Oil-in-water emulsion composition

Abstract

To provide an oil-in-water emulsion composition that can form a Pickering emulsion particle of a size that allows a visual inspection.SOLUTION: An oil-in-water emulsion composition includes a component (A): octenyl succinate starch ester metal salt, a component (B): one or more oil-based components selected from the group consisting of hydrocarbon oil, fatty acid triglyceride, and vegetable oil, a component (C): PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin, and a component (D): water. A mass ratio of the component (B) to the component (A) [component (B) / component (A)] is 0.45-1.0. A content of the component (C) is 0.05-20.0 mass%. The oil-in-water emulsion composition is a Pickering emulsion constituted by an aqueous phase including the component (D) and an oil phase including the component (B).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an oil-in-water emulsion composition. [Background technology]

[0002] By dispersing visible particles in liquid cosmetics such as body lotions, refreshing cosmetics, and deodorants, the cosmetics can be given a unique appearance, which is expected to create new aesthetic value for consumers and greatly stimulate demand.

[0003] Particles used in cosmetics include scrubbing agents, and it is conceivable to use large-sized particles of these. Also, calcium alginate capsules are known as large-sized particles.

[0004] However, large scrubs irritate the skin when applied and can cause discomfort after application. Calcium alginate capsules also have the problem of clumps remaining on the skin after application, causing discomfort.

[0005] On the other hand, so-called Pickering emulsions are known, in which oil droplets are stabilized by powder and contain no surfactant or only a small amount of surfactant (for example, Patent Documents 1 to 4). When a Pickering emulsion is used, Pickering emulsion particles are present in the cosmetic, but the particles do not remain on the skin after application, so there is no discomfort. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-95638 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-95639 [Patent Document 3] Japanese Patent Application Laid-Open No. 2018-188497 [Patent Document 4] Japanese Patent Application Publication No. 2019-202962 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the Pickering emulsion particles disclosed in Patent Documents 1 to 4 have a volume particle size of about 100 μm or less, and Pickering emulsion particles large enough to be visible in particle shape have not been obtained.

[0008] Therefore, an object of the present invention is to provide an oil-in-water emulsion composition capable of forming Pickering emulsion particles of a visible size. [Means for solving the problem]

[0009] As a result of intensive research to achieve the above-mentioned object, the present inventors have found that visually visible Pickering emulsion particles can be formed using an oil-in-water emulsion cosmetic that contains component (A): a metal salt of a starch octenylsuccinate ester, component (B): one or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils, component (C): PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin, and component (D): water, wherein the mass ratio of component (B) to component (A) [component (B) / component (A)] and the content of component (C) are within specific ranges, and the cosmetic is a Pickering emulsion having an aqueous phase containing component (D) and an oil phase containing component (B). The present invention was completed based on these findings.

[0010] That is, the present invention provides a composition comprising the following components (A), (B), (C), and (D): the mass ratio of the component (B) to the component (A) [component (B) / component (A)] is 0.45 to 1.0; The content of the component (C) is 0.05 to 20.0 mass %, The present invention provides an oil-in-water emulsion composition, which is a Pickering emulsion having an aqueous phase containing the above-mentioned component (D) and an oil phase containing the above-mentioned component (B). Component (A): Octenyl succinic acid starch ester metal salt Component (B): One or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils. Ingredient (C): PEG / PPG / Polybutylene Glycol-8 / 5 / 3 Glycerin Ingredient (D): Water

[0011] The oil-in-water emulsion composition preferably contains a colorant.

[0012] The content of the component (D) is preferably 50.0 to 99.96% by mass.

[0013] The total content of the components (A) and (B) is preferably 30.0 mass % or less.

[0014] The oil-in-water emulsion composition may or may not contain ethanol, and the ethanol content is preferably 30.0% by mass or less. [Effects of the Invention]

[0015] In the oil-in-water emulsion composition of the present invention, the presence of Pickering emulsion particles can be visually confirmed. Therefore, such an oil-in-water emulsion composition exhibits a unique appearance and can provide new aesthetic value to consumers. Furthermore, the oil-in-water emulsion composition of the present invention can form Pickering emulsions of a visible size even when ethanol is contained in a small amount or is not blended at all. DETAILED DESCRIPTION OF THE INVENTION

[0016] The oil-in-water emulsion composition of the present invention contains at least a metal salt of starch octenyl succinate, one or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils, PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin, and water. In this specification, the metal salt of starch octenyl succinate may be referred to as "component (A)," the one or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils as "component (B)," the PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin as "component (C)," and water as "component (D)."

[0017] That is, the oil-in-water emulsion composition of the present invention contains at least component (A), component (B), component (C), and component (D). The oil-in-water emulsion composition of the present invention may contain components other than the above components (A) to (D). Furthermore, each of the components contained in the oil-in-water emulsion composition of the present invention, for example, component (A), component (B), component (C), and other components, may be used singly or in combination of two or more.

[0018] The oil-in-water emulsion composition of the present invention is a Pickering emulsion having an aqueous phase containing component (D) and an oil phase (oil droplets) containing component (B) dispersed in the aqueous phase. The Pickering emulsion has a structure in which component (A) is present at the interface between the aqueous phase and the oil phase.

[0019] [Component (A)] Component (A) is a metal salt of starch octenyl succinate. The oil-in-water emulsion composition of the present invention can form a Pickering emulsion by using component (A) in combination with components (B), (C), and (D). Furthermore, it can impart a smooth feel to the skin when applied to it. Only one type of component (A) may be used, or two or more types may be used.

[0020] Examples of the metal salt of starch octenylsuccinate include aluminum salt, calcium salt, barium salt, and iron salt of starch octenylsuccinate. Among these, aluminum salt (aluminum starch octenylsuccinate) is preferred. The aluminum starch octenylsuccinate may be referred to as starch octenylsuccinate Al or corn starch octenylsuccinate aluminum. The aluminum starch octenylsuccinate may also be referred to as ALUMINUM STARCH OCTENYLSUCCINATE under the INCI (International Nomenclature for Cosmetic Ingredients) name.

[0021] In the oil-in-water emulsion composition of the present invention, component (A) is in the form of a powder. When heated to a relatively high temperature (e.g., 60°C or higher), metal salts of starch octenyl succinate are hydrophilized and gelled (so-called gelatinization or gelatinization), losing their powdery state, and may be used as a thickener. The oil-in-water emulsion composition of the present invention is characterized in that component (A) is contained in the form of a powder. For this reason, in the process for producing the oil-in-water emulsion composition of the present invention, component (A) is preferably used at a temperature below 60°C (more preferably below 55°C).

[0022] Component (A) can also be a commercially available product, such as those sold under the trade names "DRY-FLO PURE" and "DRY-FLO PC" (both manufactured by Nouryon) and "Octie" (manufactured by Nippon Starch Chemical Co., Ltd.).

[0023] The content of component (A) in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 0.005 to 20.0% by mass, more preferably 0.01 to 15.0% by mass, and even more preferably 0.05 to 10.0% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. When the content is 0.005% by mass or more, large-sized Pickering emulsions are more likely to be formed. Furthermore, oil floating (the floating of oily components not contained in emulsion particles to form an oil phase on the surface of the composition) is more unlikely to occur. When the content is 20.0% by mass or less, free component (A) that does not contribute to emulsion particles is less likely to be generated, and the aqueous phase is less likely to become cloudy. The content of component (A) is the total content of all components (A) in the oil-in-water emulsion composition of the present invention.

[0024] [Component (B)] Component (B) is one or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils. By incorporating component (B) as the oily component into the oil-in-water emulsion composition, a large-sized oil-in-water Pickering emulsion having an aqueous phase containing component (D) and an oil phase containing component (B) can be formed. Among these, fatty acid triglycerides and vegetable oils are preferred as component (B) from the viewpoints of forming a Pickering emulsion with a clearer outline and reducing the likelihood of oil floating. Only one type of component (B) may be used, or two or more types may be used.

[0025] Examples of the hydrocarbon oil include isoparaffin, light isoparaffin, light liquid isoparaffin, squalane, synthetic squalane, vegetable squalane (sugar squalane, olive squalane, etc.), liquid isoparaffin, liquid paraffin, hydrogenated polyisobutene, isododecane, and mineral oil.

[0026] The fatty acid triglyceride may be a natural fatty acid triglyceride or a synthetic fatty acid triglyceride. For example, vegetable oils often contain natural fatty acid triglycerides.

[0027] The fatty acid triglyceride is preferably one in which one or more constituent fatty acids have 6 to 22 carbon atoms.

[0028] Examples of the fatty acid triglycerides include glyceryl tri-2-ethylhexanoate, glyceryl tricaprylate, glyceryl tricaprate, glyceryl triundecylate, glyceryl tristearate, glyceryl triisostearate, glyceryl tripalmitate, glyceryl triundecanoate, glyceryl tri-2-heptylundecanoate, glyceryl tribehenate, glyceryl trimyristate, glyceryl trilaurate, glyceryl trioleate, glyceryl trilinoleate, tripalmiate, glyceryl triisostearate ... Glyceryl Acetate, Glyceryl Triacetyl Hydroxystearate, Glyceryl Triacetylricinoleate, Glyceryl Trihydroxystearate, Caprylic / Capric Triglyceride, Caprylic / Capric / Myristic / Stearic Triglyceride, Caprylic / Capric / Isostearic / Adipic Triglyceride, Caprylic / Capric / Lauric Triglyceride, Caprylic / Capric / Linoleic Triglyceride, Caprylic / Capric Triglyceride Glyceryl Phosphate / Stearate, Glyceryl Tritallowate, Glyceryl Tallowate / Mink Oil / Cod Liver Oil Triglyceride, Glyceryl Trimink Oil / Palmitate, Glyceryl Tricoconut Oil, Glyceryl Trilanolinate, Glyceryl Triricinoleate / Caproate / Caprylate / Caprate, C10-18 Triglyceride, C12-18 Triglyceride, Hydrogenated C12-18 Triglyceride, C12-20 Triglyceride, Examples of fatty acids include C18-36 triglycerides, C10-40 tri-branched glycerides, C12-31 tri-branched glycerides, hydrogenated rosin / diisostearate glyceryl, palm / palm kernel / olive / macadamia / rapeseed glyceryl, castor / olive triglyceride, behenic / isostearic / eicosanedioic acid glyceryl, and mink triglyceride / palmitic acid glyceryl.

[0029] Examples of the vegetable oils include macadamia nut oil, eucalyptus oil, coconut oil, avocado oil, safflower oil, olive oil, palm oil, palm kernel oil, kukui nut oil, shea butter, cocoa butter, almond oil, sunflower oil, rosehip oil, camellia oil, kiwi fruit seed oil, camellia oil, apricot kernel oil, sesame oil, soybean oil, jojoba oil, castor oil, hazelnut oil, medlar oil, peppermint oil, argan oil, carrot oil, lavender oil, damask rose flower wax, rosa centifolia flower wax, jasmine flower wax, grapeseed oil, linseed oil, walnut oil, yuzu seed oil, evening primrose oil, corn germ oil, grape oil, and hydrogenated versions thereof (e.g., hydrogenated castor oil, hydrogenated jojoba oil, hydrogenated palm oil, hydrogenated avocado oil, hydrogenated soybean oil, etc.).

[0030] From the viewpoint of the stability over time of the Pickering emulsion, component (B) preferably contains macadamia nut oil, avocado oil, olive oil, shea butter, almond oil, sunflower oil, rosehip oil, apricot kernel oil, argan oil, grapeseed oil, linseed oil, walnut oil, yuzu seed oil, evening primrose oil, corn germ oil, and grape oil. The content of one or more selected from the group consisting of macadamia nut oil, avocado oil, olive oil, shea butter, almond oil, sunflower oil, rosehip oil, apricot kernel oil, argan oil, grapeseed oil, linseed oil, walnut oil, yuzu seed oil, evening primrose oil, corn germ oil, and grape oil in component (B) is preferably 90.0 to 100% by mass, more preferably 95.0 to 100% by mass, and even more preferably 100% by mass, relative to 100% by mass of the total amount of component (B).

[0031] The content of component (B) in the oil-in-water emulsion composition of the present invention is preferably 0.005 to 20.0 mass%, more preferably 0.01 to 15.0 mass%, and even more preferably 0.05 to 10.0 mass%, relative to 100 mass% of the oil-in-water emulsion composition of the present invention. When the content is 0.005 mass% or more, a more stable Pickering emulsion is formed. When the content is 20.0 mass% or less, emulsion aggregation is less likely to occur. The content of component (B) is the total content of all components (B) in the oil-in-water emulsion composition of the present invention.

[0032] In the oil-in-water emulsion composition of the present invention, the mass ratio of component (B) to component (A) [component (B) / component (A)] is 0.45 to 1.0, preferably 0.5 to 0.95, and more preferably 0.6 to 0.9. When the mass ratio is 0.45 or more, the fluidity of the oil phase is sufficiently high, and a Pickering emulsion particle shape can be formed. When the mass ratio is 1.0 or less, oil floating can be suppressed.

[0033] [Component (C)] Component (C) is PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin. That is, component (C) is an ether of glycerin with polyethylene glycol, polypropylene glycol, and polybutylene glycol. Component (C) is sometimes written as polyoxybutylene polyoxyethylene polyoxypropylene glyceryl ether (3B.O.) (8E.O.) (5P.O.). Component (C) is also sometimes written as PEG / PPG / POLYBUTYLENE GLYCOL-8 / 5 / 3 GLYCERIN in its INCI name. The inclusion of component (C) can increase the size of the Pickering emulsion formed. Component (C) may be used alone or in combination.

[0034] Commercially available products can also be used as component (C). Examples of commercially available products containing component (C) include those under the trade names "Wilbride S-753" and "Wilbride S-753D" (both manufactured by NOF Corporation).

[0035] The content of component (C) in the oil-in-water emulsion composition of the present invention is 0.05 to 20.0% by mass, preferably 0.1 to 15.0% by mass, and more preferably 0.3 to 10.0% by mass, based on 100% by mass of the oil-in-water emulsion composition of the present invention. A content of 0.05% by mass or more suppresses emulsion coalescence, enabling the formation of large-sized Pickering emulsions. If the content exceeds 20.0% by mass, the affinity between the water phase and the oil phase increases, making it impossible to stably form a Pickering emulsion. The content of component (C) is the total content of all components (C) in the oil-in-water emulsion composition of the present invention.

[0036] [Component (D)] Component (D) is water, and is not particularly limited, but is preferably purified water. Component (D) is a component that forms the aqueous phase (matrix) of the oil-in-water Pickering emulsion in the oil-in-water emulsion composition of the present invention.

[0037] The content of component (D) in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 50.0 to 99.96 mass%, more preferably 55.0 to 97.0 mass%, and even more preferably 60.0 to 95.0 mass%, relative to 100 mass% of the oil-in-water emulsion composition of the present invention. When the content is within the above range, an oil-in-water Pickering emulsion can be formed more stably.

[0038] The oil-in-water emulsion composition of the present invention may further contain polyglyceryl-10 decaisostearate. Polyglyceryl-10 decaisostearate is designated by the INCI name Polyglyceryl-10 Decaisostearate. Polyglyceryl-10 decaisostearate is an ester compound synthesized from a decamer of glycerin and 10 equivalents of isostearic acid, and has a hydrophilic portion derived from two hydroxyl groups and 10 ester groups per molecule, and a lipophilic portion derived from an isostearyl group. It is presumed that polyglyceryl-10 decaisostearate adheres to component (A) via the hydrophilic portion and enhances the hydrophobicity of component (A) via the lipophilic portion. As a result, the release of component (A) from the emulsion particles is reduced, which is presumed to further suppress the cloudiness of the aqueous phase in the oil-in-water emulsion composition, resulting in a more aesthetically pleasing appearance. The polyglyceryl-10 decaisostearate may be used singly or in combination of two or more.

[0039] The content of polyglyceryl-10 decaisostearate in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 0.0005 to 1.0% by mass, more preferably 0.001 to 0.5% by mass, and even more preferably 0.001 to 0.3% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. When the content is 0.0005% by mass or more, the effect of suppressing clouding of the aqueous phase is further improved. When the content is 1.0% by mass or less, the effect of suppressing aggregation of component (A) is further improved.

[0040] In the oil-in-water emulsion composition of the present invention, the mass ratio of polyglyceryl-10 decaisostearate to component (A) [polyglyceryl-10 decaisostearate / component (A)] is preferably 0.001 to 0.3, more preferably 0.005 to 0.25, and even more preferably 0.005 to 0.15. When this mass ratio is 0.001 or more, the effect of suppressing clouding of the aqueous phase is further improved. When the content ratio is 0.3 or less, the effect of suppressing aggregation of component (A) is further improved.

[0041] From the viewpoint of achieving superior Pickering emulsion stability, the oil-in-water emulsion composition of the present invention preferably contains only a small amount of surfactant or is substantially free of surfactant. The surfactant content in the oil-in-water emulsion composition of the present invention is preferably 0.1% by mass or less (e.g., 0 to 0.1% by mass), more preferably 0.01% by mass or less, and even more preferably 0% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. When the surfactant content is 0.1% by mass or less, the formed oil-in-water Pickering emulsion can be more stable. Furthermore, when the oil-in-water emulsion composition of the present invention is used, stickiness, sliminess, and skin irritation upon application can be suppressed.

[0042] [Other ingredients] The oil-in-water emulsion composition of the present invention may contain components (other components) other than the above components (A) to (D). The other components are not particularly limited and include, for example, components commonly used in cosmetics and quasi-drugs. Specific examples include lower alcohols such as ethanol; oily components other than component (B); thickeners such as hydroxymethylcellulose, hydroxypropylmethylcellulose, and xanthan gum; polyhydric alcohols; moisturizers; pearlizing agents; anti-inflammatory agents such as glycyrrhizic acid and its salts; cooling agents such as menthol; pH adjusters such as phosphoric acid and its salts, citric acid and its salts, lactic acid and its salts, sodium hydroxide, and triethanolamine; fragrances; ultraviolet absorbers; antioxidants; preservatives; sequestering agents; film-forming polymeric compounds; powders other than component (A); colorants such as dyes and pigments; vitamins; amino acids; astringents; whitening agents; animal and plant extracts; neutralizing agents; disinfectants; antiperspirant components; deodorizing components; acids; and alkalis. The above other components may each be used singly or in combination of two or more.

[0043] The oil-in-water emulsion composition of the present invention may contain ethanol. The oil-in-water emulsion composition of the present invention can form large-sized Pickering emulsions not only when it contains ethanol but also when it does not contain ethanol. Furthermore, by incorporating ethanol, it is possible to add oil-soluble components (organic components, etc.) while maintaining the existence of the Pickering emulsion particles. Furthermore, by incorporating ethanol, it is possible to impart quick-drying properties and a refreshing feel to the oil-in-water emulsion composition of the present invention.

[0044] The ethanol content in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 70.0% by mass or less, and more preferably 50.0% by mass or less, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. In the present invention, the ethanol content in the oil-in-water emulsion composition of the present invention can be 30.0% by mass or less, 10.0% by mass or less, 1.0% by mass or less, or 0% by mass (i.e., no ethanol is contained).

[0045] When the oil-in-water emulsion composition of the present invention contains a thickener, it can suspend large-sized Pickering emulsions in the system, resulting in excellent aesthetics. Examples of such thickeners include water-soluble polymers. Examples of such water-soluble polymers include cellulose-based thickeners such as hydroxymethylcellulose, hydroxypropylmethylcellulose, and crystalline cellulose (e.g., cellulose nanofiber); gum-based thickeners such as xanthan gum; and acrylic thickeners such as carboxyvinyl polymers, (acrylates / C10-30 alkyl acrylate) crosspolymers (acrylic acid / methacrylic acid ester copolymers), polyacrylate crosspolymer-6, alkyl acrylate copolymers, and (sodium acrylate / sodium acryloyldimethyltaurate) copolymers. Among these, from the viewpoint of being able to form a large-sized Pickering emulsion more stably, polyacrylate crosspolymer-6, acrylate alkyl copolymer, (sodium acrylate / sodium acryloyldimethyltaurate) copolymer), and crystalline cellulose (particularly, cellulose nanofiber) are preferred, and polyacrylate crosspolymer-6 and crystalline cellulose (particularly, cellulose nanofiber) are more preferred. The above thickeners may be used singly or in combination of two or more.

[0046] The oil-in-water emulsion composition of the present invention may further contain crystalline cellulose. The crystalline cellulose is preferably so-called cellulose nanofiber. The content of crystalline cellulose in the oil-in-water emulsion composition of the present invention is preferably 0.005 to 2.0% by mass, more preferably 0.01 to 1.8% by mass, and even more preferably 0.015 to 1.6% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. When the content is 0.005% by mass or more, a Pickering emulsion is more likely to be formed. When the content is 2.0% by mass or less, emulsion aggregation is less likely to occur.

[0047] The oil-in-water emulsion composition of the present invention may further contain polyacrylate crosspolymer-6. The INCI name for the polyacrylate crosspolymer-6 is POLYACRYLATE CROSSPOLYMER-6. By incorporating polyacrylate crosspolymer-6, Pickering emulsion particles can be kept suspended without settling, resulting in an excellent aesthetic appearance. Commercially available products of the polyacrylate crosspolymer-6 include, for example, the trade name "SEPIMAX ZEN" (manufactured by Seppic Pharmaceuticals).

[0048] The content of polyacrylate crosspolymer-6 in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 0.05 to 3.0% by mass, and more preferably 0.1 to 1.5% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. When the content is 0.05% by mass or more, Pickering emulsion particles are less likely to settle. When the content is 3.0% by mass or less, the feel during use is further improved.

[0049] When carboxyvinyl polymers, acrylic acid-methacrylic acid ester copolymers, etc. are used as thickeners, they are usually neutralized with a basic substance. Examples of basic substances include alkanolamines such as triethanolamine and monoethanolamine; inorganic bases such as ammonia, sodium hydroxide, and potassium hydroxide; and basic amino acids such as arginine. The amount of basic substance added is sufficient to neutralize the carboxyvinyl polymer, acrylic acid-methacrylic acid ester copolymer, etc., and can be appropriately adjusted depending on the type and amount of these components used.

[0050] When the oil-in-water emulsion composition of the present invention contains a thickener, the content of the thickener in the oil-in-water emulsion composition of the present invention is not particularly limited, but is preferably 0.001 to 4.0% by mass, more preferably 0.005 to 3.0% by mass, relative to 100% by mass of the oil-in-water emulsion composition of the present invention. The content of the thickener is the total content of all thickeners in the oil-in-water emulsion composition of the present invention.

[0051] When the oil-in-water emulsion composition of the present invention contains a colorant, the Pickering emulsion can be colored. By combining a colorant with a thickener, large colored Pickering emulsions can be suspended in the system, resulting in even more excellent aesthetics. Two or more colorants may be used, and in this case, Pickering emulsions of various colors can be present in the composition, resulting in particularly excellent aesthetics.

[0052] Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, isoprene glycol, 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, concentrated glycerin, diglycerin, and polyglycerin.

[0053] The antiperspirant component is, for example, a drug that suppresses sweat production by astringenting the skin, and examples of the antiperspirant component include aluminum chlorohydrate, aluminum chloride, aluminum potassium sulfate, aluminum sulfate, aluminum acetate, aluminum chlorohydrate allantoin, and zinc paraphenolsulfonate.

[0054] The disinfectant is, for example, an agent that suppresses the growth of normal skin bacteria that produce substances that cause body odor. Examples of the disinfectant include isopropylmethylphenol, benzalkonium chloride, benzethonium chloride, chlorhexidine hydrochloride, phenol, trichlorocarbanilide, chlorhexidine gluconate, triclosan, triclocarban, piroctone olamine, zinc pyrithione, salicylic acid, sorbic acid, and lysozyme chloride.

[0055] Examples of the cooling agent include menthol, menthyl glyceryl ether, menthyl lactate, camphor, eucalyptol, and icilin.

[0056] The oil-in-water emulsion composition of the present invention preferably contains Pickering emulsion particles having a diameter of 1 mm or more (preferably 1.5 mm or more, more preferably 2 mm or more). The diameter of the Pickering emulsion particles can be measured using, for example, an optical microscope.

[0057] The dosage form of the oil-in-water emulsion composition of the present invention is not particularly limited, and examples include lotion, mist, gel, spray (aerosol type, non-aerosol type), tube, sheet, roll-on, etc. The oil-in-water emulsion composition of the present invention has a good appearance and is therefore preferably used in the form of a lotion or gel.

[0058] The use of the oil-in-water emulsion composition of the present invention is not particularly limited, and it can be used for either skin (e.g., face, neck, scalp, shoulders, body, arms, elbows, palms, backs of hands, thighs, calves, knees, ankles, tops of feet, soles, etc.) or hair. That is, the oil-in-water emulsion composition of the present invention may be used as either a hair cosmetic or a skin cosmetic. Examples of the oil-in-water emulsion composition of the present invention include body odor suppressants (deodorants), refreshing cosmetics, lotions, hair cosmetics, and shaving cosmetics.

[0059] The oil-in-water emulsion composition of the present invention is not particularly limited and can be produced by known or conventional methods. For example, the components are mixed and stirred using a known stirring device such as a disper mixer or a paddle mixer. Particularly from the viewpoint of facilitating the formation of large, visible Pickering emulsion particles, the following method can be mentioned. First, component (A), component (B), and, if necessary, other oil-soluble components are blended to prepare a non-aqueous mixture substantially free of water. Next, component (C), component (D), and, if necessary, other water-soluble components are blended to prepare an aqueous mixture. Next, the non-aqueous mixture is added to the aqueous mixture, and the mixture is mixed and dispersed to prepare a Pickering emulsion.

[0060] The oil-in-water emulsion composition of the present invention forms Pickering emulsion particles by blending a metal salt of starch octenyl succinate [component (A)] and water [component (D)] with one or more oily components [component (B)] selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils. Furthermore, by blending PEG / PPG / polybutylene glycol-8 / 5 / 3 glycerin [component (C)] into the system at a specific content ratio, the mass ratio of components (A) and (B) is set within a specific range, thereby forming large, visible Pickering emulsion particles, resulting in excellent aesthetics and appearance. The oil-in-water emulsion composition of the present invention can form large Pickering emulsion particles even when the amount of ethanol is small or even when ethanol is not blended at all. Furthermore, by blending a colorant such as an oil-soluble dye, the Pickering emulsion particles can be colored, resulting in an oil-in-water emulsion composition with even better aesthetics. [Example]

[0061] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. The content ratios listed in the tables are the content ratios of each component (i.e., the content ratio of the active ingredient in each raw material, so-called pure content), and are expressed in "mass %" unless otherwise specified. In addition, "-" in the tables indicates that the component was not blended or that evaluation was not performed.

[0062] Examples and Comparative Examples Each composition of the Examples and Comparative Examples was prepared by a conventional method using the components (components (A) to (D)) and other components shown in the table.

[0063] (evaluation) The compositions obtained in the Examples and Comparative Examples were evaluated as follows, and the evaluation results are shown in the tables.

[0064] [Emulsion particle size] 1 mL of the uniformly dispersed composition was dropped into a 12-well multi-well plate, and the Pickering emulsion particles in five wells were observed at 40x magnification using a microscope (all-in-one fluorescent microscope "BZ-X800", manufactured by Keyence Corporation). Ten Pickering emulsion particles whose outer periphery was entirely contained within the region between the circumscribing circle of the emulsion and a concentric circle with a diameter 50% of that circumscribing circle were selected in descending order of circumscribing circle diameter for evaluation. The emulsion particle size was then evaluated based on the following criteria: [Evaluation criteria] Good (Good): The diameter of the circumscribed circle of all 10 Pickering emulsion particles is 1 mm or more. × (bad): For one or more out of ten particles, the diameter of the circumscribed circle of the Pickering emulsion particle is less than 1 mm, or no Pickering emulsion is formed.

[0065] [Table 1]

[0066] [Table 2]

[0067] [Table 3]

[0068] As shown in the table, the oil-in-water emulsion composition (Example) of the present invention was able to produce large, visible Pickering emulsion particles of 1 mm or more. The diameter of the circumscribed circle of all 10 Pickering emulsion particles in the Example was 2 mm or more. Furthermore, no oil floating was observed in the oil-in-water emulsion composition (Example) of the present invention. On the other hand, in Comparative Example 1, all emulsion particles coalesced. In Comparative Example 2, the oil phase and the aqueous phase mixed together, and no emulsion was formed. In Comparative Example 3, the Pickering emulsion could not be dispersed in the aqueous phase, and no emulsion was formed. In Comparative Example 4, the oil phase separated (oil floating), and no emulsion was formed.

[0069] Further, formulation examples of the oil-in-water emulsion composition of the present invention are shown below. Prescription example 1: Skin care emulsion Glycerin 10.0% by mass Polyacrylate crosspolymer-6 0.3% by mass Corn starch octenylsuccinate aluminum 1.5% by mass Avocado oil 1.0% by mass PEG / PPG / Polybutylene Glycol-8 / 5 / 3 Glycerin 5.0% by mass Fragrance 0.1% by mass water remainder Total 100.0% by mass

[0070] Formulation example 2: Deodorant Ethanol 30.0% by mass Isopropylmethylphenol 0.1% by mass Corn starch octenylsuccinate aluminum 2.0% by mass Rosehip oil 1.5% by mass PEG / PPG / Polybutylene Glycol-8 / 5 / 3 Glycerin 5.0% by mass Fragrance 0.1% by mass water remainder Total 100.0% by mass

[0071] Prescription example 3: Refreshing body gel Ethanol 30.0% by mass Menthol 0.4% by mass Corn starch octenylsuccinate aluminum 2.0% by mass Grapeseed oil 1.5% by mass PEG / PPG / Polybutylene Glycol-8 / 5 / 3 Glycerin 3.0% by mass Fragrance 0.1% by mass water remainder Total 100.0% by mass

Claims

1. The composition contains the following components (A), (B), (C), and (D), the mass ratio of the component (B) to the component (A) [component (B) / component (A)] is 0.45 to 1.0, The content of the component (A) is 0.005 to 20.0 mass %, The content of the component (B) is 0.005 to 10.0 mass %, The content of the component (C) is 0.05 to 20.0 mass %, An oil-in-water emulsion composition, which is a Pickering emulsion having an aqueous phase containing the component (D) and an oil phase containing the component (B). Component (A): Octenyl succinic acid starch ester metal salt Component (B): One or more oily components selected from the group consisting of hydrocarbon oils, fatty acid triglycerides, and vegetable oils Component (C): PEG / PPG / Polybutylene Glycol-8 / 5 / 3 Glycerin Component (D): water

2. The oil-in-water emulsion composition according to claim 1, further comprising a colorant.

3. 3. The oil-in-water emulsion composition according to claim 1, which may or may not contain ethanol, and the ethanol content is 30.0% by mass or less.

Images