Skin cosmetic

Abstract

To provide a skin cosmetic that offers a fresh feeling upon application, has a moisturizing effect, suppresses post-application stickiness, and ensures favorable affinity with wet skin.SOLUTION: The present invention provides a skin cosmetic comprising: (A) 0.05-3 mass% of an acrylic acid-based thickener; (B) 0.01-0.5 mass% of a polysaccharide thickener; (C) 1-30 mass% of an oil agent that is liquid at 25°C; and (D) 0.001-5 mass% of at least one selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a skin cosmetic. [Background technology]

[0002] Water-soluble vitamins and amino acids are known to enhance the moisturizing effect of the skin, and are incorporated into many cosmetics, including water-based cosmetics. Water-based cosmetics have a fresh and refreshing feel when used, but the presence of water-soluble vitamins and amino acids can lead to stickiness, and the stickiness can be felt especially in the summer. In addition, cosmetics with a fresh feel when used sometimes do not provide sufficient moisturizing effect.

[0003] For example, Patent Document 1 proposes a cosmetic composition that contains trimethylglycine, an amino acid derivative, in combination with pectin, a monosaccharide, xanthan gum, and a carboxyvinyl polymer as an aqueous cosmetic composition that has a moisturizing effect and is not sticky. Patent Document 2 proposes a liquid cosmetic composition that contains an electrolyte beauty ingredient such as an amino acid in combination with a phospholipid and a dilauroyl glutamic acid lysine salt. Patent Document 3 proposes a transparent cosmetic preparation that contains ascorbic acid, a type of vitamin, or a derivative thereof in combination with an oligomer ester, a polyalkylene glycol, a polyhydric alcohol, a monohydric alcohol, and a polysaccharide. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-080139 A [Patent Document 2] International Publication No. 2009 / 020067 [Patent Document 3] JP 2017-081879 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the cosmetic preparation disclosed in Patent Document 1 has problems in that it is insufficiently moisturizing when applied, and also in that it does not blend well with wet skin, such as when sweating. The liquid cosmetic composition disclosed in Patent Document 2 does not blend well with the skin, not only on wet skin but also on dry skin. The transparent cosmetic preparation disclosed in Patent Document 3 has excellent compatibility with dry skin, but does not sufficiently blend with wet skin, and also does not provide an adequate feeling of freshness when applied. Vitamins and amino acids are likely to be effective when they penetrate the skin. Therefore, when the skin is wet, such as when sweating, the cosmetics do not blend well with the skin as described in Patent Documents 1 to 3, and this causes a problem that the moisturizing effect of the vitamins and amino acids is weakened.

[0006] The present invention has been made in consideration of the above problems, and aims to provide a skin cosmetic which has a fresh feeling when applied, has a moisturizing effect, is less sticky after application, and has good skin affinity when applied to wet skin. [Means for solving the problem]

[0007] As a result of intensive research, the inventors have found that a skin cosmetic preparation that can solve the above-mentioned problems can be obtained by combining in specified amounts an acrylic acid-based thickener, a thickening polysaccharide, an oil that is liquid at 25°C, and one or more selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof, and have thus completed the present invention.

[0008] The present invention includes the following aspect [1]. [1] A skin cosmetic preparation comprising 0.05 to 3 mass% of the following component (A), 0.01 to 0.5 mass% of the following component (B), 1 to 30 mass% of the following component (C), and 0.001 to 5 mass% of the following component (D). (A) Acrylic acid-based thickener (B) Thickening polysaccharides (C) Oil that is liquid at 25℃ (D) one or more selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof Effect of the Invention

[0009] The skin cosmetic of the present invention has a fresh feel when applied, has a moisturizing effect, is less sticky after application, and blends well with wet skin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described, however, the present invention is not limited to the embodiment described in this specification, and various modifications are possible without departing from the gist of the present invention. In this specification, a numerical range defined using the symbol "~" is intended to include both the upper and lower limits of the range. For example, "2~5" means 2 or more and 5 or less. Furthermore, in any numerical range described in this specification, the upper or lower limit of the numerical range can be replaced with a value shown in an example or a value that is uniquely derived from an example.

[0011] The skin cosmetic preparation of the present invention contains (A) 0.05 to 3 mass% of an acrylic acid-based thickener, (B) 0.01 to 0.5 mass% of a thickening polysaccharide, (C) 1 to 30 mass% of an oil agent that is liquid at 25°C, and (D) 0.001 to 5 mass% of one or more members selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof, and may further contain other ingredients within a range that does not impair the object of the present invention. Conventional cosmetics tend to blend poorly with wet skin compared to dry skin, and are particularly prone to poor skin compatibility when the moisture on the skin contains salt, such as when sweaty. In contrast, the skin cosmetic of the present invention contains the above-mentioned components (A), (B), (C) and (D) in the amounts within the above-mentioned ranges, so that it blends well with the skin even on wet, salty skin, and furthermore, it provides a fresh feeling when applied, has excellent moisturizing effects, and suppresses stickiness after application. In the present invention, the term "freshness upon application" means a state in which the product is moisturized upon application and does not feel sticky. In the present invention, the term "skin compatibility" means a feeling of penetration into the skin, and the faster the penetration into the skin is felt, the better the skin compatibility. Each component contained in the skin cosmetic of the present invention will be described below.

[0012] [Component (A)] The component (A) used in the present invention is an acrylic acid-based thickener. The acrylic acid-based thickener is an acrylic acid-based polymer that exhibits high viscosity and gelling function when dissolved in water, and specifically includes a homopolymer of (meth)acrylic acid, (meth)acrylate, or (meth)acrylamide, or a copolymer obtained by copolymerizing at least one selected from the group consisting of (meth)acrylic acid, (meth)acrylate, and (meth)acrylamide. As the acrylic acid-based thickener, any acrylic acid-based thickener that has been conventionally used in skin cosmetics or external skin preparations can be appropriately selected and used.

[0013] The acrylic acid-based thickener may be, for example, a graft polymer obtained by graft-polymerizing acrylic acid onto a sugar polymer. Here, the sugar polymer is a polymer having a glucoside structure such as cellulose or starch, and starch is preferred from the viewpoint of skin compatibility. The graft polymer may be a salt. The type of salt is not particularly limited, but is preferably an alkali metal salt such as lithium salt, sodium salt, or potassium salt, and is particularly preferably a sodium salt. As the graft polymer, for example, a starch-sodium acrylate graft polymer is preferably used. As the starch-sodium acrylate graft polymer, specifically, commercially available products such as Saranjur ST-100SP, Saranjur ST-100MC, and Saranjur 300 (manufactured by Sanyo Chemical Industries, Ltd.) can be used.

[0014] The acrylic acid thickener may be crosslinked polyacrylic acid. The polyacrylic acid may be a salt. The type of salt is not particularly limited, but is preferably an alkali metal salt such as lithium salt, sodium salt, or potassium salt, and is particularly preferably a sodium salt, i.e., sodium polyacrylate. As the crosslinked polyacrylic acid, for example, a carboxyvinyl polymer is preferably used. The carboxyvinyl polymer is a polymer having acrylic acid as a main monomer, and may be a homopolymer, copolymer, or interpolymer, but is preferably a homopolymer. Specific examples of carboxyvinyl polymers that can be used include commercially available products such as Carbopol (registered trademark) 940, Carbopol (registered trademark) 941, Carbopol (registered trademark) 980, and Carbopol (registered trademark) 981 (manufactured by Lubrizol Advanced Materials); Sinteren (manufactured by Wako Pure Chemical Industries, Ltd.); and AQUPEC HV-501E (manufactured by Sumitomo Seika Chemicals Co., Ltd.).

[0015] The acrylic acid-based thickener may also include a (meth)acrylic acid-alkyl (meth)acrylate copolymer. The (meth)acrylic acid-alkyl (meth)acrylate copolymer is a copolymer of at least one selected from acrylic acid and methacrylic acid and at least one selected from alkyl acrylate and alkyl methacrylate. The (meth)acrylic acid-alkyl (meth)acrylate copolymer may be copolymerized with a small amount of other monomers within a range that does not impair the effect as an acrylic acid-based thickener. The copolymerization ratio of the other monomers is appropriately adjusted according to the type of the monomer, and is not particularly limited, but may be, for example, 30% by mass or less, 10% by mass or less, or 1% by mass or less. As the (meth)acrylic acid-alkyl (meth)acrylate copolymer, an acrylic acid-alkyl methacrylate copolymer is preferable from the viewpoint of improving skin compatibility on wet skin. The acrylic acid-alkyl methacrylate copolymer may be an alkyl-modified carboxyvinyl polymer. The alkyl-modified carboxyvinyl polymer is a polymer in which a part or all of the carboxyl groups of the above-mentioned carboxyvinyl polymer are esterified with alkyl groups. Moreover, the alkyl group contained in the (meth)acrylic acid-alkyl (meth)acrylate copolymer is preferably an alkyl group having 10 to 30 carbon atoms, from the viewpoint of improving skin compatibility on wet skin. Specific examples of the acrylic acid-alkyl methacrylate copolymer (alkyl-modified carboxyvinyl polymer) that can be used include commercially available products such as Carbopol (registered trademark) Ultrez 20 polymer, Carbopol (registered trademark) 1382, and Pemulen (registered trademark) TR-1 (manufactured by Lubrizol Advanced Materials).

[0016] The acrylic acid thickener further includes hydroxyethyl acrylate-sodium acryloyldimethyl taurate copolymer, polyacrylamide, sodium acrylate-sodium acryloyldimethyl taurate copolymer, and acrylamide-sodium acryloyldimethyl taurate copolymer. As the hydroxyethyl acrylate-sodium acryloyldimethyl taurate copolymer, specifically, commercially available products such as SIMULGEL NS (manufactured by SEPPIC) can be used. As the sodium acrylate-sodium acryloyldimethyl taurate copolymer, specifically, commercially available products such as SIMULGEL EG or SIMULGEL EPG (manufactured by SEPPIC) can be used.

[0017] In the skin cosmetic of the present invention, the acrylic acid-based thickener is preferably at least one selected from starch-sodium acrylate graft polymer and acrylic acid-alkyl methacrylate copolymer (alkyl-modified carboxyvinyl polymer), since this tends to improve skin compatibility on wet skin, particularly when the skin is sweaty and the moisture on the skin contains salt, and starch-sodium acrylate graft polymer is particularly preferred, since it provides a fresh feeling upon application, has a moisturizing effect, is non-sticky after application, and has excellent skin compatibility on wet skin.

[0018] The component (A) may be used either as a single type alone or as a suitable combination of two or more types. In the skin cosmetic of the present invention, the content of component (A) is 0.05 to 3 mass% of the total amount of the skin cosmetic. If the content of component (A) is less than the above lower limit, a fresh feeling of use upon application is not obtained, skin compatibility on wet skin is insufficient, and the stability of the skin cosmetic may be deteriorated. In the present invention, the stability of a skin cosmetic means the property of the cosmetic being less likely to cause a decrease in viscosity and separation. If the content of component (A) is more than the above upper limit, stickiness occurs after application, skin compatibility on wet skin is poor, and the fresh feeling upon application is also reduced. The content of component (A) in the total amount of the skin cosmetic is preferably 0.1% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.2% by mass or more, from the viewpoints of improving the fresh feeling upon application and the compatibility with wet skin, and is preferably 2.5% by mass or less, more preferably 2% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.5% by mass or less, from the viewpoints of suppressing stickiness after application and improving the compatibility with wet skin.

[0019] [Component (B)] The component (B) used in the present invention is a thickening polysaccharide. The thickening polysaccharide is a polysaccharide that exhibits high viscosity and has a gelling function when dissolved in water. As the thickening polysaccharide, a thickening polysaccharide that has been conventionally used in skin cosmetics or skin external preparations can be appropriately selected and used. Examples of the thickening polysaccharides include gum arabic, guar gum, quince seed gum, quince, agar, xanthan gum, pullulan, gellan gum, pectin, etc. Among these, from the viewpoint of improving the compatibility of the skin cosmetic preparation of the present invention with wet skin, at least one selected from xanthan gum and gellan gum is preferred, and gellan gum is particularly preferred.

[0020] The component (B) may be used alone or in appropriate combination of two or more kinds. In the skin cosmetic of the present invention, the content of component (B) is 0.01 to 0.5% by mass based on the total amount of the skin cosmetic. If the content of component (B) is less than the lower limit, the freshness upon application is insufficient, and the moisturizing effect and skin compatibility on wet skin are also insufficient. If the content of component (B) is more than the upper limit, the freshness upon application is insufficient, and the skin compatibility on wet skin is also poor. The content of component (B) in the total amount of the skin cosmetic is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, from the viewpoints of improving the moisturizing effect, the freshness upon application, and the skin compatibility on wet skin, and is preferably 0.3% by mass or less, more preferably 0.2% by mass or less, from the viewpoints of improving the freshness upon application and the skin compatibility on wet skin.

[0021] In the skin cosmetic of the present invention, the mass ratio (A / B) of component (A) to component (B) is not particularly limited, but from the viewpoint of improving the freshness upon application and the compatibility with wet skin, it is preferably 0.5 or more, more preferably 0.8 or more, and from the viewpoint of improving the freshness upon application and the compatibility with wet skin, and from the viewpoint of suppressing stickiness after application, it is preferably 20 or less, more preferably 10 or less, even more preferably 6 or less, still more preferably 5.5 or less, and particularly preferably 3 or less.

[0022] [Component (C)] The component (C) used in the present invention is an oil that is liquid at 25°C. As the oil, liquid oils conventionally used in skin cosmetics or skin external preparations can be appropriately selected and used. The component (C) may be at least one selected from polar oils and non-polar oils. Here, the polar oil is an oil that contains a polar group such as a hydroxyl group, a carboxyl group, an ether bond or an ester bond in the molecule, and the non-polar oil is an oil that does not contain a polar group. As component (C), a single oil that is liquid at 25°C may be used alone, or two or more may be used in appropriate combination. From the viewpoint of improving the stability of the skin cosmetic composition of the present invention and its compatibility with wet skin, however, it is preferable for the composition to contain at least a polar oil, and it is even more preferable for the composition to contain a combination of a polar oil and a non-polar oil.

[0023] Examples of the polar oil include fatty acids, ester oils, and triglycerides. Examples of the fatty acids include oleic acid and isostearic acid. Examples of the ester oil include cetyl 2-ethylhexanoate, isopropyl myristate, and 2-ethylhexyl palmitate. Examples of the triglycerides include triglycerides of higher fatty acids having 6 or more carbon atoms, such as caproic acid, caprylic acid, capric acid, 2-ethylhexanoic acid, isotridecanoic acid, isopalmitic acid, isostearic acid, eicosanoic acid, and oleic acid, and vegetable oils and fats such as olive oil, sunflower oil, safflower oil, castor oil, and camellia oil. The polar oil is preferably at least one selected from ester oils and vegetable oils and fats, more preferably contains at least ester oil, and even more preferably contains a combination of ester oil and vegetable oil. As the ester oil, 2-ethylhexanoate is particularly preferable, and as the vegetable oil, olive oil is particularly preferable.

[0024] Examples of the non-polar oil include hydrocarbon oils and silicone oils that do not contain polar groups. Examples of the hydrocarbon oil include liquid paraffin, liquid isoparaffin, and squalane. Examples of the silicone oils that do not contain polar groups include decamethylcyclopentasiloxane, methylpolysiloxane, dimethylpolysiloxane, and polymethylcyclosiloxane. From the viewpoint of suppressing stickiness after application, the non-polar oil is preferably at least one selected from hydrocarbon oils and silicone oils that do not contain polar groups, and more preferably hydrocarbon oils. As the hydrocarbon oil, squalane is particularly preferred, and as the silicone oil that does not contain polar groups, methylpolysiloxane is particularly preferred.

[0025] In the skin cosmetic of the present invention, the content of component (C) is 1 to 30% by mass based on the total amount of the skin cosmetic. If the content of component (C) is less than the above lower limit, the moisturizing effect and skin compatibility on wet skin are insufficient. If the content of component (C) is more than the above upper limit, stickiness occurs after application and freshness at the time of application is not obtained. The content of component (C) in the total amount of the skin cosmetic is preferably 2% by mass or more, more preferably 5% by mass or more, from the viewpoint of improving the moisturizing effect and skin compatibility on wet skin, and is preferably 25% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and even more preferably 10% by mass or less, from the viewpoint of suppressing stickiness after application and improving freshness at the time of application.

[0026] Furthermore, when component (C) contains a combination of polar oil and non-polar oil, the content of the polar oil, when the total amount of the polar oil and non-polar oil is 100 parts by mass, is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, even more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more, in order to improve compatibility with wet skin, and is preferably 95 parts by mass or less, more preferably 90 parts by mass or less, in order to suppress stickiness after application.

[0027] [Component (D)] The component (D) used in the present invention is at least one selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof. The skin cosmetic of the present invention is usually an aqueous skin cosmetic containing water as a base. The "water-soluble" component (D) may be dissolved in the water in the skin cosmetic of the present invention, and preferably has a solubility of 50 g / L or more in water at 20°C. The vitamin derivatives and amino acid derivatives usable as component (D) are also water-soluble. The "derivative" in component (D) is a compound obtained by changing a part of the structure of the original compound to an extent that the properties are not significantly changed. Examples of derivatives of water-soluble vitamins include compounds obtained by changing water-soluble vitamins by phosphorylation, esterification, or a combination thereof. Examples of derivatives of water-soluble amino acids include compounds obtained by replacing the hydrogen atom of the amino group of a water-soluble amino acid with a substituent such as an alkyl group. From the viewpoint of moisturizing effect, the alkyl group is preferably an alkyl group having 1 to 3 carbon atoms, and a methyl group is particularly preferable.

[0028] The water-soluble vitamins and derivatives thereof can be appropriately selected from water-soluble vitamins and derivatives thereof conventionally used in aqueous skin cosmetics or skin external preparations, and are not particularly limited. Examples of water-soluble vitamins include vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacinamide), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine), vitamin B7 (biotin), vitamin B9 (folic acid), vitamin B12 (cyanocobalamin, hydroxocobalamin, methylcobalamin), vitamin C (ascorbic acid), etc. Examples of the derivatives of water-soluble vitamins include derivatives of the various water-soluble vitamins mentioned above, such as riboflavin phosphate (vitamin B2 derivative), nicotinic acid adenine dinucleotide phosphate (vitamin B3 derivative), pyridoxine cyclic phosphate (vitamin B6 derivative), L-ascorbic acid 2-glucoside (vitamin C derivative), sodium ascorbyl phosphate (vitamin C derivative), 3-O-ethyl ascorbic acid (vitamin C derivative), etc. Among the above water-soluble vitamins and their derivatives, at least one selected from niacinamide and L-ascorbic acid 2-glucoside is preferred from the viewpoint of improving the moisturizing effect.

[0029] The water-soluble amino acid and its derivative can be appropriately selected from water-soluble amino acids and their derivatives conventionally used in aqueous skin cosmetics or skin external preparations, and is not particularly limited. Examples of water-soluble amino acids include essential amino acids such as valine, histidine, and lysine; non-essential amino acids such as alanine, arginine, cysteine, glutamine, glutamic acid, glycine, proline, and serine. Examples of water-soluble amino acid derivatives include compounds in which the hydrogen atom of the amino group of the above-mentioned various water-soluble amino acids is replaced with an alkyl group, and specifically, trimethylglycine and the like can be mentioned. Among them, the water-soluble amino acid and its derivative are preferably at least one selected from alanine, arginine, serine, and proline, more preferably at least alanine, and even more preferably alanine, serine, and proline in combination, from the viewpoint of improving moisturizing effect.

[0030] The component (D) may be used alone or in appropriate combination of two or more kinds. In the skin cosmetic of the present invention, the content of component (D) is 0.001 to 5% by mass based on the total amount of the skin cosmetic. If the content of component (D) is less than the above lower limit, sufficient moisturizing effect cannot be obtained. If the content of component (D) is more than the above upper limit, stickiness occurs after application. If the content of water-soluble amino acid or its derivative is too high, the moisture upon application is likely to be impaired. The content of component (D) in the total amount of the skin cosmetic is preferably 0.003% by mass or more, more preferably 0.005% by mass or more, from the viewpoint of improving the moisturizing effect, and is preferably 4% by mass or less, more preferably 3% by mass or less, from the viewpoint of suppressing stickiness after application and improving the moisture upon application. Furthermore, when the skin cosmetic contains a water-soluble vitamin or a derivative thereof as component (D), the content of the water-soluble vitamin or a derivative thereof in the total amount of the skin cosmetic is preferably 1 to 5 mass%, more preferably 2 to 5 mass%, in order to achieve a well-balanced and excellent moisturizing effect and an effect of suppressing stickiness after application. When a water-soluble amino acid or a derivative thereof is contained as component (D), the content of the water-soluble amino acid and its derivative in the total amount of the skin cosmetic is preferably 0.001 to 2 mass%, more preferably 0.005 to 1 mass%, and even more preferably 0.005 to 0.01 mass%, from the viewpoint of achieving a well-balanced and excellent moisturizing effect, fresh feeling upon application, and effect of suppressing stickiness after application.

[0031] The total content of the above-mentioned components (A), (B), (C) and (D) relative to the total amount of the skin cosmetic of the present invention is preferably 1% by mass or more, and more preferably 5% by mass or more, in order to easily exert the effects of the present invention. On the other hand, in order to contain sufficient water to improve the freshness of the skin cosmetic of the present invention when applied, and in order to contain sufficient amounts of other components described below, the total content of the above-mentioned components (A), (B), (C) and (D) relative to the total amount of the skin cosmetic of the present invention is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0032] 〔water〕 The skin cosmetic of the present invention generally contains water as a base in addition to the above components (A) to (D). As the water contained in the skin cosmetic of the present invention, it is preferable to use water from which impurities have been removed, which is generally used in skin cosmetics or topical skin preparations, etc., and for example, ion-exchanged water, purified water, etc. are preferably used. In the skin cosmetic of the present invention, the water content is usually 50 to 99% by mass, preferably 55 to 90% by mass, and more preferably 60 to 85% by mass, based on the total amount of the skin cosmetic. When the water content is equal to or greater than the lower limit, the effect of improving the fresh feeling of use due to the combination of the above-mentioned components (A) to (D) is easily obtained. When the water content is equal to or less than the upper limit, the moisturizing effect, suppression of stickiness, and improvement of skin compatibility according to the present invention are easily obtained.

[0033] [Other ingredients] The skin cosmetic of the present invention may further contain, as necessary, other ingredients that are commonly used in skin cosmetics or topical skin preparations, etc., in addition to the above-mentioned components (A) to (D) and water, within the scope of the object of the present invention. Examples of the other components include surfactants, moisturizers such as polyhydric alcohols, sequestering agents, dyes, preservatives, fragrances, pH adjusters, solubilizers, lipophilic emulsifiers, and physiologically active components required depending on the application. In the skin cosmetic of the present invention, the content of the above-mentioned other ingredients is not particularly limited and may be, for example, 1% by mass or more, or 5% by mass or more, relative to the total amount of the skin cosmetic. However, in order to facilitate the exertion of the effects of the present invention, the content is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0034] The method for producing the skin cosmetic of the present invention is not particularly limited. For example, the skin cosmetic of the present invention can be produced by mixing the above-mentioned components (A) to (D) and the other components added as necessary, and then adjusting the amount of water so that each component has the desired content.

[0035] The skin cosmetic of the present invention is suitably provided, for example, in the form of a liquid or gel, that is, a gel having a high water content. Furthermore, the skin cosmetic of the present invention is preferably provided specifically as a lotion, a gel-like lotion, an emulsion, a gel-like emulsion, a beauty essence, a gel-like beauty essence, an all-in-one gel, a lotion spray, a gel spray, or the like. EXAMPLES

[0036] Hereinafter, the embodiment of the present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited to these examples. Note that parts and % are by weight unless otherwise specified.

[0037] [Examples 1 to 12 and Comparative Examples 1 to 8: Preparation of Skin Cosmetics] First, components (B) to (D) shown in Table 1 or Table 2 and other components shown in Table 3 were dissolved in the appropriate aqueous or oily phase, and then the aqueous and oily phases were mixed to obtain a mixed solution. Next, a dispersion in which component (A) shown in Table 1 or Table 2 was dispersed in a polyhydric alcohol was added to the above mixed solution and mixed to obtain a mixture containing components (A) to (D). Water was further added as necessary to the obtained mixture so that each component had a content (mass%) shown in Table 1 or Table 2, thereby preparing the skin cosmetics of Examples 1 to 12 and Comparative Examples 1 to 8. As component (A), the following compound was used. Starch-sodium acrylate graft polymer: Saranjur ST-100SP (manufactured by Sanyo Chemical Industries, Ltd.) Acrylic acid-alkyl methacrylate copolymer: Carbopol® Ultrez 20 polymer (Lubrizol Advanced Materials)

[0038] [Evaluation of Skin Cosmetics] The skin cosmetics obtained in each Example and Comparative Example were evaluated as follows. The evaluation results are shown in Tables 1 and 2. Note that in the evaluation results shown in Tables 1 and 2, the numbers in parentheses are the total evaluation points of the 20 panelists.

[0039] (1) Freshness when applied Twenty panelists (women aged 23 to 55) scored the freshness felt when applying and spreading the skin cosmetic on the face according to the following evaluation criteria. <Evaluation criteria> 2 points: It clearly felt fresh. 1 point: Felt slightly moist. 0 points: Did not feel fresh. Based on the total score of the 20 panelists, the freshness of the skin cosmetics when applied was evaluated as follows: A skin cosmetic with a total score of 20 points or more was judged to have a freshness when applied. ◎: Total score is 30 or more ○: Total score is 20 or more and less than 30 points △: Total score is 10 or more but less than 20 points ×: Total score is less than 10 points

[0040] (2) Moisturizing effect Twenty panelists (women aged 23-55) measured the moisture content of the stratum corneum on the inside of the forearm before and after application of the skin cosmetic product, following the procedure below. First, the panelists waited for 15 minutes in a room at around 20°C, after which the moisture content of the inside of the forearm was measured before application of the skin cosmetic product, and this value was designated as the "initial value." After that, the moisture content of the inside of the forearm was measured 2 hours after spreading approximately 0.2 g of the skin cosmetic product on the skin, and this value was designated as the "moisture content value after 2 hours." A stratum corneum moisture measuring device (product name "Skicon-200EX", manufactured by IBS Co., Ltd.) was used to measure the moisture content of the stratum corneum. The ratio of the "moisture content value after 2 hours" to the "initial value" was calculated and scored according to the following evaluation criteria. <Evaluation criteria> 2 points: The moisture content after 2 hours was more than twice the initial value. 1 point: Moisture content after 2 hours was more than 1x but less than 2x the initial value. 0 points: The moisture content after 2 hours was less than 1 times the initial value. The moisturizing effect of the skin cosmetics was evaluated as follows based on the total score of the 20 panelists. A skin cosmetic with a total score of 20 points or more was determined to have a moisturizing effect. ◎: Total score is 30 or more ○: Total score is 20 or more and less than 30 points △: Total score is 10 or more but less than 20 points ×: Total score is less than 10 points

[0041] (3) No stickiness after application Twenty panelists (women aged 23 to 55) assessed the lack of stickiness of the skin cosmetics after spreading them on their faces and gave scores according to the following evaluation criteria. <Evaluation criteria> 2 points: Did not feel sticky. 1 point: Slightly sticky feeling. 0 points: The product clearly felt sticky. Based on the total score of the 20 panelists, the skin cosmetic preparations were evaluated for non-stickiness after application as follows: A total score of 20 points or more was determined to be a skin cosmetic preparation that suppressed stickiness after application. ◎: Total score is 30 or more ○: Total score is 20 or more and less than 30 points △: Total score is 10 or more but less than 20 points ×: Total score is less than 10 points

[0042] (4) Good compatibility with wet skin Twenty panelists (women aged 23-55) were asked to rate how well the skin cosmetics blended with the skin when applied to wet skin, using the following evaluation criteria. The panelists were asked to stay in a room with a temperature of 30°C and humidity of 60% for 30 minutes and spread the skin cosmetics on their sweaty faces. <Evaluation criteria> 2 points: I felt that it blended clearly well with my skin. 1 point: I felt that it blended slightly well with my skin. 0 points: I felt that it did not blend well with my skin. Based on the total score of the 20 panelists, the skin cosmetic was evaluated for its compatibility with wet skin as follows: A skin cosmetic with a total score of 20 points or more was determined to have good compatibility with wet skin. ◎: Total score is 30 or more ○: Total score is 20 or more and less than 30 points △: Total score is 10 or more but less than 20 points ×: Total score is less than 10 points

[0043] [Table 1]

[0044] [Table 2]

[0045] [Table 3]

[0046] The skin cosmetics prepared in Examples 1 to 12 were skin cosmetics of the present invention containing 0.05 to 3 mass% of the above-mentioned component (A), 0.01 to 0.5 mass% of component (B), 1 to 30 mass% of component (C), and 0.001 to 5 mass% of component (D), and had a refreshing feel when applied, had a moisturizing effect, was less sticky after application, and was a skin cosmetic that blended well with wet skin. On the other hand, the skin cosmetics prepared in Comparative Examples 1 to 8 did not provide sufficient effects in terms of fresh feeling upon application, moisturizing effect, suppression of stickiness after application, or skin compatibility on wet skin. That is, since the skin cosmetic preparation of Comparative Example 1 did not contain component (A), it lacked freshness when applied and did not blend well with wet skin. The skin cosmetic preparation of Comparative Example 2 contained too much component (A), so it was very sticky after application, did not blend well with wet skin, and had insufficient freshness upon application. The skin cosmetic preparation of Comparative Example 3 did not contain component (B), and therefore had no fresh feeling upon application, and the moisturizing effect and skin compatibility on wet skin were insufficient. The skin cosmetic preparation of Comparative Example 4 contained a large amount of component (B), and therefore did not blend well with wet skin, and the freshness felt upon application was insufficient. The skin cosmetic preparation of Comparative Example 5 contained a large amount of component (C), and therefore was very sticky after application and had insufficient freshness upon application. The skin cosmetic of Comparative Example 6 did not contain component (C), and therefore had insufficient moisturizing effect and was also insufficient in compatibility with wet skin. The skin cosmetic preparation of Comparative Example 7 contained a large amount of component (D), and therefore was very sticky after application and had insufficient freshness upon application. The skin cosmetic preparation of Comparative Example 8 did not contain component (D) and therefore had insufficient moisturizing effect.

[0047] [Formulation example] Table 4 shows formulation examples of emulsions, which are skin cosmetics of the present invention.

[0048] [Table 4]

[0049] Table 5 shows formulation examples of all-in-one gels, which are skin cosmetics of the present invention.

[0050] [Table 5] [Industrial Applicability]

[0051] The skin cosmetic of the present invention can be used by applying it to the skin, and since it exhibits unique effects that cannot be obtained with conventional aqueous skin cosmetic preparations, specifically, a fresh feeling upon application, a moisturizing effect, a lack of stickiness after application, and good compatibility with wet skin, it is expected to be used as a skin cosmetic for a variety of purposes.

Claims

[Claim 1] A skin cosmetic comprising 0.05 to 3 mass% of the following component (A), 0.01 to 0.5 mass% of the following component (B), 1 to 30 mass% of the following component (C), and 0.001 to 5 mass% of the following component (D). (A) Acrylic acid-based thickener (B) Thickening polysaccharides (C) An oil that is liquid at 25°C (D) one or more selected from the group consisting of water-soluble vitamins, water-soluble amino acids, and derivatives thereof

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