JP7784820B2 - Cosmetics - Google Patents

Description

The present invention relates to cosmetics.

Alpha hydroxy acids (AHAs) are known to promote epidermal turnover (metabolism) and shrink pores, but when effective amounts of these alpha hydroxy acids are incorporated into cosmetics, the pH of the base decreases and the salt concentration increases. This makes it difficult to create formulations with the required viscosity, as the (electrostatic repulsion) thickeners used in typical gel and cream bases tend to lose viscosity over time. As a result, salt and acid resistance are required, which can limit the applications and formulations available.

To date, cosmetics containing specific polyether-modified silicones as emulsifiers that have excellent emulsion stability and a pleasant feel when used are known (see Patent Document 1), but no cosmetics containing alpha-hydroxy acids are known that are favorable in terms of viscosity (hardness) over time and the associated feel when used.

International Publication No. 2019/230578

The inventors surprisingly discovered that by creating a cosmetic containing specific amounts of alpha-hydroxy acid, specific polyether-modified silicone, and amino acid salt, it is possible to create a cosmetic that is easy to use and does not lose hardness over time. The present invention is based on these findings.

According to the present invention, the following inventions are provided.
(1) (A) an α-hydroxy acid,
A cosmetic comprising (B) a polyether-modified silicone having a viscosity of 10,000 mm ² /s or more at 25°C, and (C) an amino acid salt, wherein the blending amount of (A) α-hydroxy acid is 1.5 to 10 mass% based on the total amount of the cosmetic.
(2) The cosmetic preparation according to (1), wherein the α-hydroxy acid (A) is at least one selected from the group consisting of glycolic acid, lactic acid, and citric acid.
(3) The cosmetic according to (1) or (2), wherein the amino acid salt (C) is one or more selected from the group consisting of sodium L-glutamate and pyrrolidone carboxylic acid salts.
(4) The cosmetic preparation according to any one of (1) to (3), further comprising (D) a silicone elastomer.
(5) The cosmetic according to (4), wherein the blending amount of (D) silicone elastomer is 0.3 to 5% by mass relative to the total amount of the cosmetic.
(6) The cosmetic preparation according to any one of (1) to (5), further comprising (E) powder.
(7) The cosmetic preparation according to (6), wherein the (E) powder is titanium oxide or amodimethicone-treated silica.
(8) The cosmetic according to any one of (1) to (7), which is a water-in-oil emulsion cosmetic.
(9) The cosmetic preparation according to any one of (1) to (8), which is a cream.

The use of the cosmetic of the present invention is advantageous in that it provides a cosmetic that is easy to use and whose hardness does not decrease over time.

Specific Description of the Invention

The present invention provides
(A) an α-hydroxy acid,
The present invention provides a cosmetic comprising (B) a polyether-modified silicone having a viscosity of 10,000 mm ² /s or more at 25°C, and (C) an amino acid salt, wherein the blending amount of the α-hydroxy acid (A) is 1.5 to 10 mass % relative to the total amount of the cosmetic.

<(A) α-Hydroxy Acid>
The α-hydroxy acids used in the cosmetic preparation of the present invention have conventionally been used as buffers or neutralizing agents in cosmetics and cleansers, and are also incorporated into various cosmetic preparations for the purposes of softening keratin, activating cells, etc. The α-hydroxy acids incorporated into the cosmetic preparation of the present invention are not particularly limited, but examples include glycolic acid, lactic acid, malic acid, tartaric acid, citric acid, glyceric acid, pyruvic acid, mandelic acid, etc., and may be incorporated alone or in combination of two or more. Of these, one or more selected from the group consisting of glycolic acid, lactic acid, and citric acid are preferred, and a combination of glycolic acid, lactic acid, and citric acid is more preferred.

The amount of alpha-hydroxy acid used in the cosmetic of the present invention is 1.5 to 10% by mass, and preferably 3 to 5% by mass, based on the total amount of the cosmetic.

When the α-hydroxy acid used in the cosmetic of the present invention includes glycolic acid, the amount of glycolic acid blended is not particularly limited, but is preferably 1 to 8% by mass, and more preferably 2 to 5% by mass, of the total amount of the cosmetic.

When the α-hydroxy acid used in the cosmetic of the present invention includes lactic acid, the amount of lactic acid blended is not particularly limited, but is preferably 0.5 to 3% by mass, and more preferably 1 to 2% by mass, of the total amount of the cosmetic.

When the α-hydroxy acid used in the cosmetic of the present invention includes citric acid, the amount of citric acid blended is not particularly limited, but is preferably 1 to 4 mass% of the total amount of the cosmetic, and more preferably 1.2 to 3 mass% of the total amount of the cosmetic.

<(B) Polyether-modified silicone>
The polyether-modified silicone contained in the cosmetic of the present invention is a polyether-modified silicone having a viscosity of 10,000 mm ² /s or more at 25° C., preferably 15,000 mm ² /s or more, and more preferably 20,000 mm ² /s or more. By adjusting the viscosity of the polyether-modified silicone at 25° C. to 10,000 mm ² /s or more, good emulsion stability can be ensured. Among these, those that do not have alkyl chains in the side chains and have polyoxyalkylene groups in the side chains of a linear or branched silicone skeleton are preferred.

Specific examples of polyether-modified silicones include PEG/PPG-19/19 dimethicone (trade name "BY11-030", HLB=3, viscosity 30,000 mm ² /s; manufactured by Dow Corning Toray Co., Ltd.).

The HLB value of the polyether-modified silicone contained in the cosmetic of the present invention is not particularly limited, but is preferably 8.0 or less, and more preferably 4 or less.

The amount of polyether-modified silicone contained in the cosmetic of the present invention is not particularly limited, but is preferably 0.1 to 10% by mass relative to the total amount of the cosmetic, and more preferably 0.5 to 2% by mass relative to the total amount of the cosmetic.

<(C) Amino Acid Salt>
The amino acid salt contained in the cosmetic of the present invention is not particularly limited, but specific examples thereof include aspartate, glutamate, cysteine salt, histidine salt, lysine salt, ornithine salt, tryptophan salt, pyrrolidone carboxylate, arginine-glutamate, ornithine-glutamate, lysine-glutamate, lysine-aspartate, and ornithine-aspartate, and more specific examples thereof include sodium aspartate, potassium aspartate, and aspartic acid salt. Examples of the amino acid salt include magnesium glutamate, calcium aspartate, sodium glutamate, potassium glutamate, magnesium glutamate, calcium glutamate, glutamic acid hydrochloride, cysteine hydrochloride, histidine hydrochloride, lysine hydrochloride, ornithine hydrochloride, ornithine acetate, tryptophan hydrochloride, pyrrolidone carboxylate, arginine-glutamate, ornithine-glutamate, lysine-glutamate, lysine-aspartate, ornithine-aspartate, etc. According to a preferred embodiment of the present invention, the amino acid salt contained in the cosmetic of the present invention is one or more selected from the group consisting of L-glutamate (e.g., sodium L-glutamate) and pyrrolidone carboxylate (e.g., sodium pyrrolidone carboxylate), more preferably sodium L-glutamate or sodium pyrrolidone carboxylate.

The amount of amino acid salt contained in the cosmetic of the present invention is not particularly limited, but is preferably 0.5 to 2% by mass relative to the total amount of the cosmetic, and more preferably 0.8 to 1.5% by mass relative to the total amount of the cosmetic.

<Silicone elastomer>
The cosmetic of the present invention preferably further comprises a silicone elastomer. The silicone elastomer is not particularly limited, but preferably includes one or more selected from the group consisting of dimethicone crosspolymer, dimethicone/vinyl dimethicone crosspolymer, dimethicone/phenylvinyl dimethicone crosspolymer, vinyl dimethicone/lauryl dimethicone crosspolymer, lauryl polydimethylsiloxyethyl dimethicone/bis-vinyl dimethicone crosspolymer, alkyl (C30-45) cetearyl dimethicone crosspolymer, and cetearyl dimethicone crosspolymer, and particularly preferably includes dimethicone crosspolymer, dimethicone/vinyl dimethicone crosspolymer, or dimethicone/phenylvinyl dimethicone crosspolymer.

It is preferable to blend the silicone elastomer in the form of a swollen product swollen with a liquid oil at room temperature (25°C). This further improves the dispersibility and stability of the silicone elastomer. Examples of liquid oils used for swelling include liquid silicone oil, liquid hydrocarbon oil, liquid ester oil, and liquid higher fatty acid. In particular, liquid oils with a low viscosity at room temperature, for example, 100 mPa·s or less, are preferred. The preferred viscosity range is 1 to 100 mPa·s. The preferred mixing ratio of silicone elastomer to liquid oil is 5:95 to 40:60 by mass.

As the liquid oil-swollen silicone elastomer, commercially available products can also be used, and examples of commercially available products include the following:
Examples of swollen dimethicone crosspolymers include 9040 silicone elastomer blend, 9041 silicone elastomer blend, 9045 silicone elastomer blend, and EL-8040ID silicone organic blend (all manufactured by Dow Corning Toray Co., Ltd.).

The amount of silicone elastomer contained in the cosmetic of the present invention is not particularly limited, but is preferably 0.3 to 5% by mass relative to the total amount of the cosmetic, and more preferably 0.5 to 2% by mass relative to the total amount of the cosmetic.

<(E) Powder>
The cosmetic of the present invention preferably further contains a powder. Examples of the powder include talc, mica, kaolin, mica, sericite, muscovite, phlogopite, synthetic mica, lepidolite, biotite, lepidolite, vermiculite, magnesium carbonate, calcium carbonate, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, strontium silicate, metal tungstate, magnesium, (spherical) silica, zeolite, barium sulfate, calcined calcium sulfate (calcined gypsum), calcium phosphate, fluorapatite, hydroxyapatite, and the like. Inorganic powders such as quartz, ceramic powder, metal soaps (zinc myristate, calcium palmitate, aluminum stearate, etc.), and boron nitride; spherical organic powders such as polyamide spherical resin powder (nylon spherical powder), spherical polyethylene, cross-linked polymethyl (meth)acrylate spherical resin powder, spherical polyester, cross-linked polystyrene spherical resin powder, styrene-acrylic acid copolymer spherical resin powder, benzoguanamine spherical resin powder, polytetrafluoroethylene spherical powder, and spherical cellulose; titanium oxide inorganic white pigments such as titanium dioxide and zinc oxide; inorganic red pigments such as iron oxide (red iron oxide) and iron titanate; inorganic brown pigments such as γ-iron oxide; inorganic yellow pigments such as yellow iron oxide and ochre; inorganic black pigments such as black iron oxide, carbon black and low-order titanium oxide; inorganic purple pigments such as mango violet and cobalt violet; inorganic green pigments such as chromium oxide, chromium hydroxide and cobalt titanate; inorganic blue pigments such as ultramarine and iron blue; titanium oxide-coated mica, titanium oxide-coated bismuth oxychloride, Examples of suitable pigments include pearl pigments such as titanium oxide-coated talc, colored titanium oxide-coated mica, bismuth oxychloride, borosilicate (Ca/Al), and fish scale foil; metal powder pigments such as aluminum powder and copper powder; color materials such as red, yellow, orange, yellow, green, and blue, or color materials (organic pigments) obtained by lake-forming these with zirconium, barium, aluminum, or the like; and natural pigments such as chlorophyll and β-caroline. Of these, titanium oxide or amodimethicone-treated silica is particularly preferred.

The powder that may be included in the cosmetic composition of the present invention may be surface-treated or not, and its shape is not particularly limited, but silica surface-treated with amodimethicone or the like is preferred. There are no particular limitations on the average particle size of the powder, but powders with a particle size of approximately 1 to 100 μm are typically preferred.

<Other ingredients>
In addition to the above-mentioned components, the cosmetic of the present invention may contain other components commonly used in cosmetics, such as ultraviolet protection agents, various aqueous solvents, thickeners, sequestering agents, sugars, amino acids, organic amines, pH adjusters, stabilizers, skin nutrients, antioxidants, antioxidant aids, fragrances, etc., as needed, within the scope of not impairing the effects of the present invention.

The cosmetic of the present invention is preferably a water-in-oil emulsion cosmetic, more preferably a gel or cream, and particularly preferably a cream.

The present invention will be specifically described based on the following examples, but the present invention is not limited to these examples. Contents are expressed in mass % unless otherwise specified.

Test Example 1
The cosmetics of Examples 1 to 5 and Comparative Examples 1 to 5 below (see Tables 1 and 2) were evaluated for "pore contraction effect," as well as for usability, including "lightness and freshness of spread,""smooth and smooth feeling on skin after application," and "pore blurring." Furthermore, the hardness (measured with an 11.3φ or 8φ diameter) and emulsion particle size of these cosmetics were measured, and the hardness stability was subsequently evaluated (after 4 weeks). The evaluation methods and evaluation criteria for each evaluation were as follows. The evaluation results are also shown in Tables 3 and 4 below.

(1) Pore Shrinkage and Improvement Effect Each sample was applied to the face of 10 expert panelists, and a sensory evaluation was conducted on the pore shrinkage and improvement effect after 4 weeks of application.
<Evaluation criteria>
A: 7 to 10 people answered that it has a firming and wrinkle-improving effect.
B: 4 to 6 people answered that it had a firming and wrinkle-improving effect.
C: Three or fewer people answered that it had a firming and wrinkle-improving effect.

(2) Evaluation of usability in terms of lightness of spread and freshness Each sample was applied to the face of 10 expert panelists, and a sensory evaluation of usability was carried out.
<Evaluation criteria>
A: 7 to 10 people answered that it spreads easily and has a refreshing feel.
B: 4 to 6 people answered that it spreads easily and has a refreshing feel when used.
C: Three or fewer people answered that it spreads easily and has a refreshing feel when used.

(3) Evaluation of Usability in Terms of Smooth and Smooth Feeling on Skin After Use Each sample was applied to the face of 10 expert panelists, and a sensory evaluation of usability was carried out.
<Evaluation criteria>
A: All 10 people answered that the product left their skin feeling smooth and silky after use.
B: 7 to 9 people answered that the skin felt smooth and silky after use.
C: 4 to 6 people answered that the skin felt smooth and silky after use.
D: 3 or less people answered that the skin felt smooth and silky after use.

(4) Evaluation of Pore Blurring Effect Each sample was applied to the face of 10 expert panelists, and a sensory evaluation of usability was carried out.
<Evaluation criteria>
A: All 10 people answered that it blurred their pores.
B: 7 to 9 people answered that it blurred their pores.
C: 4 to 6 people answered that it blurred pores.
D: Three or fewer people answered that it blurred pores.

(5) Hardness (initial)
The hardness of each cosmetic material was measured in an atmosphere of 25°C using a rheometer (manufactured by Sun Scientific Co., Ltd.: COMPAC-100II; measured with 11.3φ or 8φ, needle penetration 10.0 mm).

(6) Emulsified particle size Immediately after emulsification (initial stage), each cosmetic was observed under a microscope (Hirox Digital Microscope RH-2000. Lens used: MXB-5000REZ: High-Range: x1000) and the average particle size of the emulsified particles was measured five times. Here, the particle size is the particle size observed under a transmission electron microscope, and the average particle size is a value expressed as a circle-equivalent diameter, and is shown as the range of the five measurement results.

(7) Hardness Stability The stability of each cosmetic was evaluated based on the following evaluation criteria.
<Evaluation criteria>
A: The condition of the cosmetic after 4 weeks is the same as when the cosmetic was prepared (initial state).
B: After 4 weeks, the state of the cosmetic was such that the hardness had decreased from that at the time of preparation (initial stage) or the emulsion particles were large, but this was within the acceptable range for a cosmetic.
C: After 4 weeks, the state of the cosmetic was such that the hardness had decreased from that at the time of preparation (initial stage) of the cosmetic, or the emulsion particles had become larger, which was outside the acceptable range for a cosmetic.

Claims (7)

(A) an α-hydroxy acid,
A cosmetic comprising (B) a polyether-modified silicone having a viscosity of 10,000 mm ² /s or more at 25°C, and (C) an amino acid salt, wherein the blending amount of the α-hydroxy acid (A) is 1.5 to 10 mass% based on the total amount of the cosmetic;
the amino acid salt (C) is at least one selected from the group consisting of sodium L-glutamate and pyrrolidone carboxylic acid salts,
(D) further comprising a silicone elastomer;
the blending amount of the (B) polyether-modified silicone is 0.1 to 10% by mass relative to the total amount of the cosmetic;
A cosmetic in which the blending amount of the amino acid salt (C) is 0.5 to 2% by mass relative to the total amount of the cosmetic . The cosmetic preparation according to claim 1, wherein the (A) alpha-hydroxy acid is one or more selected from the group consisting of glycolic acid, lactic acid, and citric acid. The cosmetic according to claim 1 or 2, wherein the blending amount of the silicone elastomer (D) is 0.3 to 5% by mass relative to the total amount of the cosmetic. The cosmetic preparation according to any one of claims 1 to 3, further comprising (E) powder. The cosmetic preparation according to claim 4, wherein the (E) powder is titanium oxide or amodimethicone-treated silica. The cosmetic preparation according to any one of claims 1 to 5, which is a water-in-oil emulsion cosmetic preparation. The cosmetic preparation according to any one of claims 1 to 6 is a cream.