Aqueous slurry, emulsion, cosmetic, method for producing aqueous slurry, method for producing water-in-oil emulsion, and method for producing oil-in-water emulsion

Abstract

Provided is an aqueous slurry containing a hydrophobic powder (A), one or more types of a first surfactant (B) selected from quaternary ammonium salts, an alcohol (C), and water (D).

Description

[Technical Field]

[0001] The present invention relates to aqueous slurries, emulsions, cosmetics, methods for producing aqueous slurries, methods for producing water-in-oil emulsions, and methods for producing oil-in-water emulsions. [Background technology]

[0002] Cosmetics such as liquid foundations and sunscreens contain an oil phase, such as an oil-based formulation, and an aqueous phase, such as an aqueous-based formulation. To impart various functions to the cosmetic, such as UV protection, color development, and concealment, metal oxide powders such as UV scattering agents and pigments are dispersed in the oil phase. Furthermore, these powders are subjected to hydrophobic treatment to impart water resistance and longevity to the cosmetic, to sequester the surface catalytic activity of the metal oxides, or to improve the feel of the product (for example, Patent Documents 1 and 2). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-073460 [Patent Document 2] Japanese Patent Publication No. 2015-168635 [Overview of the project] [Problems that the invention aims to solve]

[0004] Because metal oxide powders have a hydrophobic surface treatment, they disperse well in the oil phase but not easily in the aqueous phase, making it difficult to disperse them throughout the entire cosmetic composition. Therefore, conventional cosmetics have limitations in the various functions they can impart, such as UV protection.

[0005] The object of the present invention is to provide an aqueous slurry that can improve the various functions of cosmetics. [Means for solving the problem]

[0006] An aqueous slurry according to one aspect of the present invention is a hydrophobic metal oxide (A) 0.1% by mass or more and 50% by mass or less , one or more first surfactants (B) selected from quaternary ammonium salts 0.01% by mass or more and 10% by mass or less , alcohol (C) 1% by mass or more and 25% by mass or less , and water (D) 20% by mass or more and 99% by mass or less It contains. [Effects of the Invention]

[0007] According to one aspect of the present invention, the various functions of cosmetics can be improved. [Brief explanation of the drawing]

[0008]

Figure 1

Figure 2

Figure 3

[0009] The embodiments of the present invention will be described in detail below.

[0010] <Water-based slurry> The aqueous slurry according to this embodiment contains a hydrophobic powder (A), one or more first surfactants selected from quaternary ammonium salts (B), an alcohol (C), and water (D). In this specification, the aqueous slurry refers to a suspension in which the powder is dispersed in an aqueous medium.

[0011] The hydrophobic powder (A) is not particularly limited, and examples thereof include powders that are hydrophobic by themselves, powders obtained by hydrophobizing the surface of hydrophilic powders, powders obtained by further hydrophobizing the surface of hydrophobic powders, and the like. Here, the hydrophobic powder is a powder that is dispersed in the hexane phase when the powder is dispersed in a mixed solvent having a mass ratio of water to hexane of 1:1.

[0012] Examples of powders that are hydrophobic by themselves include organic resin powders such as polystyrene powder, polyethylene powder, N-acyl lysine powder, epoxy resin powder, (vinyldimethylsilicone / methylsilicone sesquioxane) cross-polymer powder, (diphenyldimethylsilicone / vinyldiphenyldimethylsilicone / silsesquioxane) cross-polymer powder, and metal soap powders such as aluminum stearate, zinc laurate, and magnesium stearate.

[0013] The powder obtained by hydrophobizing the surface of the hydrophilic powder may be a raw material commonly used in cosmetics, and examples thereof include inorganic powders, organic powders, composite powders, and the like.

[0014] Examples of inorganic powders include titanium oxide, black titanium oxide, congo, ultramarine, red iron oxide, yellow iron oxide, black iron oxide, zinc oxide, cerium oxide, aluminum oxide, magnesium oxide, zirconium oxide, magnesium carbonate, calcium carbonate, carbon black, aluminum silicate, magnesium silicate, aluminum magnesium silicate, mica, synthetic mica, synthetic sericite, sericite, talc, silicon carbide, barium sulfate, boron nitride, and the like.

[0015] Examples of organic powders include nylon powder, acrylic powder, silk powder, crystalline cellulose, N-acyl lysine, and tar-based pigments.

[0016] Examples of composite powders include bismuth oxychloride, mica titanium, iron oxide-coated mica, iron oxide mica titanium, organic pigment-treated mica titanium, aluminum powder, and the like. One or more of these powders can be used.

[0017] The treatment agent used for hydrophobizing the powder (hereinafter referred to as hydrophobizing treatment agent) is not particularly limited. For example, silicone compounds such as dimethylpolysiloxane (dimethyl silicone), methylhydrogenpolysiloxane (hydrogen dimethyl silicone), combination of hydrogen dimethyl silicone, high-viscosity silicone, crosslinked silicone, fluorine-modified silicone, acrylic-modified silicone, silicone resin, trichlorosilanes such as octadecyltrichlorosilane, triethoxysilanes such as octyltriethoxysilane (OTS), perfluoroalkylsilane, surfactants such as anionic surfactants, cationic surfactants, nonionic surfactants, metal soaps such as zinc laurate, zinc stearate, higher fatty acids such as polyisobutylene, wax, stearic acid, higher fatty acid esters such as dextrin palmitate, oil agents such as higher alcohols, N-acyl amino acids, perfluoroalkyl phosphoric acid and its salts, perfluoropolyethers, fluorine compounds such as perfluoropolyether alkyl phosphoric acid and its salts, polyvinylpyrrolidone-modified polymers such as copolymers of polyvinylpyrrolidone-hexadecene, etc. These hydrophobizing treatment agents can be used alone or in combination of two or more. Further, these hydrophobizing treatment agents may be used in combination with inorganic surface modifiers such as aluminum hydroxide and silica.

[0018] Also, the method for treating the powder with these hydrophobizing treatment agents is not particularly limited, and examples thereof include a wet method using a solvent, a gas phase method, a mechanochemical method, etc. Further, the treatment amount with the hydrophobizing treatment agent is not particularly limited, but in consideration of adhesion to the skin, uniformity of finish, and makeup retention, it is preferably 0.5 mass% or more and 25 mass% or less, more preferably 2 mass% or more and 15 mass% or less, based on the hydrophobic powder (A).

[0019] The content of hydrophobic powder (A) is not particularly limited, but is preferably 0.1% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 30% by mass or less, and even more preferably 10% by mass or more and 25% by mass or less. When the hydrophobic powder content is within this range, the powder's functionality can be sufficiently imparted, and good dispersibility can also be maintained.

[0020] One or more first surfactants (B) selected from quaternary ammonium salts are, for example, quaternary ammonium salt type cationic surfactants. The quaternary ammonium salt type cationic surfactant used in this embodiment is dialkyldimethylammonium chloride, represented by the following general formula.

[0021] [ka] (In the formula, R1 represents an alkyl group having 10 to 22 carbon atoms or a benzyl group, R2 represents a methyl group or an alkyl group having 10 to 22 carbon atoms, R3 and R4 represent an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group, and X represents a halogen atom or a methyl sulfate residue.)

[0022] Examples of dialkyldimethylammonium chloride represented by the above general formula include distearyldimethylammonium chloride, dihexadecyldimethylammonium chloride, ditetradecyldimethylammonium chloride, didodecyldimethylammonium chloride, and didecyldimethylammonium chloride, among which distearyldimethylammonium chloride is preferred.

[0023] The content of the first surfactant (B) is not particularly limited, but is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 6% by mass or less, and even more preferably 1% by mass or more and 5% by mass or less. When the content of the first surfactant (B) is within this range, good dispersibility of the hydrophobic powder in the aqueous phase can be maintained when the aqueous slurry is dispersed in the aqueous phase.

[0024] Alcohol (C) is not particularly limited and can include lower alcohols, polyhydric alcohols, etc.

[0025] Examples of lower alcohols include ethanol, propanol, isopropanol, isobutyl alcohol, and t-butyl alcohol.

[0026] Examples of polyhydric alcohols include dihydric alcohols (e.g., ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, tetramethylene glycol, 2,3-butylene glycol, pentamethylene glycol, 2-butene-1,4-diol, hexylene glycol, octylene glycol, etc.); trihydric alcohols (e.g., glycerin, trimethylolpropane, etc.); tetrahydric alcohols (e.g., pentaerythritol such as 1,2,6-hexanetriol, etc.); pentahydric alcohols (e.g., xylitol, etc.); hexahydric alcohols (e.g., sorbitol, mannitol, etc.); and polyhydric alcohol polymers (e.g., diethylene glycol, dipropylene glycol, triethylene Ethylene glycol, polypropylene glycol, tetraethylene glycol, diglycerin, polyethylene glycol, triglycerin, tetraglycerin, polyglycerin, etc.); divalent alcohol alkyl ethers (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-methylhexyl ether, ethylene glycol isoamyl ether, ethylene glycol benzyl ether, ethylene glycol isopropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, etc.);Dihydric alcohol alkyl ethers (e.g., diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol butyl ether, diethylene glycol methyl ethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol isopropyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol butyl ether, etc.); Dihydric alcohol ether esters (e.g., ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, ethylene glycol diazibate, ethylene glycol Examples include disuccinates, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monophenyl ether acetate, etc.; glycerin monoalkyl ethers (e.g., xyl alcohol, cerakyl alcohol, batyl alcohol, etc.); sugar alcohols (e.g., sorbitol, maltitol, maltotriose, mannitol, sucrose, erythritol, glucose, fructose, starch-derived sugars, maltose, xylitol, starch-derived sugar-reduced alcohols, etc.); glycerin solids; tetrahydrofurfuryl alcohol; POE-tetrahydrofurfuryl alcohol; POP-butyl ether; POP·POE-butyl ether; tripolyoxypropylene glycerin ether; POP-glycerin ether; POP-glycerin ether phosphate; POP·POE-pentaneerythritol ether, polyglycerin, etc.

[0027] The alcohol (C) content is not particularly limited, but is preferably 1% by mass or more and 25% by mass or less, more preferably 2.5% by mass or more and 15% by mass or less, and even more preferably 5% by mass or more and 15% by mass or less. When the alcohol (C) content is within this range, the dispersibility of hydrophobic powders in aqueous slurry can be stabilized.

[0028] Water (D) constitutes the medium for the hydrophobic powder in the aqueous slurry. Water (D) is the residue remaining in the aqueous slurry after removing the hydrophobic powder (A), the first surfactant (B), the alcohol (C), and other optional components.

[0029] The water (D) content is not particularly limited, but is preferably 20% by mass or more and 99% by mass or less, more preferably 55% by mass or more and 95% by mass or less, and even more preferably 60% by mass or more and 80% by mass or less. When the water (D) content is within this range, the suspension state of the aqueous slurry can be stabilized.

[0030] As described above, the aqueous slurry of this embodiment contains a hydrophobic powder (A), one or more first surfactants (B) selected from quaternary ammonium salts, an alcohol (C), and water (D). By mixing this aqueous slurry with the aqueous phase of a cosmetic composition having an oil phase and an aqueous phase, the hydrophobic powder can be dispersed not only in the oil phase but also in the aqueous phase. Therefore, the slurry of this embodiment can improve various functions of the cosmetic composition, such as UV protection, color development, and opacity.

[0031] Furthermore, in the aqueous slurry of this embodiment, by selecting the first surfactant (B) from dialkyldimethylammonium chloride represented by the above general formula, the dispersibility of hydrophobic powders in the aqueous phase when the aqueous slurry is dispersed in the aqueous phase can be improved.

[0032] Furthermore, in the aqueous slurry of this embodiment, the suspension state of the aqueous slurry can be stabilized by having alcohol (C) be at least one selected from lower alcohols and polyhydric alcohols.

[0033] The form of the aqueous slurry according to this embodiment is not particularly limited, but it is preferably an aqueous slurry in which hydrophobic powder (A) is dispersed in a solvent containing a first surfactant (B), an alcohol (C), and water (D). Here, the solvent refers to a mixed solvent of the first surfactant (B), an alcohol (C), and water (D).

[0034] In this embodiment, by dispersing the hydrophobic powder (A) in such a mixed solvent, dispersion of the hydrophobic powder (A) in the aqueous slurry becomes possible, and the suspension state of the aqueous slurry can be further stabilized. Furthermore, by stabilizing the suspension state of the aqueous slurry, the dispersibility of the hydrophobic powder in the aqueous phase when the aqueous slurry is dispersed in the aqueous phase can be further improved.

[0035] Furthermore, a more preferable embodiment of the aqueous slurry according to this embodiment is an aqueous slurry in which a mixture of hydrophobic powder (A), a first surfactant (B), and alcohol (C) is dispersed in water (D). Here, the mixture refers to a state in which the hydrophobic powder (A) is impregnated with the first surfactant (B) and alcohol (C).

[0036] In this embodiment, dispersing such a mixture in water further improves the dispersibility of the hydrophobic powder (A) in the aqueous slurry and further stabilizes the suspension state of the aqueous slurry. Furthermore, by stabilizing the suspension state of the aqueous slurry, the dispersibility of the hydrophobic powder in the aqueous phase when the aqueous slurry is dispersed in the aqueous phase can be further improved.

[0037] In the aqueous slurry according to this embodiment, if the content of a quaternary ammonium salt type cationic surfactant such as distearyldimethylammonium chloride as the first surfactant (B) is high, the odor of the aqueous slurry may deteriorate. Therefore, it is preferable that the aqueous slurry of this embodiment further contains a second surfactant (E).

[0038] The second surfactant (E) is one or more nonionic surfactants (also called nonionic surfactants) with an HLB of 10 or more. The content of the second surfactant (E) is not particularly limited, but is preferably 0.01% by mass or more and 6% by mass or less, more preferably 0.3% by mass or more and 4% by mass or less, and even more preferably 0.5% by mass or more and 3% by mass or less.

[0039] Examples of the above-mentioned nonionic surfactants include polyoxyethylene glycol alkyl esters, polyoxyethylene glyceryl alkyl esters, polyoxyethylene hydrogenated castor oil, polyalkylene glycol phytosterol ethers, polyethylene glycol alkyl ethers, polyglycerin alkyl esters, polyoxyethylene sorbitan fatty acid esters, polyglycerin alkyl esters, and polyether-modified silicones.

[0040] In the aqueous slurry of this embodiment, by incorporating such a second surfactant (E), the suspension state of the aqueous slurry can be stabilized even if the content of the first surfactant (B) is reduced. Furthermore, in the aqueous slurry of this embodiment, since the content of the first surfactant (B) can be reduced, the odor of the aqueous slurry can be stabilized. Moreover, by stabilizing the suspension state of the aqueous slurry, the dispersibility of hydrophobic powders in the aqueous phase when the aqueous slurry is dispersed in the aqueous phase can be improved.

[0041] Furthermore, in the aqueous slurry according to this embodiment, if the content of a quaternary ammonium salt type cationic surfactant such as distearyldimethylammonium chloride is high as the first surfactant (B), the aqueous slurry may aggregate and the suspension state may become unstable when an aqueous thickener such as an anionic polymer is added. Therefore, it is preferable that the aqueous slurry of this embodiment further contains a third surfactant (F).

[0042] The third surfactant (F) is one or more selected from anionic surfactants. The content of the third surfactant (F) is not particularly limited, but is preferably 0.01% by mass or more and 3% by mass or less, more preferably 0.2% by mass or more and 2% by mass or less, and even more preferably 0.3% by mass or more and 1% by mass or less.

[0043] Examples of anionic surfactants include alkylmethyl taurate salts such as sodium stearoylmethyl taurate; alkyl glutamate salts such as sodium stearoyl glutamate; potassium neutralized salts and sodium neutralized salts of higher fatty acids having 12 to 22 carbon atoms; and triethanolamine neutralized salts.

[0044] In the aqueous slurry according to this embodiment, by incorporating such a third surfactant (F), it is possible to maintain a stable suspension state of the aqueous slurry and improve the dispersibility of hydrophobic powders when the aqueous slurry is dispersed in the aqueous phase. Furthermore, by incorporating the third surfactant (F), even if the first surfactant (B) is present, aggregation will not occur when an aqueous thickener such as an anionic polymer is added, and a uniform aqueous slurry can be maintained.

[0045] The aqueous slurry of this embodiment may contain other components besides the above-mentioned components, such as colorants (excluding the hydrophobic powder), stabilizers, surfactants (excluding the surfactant), antioxidants, and preservatives, to the extent that it does not impair the effects of the present invention.

[0046] Colorants are components that color aqueous slurries (color cosmetics). Examples of colorants include inorganic white pigments such as red iron oxide, yellow iron oxide, black iron oxide, and zinc oxide; inorganic red pigments such as iron titanate; inorganic purple pigments such as mango violet and cobalt violet; inorganic green pigments such as chromium oxide, chromium hydroxide, and cobalt titanate; inorganic blue pigments such as ultramarine and Prussian blue; metal powder pigments such as aluminum powder and copper powder; organic pigments such as zirconium, barium, or aluminum lake; and natural pigments such as chlorophyll and β-carotene. These colorants may be used individually or in mixtures of two or more types.

[0047] The colorant content is not particularly limited, but is 0.1% by mass or more and 20% by mass or less in the aqueous slurry, preferably 0.3% by mass or more and 15% by mass or less, and more preferably 0.5% by mass or more and 10% by mass or less.

[0048] Stabilizers are components that impart viscosity or adhesiveness to an aqueous slurry, thereby maintaining its shape. Examples of stabilizers include dextrin fatty acid esters, sucrose fatty acid esters, cellulose derivatives, aluminum isostearate, dibutylethylhexanoyl glutamide, dibutyllauroyl glutamide, bis-dialkyl(C14-18)amide (ethylenediamine / hydrogenated dimer dilinoleic acid) copolymer, and (VP / eicosene) copolymer. These stabilizers can be used individually or in combination of two or more.

[0049] Examples of surfactants include amphoteric surfactants, cationic surfactants, anionic surfactants, and nonionic surfactants, as shown below.

[0050] Amphoteric surfactants have at least one cationic functional group and one anionic functional group. They are cationic when the solution is acidic and anionic when it is alkaline, and near their isoelectric point they have properties similar to nonionic surfactants.

[0051] Amphoteric surfactants are classified into carboxylic acid type, sulfate ester type, sulfonic acid type, and phosphate ester type depending on the type of anionic group. In this embodiment, among these, the carboxylic acid type, sulfate ester type, and sulfonic acid type are preferred. The carboxylic acid type is further classified into amino acid type and betaine type. In this embodiment, among these, the betaine type is preferred.

[0052] Specific examples of amphoteric surfactants include imidazoline-based amphoteric surfactants (e.g., 2-undecyl-N,N,N-(hydroxyethylcarboxymethyl)-2-imidazoline sodium, 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt, etc.) and betaine-based surfactants (e.g., 2-heptadecyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, lauryldimethylaminoacetic acid betaine, alkyl betaine, amide betaine, sulfobetaine, etc.).

[0053] Examples of cationic surfactants include quaternary ammonium salts such as cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, behenyltrimethylammonium chloride, behenyldimethylhydroxyethylammonium chloride, stearyldimethylbenzylammonium chloride, and cetyltriethylammonium methyl sulfate. Other examples include amideamine compounds such as diethylaminoethylamide stearate, dimethylaminoethylamide stearate, diethylaminoethylamide palmitate, dimethylaminoethylamide palmitate, diethylaminoethylamide myristate, dimethylaminoethylamide myristate, diethylaminoethylamide behenate, dimethylaminoethylamide behenate, diethylaminopropylamide stearate, dimethylaminopropylamide stearate, diethylaminopropylamide palmitate, dimethylaminopropylamide palmitate, diethylaminopropylamide myristate, dimethylaminopropylamide myristate, diethylaminopropylamide behenate, and dimethylaminopropylamide behenate.

[0054] Anionic surfactants are classified into, for example, carboxylate types such as fatty acid soaps, N-acyl glutamates, and alkyl ether acetates; sulfonic acid types such as α-olefin sulfons, alkanesulfons, and alkylbenzenesulfonic acids; sulfate ester types such as higher alcohol sulfate esters; and phosphate ester types.

[0055] Examples of anionic surfactants include fatty acid soaps (e.g., sodium laurate, sodium palmitate, etc.), higher alkyl sulfate salts (e.g., sodium lauryl sulfate, potassium lauryl sulfate, etc.), alkyl ether sulfate salts (e.g., POE-triethanolamine lauryl sulfate, POE-sodium lauryl sulfate, etc.), N-acyl sarcosinate (e.g., sodium lauroyl sarcosinate, etc.), higher fatty acid amide sulfonates (e.g., sodium N-myristoyl-N-methyltaurate, sodium coconut oil fatty acid methyl taulide, sodium lauryl methyl taulide, etc.), phosphate salts (e.g., sodium POE-oleyl ether phosphate, POE-stearyl ether phosphate, etc.), sulfosuccinates (e.g., sodium di-2-ethylhexyl sulfosuccinate, sodium monolauroyl monoethanolamide polyoxyethylene sulfosuccinate, lauryl polypropylene glycol sulfosuccinate) Examples include sodium citrate, alkylbenzene sulfonates (e.g., linear dodecylbenzenesulfonate sodium, linear dodecylbenzenesulfonate triethanolamine, linear dodecylbenzenesulfonate, etc.), higher fatty acid ester sulfates (e.g., hydrogenated coconut oil fatty acid glycerin sulfate sodium, etc.), N-acyl glutamates (e.g., N-lauroyl glutamate monosodium, N-stearoyl glutamate disodium, N-myristoyl-L-glutamate monosodium, etc.), sulfated oils (e.g., belladonna oil, etc.), POE-alkyl ether carboxylic acids, POE-alkyl allyl ether carboxylic acid salts, α-olefin sulfonates, higher fatty acid ester sulfonates, secondary alcohol sulfates, higher fatty acid alkylolamide sulfates, lauroyl monoethanolamide succinate sodium, N-palmitoyl aspartate ditriethanolamine, sodium caseinate, etc.

[0056] Nonionic surfactants are surfactants that do not ionize and acquire an electric charge in aqueous solution. Nonionic surfactants include hydrophobic nonionic surfactants and hydrophilic nonionic surfactants.

[0057] Known hydrophobic nonionic surfactants include types using alkyl groups as hydrophobic groups and types using dimethyl silicone.

[0058] Specific examples of types using alkyl as the hydrophobic group include glycerin fatty acid esters, ethylene oxide derivatives of glycerin fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, ethylene oxide derivatives of propylene glycol fatty acid esters, polyethylene glycol fatty acid esters, polyethylene glycol alkyl ethers, polyethylene glycol alkylphenyl ethers, polyethylene glycol castor oil derivatives, and polyethylene glycol hydrogenated castor oil derivatives.

[0059] Furthermore, specific examples of types using dimethyl silicone as the hydrophobic group include polyether-modified silicone and polyglycerin-modified silicone.

[0060] Among these, hydrophobic nonionic surfactants are preferred if they use alkyl as the hydrophobic group.

[0061] Examples of hydrophilic nonionic surfactants include POE-sorbitan fatty acid esters (e.g., POE-sorbitan monooleate, POE-sorbitan monostearate, POE-sorbitan monooleate, POE-sorbitan tetraoleate, etc.), POE-sorbitol fatty acid esters (e.g., POE-sorbitol monolaurate, POE-sorbitol monooleate, POE-sorbitol pentaoleate, POE-sorbitol monostearate, etc.), and POE-glycerin fatty acid esters (e.g., POE-glycerin monostearate). POE-monoleates such as POE-glycerin monoisostearate and POE-glycerin triisostearate), POE-fatty acid esters (e.g., POE-distearate, POE-monodiolate, ethylene glycol distearate), POE-alkyl ethers (e.g., POE-lauryl ether, POE-oleyl ether, POE-stearyl ether, POE-behenyl ether, POE-2-octyldodecyl ether, POE-cholestanol ether), poloxamer types (e.g., Pluronic (registered trademark) POE·POP-alkyl ethers (e.g., POE·POP-cetyl ether, POE·POP-2-decyltetradecyl ether, POE·POP-monobutyl ether, POE·POP-hydrogenated lanolin, POE·POP-glycerin ether, etc.), tetra-POE·tetraPOP-ethylenediamine condensates (e.g., Tetronic®, etc.), POE-castor oil hydrogenated castor oil derivatives (e.g., POE-castor oil, POE-hydrogenated castor oil, POE-hydrogenated castor oil monoisostearate, POE-hydrogenated castor oil triisostearate) Examples include POE-hydrogenated castor oil monopyloglutamic acid monoisostearate diester, POE-hydrogenated castor oil maleic acid, etc., POE-beeswax / lanolin derivatives (e.g., POE-sorbitol beeswax, etc.), alkanolamides (e.g., coconut oil fatty acid diethanolamide, lauric acid monoethanolamide, fatty acid isopropanolamide, etc.), POE-propylene glycol fatty acid ester, POE-alkylamine, POE-fatty acid amide, sucrose fatty acid ester, alkylethoxydimethylamine oxide-trioleyl phosphate, etc.

[0062] The amount of activator is not particularly limited, but is 0.01% by mass or more and 20% by mass or less in the aqueous slurry, preferably 0.1% by mass or more and 10% by mass or less, and more preferably 0.5% by mass or more and 5% by mass or less.

[0063] Examples of antioxidants include ascorbic acid, α-tocopherol, dibutylhydroxytoluene, and butylhydroxyanisole.

[0064] Examples of preservatives include parahydroxybenzoic acid esters, phenoxyethanol, octoxyglycerin, benzoic acid, salicylic acid, carbolic acid, sorbic acid, parachlormethacresol, hexachlorophene, benzalkonium chloride, chlorhexidine chloride, and trichlorocarbanilide.

[0065] <Method for producing aqueous slurry> Figure 1 is a flowchart showing an example of a method for producing an aqueous slurry according to this embodiment. The method for producing an aqueous slurry according to this embodiment includes the steps of heating and dissolving a hydrophobic powder (A), a quaternary ammonium salt type surfactant (B), and an alcohol (C) at 80°C to 90°C to obtain a mixture, and dispersing the mixture in water (D) (Figure 1, steps S1 to S2).

[0066] Specifically, a quaternary ammonium salt surfactant (B) and alcohol (C) are placed in a container such as a disperser mixer, heated and dissolved at 85°C, and a hydrophobic powder (A) is added while stirring to prepare a mixture (Figure 1, Step S1). Furthermore, water (D) is added to this mixture and stirred in a homogenizer at 7000 rpm for 2 minutes to disperse and obtain an aqueous slurry (Figure 1, Step S2). The stirring time is arbitrary, for example, from 1 to 20 minutes.

[0067] In the method for producing an aqueous slurry according to this embodiment, a mixture obtained by heating and dissolving a hydrophobic powder (A), a quaternary ammonium salt type surfactant (B), and an alcohol (C) at 80°C to 90°C is dispersed in water (D).

[0068] This improves the dispersibility of the hydrophobic powder (A) in the aqueous slurry, and further stabilizes the suspension state of the aqueous slurry. Furthermore, by stabilizing the suspension state of the aqueous slurry, the dispersibility of the hydrophobic powder in the aqueous phase can be further improved by dispersing the resulting aqueous slurry in the aqueous phase.

[0069] <Emulsion> The emulsion according to this embodiment is an emulsion containing the aqueous slurry described above. The form of the emulsion in this embodiment is arbitrary and includes water-in-oil emulsions and oil-in-water emulsions. A water-in-oil emulsion is an emulsion in which the continuous phase (outer phase) is an oil phase and the dispersed layer (inner phase) is an aqueous phase. An oil-in-water emulsion is an emulsion in which the continuous phase (outer phase) is an aqueous phase and the dispersed layer (inner phase) is an oil phase.

[0070] In the emulsion of this embodiment, the composition of the oil phase is arbitrary and, for example, consists of oily components (oils). Examples of oily components (oils) include volatile oils, non-volatile oils, and oil-soluble ultraviolet absorbers.

[0071] Volatile oils are oily components that evaporate at room temperature. Examples of volatile oils include hydrocarbon oils such as isododecane and isohexadecane; linear silicone oils such as dimethylpolysiloxane (dimethicone), methylphenylpolysiloxane, and methylhydrogenpolysiloxane; and cyclic silicone oils such as cyclopentasiloxane. These volatile oils can be used individually or in combination of two or more types.

[0072] Non-volatile oils are oily components that do not evaporate at room temperature. Examples of non-volatile oils include paraffin, liquid paraffin, ozokerite, squalane, squalene, pristane, ceresin, petrolatum, glyceryl tri-2-ethylhexanoate, isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, octyl palmitate, octyl isopalmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, Cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isopropyl isostearate, isocetyl isostearate, cholesteryl 12-hydroxystearylate, ethylene glycol di-2-ethylhexylate, dipentaerythritol fatty acid ester, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, glyceryl di-2-heptylundecanoate, trimethylol tri-2-ethylhexylate Trimethylolpropane, trimethylolpropane triisostearate, pentaneerythritol tetra-2-ethylhexylate, glycerin tri-2-ethylhexylate, trimethylolpropane triisostearate, cetyl-2-ethylhexanoate, 2-ethylhexyl palmitate, glycerin trimyristate, glyceride tri-2-heptylundecanoate, methyl castor oil fatty acid ester, oleic acid oil, acetoglyceride, 2-heptylundecanoate Cyl, diisobutyl adipate, 2-cutyldodecyl N-lauroyl-L-glutamate, di-2-heptylundecyl adipate, ethyl laurate, diethyl sebacate, diisopropyl sebacate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, 2-ethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, triethyl citrate, crotamiton (C 13 H 17 Examples include NO). These non-volatile liquid oils can be used individually or in combination of two or more types.

[0073] Examples of oil-soluble UV absorbers include benzoic acid-based UV absorbers (e.g., para-aminobenzoic acid (hereinafter abbreviated as PABA), PABA monoglycerol ester, N,N-dipropoxy PABA ethyl ester, N,N-diethoxy PABA ethyl ester, N,N-dimethyl PABA ethyl ester, N,N-dimethyl PABA butyl ester, N,N-dimethyl PABA ethyl ester, etc.), anthranilic acid-based UV absorbers (e.g., homomenthyl-N-acetylantranilate, etc.), and salicylic acid-based UV absorbers (e.g., amyl salicylate). (e.g., menthyl salicylate, homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, p-isopropanolphenyl salicylate, etc.), cinnamic acid-based UV absorbers (e.g., octyl cinnamate, ethyl-4-isopropyl cinnamate, methyl-2,5-diisopropyl cinnamate, ethyl-2,4-diisopropyl cinnamate, methyl-2,4-diisopropyl cinnamate, propyl-p-methoxy cinnamate, isopropyl-p-methoxy cinnamate, isoamyl-p-methoxy cinnamate) Cinnamate, octyl-p-methoxycinnamate (2-ethylhexyl-p-methoxycinnamate), 2-ethoxyethyl-p-methoxycinnamate, cyclohexyl-p-methoxycinnamate, ethyl-α-cyano-β-phenyl cinnamate, 2-ethylhexyl-α-cyano-β-phenyl cinnamate, glyceryl mono-2-ethylhexanoyl-diparamethoxycinnamate, etc., benzophenone-based UV absorbers (e.g., 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2 ,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 4-phenylbenzophenone, 2-ethylhexyl-4'-phenylbenzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone, etc.), 3-(4'-methylbenzylidene)-d,l-camphor, 3-benzylidene-d,Examples include l-camphor, 2-phenyl-5-methylbenzoxazole, 2,2'-hydroxy-5-methylphenylbenzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, dibenzarazine, dianisioylmethane, 4-methoxy-4'-t-butyldibenzoylmethane, 5-(3,3-dimethyl-2-norbornylidene)-3-pentan-2-one, etc.

[0074] The content of oily components in the oil phase of the emulsion is not particularly limited, but is 5% by mass or more and 95% by mass or less in the emulsion, preferably 10% by mass or more and 90% by mass or less, and more preferably 15% by mass or more and 85% by mass or less. When the content of oily components is within this range, the usability of the cosmetic when used in a cosmetic composition is not likely to decrease.

[0075] The oil phase of the emulsion may contain other components besides those mentioned above, such as colorants, stabilizers, surfactants (excluding the surfactants mentioned above), antioxidants, and preservatives, to the extent that it does not impair the effects of the present invention. These stabilizers may be the same as the other components optionally included in the aqueous slurry described above.

[0076] In the emulsion of this embodiment, the composition of the aqueous phase is arbitrary and may consist of, for example, the aqueous slurry described above, or it may consist of an aqueous component that includes the aqueous slurry described above.

[0077] Water-based components are those that dissolve easily in water. Examples of water-based components include water, lower alcohols such as ethanol, and polyhydric alcohols such as glycerin. These water-based components may be used individually or in mixtures of two or more.

[0078] The content of the aqueous component is not particularly limited, but is 0.1% by mass or more and 30% by mass or less in the emulsion, preferably 0.5% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 15% by mass or less. When the content of the aqueous component is within this range, the usability of the cosmetic composition does not tend to decrease when the emulsion containing the aqueous component is used in the cosmetic composition.

[0079] In this embodiment, when the emulsion is a water-in-oil emulsion, the dispersed phase of the emulsion contains the aqueous slurry described above. Specifically, the aqueous slurry is included in the internal phase (aqueous phase) of the water-in-oil (W / O) emulsion, so that the hydrophobic powder is dispersed in the internal phase (aqueous phase) of the water-in-oil (W / O) emulsion.

[0080] In the emulsion according to this embodiment, the inclusion of an aqueous slurry in the dispersed phase of the emulsion allows the hydrophobic powder to be dispersed not only in the outer phase (oil phase) of the water-in-oil emulsion but also in the inner phase (aqueous phase or inner aqueous phase). Therefore, it becomes possible to disperse the hydrophobic powder throughout the entire emulsion. Furthermore, cosmetics using such an emulsion can improve various functions such as UV protection, color development, and opacity.

[0081] In this embodiment, when the emulsion is an oil-in-water emulsion, the aqueous slurry described above is included in the continuous phase of the emulsion. Specifically, the aqueous slurry is included in the outer phase (aqueous phase or outer aqueous phase) of the oil-in-water (O / W) emulsion, so that the hydrophobic powder is dispersed in the outer phase (aqueous phase or outer aqueous phase) of the oil-in-water (O / W) emulsion.

[0082] In the emulsion according to this embodiment, the inclusion of an aqueous slurry in the continuous phase of the emulsion allows the hydrophobic powder to be dispersed not only in the internal phase (oil phase) of the oil-in-water emulsion but also in the external phase (aqueous phase). Therefore, it becomes possible to disperse the hydrophobic powder throughout the entire emulsion. Furthermore, cosmetics using such an emulsion can improve various functions such as UV protection, color development, and opacity.

[0083] <Method for manufacturing emulsion>

[0084] Figures 2 and 3 are flowcharts illustrating an example of a method for producing an emulsion according to this embodiment. Figure 2 shows an example of a method for producing a water-in-oil emulsion according to this embodiment, and Figure 3 shows an example of a method for producing an oil-in-water emulsion according to this embodiment.

[0085] In the method for producing a water-in-oil emulsion according to this embodiment, a water-in-oil (W / O) emulsion is obtained by dispersing an aqueous component containing the aforementioned aqueous slurry in an oily component (Figure 2, step S11). Specifically, a mixture is prepared by pre-mixing the oil phase components by stirring, and the aforementioned aqueous slurry is gradually added to this mixture as the aqueous component while stirring. Then, the mixture is emulsified by stirring at 7000 rpm for 2 minutes using a homogenizer. This disperses the aqueous slurry in the dispersed phase (aqueous phase) to obtain a water-in-oil (W / O) emulsion.

[0086] In the method for producing a water-in-oil emulsion according to this embodiment, as described above, an aqueous slurry with high dispersibility of hydrophobic powder (A) and a stable suspension state is dispersed in the aqueous phase (internal phase or internal aqueous phase) of a water-in-oil (W / O) emulsion. As a result, a water-in-oil (W / O) emulsion with improved dispersibility of hydrophobic powder in the aqueous phase (internal phase or internal aqueous phase) can be obtained.

[0087] In the method for producing an oil-in-water emulsion according to this embodiment, an oil-in-water (O / W) emulsion is obtained by dispersing an oily component in an aqueous component containing the aqueous slurry described above (Figure 3, step S21). Specifically, the aqueous slurry described above is prepared as the aqueous component, and a mixture prepared by pre-mixing the oil phase component is gradually added to this aqueous component while stirring, and then the mixture is emulsified by stirring at 7000 rpm for 2 minutes with a homogenizer. This disperses the aqueous slurry in a continuous phase (aqueous phase) to obtain an oil-in-water (O / W) emulsion.

[0088] In the method for producing an oil-in-water emulsion according to this embodiment, as described above, an aqueous slurry with high dispersibility of hydrophobic powder (A) and a stable suspension state is dispersed in the aqueous phase (outer phase or outer aqueous phase) of the oil-in-water (O / W) emulsion. As a result, an oil-in-water (O / W) emulsion with improved dispersibility of hydrophobic powder in the aqueous phase (outer phase or outer aqueous phase) can be obtained.

[0089] <Cosmetics> The cosmetic composition according to this embodiment contains the emulsion described above. That is, the cosmetic composition of this embodiment contains the aqueous slurry described above. Specifically, the cosmetic composition of this embodiment contains the water-in-oil (W / O) emulsion shown in Figure 2, or the oil-in-water (O / W) emulsion shown in Figure 3.

[0090] The form of the cosmetic composition according to this embodiment is not particularly limited and can be in the form of a liquid, emulsion, paste, cream, gel, or the like.

[0091] The uses of the cosmetic composition according to this embodiment are not particularly limited, and can be used for purposes such as makeup base, liquid foundation, cream foundation, concealer, blush, eyeshadow, mascara, eyeliner, eyebrow products, overcoat agents, lipstick, and other makeup cosmetics; UV protection cosmetics such as sunscreen lotion and sunscreen cream; and skincare cosmetics such as skincare lotion, skincare cream, BB cream, and serum. Among these, makeup cosmetics and UV protection cosmetics are preferred, and liquid foundation and sunscreen lotion are more preferred.

[0092] The method for producing the cosmetic composition according to this embodiment is not particularly limited. For example, an aqueous slurry or emulsion (water-in-oil emulsion and oil-in-water emulsion) produced as described above may have other components (colorants, stabilizers, surfactants, antioxidants, preservatives, etc.) added to it, and this mixture may be placed in any cosmetic container from which an appropriate amount of the cosmetic composition can be dispensed.

[0093] As described above, the cosmetic composition according to this embodiment contains a water-in-oil (W / O) emulsion or an oil-in-water (O / W) emulsion in which a water slurry is contained in the aqueous phase (internal phase or internal aqueous phase) and hydrophobic powders are dispersed.

[0094] This makes it possible to incorporate a water-in-oil (W / O) emulsion in the cosmetic composition, in which the aqueous slurry (hydrophobic powder) is dispersed not only in the outer phase (oil phase) but also in the inner phase (aqueous phase), and also to incorporate an oil-in-water (O / W) emulsion in the cosmetic composition, in which the aqueous slurry (hydrophobic powder) is dispersed not only in the inner phase (oil phase) but also in the outer phase (aqueous phase). Therefore, the cosmetic composition of this embodiment can improve various functions such as UV protection, color development, and concealment. [Examples]

[0095] The present invention will be further described below with reference to examples. In the following, "parts" and "%" refer to mass unless otherwise specified. Furthermore, various tests and evaluations will be conducted according to the methods described below.

[0096] <Sample (aqueous slurry)> In a stainless steel container, distearyldimethylammonium chloride (Sanyo Chemical Industries, Ltd., cation DSV) as the first surfactant (B) and dipropylene glycol (Asahi Glass Co., Ltd., DPG-FC) as the alcohol (C) were injected and heated to approximately 85°C until dissolved. Further, a hydrophobic metal oxide was added as a hydrophobic powder (A) while stirring with a disper mixer (PRIMIX, HOMOGENIZING DISPER MODEL 2.5) to prepare a mixture. Deionized water (D) was added to this mixture and stirred with a homogenizer (PRIMIX, TKHOMOMIXER MARK2 MODEL 2.5) at 7000 rpm for 2 minutes to disperse and obtain an aqueous slurry sample.

[0097] <Dispersibility> The appearance of the sample (aqueous slurry) and flow curve measurement (rheological evaluation measuring viscosity as a variable of shear rate) are performed, and the dispersibility of the sample (aqueous slurry) is evaluated according to the following criteria. A: The sample is uniform and no shear thinning is confirmed. B: The sample is uniform, but shear thinning is confirmed by flow curve measurement. C: Aggregation of the powder is visually confirmed and the sample is non-uniform.

[0098] In the above criteria for dispersibility, shear thinning is determined by calculating the viscosity decay rate from the following formula using the viscosity values η(100 s -1 and η(1000 s -1 ) at shear rates of 100 s -1 and 1000 s -1 . A state where the viscosity decay rate is 0.3 or more is regarded as having confirmed shear thinning. Viscosity decay rate = {η(100 s -1 ) - η(1000 s -1 )} / η(100 s -1 )

[0099] <Water resistance> A certain amount (2 mg / cm 2 ) of the sample (aqueous slurry) is applied to a 50 mm square acrylic resin pseudo-substrate that mimics human skin texture, and uniformly applied onto the substrate at a certain load (100 ± 30 g) and a certain speed (100 mm / second × 50 reciprocations). After drying for a certain time (15 minutes), ultraviolet and visible light from 280 to 500 nm is transmitted through the coated substrate using a spectrophotometer (manufactured by Hitachi, Ltd., SPECTROPHOTOMETER U-3500), and the absorbance is calculated from the transmittance measurement. Furthermore, the coated substrate is immersed in a water stream by propeller stirring for 30 minutes, and after drying, the transmittance is measured again by the above method. The ratio of the integrated absorbance at 280 to 340 nm before and after the immersion test in water is defined as the water resistance rate and evaluated according to the following criteria. A: Water resistance rate 80% or more B: Water resistance rate more than 30% and less than 80% C: Water resistance rate less than 30%

[0100] <Odor stability> The odor stability of the sample (aqueous slurry) will be evaluated according to the following criteria. After storing the prepared sample in constant temperature baths at 50°C and 0°C for 4 weeks, a specialist panel will evaluate the odor of the samples stored at 0°C and 50°C according to the following criteria. A: There was no difference in the odor of the samples stored at 0°C and 50°C, and no ammonium odor was detected. Compared to the sample stored at 0°C, a slight ammonium odor was detected in the sample stored at 50°C. A distinct ammonium odor was detected in the sample stored at 50°C.

[0101] <Agglomeration with polymers> The aggregation properties of the sample (aqueous slurry) after the addition of a water-soluble polymer will be evaluated as follows. The prepared sample will be applied to a blackboard using a 10 μm doctor blade, and its appearance will be evaluated according to the following criteria. A: The sample is uniform, and no aggregates or uneven coating are observed. B: The sample is homogeneous, but slight aggregates are observed. C: The sample is non-uniform, the coating is uneven, and numerous aggregates are observed.

[0102] Examples and comparative examples will be described below.

[0103] [Example 1] A sample (aqueous slurry) was prepared and evaluated by blending 2 parts distearyldimethylammonium chloride as the first surfactant (B), 10 parts dipropylene glycol as the alcohol, 20 parts octadecyltrichlorosilane (OTS) / aluminum hydroxide-treated pigment-grade titanium dioxide (manufactured by Daito Chemical Industries, Ltd., OTS-2 TiO2 CR-50) as the hydrophobic powder, and 68 parts ion-exchanged water. The blend and evaluation are shown in Table 1.

[0104] [Example 2] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of OTS-treated zinc oxide (Teika Co., Ltd., MSX-508OTS) were added instead of OTS / aluminum hydroxide-treated titanium oxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0105] [Example 3] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of dimethicone / hydrogen dimethicone treated zinc oxide (Teika Corporation, MZY-510M3S) were added as the hydrophobic powder instead of OTS / aluminum hydroxide treated titanium oxide. The formulation and evaluation are shown in Table 1.

[0106] [Example 4] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of hydrogen dimethicone-treated zinc oxide (Teika Corporation, MZY-203S) were added instead of OTS / aluminum hydroxide-treated titanium oxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0107] [Example 5] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of dextrin palmitate-treated zinc oxide (Teika Co., Ltd., WSX-MZ500) were added instead of OTS / aluminum hydroxide-treated titanium dioxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0108] [Example 6] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of stearic acid / aluminum hydroxide-treated titanium dioxide (manufactured by Titanium Industries Co., Ltd., ST-485SA15) were added instead of OTS / aluminum hydroxide-treated titanium dioxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0109] [Example 7] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of hydrogen dimethicone / aluminum hydroxide-treated titanium dioxide (Sakai Kogyo Co., Ltd., STR-100C-LP) were added instead of OTS / aluminum hydroxide-treated titanium dioxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0110] [Example 8] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 1, except that 20 parts of dimethicone / hydrated silica-treated zinc oxide (Sakai Kogyo Co., Ltd., FINEX-51W-LP3) were added instead of OTS / aluminum hydroxide-treated titanium oxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0111] [Comparative Example 1] The sample was prepared and evaluated in the same manner as in Example 2, except that dipropylene glycol was not included and the amount of deionized water was set to 78 parts. The formulation and evaluation are shown in Table 1.

[0112] [Comparative Example 2] The sample was prepared and evaluated in the same manner as in Example 2, except that distearyldimethylammonium chloride was not included and the amount of deionized water was set to 70 parts. The formulation and evaluation are shown in Table 1.

[0113] [Comparative Example 3] The sample was prepared and evaluated in the same manner as in Comparative Example 2, except that 20 parts of non-hydrophobic modified titanium oxide (aluminum hydroxide treated titanium oxide) were added instead of OTS-treated zinc oxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0114] [Comparative Example 4] The sample was prepared and evaluated in the same manner as in Comparative Example 2, except that 20 parts of non-hydrophobic modified zinc oxide (silica-treated zinc oxide) were added instead of OTS-treated zinc oxide as the hydrophobic powder. The formulation and evaluation are shown in Table 1.

[0115] [Comparative Example 5] The sample was prepared and evaluated in the same manner as in Example 2, except that 2 parts of glyceryl stearate (manufactured by Taiyo Kagaku Co., Ltd., Sunsoft® No. 8004-C) were added instead of distearyldimethylammonium chloride as the first surfactant. The formulation and evaluation are shown in Table 1.

[0116] [Comparative Example 6] The sample was prepared and evaluated in the same manner as in Example 2, except that 2 parts of polypropylene glycol (PPG)-7 / polyethylene glycol (PEG)-30 phytosterol (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® EPP730, HLB:13) were added instead of distearyldimethylammonium chloride as the first surfactant. The formulation and evaluation are shown in Table 1.

[0117] [Example 9] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 2, except that 0.2 parts of polypropylene glycol (PPG)-7 / polyethylene glycol (PEG)-30 phytosterol (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® EPP730, HLB:13) was further added as the second surfactant (E), and the amount of distearyldimethylammonium chloride was increased to 1.8 parts. The formulation and evaluation are shown in Table 2.

[0118] [Example 10] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 2, except that the amount of distearyldimethylammonium chloride was 1.6 parts and the amount of PPG-7 / PEG-30 phytosterol was 0.4 parts. The formulation and evaluation are shown in Table 2.

[0119] [Example 11] A sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 2, except that the amount of distearyldimethylammonium chloride was 1 part and the amount of PPG-7 / PEG-30 phytosterol was 1 part. The formulation and evaluation are shown in Table 2.

[0120] [Example 12] The sample (aqueous slurry) was prepared and evaluated in the same manner as in Example 2, except that the amount of distearyldimethylammonium chloride was 1.4 parts and the amount of PPG-7 / PEG-30 phytosterol was 1.4 parts. The formulation and evaluation are shown in Table 2.

[0121] [Example 13] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of PEG-30 phytosterol (NIKKOL BPS-30, HLB:18, manufactured by Nippon Surfactant Industry Co., Ltd.) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0122] [Example 14] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of PEG-10 phytosterol (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® BPS-10, HLB:13) were added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0123] [Example 15] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of polysorbate 60 (polyoxyethylene sorbitan monostearate (20 E.O.), HLB: 15) (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL TS-10V) were added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0124] [Example 16] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of beheneth 10 (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® BB-10, HLB:10) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0125] [Example 17] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of beheneth 20 (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® BB-20, HLB:12) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0126] [Example 18] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of beheneth 30 (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® BB-30, HLB:14) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0127] [Example 19] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of PEG-60 hydrogenated castor oil (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® HCO-60, HLB:14) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0128] [Example 20] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of PEG-40 hydrogenated castor oil (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® HCO-40, HLB:12) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0129] [Comparative Example 7] The sample was prepared and evaluated in the same manner as in Example 12, except that 1.4 parts of PEG-5 glyceryl stearate (manufactured by Nippon Emulsion Co., Ltd., EMALEX® GM-5, HLB:8) was added as the second surfactant instead of PPG-7 / PEG-30 phytosterol. The formulation and evaluation are shown in Table 2.

[0130] [Comparative Example 8] The sample was prepared and evaluated in the same manner as in Example 2, except that PPG-7 / PEG-30 phytosterol was omitted, the amount of distearyldimethylammonium chloride was set to 10 parts, and the amount of deionized water was set to 60 parts. The formulation and evaluation are shown in Table 2.

[0131] [Example 21] The sample was prepared and evaluated in the same manner as in Example 12, except that 0.22 parts of sodium stearoyl methyl taurate (manufactured by Nippon Surfactant Industry Co., Ltd., NIKKOL® SMT) was further added as a third surfactant (F), and the amount of PPG-7 / PEG-30 phytosterol was set to 1.18 parts. The formulation and evaluation are shown in Table 3.

[0132] [Example 22] The sample was prepared and evaluated in the same manner as in Example 21, except that the amount of PPG-7 / PEG-30 phytosterol was 0.88 parts and the amount of stearoylmethyl taurate sodium was 0.52 parts. The formulation and evaluation are shown in Table 3.

[0133] [Example 23] The sample was prepared and evaluated in the same manner as in Example 21, except that 0.62 parts of sodium stearoyl glutamate (Ajinomoto Co., Ltd., Amisoft® HS-11P(F)) was added instead of sodium stearoyl methyl taurate, and the amount of PPG-7 / PEG-30 phytosterol was set to 0.78 parts. The formulation and evaluation are shown in Table 3.

[0134] [Example 24] The sample was prepared and evaluated in the same manner as in Example 21, except that the amount of PPG-7 / PEG-30 phytosterol was 0.78 parts and the amount of stearoylmethyl taurate sodium was 0.62 parts. The formulation and evaluation are shown in Table 3.

[0135] [Example 25] The sample was prepared and evaluated in the same manner as in Example 22, except that 0.5 parts of (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer (manufactured by Toho Chemical Industry Co., Ltd., SUPOLYMER G-1) were added and the amount of deionized water was increased to 67.5 parts. The formulation and evaluation are shown in Table 3.

[0136] [Example 26] The sample was prepared and evaluated in the same manner as in Example 23, except that 0.5 parts of (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer was added and the amount of deionized water was increased to 67.5 parts. The formulation and evaluation are shown in Table 3.

[0137] [Example 27] The sample was prepared and evaluated in the same manner as in Example 24, except that 0.5 parts of (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer was added and the amount of deionized water was increased to 67.5 parts. The formulation and evaluation are shown in Table 3.

[0138] [Comparative Example 9] The sample was prepared and evaluated in the same manner as in Example 12, except that 0.5 parts of (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer was added and the amount of deionized water was increased to 67.5 parts. The formulation and evaluation are shown in Table 3.

[0139] [Table 1]

[0140] [Table 2]

[0141] [Table 3]

[0142] As shown in Table 1, samples (aqueous slurry) containing distearyldimethylammonium chloride, dipropylene glycol, hydrophobic metal oxide (hydrophobic titanium oxide or hydrophobic zinc oxide), and deionized water as the remainder exhibited good dispersibility and water resistance (Examples 1-8).

[0143] In contrast, samples that did not contain either distearyldimethylammonium chloride or dipropylene glycol exhibited poor dispersibility and unmeasurable water resistance (Comparative Examples 1 and 2). Furthermore, samples containing a non-hydrophobic metal oxide instead of a hydrophobic metal oxide exhibited poor water resistance (Comparative Examples 3 and 4). Additionally, samples containing a hydrophilic surfactant instead of distearyldimethylammonium chloride exhibited poor dispersibility and unmeasurable water resistance (Comparative Example 5), or exhibited poor water resistance (Comparative Example 6).

[0144] These results show that an aqueous slurry containing a hydrophobic powder, one or more first surfactants (B) selected from quaternary ammonium salts, alcohol, and water can disperse the hydrophobic powder not only in the oil phase but also in the aqueous phase, and therefore, when used in cosmetics, it is possible to improve various functions of the cosmetics, such as UV protection, color development, and opacity.

[0145] Furthermore, as shown in Table 2, samples (aqueous slurry) containing a nonionic surfactant with an HLB of 10 or higher in addition to distearyldimethylammonium chloride exhibited good dispersibility, water resistance, and odor stability (Examples 9-20).

[0146] In contrast, the sample containing 1.4 parts of PEG-5 glyceryl stearate (HLB=8) exhibited poor dispersibility and its water resistance could not be measured (Comparative Example 7). Furthermore, the sample containing 10 parts of distearyldimethylammonium chloride exhibited poor odor stability (Comparative Example 8).

[0147] These results indicate that an aqueous slurry containing one or more second surfactants (E) selected from 10 or more nonionic surfactants with an HLB value stabilizes the odor of the aqueous slurry while maintaining high dispersibility and water resistance.

[0148] Table 3 shows that samples (aqueous slurry) further containing sodium stearoylmethyl taurate and sodium stearoyl glutamate in addition to distearyldimethylammonium chloride and the second surfactant (E) also exhibited good dispersibility and water resistance (Examples 21-24).

[0149] When (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer was added to these aqueous slurries as a thickening agent, the thickening of this water-soluble polymer was uniform and did not aggregate (Examples 25-27).

[0150] In contrast, in samples that did not contain either sodium stearoylmethyltaurate or sodium stearoyl glutamate, the polymeric thickener exhibited coagulation properties (Comparative Example 9).

[0151] These results indicate that aqueous slurry further containing one or more third surfactants (F) selected from anionic surfactants can maintain high dispersibility and water resistance, and is less prone to aggregation even when a polymeric thickener is added.

[0152] Although embodiments of the present invention have been described above, the present invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope of the invention as described in the claims.

[0153] This application claims priority based on Japanese Patent Application No. 2021-55611, filed on 29 March 2021, the entire contents of which are incorporated herein by reference.

Claims

1. Hydrophobized metal oxide (A) 0.1% by mass or more and 50% by mass or less, One or more first surfactants (B) selected from quaternary ammonium salts, in an amount of 0.01% to 10% by mass. Alcohol (C) 1% by mass or more and 25% by mass or less, Contains water (D) in an amount of 20% to 99% by mass. Aqueous slurry.

2. The hydrophobic metal oxide (A) is dispersed in a solvent containing the first surfactant (B), the alcohol (C), and the water (D). The aqueous slurry according to claim 1.

3. A mixture of the hydrophobic metal oxide (A), the first surfactant (B), and the alcohol (C) is dispersed in the water (D). The aqueous slurry according to claim 1.

4. The first surfactant (B) is selected from dialkyldimethylammonium chloride represented by the following general formula: The aqueous slurry according to any one of claims 1 to 3. 【Chemistry 1】 (In the formula, R1 represents an alkyl group having 10 to 22 carbon atoms or a benzyl group, R2 represents a methyl group or an alkyl group having 10 to 22 carbon atoms, R3 and R4 represent an alkyl group having 1 to 3 carbon atoms or a hydroxyalkyl group, and X represents a halogen atom or a methyl sulfate residue.)

5. The present invention further comprises one or more second surfactants (E) selected from nonionic surfactants with an HLB of 10 or more. The aqueous slurry according to any one of claims 1 to 4.

6. The present invention further comprises one or more third surfactants (F) selected from anionic surfactants. The aqueous slurry according to any one of claims 1 to 5.

7. The alcohol (C) is at least one selected from lower alcohols and polyhydric alcohols. The aqueous slurry according to any one of claims 1 to 6.

8. An emulsion containing the aqueous slurry described in any one of claims 1 to 7, The dispersed phase of the emulsion contains the aqueous slurry. Emulsion.

9. An emulsion containing the aqueous slurry described in any one of claims 1 to 7, The continuous phase of the emulsion contains the aqueous slurry. Emulsion.

10. The emulsion contains the emulsion described in claim 8 or 9. Cosmetics.

11. A solution containing the aqueous slurry described in any one of claims 1 to 7, Cosmetics.

12. A step of heating and dissolving a mixture of a hydrophobic metal oxide (A) in an amount of 0.1% to 50% by mass, one or more first surfactants (B) selected from quaternary ammonium salts in an amount of 0.01% to 10% by mass, and an alcohol (C) in an amount of 1% to 25% by mass at 80°C to 90°C, The process comprises the step of dispersing the mixture in water (D) in an amount of 20% by mass or more and 99% by mass or less. A method for producing an aqueous slurry.

13. A method for producing a water-in-oil emulsion, in which an aqueous component is dispersed in an oily component, The aqueous component contains the aqueous slurry described in any one of claims 1 to 7. A method for producing a water-in-oil emulsion.

14. A method for producing an oil-in-water emulsion, comprising dispersing an oily component in an aqueous component, The aqueous component contains the aqueous slurry described in any one of claims 1 to 7. A method for producing an oil-in-water emulsion.

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