HK40042685B - Moisturizing cream and lotion - Google Patents

Description

Moisturizing cream and lotion

Technical Field

This invention relates to a personal care composition with excellent moisturizing, smoothing and exfoliation properties.

Background of the Invention

Moisturizers are mixtures of chemical agents specifically designed to soften the outer layer of skin or hair. Personal care compositions with moisturizing properties are known. Consumers expect such compositions to meet a range of requirements. In addition to determining the intended skin/hair care effects, values are set for various parameters such as dermatological compatibility, appearance, sensory impression, storage stability, and ease of use.

U.S. Patent 20150190321 granted to Cognis discloses a mixture of monoalkyl ethers and dialkyl ethers of glycerol in a weight ratio of 1:1 to 1.3:1 having the emulsifying properties and consistency-imparting properties disclosed therein.

U.S. Patent Publication 20100297044, granted to Cognis, discloses an emulsifier mixture comprising (a) 0.1% to 60% by weight of a fatty alcohol or a mixture of fatty alcohols, (b) 30% to 97% by weight of an ethoxylated fatty alcohol or a mixture of ethoxylated fatty alcohols, (c) 0.1% to 20% by weight of a dialkyl (alkenyl) ether, a dialkyl (alkenyl) carbonate, or a mixture of these components, and (d) less than 10% by weight of water.

U.S. Patent 8,765,967, granted to DSM, discloses a sunscreen composition comprising (i) cosmetic auxiliaries and additives and (ii) microcapsules with UV-filtering activity prepared by a sol-gel method. This reference discloses a sol-gel method comprising emulsifying a crosslinkable monomer (preferably a silane with and without UV-filtering activity) under high shear stress in an aqueous solution containing surfactants such as hexadecyltrimethylammonium chloride that help stabilize the emulsion and/or protective colloids such as PVP (polyvinylpyrrolidone), PVA (polyvinyl alcohol), etc.

U.S. Patent 6,395,260, granted to Haarmann & Reimer GmbH, discloses a skin-brightening composition containing benzaldehyde oxime.

U.S. Patent 20030171617 to Bayer discloses the use of 3,4-dihydroxymandelic acid alkylamide as an antioxidant.

European patent EP2545901B1 granted to Henkel discloses a skin care formulation comprising a polymer derived from at least one acidic monomer (which is methacrylic acid) and at least one N-alkyl (meth)acrylamide monomer; and at least one sunscreen active agent, wherein the acidic monomer is present in the polymer at a weight of 5% to 35% of the total monomer content, and wherein the N-alkyl (meth)acrylamide monomer is present in the polymer at a weight of 27% to 88% of the total monomer content.

Personal care compositions that meet a range of consumer needs.

Summary of the Invention

The personal care composition according to the present invention comprises the following ingredients:

The emollient (preferably glyceryl cocoate) is present in a concentration of about 0% to about 10%, preferably from about 2% to about 6%, and more preferably from about 3% to about 6%.

The emollient wax (preferably cetyl alcohol) is present in a concentration of about 0% to about 8%, preferably from about 1% to about 4%, and more preferably from about 1.5% to about 3%.

The emulsifier (preferably cetyl phosphate) is present in an amount from about 0.2% to about 1.4%, preferably from about 0.4% to about 1.4%, and more preferably from about 0.5% to about 0.6%.

A gelling agent (preferably carbomer) comprising from about 0.4% to about 0.6%, preferably from about 0.4% to about 0.55%; and

From approximately 60% to approximately 90% water.

For clarity, and to avoid any confusion between “emollient” and “emollient wax”; “emollient wax” is referred to as “wax” in many parts of this disclosure.

These ingredients are present in the personal care composition of the present invention in the following proportions:

A) Gelling agent/emulsifier: 1 to 0.5;

B) Gelling agent/emollient: 1 to 0.02; and

C) Wax/Moisturizer: less than or equal to 0.5.

Personal care compositions may be lotions or creams. Lotions are low-viscosity topical formulations intended for application to the skin. In contrast, creams have a higher viscosity. Consumer-acceptable viscosity values range from 950 mPa to 1600 mPas (for lotions) and from 1400 mPa to 4800 mPa (for creams).

The emulsion according to the present invention may contain the following components:

Approximately 4% emollient;

Approximately 2% emollient wax;

Approximately 0.5% emulsifier; and

Approximately 0.4% gelling agent.

The cream according to the present invention may contain the following ingredients:

Approximately 6% emollient;

Approximately 3% wax;

Approximately 0.6% emulsifier; and

Approximately 0.55% gelling agent.

Attached Figure Description

Figure 1 is a graph showing the smoothness value relative to the amount of gelling agent and the amount of emulsifier.

Figure 2 is a graph showing the average discharge rate relative to the amount of gelling agent and emollient.

Detailed Implementation

Moisture can be retained in the skin by applying products that prevent water from leaving the skin. Ingredients that help form a barrier on the skin's surface include petrolatum, high concentrations of glycerin or other silicones, dimethicone, and mineral oil. Increasing the barrier also helps provide an environment where dry skin can repair itself more quickly and protects the skin from irritants or other harmful substances. Some moisturizing products contain synthetic biomimetic lipids that penetrate the stratum corneum and fill the spaces where skin lipids are lacking. These naturally derived synthetic lipids mimic skin lipids by drawing water into the skin and helping to maintain the proper balance of oil and water in the skin.

Personal care compositions for treating dry skin typically contain ingredients that compensate for dehydration by increasing the amount of water present in the stratum corneum. These compositions contain lipophilic moisturizers that inhibit moisture loss by absorbing and retaining it. Suitable lipophilic moisturizers include polyols such as glycerin or glycols, or agents that protect the skin's hydrolipidic film by preventing water evaporation through a barrier effect, including hydrocarbons such as liquid petroleum. However, the moisturizing effect provided by polyols is limited in duration, and barrier-forming agents require time to accumulate. Humectants can also be used to increase moisture in the skin. Humectants are ingredients that attract, retain, and hold moisture from the air, such as glycerin. Unfortunately, such moisturizing techniques only result in temporary relief from dry skin. More advantageous techniques are those that repair and/or enhance the skin barrier function, as these lead to a feeling of greater hydration, longer-lasting moisture retention, and are beneficial for skin health. A healthy skin barrier retains moisture and maintains a higher level of hydration.

From a scientific perspective, skin hydration is induced by epidermal differentiation stimulation and stratum corneum maturation. Keratinocytes in the basal layer, the innermost layer of the skin, proliferate and differentiate as they pass through the stratum spinosum and stratum granulosum. Through this keratinization process, keratinocytes produce natural moisturizing factors (NMF) and lipids (ceramides, cholesterol, and fatty acids) and form the stratum corneum, which contributes to a healthy skin barrier function and thus to hydrated skin, making it less susceptible to irritation and the effects of aging. Therefore, by providing the epidermis with the necessary cells and components to promote a healthy skin barrier function and associated effective moisture management, keratinocyte differentiation delivers skin hydration and resistance to skin irritation, inflammation, and/or aging. Therefore, methods for inducing keratinocyte differentiation in the epidermis will be highly desirable to counteract dehydrated, dry skin conditions, the effects of aging, and irritated, inflamed, or otherwise sensitive skin.

One approach to improving skin hydration involves controlling the skin's semi-permeability, or moisturizing capacity, by enhancing epidermal barrier function and regeneration. Skin semi-permeability plays a crucial role in skin hydration and protection. However, external damage and/or internal factors can affect this semi-permeability, leading to dry and/or sensitive skin conditions. Therefore, in addition to delivering moisture, it is essential to control potential inflammatory and irritant processes to effectively promote healthy skin barrier function, thereby resulting in healthy skin.

Clearly, the internal or endogenous mechanisms by which the skin maintains moisture revolve around optimal barrier function. The skin barrier plays a crucial role in protecting the body from moisture loss and external aggressors. Alterations in skin barrier function increase transepidermal water loss, leading to dry, flaky skin, inflammation, and damage.

A good moisturizer should (i) enhance keratinocyte differentiation to provide the skin with the necessary cells and components, thereby increasing the water content in different layers of the skin, including the entire epidermis and stratum corneum; (ii) increase water transport, aquaporins, and natural moisturizing factors, which are involved in promoting effective moisture management; and (iii) maintain optimal skin lipid balance by increasing the synthesis of new lipids. The personal care compositions of the present invention provide such functions.

definition

Naturally occurring skin lipids and sterols, as well as artificial or natural oils, humectants, emollients, lubricants, etc., can be part of commercial personal care skin moisturizing compositions.

"Emollients" are additives that have skin-softening or soothing properties. Emollients are typically complex mixtures of compounds that retain moisture in the skin after application and help to smooth the skin. Emollients increase skin hydration (water content) by reducing evaporation. A preferred emollient is glyceryl cocoate, which is a mixture of monoglycerides, diglycerides, and triglycerides derived from coconut oil.

"Emollient wax" or "wax" refers to an additive that (1) has emollient properties; (2) is oil-based; and (3) is solid at room temperature. Preferred emollient waxes are cetyl alcohol, fatty alcohol palmitate/ester (also known as hexadecyl-1-ol or palmitol). Other examples include petrolatum and silicone-derived ingredients such as cyclomethylsiloxane.

An "emulsifier" is an additive that stabilizes a mixture of two or more liquids that are normally immiscible. An example of an emulsifier is a potassium salt of a complex mixture of esters of phosphoric acid and cetyl alcohol, available from Symrise GmbH & Co. (Holzmiden, Germany).

A "gelling agent" is an additive that can form a polymeric gelling composition through crosslinking or neutralization. Gelling agents can also stabilize emulsions, form gels, increase viscosity, etc. Examples of gelling agents include polyacrylates (such as carbomer) and polysaccharides (such as cellulose). A preferred gelling agent is carbomer, a polymeric chemical composed of acrylic monomers.

Unless otherwise specified herein, all percentages (%) are by weight.

According to the present invention, ingredients in specified amounts and ratios are used to impart desired properties to a personal care composition.

Amount of ingredients

Regarding the amount of the components in the composition of the present invention, the inventors made the following observations:

Emollient (glyceryl cocoate). When using 0.1% to 2% of the emollient, the emollient effect is low. When using 2% to 6% of the emollient, good emollient properties are observed. When using 6% to 10% of the emollient, the composition exhibits an oily feel.

Wax (cetyl alcohol). When using wax from >0% to 1%, the composition exhibits low consistency (body). When using wax from 1% to 4%, the composition exhibits good consistency (body). When using wax from 4% to 8%, the composition exhibits even greater consistency (body), but may crystallize according to the aliphatic phase of the composition (see Ratio C below).

Emulsifier (potassium cetyl phosphate). When using emulsifiers from 0.2% to 0.4%, a risk of emulsion (and therefore composition) instability was observed. When using emulsifiers from 0.4% to 1.4%, the composition exhibited good emulsion stability.

Gelling agent (carbomer). When using 0.2% to 0.3% carbomer, the composition is not viscous enough and has excessive fluidity. When using 0.3% to 0.6% carbomer, the composition has an average viscosity. When using 0.6% to 1.4% carbomer, the composition is highly viscous.

Component ratio

Regarding the ratio of the components, the inventors made the following observations:

Ratio A) Gelling agent/emulsifier: 1 to 0.5 .

This ratio affects the smoothness of the composition. "Smoothness" refers to the degree to which the composition slides or causes something to slide when applied to the skin due to wetting, smoothing, or oiliness. For consumers, products with a smoothness in the range of 6-9.5 are preferred, as discussed in the examples below, especially for the texture of hydrating creams that are applied to the skin and massaged in for penetration.

It has been observed that smoothness can be controlled by the ratio and amount of gelling agent and emulsifier. Smoothness decreases with an increase in the amount of gelling agent. Smoothness increases with an increase in the amount of emulsifier. It has been found that the optimal ratio of gelling agent to emulsifier to provide the desired smoothness while allowing the components to impart their respective properties to the composition is in the range of 1 to 0.5. This surprising effect has been observed experimentally (see examples below). The inventors have determined that the effects of the two components on smoothness are different, and that the effect of the gelling agent outweighs that of the emulsifier to some extent. To maintain satisfactory smoothness, it has been found that the ratio between gelling agent and emulsifier should be in the range of 1 to 0.5.

Ratio B) Gel/Emollient: 1 to 0.02 .

This ratio affects the discharge rate of the composition. "Discharge rate" refers to the amount of product that can be recovered from its packaging (e.g., a bottle with a pump). Consumers expect products to have the highest possible discharge rate; for emulsions, a discharge rate preferably higher than 82%. For creams, the packaging differs (e.g., a jar), and consumers can use all products. It has been observed that this parameter can be controlled by gelling agents and emollients. A decrease in discharge rate is accompanied by an increase in the amount of gelling agent. A decrease in discharge rate is accompanied by an increase in the amount of emollient. It has been found that the optimal ratio for providing the desired discharge rate while also allowing the ingredients to impart their respective properties to the composition is in the range of 1 to 0.02. This surprising effect has been observed experimentally (see the examples below).

Ratio C) Wax/Moisturizer: less than or equal to 0.5 .

This ratio affects the stability of the composition. Wax is important for forming a layered structure, but it also needs to be dissolved to prevent crystallization and instability of the composition. It has been found that the appropriate amount of emollient used to dissolve the wax is at least twice the amount of wax used.

Additional ingredients

Personal care compositions may also contain additional ingredients commonly used in moisturizing compositions. For example, the composition may contain glycerin, preferably from about 5% to about 10%. The composition may also contain preservatives (phenoxyethanol; ethylhexylglycerin). The composition may also contain absorbents (corn starch). The composition may also contain one or more diluents. Suitable diluents include water.

Comparative Examples

Prepare the compositions in Tables 1, 2, and 3 as follows:

Water, disodium EDTA, and Carbopol Ultraz 10 were introduced into the main container.

Control the good dispersion of Carbopol, then heat to 80°C.

Add glycerin and control the temperature (80℃).

Add Emulsiphos 977660, Myritol 331, and Lanette 16.

Controlling the complete melting of Emulsiphos: Emulsion phase at 80°C for 15 minutes.

Neutralize to the target pH of 5.6 with an aqueous solution of sodium hydroxide and p-methoxybenzoic acid.

Begin cooling to 35°C.

When the temperature reaches 40°C, optionally add Euxyl PE9010, then add corn starch.

Check for good dispersion of purity and pH. If necessary, adjust the pH to 5.6 using NaOH.

Myritol 331 (glyceryl cocoate) is available from BASF.

Ultrez 10 (carbomer) is available from Lubrizol Advanced Materials, Inc. (Cleveland, OH).

Emulsiphos 977660 (potassium cetyl phosphate) is available from Symrise GmbH & Co.

Lanette16 (cetyl alcohol) is available from BASF.

Euxyl PE9010 (phenoxyethanol; ethylhexylglycerin) is available from Elton Chemicals S.A.

The compositions of Examples 1 to 16 were measured and observed as described below.

Table 1 - Comparative Examples 1-5

Table 2 – Comparative Examples 6-11

Table 3 – Comparative Examples 12-17

According to a working embodiment of the present invention, the compositions in Table 4 were prepared as described above. The compositions of Examples 17 to 21 were measured and observed as described below.

Table 4 – Embodiments 18-22 of the Invention

Measurement and observation

Smoothness (ratio A)

Sensory tests can be used to evaluate the creams and lotions prepared according to the present invention, as described below.

The perceived smoothness property of the composition of the present invention can be evaluated by a team of ten trained specialists. Each specialist should follow the following protocol:

1. Apply 0.07 mL to the back of your hand and spread it out with two fingers (index and middle fingers).

2. After applying two coats, assess the smoothness during the application process.

The "smoothness" of the composition during application was determined by how the product felt to a panel of specialists after two rounds of application using their fingers on the back of the hand. Each panel member noted how easily their fingers moved across the surface of the hand. The scale was from 0 to 10; 0 for non-smooth and 10 for highly smooth. Consumer-acceptable smoothness values ranged from 6.5 to 9.5.

Referring to Figure 1, the graphs in Figure 1 are based on the relationship between the average smoothness values of Comparative Examples 1 to 16 and their U10 (gelling agent) and (emulsifier) contents. For example, a smoothness of 0.2% U10 and 0.2% is the average smoothness of Comparative Examples 1, 3, 14, and 16. The vertical axis represents the smoothness values. The horizontal axis shows two types of compositions: the left side represents the composition containing 0.2% U10; and the right side represents the composition containing 1.4% U10. The dots indicate the estimated values for the composition containing 0.2% emulsifier. The square dots indicate the estimated values for the composition containing 1.4% emulsifier. The two dots on the left side of the graph represent the smoothness of the two compositions containing low gelling agent content (0.2%); the square dots represent the composition with high emulsifier content (1.4%), and the dots represent the composition with low emulsifier content (0.2%). The two dots on the right side of the graph represent the smoothness of the two compositions containing a high content of gelling agent (1.4%); the square dots represent the composition with a high content of emulsifier (1.4%), and the round dots represent the composition with a low content of emulsifier (0.2%). A straight line connects the points from the experiment with a low content of emulsifier (0.2%). A dashed line connects the points from the experiment with a high content of emulsifier (1.4%). Surprisingly, these two lines intersect, although they should be slightly parallel. The composition containing both high and low contents of gelling agent (the round dots on the right side of the graph) has surprisingly low smoothness compared to its equivalent with a high content of emulsifier. This means that, contrary to what might be expected, for compositions containing a large amount of gelling agent, the more emulsifier a composition contains, the higher its smoothness will be.

Excretion rate (ratio B)

The discharge rate should be at least approximately 82% to be acceptable to consumers. This is especially true for emulsions due to the packaging used for this type of composition (e.g., bottles equipped with pumps). The discharge rate was obtained from an automated compression test using a texture analyzer TA-XT.

The automated compression test was performed as follows: 300 pump-actuated cycles were executed using an automated system (TA-XT texture analyzer). The automated system moved the pump mechanism up and down along a 17 mm path at a speed of 10 mm/sec. The discharge rate was calculated as the change in mass of the product in a 250 mL package, expressed as a percentage, between the initial mass (before 300 cycles) and the final mass (after 300 cycles). A 100% discharge rate means that all product has been recovered from the package; a 50% discharge rate means that half of the product has been recovered.

Referring to Figure 2, Figure 2 is a graph showing the average discharge rate values of comparative Examples 1 to 16 relative to their U10 (gelling agent) and 331 (emollient) contents. For example, the discharge rate values of 0.2% U10 and 10% 331 are the average discharge rates of Examples 1, 7, 11, and 16. The vertical axis represents the discharge rate value, with 100 indicating that all product was recovered from the packaging; and by contrast, 20 indicates that only 20% of the product was recovered. The horizontal axis shows two types of compositions: the left side represents the composition containing 0.2% U10; and the right side represents the composition containing 1.4% U10. Square dots indicate estimated values for compositions containing 10% emollient (glyceryl cocoate); round dots indicate values for compositions without emollient. The two dots on the left side of the graph represent the discharge rates of the two compositions containing low amounts of gelling agent (0.2%); square dots represent compositions containing emollient (10%), and round dots represent compositions without emollient. The two points on the right side of the graph represent the discharge rates of the two compositions containing a high content of gelling agent (1.4%); the square points represent the compositions containing emollient (10%), and the round points represent the compositions without emollient. A straight line connects the points from experiments without emollient. A dashed line connects the points from experiments with 10% emollient. Surprisingly, these two lines intersect, although they should be slightly parallel. The compositions containing low contents of gelling agent and emollient (the square points on the left side of the graph) have a surprisingly high discharge rate relative to their equivalents without emollient. This means that, contrary to what might be expected, for compositions containing a small amount of gelling agent, the more emollient the composition contains, the better the discharge rate will be.

Braking and tightness

The sensory evaluation of Examples 1-17 was conducted by a specialized sensory panel according to the methods described below. The same methods can be used to evaluate the creams and lotions of the present invention in Examples 18-22.

Sensory Testing – Braking Properties During Application : Apply 0.07 mL to the back of the hand and spread it using two fingers (index and middle fingers). Measure the device speed at which the braking effect (drag) is applied while the product is spread on the skin (a total of 20 rounds of application on the back of the hand). This test will be performed by a trained panel of 10 members. The panel members should note the number of rounds applied before the braking effect (drag) is observed. The scale is from 0 to 10 (0 for very dragging and 10 for no dragging). Consumer-acceptable braking values are in the range of 1 to 5.

Sensory Testing – Tightness Attribute Scheme : Open the product in the can. Evaluate the resistance of the product when an index finger is inserted into the can. This test will be performed by a team of 10 trained specialists. The scale is from 0 to 10 (0 for non-tight (i.e., watery), 10 for very tight (i.e., gel-like)). Consumer-acceptable tightness values are in the range of 1.5 to 5.

Viscosity

Consumer-acceptable viscosity values are in the range of 950 mPa to 1600 mPas (for emulsions) and 1400 mPa to 4800 mPa (for creams). Viscosity can be measured using an Anton Paar MCR 301 rheometer according to the following procedure:

1. Set at 20℃ for 120 seconds. No shear rate.

2. Take 3 measurements every 10 seconds at a time of 5 seconds ^{- 1} second.

3. During the period from 5 ^s⁻¹ to 45 ^s⁻¹ , take 9 measurements every 4 seconds.

4. Take two measurements every 5 seconds at ^45s⁻¹ .

5. The viscosity value to be recorded is the second measurement at 45 ^s⁻¹ .

Based on the above measurement results and the evaluation by the sensory expert panel, the appearance of the personal care compositions of Embodiments 18-22 can be observed, as shown in Table 5 below:

Table 5

Claims (6)

1. A personal care composition comprising: 3 to 6% by weight of a moisturizing agent, wherein the moisturizing agent is glyceryl cocoate; 1.5 to 3% by weight of a moisturizing wax, wherein the moisturizing wax is cetyl alcohol; Emulsifier, wherein the emulsifier is cetyl phosphate; Gelling agent, wherein the gelling agent is carbomer; and water; The personal care composition contains the following ingredients in the following proportions: a) Gelling agent/emulsifier: 1 to 0.5; b) Gelling agent/emollient: 1 to 0.02; and c) Wax/Emollient: less than or equal to 0.5. 2. The personal care composition of claim 1, wherein the personal care composition comprises from 0.2% to 1.4% of an emulsifier. 3. The personal care composition of claim 1, wherein the personal care composition comprises from 0.4% to 1.4% of an emulsifier. 4. The personal care composition of claim 1, wherein the personal care composition comprises from 0.5% to 0.6% of an emulsifier. 5. The personal care composition of claim 1, wherein the personal care composition comprises from 0.4% to 0.6% of a gelling agent. 6. The personal care composition of claim 1, wherein the personal care composition comprises from 0.4% to 0.5% of a gelling agent.