W / o / w type emulsified composition

Abstract

Disclosed is a W / O / W type emulsified composition exhibiting excellent stability. This W / O / W type emulsified composition comprises: an inner water phase; an oil phase in which the inner water phase is dispersed; and an outer water phase in which the oil phase is dispersed. The inner water phase contains an osmotic pressure regulator. The osmotic pressure regulator generates the osmotic pressure between the inner water phase and the outer water phase. Contained as a surfactant for emulsifying the inner aqueous phase in the oil phase is at least one selected from the group consisting of polyethylene glycol dipolyhydroxystearate and polyglycerol fatty acid esters having an average degree of polymerization of glycerol of 2-9. The osmotic pressure regulator contains at least one selected from the group consisting of citric acid, citrates, and sulfates.

Description

W / O / W type emulsion composition REFERENCE TO RELATED APPLICATIONS

[0001] This patent application claims priority to an earlier filed Japanese patent application, Patent Application No. 2023-223483 (filing date: December 28, 2023), the entire disclosure of which is incorporated herein by reference.

[0002] The present invention relates to a W / O / W emulsion composition.

[0003] Conventionally, O / W and W / O types have been widely used as emulsion cosmetics, but W / O / W emulsion cosmetics, which are multi-type emulsions, can impart a sensation of use that is not possible with either O / W or W / O emulsion cosmetics; for example, cosmetics that have a refreshing sensation of use, such as a phase inversion upon application to the skin, are known.

[0004] For example, the W / O / W emulsion composition disclosed in Patent Document 1 has a small amount of internal aqueous phase during production, and after preparing the W / O / W emulsion composition, water is transferred from the external aqueous phase to the internal aqueous phase due to the difference in osmotic pressure. As a result, a high internal phase (oil phase + internal aqueous phase) ratio can be obtained with a relatively small amount of oil phase, and a fresh feeling can be achieved despite the high viscosity, and a unique phase inversion sensation can be achieved due to the release of the internal aqueous phase upon application to the skin.

[0005] Furthermore, by adding a drug or the like to the inner aqueous phase of a W / O / W emulsion composition, the drug can be coated with the oil phase and the outer aqueous phase, thereby improving its stability, such as its oxidation resistance.

[0006] On the other hand, it is more difficult to form an emulsion form for a W / O / W emulsion composition than for an O / W emulsion composition or a W / O emulsion composition, and even if a W / O / W emulsion is produced, the emulsion stability decreases over time or with changes in temperature.

[0007] In order to solve these problems, it is desirable to develop a W / O / W emulsion composition that exhibits high stability over time and against temperature changes.

[0008] Japanese Patent Application Laid-Open No. 2002-275029

[0009] The present inventors have found that W / O / W emulsion compositions containing specific osmolality adjusting agents exhibit good stability, particularly at high temperatures. The present invention is based on this finding.

[0010] Thus, the present invention provides a W / O / W emulsion composition that exhibits good stability.

[0011] The present invention provides the following: (1) A W / O / W emulsion composition comprising an internal aqueous phase, an oil phase in which the internal aqueous phase is dispersed, and an external aqueous phase in which the oil phase is dispersed, wherein the internal aqueous phase contains an osmotic pressure adjuster that generates osmotic pressure between the internal aqueous phase and the external aqueous phase, and wherein the surfactant that emulsifies the internal aqueous phase in the oil phase is one or more selected from the group consisting of polyglycerol fatty acid esters of glycerin having an average degree of polymerization of 2 to 9 and polyethylene glycol dipolyhydroxystearate, and the osmotic pressure adjuster contains at least one selected from the group consisting of citric acid, citrate salts, and sulfates. (2) The composition according to (1), wherein the amount of the osmotic pressure adjuster in the composition is 0.01 to 0.5% by weight. (3) The composition according to (1) or (2), wherein the surfactant that emulsifies the internal aqueous phase in the oil phase comprises one or more polyglycerol fatty acid esters selected from the group consisting of polyglyceryl oleate, polyglyceryl isostearate, polyglyceryl diisostearate, polyglyceryl dipolyhydroxystearate, and polyglyceryl polyricinoleate, each having an average degree of glycerol polymerization of 2 to 9. (4) The composition according to (3), wherein the surfactant that emulsifies the internal aqueous phase in the oil phase contains at least one OH group in the main chain of the fatty acid residue. (5) The composition according to any one of (1) to (3), wherein the surfactant for emulsifying the internal aqueous phase in the oil phase is one or more polyglycerol fatty acid esters selected from the group consisting of polyglyceryl-4 oleate, polyglyceryl-6 oleate, polyglyceryl-2 isostearate, polyglyceryl-6 polyricinoleate, polyglyceryl-2 diisostearate, and polyglyceryl-2 dipolyhydroxystearate. (6) The composition according to any one of (1) to (5), wherein the surfactant for emulsifying the internal aqueous phase in the oil phase is polyglyceryl-6 polyricinoleate. (7) The composition according to any one of (1) to (6), wherein the oil phase contains one or more oils selected from the group consisting of polar oils having an IOB value of 0.1 to 0.8.(8) The composition according to (7), wherein the oil is one or more selected from the group consisting of castor oil, bisdiglyceryl polyacyladipate-2, and dipentaerythritol hexahydroxystearate. (9) The composition according to (7) or (8), wherein the amount of the oil is 3 to 20% by weight of the composition. (10) The composition according to any one of (1) to (9), wherein the external aqueous phase contains a thickener having an alkyl group. (11) The composition according to (10), wherein the thickener having an alkyl group is one or more selected from the group consisting of alkyl-modified carboxyvinyl polymer, ammonium acryloyldimethyltaurate / beheneth-25 methacrylate crosspolymer, and acrylates / steareth-20 methacrylate copolymer. (12) The composition according to any one of (1) to (11), wherein the composition is a cosmetic composition.

[0012] According to the present invention, there is provided a W / O / W emulsion composition that exhibits good stability. Specific Description of the Invention

[0013] According to one aspect of the present invention, there is provided a W / O / W emulsion composition comprising an internal aqueous phase, an oil phase in which the internal aqueous phase is dispersed, and an external aqueous phase in which the oil phase is dispersed. The internal aqueous phase in this composition contains an osmotic pressure adjuster. This osmotic pressure adjuster includes at least one selected from the group consisting of citric acid, citrates, and sulfates, and generates osmotic pressure between the internal aqueous phase and the external aqueous phase, thereby transferring water from the external aqueous phase to the internal aqueous phase. This allows a high internal phase (oil phase + internal aqueous phase) ratio to be achieved with a relatively small amount of oil phase, resulting in a moisturizing feeling despite high viscosity, and a unique phase inversion sensation associated with the release of the internal aqueous phase upon application to the skin. This composition also contains, as a surfactant for emulsifying the internal aqueous phase in the oil phase, one or more selected from the group consisting of polyglycerol fatty acid esters of glycerin having an average degree of polymerization of 2 to 9 and polyethylene glycol dipolyhydroxystearate.

[0014] The W / O / W emulsion composition of the present invention has a structure in which a W / O emulsion is dispersed in an external aqueous phase.

[0015] In the W / O emulsion of the present invention, which forms the internal phase, an osmolality adjuster is contained in the aqueous phase, which is the innermost phase. The osmolality adjuster of the present invention comprises at least one selected from the group consisting of citric acid, citrates, and sulfates, preferably citrates, and more preferably sodium citrate. The amount of the osmolality adjuster of the present invention relative to the total amount of the emulsion composition is preferably 0.01 to 0.5 wt %, more preferably 0.02 to 0.2 wt %.

[0016] In the present invention, the internal aqueous phase and the oil phase are emulsified with one or more surfactants selected from the group consisting of polyglycerol fatty acid esters of glycerol having an average degree of polymerization of 2 to 9 and polyethylene glycol dipolyhydroxystearate to form a W / O type emulsion.

[0017] According to one embodiment of the present invention, the W / O / W emulsion composition of the present invention contains, as a surfactant that emulsifies the internal aqueous phase in the oil phase, one or more polyglycerol fatty acid esters having an average degree of polymerization of glycerin of 2 to 9. The polyglycerol fatty acid ester of the present invention having an average degree of polymerization of glycerin of 2 to 9 is preferably one or more polyglycerol fatty acid esters having an average degree of polymerization of glycerin of 2 to 9 selected from the group consisting of polyglyceryl oleate, polyglyceryl isostearate, polyglyceryl diisostearate, polyglyceryl dipolyhydroxystearate, and polyglyceryl polyricinoleate, more preferably one or more polyglycerol fatty acid esters selected from the group consisting of polyglyceryl-4 oleate, polyglyceryl-6 oleate, polyglyceryl-2 isostearate, polyglyceryl-6 polyricinoleate, polyglyceryl-2 diisostearate, and polyglyceryl-2 dipolyhydroxystearate, more preferably polyglyceryl-6 polyricinoleate.

[0018] According to another embodiment of the present invention, the W / O / W emulsion composition of the present invention comprises, as a surfactant that emulsifies the internal aqueous phase in the oil phase, one or more polyglycerol fatty acid esters having an average degree of polymerization of glycerin of 2 to 9. The polyglycerol fatty acid ester of the present invention having an average degree of polymerization of glycerin of 2 to 9 is preferably one or more polyglycerol fatty acid esters having an average degree of polymerization of glycerin of 2 to 9 selected from the group consisting of polyglyceryl oleate, polyglyceryl isostearate, polyglyceryl diisostearate, polyglyceryl dipolyhydroxystearate, and polyglyceryl polyricinoleate, and such polyglycerol fatty acid esters more preferably contain at least one OH group in the main chain of the fatty acid residue, such as polyglyceryl-6 polyricinoleate.

[0019] According to another embodiment of the present invention, the W / O / W emulsion composition of the present invention contains one or more polyethylene glycol dipolyhydroxystearates as a surfactant that emulsifies the internal aqueous phase in the oil phase.

[0020] According to one preferred embodiment of the present invention, the W / O / W emulsion composition of the present invention contains, as a surfactant that emulsifies the internal aqueous phase in the oil phase, one or more polyglycerol fatty acid esters of glycerin having an average degree of polymerization of 2 to 9.

[0021] In the W / O / W emulsion composition of the present invention, the surfactant selected from the group consisting of one or more polyglycerol fatty acid esters of glycerol having an average degree of polymerization of 2 to 9 and polyethylene glycol dipolyhydroxystearate may be commercially available, if available.

[0022] The amount of the surfactant selected from the group consisting of one or more polyglycerol fatty acid esters of glycerol having an average degree of polymerization of 2 to 9 and polyethylene glycol dipolyhydroxystearate in the W / O / W emulsion composition of the present invention is not limited, but is preferably 0.5 to 2% by weight.

[0023] According to one preferred embodiment of the present invention, the W / O / W emulsion composition of the present invention contains one or more oils selected from the group consisting of polar oils having an IOB value of 0.1 to 0.8. Such oils are commonly used in cosmetics, pharmaceuticals, foods, etc., and are preferably one or more oils selected from the group consisting of pentaerythristyl tetraethylhexanoate, glyceryl diisostearate, di(phytosteryl / octyldodecyl) lauroyl glutamate, bis-diglyceryl polyacyladipate-2, dipentaerythristyl hexahydroxystearate, and castor oil, and more preferably one or more oils selected from the group consisting of castor oil, bis-diglyceryl polyacyladipate-2, and dipentaerythristyl hexahydroxystearate. The IOB value is an abbreviation for Inorganic / Organic Balance, and is a value representing the ratio of inorganic value to organic value, serving as an index of the degree of polarity of an organic compound. Specifically, the IOB value is expressed as "IOB value = inorganic value / organic value." Here, the "inorganic value" and "organic value" are set according to the type of atom or functional group, such as 20 for one carbon atom in a molecule and 100 for one hydroxyl group in a molecule. The IOB value of an organic compound can be calculated by integrating the "inorganic values" and "organic values" of all atoms and functional groups in the organic compound (see, for example, Fujita, "Chemical Region," Vol. 11, No. 10, pp. 719-725, 1957).

[0024] In the W / O / W emulsion composition of the present invention, the amount of one or more oils selected from the group consisting of polar oils having an IOB value of 0.1 to 0.8 relative to the total amount of the composition is not particularly limited, but is preferably 3 to 20 wt %, more preferably 5 to 10 wt %. The W / O / W emulsion composition of the present invention may further contain an oil typically used in cosmetics, pharmaceuticals, foods, etc. Examples of such oils include, but are not limited to, hydrocarbon oils, ester oils, silicone oils, higher alcohols having 12 to 22 carbon atoms, fatty acids having 12 to 22 carbon atoms, and fats and oils.

[0025] Examples of hydrocarbon oils in the present invention include liquid paraffin, squalane, squalene, pristane, paraffin, isoparaffin, hydrogenated polyisobutene, olefin oligomers, and volatile hydrocarbon oils (e.g., isododecane, isohexadecane, undecane, tridecane, etc.).

[0026] Examples of the ester oils in the present invention include isopropyl myristate, cetyl ethylhexanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, isocetyl stearate, isocetyl isostearate, cholesteryl 12-hydroxystearate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid esters, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, glycerin di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, glycerin triisostearate, pentaerythritol tetraethylhexanoate, Ingredients: Triethylhexanoin (glyceryl tri-2-ethylhexanoate), cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glycerin trimyristate, tri-2-heptylundecanoic acid glyceride, castor oil fatty acid methyl ester, oleyl oleate, cetostearyl alcohol, acetoglyceride, 2-heptylundecyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamine Examples of triester oils include 2-octyldodecyl adipate, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, polypropylene glycol dipivalate, ethyl acetate, butyl acetate, amyl acetate, and triethyl citrate.

[0027] Examples of silicone oils in the present invention include linear polysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane, and methylhydrogenpolysiloxane, and cyclic polysiloxanes such as decamethylpolysiloxane, dodecamethylpolysiloxane, and tetramethyltetrahydrogenpolysiloxane.

[0028] In the present invention, examples of the higher alcohol having 12 to 22 carbon atoms include oleyl alcohol, 2-decyltetradecynol, dodecanol, isostearyl alcohol, octyldodecanol, etc. Examples of the fatty acid having 12 to 22 carbon atoms include oleic acid, isostearic acid, linoleic acid, linolenic acid, etc.

[0029] Examples of fats and oils in the present invention include cacao butter, avocado oil, camellia oil, macadamia nut oil, corn oil, olive oil, rapeseed oil, sesame oil, persic oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, Chinese tung oil, Japanese tung oil, jojoba oil, germ oil, triglycerin, glycerin trioctanoate, glycerin triisopalmitate, and the like.

[0030] According to one preferred embodiment of the present invention, the W / O / W emulsion composition of the present invention further comprises a thickener having an alkyl group. Such a thickener having an alkyl group is not limited as long as it is a compound having an alkyl group and can be used as a thickener. It is contained in the external aqueous phase to disperse the oil phase (W / O emulsion) in the external aqueous phase. The amount of the thickener having an alkyl group in the present invention is preferably 0.01 to 2 wt % based on the total weight of the emulsion composition. The thickener having an alkyl group in the present invention is not limited, but is preferably one or more selected from the group consisting of alkyl-modified carboxyvinyl polymer, ammonium acryloyldimethyltaurate / beheneth-25 methacrylate crosspolymer, and acrylates / steareth-20 methacrylate copolymer.

[0031] The alkyl-modified carboxyvinyl polymer in the present invention is preferably an (acrylates / C10-30 alkyl acrylate) crosspolymer, and acts as an emulsifier and thickener. The alkyl-modified carboxyvinyl polymer in the present invention is not limited, but preferably has a molecular weight of about 500,000 to 3,000,000. As the alkyl-modified carboxyvinyl polymer in the present invention, commercially available products may be used, and for example, "CARBOPOL 1342," "PEMULEN TR-1," or "PEMULEN TR-2" (all manufactured by Lubrizol) may be used.

[0032] According to one preferred embodiment of the present invention, the W / O / W emulsion composition of the present invention may contain a polyol in the external aqueous phase and / or the internal aqueous phase. Examples of such polyols include glycerin, 1,3-butylene glycol, and dipropylene glycol. The amount of such polyols is preferably 5 to 25 wt % of the total weight of the emulsion composition.

[0033] The W / O / W emulsion composition of the present invention may further contain, as necessary, optional additive components that are typically incorporated into cosmetics, etc., within the scope of not impairing the effects of the present invention. Examples of such additive components include thickeners such as cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, methylhydroxypropyl cellulose, methylcellulose, carboxymethyl cellulose, quince seed, carrageenan, pectin, mannan, curdlan, chondroitin sulfate, starch, galactan, dermatan sulfate, glycogen, gum arabic, heparan sulfate, hyaluronic acid, sodium hyaluronate, tragacanth gum, keratan sulfate, chondroitin, xanthan gum, mucoitin sulfate, hydroxyethyl guar gum, carboxymethyl guar gum, guar gum, dextran, keratosulfuric acid, locust bean gum, succinoglucan, caronic acid, chitin, chitosan, carboxymethyl chitin, and agar; lower alcohols such as ethanol; acids such as butylhydroxytoluene, tocopherol, and phytin. antibacterial agents such as benzoic acid, salicylic acid, sorbic acid, parahydroxybenzoic acid alkyl esters, and hexachlorophene; benzoic acid-based ultraviolet absorbers such as para-aminobenzoic acid (hereinafter abbreviated as "PABA"), PABA monoglycerin ester, N,N-dipropoxy PABA ethyl ester, N,N-diethoxy PABA ethyl ester, N,N-dimethyl PABA methyl ester, N,N-dimethyl PABA ethyl ester, N,N-dimethyl PABA butyl ester, and N,N-dimethyl PABA 2-ethylhexyl ester; anthranilic acid-based ultraviolet absorbers such as homomenthyl-N-acetylanthranilate; salicylic acid-based ultraviolet absorbers such as amyl salicylate, menthyl salicylate, homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, and p-isopropanol phenyl salicylate;Octyl cinnamate, ethyl 4-isopropyl cinnamate, methyl 2,5-diisopropyl cinnamate, ethyl 2,4-diisopropyl cinnamate, methyl 2,4-diisopropyl cinnamate, propyl p-methoxycinnamate, isopropyl p-methoxycinnamate, isoamyl p-methoxycinnamate, octyl p-methoxycinnamate (2-ethylhexyl p-methoxycinnamate), 2-ethoxyethyl p-methoxycinnamate, cyclohexyl p-methoxycinnamate, ethyl α-cinnamate Cinnamic acid-based ultraviolet absorbers such as cyano-β-phenylcinnamate, 2-ethylhexyl-α-cyano-β-phenylcinnamate, and glyceryl mono-2-ethylhexanoyl-di-paramethoxycinnamate; [3-bis(trimethylsiloxy)methylsilyl-1-methylpropyl]-3,4,5-trimethoxycinnamate, [3-bis(trimethylsiloxy)methylsilyl-3-methylpropyl]-3,4,5-trimethoxycinnamate, [3-bis(trimethylsiloxy)methylsilylpropyl]-3,4,5-trimethoxycinnamate, [3 silicone-based cinnamic acid ultraviolet absorbers such as [3-bis(trimethylsiloxy)methylsilylbutyl]-3,4,5-trimethoxycinnamate, [3-tris(trimethylsiloxy)silylbutyl]-3,4,5-trimethoxycinnamate, [3-tris(trimethylsiloxy)silylbutyl]-3,4,5-trimethoxycinnamate, and [3-tris(trimethylsiloxy)silyl-1-methylpropyl]-3,4-dimethoxycinnamate; 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'- benzophenone-based ultraviolet absorbers such as dihydroxy-4,4'-dimethoxybenzophenone, 2,2'4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, 4-phenylbenzophenone, 2-ethylhexyl-4'-phenyl-benzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, and 4-hydroxy-3-carboxybenzophenone;UV-absorbing agents such as 3-(4'-methylbenzylidene)-d,l-camphor, 3-benzylidene-d,l-camphor, urocanic acid ethyl ester, 2-phenyl-5-methylbenzoxazole, 2,2'-hydroxy-5-methylphenylbenzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, dibenzalazine, dianisoylmethane, 4-methoxy-4'-t-butyldibenzoylmethane, and 5-(3,3'dimethyl-2-norbornylidene)-3-pentan-2-one. absorbents; organic acids such as acyl sarcosinate (e.g., sodium lauroyl sarcosinate), glutathione, citric acid, malic acid, tartaric acid, and lactic acid; vitamin A and its derivatives, vitamin B6 hydrochloride, vitamin B6 tripalmitate, vitamin B6 dioctanoate, vitamin B2 and its derivatives, vitamin B12, vitamin B15 and its derivatives, etc.; vitamin E such as α-tocopherol, β-tocopherol, γ-tocopherol, and vitamin E acetate, vitamin D, vitamin H, pantothenic acid, pantethine, nicotinamide, and benzyl nicotinate;γ-oryzanol, allantoin, glycyrrhizic acid (salt), glycyrrhetinic acid and its derivatives, tranexamic acid and its derivatives (including tranexamic acid derivatives such as tranexamic acid dimers (e.g., trans-4-(trans-aminomethylcyclohexanecarbonyl)aminomethylcyclohexanecarboxylic acid hydrochloride, etc.), esters of tranexamic acid and hydroquinone (e.g., trans-4-aminomethylcyclohexanecarboxylic acid 4'-hydroxyphenyl ester, etc.), esters of tranexamic acid and gentisic acid (e.g., 2-(trans-4-aminomethylcyclohexylcarbonyloxy)-5-hydroxybenzoic acid and its salts, etc.), amides of tranexamic acid (e.g., trans-4-aminomethylcyclohexanecarboxylic acid methylamide and its salts, trans-4-(P-methoxybenzoyl)aminomethylcyclohexanecarboxylic acid and its salts, trans-4-guanidinomethylcyclohexanecarboxylic acid and its salts, etc.)], saponins such as hinokitiol, bisabolol, eucalptone, thymol, inositol, saikosaponin, carrot saponin, loofah saponin, and soapberry saponin, various drugs such as pantothenyl ethyl ether, ethinyl estradiol, tranexamic acid, arbutin, cepharanthine, and placenta extract; Rumex dock, Sophora flavescens, and watercress, Extracts of plants such as orange, sage, yarrow, mallow, Swertia jasmine, thyme, Angelica sinensis, spruce, birch, horsetail, loofah, horse chestnut, saxifrage, arnica, lily, mugwort, peony, aloe, gardenia, and sawara; pigments; porous and / or water-absorbent powders (for example, starches obtained from corn, potato, etc., silicic anhydride, talc, kaolin, aluminum magnesium silicate, calcium alginate, etc.);Examples of suitable surfactants include nonionic surfactants such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan sesquioleate, sorbitan trioleate, polyoxyethylene sorbitan monolaurate, polyoxetylene sorbitan monostearate, polyethylene glycol monooleate, polyoxyethylene alkyl ethers, polyglycol diethers, lauroyl diethanolamide, fatty acid isopropanolamide, maltitol hydroxy fatty acid ethers, alkylated polysaccharides, alkyl glucosides, and sugar esters; cationic surfactants such as stearyl trimethylammonium chloride and benzalkonium chloride laurylamine oxide; anionic surfactants such as sodium palmitate, sodium laurate, sodium laurate, potassium lauryl sulfate, alkyl triethanolamine sulfate ether, turmeric oil, linear dodecyl benzene sulfate, polyoxyethylene hydrogenated castor oil maleic acid, and acyl methyl taurine; amphoteric surfactants; neutralizers; preservatives; fragrances; and pigments.

[0034] The method for producing the W / O / W emulsion composition of the present invention is not particularly limited, and the composition can be produced by a conventional method, for example, by preparing a W / O emulsion produced by stirring and mixing using an emulsifying machine such as a homomixer or a disper, and then mixing and emulsifying this with an external aqueous phase.

[0035] The composition of the present invention may be a cosmetic composition. The cosmetic composition in the present invention means a composition used for the purpose of applying makeup.

[0036] 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 % by weight unless otherwise specified.

[0037] W / O / W emulsion compositions were prepared using four different osmolality adjusters (sodium L-glutamate, sodium citrate, magnesium sulfate, and magnesium chloride) as shown in Table 1 below. The W / O / W emulsion compositions were obtained by adding an aqueous phase containing an osmolality adjuster to an oil phase containing a surfactant, emulsifying the mixture using a homomixer, and then adding the resulting W / O emulsion to the external aqueous phase and dispersing it with a disperser. The viscosity of each sample was measured the next day at a sample temperature of 30°C using a VISCOMETER TVB-15 (manufactured by Toki Sangyo Co., Ltd.) with a rotor No. 7 and 10 rpm. The pH and particle size of the emulsified particles were also measured. The viscosity of each sample was also measured after storage under various conditions. A rating of A was given if the viscosity after four weeks at 50°C or the next day was 70% or more, B if it was 50 to less than 70%, C if it was 30 to less than 50%, and D if it was less than 30% or separated. A rating of B or higher was considered a pass. The results are shown in Table 1.

[0038] The results in Table 1 show that the W / O / W emulsion compositions of Test Examples 2 and 3 showed relatively little change in viscosity over time, particularly at high temperatures, and exhibited good stability.

[0039] Next, various concentrations of sodium citrate were used to prepare W / O / W emulsion compositions as shown in Table 2 below. The changes in viscosity over time, pH, and particle size of the emulsion particles were evaluated using the same methods and evaluation criteria as above. The results are shown in Table 2.

[0040] The results in Table 2 show that the W / O / W emulsion compositions of Test Examples 5 to 7 showed little change in viscosity over time at various temperatures and exhibited good stability.

Claims

1. A W / O / W type emulsion composition comprising an inner aqueous phase, an oil phase in which the inner aqueous phase is dispersed, and an outer aqueous phase in which the oil phase is dispersed, wherein the inner aqueous phase contains an osmotic pressure regulator, and the osmotic pressure regulator generates an osmotic pressure between the inner aqueous phase and the outer aqueous phase, and as a surfactant for emulsifying the inner aqueous phase into the oil phase, the composition contains one or more selected from the group consisting of polyglycerol fatty acid esters having an average degree of polymerization of glycerin of 2 to 9 and polyethylene glycol dipolyhydroxystearate, and the osmotic pressure regulator contains at least one selected from the group consisting of citric acid, citrate and sulfate.

2. The composition according to claim 1, wherein the compounding amount of the osmotic pressure regulator with respect to the composition is 0.01 to 0.5% by weight.

3. The composition according to claim 1, wherein as a surfactant for emulsifying the inner aqueous phase into the oil phase, the composition contains one or more polyglycerol fatty acid esters selected from the group consisting of polyglyceryl oleate, polyglyceryl isostearate, polyglyceryl diisostearate, polyglyceryl dipolyhydroxystearate and polyglyceryl polyricinoleate having an average degree of polymerization of glycerin of 2 to 9.

4. The composition according to claim 3, wherein the surfactant for emulsifying the inner aqueous phase into the oil phase contains at least one OH group in the main chain of the fatty acid residue.

5. The composition according to claim 1, wherein as a surfactant for emulsifying the inner aqueous phase into the oil phase, the composition contains one or more polyglycerol fatty acid esters selected from the group consisting of polyglyceryl-4 oleate, polyglyceryl-6 oleate, polyglyceryl-2 isostearate, polyglyceryl-6 polyricinoleate, polyglyceryl-2 diisostearate, and polyglyceryl-2 dipolyhydroxystearate.

6. The composition according to claim 1, wherein as a surfactant for emulsifying the inner aqueous phase into the oil phase, the composition contains polyglyceryl-6 polyricinoleate.

7. The composition according to claim 1, wherein the oil phase contains one or more oil components selected from the group consisting of polar oils having an IOB value of 0.1 to 0.

8.

8. The composition according to claim 7, wherein the oil component is one or more selected from the group consisting of castor oil, bis-diglyceryl polyacyl adipate-2, and dipentaerythrityl hexahydroxystearate.

9. The composition according to claim 7, wherein the content of the oil component in the composition is 3 to 20% by weight.

10. The composition according to claim 1, wherein the external aqueous phase contains a thickener having an alkyl group.

11. The composition according to claim 10, wherein the thickener having an alkyl group is at least one selected from the group consisting of an alkyl-modified carboxyvinyl polymer, acryloyldimethyltaurine ammonium / beheneth-25 methacrylate cross-polymer, and (acrylates / steareth-20 methacrylate) copolymer.

12. The composition according to any one of claims 1 to 11, which is a cosmetic composition.

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