Oil-in-water emulsion cosmetics

Abstract

To provide an oil-in-water emulsion cosmetic having excellent UV protection effect.SOLUTION: An oil-in-water emulsion cosmetic contains (A) an ultraviolet absorber, (B) a white pigment, (C) a skin-whitening agent and / or anti-inflammatory agent, and (D) a UV scattering agent. The content of the (A) ultraviolet absorber is 10 mass% or less relative to the total amount of the oil-in-water emulsion cosmetic. The content of an UVA absorbent in the (A) ultraviolet absorber is 25 mass% or more relative to the total amount of the (A) ultraviolet absorber.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Protecting skin from the harmful effects of ultraviolet rays is an important issue in skin care and body care, and various UV protection cosmetics have been developed to minimize the adverse effects of ultraviolet rays on the skin. Sunscreen cosmetics, one type of UV protection cosmetic, contain ultraviolet absorbers and the like to block UVA and UVB rays from reaching the skin, thereby protecting the skin from the harmful effects of ultraviolet rays (see, for example, Non-Patent Document 1).

[0003] On the other hand, in order to maintain good usability, such as stickiness, of the cosmetic, the content of the ultraviolet absorber should be set as small as possible. However, if the content of the ultraviolet absorber in the cosmetic is set to a small amount, it is difficult to achieve a high ultraviolet protection effect.

[0004] In the past, to achieve a high UV protection effect, zinc (powder) and the like were blended in high concentrations, but this sometimes caused stability problems, such as the zinc agglomerating in the cosmetic. Furthermore, while oil-in-water emulsion cosmetics that have UV protection effects have been known (see, for example, Patent Document 1), no oil-in-water emulsion cosmetics with a reduced content of UV absorbers are known at all.

[0005] Under these circumstances, there is a demand for the development of highly stable oil-in-water emulsion cosmetics with a reduced content of ultraviolet absorbers. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2017 / 188319 [Non-patent literature]

[0007] [Non-Patent Document 1] "New Cosmetics Science", 2nd edition, edited by Takeo Mitsui, 2001, Nanzando Publishing, pp. 497-504 Summary of the Invention

[0008] The present inventors have surprisingly found that, even when the content of an ultraviolet absorber in an oil-in-water emulsion cosmetic is 10% by mass or less and a white pigment, a whitening agent, and / or an anti-inflammatory agent is also contained, a highly stable cosmetic can be achieved by setting the content of a UVA absorber in the ultraviolet absorber to a certain percentage or more and adding a white pigment and an ultraviolet scattering agent to form an oil-in-water emulsion cosmetic. The present invention is based on these findings.

[0009] Furthermore, while it is important to add new functions to increase consumer purchasing power, it has now been discovered that the inclusion of a whitening agent and / or an anti-inflammatory agent in a cosmetic reduces the UV protection effect. On the other hand, it has been discovered that the oil-in-water emulsion cosmetic of the present invention, which contains a certain percentage or more of UVA absorber in the UV absorber and also contains a white pigment and an UV scattering agent, can also solve this problem.

[0010] The present invention discloses an oil-in-water emulsion cosmetic comprising (A) an ultraviolet absorber, (B) a white pigment, (C) a whitening agent and / or an anti-inflammatory agent, and (D) an ultraviolet scattering agent, wherein the content of the (A) ultraviolet absorber is 10% by mass or less, relative to the total amount of the oil-in-water emulsion cosmetic, and the content of the UVA absorber in the (A) ultraviolet absorber is 25% by mass or more, relative to the total amount of the (A) ultraviolet absorber.

[0011] According to the present invention, the following inventions are provided. (1)(A) an ultraviolet absorber; (B) white pigment, (C) a skin lightening agent and / or an anti-inflammatory agent, and (D) UV scattering agent An oil-in-water emulsion cosmetic comprising: The content of the (A) ultraviolet absorber is 10% by mass or less relative to the total amount of the oil-in-water emulsion cosmetic, and The content of the UVA absorber in the (A) ultraviolet absorber is 25 mass% or more based on the total amount of the (A) ultraviolet absorber. Oil-in-water emulsion cosmetics. (2) The oil-in-water emulsion cosmetic according to (1), wherein the content of the UVA absorber in the ultraviolet absorber (A) is 2.5% by mass or more relative to the total amount of the oil-in-water emulsion cosmetic. (3) The oil-in-water emulsion cosmetic according to (1) or (2), wherein the UVA absorber comprises one or more selected from the group consisting of t-butyl methoxydibenzoylmethane, diethylamino hydroxybenzoyl hexyl benzoate, and bis-ethylhexyloxyphenol methoxyphenyl triazine. (4) The oil-in-water emulsion cosmetic according to any one of (1) to (3), wherein the (B) white pigment contains pigment-grade titanium oxide. (5) The oil-in-water emulsion cosmetic according to (4), wherein the pigment-grade titanium oxide has an average particle size of 200 nm or more. (6) The oil-in-water emulsion cosmetic according to any one of (1) to (5), wherein the (C) whitening agent comprises one or more selected from the group consisting of L-ascorbic acid and derivatives thereof, tranexamic acid and derivatives thereof, alkoxysalicylic acid and derivatives thereof, and nicotinic acid and derivatives thereof. (7) The oil-in-water emulsion cosmetic according to any one of (1) to (6), wherein the (C) anti-inflammatory agent includes glycyrrhizinic acid and its derivatives. (8) The oil-in-water emulsion cosmetic according to any one of (1) to (7), further comprising (E) a nonionic surfactant. (9) The oil-in-water emulsion cosmetic according to (8), wherein the nonionic surfactant (E) comprises polyoxyethylene hydrogenated castor oil.

[0012] The use of the oil-in-water emulsion cosmetic of the present invention is advantageous in that it is possible to provide an oil-in-water emulsion cosmetic that has high stability even when the content of the UV absorber is kept to 10% by mass or less relative to the total amount of the cosmetic and when a white pigment, a whitening agent, and / or an anti-inflammatory agent is contained. Furthermore, the use of the cosmetic of the present invention is also advantageous in that it maintains high UV protection efficacy even when the cosmetic contains a whitening agent and / or an anti-inflammatory agent, which reduces the UV protection efficacy. Specific Description of the Invention

[0013] The present invention provides (A) an ultraviolet absorber, (B) white pigment, (C) a skin lightening agent and / or an anti-inflammatory agent, and (D) UV scattering agent An oil-in-water emulsion cosmetic comprising: The content of the (A) ultraviolet absorber is 10% by mass or less relative to the total amount of the oil-in-water emulsion cosmetic, and The content of the UVA absorber in the (A) ultraviolet absorber is 25 mass% or more based on the total amount of the (A) ultraviolet absorber. It is an oil-in-water emulsion cosmetic.

[0014] (A) UV absorber The ultraviolet absorber (A) (hereinafter sometimes simply referred to as "ingredient A") incorporated into the oil-in-water emulsion cosmetic of the present invention can be at least one selected from ultraviolet absorbers that have conventionally been incorporated into sunscreen cosmetics.

[0015] The ultraviolet absorber contained in the oil-in-water emulsion cosmetic of the present invention preferably contains at least a UVA absorber and also a UVB absorber. Ultraviolet rays are classified into long-wavelength ultraviolet rays (UVA) with wavelengths of 320 to 400 nm, medium-wavelength ultraviolet rays (UVB) with wavelengths of 290 to 320 nm, and short-wavelength ultraviolet rays (UVC) with wavelengths of 290 nm or less, and the ultraviolet absorber contained in the oil-in-water emulsion cosmetic of the present invention is preferred because it can absorb ultraviolet rays in a wide range from UVA to UVB.

[0016] The ultraviolet absorber contained in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, but specific examples include ultraviolet absorbers such as 2-ethylhexyl paramethoxycinnamate, 2,4-bis-{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)1,3,5-triazine, octocrylene, dimethicodiethylbenzalmalonate, polysilicon-15, t-butylmethoxydibenzoylmethane, ethylhexyl triazone, diethylaminohydroxybenzoylhexyl benzoate, bisethylhexyloxyphenol methoxyphenyl triazine, oxybenzone-3, methylenebisbenzotriazolyltetramethylbutylphenol, phenylbenzimidazole sulfonic acid, homosalate, ethylhexyl salicylate, ethylhexyl methoxycinnamate, and ethylhexyl triazone.

[0017] The UVA absorber among the ultraviolet absorbers contained in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, but specific examples include methylenebisbenzotriazolyltetramethylbutylphenol, t-butylmethoxydibenzoylmethane, diethylaminohydroxybenzoylhexylbenzoate, or bis-ethylhexyloxyphenol methoxyphenyl triazine, and preferably contains one or more selected from the group consisting of t-butylmethoxydibenzoylmethane, diethylaminohydroxybenzoylhexylbenzoate, and bis-ethylhexyloxyphenol methoxyphenyl triazine, and more preferably contains at least bis-ethylhexyloxyphenol methoxyphenyl triazine, or contains bis-ethylhexyloxyphenol methoxyphenyl triazine and diethylaminohydroxybenzoyl hexyl benzoate.

[0018] The UVB absorber among the ultraviolet absorbers contained in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, but specific examples include ethylhexyl methoxycinnamate, ethylhexyl triazone, octocrylene, dimethicodiethyl benzalmalonate, polysilicon-15, oxybenzone-3, phenylbenzimidazole sulfonic acid, homosalate, and ethylhexyl salicylate, and preferably includes ethylhexyl methoxycinnamate and / or ethylhexyl triazone.

[0019] The content of the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention is 10% by mass or less, preferably 5 to 10% by mass, more preferably 6 to 10% by mass, and even more preferably 8 to 10% by mass, relative to the total amount of the oil-in-water emulsion cosmetic. By reducing the content of the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention, it is possible to further maintain good usability of the cosmetic, such as stickiness.

[0020] The content of UVA absorber in the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention is 25% by mass or more, preferably 35% by mass or more, and more preferably 35 to 60% by mass, based on the total amount of ultraviolet absorber. By making the content of UVA absorber in the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention 35% by mass or more, based on the total amount of ultraviolet absorber, it is possible to further improve the ultraviolet protection effect.

[0021] Furthermore, the content of UVA absorber in the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention is preferably 2.5% by mass or more, more preferably 3.5% by mass or more, and even more preferably 3.5 to 6% by mass, relative to the total amount of the oil-in-water emulsion cosmetic. By making the content of UVA absorber in the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention 3.5% by mass or more, relative to the total amount of the oil-in-water emulsion cosmetic, it is possible to further improve the ultraviolet protection effect. The content of UVB absorber in the ultraviolet absorber in the oil-in-water emulsion cosmetic of the present invention is the amount obtained by subtracting the content of UVA absorber from the total content of ultraviolet absorbers.

[0022] (B) White pigment The (B) white pigment (hereinafter sometimes simply referred to as "ingredient B") contained in the oil-in-water emulsion cosmetic according to the present invention can be selected from white pigments that are commonly incorporated into external skin preparations such as cosmetics, and examples include titanium oxide, photochromic titanium oxide (titanium dioxide formed by sintering iron oxide), reduced zinc oxide, etc. These white pigments may be surface-treated.

[0023] The average particle size of the white pigment is preferably a size that exhibits a high light scattering effect due to Mie scattering or geometrical optical scattering, for example, an average particle size of about so-called pigment-grade (preferably 200 nm or more, more preferably 200 to 500 nm). Among white pigments, it is preferable to contain titanium oxide, which has excellent shielding effect. In a preferred embodiment, the white pigment contained in the oil-in-water emulsion cosmetic according to the present invention contains pigment-grade titanium oxide. In this specification, the average particle size is a value calculated as the arithmetic mean of the major and minor axes of particles measured using a transmission electron microscope photograph, laser scattering / diffraction method, or the like. The shape of the pigment-grade titanium oxide is not particularly limited and may be spherical, elliptical, crushed, or the like.

[0024] When the (B) white pigment contained in the oil-in-water emulsion cosmetic according to the present invention is titanium oxide, the titanium oxide may be a commercially available product, and specific examples thereof include Typepaque A-100 (anatase type, surface untreated, particle size (average particle size) 0.4 μm, manufactured by Ishihara Sangyo Kaisha), Chronos KA-10 (anatase type, untreated, particle size 0.3 to 0.5 μm, manufactured by Titan Kogyo Co., Ltd.), Chronos KA-15 (anatase type, untreated, particle size 0.3 to 0.5 μm, manufactured by Titan Kogyo Co., Ltd.), Chronos KA-20 (anatase type, aluminum oxide treated, particle size 0.3 to 0.5 μm, manufactured by Titan Kogyo Co., Ltd.), and Chronos KA-15 (anatase type, untreated, particle size 0.3 to 0.5 μm, manufactured by Titan Kogyo Co., Ltd.). LONOS KA-30 (anatase type, untreated, particle size 0.2-0.4 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KA-35 (anatase type, untreated, particle size 0.2-0.4 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KA-80 (anatase type, aluminum oxide treated, silicon dioxide treated, particle size 0.3-0.5 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KR-310 (rutile type, untreated, particle size 0.3-0.5 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KR-380 (rutile type, aluminum oxide treated, silicon dioxide treated, particle size 0.3-0.5 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS LONOS KR-460 (rutile type, aluminum oxide treatment, particle size 0.2-0.4 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KR-480 (rutile type, aluminum oxide treatment, silicon dioxide treatment, particle size 0.2-0.4 μm, manufactured by Titanium Kogyo Co., Ltd.), KRONOS KR-270 (rutile type, zinc oxide treatment, aluminum oxide treatment, particle size 0.2-0.4 μm, manufactured by Titanium Kogyo Co., Ltd.), Titanix JR-301 (rutile type, aluminum oxide treatment, particle size 0.3 μm, manufactured by Teika Co., Ltd.), Titanix JR-403 (rutile type, aluminum oxide treatment, silicon dioxide treatment, particle size Titanix JR-405 (rutile type, aluminum oxide treated, particle size 0.21 μm, manufactured by Teika Corporation), Titanix JR-600A (rutile type, aluminum oxide treated, particle size 0.25 μm, manufactured by Teika Corporation), Titanix JR-605 (rutile type, aluminum oxide treated, particle size 0.25 μm, manufactured by Teika Corporation), Titanix JR-600E (rutile type, aluminum oxide treated, particle size 0.27 μm, manufactured by Teika Corporation), Titanix JR-603 (rutile type, aluminum oxide treated, zirconium oxide treated, particle size 0.28 μm, manufactured by Teika Corporation), Titanix JR-805 (rutile type, aluminum oxide, silicon dioxide treated, particle size 0.29 μm, manufactured by Teika Corporation), Titanix JR-806 (rutile type, aluminum oxide treated, silicon dioxide treated, particle size 0.25 μm, manufactured by Teika Corporation), Titanix JR-701 (rutile type, aluminum oxide treated, silicon dioxide treated, zinc oxide treated, particle size 0.27 μm, manufactured by Teika Corporation), Titanix JRNC (rutile type, aluminum oxide treated, silicon dioxide treated, zirconium oxide treated, manufactured by Teika Corporation), Titanix JR-800 (rutile type, aluminum oxide treated Examples include: Titanix JR (rutile type, untreated, particle size 0.27 μm, manufactured by Teika Corporation), Titanix JA-1 (anatase type, untreated, particle size 0.18 μm, manufactured by Teika Corporation), Titanix JA-C (anatase type, untreated, particle size 0.18 μm, manufactured by Teika Corporation), Titanix JA-3 (anatase type, untreated, particle size 0.18 μm, manufactured by Teika Corporation), Titanix JA-4 (anatase type, aluminum oxide treated, particle size 0.18 μm, manufactured by Teika Corporation), and Titanix JA-5 (anatase type, untreated, particle size 0.18 μm, manufactured by Teika Corporation). However, the present invention is not limited to these examples.

[0025] The content of the white pigment in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, but is preferably 0.5 to 3 mass% and more preferably 1 to 2.5 mass% relative to the total amount of the oil-in-water emulsion cosmetic. By making the content of the white pigment in the oil-in-water emulsion cosmetic of the present invention 1 mass% or more, it is possible to further improve the UV protection effect.

[0026] (C) Whitening and / or anti-inflammatory agents The (C) whitening agent (hereinafter sometimes simply referred to as "ingredient C-1") and / or anti-inflammatory agent (hereinafter sometimes simply referred to as "ingredient C-2") contained in the oil-in-water emulsion cosmetic of the present invention may be any of those conventionally used in external skin preparations such as cosmetics.

[0027] The whitening agent that may be contained in the oil-in-water emulsion cosmetic according to the present invention is not particularly limited, but preferably contains one or more selected from the group consisting of L-ascorbic acid and its derivatives, tranexamic acid and its derivatives, alkoxysalicylic acid and its derivatives, and nicotinic acid and its derivatives, and particularly preferably contains tranexamic acid and its derivatives.

[0028] Examples of derivatives of L-ascorbic acid include sodium L-ascorbate, magnesium L-ascorbate, L-ascorbic acid glucoside, 2-O-ethyl-L-ascorbic acid, and 3-O-ethyl-L-ascorbic acid, with L-ascorbic acid glucoside being particularly preferred.

[0029] Examples of derivatives of tranexamic acid include trans-4-(trans-aminomethylcyclohexanecarbonyl)aminomethylcyclohexanecarboxylic acid hydrochloride, 4-(trans-aminomethylcyclohexanecarboxylic acid 4'-hydroxyphenyl ester, 2-(trans-4-aminomethylcyclohexylcarbonyloxy)-5-hydroxybenzoic acid, trans-4-aminomethylcyclohexanecarboxylic acid methylamide, trans-4-(p-methoxybenzoyl)aminomethylcyclohexanecarboxylic acid, and trans-4-guanidinomethylcyclohexanecarboxylic acid.

[0030] Examples of alkoxysalicylic acids and derivatives thereof include 3-methoxysalicylic acid, 3-ethoxysalicylic acid, 4-methoxysalicylic acid, 4-ethoxysalicylic acid, 4-propoxysalicylic acid, 4-isopropoxysalicylic acid, 4-butoxysalicylic acid, 5-methoxysalicylic acid, 5-ethoxysalicylic acid, 5-propoxysalicylic acid, and salts of these alkoxysalicylic acids. Of these, potassium 4-methoxysalicylate is particularly preferred.

[0031] Examples of the derivatives of nicotinic acid include benzyl nicotinate, nicotinamide, and dl-α-tocopherol nicotinate, with nicotinamide being particularly preferred.

[0032] Anti-inflammatory agents that may be contained in the oil-in-water emulsion cosmetic according to the present invention are not particularly limited, but examples include glycyrrhizinic acid and derivatives thereof, glycyrrhetinic acid and derivatives thereof, salicylic acid and derivatives thereof, and ufenamate, and among these, it is preferable to include glycyrrhizinic acid and derivatives thereof.

[0033] Examples of derivatives of glycyrrhizinic acid include dipotassium glycyrrhizinate and monoammonium glycyrrhizinate, with dipotassium glycyrrhizinate being particularly preferred.

[0034] The content of the whitening agent and / or anti-inflammatory agent in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, but is preferably 0.05 to 5 mass %, and more preferably 0.1 to 3 mass %, relative to the total amount of the oil-in-water emulsion cosmetic.

[0035] (D) UV scattering agent The (D) UV scattering agent (hereinafter sometimes referred to simply as "ingredient D") contained in the oil-in-water emulsion cosmetic of the present invention is not particularly limited, as long as it is a powder used as a UV scattering agent in the field of cosmetics. Specific examples include one or more selected from zinc oxide, barium sulfate, iron oxide, talc, mica, sericite, kaolin, titanium dioxide, iron blue, chromium oxide, chromium hydroxide, silica, cerium oxide, etc., and it is preferable that it contains zinc oxide. Furthermore, when the average particle size of the (B) white pigment contained in the oil-in-water emulsion cosmetic of the present invention is 200 nm or more, the (D) UV scattering agent contained in the oil-in-water emulsion cosmetic of the present invention may contain titanium oxide having an average particle size of less than 100 nm.

[0036] By subjecting the surface of the ultraviolet scattering agent to hydrophobic treatment, the dispersibility in oil and water resistance are improved, and in the present invention, a hydrophobic treated ultraviolet scattering agent is preferably used.

[0037] Examples of surface treatment methods include silicone treatment with methylhydrogenpolysiloxane, methylpolysiloxane, etc.; silica treatment with silica, hydrated silica, etc.; alkyldextrin treatment with dextrin palmitate, etc.; distearyldimethylammonium chloride treatment; alkylsilane treatment with octyltriethoxysilane, etc.; fluorine treatment with perfluoroalkyl phosphate ester, perfluoroalcohol, etc.; amino acid treatment with N-acylglutamic acid, etc.; lecithin treatment; metal soap treatment with aluminum stearate, magnesium isostearate, etc.; fatty acid treatment; and alkyl phosphate ester treatment.

[0038] The ultraviolet scattering agent used in the present invention is not particularly limited, but in general, the average primary particle size is preferably 100 nm or less, more preferably 80 nm or less. If the average primary particle size is significantly greater than 100 nm, it tends to cause whitening or residual white.

[0039] The average primary particle size in the present invention is a value determined as the arithmetic mean of the major and minor axes of particles from, for example, a transmission electron micrograph.

[0040] The particle shape of the ultraviolet scattering agent is not particularly limited, and may be in the form of primary particles or may form secondary aggregates. Furthermore, the shape, such as spherical, elliptical, or crushed, is also not particularly limited.

[0041] The content of the UV scattering agent in the oil-in-water emulsion cosmetic of the present invention is 5 to 15% by mass, and more preferably 10 to 14% by mass, based on the total amount of the oil-in-water emulsion cosmetic.

[0042] (E) Nonionic surfactants The nonionic surfactant (E) (hereinafter sometimes simply referred to as "ingredient E") that may be contained in the oil-in-water emulsion cosmetic according to the present invention includes one or more nonionic surfactants selected from those that have traditionally been used in oil-in-water emulsion cosmetics, and among these, those with an HLB value of 6 or higher are preferably included.

[0043] In terms of formulation stability, the nonionic surfactant used in the present invention preferably contains polyoxyethylene hydrogenated castor oil. Specific examples of polyoxyethylene hydrogenated castor oil include PEG-10 hydrogenated castor oil, PEG-20 hydrogenated castor oil, PEG-25 hydrogenated castor oil, PEG-30 hydrogenated castor oil, PEG-40 hydrogenated castor oil, PEG-50 hydrogenated castor oil, PEG-60 hydrogenated castor oil, PEG-80 hydrogenated castor oil, and PEG-100 hydrogenated castor oil. On the other hand, when polyoxyethylene hydrogenated castor oil is not contained, it is preferable to use a nonionic surfactant with an HLB of 8 or more, preferably 10 or more, and more preferably 12 or more.

[0044] The content of the nonionic surfactant in the oil-in-water emulsion cosmetic of the present invention is 0.5 to 5 mass %, more preferably 0.8 to 3 mass %, based on the total amount of the oil-in-water emulsion cosmetic.

[0045] (F) Oil phase thickener The oil phase thickener (F) (hereinafter, sometimes simply referred to as "ingredient F") that may be contained in the oil-in-water emulsion cosmetic according to the present invention is a substance that can adjust the viscosity of the oil phase, and preferably includes one or more selected from the group consisting of dextrin fatty acid esters, sucrose fatty acid esters, organically modified clay minerals, and solid or semi-solid hydrocarbon oils.

[0046] The dextrin fatty acid ester is an ester of dextrin or reduced dextrin with a higher fatty acid, and any dextrin commonly used in cosmetics can be used without any particular limitation. It is preferable to use dextrin or reduced dextrin with an average degree of glycopolymerization of 3 to 100. Furthermore, it is preferable to use saturated fatty acids having 8 to 22 carbon atoms as the constituent fatty acids of the dextrin fatty acid ester. Specific examples include dextrin palmitate, dextrin oleate, dextrin stearate, dextrin myristate, and dextrin (palmitate / 2-ethylhexanoate).

[0047] The sucrose fatty acid esters that can be used preferably include those in which the fatty acids are linear or branched, saturated or unsaturated, and have 12 to 22 carbon atoms. Specific examples include sucrose caprylate, sucrose caprate, sucrose laurate, sucrose myristate, sucrose palmitate, sucrose stearate, sucrose oleate, and sucrose erucate.

[0048] The solid or semi-solid hydrocarbon oil is a hydrocarbon that is solid or semi-solid at room temperature (25°C), and specific examples include petrolatum, hydrogenated palm oil, hydrogenated castor oil (castor wax), hydrogenated palm kernel oil, hydrogenated castor oil, hydrogenated peanut oil, hydrogenated rapeseed seed oil, hydrogenated camellia oil, hydrogenated soybean oil, hydrogenated olive oil, hydrogenated macadamia nut oil, hydrogenated sunflower oil, hydrogenated wheat germ oil, hydrogenated rice germ oil, hydrogenated rice bran oil, hydrogenated cottonseed oil, hydrogenated avocado oil, and waxes.

[0049] Organically modified clay minerals are a type of colloidal hydrous aluminum silicate with a three-layer structure, and a typical example is a clay mineral represented by the following general formula (1) modified with a quaternary ammonium salt-type cationic surfactant. (X,Y) 2-3 (Si,Al)O 10 (OH)2Z 1 / 3 nH2O (1) (However, X=Al, Fe(III), Mn(III), Cr(III), Y=Mg, Fe(II), Ni, Zn, Li, Z=K, Na, Ca)

[0050] Specific examples include dimethyl distearyl ammonium hectorite (disteardimonium hectorite), dimethyl alkyl ammonium hectorite, benzyl dimethyl stearyl ammonium hectorite, distearyl dimethyl ammonium chloride-treated magnesium aluminum silicate, etc. Preferred commercially available products include Bentone 27 (benzyl dimethyl stearyl ammonium chloride-treated hectorite: manufactured by Elementis Japan Co., Ltd.) and Bentone 38 (distearyl dimethyl ammonium chloride-treated hectorite: manufactured by Elementis Japan Co., Ltd.).

[0051] The fatty acid to be used may be one that is solid at room temperature, such as myristic acid, palmitic acid, stearic acid, behenic acid, etc. Furthermore, the salts of the fatty acids may include calcium salts, magnesium salts, aluminum salts, etc. of these fatty acids.

[0052] The oil phase thickener in the oil-in-water emulsion cosmetic of the present invention is present in an amount of 0.5 to 3 mass %, more preferably 0.5 to 2 mass %, based on the total amount of the oil-in-water emulsion cosmetic.

[0053] Other optional components include water-soluble or oil-soluble film-forming agents. The incorporation of a film-forming agent can further enhance the resistance of (A) the ultraviolet absorber and (B) the white pigment to leakage and rubbing off by clothing, etc. However, the amount of the film-forming agent incorporated is preferably within a range that does not impair the film-forming feel (ease of use) or detergency.

[0054] The film-forming agent is not particularly limited as long as it is one that is commonly used in cosmetics, and specific examples thereof include PVP-based film-forming agents such as polyvinylpyrrolidone (PVP), PVP / dimethylaminoethyl methacrylate copolymer, PVP / eicosene copolymer, PVP / ethyl methacrylate / methacrylic acid copolymer, PVP / hexadecene copolymer, PVP / VA copolymer, PVP / vinyl acetate / itaconic acid copolymer, and styrene / PVP copolymer; ethyl acrylate / acrylic acid amide / acrylic acid copolymer, ethyl acrylate / butyl acrylate copolymer, ethyl acrylate / ethyl methacrylate copolymer, ethyl acrylate / methacrylic acid copolymer, ethyl acrylate / methyl methacrylate copolymer, octyl acrylate / vinyl acetate copolymer, octyl acrylate / styrene copolymer, butyl acrylate / vinyl acetate copolymer, butyl acrylate / ethyl hydroxymethacrylate copolymer, acrylic Examples of suitable coating agents include acrylic acid-based coating agents such as butyl acrylate / methyl methacrylate copolymer, methoxyethyl acrylate / hydroxyethyl acrylate / butyl acrylate copolymer, lauryl acrylate / vinyl acetate copolymer, polyethyl acrylate, polybutyl acrylate, and polystyrene-acrylic acid resin; vinyl acetate-based coating agents such as polyvinyl acetate; methacrylic acid-based coating agents such as polymethyl methacrylate, methyl methacrylate / butyl acrylate / octylic acrylate, and diethyl vinyl pyrrolidone sulfate / N,N'-dimethylamino methacrylic acid copolymer; vinyl methyl ether-based coating agents such as vinyl methyl ether / ethyl maleate copolymer and vinyl methyl ether / butyl maleate copolymer; styrene-based coating agents such as styrene / methylstyrene / indene copolymer; alkyd resin-based coating agents such as cyclohexane-based alkyd resin; and silicone resin-based coating agents such as trimethylsiloxysilicate.

[0055] Other optional ingredients include ingredients commonly used in cosmetics, such as moisturizers, antioxidants, oil-based active agents, surfactants, aqueous phase thickeners (e.g., stearoxyhydroxypropylmethylcellulose, succinoglycan, (dimethylacrylamide / sodium acryloyldimethyltaurate) crosspolymer, etc.), usable powders (excluding those that have been hydrophobized), coloring materials other than white pigments, aqueous active agents, etc.

[0056] The oil-in-water emulsion cosmetic of the present invention can be produced by a conventional method, for example, by dissolving an optional aqueous thickener in an aqueous component (including a nonionic surfactant), optionally adding a surfactant to a portion of the oil component in which the oil thickener has been dissolved to dissolve or disperse an ultraviolet scattering agent, adding this to the aqueous component and emulsifying it using a homomixer or the like, and finally adding the remaining oil component and powder and stirring and mixing (shear force may be applied as desired during stirring).

[0057] The oil-in-water emulsion cosmetic of the present invention can be preferably used, for example, as a sunscreen cream, a sunscreen emulsion, a sunscreen lotion, a foundation with sunscreen effect, a makeup base, and the like. [Example]

[0058] The present invention will be described in detail based on the following examples, but the present invention is not limited to these examples. Contents are expressed in mass % unless otherwise specified.

[0059] Test Example 1 The oil-in-water emulsion cosmetics of Examples 1 to 10 and Comparative Examples 1 to 6 below (see Tables 1 to 3) were evaluated for "UV protection effect" and "emulsion stability." In Tables 1 to 3, "PEG-100 hydrogenated castor oil" and "PEG-60 hydrogenated castor oil" represent nonionic surfactants, "ethylhexyl methoxycinnamate" and "ethylhexyl triazone" represent UVB absorbers, "diethylamino hydroxybenzoyl hexyl benzoate," "bisethylhexyloxyphenol methoxyphenyl triazine," and "t-butyl methoxydibenzoylmethane" represent UVA absorbers, "pigment-grade titanium oxide" (Tipake CR-50, manufactured by Ishihara Sangyo Kaisha, Ltd.) represents a white pigment, "tranexamic acid" represents a whitening agent, and "silica-coated silicone-treated zinc oxide microparticles" represents an UV scattering agent.

[0060] Method for evaluating UV protection effect The UV protection effect of the oil-in-water emulsion cosmetics of Examples 1 to 10 and Comparative Examples 1 to 6 was evaluated according to the following evaluation method. The evaluation results are shown in Tables 4 to 6 below.

[0061] <Measurement of UV protection effect> Each cosmetic (sample) was applied at 2 mg / cm to a measurement plate (S plate) (5 x 5 cm V-groove PMMA (polymethyl methacrylate) plate, SPFMASTER-PA01). 2 The absorbance of the resulting coating was measured using a Hitachi U-3500 model recording spectrophotometer. An uncoated plate was used as a control, and the absorbance (Abs) was calculated using the following formula. The measured values at 290-320 nm (UVB region) (B region) and 320-400 nm (UVA region) (A region) were integrated, and the integrated absorbance values for each and the sum of the integrated absorbance values were calculated. Abs=-log(T / To) T: transmittance of sample, To: transmittance of uncoated sample

[0062] From the integrated absorbance values of the samples thus obtained, the improvement rate of the UV protection power was calculated using the following formula, relative to a sample (reference sample) containing only a UVB absorber as an ultraviolet absorber. [Improvement rate of UV protection (%)] = [integrated absorbance value of sample] / [integrated absorbance value of reference sample] x 100 The calculated improvement rate of UV protection power (Area A boost effect (increase in absorbance), Area B boost effect (increase in absorbance), and total boost effect (total of Area A and Area B) (increase in absorbance)) was evaluated based on the following evaluation criteria.

[0063] <Evaluation criteria> A: UV protection improved by over 110% B: UV protection improvement rate is 105% or more but less than 110% C: UV protection improvement rate is less than 105%

[0064] Emulsion stability evaluation method The oil-in-water emulsion cosmetics of Examples 1 to 10 and Comparative Examples 1 to 6 below (see Tables 1 to 3) were evaluated according to the following evaluation methods and criteria. The evaluation results are shown in Tables 4 to 6 below.

[0065] <Observation of emulsion stability> Each cosmetic sample was stored at 60°C for two weeks, and the presence or absence of separation or sedimentation was visually observed. The measurement results were evaluated according to the following criteria.

[0066] <Evaluation criteria> A: No separation or sedimentation was observed and the product was stable. B: Separation or sedimentation was observed.

[0067] [Table 1]

[0068] [Table 2]

[0069] [Table 3]

[0070] [Table 4]

[0071] [Table 5]

[0072] [Table 6]

[0073] The results in Tables 4 to 6 above demonstrate that oil-in-water emulsion cosmetics containing an ultraviolet absorber, a white pigment, a whitening agent, and an ultraviolet scattering agent, in which the content of the ultraviolet absorber is 10% by mass or less relative to the total amount of the oil-in-water emulsion cosmetic, and the content of the UVA absorber in the ultraviolet absorber is 25% by mass or more relative to the total amount of the ultraviolet absorber, have a high ultraviolet protection effect and high emulsion stability. Furthermore, when tranexamic acid (a skin whitening agent) was removed from the reference sample in Table 1, the integrated absorbance value (including both areas A and B) was found to be approximately 1.27 times higher than the reference sample containing tranexamic acid (a skin whitening agent). In other words, it was found that adding tranexamic acid (a skin whitening agent) to a cosmetic product reduces absorbance and therefore UV protection effectiveness. Furthermore, when the tranexamic acid (skin whitening agent) in the reference sample in Table 1 was replaced with L-ascorbic acid glucoside (skin whitening agent), potassium 4-methoxysalicylate (skin whitening agent), nicotinamide (skin whitening agent), or dipotassium glycyrrhizinate (anti-inflammatory agent) and incorporated into a cosmetic product, the integrated absorbance (including both regions A and B) was found to be approximately 1.02 times (L-ascorbic acid glucoside), approximately 1.21 times (potassium 4-methoxysalicylate), approximately 1.33 times (nicotinamide), and approximately 1.31 times (dipotassium glycyrrhizinate) compared to a cosmetic product containing these whitening agents or anti-inflammatory agents when these whitening agents or anti-inflammatory agents were omitted. In other words, it was found that the addition of whitening agents or anti-inflammatory agents other than tranexamic acid (skin whitening agent) to a cosmetic product also reduces the absorbance and UV protection effect.

Claims

1. (A) an ultraviolet absorber, (B) a white pigment, (C) a whitening agent and / or an anti-inflammatory agent, and (D) UV scattering agent An oil-in-water emulsion cosmetic comprising: the content of the ultraviolet absorber (A) is 10% by mass or less relative to the total amount of the oil-in-water emulsion cosmetic; the content of the UVA absorber in the (A) ultraviolet absorber is 25% by mass or more based on the total amount of the (A) ultraviolet absorber; the content of the (B) white pigment is 0.5 to 3% by mass relative to the total amount of the oil-in-water emulsion cosmetic; The content of the (C) whitening agent and / or anti-inflammatory agent is 0.05 to 5% by mass relative to the total amount of the oil-in-water emulsion cosmetic, and The content of the (D) ultraviolet scattering agent is 5 to 15% by mass relative to the total amount of the oil-in-water emulsion cosmetic. Oil-in-water emulsion cosmetics.

2. 2. The oil-in-water emulsion cosmetic according to claim 1, wherein the content of the UVA absorber in the ultraviolet absorber (A) is 2.5% by mass or more, based on the total amount of the oil-in-water emulsion cosmetic.

3. 3. The oil-in-water emulsion cosmetic according to claim 1, wherein the UVA absorber comprises one or more selected from the group consisting of t-butyl methoxydibenzoylmethane, diethylamino hydroxybenzoyl hexyl benzoate, and bis-ethylhexyloxyphenol methoxyphenyl triazine.

4. The oil-in-water emulsion cosmetic according to any one of claims 1 to 3, wherein the (B) white pigment comprises pigment-grade titanium oxide.

5. 5. The oil-in-water emulsion cosmetic according to claim 4, wherein the pigment-grade titanium oxide has an average particle size of 200 nm or more.

6. 6. The oil-in-water emulsion cosmetic according to claim 1, wherein the (C) skin whitening agent comprises one or more selected from the group consisting of L-ascorbic acid and derivatives thereof, tranexamic acid and derivatives thereof, alkoxysalicylic acid and derivatives thereof, and nicotinic acid and derivatives thereof.

7. The oil-in-water emulsion cosmetic according to any one of claims 1 to 6, wherein the (C) anti-inflammatory agent comprises glycyrrhizinic acid or a derivative thereof.

8. The oil-in-water emulsion cosmetic according to any one of claims 1 to 7, further comprising (E) a nonionic surfactant.

9. The oil-in-water emulsion cosmetic according to claim 8, wherein the nonionic surfactant (E) comprises polyoxyethylene hydrogenated castor oil.

10. The oil-in-water emulsion cosmetic according to any one of claims 1 to 9, wherein the UVA absorber is bis-ethylhexyloxyphenol methoxyphenyl triazine.

11. The oil-in-water emulsion cosmetic according to any one of claims 1 to 10, wherein the content of the UVA absorber in the ultraviolet absorber (A) is 35 to 60 mass% with respect to the total amount of the ultraviolet absorber (A).

12. The oil-in-water emulsion cosmetic according to any one of claims 1 to 11, wherein the (C) skin whitening agent is tranexamic acid or a derivative thereof.

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