Cosmetics

Abstract

To provide two-layer cosmetics that excel in usability, cleaning ability, and separability.SOLUTION: Two-layer cosmetics contain (A) a specific amount of alkyl glyceryl ether, (B) a specific amount of ampholytic surfactant, (C) a specific amount of metal metaphosphate, (D) alcohol and / or benzoate excluding (A), (E) water, and (F) oil.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a cosmetic preparation, and more particularly to a cosmetic preparation that separates into two layers when left standing but is easily emulsified by shaking. [Background technology]

[0002] Conventionally, two-layer cosmetics have been known that separate into two layers when left standing, but are emulsified by shaking before application. Such cosmetics generally contain an aqueous phase composed of aqueous components and an oil phase composed of oily components. When such two-layer cosmetics are applied to the skin after shaking, they are characterized by the ability to simultaneously obtain the feel and efficacy of both the aqueous and oily components. For example, the aqueous component can provide the efficacy of water-soluble chemicals and a refreshing feel, while the oil component can provide the efficacy of oil-soluble chemicals and cleansing effects. More specifically, by making a cleanser into a two-layer cleanser, the oil component can enhance the removal performance of water-insoluble substances, while the aqueous component can provide a refreshing feel. This allows for a cleanser that has high cleansing power, even capable of easily removing waterproof makeup, while leaving little stickiness after use.

[0003] However, two-layer cosmetic compositions need to be able to separate cleanly into two layers when left standing. This is because insufficient separation leaves a bad impression as a product and can cause visual preconceptions that indicate whether sufficient performance or efficacy is being achieved. However, the inventors' studies have found that when additives with preservative properties, such as polyhydric alcohols, sodium benzoate, or isopropyl alcohol, are combined to enhance the preservative properties of two-layer cosmetic compositions, the compositions may not separate cleanly. For this reason, there is a demand for two-layer cosmetic compositions that exhibit excellent separation properties even when such ingredients are combined. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2019-089750 Summary of the Invention

[0005] From this perspective, the present inventors conducted research and found that a specific material is effective in improving the separation properties of a two-layer cosmetic composition containing a preservative. That is, the present invention is based on this finding, and the problem to be solved by the present invention is to provide a cosmetic composition that has an excellent feel when used and cleansing ability, has visually satisfying separation properties, and is easily emulsifiable so that it quickly emulsifies upon shaking.

[0006] According to the present invention, the following inventions are provided. [1] A two-layer cosmetic composition, (A) 0.01% by mass to 0.3% by mass of an alkyl glyceryl ether based on the total mass of the two-layer cosmetic; (B) 0.005% by mass to 0.4% by mass of an amphoteric surfactant based on the total mass of the two-layer cosmetic; (C) 0.005% by mass to 0.5% by mass of a metal metaphosphate salt based on the total mass of the two-layer cosmetic; (D) an alcohol and / or benzoate other than (A); (E) water, (F) Oil A two-layer cosmetic comprising: [2] The cosmetic according to [1], wherein the proportion of the aqueous phase is 40 to 80 mass % based on the total mass of the two-layer cosmetic. [3] The cosmetic composition according to [1] or [2], wherein the alkyl glyceryl ether is selected from the group consisting of ethylhexylglycerin, hexylglycerin, and cyclohexylglycerin. [4] The cosmetic preparation according to any one of [1] to [3], wherein the alcohol is selected from the group consisting of dipropylene glycol, hexylene glycol, isopentyl diol, butanediol, propanediol, diglycerin, glycerin, n-propyl alcohol, dipropylene alcohol, and isopropyl alcohol. [5] The cosmetic preparation according to any one of [1] to [4], wherein the metal benzoate is sodium benzoate and the metal metaphosphate is sodium metaphosphate. [6] The cosmetic preparation according to any one of [1] to [5], wherein the oil is selected from the group consisting of hydrocarbon oils, alcohol esters, and silicone oils. [7] The cosmetic according to any one of [1] to [6], wherein the content of the alkyl glyceryl ether is 0.15 to 0.25% by mass based on the total mass of the two-layer cosmetic. [8] The cosmetic according to any one of [1] to [7], wherein the content of the amphoteric surfactant is 0.03 to 0.3 mass % based on the total mass of the two-layer cosmetic. [9] The cosmetic according to any one of [1] to [8], wherein the content of the metal metaphosphate is 0.05 to 0.4 mass % based on the total mass of the two-layer cosmetic.

[10] The cosmetic preparation according to any one of [1] to [9], which is a cleansing agent.

[0007] The cosmetic composition according to the present invention has excellent usability and cleansing ability, and also has visually pleasing separation properties and the ease of emulsification, allowing for rapid emulsification upon shaking. Furthermore, the cosmetic composition according to the present invention uses environmentally friendly materials and does not require materials that produce unpleasant odors during use. Specific Description of the Invention

[0008] [Two-layer cosmetics] The two-layer cosmetic composition according to the present invention comprises: (A) an alkyl glyceryl ether; (B) an amphoteric surfactant; (C) a metal metaphosphate; (D) an alcohol and / or benzoate other than (A); (E) water, (F) Oil These components constitute an aqueous phase and an oil phase depending on the water-solubility or oil-solubility of each component. The ratio of the aqueous phase to the oil phase is adjusted depending on the purpose, but in order to fully obtain the effects of the water-soluble components and the oil-soluble components, the ratio of the aqueous phase is preferably 40 to 80 mass%, and more preferably 50 to 70 mass%, based on the total mass of the two-layer cosmetic.

[0009] The components contained in the two-layer cosmetic composition according to the present invention are described below.

[0010] (A) Alkyl glyceryl ether The cosmetic according to the present invention contains an alkyl glyceryl ether. This alkyl glyceryl ether is believed to be present primarily in the oil phase of a two-layer cosmetic and contribute to improving separation. The alkyl glyceryl ether has a structure in which an alkyl group is ether-bonded to a hydroxyl group of glycerin. While any of monoalkyl glyceryl ether, dialkyl glyceryl ether, and trialkyl glyceryl ether can be used, monoalkyl glyceryl ether is preferred because it has an excellent effect of improving separation. Furthermore, the number of carbon atoms in the alkyl group is preferably 4 to 10, more preferably 6 to 8. The alkyl group may have a linear, branched, or cyclic structure. More specifically, the alkyl glyceryl ether is preferably selected from the group consisting of ethylhexylglycerin, hexylglycerin, and cyclohexylglycerin.

[0011] The content of the alkyl glyceryl ether is preferably 0.01 to 0.3% by mass, and more preferably 0.15 to 0.25% by mass, based on the total mass of the two-layer cosmetic.

[0012] (B) Amphoteric surfactant The cosmetic composition according to the present invention contains an amphoteric surfactant. It is believed that this amphoteric surfactant contributes to the separation of the aqueous and oily layers in the two-layer cosmetic composition according to the present invention. While there are no particular limitations on the amphoteric surfactants that can be used, preferred examples include imidazoline-based amphoteric surfactants and betaine-based amphoteric surfactants. Specific examples include lauryl betaine, cocamidopropyl betaine, lauryl dimethylaminoacetic acid betaine, amidobetaine, sulfobetaine, sodium cocoamphoacetate, 2-undecyl-N,N,N-(hydroxyethylcarboxymethyl)-2-imidazoline sodium, and 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt. Two or more of these amphoteric surfactants can be used in combination.

[0013] The content of the amphoteric surfactant is preferably 0.005 to 0.4% by mass, and more preferably 0.03 to 0.3% by mass, based on the total mass of the two-layer cosmetic.

[0014] (C) Metal metaphosphate The cosmetic composition according to the present invention contains a metal metaphosphate. It is believed that this metal metaphosphate, in combination with an amphoteric surfactant, contributes to the separation properties of the two-layer cosmetic composition. Metaphosphate is a compound represented by the general formula (HPO3) n (where n is a number representing the degree of polymerization), and is primarily a polyphosphate structure in which PO4 units are linked together, or a cyclophosphate structure in which PO3 units form a cyclic structure. In the present invention, the metaphosphate metal salt may have either of these structures, or may be a mixture thereof. The metal ions constituting the metal salt are not particularly limited, but are preferably highly water-soluble, and are more preferably alkali metal salts or alkaline earth metal salts. Typically, sodium metaphosphate or potassium metaphosphate is used, with sodium metaphosphate being most preferred.

[0015] The content of the metal metaphosphate is preferably 0.015 to 0.5% by mass, and more preferably 0.05 to 0.4% by mass, based on the total mass of the two-layer cosmetic.

[0016] (D) Alcohols and / or benzoates The cosmetic preparation according to the present invention contains an alcohol and / or a benzoate. Here, the alkyl glyceryl ether (component (A)) has an alcoholic hydroxyl group, but in the present invention, it is not included in the alcohol (component (D)).

[0017] The alcohol may be a monohydric alcohol or a polyhydric alcohol, and may be a lower alcohol or a higher alcohol.

[0018] In the present invention, a polyhydric alcohol refers to a compound having two or more hydroxyl groups bonded to a hydrocarbon chain. The hydrocarbon chain may contain an ether bond. This polyhydric alcohol is believed to provide preservative properties to the cosmetic composition of the present invention, and is preferably incorporated into the aqueous phase.

[0019] Examples of such polyhydric alcohols include: dihydric alcohols (e.g., ethylene glycol, propylene glycol, hexylene glycol, isopentyl diol, propanediol, butanediol, trimethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, tetramethylene glycol, 2,3-butylene glycol, pentamethylene glycol, 2-butene-1,4-diol, and octylene glycol); Trihydric alcohols (e.g., glycerin, trimethylolpropane, etc.); tetrahydric alcohols (e.g., pentaerythritol, 1,2,6-hexanetriol, etc.); Pentahydric alcohols (e.g., xylitol, etc.); Hexahydric alcohols (e.g., sorbitol, mannitol, etc.); Polyhydric alcohol polymers (e.g., diethylene glycol, dipropylene glycol, triethylene glycol, polypropylene glycol, tetraethylene glycol, diglycerin, polyethylene glycol, triglycerin, tetraglycerin, polyglycerin, and the like); etc.

[0020] Of these, the polyhydric alcohol is preferably selected from the group consisting of dipropylene glycol, hexylene glycol, isopentyl diol, butanediol, propanediol, diglycerin, and glycerin.

[0021] When a polyhydric alcohol is used, the content is, for example, 11 to 19% by mass, and preferably 11 to 16% by mass, based on the total mass of the two-layer cosmetic.

[0022] In the present invention, a monohydric alcohol refers to a hydrocarbon chain with one hydroxyl group bonded thereto. This monohydric alcohol is believed to be able to impart antiseptic properties to the cosmetic composition of the present invention, and is preferably incorporated into the oil phase. Specific examples of the monohydric alcohol include isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, phenoxy alcohol, and ethyl alcohol, with isopropyl alcohol and n-propyl alcohol being preferred.

[0023] When a monohydric alcohol is used, the content is preferably 0.2 to 0.7% by mass, and more preferably 0.25 to 0.55% by mass, based on the total mass of the two-layer cosmetic.

[0024] These alcohols can be selected arbitrarily depending on the purpose, but it is preferable to use alcohols other than phenoxy alcohol and ethanol in order to reduce the burden on the skin.

[0025] In the present invention, the metal benzoate is a salt in which the hydrogen of benzoic acid is substituted with any metal. It is believed that the metal benzoate provides preservative properties mainly to the aqueous phase in the cosmetic composition according to the present invention. For this reason, it is preferable that the metal benzoate is highly water-soluble, and it is more preferable that it is an alkali metal salt or an alkaline earth metal salt. Typically, sodium benzoate or potassium benzoate is used, and sodium benzoate is most preferred.

[0026] When a metal benzoate is used, the content is preferably 0.1 to 0.5% by mass, and more preferably 0.1 to 0.4% by mass, based on the total mass of the two-layer cosmetic.

[0027] (D)Water The two-layer cosmetic according to the present invention further contains water as a component of the aqueous phase. As the water, water generally used in cosmetics can be used, such as purified water, ion-exchanged water, tap water, etc. (E) Oil The cosmetic according to the present invention contains an oil. The oil is the main component constituting the oil phase of the two-layer cosmetic, dissolving oil-soluble components that impart various effects to the cosmetic and imparting cleansing capabilities to the cosmetic. The oil to be incorporated into the cosmetic of the present invention can be selected from those typically used in cosmetics and is not particularly limited. Examples include hydrocarbon oils, alcohol esters, silicone oils, higher fatty acids, and higher alcohols. In the present invention, it is preferable to use an oil selected from the group consisting of hydrocarbon oils, alcohol esters, and silicone oils.

[0028] Examples of hydrocarbon oils include mineral oil (liquid paraffin), hydrogenated polyisobutene, isododecane, isohexadecane, squalane, ceresin, microcrystalline wax, etc. Among these, hydrocarbon oils selected from the group consisting of mineral oil (liquid paraffin), hydrogenated polyisobutene, isododecane, isohexadecane, and squalane are preferred.

[0029] Examples of alcohol esters include cetyl ethylhexanoate, (cetyl octanoate), ethylhexyl palmitate, isopropyl myristate, octyldodecyl myristate, butyl stearate, decyl oleate, neopentyl glycol dicaprate, ethylene glycol dioctanoate, diisostearyl malate, trimethylolpropane trioctanoate, trimethylolpropane triisostearate, pentaolithritol tetraoctanoate, glycerin trioctanoate, glycerin triisostearate, ethyl acetate, butyl acetate, amyl acetate, etc. Among these, alcohol esters selected from the group consisting of cetyl ethylhexanoate, ethylhexyl palmitate, isopropyl myristate, and neopentyl glycol dicaprate are preferred.

[0030] Examples of silicone oils include methylphenylsilicone and dimethicone, which have a siloxane structure in the main chain and are substituted with methyl or phenyl groups, and other modified polysiloxanes, such as amino-modified polysiloxanes, polyether-modified polysiloxanes, alkyl-modified polysiloxanes, and fluorine-modified polysiloxanes. Of these, methylphenylsilicone and methylpolysiloxane are preferred, and specifically, diphenyldimethicone, dodecamethylpentasiloxane, or decamethyltetrasiloxane are preferably used.

[0031] Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, undecylenic acid, tall acid, isostearic acid, linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).

[0032] Examples of higher alcohols include straight-chain alcohols (e.g., lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, cetostearyl alcohol, etc.), branched-chain alcohols (e.g., lanolin alcohol, cholesterol, phytosterol, hexyldodecanol, isostearyl alcohol, octyldodecanol, etc.), and the like.

[0033] These oils can be used in combination of two or more. Preferably, the oil is liquid at room temperature. Oils that are solid at room temperature can also be used as long as they become liquid when mixed with other oils.

[0034] The cosmetic preparation according to the present invention may contain other ingredients commonly used in cosmetics, other than those mentioned above, to the extent that the effects of the present invention are not impaired. Examples of these ingredients include thickeners, moisturizers, water-soluble drugs (e.g., arbutin, ascorbic acid glucoside, tranexamic acid, 4-methoxysalicylate, etc.), UV absorbers, chelating agents, pH adjusters, preservatives, pigments, dyes, surfactants, powder components, etc.

[0035] The cosmetic composition according to the present invention has an excellent appearance, in which the aqueous and oily layers clearly separate when left standing, and each layer forms a clear, transparent layer without any cloudiness. The cosmetic composition separated into two layers can be easily emulsified uniformly by shaking it by hand while still in the container, and can be used. After emulsification, the aqueous and oily layers clearly separate again when left standing for a short period of time, for example, 6 hours or less.

[0036] This two-layer cosmetic is not simply separated into two layers, but rather exhibits the combined performance of the advantages of both the aqueous and oily phases when used. Specifically, by blending appropriate agents into the aqueous or oily phase, it can be used as a lotion or cleanser. As a cleanser, the two-layer cosmetic of the present invention can exert the cleansing effect of the oily phase while simultaneously providing a refreshing feeling in use due to the aqueous phase.

[0037] [Cosmetic manufacturing method] The cosmetic preparation according to the present invention can be produced by blending and mixing the various components. The order of blending is not particularly limited, but it is common to prepare an aqueous phase and an oily phase separately and then seal them in a single container. That is, the cosmetic preparation can be produced by preparing an aqueous phase and an oily phase separately and then blending the aqueous phase and the oily phase together. [Example]

[0038] The present invention will be described in detail based on the following examples, but the present invention is not limited to these examples. Contents are expressed in mass % unless otherwise specified.

[0039] [Examples 1 to 14 and Comparative Examples 1 to 6] Cleansing agents were prepared by blending the ingredients according to the formulation shown in Table 1, and their performance was evaluated. Each evaluation item was evaluated using the following methods.

[0040] 2 layer formation The cosmetic was vigorously shaken and then allowed to stand, and the state of separation was observed and evaluated according to the following criteria. A: The mixture separated into two layers cleanly within 12 hours. B: After 12 hours or more, the mixture separated into two layers. C: No separation into two layers

[0041] Refreshing After the cosmetic preparation had penetrated and become uniform, it was applied to the skin and evaluated according to the following criteria depending on the feeling when used. A: Very refreshing B: Refreshing C: Not refreshing enough

[0042] [Table 1-1]

[0043] [Table 1-2]

[0044] [Examples 15 to 32] Cleansing agents were prepared by blending the components according to the formulation shown in Table 2, and their performance was evaluated in the same manner as in Example 1.

[0045] [Table 2-1]

[0046] [Table 2-2]

Claims

1. A two-layer cosmetic, (A) 0.01% by mass to 0.3% by mass of an alkyl glyceryl ether based on the total mass of the two-layer cosmetic; (B) 0.005% by mass to 0.4% by mass of an amphoteric surfactant based on the total mass of the two-layer cosmetic; (C) 0.005% by mass to 0.5% by mass of a metal metaphosphate salt, based on the total mass of the two-layer cosmetic; (D) an alcohol other than (A) and / or a metal salt of benzoic acid; (E) water; (F) Oil A two-layer cosmetic comprising:

2. 2. The cosmetic according to claim 1, wherein the proportion of the aqueous phase is 40 to 80% by mass based on the total mass of the two-layer cosmetic.

3. 3. The cosmetic preparation according to claim 1, wherein the alkyl glyceryl ether is selected from the group consisting of ethylhexylglycerin, hexylglycerin, and cyclohexylglycerin.

4. The cosmetic preparation according to any one of claims 1 to 3, wherein the alcohol is selected from the group consisting of dipropylene glycol, hexylene glycol, isopentyl diol, butanediol, propanediol, diglycerin, glycerin, n-propyl alcohol, dipropylene alcohol, and isopropyl alcohol.

5. The cosmetic preparation according to any one of claims 1 to 4, wherein the metal benzoate is sodium benzoate and the metal metaphosphate is sodium metaphosphate.

6. The cosmetic preparation according to any one of claims 1 to 5, wherein the oil is selected from the group consisting of hydrocarbon oils, alcohol esters, and silicone oils.

7. 7. The cosmetic according to claim 1, wherein the content of the alkyl glyceryl ether is 0.15 to 0.25% by mass based on the total mass of the two-layer cosmetic.

8. The cosmetic according to any one of claims 1 to 7, wherein the content of the amphoteric surfactant is 0.03 to 0.3% by mass based on the total mass of the two-layer cosmetic.

9. 9. The cosmetic according to claim 1, wherein the content of the metal metaphosphate is 0.05 to 0.4% by mass based on the total mass of the two-layer cosmetic.

10. The cosmetic preparation according to any one of claims 1 to 9, which is a cleanser.

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