smaller frozen particles.

Additionally, when the coolant container (RC) is heated and pressurized, the temperature of the coolant injection stream increases, prolonging the freezing time for the composition to freeze. As the freezing time increases, the number of times the composition is fragmented by coolant particles increases before freezing, which can result in smaller frozen particles.

Conversely, a lower pressure in the coolant container (RC) may result in a larger particle size of the frozen particles. A lower pressure in the coolant container (RC) reduces the velocity of the coolant particles within the coolant spray stream. This decrease in the velocity of the coolant particles means a decrease in the magnitude of the shear force or pressure applied to the composition introduced into the coolant spray stream, which may result in slower fragmentation of the composition. Slower fragmentation of the composition reduces the number of fragmentations required before freezing, which may result in larger frozen particle sizes.

Additionally, when the coolant container (RC) is pressure-regulated by heating, the less heating is required to reduce the coolant container (RC) pressure, the lower the temperature of the coolant injection stream and the shorter the freezing time for the composition to freeze. As the freezing time is shortened, the number of times the composition is fragmented by coolant particles before freezing is reduced, which may result in larger frozen particles.

As described above, the particle size of the frozen particles of the composition can be controlled by the pressure of the coolant container (RC). Accordingly, the pressure range of the coolant container (RC) is specified so that the frozen particles have the aforementioned penetrable particle size, and the container heating unit can be controlled by the control unit (1900) so that the pressure of the coolant container (RC) is within the pressure range.

For example, when the particle size determining factors such as the distance between the orifice of the supply end (2110) and the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the amount of coolant heating, and the composition supply flow rate are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is smaller than the lower limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm to 80 µm), the control signal applied to the container heating unit is reset so that the amount of heating provided to lower the pressure inside the coolant container (RC) is reduced, so that the particle size of the freeze particles can increase.

As another example, when the particle size determining factors such as the distance between the orifice of the supply end (2110) and the nozzle (1500), the shape of the composition guide (2100) or the sharpness of the supply end (2110), the amount of coolant heating, and the composition supply flow rate are fixed, and the freeze particle size is measured after the freeze spray system (100) is operated, if the particle size is larger than the upper limit of the above-mentioned penetrable particle size range (e.g., 16 µm or more and 42 µm or less or 10 µm or more and 80 µm or less), the control signal applied to the container heating unit is reset to increase the amount of heating provided to increase the pressure inside the coolant container (RC), so that the particle size of the freeze particles can be reduced.

Hereinafter, a design method of a freeze spray system (100) for providing freeze particles with a desired particle size will be described with reference to FIGS. 15 and 16. The design method of the freeze spray system (100) is divided into a device (hardware) design method considering the sharpness of the supply end (2110) and the distance between the supply end (2110) and the nozzle (1500), and a control (software) design method considering the amount of coolant heating, the composition supply flow rate, and the coolant container pressure.

Fig. 15 is a flowchart showing a device design method of a freeze spray system (100) according to one embodiment.

Referring to FIG. 15, the device design method includes a step of setting a target particle size range (S2100), a step of specifying the sharpness of a supply end (2110) corresponding to the target particle size range (S2200), a step of designing a shape of a composition guide having the specified sharpness (S2300), a step of specifying a distance between the supply end (2110) and the orifice of a nozzle (1500) to correspond to the target particle size range (S2400), and a step of designing a position of the composition guide (2100) with respect to the nozzle (1500) to have the specified distance (S2500).

Each step is described in detail below.

First, a target particle size range can be set (S2100). The target particle size range can be set to the aforementioned penetrable particle size range. For example, the target particle size range can be set to 16 μm or more and 42 μm or less, or 10 μm or more and 80 μm or less. Meanwhile, the target impact velocity can be further considered in the design method of the freeze spray system (100).

For example, the freezing spray system (100) can be designed with a target particle size of 16 µm to 42 µm, which is the characteristic of the frozen particles that penetrated in the first experiment, and a target collision speed of 75 m/s to 110 m/s.

For another example, the freeze spray system (100) can be designed with a target particle size of 10 µm to 80 µm, which is a characteristic of the frozen particles that penetrated in the second experiment, and a target collision speed of 16 m/s to 48 m/s.

The sharpness of the supply end (2110) corresponding to the target particle size range can be specified (S2200). The sharpness of the supply end (2110) can be specified experimentally. For example, as described above, the freeze spray system (100) is arbitrarily designed, implemented, and operated, and then the particle size of the frozen particles is measured. If the measured particle size is greater than the upper limit of the target particle size range, the sharpness is increased. Conversely, if the measured particle size is less than the lower limit of the target particle size range, the sharpness is decreased. This process can be used to specify the sharpness.

The sharpness may be arbitrarily specified regardless of the target particle size range, and the target particle size range may be taken into account in the design process described below.

Meanwhile, before the sharpness of the supply end (2110) is specified, the viscosity (or viscosity range) of the composition to be used in the freeze spray system (100) may be specified. As described below, the particle size of the freeze particles may vary depending on the viscosity range of the composition, and the shape of the composition guide (2100) may be designed taking this into consideration. Specifically, after the viscosity of the composition to be used is specified, the sharpness of the supply end (2110) described above may be experimentally specified.

The shape of a composition guide (2100) having a specific sharpness can be designed (S2300). The composition guide (2100) can be designed to have a shape including a supply end (2110) having a specific sharpness. For example, the composition guide (2100) can have a shape in which a plate is folded at a specific angle and include two sides whose ends form an angle corresponding to the sharpness.

The distance between the supply end (2110) and the orifice of the nozzle (1500) can be specified to correspond to the target particle size range (S2400). Specifically, the horizontal distance (HD) and vertical distance (VD) described above can be specified considering the target particle size range.

For example, in a state where the composition guide (2100) is designed to have a specific sharpness, the freeze spray system (100) can be operated to measure the particle size, and the horizontal distance (HD) and the vertical distance (VD) can be specified by comparing the particle size with a target particle size range. Specifically, the values can be specified through a process of increasing the horizontal distance (HD) or increasing the vertical distance (VD) when the measured particle size is smaller than the lower limit of the target particle size range, and decreasing the horizontal distance (HD) or decreasing the vertical distance (VD) when the measured particle size is larger than the upper limit of the target particle size range.

The horizontal distance (HD) and vertical distance (VD) may be specified independently of the target particle size range. In this case, the target particle size range may be considered in the control design described below or the sharpness specification described above.

The position of the composition guide (2100) relative to the nozzle (1500) can be designed to have a specified distance (S2500). Specifically, the composition guide (2100) can be positioned such that the supply end (2110) has a specified horizontal distance (HD) and a specified vertical distance (VD) relative to the orifice of the nozzle (1500).

Meanwhile, steps S2100 to S2500 do not have to be performed in the order described, and steps S2400 and S2500 may be performed first, followed by steps S2200 and S2300.

Fig. 16 is a flowchart illustrating a control design method of a freeze injection system (100) according to one embodiment. The control design method assumes that the above-described step S2100 has been performed.

Referring to FIG. 16, the control design method may include a step of specifying a coolant heating amount range corresponding to a target particle size range (S3100), a step of setting a control signal to be applied to a heat provider (1300) based on the specified coolant heating amount range (S3200), a step of specifying a composition supply flow rate range corresponding to the target particle size range (S3300), a step of setting a control signal to be applied to an actuator (2200) based on the specified composition supply flow rate range (S3400), a step of specifying a pressure range within a coolant container (RC) corresponding to the target particle size range (S3500), and a step of setting a control signal to be applied to a container heating unit based on the specified pressure range (S3600).

Each step is described in detail below.

First, a range of coolant heating amounts corresponding to a target particle size range can be specified (S3100). Specifically, the range of heating amounts per unit time provided by the heat supply unit (1300) can be specified considering the target particle size range.

The coolant heating amount range can be specified by measuring the particle size of the frozen particles after implementing the freeze spray system (100) as described above and comparing the measured particle size with the target particle size range. The range of the coolant heating amount can be specified by increasing or decreasing the coolant heating amount so that the measured particle size is included in the target particle size range, and this has already been described and will therefore be omitted.

A control signal applied to the heat providing unit (1300) may be set based on a specified coolant heating amount range (S3200). Specifically, a current value or power value applied to the heat providing unit (1300) may be set so that the heating amount per unit time produced by the heat providing unit (1300) falls within the specified heating amount range. Here, the heat providing unit (1300) may be controlled by receiving a PWM (Pulse Width Modulation) control signal, and the PWM control signal may be set according to the set current value or power value.

A composition supply flow rate range corresponding to a target particle size range can be specified (S3300). Specifically, a range of composition supply flow rates to be supplied by the actuator (2200) can be specified considering the target particle size range.

The composition supply flow rate range can be specified by measuring the particle size of the frozen particles after implementing the freeze spray system (100) as described above and comparing the measured particle size with the target particle size range. The range of the composition supply flow rate can be specified by increasing or decreasing the composition supply flow rate so that the measured particle size is included in the target particle size range, and this has already been described and will therefore be omitted.

A control signal applied to the actuator (2200) may be set based on a specified composition supply flow rate range (S3400). Specifically, the control signal applied to the actuator (2200) may be set so that the pressure applied to the composition container (CC) from the actuator (2200) corresponds to the composition supply flow rate range.

A pressure range within a coolant container (RC) corresponding to a target particle size range can be specified (S3500). Specifically, the internal pressure range that the coolant container (RC) should have can be specified considering the target particle size range.

The coolant container pressure range can be specified by measuring the particle size of the frozen particles after implementing the freeze spray system (100) as described above and comparing the measured particle size with the target particle size range. The coolant container pressure range can be specified by increasing or decreasing the coolant container pressure so that the measured particle size is included in the target particle size range, and this has already been described and will be omitted.

A control signal applied to the container heating unit may be set based on a specified pressure range (S3600). Specifically, the control signal applied to the container heating unit may be set such that the amount of heat provided to the coolant container (RC) from the container heating unit ensures that the pressure within the coolant container (RC) falls within a specified pressure range.

Meanwhile, steps S3100 to S3600 do not have to be performed in the order described, and steps S3300 and S3400 may be performed first, followed by steps S3100 and S3200, and then steps S3500 and S3600. Alternatively, steps S3500 and S3600 may be performed first, followed by steps S3100 and S3200, and then steps S3300 and S3400.

Alternatively, any one of steps S3100 to S3600 may be omitted. For example, if the pressure of the coolant container (RC) is not controlled (e.g., if a container heating unit is not provided), steps S3500 and S3600 may be omitted. Alternatively, if the composition supply flow rate is not controlled, steps S3300 and S3400 may be omitted.

The control design method may additionally include a method for controlling the viscosity of the composition. Specifically, the control design method may further include a step of specifying a target viscosity (or target viscosity range) of the composition corresponding to a target particle size range, and a step of adjusting the viscosity of the composition based on the target viscosity.

The target viscosity of the composition can be specified by measuring the particle size of the frozen particles after implementing the freeze spray system (100) and comparing the measured particle size with the target particle size range. Specifically, the range of the composition viscosity can be specified through a process of increasing or decreasing the viscosity of the supplied composition so that the measured particle size is included in the target particle size range. At this time, if the measured particle size is greater than the upper limit of the target particle size range, the viscosity can be decreased, and conversely, if the measured particle size is less than the lower limit of the target particle size range, the viscosity can be increased.

The freeze spray system (100) may further include a configuration for controlling the viscosity of the composition. For example, the composition providing device (2000) may further include a viscosity control module, and the viscosity control module may be fluidly connected to the composition container (CC) and/or the composition guide (2100) to control the viscosity of the composition. The viscosity control module may control the viscosity of the composition by mixing a viscosity control agent, such as saline solution or xanthan gum, with the composition.

4. How to adjust penetration depth

In the above, the range of particle sizes of the penetrable frozen particles and the method for controlling the particle size were described with a focus on penetration of the composition into the skin.

Meanwhile, in the process of developing and commercializing a freeze-jet system (100) for composition penetration, controlling the penetration depth of the composition has emerged as a new challenge. Specifically, the penetration depth at which the composition must penetrate the skin surface may vary depending on the purpose of the composition's skin penetration or the type of composition, and accordingly, the penetration depth of the composition needs to be controlled.

For example, when a composition is applied to the skin for cosmetic purposes, the target cells of the composition may exist in the epidermis or the epidermal-dermal junction, and in this case, the composition may need to reach only the epidermis or the epidermal-dermal junction without reaching the dermis. Alternatively, when commercializing a cosmetic device using a freezing spray system (100), the product needs to be designed so that the composition reaches only the epidermis or the epidermal-dermal junction without reaching the dermis, for the safety of the recipient.

For example, a composition sprayed for cosmetic purposes on the face may have a thickness of 0.01 mm to 0.2 mm, 0.02 mm to 0.2 mm, 0.03 mm to 0.2 mm, 0.04 mm to 0.2 mm, 0.05 mm to 0.2 mm, 0.06 mm to 0.2 mm, 0.07 mm to 0.2 mm, 0.08 mm to 0.2 mm, 0.09 mm to 0.2 mm, 0.11 mm to 0.2 mm, 0.12 mm to 0.2 mm, 0.13 mm to 0.2 mm, 0.14 mm to 0.2 mm, 0.15 mm to 0.2 mm, 0.16 mm to 0.2 mm, 0.17 mm to 0.2 mm, 0.18 mm to 0.2 mm, 0.19 mm to It is desirable to reach a penetration depth of 0.2 mm, 0.01 mm to 0.1 mm, 0.02 mm to 0.1 mm, 0.03 mm to 0.1 mm, 0.04 mm to 0.1 mm, 0.05 mm to 0.1 mm, 0.06 mm to 0.1 mm, 0.07 mm to 0.1 mm, 0.08 mm to 0.1 mm, or 0.09 mm to 0.1 mm.

As another example, when a composition is penetrated into the skin for medical purposes, the target cells of the composition may exist in the dermis layer, and in this case, the particle size of the frozen particles of the composition needs to be specified to be greater than or equal to the lower limit of the particle size that can reach the dermis. The lower limit of the particle size that can reach the dermis is 30㎛, and the impact speed at this time may be greater than or equal to 100m/s. In addition, when a medical device using a freezing spray system (100) is commercialized, a clinical trial is required to obtain approval as a medical device, and in order to pass the clinical trial, the composition needs to consistently reach the dermis. If the clinical trial proves that the composition consistently reaches the dermis layer and that its therapeutic effect is proven, the product's competitiveness as a medical device can be enhanced.

Meanwhile, the viscosity of commercially available compositions varies. The applicant developed a freezing spray system (100) based on the premise of utilizing a commercially available composition, and discovered during development that the penetration depth may vary depending on the viscosity of the composition.

Specifically, it was confirmed that when spraying a composition using a freeze spray system (100), the penetration depth increases as the composition viscosity increases. In addition, it was confirmed that when the composition viscosity exceeds a certain value, the composition does not granulate, and thus, skin penetration does not occur smoothly.

The experiment was conducted as follows.

First, a target material was prepared by mixing and coagulating 5% (w/v) gelatin and 0.5% (w/v) calcium chloride (CaCl2), a substance similar to skin tissue.

A solution containing water, xanthan gum, and trypan blue was sprayed onto the prepared target material, and the viscosity of the spray solution was controlled by adjusting the ratio of xanthan gum for each case. In case 1, the viscosity of the spray solution was 28 cp, in case 2, the viscosity of the spray solution was 55 cp, in case 3, the viscosity of the spray solution was 136 cp, and in case 4, the viscosity of the spray solution was 271 cp.

In Cases 1 to 4, the spray solution was sprayed at a flow rate of 0.5 mL/min for 15 seconds, and after wiping the surface of the target material, the central part of the spray area was sliced to measure the penetration depth.

In cases 1 to 4, the aforementioned freezing spray system (100) was used to spray the solution. The aforementioned coolant spray device (1000) and the composition providing device (2000) according to the second embodiment were used.

As a control group (case 0), 0.125 mL of trypan blue was applied to the target material, rubbed, the surface of the target material was wiped, and the central part of the applied area was sliced to measure the penetration depth.

Figure 14 is a diagram illustrating the results of an experiment on the relationship between the viscosity and penetration depth of a composition according to one embodiment. Referring to Figure 14, as the viscosity of the composition increases, the penetration depth may increase. However, when the viscosity exceeds a certain value, the penetration depth may decrease. The decrease in penetration depth when the viscosity exceeds a certain value can be understood as being due to the composition not being granulated as described above.

Meanwhile, the compositions used in the freeze spray system (100) are commercially available compositions and may vary in viscosity. Despite the varying viscosity of the compositions, the penetration depth achieved by the compositions must be consistent, as described above, depending on the cosmetic or medical purpose. Accordingly, a penetration depth control method is needed to consistently control the penetration depth, as described below.

Hereinafter, a method for controlling the penetration depth will be described with reference to FIG. 15. The method for controlling the penetration depth is basically based on the premise of using a freeze spray system (100). In other words, the method for controlling the penetration depth can be understood as a method for controlling the penetration depth when spraying a composition by granulating and freezing it.

Meanwhile, penetration depth can be proportional to the particle size of the frozen particles. Specifically, the larger the particle size of the frozen particles, the greater the penetration depth. This is because the penetration depth is the distance the frozen particles travel after penetrating the skin and before melting. Larger frozen particles have a lower surface area-to-mass ratio, which reduces heat transfer and prolongs the melting time, thus lengthening the distance traveled, and thus the penetration depth.

Fig. 15 is a flowchart showing a method for controlling penetration depth considering target penetration depth and composition viscosity according to one embodiment.

Referring to FIG. 15, the penetration depth control method includes a step of confirming a target penetration depth and a composition viscosity (S4100), a step of selecting a control method corresponding to the target penetration depth and the composition viscosity (S4200), and a step of operating the freeze spray system (100) according to the selected control method (S4300).

Each step is described in detail below.

First, the target penetration depth and composition viscosity can be determined (S4100). The target penetration depth refers to a specific depth value or a specific depth range. Additionally, the composition viscosity refers to a specific viscosity value or a specific viscosity range.

The target penetration depth can be set by receiving input from the user. For example, the coolant spray device (1000) can output an interface that induces input of the target penetration depth through the output unit (1800), and can set the target penetration depth by receiving input from the user through the input unit (1700). At this time, the input for the target penetration depth can be in various forms, such as a specific value, a specific range, a target cell, a type of composition, or a body part to be penetrated by the composition, and the cryo-spray system (100) can set the target penetration depth corresponding to the input.

The target penetration depth can be set using a pre-stored value or pre-stored range. For example, when the freezing spray system (100) is used as a beauty device, the target penetration depth can be set to a value or range between 0.01 mm and 0.2 mm.

The composition viscosity can be set by receiving input from a user. For example, the coolant injection device (1000) can output an interface that induces input of the composition viscosity through the output unit (1800) and set the composition viscosity by receiving input from the user through the input unit (1700). At this time, the input for the composition viscosity can be in various forms, such as a specific value, a specific range, or a composition viscosity level, and the freeze injection system (100) can set the composition viscosity corresponding to the input.

The composition viscosity can be set based on a value obtained through a viscosity detection sensor. For example, the composition providing device (2000) includes a viscosity detection sensor mounted inside a composition container (CC) to detect the viscosity of the composition contained in the composition container (CC), and the composition viscosity can be set based on the value measured by the viscosity detection sensor.

A control method corresponding to the target penetration depth and composition viscosity can be selected (S4200). The freeze injection system (100) can operate using any one of a plurality of control methods. Each control method uses at least one of the coolant heating amount, the composition supply flow rate, and the pressure within the coolant container (RC) as a control variable, and the method for controlling the control variable may vary for each control method.

For example, according to the first control method, the heat providing unit (1300) is controlled so that the coolant heating amount becomes the heating amount per first unit time, and according to the second control method, the heat providing unit (1300) is controlled so that the coolant heating amount becomes the heating amount per second unit time, but the heating amount per first unit time may have a value smaller than the heating amount per second unit time.

When the target penetration depth is the same, a different control method may be selected depending on the composition viscosity confirmed in step S4100. Specifically, if the first control method is selected when the composition viscosity is confirmed as a first value, the second control method may be selected when the composition viscosity is confirmed as a second value smaller than the first value. This is because, since the penetration depth decreases when the composition viscosity decreases, it is necessary to compensate for this by increasing the particle size to increase the penetration depth in order to achieve the same target penetration depth, and since the particle size increases as the coolant heating amount decreases, the particle size is controlled to be larger in the second control method than in the first control method.

For another example, according to the third control method, the container heating unit is controlled so that the pressure inside the coolant container (RC) becomes the first pressure, and according to the fourth control method, the container heating unit is controlled so that the pressure inside the coolant container (RC) becomes the second pressure, but the first pressure may have a value lower than the second pressure.

When the target penetration depth is the same, a different control method may be selected depending on the composition viscosity confirmed in step S4100. Specifically, if the third control method is selected when the composition viscosity is confirmed as the first value, the fourth control method may be selected when the composition viscosity is confirmed as the second value smaller than the first value. This is because, since the penetration depth decreases when the composition viscosity decreases, it is necessary to compensate for this by increasing the particle size to increase the penetration depth in order to achieve the same target penetration depth, and since the particle size increases as the pressure inside the coolant container (RC) decreases, the particle size is controlled to be larger in the fourth control method than in the third control method.

For another example, the actuator (2200) is controlled so that the composition supply flow rate is the first flow rate according to the fifth control method, and the actuator (2200) is controlled so that the composition supply flow rate is the second flow rate according to the sixth control method, but the first flow rate may have a value smaller than the second flow rate.

When the target penetration depth is the same, a different control method may be selected depending on the composition viscosity confirmed in step S4100. Specifically, if the fifth control method is selected when the composition viscosity is confirmed as the first value, the sixth control method may be selected when the composition viscosity is confirmed as the second value smaller than the first value. This is because, since the penetration depth decreases when the composition viscosity decreases, it is necessary to compensate for this by increasing the particle size to increase the penetration depth in order to achieve the same target penetration depth, and since the particle size increases as the composition supply flow rate increases, the particle size is controlled to be larger in the sixth control method than in the fifth control method.

Meanwhile, in addition to the control method described above, a method of controlling the viscosity of the composition by considering the target penetration depth may also be used. For example, the target viscosity (or target viscosity range) of the composition may be specified based on the target penetration depth, the amount of coolant heating, the composition supply flow rate, and the coolant container (RC), and the viscosity of the composition may be controlled so that the viscosity of the composition becomes the target viscosity. To this end, the freeze spray system (100) includes the viscosity control module described above, and the viscosity control module may mix a viscosity control agent, such as saline or xanthan gum, with the composition to control the viscosity of the composition.

The freezing spray system (100) may operate according to the selected control method (S4300). Specifically, the control unit (1900) of the freezing spray system (100) may operate the coolant spray device (1000) and/or the composition providing device (2000) according to the control method selected in step S4200.

By using the penetration depth control method described above, a freeze spray system (100) can be implemented that provides a composition at a consistent penetration depth regardless of the viscosity of the composition used.

The features, structures, effects, etc. described in the embodiments above are included in at least one embodiment of the present specification, and are not necessarily limited to just one embodiment. Furthermore, the features, structures, effects, etc. exemplified in each embodiment can be combined or modified in other embodiments by a person skilled in the art to which the embodiments pertain. Therefore, the contents related to such combinations and modifications should be construed as being included within the scope of the present specification.

In addition, although the above description focuses on the embodiments, these are merely examples and do not limit the technical idea of the present specification, and those with ordinary skill in the art to which this specification pertains will recognize that various modifications and applications not exemplified above are possible without departing from the essential characteristics of the present embodiments. In other words, each component specifically shown in the embodiments can be modified and implemented. In addition, differences related to such modifications and applications should be interpreted as being included within the scope of the present specification defined in the appended claims.

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Claims (16)

In a freezing spray system that freezes a composition and sprays it to deliver the composition into the skin, Including a coolant injection device and a composition guide, The above composition guide guides the liquid composition to a position adjacent to the nozzle of the coolant injection device so that the liquid composition meets the coolant injected from the coolant injection device, The above coolant injection device injects a coolant toward the supply end of the composition guide from which the liquid composition flows out, so that the liquid composition is atomized into a plurality of liquid atomized particles by the injected coolant and some of the plurality of liquid atomized particles are cooled by the injected coolant and frozen into a plurality of solid frozen particles. Some of the plurality of solid frozen particles are characterized in that they have a particle size that can penetrate the stratum corneum of the skin before colliding with the skin and reach the inside of the skin by penetrating the stratum corneum of the skin by the composition guide and the coolant spraying device. Freeze spray system. In the first paragraph, The above nozzle has an orifice having a preset diameter, As the coolant passes through the orifice, a coolant injection stream is formed, The liquid composition formed at the supply end of the composition guide is separated from the supply end by the coolant injection stream and introduced into the coolant injection stream in the form of particles. Freeze spray system. In the second paragraph, The particle size of the plurality of solid frozen particles is determined according to the horizontal distance and vertical distance between the orifice of the nozzle and the supply end, The above horizontal distance is the distance between the orifice and the supply end in a direction parallel to the central axis of the nozzle, The above vertical distance is the distance between the orifice and the supply end in a direction perpendicular to the central axis of the nozzle. Freeze spray system. In the third paragraph, The smaller the horizontal distance, the smaller the particle size of the plurality of solid frozen particles. The smaller the vertical distance, the smaller the particle size of the plurality of solid frozen particles. Freeze spray system. In the first paragraph, The cross-section of the supply end of the above composition guide has a sharp shape with a width that narrows toward one side, The greater the degree to which the width of the above cross-section narrows, the greater the sharpness of the supply end. The particle size of the plurality of solid frozen particles is determined according to the sharpness of the supply end. Freeze spray system. In paragraph 5, The above supply end is characterized in that the larger the sharpness, the smaller the size of the plurality of solid frozen particles. Freeze spray system. In paragraph 6, As the sharpness of the supply end increases, the size of the plurality of liquid atomized particles decreases, and the particle size of the plurality of solid frozen particles decreases. Freeze spray system. In paragraph 5, The cross-section of the above supply end includes two line segments forming a preset angle, The smaller the preset angle, the smaller the particle size of the plurality of solid frozen particles. Freeze spray system. In the first paragraph, A composition storage unit in which the liquid composition is stored; and Further comprising a composition transfer pipe fluidly connecting the composition guide and the composition storage unit; The liquid composition moves from the composition storage unit to the composition guide through the composition transfer tube. Freeze spray system. In paragraph 9, Further comprising an actuator connected to the composition storage unit and controlling the flow rate of the liquid composition; The particle size of the plurality of solid frozen particles is determined according to the composition flow rate controlled by the actuator. Freeze spray system. In the first paragraph, The above coolant injection device further includes a coolant heating module configured to heat the coolant before the coolant is injected; The particle size of the plurality of solid frozen particles is determined according to the degree to which the coolant heating module heats the coolant. Freeze spray system. In Article 11, When the above coolant heating module is controlled to heat the coolant at a heating amount per first unit time, the particle size of the plurality of solid frozen particles is greater than that of the above coolant heating module. When the coolant heating module is controlled to heat the coolant at a second heating amount per unit time greater than the first heating amount per unit time, the particle sizes of the plurality of solid frozen particles have a smaller value. Freeze spray system. In the first paragraph, Further comprising a coolant container in which the coolant supplied to the coolant injection device is stored; The particle size of the plurality of solid frozen particles is determined according to the internal pressure of the coolant container. Freeze spray system. In the 13th paragraph, The smaller the internal pressure, the larger the particle size of the plurality of solid frozen particles. Freeze spray system. In any one of claims 1 to 14, The particle size of the above plurality of solid frozen particles is 16㎛ to 42㎛. Freeze spray system. In any one of claims 1 to 14, The particle size of the above plurality of solid frozen particles is 10㎛ to 80㎛. Freeze spray system.