HK1251163B - Emulsion cosmetic composition containing pigment powder and method for preparing same - Google Patents

Description

Emulsion cosmetic composition containing pigment powder and preparation method thereof

Technical Field

The present disclosure relates to an emulsion-type cosmetic composition comprising pigment powder and a method for preparing the same.

Background Art

When pigments used in water-in-oil cosmetic compositions are dispersed in the external phase, the pigments, present as powder, attack the emulsion interface, making it difficult to maintain emulsion stability. To address this issue, large amounts of thickeners are used to prevent the pigments dispersed in the external phase from coalescing and attacking the emulsion interface, thereby ensuring stable pigment dispersion and stabilizing the emulsion formulation. However, such thickeners can cause a sticky feel during use and make it difficult to achieve smooth spreadability due to their high viscosity.

Furthermore, water-in-oil formulations that excel in durability and water resistance contain oil as an external phase and are therefore not suitable for providing a refreshing feeling during use.

Spherical particles comprising a polymer have a controllable size and shape depending on their preparation method, and therefore have high applicability. For example, the contact angle (θ) between the aqueous phase and the oil phase of a Pickering emulsion formed using spherical particles varies depending on the hydrophilicity/hydrophobicity of the spherical particles. When the contact angle is greater than 90°, an O/W emulsion particle is formed. Meanwhile, when the contact angle is less than 90°, a W/O emulsion particle is formed.

Furthermore, some attempts have been made to impart amphiphilic properties (i.e., both hydrophilic and hydrophobic) to spherical microparticles in order to obtain new anisotropic powders. This is exemplified by Janus spherical particles. However, such spherical particles have limited chemical anisotropy due to their morphological limitations. In other words, although the particles are morphologically anisotropic, they can be either hydrophobic or hydrophilic overall and therefore have limited chemical anisotropy.

Therefore, several attempts have been made to obtain surface-active anisotropic powders by controlling their geometric shape and imparting chemical anisotropy. However, while such amphiphilic anisotropic powders have shown high applicability, methods for mass-producing them have yet to be developed. Furthermore, it is difficult to uniformly produce amphiphilic anisotropic powders in large quantities on an industrial scale, hindering their practical application.

Summary of the Invention

Technical issues

A technical problem to be solved by the present disclosure is to provide a stable emulsion-type cosmetic composition containing pigment powder.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition having excellent skin safety.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition that includes a pigment powder that is uniformly dispersed in the cosmetic composition without settling or coalescing and exhibits excellent formulation and emulsion stability.

Another technical problem to be solved by the present disclosure is to provide a makeup emulsion-type cosmetic composition having excellent long-lastingness and coverage effect.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition that provides a stable formulation without using an excessive amount of a thickener.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition that prevents skin irritation by avoiding the use of excessive amounts of thickeners, dispersants, surfactants, and the like.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition having excellent water resistance and long-lasting properties.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition that exhibits a refreshing feeling during use and a moist feeling due to the water-penetrating effect of the emulsion particles.

Another technical problem to be solved by the present disclosure is to provide an emulsion-type cosmetic composition that provides matte and powdery set feel.

Technical Solution

In one general aspect, provided is an emulsion-type cosmetic composition comprising an amphiphilic anisotropic powder and a pigment powder, wherein the amphiphilic anisotropic powder comprises first hydrophilic polymer spheroids and second hydrophobic polymer spheroids, the first polymer spheroids and the second polymer spheroids being bound to each other in a structure in which one polymer spheroid at least partially penetrates the other polymer spheroid, the first polymer spheroids having a core-shell structure, and the shell having a functional group.

Beneficial effects

In one aspect, the present disclosure provides a stable emulsion-type cosmetic composition comprising a pigment powder.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition having excellent skin safety.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition including a pigment powder that is uniformly dispersed in the cosmetic composition without settling or coalescing and exhibiting excellent formulation and emulsion stability.

In another aspect, the present disclosure provides a make-up emulsion-type cosmetic composition having excellent long-lastingness and coverage effects.

In another aspect, the present disclosure provides emulsion-type cosmetic compositions that provide stable formulations without the use of excessive amounts of thickeners.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition that prevents skin irritation by avoiding the use of excessive amounts of thickeners, dispersants, surfactants, and the like.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition having excellent water resistance and long-lasting properties.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition that exhibits a refreshing feeling in use and a moist feeling due to the water-penetrating effect of emulsion particles.

In another aspect, the present disclosure provides an emulsion-type cosmetic composition that provides a matte and powdery finish.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram illustrating the formation of an amphiphilic anisotropic powder according to one embodiment of the present disclosure.

FIG2 is an electron microscopic image of emulsion particles in the composition according to Example 1 (scale bar: 50 μm).

FIG3 is a photograph taken immediately after application of the composition according to Example 1. FIG.

FIG. 4 shows electron microscopic images of emulsion particles in the compositions according to Example 2 and Comparative Example 1, which were taken immediately after the compositions were prepared and 4 weeks after their preparation.

Best Practice

Some exemplary embodiments will now be described more fully below with reference to the accompanying drawings showing exemplary embodiments. However, the present disclosure can be embodied in a variety of different forms and should not be construed as being limited to the exemplary embodiments described therein. On the contrary, these embodiments are provided so that the present disclosure will be comprehensive and complete, and will fully convey the scope of the present disclosure to those skilled in the art. In these figures, the shapes, sizes, and areas of the figures may be magnified for clarity. In addition, although some of the components are shown for ease of description, those skilled in the art can easily understand the rest. In addition, it will be understood by those skilled in the art that various changes may be made to the form and details without departing from the scope of the present disclosure as defined by the appended claims.

As used herein, unless otherwise indicated, "substituted" means that at least one hydrogen atom of a functional group described herein is replaced by a halogen atom (F, Cl, Br or I), a hydroxyl group, a nitro group, an imino group (=NH, =NR, wherein R is a C1 to C10 alkyl group), an amidino group, a hydrazine or hydrazone group, a carboxyl group, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C30 heteroaryl group, or a substituted or unsubstituted C2 to C30 heterocycloalkyl group.

As used herein, "(meth)acryloyl" means acryloyl and/or methacryloyl.

As used herein, the particle size of the amphiphilic anisotropic powder is measured as the maximum length, which is the longest length of the powder particles. As used herein, the particle size ranges of the amphiphilic anisotropic powder mean that at least 95% of the amphiphilic anisotropic powder present in the composition falls within the corresponding range.

The average particle size of the emulsion particles used herein means the average value of the diameter of each particle. The average particle size range of the emulsion particles used herein means that at least 95% of the emulsion particles present in the composition fall within the corresponding range.

The average particle size of the pigment powder used herein means a volume average particle size obtained by calculating a volume average based on a particle size distribution determined by a known method for determining a particle size distribution (eg, observation of an electron microscope image, laser diffraction, etc.).

In one aspect, an emulsion-type cosmetic composition comprising a pigment powder and an amphiphilic anisotropic powder is provided. The composition comprises the pigment powder and can be used as a makeup cosmetic composition.

According to one embodiment, the pigment powder may be used in an amount of 0.001 wt % or more, 0.002 wt % or more, 0.003 wt % or more, 0.004 wt % or more, 0.005 wt % or more, 0.006 wt % or more, 0.007 wt % or more, 0.008 wt % or more, 0.009 wt % or more, 0.1 wt % or more, 0.2 wt % or more, 0.3 wt % or more, 0.4 wt % or more, 0.5 wt % or more, 0.6 wt % or more, 0.7 wt % or more, 0.8 wt % or more, 0.9 wt % or more, or 1 wt % based on the total weight of the composition. % or less, 8wt% or less, 7wt% or less, 6wt% or less, or 5wt% or less. For example, based on the gross weight of the composition, the pigment powder can be used in an amount of 0.001wt% to 30wt%, 0.1wt% to 20wt%, 0.5wt% to 10wt%, or 1wt% to 5wt%. Within the above range, the effect of improving skin texture and skin tone and excellent feeling during use can be provided, and a stable emulsion formulation can be maintained.

According to one embodiment of the present disclosure, a soft feeling in use may be provided while firmly maintaining the emulsion interface of emulsion particles by the amphiphilic anisotropic powder without coalescence of pigment powder.

According to another embodiment, the pigment powder is a conventional powder used to achieve the color of a cosmetic composition for makeup. For example, the pigment powder may comprise titanium dioxide zinc oxide talc, iron oxide mica, aluminum oxide polymethyl methacrylate, organic pigments and natural pigments.

According to another embodiment, when the pigment powder is present in the oil phase of the emulsion composition, the pigment powder may be treated with surface hydrophobization. The surface hydrophobization treatment may be performed using methods commonly used in the cosmetics field. For example, the pigment powder may be treated with silicone compounds, fatty acids, or amino acids, but is not limited thereto.

The average particle size of the pigment powder may be 0.001 μm or more, 0.005 μm or more, 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, 0.3 μm or more, 0.4 μm or more, 0.5 μm or more, 0.6 μm or more, 0.7 μm or more, 0.8 μm or more, 0.9 μm or more, 1 μm or more, 1.5 μm or more, 2 μm or more, 2.5 μm or more, 3 μm or more, 3.5 μm or more, 4 μm or more, 4.5 μm or more, or 5 μm or less; and 6 μm or less, 7 μm or less, 8 μm or less, 9 μm or less, 10 μm or less, 11 μm or less, 12 μm or less, 13 μm or less, 14 μm or less, 15 μm or less, 16 μm or less, 17 μm or less, 18 μm or less, 19 μm or less, 20 μm or less, 21 μm or less, 22 μm or less, 23 μm or less, 24 μm or less, 25 μm or less, 26 μm or less, 27 μm or less, 28 μm or less, 29 μm or less, or 30 μm or less. For example, the average particle size of the pigment powder may be 0.001 to 6 μm, particularly 0.3 to 6 μm. Within the above range, a makeup cosmetic composition having a coloring effect and excellent formulation stability can be provided.

According to another embodiment, the amphiphilic anisotropic powder includes first hydrophilic polymer spheroids and second hydrophobic polymer spheroids, wherein the first polymer spheroids and the second polymer spheroids are bound to each other in a structure in which one polymer spheroid at least partially penetrates the other polymer spheroid, the first polymer spheroids have a core-shell structure, and the shell has a functional group.

As used herein, a spheroid refers to a single body formed from a polymer, for example, having a spherical, globular, or ellipsoidal shape, and a major axis length in the micrometer or nanometer range based on the maximum length of the main body portion.

According to one embodiment, the core of the first polymer spheroid and the second polymer spheroid may include a vinyl polymer, and the shell of the first polymer spheroid may include a copolymer of a vinyl monomer and a functional group-containing monomer.

According to another embodiment, the vinyl polymer may comprise a vinyl aromatic polymer, in particular polystyrene.

According to another embodiment, the vinyl monomer may comprise a vinyl aromatic monomer.For example, the vinyl monomer may be a substituted or unsubstituted styrene.

According to another embodiment, the functional group may be siloxane.

According to another embodiment, the functional group-containing monomer can be a siloxane-containing (meth)acrylate, in particular at least one selected from the group consisting of 3-(trimethoxysilyl)propyl acrylate, 3-(trimethoxysilyl)propyl methacrylate, vinyltriethoxysilane and vinyltrimethoxysilane, or a combination thereof.

According to another embodiment, the shell of the polymer spheroid may also have hydrophilic functional groups introduced thereto.

According to another embodiment, the hydrophilic functional group may be a negatively charged or positively charged functional group or a polyethylene glycol (PEG)-based functional group and may include at least one selected from the group consisting of a carboxylate group, a sulfone group, a phosphate group, an amino group, an alkoxy group, an ester group, an acetate group, a polyethylene glycol group, and a hydroxyl group.

According to another embodiment, the shell of the first polymer spheroid may also have sugar-containing functional groups introduced thereto.

According to another embodiment, the sugar-containing functional group may be from at least one selected from the group consisting of N-{N-(3-triethoxysilylpropyl)aminoethyl}glucamide, N-(3-triethoxysilylpropyl)glucamide, and N-{N-(3-triethoxysilylpropyl)aminoethyl}-oligo-hyaluronic acid amide (N-{N-(3-)}-).

According to another embodiment, the amphiphilic anisotropic powder may have a symmetrical shape, an asymmetrical snowman shape, or an asymmetrical inverted snowman shape based on the bonding portion where the first polymer spheroids and the second polymer spheroids are bonded to each other. The snowman shape refers to first polymer spheroids and second polymer spheroids having different sizes bonded to each other.

According to another embodiment, the particle size of the amphiphilic anisotropic powder may be 100 to 2500 nm. In one variant, the particle size of the amphiphilic anisotropic powder may be 100 to 1500 nm, 100 to 500 nm, or 200 to 300 nm. In particular, the particle size of the amphiphilic powder may be 100 nm or more, 200 nm or more, 300 nm or more, 400 nm or more, 500 nm or more, 600 nm or more, 700 nm or more, 800 nm or more, 900 nm or more, 1000 nm or more, 1100 nm or more, 1200 nm or more, 1300 nm or more, 1400 nm or more, or 1500 nm or more; and 2500 nm or less, 2400 nm or less, 2300 nm or less, 2200 nm or more. or less, 1500 nm or less, 1400 nm or less, 1300 nm or less, 1200 nm or less, 1100 nm or less, 1000 nm or less, 900 nm or less, 800 nm or less, 700 nm or less, 600 nm or less, 500 nm or less, 400 nm or less, 300 nm or less, or 200 nm or less.

According to another embodiment, the amphiphilic anisotropic powder can form coarse emulsion particles having a size of 2 to 500 μm. In one variation, the amphiphilic anisotropic powder can form coarse emulsion particles having a size of 5 to 400 μm, 10 to 350 μm, 30 to 300 μm, or 50 to 300 μm. In particular, the amphiphilic anisotropic powder can form emulsion particles having a size of 2 μm or more, 3 μm or more, 4 μm or more, 5 μm or more, 6 μm or more, 7 μm or more, 8 μm or more, 9 μm or more, 10 μm or more, 11 μm or more, 12 μm or more, 13 μm or more, 14 μm or more, 15 μm or more, 16 μm or more, 17 μm or more, 18 μm or more, 19 μm or more, 20 μm or more, 21 μm or more, 22 μm or more 23μm or more, 24μm or more, 25μm or more, 26μm or more, 27μm or more, 28μm or more, 29μm or more, 30μm or more, 31μm or more, 32μm or more, 33μm or more, 34μm or more, 35μm or more, 36μm or more, 37μm or more, 38μm or more, 39μm or more, 40μm or more, 41μm or more, 42μm or more, 43μm or more, 44μm or more, 45μm or more , 46μm or greater, 47μm or greater, 48μm or greater, 49μm or greater, or 50μm or greater; and 500μm or less, 490μm or less, 480μm or less, 470μm or less, 460μm or less, 450μm or less, 440μm or less, 430μm or less, 420μm or less, 410μm or less, 400μm or less, 390μm or less, 380μm or less, 370μm or less, 360μm or less, 350μm or less or less, 340 μm or less, 330 μm or less, 320 μm or less, 310 μm or less, 300 μm or less, 290 μm or less, 280 μm or less, 270 μm or less, 260 μm or less, 250 μm or less, 240 μm or less, 230 μm or less, 220 μm or less, 210 μm or less, 200 μm or less, 190 μm or less, 180 μm or less, 170 μm or less, 160 μm or less, or 150 μm or less.

The hydrophobic and hydrophilic portions of the amphiphilic anisotropic powder have different orientations at the interface, resulting in coarse emulsion particles. These coarse emulsion particles enable the creation of emulsion formulations with a variety of viscosities, including formulations with a less sticky feel.

While conventional molecular-level surfactants form dynamic emulsions through interfacial films, amphiphilic anisotropic powders create interfacial films with emulsion particles that are hundreds of nanometers thick. Strong interparticle bonding creates a stabilized interfacial film, maintaining a stable emulsion state without being affected by pigment powder.

According to another embodiment, the amphiphilic anisotropic powder may be present in an amount of 0.1 wt % or more, 0.2 wt % or more, 0.3 wt % or more, 0.4 wt % or more, 0.5 wt % or more, 0.6 wt % or more, 0.7 wt % or more, 0.8 wt % or more, 0.9 wt % or more, or 1.0 wt % or more; and 20 wt % or less, 19 wt % or less, 18 wt % or less, 17 wt % or less, 16 wt % or less, 15 wt % or less, 14 wt % or less, 13 wt % or less, 12 wt % or less, 11 wt % or less, 10 wt % or less, 9 wt % or less, 8 wt % or less, 7 wt % or less, 6 wt % or less, 5 wt % or less, 4 wt % or less, or 3 wt % or less, based on the total weight of the composition. For example, the amphiphilic anisotropic powder may be present in an amount of 0.1 to 20 wt %, particularly 0.5 to 10 wt %, more particularly 1 to 4 wt %, and even more particularly 1 to 3 wt %, based on the total weight of the composition. Within the above range, stable emulsion particles can be formed and emulsion particles of an appropriate size can be formed.

The viscosity of the composition may be 1000 cps or greater, 1100 cps or greater, 1200 cps or greater, 1300 cps or greater, 1400 cps or greater, 1500 cps or greater, 1600 cps or greater, 1700 cps or greater, 1800 cps or greater, 1900 cps or greater, 2000 cps or greater, 2100 cps or greater, 2200 cps or greater, 2300 cps or greater, 2400 cps or greater, or 2500 cps or greater; and 3000 cps or greater. 0cps or less, 29000cps or less, 28000cps or less, 27000cps or less, 26000cps or less, 25000cps or less, 24000cps or less, 23000cps or less, 22000cps or less, 21000cps or less, 20000cps or less, 19000cps or less, 18000cps or less, 17000cps or less, 16000cps or less, 15000cps or less, 14000cps or less. cps or less, 13000cps or less, 12000cps or less, 11000cps or less, 10000cps or less, 8900cps or less, 8800cps or less, 8700cps or less, 8600cps or less, 8500cps or less, 8400cps or less, 8300cps or less, 8200cps or less, 8100cps or less, 8000cps or less, 7900cps or less, 7800cps or less, 7700cps or less cps or less, 7600 cps or less, 7500 cps or less, 7400 cps or less, 7300 cps or less, 7200 cps or less, 7100 cps or less, 7000 cps or less, 6900 cps or less, 6800 cps or less, 6700 cps or less, 6600 cps or less, 6500 cps or less, 6400 cps or less, 6300 cps or less, 6200 cps or less, 6100 cps or less, or 6000 cps or less. For example, the viscosity may be 1000 to 20,000 cps, 1000 to 10,000 cps, 1500 to 7000 cps, or 2000 to 6000 cps. The composition may form coarse emulsion particles having a stable emulsion interface. In addition, the pigment is dispersed in the oil phase, and a single amphiphilic anisotropic powder that does not form emulsion particles is also present to uniformly disperse the pigment powder without precipitation or coalescence. In addition, the formulation can have excellent emulsion stability.

A cosmetic composition according to one embodiment of the present disclosure may be obtained by a method including preparing an amphiphilic anisotropic powder, and emulsifying an oil phase part and a water phase part by using the amphiphilic anisotropic powder.

According to one embodiment, an amphiphilic anisotropic powder can be obtained by a method comprising: polymerizing a first monomer to obtain a core of a first polymer spheroid; coating the core of the first polymer spheroid to obtain a first polymer spheroid having a core-shell structure; and reacting the first polymer spheroid having a core-shell structure with a first monomer to obtain an amphiphilic anisotropic powder in which a second polymer spheroid is formed.

1 is a schematic diagram illustrating the formation of an amphiphilic anisotropic powder according to one embodiment of the present disclosure. The second polymer spheroid may be formed by allowing the core of the first polymer spheroid to pass through the shell of the first polymer spheroid and grow toward the outside by using the above method.

According to another embodiment, a method for preparing an amphiphilic anisotropic powder may include: (1) stirring a first monomer and a polymerization initiator to form a core of a first polymer spheroid; (2) stirring the formed core of the first polymer spheroid with a first monomer, a polymerization initiator, and a functional group-containing monomer to form a first polymer spheroid having a coated core-shell structure; and (3) stirring the formed first polymer spheroid having a core-shell structure with a second monomer and a polymerization initiator to obtain an anisotropic powder in which second polymer spheroids are formed.

In steps (1), (2), and (3), the stirring may be rotary stirring. Rotary stirring is preferred because uniform mechanical mixing and chemical modification are required to produce uniform particles. Rotary stirring can be performed in a cylindrical reactor, but is not limited thereto.

In this article, the internal design of the reactor significantly affects powder formation. The size and position of the baffles of the cylindrical reactor and the distance from the impeller have a significant impact on the uniformity of the particles to be produced. Preferably, the spacing between the internal blades and the impeller blades is minimized to make the convective flow and intensity uniform, the powdered reaction mixture is introduced to a level below the blade length, and the impeller is kept at a high rotation speed. The rotation speed can be 200 rpm or higher, and the ratio of the diameter to the height of the reactor can be 1-3: 1-5. In particular, the diameter of the reactor can be 10 to 30 cm, and the height can be 10 to 50 cm. The reactor can have a size that can be varied in proportion to the reaction capacity. In addition, the cylindrical reactor can be made of ceramic, glass, etc. Stirring is preferably carried out at a temperature of 50 to 90 ° C.

Simple mixing in a cylindrical rotary reactor allows the production of uniform particles, requires low energy consumption and provides maximized reaction efficiency, and is therefore suitable for mass production. Conventional tumbling methods involving the rotation of the reactor itself cause the entire reactor portion to tilt at a certain angle and rotation at high speed, and therefore require high energy consumption and limit reactor size. Due to such reactor size limitations, output is limited to a small amount of approximately tens of milligrams to several grams. Therefore, conventional tumbling methods are not suitable for mass production.

According to one embodiment, the first monomer and the second monomer may be the same or different, and in particular may be vinyl monomers. In addition, the first monomer added in step (2) may be the same as the first monomer used in step (1), and the initiators used in each step may be the same or different.

According to another embodiment, the vinyl monomer may be a vinyl aromatic monomer.The vinyl aromatic monomer may be a substituted or unsubstituted styrene.

According to another embodiment, the polymerization initiator can be a free radical polymerization initiator. In particular, the polymerization initiator can be a peroxide-based or azo-based initiator, or a combination thereof. In addition, ammonium persulfate, sodium persulfate or potassium persulfate can be used.

According to another embodiment, in step (1), the first monomer and the polymerization initiator may be mixed at a weight ratio of 100-1000: 1. In one variation, the first monomer and the polymerization initiator may be mixed at a weight ratio of 100-750: 1, 100-500: 1, or 100-250: 1.

In one variation, in step (1), a stabilizer is added together with the first monomer and polymerization initiator in such a manner that the first monomer, polymerization initiator, and stabilizer are mixed in a weight ratio of 100-1000:1:0.001-5. The size and shape of the powder are determined by controlling the size of the first polymer spheroids in step (1), and the size of the first polymer spheroids can be controlled by the ratio of the first monomer, initiator, and stabilizer. In addition, the uniformity of the anisotropic powder can be improved by mixing the first monomer, polymerization initiator, and stabilizer within the above ratio.

According to one embodiment, the stabilizer may be an ionic vinyl monomer, and in particular sodium 4-vinylbenzenesulfonate may be used. The stabilizer prevents particle swelling and imparts a positive or negative charge to the powder surface, thereby preventing electrostatic merging (bonding) of the particles.

When the size of the amphiphilic anisotropic powder is 200 to 250 nm, it can be obtained from first polymer spheres comprising the first monomer, initiator, and stabilizer in a ratio of 110-130:1:2-4 (and particularly 115-125:1:2-4).

Furthermore, when the size of the amphiphilic anisotropic powder is 400 to 450 nm, it can be obtained from first polymer spheres comprising the first monomer, initiator, and stabilizer in a ratio of 225-240:1:1-3 (and particularly 230-235:1:1-3).

Furthermore, when the size of the amphiphilic anisotropic powder is 1100 to 2500 nm, it can be obtained from first polymer spheroids prepared by reacting a first monomer, an initiator, and a stabilizer at a ratio of 110-130:1:0 (particularly 115-125:1:0).

Furthermore, the amphiphilic anisotropic powder having an asymmetric snowman shape can be obtained from first polymer spheres prepared by reacting a first monomer, an initiator, and a stabilizer in a ratio of 100-140:1:8-12 (particularly 110-130:1:9-11).

Furthermore, the amphiphilic anisotropic powder having an asymmetric inverted snowman shape can be obtained from first polymer spheres prepared by reacting a first monomer, an initiator, and a stabilizer in a ratio of 100-140:1:1-5 (particularly 110-130:1:2-4).

According to another embodiment, the functional group-containing monomer in step (2) can be a siloxane-containing (meth)acrylate, such as 3-(trimethoxysilyl)propyl acrylate, 3-(trimethoxysilyl)propyl methacrylate, vinyltriethoxysilane, vinyltrimethoxysilane, or a combination thereof.

According to another embodiment, in step (2), the first monomer, the polymerization initiator and the functional group-containing compound can be mixed in a weight ratio of 80-98:0.2-1.0:2-20. In one variation, the first monomer, the polymerization initiator and the functional group-containing compound can be mixed in a weight ratio of 160-200:1:6-40. The degree of coating can be controlled according to the reaction ratio, and the degree of coating then determines the shape of the amphiphilic anisotropic powder. When the first monomer, the polymerization initiator and the functional group-containing compound are used within the above ratio, the coating thickness is increased by about 10% to 30%, in particular about 20%, based on the initial thickness. In this case, the powder formation proceeds smoothly without problems such as the inability to form powder due to excessively thick coating or the multi-directional formation of powder due to excessively thin coating. In addition, the uniformity of the anisotropic powder can be improved within the above weight ratio.

In step (3), the core of the first polymer spheroid passes through the shell from one direction of the first polymer spheroid having a core-shell structure and protrudes outward from the shell. Then, the protrusion can be formed into the shape of anisotropic powder by polymer growth of the second monomer.

According to another embodiment, in step (3), the second monomer and the polymerization initiator may be mixed in a weight ratio of 150-250: 1. In one variation, the second monomer and the polymerization initiator may be mixed in a weight ratio of 160-250: 1, 170-250: 1, 180-250: 1, 190-250: 1, 200-250: 1, 210-250: 1, 220-250: 1, 230-250: 1, or 240-250: 1.

In one variation, in step (3), a stabilizer may be added together with the second monomer and the polymerization initiator in such a manner that the second monomer, the polymerization initiator, and the stabilizer are mixed in a weight ratio of 150-250:1:0.001-5. Specific examples of the stabilizer are the same as those described above. The above weight ratio can improve the uniformity of the anisotropic powder.

According to another embodiment, in step (3), the second monomer can be mixed in an amount of 40 to 300 parts by weight based on 100 parts by weight of the first polymer spheroid having a core-shell structure. In particular, when the content of the second monomer is 40% to 100% based on the weight of the first polymer spheroid, an asymmetric snowman-like powder is obtained. When the content of the second monomer is 100% to 150% or 110% to 150% based on the weight of the first polymer spheroid, a symmetrical powder is obtained. In addition, when the content of the second monomer is 150% to 300% or 160% to 300% based on the weight of the first polymer spheroid, an asymmetric inverted snowman-like powder is obtained. The uniformity of the anisotropic powder can be improved within the above-mentioned weight ratio.

According to another embodiment, after step (3), the method for preparing an amphiphilic anisotropic powder may further comprise the step (4) of introducing hydrophilic functional groups into the anisotropic powder.

According to another embodiment, the hydrophilic functional group in step (4) can be introduced by using a silane coupling agent and a reaction modifier, but is not limited thereto.

According to another embodiment, the silane coupling agent may be at least one selected from the group consisting of N-[(3-(trimethoxysilyl)propyl)ethylenediamine, N-[3-(trimethoxysilyl)propyl]ethylenediammonium chloride, (N-succinyl-3-aminopropyl)trimethoxysilane, 1-[3-(trimethoxysilyl)propyl]urea, and 3-[(trimethoxysilyl)propoxy]-1,2-propanediol. In particular, the silane coupling agent may be N-[(3-(trimethoxysilyl)propyl)ethylenediamine.

According to another embodiment, the silane coupling agent may be mixed in an amount of 35 to 65 parts by weight (particularly 40 to 60 parts by weight) based on 100 parts by weight of the anisotropic powder obtained in step (3). Hydrophilization can be sufficiently performed within the above range.

According to another embodiment, the reaction modifier may be ammonium hydroxide.

According to another embodiment, the reaction modifier may be mixed in an amount of 85 to 115 parts by weight (particularly 90 to 110 parts by weight) based on 100 parts by weight of the anisotropic powder obtained in step (3). Hydrophilization can be sufficiently performed within the above range.

According to another embodiment, after step (3), the method for preparing an amphiphilic anisotropic powder may further comprise the step (4) of introducing sugar-containing functional groups into the anisotropic powder.

In step (4), the sugar-containing functional group may be introduced by using a sugar-containing silane coupling agent and a reaction modifier, but is not limited thereto.

According to another embodiment, the sugar-containing silane coupling agent may be at least one selected from the group consisting of N-{N-(3-triethoxysilylpropyl)aminoethyl}glucamide, N-(3-triethoxysilylpropyl)glucamide, and N-{N-(3-triethoxysilylpropyl)aminoethyl}-oligo-hyaluronic acid amide.

According to another embodiment, the reaction modifier may be ammonium hydroxide.

According to another embodiment, the reaction modifier may be mixed in an amount of 85 to 115 parts by weight (particularly 90 to 110 parts by weight) based on 100 parts by weight of the anisotropic powder obtained in step (3). Within the above range, the sugar-containing functional group can be sufficiently introduced.

The method disclosed herein for preparing anisotropic amphiphilic powders does not use a crosslinking agent, thus preventing agglomeration and providing high yield and uniformity. Furthermore, the method disclosed herein utilizes a simple stirring process and is more suitable for mass production compared to tumbling processes. In particular, the method disclosed herein is advantageous in that it allows for the large-scale production of nanosized particles of 300 nm or less in quantities of tens of grams and kilograms.

According to another embodiment, the emulsion composition can be a water-in-oil emulsion composition. In particular, the water-in-oil (W/O) emulsion composition can be a conventional water-in-oil (W/O) emulsion composition or a water-in-silicone (W/S) emulsion composition in which silicone oil forms the external phase. For example, the composition can be a water-in-oil composition.

When the composition is a water-in-oil type or water-in-silicone type composition, the pigment powder is present in the oil phase as the external phase and thus can be stably dispersed without precipitation or coalescence of the pigment particles as described above.

Water-in-oil or water-in-silicone emulsion compositions have an oil phase as their external phase, and therefore exhibit excellent water resistance and long-lasting properties. Depending on the composition, the large particles in the internal phase are expelled upon application to the skin, providing a refreshing feeling through water seepage. This avoids the sticky feeling or discomfort that can occur when the external phase is an oil phase.

Unlike conventional water-in-oil compositions, compositions according to one embodiment of the present disclosure may not be sticky or rigid formulations, but may instead form formulations with a characteristic feel resulting from the water permeation of large powder emulsion particles. The composition may form coarse emulsion particles with a rigid emulsion interface, wherein the pigment powder is dispersed in the oil phase and a single amphiphilic anisotropic powder that does not form emulsion particles may also be present. Consequently, the pigment powder can be uniformly dispersed without settling or coalescence. Furthermore, a formulation with excellent emulsion stability can be provided.

In the composition according to one embodiment of the present disclosure, the pigment powder can be uniformly dispersed without using a high content of a thickener, thereby preventing a sticky feeling or skin irritation caused by a thickener.

The composition according to one embodiment of the present disclosure easily undergoes formulation disintegration when applied to the skin, thereby providing a use feeling with smooth spreadability.

The composition according to one embodiment of the present disclosure can prevent skin irritation that may occur due to the addition of a dispersant or an excess of a surfactant.

The composition according to one embodiment of the present disclosure exhibits excellent emulsion stability even when containing pigment powder, and thus can simultaneously provide a soft feel as an emulsion composition and a refreshing and moist feeling derived from water penetration. In particular, the composition exhibits the above-mentioned effects while maintaining its stability even in the presence of a high content of pigment powder.

The composition according to one embodiment of the present disclosure can avoid the sticky makeup setting feeling caused by surfactants. In addition, a formulation with a matte and powdery makeup setting feeling can be provided by virtue of the presence of an amphiphilic anisotropic powder that does not form emulsion particles.

The composition according to one embodiment of the present disclosure exhibits emulsion stability over time in a wide temperature range, for example, temperatures from -15°C to 60°C, particularly from -10°C to 55°C.

The composition according to one embodiment of the present disclosure comprises coarse emulsion particles to provide a soft and silky feel in use.

In the composition according to one embodiment of the present disclosure, water seepage occurs to a degree visible to the naked eye, and the inner phase of the coarse emulsion particles is immediately expelled upon application. In this manner, the composition supplies water to the skin, exhibits a skin texture-adjusting effect, imparts color through the pigment powder, covers skin tones or textures, provides a matte and close-fitting feel thanks to the powdery and light feel produced by the amphiphilic anisotropic powder, and maintains long-lasting effect.

The composition according to one embodiment of the present disclosure can maintain emulsion formulation stability even when it additionally includes excess ethanol or salt to provide a formulation with a refreshing feel.

The composition according to one embodiment of the present disclosure can be formulated by incorporating therein a cosmetically or dermatologically acceptable medium or matrix. Such formulations include any formulation suitable for topical application and can be provided in the form of a suspension, microemulsion, microcapsule, microparticle or ionic (liposome) and non-ionic vesicular dispersion, or in the form of a cream, thin layer lotion, powder, ointment, spray or concealer stick. In addition, the composition can be used in the form of a foam or aerosol composition further comprising a pressurized propellant. Such compositions can be obtained by methods known to those skilled in the art.

The composition according to one embodiment of the present disclosure may be formulated as a cosmetic composition such as a foundation, a liquid foundation, a concealer, or a primer, but is not limited thereto.

The composition according to an embodiment of the present disclosure may include supplementary ingredients conventionally used in cosmetics or dermatology, such as powders, fatty substances, organic solvents, solubilizers, concentrates, gelling agents, softeners, antioxidants, suspending agents, stabilizers, foaming agents, fragrances, surfactants, water, ionic or nonionic emulsifiers, fillers, metal ion chelating agents, chelating agents, preservatives, vitamins, protective agents, wetting agents, essential oils, dyes, pigments, hydrophilic or lipophilic activators, lipid vesicles or any other ingredients conventionally used in cosmetics. Such supplementary ingredients are introduced in amounts commonly used in cosmetics or dermatology. The composition according to an embodiment of the present disclosure may also include a skin absorption accelerator to improve the effect of improving skin condition.

DETAILED DESCRIPTION

Examples will now be described to illustrate the present disclosure in detail. It should be understood by those skilled in the art that the following examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure.

[Preparation Examples 1 to 4]

Preparation Examples 1 to 4 were obtained according to the compositions of the following Table 1. The preparation methods will be described below.

The ingredients used in Preparation Examples 1 to 4 are shown below.

[Table 1]

MeOH: methanol (co-solvent)

KPS: Potassium persulfate (initiator)

SVBS: Sodium vinylbenzenesulfonate (stabilizer)

PS: Polystyrene (polymer beads)

CS: coated first polymer spheroids with core-shell structure

DB: amphiphilic anisotropic powder

TMSPA: Trimethoxysilylpropyl acrylate (functional group)

AIBN: Azobisisobutyronitrile (polymerization initiator)

Preparation Example 1. Preparation of polystyrene (PS) first polymer spheres

First, 50 g of styrene as a monomer, 1.0 g of sodium 4-vinylbenzenesulfonate as a stabilizer, and 0.5 g of azobisisobutyronitrile (AIBN) as an initiator were mixed in an aqueous phase and reacted at 75° C. for 8 hours. The reaction was carried out by stirring the reaction mixture at a speed of 200 rpm in a cylindrical reactor made of glass having a diameter of 11 cm and a height of 17 cm.

Preparation Example 2. Preparation of coated first polymer spheroids having a core-shell (CS) structure

First, 300 g of the polystyrene (PS) first polymer spherical particles obtained as described above were mixed with 50 g of styrene as a monomer, 6 g of 3-(trimethoxysilyl)propyl acrylate (TMSPA), and 0.2 g of azobisisobutyronitrile (AIBN) as an initiator, and the reaction mixture was reacted at 75° C. for 8 hours. The reaction was carried out by stirring the reaction mixture in a cylindrical reactor.

Preparation Example 3. Preparation of amphiphilic anisotropic powder (DB)

First, 240 g of an aqueous dispersion of the polystyrene core-shell (PC-CS) dispersion obtained above was mixed with 40 g of styrene as a monomer, 0.35 g of sodium 4-vinylbenzenesulfonate as a stabilizer, and 0.2 g of azobisisobutyronitrile (AIBN) as an initiator. The reaction mixture was heated to 75°C for 8 hours. The reaction was carried out by stirring the reaction mixture in a cylindrical reactor. In this way, an amphiphilic anisotropic powder was obtained.

Preparation Example 4. Preparation of hydrophilized amphiphilic anisotropic powder

First, 600 g of the aqueous dispersion of the anisotropic powder obtained as described above was mixed with 30 g of N-[3-(trimethoxysilyl)propyl]ethylenediamine as a silane coupling agent and 60 g of ammonium hydroxide as a reaction modifier, and the reaction mixture was reacted at 25° C. for 24 hours to introduce a hydrophilic functional group. The reaction was carried out by stirring the reaction mixture in a cylindrical reactor to obtain a hydrophilized amphiphilic anisotropic powder.

[Examples and Comparative Examples] Preparation of emulsion compositions

Water-in-oil emulsion compositions of Examples 1 and 2 and Comparative Example 1 were prepared according to the compositions of Tables 2 and 3 below. Examples 1 and 2 are emulsion compositions obtained by using the amphiphilic anisotropic powder prepared according to Preparation Example 3, and Comparative Example 1 is an emulsion composition using a conventional surfactant.

Specifically, the pigment was dispersed in the oil phase portion formed by mixing the oil phase components of Tables 2 and 3 at 3500 rpm for 5 minutes, and the aqueous phase components formed by stirring and mixing were added thereto. Then, emulsification was performed at 3500 rpm for 10 minutes, and a thickener was added to thicken the mixture at 3500 rpm for 5 minutes, followed by cooling and degassing.

The components used in the following Examples and Comparative Examples are shown below.

(a) Oil:

Butylene Glycol Dicaprylate/Dicaprate (Dermofeel BGC, SASOL)

Dicaprylyl carbonate (Cetiol CC, Cere Chemicals (Henkel))

Cyclopentasiloxane, cyclohexasiloxane (Dow Corning 345 Fluid, Dow Corning)

(b) Oil-dispersed amphiphilic anisotropic powder: An oil-dispersed solution was obtained by dispersing the amphiphilic anisotropic powder of Preparation Example 3 in decamethylcyclopentasiloxane (DC 345, Dow Corning) to 13 wt % based on the total solution of the oil-dispersed solution.

(c) Pigment powder:

Titanium dioxide/triethoxycaprylylsilane (OTS coating pigment, OTS-2 TIO2 CR-50, DAITO KASEI KOGYO CO., LTD., 0.45 μm)

Iron oxide/triethoxycaprylylsilane (OTS coating pigment, OTS-2 Yellow LLXLO, DAITO KASEI KOGYO CO., LTD., 0.6 μm)

Iron oxide/triethoxycaprylylsilane (OTS coating pigment, OTS-2 Red R-516L, DAITO KASEI KOGYO CO., LTD., 1.1 μm)

Iron oxide/triethoxycaprylylsilane (OTS coating pigment, OTS-2 Black BL-100, DAITO KASEI KOGYO CO., LTD., 2.5 μm)

Polymethyl methacrylate (Artpearl K-7P, Donjin Chemical Co. Ltd., 6.0 μm)

(d) Preservative: Phenoxyethanol (Clariant)

(e) Softener: Ethylhexylglycerin (Sensiva SC50, Schülke & Mayr)

(f) Moisturizer: Butylene glycol (Daicel)

(g) Metal ion chelating agent: EDTA (E.D.T.A.-2NA, Neord Co., Ltd.)

(h) Emulsion stabilizer: sodium chloride

(i) Inorganic thickener: Bentonite (Bentone 38V, Elementis Specialties, Inc.)

(j) Surfactant: PEG-10 dimethicone (KF-6017, Shinetsu Silicone)

[Table 2]

[Table 3]

[Test Example 1] Observation results of the preparation and the effect after initial application

The composition of Example 1 was observed with an electron microscope, and its image is shown in Figure 2. Water seepage was also observed during the initial application. An image illustrating the initial application is shown in Figure 3.

As can be seen from Figure 2, coarse emulsion particles are stably formed. As can be seen from Figure 3, when the coarse emulsion particles burst during application, the aqueous phase components of the internal phase are discharged, thereby generating water droplets to a degree visible to the naked eye.

[Test Example 2] Evaluation of emulsion stability over time

The compositions of Example 2 and Comparative Example 1 were allowed to stand at 30°C for 4 weeks to determine the emulsion stability of each formulation. Figure 4 shows electron micrographs of the compositions immediately after preparation and after 4 weeks. As can be seen from Figure 4, Example 2 formed coarse emulsion particles and maintained the emulsion particles stably for a long period without any change. However, in the case of Comparative Example 1, which used a conventional surfactant, the initial emulsion particles were formed to a small size, and after 4 weeks, the emulsion particles became larger due to merging of the emulsion particles, resulting in a decrease in emulsion stability.

[Test Example 3] Evaluation of Usage

Thirty female panelists in their twenties to forties were asked to apply each of the cosmetic compositions obtained in Comparative Example 1 and Example 2. The panelists then evaluated the moisturizing feel, refreshing setting, stickiness, and watery appearance upon application on a five-point scale (1: very low to 5: very high). The results are shown as average values in Table 4 below.

[Table 4]

Evaluation Project Example 2 Comparative Example 1 Hydrating feeling 4.5 3.0 Refreshing makeup setting feeling 4.2 2.8 Viscosity 2.9 3.6 Water seepage appearance Visible water droplets No water drops seen

As shown in Table 4, Example 2 exhibited excellent moistness, a light setting feel, low viscosity, and water droplets due to water seepage. However, Comparative Example 1 exhibited insufficient moistness, a light setting feel, high viscosity, and no water droplets.

Claims (16)

1. An emulsion-type cosmetic composition comprising amphiphilic anisotropic powder and pigment powder, The amphiphilic anisotropic powder comprises a first hydrophilic polymer sphere and a second hydrophobic polymer sphere. The first hydrophilic polymer sphere and the second hydrophobic polymer sphere are bonded to each other in such a structure that one polymer sphere at least partially penetrates the other polymer sphere, and The first hydrophilic polymer sphere has a core-shell structure, and the shell has functional groups. The amphiphilic anisotropic powder described herein does not contain crosslinking. The amount of the pigment powder is 1 to 30 wt% based on the total weight of the composition. The composition is either a water-in-oil composition or a water-in-silicone composition. The pigment is dispersed in the outer phase of the water-in-oil composition or the silicone water-in-oil composition. The pigment powder contains at least one selected from the following: titanium dioxide, zinc oxide, talc, iron oxide, mica, alumina, and polymethyl methacrylate. The pigment powder has an average particle size of 0.001 to 6 μm, and The core of the first hydrophilic polymer sphere and the second hydrophobic polymer sphere comprise vinyl polymers, and the shell of the first hydrophilic polymer sphere comprises a copolymer of vinyl monomers and functionalized monomers. 2. The composition according to claim 1, wherein, based on the total weight of the composition, it comprises 0.1 to 20 wt% of the amphiphilic anisotropic powder. 3. The composition according to claim 1, wherein the viscosity is 1000 to 20000 cps. 4. The composition according to claim 1, wherein the pigment is surface-hydrophobicated. 5. The composition according to claim 1, wherein the functional group is a siloxane. 6. The composition according to claim 1, wherein the vinyl polymer is a vinyl aromatic polymer. 7. The composition according to claim 1, wherein the vinyl monomer is a vinyl aromatic monomer. 8. The composition according to claim 1, wherein the functionalized monomer is a siloxane-containing (meth)acrylate. 9. The composition according to claim 1, wherein, based on the bonding portion where the first hydrophilic polymer spheres and the second hydrophobic polymer spheres are bonded together, the amphiphilic anisotropic powder has a symmetrical shape or an asymmetrical shape of the first hydrophilic polymer spheres and the second hydrophobic polymer spheres bonded together and having different sizes. 10. The composition according to claim 1, wherein the particle size of the amphiphilic anisotropic powder is 100 to 2500 nm. 11. The composition according to claim 1, wherein the amphiphilic anisotropic powder forms coarse emulsion particles with an average particle size of 50 to 300 μm. 12. The composition of claim 1, wherein the shell of the first hydrophilic polymer sphere comprises additionally introduced hydrophilic functional groups thereto. 13. The composition according to claim 12, wherein the hydrophilic functional group is selected from at least one of the following: carboxyl group, sulfone group, phosphate group, amino group, alkoxy group, ester group, polyethylene glycol group, and hydroxyl group. 14. The composition according to claim 13, wherein the carboxylate group is an acetate group. 15. The composition of claim 1, wherein the shell of the first hydrophilic polymer sphere comprises sugar-containing functional groups further introduced thereto. 16. The emulsion-type cosmetic composition according to claim 15, wherein the sugar-containing functional group is selected from at least one of: N-{N-(3-triethoxysilylpropyl)aminoethyl}glucamide, N-(3-triethoxysilylpropyl)glucamide and N-{N-(3-triethoxysilylpropyl)aminoethyl}-oligomeric-hyaluronic acid amide.