JP7685351B2 - Oil-in-water emulsion cosmetics - Google Patents

Description

The present invention relates to an oil-in-water emulsion cosmetic that has excellent UV protection effects.

In recent years, as protection from ultraviolet rays has become increasingly important in daily life, the need for sunscreen cosmetics has also increased. In response to such market needs, oil-in-water emulsion sunscreen cosmetics, which have a refreshing feel and are easy to use over time, have been developed.

In these oil-in-water emulsion cosmetics, ultraviolet absorbing agents and ultraviolet scattering agents are used to enhance the ultraviolet ray protection effect. In particular, 2-ethylhexyl paramethoxycinnamate and octocrylene (2-ethylhexyl 2-cyano-3,3-diphenyl-2-propenoate), which are used as ultraviolet ray absorbing agents, have a maximum absorption wavelength in the UVB region and have high affinity with oils, and therefore have been used in many sunscreen cosmetics.
However, these ultraviolet absorbing agents may irritate the skin of users with sensitive skin, and sunscreen cosmetics containing reduced amounts of these ultraviolet absorbing agents have been proposed.
For example, Patent Document 1 describes a sunscreen cosmetic that contains a specific solid ultraviolet absorber, a specific ester oil, and an ultraviolet scattering agent having a refractive index within a specific range in specific blend amounts, with the aim of providing a sunscreen cosmetic that exhibits a high ultraviolet protection effect even when the blend amounts of ethylhexyl methoxycinnamate and octocrylene as liquid ultraviolet absorbents are reduced, and that is also stable and easy to use. The sunscreen cosmetic is described in which the combined blend amount of ethylhexyl methoxycinnamate and octocrylene is 3 mass% or less.

JP 2017-078054 A

However, it has been found that the sunscreen cosmetic composition described in Patent Document 1 does not have sufficient ultraviolet protection effect and emulsion stability, and when applied to the skin, it causes stickiness. Furthermore, when a makeup base or foundation is applied on top of the sunscreen cosmetic composition, the makeup does not adhere well and may become shiny due to sebum.
The objective of the present invention is to provide an oil-in-water emulsion cosmetic which has an excellent ultraviolet protection effect even with low contents of 2-ethylhexyl paramethoxycinnamate and octocrylene, has excellent emulsion stability, is less sticky when applied, spreads well, and suppresses shine caused by sebum.

The present inventors have discovered that an oil-in-water emulsion cosmetic containing a water-insoluble organic UV absorber that is solid at 25°C, a liquid oil, an acrylamide polymer, and a hydrophobically treated fine particle metal oxide, in which the mass ratio of the content of the fine particle metal oxide to the total content of the water-insoluble organic UV absorber and the liquid oil is within a specific range, and the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene used as the liquid oil is equal to or less than a specific value in the total amount of the oil-in-water emulsion cosmetic, can provide a high emulsion stability, excellent UV protection, little stickiness when applied, good makeup application, and reduced shine due to sebum.

That is, the present invention provides an oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), and (C):
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): an acrylamide-based polymer; and component (C): a hydrophobically treated fine particle metal oxide. The mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.25 or more and 1.8 or less,
This is an oil-in-water emulsion cosmetic, in which the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass % or less of the total amount of the oil-in-water emulsion cosmetic.

The present invention can provide an oil-in-water emulsion cosmetic that has excellent UV protection effect even with a low content of 2-ethylhexyl paramethoxycinnamate and octocrylene, has excellent emulsion stability, is less sticky when applied, spreads well, and suppresses shine caused by sebum.

[Oil-in-water emulsion cosmetics]
The oil-in-water emulsion cosmetic of the present invention (hereinafter, also referred to as "emulsion cosmetic") is an oil-in-water emulsion cosmetic containing the following components (A1), (A2), (B), and (C):
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): an acrylamide-based polymer; and component (C): a hydrophobically treated fine particle metal oxide. The mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.25 or more and 1.8 or less,
The total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic.
In the present invention, "containing component (A1), component (A2), component (B), and component (C)" also means "containing component (A1), component (A2), component (B), and component (C) in combination."

In the present invention, "liquid" refers to a state having fluidity under an environment of 1 atmosphere and 25°C, i.e., a state under temperature conditions of the melting point or higher (in the case of an amorphous substance having no melting point, a state under temperature conditions of the melting point or higher). Also, "solid" refers to a state not having fluidity under an environment of 1 atmosphere and 25°C, i.e., a state under temperature conditions below the melting point (in the case of an amorphous substance having no melting point, a state under temperature conditions below the melting point).
In the present invention, the term "water-insoluble" refers to a solubility in water of 1 w/w % or less.

The oil-in-water emulsion cosmetic of the present invention has an excellent ultraviolet protection effect, excellent emulsion stability, little stickiness upon application, good makeup spread, and can suppress shine caused by sebum, even though the contents of 2-ethylhexyl paramethoxycinnamate and octocrylene are low. The reasons for this are unclear, but are thought to be as follows.
In the present invention, the surface of the fine metal oxide particles is hydrophobized, and an acrylamide polymer is used as a thickener for thickening the aqueous phase, which is the continuous phase, so that the fine metal oxide particles can be stably present in the oil phase when applied to an oil-in-water emulsion cosmetic. By setting the mass ratio of the content of the hydrophobized fine metal oxide particles to the total content of the solid water-insoluble organic ultraviolet absorber and the liquid oil agent as the oil agent in the oil phase within a predetermined range, the emulsion stability is improved and ultraviolet rays can be efficiently scattered or absorbed, so that even if the content of 2-ethylhexyl paramethoxycinnamate and octocrylene is low, the ultraviolet protection ability can be improved and stickiness during application can be suppressed. Furthermore, when the oil-in-water emulsion cosmetic of the present invention is applied to the skin, the coating film containing the oil agent and the hydrophobized fine metal oxide particles provides good makeup application and suppresses shine caused by sebum.
Here, 2-ethylhexyl paramethoxycinnamate and octocrylene used as the liquid oil agent are components that cause stickiness upon application, and it is believed that skin shine occurs when these components become compatible with the oil with a high refractive index contained in sebum secreted from the skin. In the present invention, it is believed that by having the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene in the total amount of the oil-in-water emulsion cosmetic be equal to or less than a specific value, it is possible to further improve the effect of suppressing stickiness upon application and shine caused by sebum.

<Component (A1): Water-insoluble organic ultraviolet absorber that is solid at 25° C.>
The oil-in-water emulsion cosmetic of the present invention contains a water-insoluble organic ultraviolet absorber that is solid at 25° C. as component (A1) in order to improve the ultraviolet protection effect.
Examples of component (A1) include 4-tert-butyl-4'-methoxydibenzoylmethane, 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2-hydroxy-4-methoxybenzophenone, drometrizole trisiloxane, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, and 2-ethylhexyl dimethoxybenzylidene dioxoimidazolidinepropionate. These non-water-soluble organic ultraviolet absorbers may be used alone or in combination of two or more.

Among these, component (A1) is preferably 4-tert-butyl-4'-methoxydibenzoylmethane, 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2-hydroxy-4-methoxybenzophenone, drometrizole trisiloxane, and 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-( and more preferably at least one selected from the group consisting of 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, and 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine.
In the oil-in-water emulsion cosmetic of the present invention, component (A1) is preferably present in a state of being dissolved in component (A2).

Commercially available products of component (A1) include "PARSOL 1789" (4-tert-butyl-4'-methoxydibenzoylmethane) (manufactured by DSM); "UVINUL A PLUS" (2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate), "UVINUL T-150" (2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine), "UVINUL M40" (2-hydroxy-4-methoxybenzophenone), "TINOSORB S" (2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine) (all manufactured by BASF); "Mosacare A440" (drometrizole trisiloxane) (manufactured by UFC CORPORATION); "Soft Shade DH" (2-ethylhexyl dimethoxybenzylidene dioxoimidazolidinepropionate) (manufactured by Ajinomoto Co., Inc.), etc.

The content of component (A1) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 0.5% by mass or more, more preferably 0.7% by mass or more, even more preferably 1% by mass or more, and even more preferably 2% by mass or more, from the viewpoint of improving the ultraviolet protection effect, and is preferably 10% by mass or less, more preferably 8% by mass or less, even more preferably 6% by mass or less, and even more preferably 5% by mass or less, from the viewpoint of suppressing stickiness upon application and greasiness due to sebum. More specifically, it is preferably 0.5 to 10% by mass, more preferably 0.7 to 8% by mass, even more preferably 1 to 6% by mass, and even more preferably 2 to 5% by mass.

<Component (A2): Liquid oil>
The oil-in-water emulsion cosmetic of the present invention contains a liquid oil as component (A2) from the viewpoints of dissolving component (A1), incorporating component (C), and improving emulsion stability.
As described above, component (A2) is an oil agent that has fluidity under an atmosphere of 1 atmosphere and 25°C.
The oil-in-water emulsion cosmetic of the present invention may contain a liquid organic ultraviolet absorber as the component (A2) from the viewpoint of further improving the ultraviolet protection effect.

Examples of liquid organic UV absorbers for component (A2) include cinnamic acid-based UV absorbers such as 2-ethylhexyl paramethoxycinnamate, 2-ethoxyethyl paramethoxycinnamate, a mixture of isopropyl paramethoxycinnamate and diisopropyl cinnamate, and methyl bis(trimethylsiloxy)silylisopentyl trimethoxycinnamate; paraaminobenzoic acid-based UV absorbers such as amyl paradimethylaminobenzoate and 2-ethylhexyl paradimethylaminobenzoate; salicylic acid-based UV absorbers such as ethylene glycol salicylate, 2-ethylhexyl salicylate, butyloctyl salicylate, benzyl salicylate, and homomenthyl salicylate; octocrylene; dimethicodiethylbenzalmalonate; and copolymers of adipic acid and neopentyl glycol with the ends blocked with octyldodecanol or cyanodiphenylpropenoic acid. These liquid organic UV absorbents can be used alone or in appropriate combination of two or more.

Examples of commercially available liquid organic UV absorbers include "UVINUL MC80" (2-ethylhexyl paramethoxycinnamate) (manufactured by BASF); "PARSOL 340" (octocrylene) (manufactured by DSM Nutrition Japan); "PARSOL EHS" (2-ethylhexyl salicylate), "PARSOL HMS" (homomenthyl salicylate), "PARSOL SLX" (Polysilicone-15 (INCI name: Polysilicone-15) (dimethicodethylbenzalmalonate)) (all manufactured by DSM); and "Polycrylene" (Polyester-8 (INCI name: Polyester-8) (a copolymer of adipic acid and neopentyl glycol with the ends blocked with octyldodecanol or cyanodiphenylpropenoic acid) (manufactured by Hall Star).

However, from the viewpoint of suppressing stickiness upon application and suppressing shine caused by sebum, the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2% by mass or less, preferably 1.5% by mass or less, more preferably 1% by mass or less, even more preferably 0.7% by mass or less, even more preferably 0.5% by mass or less, even more preferably 0.3% by mass or less, and even more preferably 0% by mass, in other words, 2-ethylhexyl paramethoxycinnamate and octocrylene are not contained.

From the viewpoint of dissolving component (A1), incorporating component (C) and improving emulsion stability, component (A2) preferably contains another liquid oil other than the liquid organic UV absorber. The other liquid oil is not particularly limited as long as it is liquid under an environment of 1 atmospheric pressure and 25° C., and examples of such other liquid oil include oils used in ordinary cosmetics.
The other liquid oils are preferably at least one selected from the group consisting of ester oils, silicone oils, hydrocarbon oils, higher alcohols, and higher fatty acids. The liquid oils may be contained alone or in appropriate combination of two or more.

Examples of ester oils include synthetic ester oils and natural fats and oils, such as esters of monocarboxylic acids and monohydric alcohols, esters of monocarboxylic acids and polyhydric alcohols, and esters of polycarboxylic acids and monohydric alcohols.

Examples of the ester of a monovalent carboxylic acid and a monohydric alcohol include an ester represented by the following general formula (1).
R ¹ -COO-R ² (1)
In general formula (1), R ¹ represents a linear or branched alkyl or alkenyl group having 1 to 25 carbon atoms, or an aromatic hydrocarbon group having 6 to 24 carbon atoms, which may be substituted with a hydroxyl group, and R ² represents a linear or branched alkyl or alkenyl group having 1 to 30 carbon atoms.

When R ¹ is an alkyl group or an alkenyl group, the number of carbon atoms in R ¹ is preferably 7 or more and preferably 23 or less, more preferably 21 or less, even more preferably 19 or less, and still more preferably 17 or less.
When R ¹ is an aromatic hydrocarbon group, the carbon number of R ¹ is preferably 6 or more and preferably 22 or less, more preferably 20 or less.
The number of carbon atoms in ^R2 is preferably 2 or more, and preferably 28 or less, more preferably 24 or less, even more preferably 22 or less, and still more preferably 20 or less.

Specific examples of esters represented by general formula (1) include cetyl isooctanoate (cetyl 2-ethylhexanoate), stearyl isooctanoate, isononyl isononanoate, isotridecyl isononanoate, hexyl laurate, isostearyl laurate, butyl myristate, isopropyl myristate, decyl myristate, isotridecyl myristate, isocetyl myristate, isostearyl myristate, 2-octyldodecyl myristate, isopropyl palmitate, 2-ethylhexyl palmitate, and palmitic acid. The examples include one or more selected from the group consisting of isostearyl phosphate, 2-hexyldecyl palmitate, 2-ethylhexyl stearate, 2-hexyldecyl stearate, isopropyl isostearate, 2-hexyldecyl isostearate, ethyl oleate, isodecyl oleate, oleyl oleate, 2-octyldodecyl oleate, ethyl linoleate, isopropyl linoleate, lanolin acetate, castor oil fatty acid methyl (methyl ricinoleate), and alkyl benzoate (alkyl carbon number 12 to 15).

Examples of the ester of a monovalent carboxylic acid and a monohydric alcohol include an ester represented by the following general formula (2).
R ³ -COO-(AO) _n -R ⁴ (2)
In general formula (2), ^R3 represents a linear or branched alkyl or alkenyl group having 1 to 25 carbon atoms which may be substituted with a hydroxyl group, ^R4 represents an aromatic hydrocarbon group having 6 to 24 carbon atoms, AO represents an alkyleneoxy group having 2 to 4 carbon atoms, and n represents the average number of moles added of 1 to 50.
R ³ is preferably an alkyl group having 7 or more carbon atoms and 23 or less, more preferably 21 or less, and even more preferably 19 or less.
R ⁴ is preferably an aromatic-containing hydrocarbon group having 6 or more carbon atoms and 22 or less, more preferably 20 or less, even more preferably 18 or less, and still more preferably a benzyl group.
The alkyleneoxy group represented by AO is preferably a propyleneoxy group, and n is preferably 1 or more and 10 or less, more preferably 1 or more and 5 or less.
Specific examples of the ester represented by the general formula (2) include an ester of myristic acid and a 3-mol propylene oxide adduct of benzyl alcohol (Croda: Crodamol STS), an ester of 2-ethylhexanoic acid and a 3-mol propylene oxide adduct of benzyl alcohol (Croda: Crodamol SFX), and the like.

Examples of the ester of a monovalent carboxylic acid and a polyhydric alcohol include an ester represented by the following general formula (3).
R ⁵ - (OCOR ⁶ ) _p (3)
In formula (3), ^R5 represents a polyhydric alcohol residue, preferably a hydrocarbon group having 2 to 10 carbon atoms, ^R6 represents a monovalent carboxylic acid residue having 1 to 25 carbon atoms, and p represents an integer of 2 to 10.
^R5 may have an ether bond, but is preferably a linear or branched hydrocarbon group having from 2 to 10 carbon atoms. Also, p is preferably the same number as the number of hydroxy groups contained in the polyhydric alcohol.
^R6 is an alkyl group having preferably 5 or more, more preferably 7 or more, and from the same viewpoint as above, preferably 23 or less, more preferably 21 or less, even more preferably 19 or less, and still more preferably 17 or less.

Examples of the ester represented by the general formula (3) include propylene glycol dicaprate, propylene glycol dioleate, neopentyl glycol dicaprate, neopentyl glycol di-2-ethylhexanoate, di(caprylic/capric)propanediol, propanediol diisostearate, ethylene glycol di-2-ethylhexanoate, tri(caprylic/capric)glyceryl, tri-2-ethylhexanoate, glyceryl tri-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexylate, trimethylolpropane triisostearate, pentaerythritol tetra-2-ethylhexanoate, and natural fats and oils.
Examples of natural fats and oils include triglycerides such as avocado oil, olive oil, sesame oil, rice bran oil, safflower oil, soybean oil, corn oil, rapeseed oil, castor oil, cottonseed oil, and mink oil.

Examples of the esters of polyvalent carboxylic acids and monohydric alcohols include esters represented by the following general formula (4).
R ⁷ -(COOR ⁸ ) _q (4)
In the general formula (4), ^R7 is a polycarboxylic acid residue having 2 to 10 carbon atoms, ^R8 is a monohydric alcohol residue having 1 to 25 carbon atoms, and q is an integer of 2 to 10. In addition, q is preferably the same number as the number of carboxy groups in the polycarboxylic acid.
The number of carbon atoms in R ⁸ is preferably 3 or more, and from the same viewpoint as above, preferably 23 or less, more preferably 21 or less, and even more preferably 19 or less.
Specific examples include diisostearyl malate, di-2-ethylhexyl succinate, diisobutyl adipate, di-2-heptylundecyl adipate, di-2-ethylhexyl sebacate, diisopropyl sebacate, and tri-2-ethylhexyl trimellitate.

Among these, from the viewpoint of dissolving component (A1), incorporating component (C) and improving emulsion stability, the ester oil is preferably an ester represented by general formula (1), general formula (3) or general formula (4), and more preferably a monoester of a linear or branched fatty acid having 8 to 18 carbon atoms and a linear or branched monohydric alcohol having 2 to 24 carbon atoms, a triester of a branched fatty acid having 6 to 18 carbon atoms and glycerin, a tetraester of a branched fatty acid having 6 to 18 carbon atoms and pentaerythritol, a diester of a branched fatty acid having 6 to 18 carbon atoms and a branched dihydric alcohol having 2 to 10 carbon atoms, a triester of a branched monohydric alcohol having 6 to 18 carbon atoms and trimellitic acid, and an alkyl benzoate (C12-15) (for example, "Finsorb TN" (Innospec Active Chemicals It is at least one selected from the group consisting of cetyl 2-ethylhexanoate, isononyl isononanoate, isotridecyl isononanoate, 2-octyldodecyl myristate, isopropyl palmitate, glyceryl tri-2-ethylhexanoate, pentaerythritol tetra-2-ethylhexanoate, diisopropyl sebacate, tri-2-ethylhexyl trimellitate, and alkyl benzoate (C12-15), more preferably at least one selected from the group consisting of cetyl 2-ethylhexanoate, isononyl isononanoate, isotridecyl isononanoate, 2-octyldodecyl myristate, isopropyl palmitate, glyceryl tri-2-ethylhexanoate, pentaerythritol tetra-2-ethylhexanoate, diisopropyl sebacate, tri-2-ethylhexyl trimellitate, and alkyl benzoate (C12-15).

From the viewpoint of dissolving component (A1), incorporating component (C), and improving emulsion stability, the silicone oil is preferably a dimethylpolysiloxane, and more preferably a dimethylpolysiloxane having a kinetic viscosity at 25° C. of 5,000 mm ² /s or less.
The kinetic viscosity of the silicone oil at 25° C. can be measured by an Ubbelohde viscometer in accordance with ASTM D 445-46T or JIS Z 8803.
Commercially available silicone oils include "KF-96A-6cs" (dimethylpolysiloxane), "KF-96A-10cs" (dimethylpolysiloxane), "KF-96A-20cs" (dimethylpolysiloxane), and "KF-96A-100cs" (dimethylpolysiloxane), manufactured by Shin-Etsu Chemical Co., Ltd.

Specific examples of the hydrocarbon oil include liquid paraffin, hydrogenated polyisobutene (liquid isoparaffin, heavy liquid isoparaffin), cycloparaffin, liquid ozokerite, squalene, squalane, pristane, α-olefin oligomer, polybutene, and isohexadecane.
Examples of the higher alcohol include branched or unsaturated higher alcohols having 12 to 24 carbon atoms, such as 2-octyldodecanol, isostearyl alcohol, and oleyl alcohol. Among these, branched or unsaturated higher monohydric alcohols having 12 to 24 carbon atoms are preferred.
Examples of the higher fatty acid include fatty acids having 12 to 22 carbon atoms, such as oleic acid and isostearic acid.

From the viewpoint of dissolving component (A1), incorporating component (C), and improving emulsion stability, component (A2) preferably comprises one or more selected from the group consisting of ester oils and silicone oils, more preferably comprises one or more selected from the group consisting of esters represented by general formula (1), general formula (3), or general formula (4), and dimethylpolysiloxane, and more preferably comprises a monoester of a linear or branched fatty acid having from 8 to 18 carbon atoms and a linear or branched monohydric alcohol having from 2 to 24 carbon atoms, a triester of a branched fatty acid having from 6 to 18 carbon atoms and glycerin, a tetraester of a branched fatty acid having from 6 to 18 carbon atoms and pentaerythritol, a diester of a branched fatty acid having from 6 to 18 carbon atoms and a branched dihydric alcohol having from 2 to 10 carbon atoms, a triester of a branched monohydric alcohol having from 6 to 18 carbon atoms and trimellitic acid, an alkyl benzoate (C12-15), and a kinetic viscosity at 25° C. of 5,000 mm ² and more preferably, it contains one or more selected from the group consisting of cetyl 2-ethylhexanoate, isononyl isononanoate, isotridecyl isononanoate, 2-octyldodecyl myristate, isopropyl palmitate, glyceryl tri-2-ethylhexanoate, pentaerythritol tetra-2-ethylhexanoate, diisopropyl sebacate, tri-2-ethylhexyl trimellitate, alkyl benzoate (C12-15), and dimethylpolysiloxanes having a kinetic viscosity of 5,000 mm ² /s or less at 25° C.

The content of component (A2) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 5% by mass or more, more preferably 7% by mass or more, and even more preferably 10% by mass or more, from the viewpoint of incorporating component (C) and improving emulsion stability, and is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less, and even more preferably 17% by mass or less, from the viewpoint of suppressing stickiness upon application, improving makeup application, and suppressing shine due to sebum. More specifically, it is preferably 5 to 30% by mass, more preferably 7 to 25% by mass, even more preferably 10 to 20% by mass, and even more preferably 10 to 17% by mass.

When component (A2) contains one or more liquid oils selected from the group consisting of ester oils and silicone oils as liquid oils other than the liquid organic UV absorber, the total content of ester oils and silicone oils in component (A2) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and preferably 100% by mass or less.

The mass ratio [(A2)/(A1)] of the content of component (A2) to the content of component (A1) in the total amount of the oil-in-water emulsion cosmetic of the present invention (hereinafter also referred to as the "content mass ratio [(A2)/(A1)]") is preferably 1 or more, more preferably 2 or more, even more preferably 3 or more, still more preferably 4 or more, and even more preferably 5 or more, from the viewpoint of dissolving component (A1) and incorporating component (C) to improve emulsion stability, and is preferably 20 or less, more preferably 15 or less, even more preferably 10 or less, and even more preferably 7 or less, from the viewpoint of improving the ultraviolet protection effect. More specifically, it is preferably 1 to 20, more preferably 2 to 15, even more preferably 3 to 10, even more preferably 4 to 10, even more preferably 4 to 7, and even more preferably 5 to 7.

<Component (B): Acrylamide-Based Polymer>
The oil-in-water emulsion cosmetic of the present invention contains an acrylamide polymer as component (B) from the viewpoints of thickening the aqueous phase, which is the continuous phase, and allowing the fine particle metal oxide to be stably present in the oil phase, thereby improving emulsion stability.
From the same viewpoint as above, component (B) preferably contains one or more structural units derived from an acrylamide monomer selected from the group consisting of acrylamide and acryloyldimethyltaurate (hereinafter also referred to as "AMPS"); more preferably, it is one or more selected from the group consisting of a homopolymer of acrylamide, a homopolymer of AMPS and a salt thereof, and a copolymer containing a structural unit derived from one or more acrylamide monomers selected from the group consisting of acrylamide and AMPS, and a salt thereof; and even more preferably, it is one or more selected from the group consisting of a homopolymer of acrylamide, and a copolymer containing a structural unit derived from one or more acrylamide monomers selected from the group consisting of acrylamide and AMPS, and a salt thereof.

Specific examples of component (B) include polyacrylamide (homopolymer of acrylamide), (acrylamide/acrylic acid) copolymer, (AMPS/acrylic acid) copolymer, (AMPS/acrylamide) copolymer, (AMPS/acrylamide/acrylic acid) copolymer, (AMPS/dimethylacrylamide) copolymer, (AMPS/hydroxyethyl acrylate) copolymer, (AMPS/vinylpyrrolidone) copolymer, (AMPS/vinylformamide) copolymer, (AMPS/polyoxyethylene alkyl ester of methacrylic acid (average number of moles of ethylene oxide added: 10 to 30)) copolymer, and salts thereof.
More specific examples of the copolymer and salts thereof include (Sodium acryloyldimethyl taurate/hydroxyethyl acrylate) copolymer (INCI name: Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer), (Sodium acryloyldimethyl taurate/Sodium acrylate) copolymer (INCI name: Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer), acryloyldimethyl taurate/Sodium acrylate/Dimethylacrylamide) crosspolymer (INCI name: Sodium Acrylate/Acryloyldimethyltaurate/Dimethylacrylamide Crosspolymer), (Ammonium acryloyldimethyltaurate/Vinylpyrrolidone) copolymer (INCI name: Ammonium Acryloyldimethyltaurate/VP Examples of suitable crosspolymers include Ammonium Acryloyldimethyltaurate/Acrylic Acid/Acrylamide/Sodium Acrylate Copolymer (INCI name: Polyacrylate-13), Ammonium Acryloyldimethyltaurate/Dimethylacrylamide/Lauryl Methacrylate/Laureth-4 Methacrylate Crosspolymer (INCI name: Polyacrylate Crosspolymer-6), Ammonium Acryloyldimethyltaurate/Beheneth-25 Methacrylate Crosspolymer (INCI name: Ammonium Acryloyldimethyltaurate/Steareth-25 Methacrylate Crosspolymer), and others.

Commercially available products containing component (B) include "SEPIGEL 501" (polyacrylamide, polysorbate 85, mineral oil, isoparaffin), "SEPIGEL 305" (polyacrylamide, hydrogenated polyisobutene (or (C13,14) isoparaffin), laureth-7, water), "SIMULGEL EG" ((sodium acryloyldimethyltaurate/sodium acrylate) copolymer, isohexadecane, polysorbate 80), "SEPIMAX ZEN" ((ammonium acryloyldimethyltaurate/dimethylacrylamide/lauryl methacrylate/laureth-4 methacrylate) crosspolymer), "SEPINOV EMT 10" ((sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, sorbitan isostearate, polysorbate 60), and "SIMULGEL NS" ((sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, squalane, polysorbate 60, water), "SIMULGEL FL" ((sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, isohexadecane, polysorbate 60, water), "SEPIPLUS S" ((sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, polyisobutene, PEG-7 trimethylolpropane coconut oil alkyl ether, water), "SEPIPLUS 400" ((sodium acryloyldimethyltaurate/acrylic acid/acrylamide/sodium acrylate) copolymer, polyisobutene, polysorbate 20, water) (all manufactured by SEPPIC); "Aristoflex AVC ((ammonium acryloyldimethyltaurate/vinylpyrrolidone) copolymer, t-butanol, water), Aristoflex HMB ((ammonium acryloyldimethyltaurate/beheneth-25 methacrylate) crosspolymer, t-butanol, water), Aristoflex HMS ((ammonium acryloyldimethyltaurate/steareth-25 methacrylate) crosspolymer) (all manufactured by Clariant).

Among these, component (B) is even more preferably one or more selected from the group consisting of polyacrylamide, (sodium acryloyldimethyltaurate/sodium acrylate) copolymer, (sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, and (ammonium acryloyldimethyltaurate/vinylpyrrolidone) copolymer.

The content of component (B) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, from the viewpoint of thickening the aqueous phase, which is the continuous phase, and allowing the fine metal oxide to be stably present in the oil phase and improving emulsion stability, and is preferably 3% by mass or less, more preferably 2% by mass or less, even more preferably 1.5% by mass or less, and even more preferably 1% by mass or less. More specifically, it is preferably 0.1 to 3% by mass, more preferably 0.3 to 2% by mass, even more preferably 0.3 to 1.5% by mass, even more preferably 0.5 to 1.5% by mass, and even more preferably 0.5 to 1% by mass.

<Component (C): Hydrophobically Treated Fine Particle Metal Oxide>
The oil-in-water emulsion cosmetic of the present invention contains, as component (C), fine particles of a hydrophobically treated metal oxide, from the viewpoint of absorbing or scattering ultraviolet light and improving the ultraviolet light protection effect.
From the viewpoint of absorbing or scattering ultraviolet rays and improving ultraviolet protection effect, the fine metal oxide of component (C) is preferably one or more selected from the group consisting of fine zinc oxide, fine titanium oxide, and fine cerium oxide, and more preferably one or more selected from the group consisting of fine zinc oxide and fine titanium oxide.In addition, these fine metal oxides can contain divalent or higher metals, and metals such as iron, zirconium, calcium, manganese, magnesium, yttrium, etc. or their oxides can be contained alone or in appropriate combination of two or more in the fine metal oxide.

Examples of the hydrophobization treatment of component (C) include silicone treatment; alkylalkoxysilane treatment; fatty acid treatment; fluorine-containing compound treatment such as perfluoroalkyl phosphate ester, perfluoroalcohol, etc.; amino acid treatment such as N-acylglutamic acid, etc.; lecithin treatment; metal soap treatment; alkyl phosphate ester treatment; and ASI treatment using N-acylamino acid metal salt (sodium lauroyl aspartate), zinc chloride, and alkoxytitanium alkylate (isopropyl titanium triisostearate).
These surface treatments may be used alone or in combination of two or more.
Among these, the hydrophobization treatment of component (C) is preferably one or more treatments selected from the group consisting of silicone treatment, alkylalkoxysilane treatment, and fatty acid treatment, from the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, and suppressing the squeaky feeling after application and improving the application of makeup.

Examples of surface treatment agents used in silicone treatment include various silicone oils such as methylpolysiloxane, dimethylpolysiloxane (dimethicone), methylphenylpolysiloxane, methylhydrogenpolysiloxane, dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone), methylcyclopolysiloxane, dodecamethylcyclohexasiloxane, tetradecamethylhexasiloxane, dimethylsiloxane/methyl(polyoxyethylene)siloxane/methyl(polyoxypropylene)siloxane copolymer, dimethylsiloxane/methyl(polyoxyethylene)siloxane copolymer, dimethylsiloxane/methyl(polyoxypropylene)siloxane copolymer, dimethylsiloxane/methylcetyloxysiloxane copolymer, dimethylsiloxane/methylstearoxysiloxane copolymer, and (alkyl acrylate/dimethicone) copolymer. Among these, the surface treatment agent used in the silicone treatment is preferably dimethylpolysiloxane (dimethicone), methylhydrogenpolysiloxane, or dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone), with methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone) being more preferred, from the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, and suppressing the squeaky feeling after application and improving the application of makeup.

From the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, as well as suppressing the squeaky feeling after application and improving the application of makeup, the surface treatment agent used in the alkylalkoxysilane treatment is preferably an alkylalkoxysilane having a straight-chain or branched-chain alkyl group having 6 to 20 carbon atoms, more preferably octyltriethoxysilane (triethoxycaprylylsilane) or octyltrimethoxysilane (trimethoxycaprylylsilane), and even more preferably octyltriethoxysilane (triethoxycaprylylsilane).

Examples of the surface treatment agent used in the fatty acid treatment include linear or branched higher fatty acids having 12 to 22 carbon atoms. Among these, the surface treatment agent used in the fatty acid treatment is preferably a linear or branched higher fatty acid having 14 to 22 carbon atoms, more preferably a linear or branched higher fatty acid having 16 to 20 carbon atoms, and even more preferably stearic acid or isostearic acid, from the viewpoint of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, and suppressing the squeaky feeling after application and improving the application of the makeup.

As described above, from the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, and suppressing the squeaky feeling after application and improving the application of makeup, the hydrophobic treatment of component (C) is more preferably one or more selected from the group consisting of silicone treatment using one or more selected from the group consisting of methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer as a surface treatment agent, alkylalkoxysilane treatment, and fatty acid treatment, and even more preferably one or more selected from the group consisting of silicone treatment using one or more selected from the group consisting of methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer as a surface treatment agent, alkylalkoxysilane treatment using alkylalkoxysilane having a linear or branched alkyl group having 6 to 20 carbon atoms as a surface treatment agent, and fatty acid treatment using linear or branched higher fatty acid having 14 to 22 carbon atoms as a surface treatment agent.

The above-mentioned surface treatment agents may be used alone or in combination of two or more.
When titanium oxide is used as the metal oxide of component (C), from the viewpoint of reducing photocatalytic activity, a treatment agent such as silica, hydrous silica, or a hydrous oxide of a metal such as aluminum may be used in combination with the surface treatment agent used in the hydrophobization treatment described above.

The amount of the hydrophobization treatment in component (C) is, from the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic and improving the UV protection effect and emulsion stability, as well as of suppressing the squeaky feeling after application and improving the application of makeup, preferably 0.1% by mass or more and preferably 40% by mass or less, more preferably 30% by mass or less of component (C).
In the present invention, the mass of component (C) and the average primary particle size described below mean the mass and average primary particle size including the surface treatment agent.

The shape of component (C) may be, for example, spherical, flake, plate, rod, spindle, needle, or irregular, but any shape can be used.
From the viewpoint of improving the ultraviolet protection effect and emulsion stability, the average primary particle size of component (C) is preferably 1 μm or less, more preferably 800 nm or less, more preferably 500 nm or less, even more preferably 300 nm or less, even more preferably 200 nm or less, even more preferably 100 nm or less, even more preferably 90 nm or less, even more preferably 50 nm or less, even more preferably 40 nm or less, and from the viewpoint of versatility, it is preferably 1 nm or more, more preferably 5 nm or more, even more preferably 10 nm or more. More specifically, from the viewpoints similar to those described above, the average primary particle size of component (C) is preferably 1 nm to 1 μm, more preferably 1 to 800 nm, even more preferably 5 to 500 nm, even more preferably 5 to 300 nm, even more preferably 5 to 200 nm, even more preferably 5 to 100 nm, even more preferably 5 to 90 nm, even more preferably 5 to 50 nm, even more preferably 10 to 50 nm, even more preferably 10 to 40 nm.

The average primary particle diameter of component (C) in the present invention can be determined from an image observed with a transmission electron microscope (TEM). Specifically, the TEM is used to observe at a magnification of 50,000 times, and the maximum short diameter of 300 primary particles in the observed image is measured, and the number average value is calculated. Here, the maximum short diameter means the short diameter having the maximum length among the short diameters perpendicular to the long diameter, when component (C) has a shape other than a flaky or plate-like shape. In addition, when component (C) has a flaky or plate-like shape, the thickness of 300 primary particles in the observed image observed under the same conditions as above is measured, and the number average value is calculated. Specifically, it is measured by the method described in the examples.

Component (C) can be prepared by a known method using the above-mentioned surface treatment agent from the fine metal oxide before hydrophobization treatment as component (C'). For example, as described in Japanese Patent No. 3187440, the surface treatment using the silicone oil can be prepared by coating the surface of the fine metal oxide such as fine zinc oxide with at least one silicone compound (excluding silane compounds) composed of organopolysiloxanes and silicone resin in a non-gas phase state, and then baking at a temperature of 600 to 950 ° C. in an oxygen-containing atmosphere to coat the surface of the fine metal oxide with silicon oxide. In addition, as described in Japanese Patent Publication No. 2007-326902, the surface treatment using the alkylalkoxysilane can be prepared by coating the fine metal oxide with a specific polysiloxane compound, and then surface treating the surface with the alkylalkoxysilane in water.
The preferred embodiment and measuring method of the average primary particle size of component (C') (fine particle metal oxide before hydrophobization treatment) used in the above-mentioned hydrophobization treatment are the same as the preferred embodiment and measuring method of component (C).

Commercially available hydrophobically treated zinc oxide particles include the FINEX series (manufactured by Sakai Chemical Industry Co., Ltd.), the MZ series, and the MZY series (all manufactured by Teika Corporation).
Commercially available hydrophobically treated titanium dioxide particles include the STR series (manufactured by Sakai Chemical Industry Co., Ltd.), the TTO-55 series, the TTO-51 series (all manufactured by Ishihara Sangyo Kaisha, Ltd.), the MT series, and the MTY series (all manufactured by Teika Corporation).

The content of component (C) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 7% by mass or more, and even more preferably 10% by mass or more, from the viewpoint of improving the ultraviolet protection effect, and is preferably 30% by mass or less, more preferably 27% by mass or less, even more preferably 25% by mass or less, and even more preferably 20% by mass or less, from the viewpoint of improving the emulsion stability. More specifically, from the viewpoint of improving the ultraviolet protection effect and improving the emulsion stability, the content is preferably 1 to 30% by mass, more preferably 3 to 30% by mass, even more preferably 7 to 27% by mass, even more preferably 7 to 25% by mass, even more preferably 10 to 25% by mass, and even more preferably 10 to 20% by mass.

The mass ratio [(C)/(A1+A2)] of the content of component (C) to the combined content of components (A1) and (A2) in the total amount of the oil-in-water emulsion cosmetic of the present invention (hereinafter also referred to as the "content mass ratio [(C)/(A1+A2)]") is 0.25 or more, preferably 0.30 or more, more preferably 0.40 or more, even more preferably 0.50 or more, and still more preferably 0.60 or more, from the viewpoint of improving the UV protection effect and emulsion stability, and from the viewpoint of improving the application of makeup and suppressing shine due to sebum, and is 1.8 or less, preferably 1.5 or less, more preferably 1.3 or less, even more preferably 1.0 or less, and still more preferably 0.80 or less, from the viewpoint of suppressing stickiness upon application. More specifically, it is preferably 0.30 to 1.5, more preferably 0.40 to 1.3, even more preferably 0.50 to 1.0, even more preferably 0.50 to 0.80, and even more preferably 0.60 to 0.80.

In addition to components (A1), (A2), (B), and (C), the oil-in-water emulsion cosmetic of the present invention may contain optional components used according to the intended use of the cosmetic, as long as the effects of the present invention are not impaired. Examples of such optional components include ultraviolet absorbers, oils, surfactants, water-soluble polymers, neutralizing agents, pH adjusters, bactericides, anti-inflammatory agents, preservatives, colorants, chelating agents, whitening agents, antiperspirants, insect repellents, bioactive ingredients, salts, antioxidants, fragrances, etc., other than components (A1), (A2), (B), and (C).

<Component (D): Polyhydric alcohol>
It is preferable that the oil-in-water emulsion cosmetic of the present invention further contains a polyhydric alcohol as component (D) from the viewpoints of suppressing stickiness upon application and improving makeup application.
Examples of the component (D) include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (average molecular weight less than 650), 1,2-propanediol (propylene glycol), 1,3-propanediol (propanediol), dipropylene glycol, polypropylene glycol (average molecular weight less than 650), isoprene glycol, and 1,3-butylene glycol; and trihydric or higher polyhydric alcohols such as glycerin, diglycerin, and polyglycerin. Among these, component (D) is preferably a polyhydric alcohol having from 2 to 12 carbon atoms, more preferably a polyhydric alcohol having from 2 to 6 carbon atoms, still more preferably one or more selected from the group consisting of ethylene glycol, diethylene glycol, 1,2-propanediol (propylene glycol), 1,3-propanediol (propanediol), dipropylene glycol, 1,3-butylene glycol, and glycerin, and still more preferably one or more selected from the group consisting of propanediol, dipropylene glycol, 1,3-butylene glycol, and glycerin. These alcohols can be used alone or in combination of two or more.

From the viewpoints of suppressing stickiness upon application and improving the application of the makeup, the content of component (D) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, still more preferably 3% by mass or more, still more preferably 4% by mass or more, still more preferably 5% by mass or more, and is preferably 15% by mass or less, more preferably 13% by mass or less, and even more preferably 10% by mass or less. More specifically, it is preferably 0.5 to 15% by mass, more preferably 1 to 13% by mass, even more preferably 2 to 13% by mass, still more preferably 3 to 10% by mass, still more preferably 4 to 10% by mass, and even more preferably 5 to 10% by mass.
The content of component (D) in the total amount of the oil-in-water emulsion cosmetic of the present invention is, from the viewpoints of suppressing stickiness upon application, improving the spread of the makeup, and suppressing shine due to sebum, preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, still more preferably 3% by mass or more, and preferably 15% by mass or less, more preferably 13% by mass or less, even more preferably 10% by mass or less, still more preferably 7% by mass or less, and still more preferably 5% by mass or less. More specifically, it is preferably 0.5 to 15% by mass, more preferably 1 to 13% by mass, even more preferably 2 to 13% by mass, still more preferably 3 to 10% by mass, still more preferably 3 to 7% by mass, and still more preferably 3 to 5% by mass.

<Component (E): Surfactant>
From the viewpoint of obtaining good emulsion stability, it is preferable that the oil-in-water emulsion cosmetic of the present invention further contains a surfactant as component (E).
The component (E) is not particularly limited, and any of nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants can be used. These can be used alone or in combination of two or more.

Among these, component (E) is preferably a nonionic surfactant, such as sorbitan fatty acid ester, polyoxyalkylene hydrogenated castor oil, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene alkyl ether, polyether modified silicone, etc. Specific examples include sorbitan monostearate, sorbitan monoisostearate, polyoxyethylene hydrogenated castor oil (average EO added moles 60), polyoxyethylene hydrogenated castor oil (average EO added moles 40), polyoxyethylene sorbitan monolaurate (average EO added moles 20), polyoxyethylene sorbitan monostearate (average EO added moles 20), polyoxyethylene sorbitan oleate (average EO added moles 20), polyoxyethylene (average EO added moles 7) lauryl ether, polyoxyethylene (average EO added moles 7) trimethylolpropane coconut oil alkyl ether, dimethicone copolyol, etc. These nonionic surfactants may be used alone or in combination of two or more.

The content of component (E) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, and is preferably 3% by mass or less, more preferably 2% by mass or less, even more preferably 1% by mass or less. More specifically, it is preferably 0.1 to 3% by mass, more preferably 0.3 to 2% by mass, even more preferably 0.5 to 1% by mass.

<Component (F): Other Water-Soluble Polymers>
From the viewpoint of obtaining good emulsion stability, the oil-in-water emulsion cosmetic of the present invention preferably further contains, as component (F), a water-soluble polymer other than component (B) that has a thickening effect.
There are no limitations on component (F) so long as it is one that is commonly used in cosmetics, and any of natural polymers, semi-synthetic polymers, and synthetic polymers other than component (B) can be used.

Examples of natural polymers include xanthan gum, carrageenan, alginic acid, etc. Among them, xanthan gum is preferred from the viewpoint of obtaining good emulsion stability.
Examples of the semi-synthetic polymer include modified polysaccharides such as hydroxycellulose, hydroxypropylcellulose, sodium carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, and cationic cellulose.
Examples of synthetic polymers other than component (B) include acrylic polymers other than component (B), such as carbomer (crosslinked polyacrylic acid), polyacrylic acid, sodium polyacrylate, and (acrylic acid/alkyl methacrylate) copolymers; polyvinylpyrrolidone, polyvinyl alcohol, and cationized polyvinylpyrrolidone.

Commercially available carbomer products include "Carbopol 910", "Carbopol 934", "Carbopol 940", "Carbopol 941", "Carbopol 980", and "Carbopol 981" (all manufactured by Lubrizol Advanced Materials).
Commercially available products of (acrylic acid/alkyl methacrylate) copolymers include "Carbopol 1382", "Carbopol ETD2020", "PEMULEN TR-1", and "PEMULEN TR-2" (all manufactured by Lubrizol Advanced Materials).

The content of component (F) in the total amount of the oil-in-water emulsion cosmetic of the present invention is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.07% by mass or more, from the viewpoint of obtaining good emulsion stability, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, from the viewpoint of obtaining a good feeling of use. More specifically, it is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, and even more preferably 0.07 to 1% by mass.

(aqueous medium)
The oil-in-water emulsion cosmetic of the present invention contains at least water as an aqueous medium in addition to component (D). In the present invention, the aqueous medium other than component (D) and water may further contain, for example, a saturated monohydric alcohol having from 1 to 3 carbon atoms, such as ethanol, propyl alcohol, isopropyl alcohol, etc.
The content of the aqueous medium other than component (D) in the total amount of the oil-in-water emulsion cosmetic of the present invention may be within a range that allows the composition to become an oil-in-water emulsion cosmetic, and from the viewpoint of improving emulsion stability, is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, still more preferably 55% by mass or more, still more preferably 60% by mass or more, and is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less. More specifically, it is preferably 40 to 90% by mass, more preferably 45 to 80% by mass, even more preferably 50 to 75% by mass, still more preferably 55 to 75% by mass, and even more preferably 60 to 75% by mass.

The oil-in-water emulsion cosmetic of the present invention can be suitably used as hair cosmetics such as shampoos, rinses, conditioners, etc., and skin cosmetics such as facial cleansers, cleansing cosmetics, sunscreen cosmetics, packs, massage cosmetics, etc. Among these, the oil-in-water emulsion cosmetic of the present invention has excellent ultraviolet protection effect, and is therefore preferably applied for sunscreen purposes such as sunscreen cosmetics (lotion, cream, milky lotion, serum, etc.), suntan, makeup base cosmetics, foundations, etc.
The oil-in-water emulsion cosmetic of the present invention can be in the form of a liquid, emulsion, cream, paste, solid, multi-layer, etc., and can also be used as a sheet, spray, or mousse.

(Method for producing oil-in-water emulsion cosmetic)
The method for producing the oil-in-water emulsion cosmetic of the present invention is not particularly limited, and any known method can be used appropriately depending on the formulation of the oil-in-water emulsion cosmetic. For example, there is a method including a step of blending component (A1), component (A2), component (B), component (C), and the optional components described above as necessary, and mixing them uniformly using a homomixer or the like.

As a method for producing the oil-in-water emulsion cosmetic of the present invention, from the viewpoints of increasing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, improving the UV protection effect and emulsion stability, and suppressing stickiness upon application, improving the makeup application, and suppressing shine due to sebum, a method comprising a step of mixing and emulsifying a dispersion of component (C) in an oil phase component comprising component (A1), component (A2), and, if necessary, the above-mentioned oil-soluble optional component, with a preparation of an aqueous phase component comprising component (B), an aqueous medium, and, if necessary, the above-mentioned water-soluble optional component, is more preferable, and a method comprising the following steps I to III is more preferable.
Step I: A step of adding component (C) to component (A1), component (A2), and, if necessary, the aforementioned optional oil-soluble component, and uniformly mixing to obtain a dispersion (i) in which component (C) is dispersed. Step II: A step of uniformly mixing an aqueous phase component containing component (B), an aqueous medium, and, if necessary, the aforementioned optional water-soluble component to obtain a preparation (ii). Step III: A step of adding dispersion (i) obtained in step I to preparation (ii) obtained in step II, and uniformly mixing and emulsifying to obtain an oil-in-water emulsion cosmetic.

From the viewpoint of enhancing the dispersibility of component (C) in the oil-in-water emulsion cosmetic, step I preferably includes the following steps I-1 and I-2.
Step I-1: A step of uniformly mixing the oil phase components including the component (A1), the component (A2), and, if necessary, the oil-soluble optional component described above to obtain a preparation (i'). Step I-2: A step of adding the component (C) to the preparation (i') obtained in step I-1, uniformly mixing, and obtaining a dispersion (i) in which the component (C) is dispersed.

The mixing of the oil phase components in step I-1 and the mixing of the aqueous phase components in step II are each preferably carried out with stirring while heating at a temperature in the range of 20° C. or higher and 90° C. or lower.
In step II, the resulting preparation (ii) is preferably cooled to a temperature range of 15° C. or more and 35° C. or less, and then mixed uniformly to obtain the preparation (ii).
In step III, it is preferable to add the dispersion (i) obtained in step I while stirring the preparation (ii) obtained in step II, preferably maintaining the temperature at 30° C. or higher and 90° C. or lower, and mix and emulsify uniformly.

In relation to the above-mentioned embodiment, the present invention further discloses the following embodiments.
<1> An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), and (C):
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): one or more selected from the group consisting of acrylamide homopolymers, and copolymers containing structural units derived from one or more acrylamide-based monomers selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof; component (C): one or more selected from the group consisting of hydrophobically treated fine particle zinc oxide and fine particle titanium oxide; the mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.30 or more and 1.5 or less,
An oil-in-water emulsion cosmetic, in which the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less based on the total amount of the oil-in-water emulsion cosmetic.

<2> The oil-in-water emulsion cosmetic according to the above <1>, further comprising a polyhydric alcohol as a component (D).
<3> The oil-in-water emulsion cosmetic according to <2> above, wherein the content of the component (D) in the total amount of the oil-in-water emulsion cosmetic is 1% by mass or more and 13% by mass or less.
<4> The oil-in-water emulsion cosmetic according to <2> or <3>, wherein the content of the component (D) in the total amount of the oil-in-water emulsion cosmetic is 3% by mass or more and 10% by mass or less.

<5> The oil-in-water emulsion cosmetic according to any one of <1> to <4> above, wherein the combined content of 2-ethylhexyl paramethoxycinnamate and octocrylene is 0.7 mass% or less of the total amount of the oil-in-water emulsion cosmetic.
<6> The oil-in-water emulsion cosmetic according to any one of <1> to <4> above, wherein the combined content of 2-ethylhexyl paramethoxycinnamate and octocrylene is 0.3 mass% or less in the total amount of the oil-in-water emulsion cosmetic.
<7> The oil-in-water emulsion cosmetic according to any one of the items <1> to <6>, wherein the mass ratio [(C)/(A1+A2)] of the content of component (C) to the combined content of components (A1) and (A2) in the total amount of the oil-in-water emulsion cosmetic is 0.40 or more and 1.3 or less.

<8> The oil-in-water emulsion cosmetic according to any one of <1> to <7> above, wherein the hydrophobization treatment of component (C) is one or more treatments selected from the group consisting of a silicone treatment, an alkylalkoxysilane treatment, and a fatty acid treatment.
<9> The oil-in-water emulsion cosmetic according to any one of <1> to <7> above, wherein the hydrophobization treatment of component (C) is one or more selected from the group consisting of a silicone treatment using one or more selected from the group consisting of methylhydrogenpolysiloxane, and dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone) as a surface treatment agent, an alkylalkoxysilane treatment, and a fatty acid treatment.
<10> The oil-in-water emulsion cosmetic according to any one of <1> to <9> above, wherein the average primary particle size of component (C) is 1 nm or more and 800 nm or less.
<11> The oil-in-water emulsion cosmetic according to any one of <1> to <9> above, wherein the average primary particle size of component (C) is 5 nm or more and 100 nm or less. <12> The oil-in-water emulsion cosmetic according to any one of <1> to <11> above, wherein the content of component (C) in the total amount of the oil-in-water emulsion cosmetic is 3 mass% or more and 30 mass% or less.
<13> The oil-in-water emulsion cosmetic according to any one of <1> to <11>, wherein the content of the component (C) in the total amount of the oil-in-water emulsion cosmetic is 7% by mass or more and 25% by mass or less.
<14> The oil-in-water emulsion cosmetic according to any one of <1> to <13>, wherein the content of the component (B) in the total amount of the oil-in-water emulsion cosmetic is 0.1% by mass or more and 3% by mass or less.
<15> The oil-in-water emulsion cosmetic according to any one of <1> to <13>, wherein the content of the component (B) in the total amount of the oil-in-water emulsion cosmetic is 0.3 mass % or more and 2 mass % or less.

<16> The oil-in-water emulsion cosmetic according to any one of <1> to <15> above, wherein the component (B) is one or more selected from the group consisting of polyacrylamide, (sodium acryloyldimethyltaurate/sodium acrylate) copolymer, (sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, and (ammonium acryloyldimethyltaurate/vinylpyrrolidone) copolymer.
<17> The oil-in-water emulsion cosmetic according to any one of the items <1> to <16>, wherein the component (A2) comprises one or more oils selected from the group consisting of ester oils and silicone oils.
<18> The oil-in-water emulsion cosmetic according to any one of <1> to <17> above, wherein component (A1) is one or more selected from the group consisting of 4-tert-butyl-4'-methoxydibenzoylmethane, 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2-hydroxy-4-methoxybenzophenone, drometrizole trisiloxane, and 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine.
<19> The oil-in-water emulsion cosmetic according to any one of <1> to <18> above, for use in a sunscreen application.

<20> An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), (C), and (D),
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): one or more selected from the group consisting of acrylamide homopolymers, and copolymers containing structural units derived from one or more acrylamide-based monomers selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof; component (C): one or more selected from the group consisting of hydrophobically treated fine zinc oxide and fine titanium oxide particles having an average primary particle diameter of 1 nm or more and 800 nm or less; component (D): a polyhydric alcohol; and a mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.30 or more and 1.5 or less,
the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic;
The content of component (D) is 1% by mass or more and 13% by mass or less,
An oil-in-water emulsion cosmetic used for sunscreen purposes.

<21> An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), (C), and (D),
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): one or more selected from the group consisting of acrylamide homopolymers, and copolymers containing structural units derived from one or more acrylamide-based monomers selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof; component (C): one or more selected from the group consisting of hydrophobically treated fine zinc oxide and fine titanium oxide particles having an average primary particle diameter of 5 nm or more and 100 nm or less; component (D): a polyhydric alcohol; and a mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.40 or more and 1.3 or less,
the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic;
The content of component (D) is 3% by mass or more and 10% by mass or less,
An oil-in-water emulsion cosmetic used for sunscreen purposes.

<22> An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), and (C),
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): one or more selected from the group consisting of acrylamide homopolymers, and copolymers containing structural units derived from one or more acrylamide-based monomers selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof; component (C): one or more selected from the group consisting of hydrophobically treated fine zinc oxide and fine titanium oxide particles having an average primary particle diameter of 5 nm or more and 100 nm or less; the mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.40 or more and 1.3 or less,
the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic;
the hydrophobization treatment of component (C) is at least one selected from the group consisting of a silicone treatment using at least one selected from the group consisting of methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone) as a surface treatment agent, an alkylalkoxysilane treatment, and a fatty acid treatment;
An oil-in-water emulsion cosmetic used for sunscreen purposes.

<23> An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), (C), and (D),
component (A1): a water-insoluble organic ultraviolet absorber that is solid at 25°C; component (A2): a liquid oil; component (B): one or more selected from the group consisting of acrylamide homopolymers, and copolymers containing structural units derived from one or more acrylamide-based monomers selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof; component (C): one or more selected from the group consisting of hydrophobically treated fine zinc oxide and fine titanium oxide particles having an average primary particle diameter of 5 nm or more and 100 nm or less; component (D): a polyhydric alcohol; and a mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.40 or more and 1.3 or less,
the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic;
the hydrophobization treatment of component (C) is at least one selected from the group consisting of a silicone treatment using at least one selected from the group consisting of methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer (hydrogen dimethicone) as a surface treatment agent, an alkylalkoxysilane treatment, and a fatty acid treatment;
The content of component (D) is 1% by mass or more and 13% by mass or less,
An oil-in-water emulsion cosmetic used for sunscreen purposes.

<24> The oil-in-water emulsion cosmetic according to any one of <20> to <23> above, wherein the combined content of 2-ethylhexyl paramethoxycinnamate and octocrylene is 0.7% by mass or less, based on the total amount of the oil-in-water emulsion cosmetic.
<25> The oil-in-water emulsion cosmetic according to any one of <20> to <23> above, wherein the combined content of 2-ethylhexyl paramethoxycinnamate and octocrylene is 0.3 mass% or less, based on the total amount of the oil-in-water emulsion cosmetic.
<26> The oil-in-water emulsion cosmetic according to any one of <20> to <25> above, wherein the content of the component (C) in the total amount of the oil-in-water emulsion cosmetic is 3% by mass or more and 30% by mass or less.
<27> The oil-in-water emulsion cosmetic according to any one of <20> to <25> above, wherein the content of the component (C) in the total amount of the oil-in-water emulsion cosmetic is 7% by mass or more and 25% by mass or less.
<28> The oil-in-water emulsion cosmetic according to any one of <20> to <27> above, wherein the content of the component (B) in the total amount of the oil-in-water emulsion cosmetic is 0.1% by mass or more and 3% by mass or less.
<29> The oil-in-water emulsion cosmetic according to any one of <20> to <27> above, wherein the content of the component (B) in the total amount of the oil-in-water emulsion cosmetic is 0.3 mass% or more and 2 mass% or less.

<30> The oil-in-water emulsion cosmetic according to any one of <20> to <29> above, wherein component (B) is one or more selected from the group consisting of polyacrylamide, (sodium acryloyldimethyltaurate/sodium acrylate) copolymer, (sodium acryloyldimethyltaurate/hydroxyethyl acrylate) copolymer, and (ammonium acryloyldimethyltaurate/vinylpyrrolidone) copolymer.
<31> The oil-in-water emulsion cosmetic according to any one of <20> to <30> above, wherein the component (A2) comprises one or more oils selected from the group consisting of ester oils and silicone oils.
<32> The oil-in-water emulsion cosmetic according to any one of the above <20> to <31>, wherein component (A1) is one or more selected from the group consisting of 4-tert-butyl-4'-methoxydibenzoylmethane, 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2-hydroxy-4-methoxybenzophenone, drometrizole trisiloxane, and 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine.

The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these.

(Average primary particle size of component (C) and component (C'))
The average primary particle diameters of components (C) and (C') were measured by the following method.
When the measurement sample has a shape other than a flake or plate, a dispersion of the measurement sample prepared in advance is placed on the sample stage of a transmission electron microscope (TEM) (trade name "JEM1400Plus", manufactured by JEOL Ltd.) and air-dried, and the maximum short diameters of 300 primary particles in an image observed with the TEM at a magnification of 50,000 times are measured, and the number average value is taken as the average primary particle diameter. Here, the maximum short diameter means the short diameter having the greatest length among the short diameters perpendicular to the long diameter.
When the measurement sample had a flake or plate-like shape, the thicknesses of 300 primary particles in an image observed under the same method and magnification conditions as above were measured, and the number average value was taken as the average primary particle diameter.
The dispersion of the measurement sample was prepared by adding 95 g of ethanol as a solvent to 5 g of the measurement sample and subjecting the mixture to ultrasonic dispersion.

Preparation Example 1 (Preparation of Dimethicone-treated Zinc Oxide Microparticles C1)
88 parts by mass of zinc oxide fine particles (approximately spherical, average primary particle diameter 25 nm) as component (C') and 12 parts by mass of dimethylpolysiloxane (dimethicone) (dynamic viscosity 20 ^mm2 /s, manufactured by Shin-Etsu Chemical Co., Ltd.) as a surface treatment agent were added to toluene and thoroughly stirred, and then the toluene was removed by heating under reduced pressure. The obtained powder was pulverized using an atomizer. Next, a calcination treatment was performed in air at 800°C for 2 hours using a high-temperature heating furnace, and dimethicone-treated zinc oxide fine particles C1 was obtained as component (C).

Preparation Example 2 (Preparation of Methylhydrogenpolysiloxane-Treated Zinc Oxide Microparticles C2)
A slurry was prepared from 93 parts by mass of zinc oxide fine particles (approximately spherical, average primary particle diameter 35 nm) as component (C'), 7 parts by mass of methylhydrogenpolysiloxane ("KF-99P" manufactured by Shin-Etsu Chemical Co., Ltd.) as a surface treatment agent, and isopropyl alcohol. The slurry was thoroughly stirred and pulverized, and the solvent was distilled off by heating under reduced pressure. The slurry was then heat-treated in air at 150°C for 4 hours to obtain methylhydrogenpolysiloxane-treated zinc oxide fine particles C2 as component (C).

Preparation Example 3 (Preparation of triethoxycaprylylsilane-treated zinc oxide microparticles C3)
As component (C'), 93 parts by mass of zinc oxide fine particles (approximately spherical, average primary particle diameter 35 nm), 7 parts by mass of octyltriethoxysilane (triethoxycaprylylsilane) as surface treatment agent, and slurry consisting of toluene are prepared, and are pulverized and disintegrated using a bead mill (Dyno Mill manufactured by Shinmaru Enterprises Co., Ltd.). Then, toluene is heated and distilled off under reduced pressure, and then heat-treated at 150°C for 4 hours using a blower type dryer, to obtain triethoxycaprylylsilane-treated zinc oxide fine particles C3 as component (C).

Preparation Example 4 (Preparation of Dimethicone-treated Titanium Dioxide Microparticle C4)
88 parts by mass of titanium dioxide fine particles (approximately spherical, average primary particle diameter 10 nm) as component (C') and 12 parts by mass of dimethylpolysiloxane (dimethicone) (dynamic viscosity 20 ^mm2 /s, manufactured by Shin-Etsu Chemical Co., Ltd.) as a surface treatment agent were added to toluene and thoroughly stirred, and then the toluene was removed by heating under reduced pressure. The obtained powder was pulverized using an atomizer. Then, using a high-temperature heating furnace, a calcination treatment was carried out in air at 800°C for 2 hours, and dimethicone-treated titanium dioxide fine particles C4 were obtained as component (C).

Examples 1 to 26, Comparative Examples 1 to 6, Reference Example 1
According to the formulations shown in Tables 1 to 4, oil-in-water emulsion cosmetics were obtained by the following method.
Components 1 to 21 and 46 shown in Tables 1 to 4 were mixed uniformly, heated to 80°C, and dissolved to obtain preparation (i') (step I-1). Next, while maintaining the obtained preparation (i') at 80°C, components 27 to 33 shown in Tables 1 to 4 were added, mixed uniformly, and dispersed to obtain dispersion (i) (step I-2).
Separately, components 22 to 26, 34 to 45, 49, and 50 shown in Tables 1 to 4 were heated to 40°C and dissolved, and then naturally cooled to 25°C. After that, components 47 and 48 were added and mixed uniformly to obtain preparation (ii) (step II).
While stirring the obtained preparation (ii), the dispersion (i) kept at 80° C. was added, and the mixture was uniformly mixed with a homomixer to emulsify, thereby obtaining an oil-in-water emulsion cosmetic (Step III).

The obtained oil-in-water emulsion cosmetic was evaluated for (1) UV protection ability, (2) emulsion stability, and (3) usability (lack of stickiness upon application, ease of makeup application immediately after application, and lack of shine due to sebum 3 hours after application) as shown below.
In addition, for Comparative Examples 2 and 3, immediately after preparation, the compositions were inhomogeneous and separated into an oil phase and an aqueous phase, so only the emulsion stability was evaluated, and the UV protection ability and usability were not evaluated.
The results are shown in Tables 1 to 4.

(1) UV protection ability The oil-in-water emulsion cosmetics shown in Tables 1 to 4 were uniformly applied to a square PMMA plate ("HD6" manufactured by HelioScreen) in an amount of 1.3 mg/ ^cm2 and allowed to dry naturally for 15 minutes to prepare a measurement sample. Each sample was irradiated with UV light from a fixed distance (10 mm) using an SPF analyzer (Optometices). The transmitted UV light was detected by the SPF analyzer at 10 points on each sample in the wavelength range of 290 to 400 nm, and an averaged spectrum was obtained to calculate the SPF value.
From each SPF value, the improvement rate of UV protection ability relative to Reference Example 1 not containing component (A1) (compound (A1) in the formulation of Example 1 was replaced with purified water) was calculated according to the following formula, and evaluated according to the following evaluation criteria.
UV protection improvement rate (%)=[(SPF value of Example or Comparative Example)/(SPF value of Reference Example 1)]×100
[Evaluation criteria for UV protection improvement rate]
5: 250% or more 4: 200% or more but less than 250% 3: 150% or more but less than 200% 2: 100% or more but less than 150% 1: Less than 100%

(2) Emulsion Stability Immediately after preparation of the oil-in-water emulsion cosmetics shown in Tables 1 to 4, the emulsion state was observed using a microscope and visually inspected, and evaluated according to the following criteria.
〔Judgment criteria〕
5: Component (C) penetrates into the internal phase (oil phase), the particle size distribution is very narrow in the range of 10 to 50 μm, and there is no coalescence of the emulsion particles, forming beautiful, roughly spherical emulsion particles. Visual observation reveals a glossy, beautiful appearance.
4: Component (C) penetrates into the internal phase (oil phase), the emulsion particle size is in the range of 10 to 100 μm with a narrow particle size distribution, there is no coalescence of the emulsion particles, and neat, roughly spherical emulsion particles are formed. Visual inspection also shows a neat appearance with no roughness.
3: Component (C) penetrates into the internal phase (oil phase) and emulsion particles are formed, but coalescence of the emulsion particles occurs from the day after preparation onwards.
2: Although component (C) is incorporated into the internal phase (oil phase), the emulsion particles are non-uniform and coalescence of the emulsion particles occurs immediately after preparation. The appearance appears somewhat rough even when observed visually.
1: Component (C) leaks into the external phase (aqueous phase), or emulsified particles are not formed, resulting in separation into an oil phase and an aqueous phase, and the appearance appears heterogeneous even when observed visually.

(3) Feel of use (non-stickiness upon application, ease of application of makeup immediately after application, and lack of shine due to sebum 3 hours after application)
A use test was conducted by 10 expert panelists for evaluating cosmetics for the oil-in-water emulsion cosmetics shown in Tables 1 to 4. Each expert panelist used each cosmetic and gave a score on a 5-point scale based on the following evaluation criteria for "absence of stickiness upon application,""ease of makeup application immediately after application," and "absence of shine due to sebum 3 hours after application," and the average score for each cosmetic was calculated from the total scores of the 10 expert panelists. The average scores for each evaluation are shown in Tables 1 to 4, respectively.
The higher the average value, the better the effect. If the average value exceeds 4.0, it is very good. If the average value is 4.0 or less and more than 3.0, it is good. If the average value is 3.0 or less and more than 2.0, it is slightly poor. If the average value is 2.0 or less, it is poor.
Regarding "how well the makeup applied immediately after application", each oil-in-water emulsion cosmetic was applied to the skin, and then foundation was applied on top of that, and the quality of the makeup applied was evaluated. Regarding "the lack of shine due to sebum 3 hours after application", each oil-in-water emulsion cosmetic was applied to the skin, and then foundation was applied on top of that, and the lack of shine due to sebum 3 hours after application was evaluated.
[Evaluation Criteria]
5: Good 4: Fairly good 3: Average 2: Fairly bad 1: Bad

Details of the components used in Tables 1 to 4 are shown below.
*1: DSM "PARSOL 1789"
*2: "UVINUL A PLUS" manufactured by BASF
*3: BASF "UVINUL T-150"
*4: BASF "UVINUL M40"
*5: "Mosacare A440" manufactured by UFC CORPORATION
*6: "TINOSORB S" manufactured by BASF
*7: "KF-96A-6cs" manufactured by Shin-Etsu Chemical Co., Ltd.
*8: BASF "UVINUL MC80"
*9: "SEPIGEL 305" manufactured by SEPPIC (polyacrylamide, active content 40% by mass)
* 10: SEPPIC's "SIMULGEL EG" ((acryloyldimethyltaurate Na / acrylate Na) copolymer, active content 37.5% by mass)
* 11: "SEPINOV EMT 10" manufactured by SEPPIC ((acryloyldimethyltaurate Na / hydroxyethyl acrylate) copolymer, active content 89.3% by mass),
*12: Clariant "Aristoflex AVC" ((acryloyldimethyltaurate ammonium / vinylpyrrolidone) copolymer, active content 100% by mass)
*13: "PEMULEN TR-1" manufactured by Lubrizol Advanced Materials
* 14: Dimethicone-treated zinc oxide fine particles C1 obtained in Preparation Example 1
*15: Methylhydrogenpolysiloxane-treated zinc oxide fine particles C2 obtained in Preparation Example 2
*16: Triethoxycaprylylsilane-treated zinc oxide fine particles C3 obtained in Preparation Example 3
*17: Dimethicone-treated titanium oxide fine particle C4 obtained in Preparation Example 4
*18: Sakai Chemical Industry Co., Ltd. "STR-100W-LP" (average primary particle diameter 10 nm)
*19: Sakai Chemical Industry Co., Ltd. "STR-100W-OTS" (average primary particle diameter 10 nm)
*20: "Fine particle titanium oxide MT-N1" (average primary particle diameter 7 nm) manufactured by Teika Corporation
*21: "DOWSIL AMS-C30 COSMETIC WAX" (alkyl-modified (C30) silicone) manufactured by Dow Toray Co., Ltd.

Tables 1 to 4 show that the oil-in-water emulsion cosmetics according to the examples of the present invention have superior UV protection capabilities, excellent emulsion stability, are less sticky when applied, have good makeup application, and suppress shine caused by sebum, compared to the oil-in-water emulsion cosmetics of the comparative examples.

Claims (10)

An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B) , (C) , and (D) :
Component (A1): A water-insoluble organic UV absorber that is solid at 25°C. Component (A2): A liquid oil solution Component (B): An acrylamide polymer Component (C): A hydrophobically treated fine particle metal oxide
Component (D): Polyhydric alcohol
the mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.25 or more and 1.8 or less;
An oil-in-water emulsion cosmetic in which the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less of the total amount of the oil-in-water emulsion cosmetic (excluding oil-in-water emulsion cosmetics containing a polyoxyethylene alkyl ether or polyoxyethylene alkenyl ether having an alkyl or alkenyl group with 20 to 24 carbon atoms and an average number of moles of ethylene oxide added of 1.5 to 4, and a phospholipid) . An oil-in-water emulsion cosmetic comprising the following components (A1), (A2), (B), (C), and (D):
Component (A1): A water-insoluble organic ultraviolet absorber that is solid at 25°C
Component (A2): Liquid oil
Component (B): Acrylamide-based polymer
Component (C): Hydrophobically treated fine metal oxide particles
Component (D): Polyhydric alcohol
the mass ratio [(C)/(A1+A2)] of the content of component (C) to the total content of components (A1) and (A2) is 0.25 or more and 1.8 or less;
the total content of 2-ethylhexyl paramethoxycinnamate and octocrylene as component (A2) is 2 mass% or less in the total amount of the oil-in-water emulsion cosmetic;
An oil-in-water emulsion cosmetic, comprising component (D) in an amount of 3% by mass or more and 5% by mass or less. The oil-in-water emulsion cosmetic according to claim 1 or 2, wherein the fine particle metal oxide of component (C) is at least one selected from the group consisting of fine particle zinc oxide and fine particle titanium oxide. The oil-in-water emulsion cosmetic according to any one of claims 1 to 3, wherein the hydrophobic treatment of component (C) is one or more treatments selected from the group consisting of silicone treatment, alkylalkoxysilane treatment, and fatty acid treatment. The oil-in-water emulsion cosmetic according to any one of claims 1 to 4, wherein the hydrophobic treatment of component (C) is at least one selected from the group consisting of silicone treatment using at least one selected from the group consisting of methylhydrogenpolysiloxane and dimethylsiloxane/methylhydrogensiloxane copolymer as a surface treatment agent, alkylalkoxysilane treatment, and fatty acid treatment. The oil-in-water emulsion cosmetic according to any one of claims 1 to 5, wherein the content of component (C) is 3% by mass or more and 30% by mass or less. The oil-in-water emulsion cosmetic according to any one of claims 1 to 6, wherein component (A2) contains one or more oils selected from the group consisting of ester oils and silicone oils. The oil-in-water emulsion cosmetic according to any one of claims 1 to 7, wherein component (A1) is one or more selected from the group consisting of 4-tert-butyl-4'-methoxydibenzoylmethane, 2-(4-diethylamino-2-hydroxybenzoyl)hexyl benzoate, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 2-hydroxy-4-methoxybenzophenone, drometrizole trisiloxane, and 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine. The oil-in-water emulsion cosmetic according to any one of claims 1 to 8, wherein component (B) is at least one selected from the group consisting of a homopolymer of acrylamide, and copolymers containing structural units derived from at least one acrylamide monomer selected from the group consisting of acrylamide and acryloyldimethyltaurate, and salts thereof. The oil-in-water emulsion cosmetic according to any one of claims 1 to 9, which is used for sunscreen purposes.