Oil-in-water emulsion cosmetics

Abstract

To provide cosmetics that have an excellent infrared protection effect and have a unique and fresh feeling of use.SOLUTION: Provided is an oil-in-water emulsified cosmetic containing ingredients (a)-(d): (a) a metal oxide particle having an average particle size of 500 to 1500 nm and having a surface hydrophobically treated; (b) a hydrophobically modified alkylcellulose; (c) an aqueous phase thickener; and (d) an oil content, at this time, the metal oxide particle being dispersed in the oil, and the content of nonionic surfactants with an HLB value of 10 or more being less than 1.0 mass%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an oil-in-water emulsion cosmetic, and more particularly to an oil-in-water emulsion cosmetic for infrared protection. [Background technology]

[0002] 2. Description of the Related Art Conventionally, ultraviolet ray protective cosmetics have been known from the viewpoint of protecting the skin against sunlight.

[0003] For example, Patent Document 1 discloses an oil-in-water emulsion cosmetic that contains an ultraviolet absorbing agent and an ultraviolet scattering agent, and has a high ultraviolet protection function (SPF) while also having a unique, refreshing feel when used. The oil-in-water emulsion cosmetic is characterized in that it contains (A) 0.05 to 1 mass % of a hydrophobically modified alkyl cellulose; (B) 5 to 40 mass % of an oil content; (C) 2.5 to 30 mass % of an ultraviolet scattering agent having a hydrophobic surface; and (D) an aqueous phase thickener with low salt resistance, and in which the ultraviolet scattering agent (C) is dispersed in the oil phase.

[0004] On the other hand, in recent years, health consciousness has increased, and there is a demand for cosmetics that can reduce the heat of sunlight and prevent photoaging of the skin by blocking not only ultraviolet rays (wavelength: approximately 290 to 400 nm) but also infrared rays (wavelength: approximately 750 nm to 1 mm).

[0005] For example, Patent Document 2 discloses a heat-shielding cosmetic that has an ultraviolet blocking effect while improving the infrared heat-shielding effect, and is characterized in that titanium oxide (A) having an average particle size of 5 to 100 nm and titanium oxide (B) having an average particle size of 300 to 3000 nm are blended in a ratio of (A):(B) = 1:9 to 9:1 (weight ratio). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2015-120682 A [Patent Document 2] JP 2013-194041 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, for example, the heat-shielding cosmetic composition disclosed in Patent Document 2 contains a large amount of nonionic surfactant, which makes it difficult to achieve a fresh feel when used.

[0008] The present invention is intended to improve the above-mentioned circumstances, and has an object to provide a cosmetic composition which has an excellent infrared protection effect and a unique, fresh feel when used. [Means for solving the problem]

[0009] The present invention which achieves the above object is as follows.

[0010] <Aspect 1> Contains the following components (a) to (d): (a) metal oxide particles having an average particle size of 500 to 1500 nm and having a hydrophobic surface; (b) hydrophobically modified alkylcellulose; (c) an aqueous phase thickener, and (d) oil, the metal oxide particles are dispersed in the oil; and The content of nonionic surfactants with an HLB value of 10 or more is less than 1.0% by mass. Oil-in-water emulsion cosmetic. <Aspect 2> The cosmetic preparation according to aspect 1, further comprising (e) polyhydroxystearic acid. <Aspect 3> The content of the metal oxide particles is 1.0% by mass or more and 30.0% by mass or less, The content of the hydrophobically modified alkyl cellulose is 0.05% by mass or more and 1.0% by mass or less, The content of the aqueous phase thickener is 0.05% by mass or more and 3.0% by mass or less, and The oil content is 5.0% by mass or more and 40.0% by mass or less. A cosmetic preparation according to aspect 1 or 2. <Aspect 4> The cosmetic preparation according to any one of Aspects 1 to 3, wherein the metal oxide particles are titanium oxide. <Aspect 5> The cosmetic preparation according to any one of Aspects 1 to 4, wherein the hydrophobically modified alkyl cellulose is hydrophobically modified hydroxypropyl methyl cellulose. Aspect 6 A cosmetic preparation according to any one of aspects 1 to 5, wherein the aqueous phase thickener comprises a vinyl polymer or an acrylic polymer. Aspect 7 A cosmetic preparation according to any one of Aspects 1 to 6, wherein 55% by mass or more of the oil component is polar oil. <Aspect 8> (f) The cosmetic preparation according to any one of Aspects 1 to 7, further comprising an ionic surfactant. <Aspect 9> (g) The cosmetic preparation according to any one of Aspects 1 to 8, further comprising a water-soluble polyether-modified silicone wax. Aspect 10 10. The cosmetic preparation according to any one of Aspects 1 to 9, which is an infrared protective cosmetic preparation. Effect of the Invention

[0011] According to the present invention, it is possible to provide a cosmetic preparation which has an excellent infrared protection effect and a unique, fresh feel when used.

[0012] In the present invention, the term "unique, fresh feel when used" means that when the cosmetic is applied to the skin with the fingers or the like, the cosmetic feels as if the viscosity suddenly decreases and the cosmetic crumbles, and at the same time gives an extremely fresh feel as it spreads over the skin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the preferred embodiments. Note that the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[0014] <Oil-in-water emulsion cosmetics> The oil-in-water emulsion cosmetic of the present invention (hereinafter, also simply referred to as "the cosmetic of the present invention") is Contains the following components (a) to (d): (a) metal oxide particles having an average particle size of 500 to 1500 nm and having a hydrophobic surface; (b) hydrophobically modified alkylcellulose; (c) an aqueous phase thickener, and (d) oil, Metal oxide particles are dispersed in an oil, and The content of nonionic surfactants having an HLB value of 10 or more is less than 1.0% by mass.

[0015] The cosmetic composition of the present invention contains specific constituent components and has a content of nonionic surfactants with an HLB value of 10 or more kept to less than 1.0 mass %, thereby enabling the cosmetic composition to exhibit the effects of the present invention, i.e., to have excellent infrared protection effects and a unique, refreshing feel when used.

[0016] The cosmetic of the above-mentioned Patent Document 1 is mainly intended to block ultraviolet rays, and uses an ultraviolet scattering agent with a relatively small average particle size. For this reason, Patent Document 1 discloses that a hydrophobically modified alkyl cellulose with a relatively weak emulsifying action is used instead of a nonionic surfactant with a strong emulsifying action, and an oil containing an ultraviolet scattering agent with a relatively small average particle size is emulsified to obtain an oil-in-water emulsion cosmetic in which a hydrophobic powder is dispersed in the internal oil phase.

[0017] On the other hand, it is difficult to emulsify oil containing metal oxide particles with a relatively large average particle size, and it is generally known to blend a large amount of a surfactant with a relatively strong emulsifying effect. For example, Patent Document 2 discloses that a large amount of a nonionic surfactant with a content of 1% by mass or more is used as an emulsifier to obtain an oil-in-water emulsion cosmetic in which a hydrophobic powder is dispersed in the internal oil phase.

[0018] On the other hand, the inventors of the present invention have not been bound by the conventional stereotypes mentioned above, and through their intensive research, have succeeded in obtaining an oil-in-water emulsion cosmetic in which a hydrophobic powder is dispersed in the internal oil phase by using a hydrophobically modified alkyl cellulose having an appropriate emulsifying power, even in a system of "oil containing metal oxide particles having a relatively large average particle size," which was previously considered difficult to emulsify, thereby arriving at the present invention.

[0019] Without being limited by theory, this is because when a surfactant with strong emulsifying power (i.e., a nonionic surfactant with an HLB value of 10 or more) is used, a stable interface film can be formed, but the size of the emulsified particles becomes relatively small. Therefore, it is considered that metal oxide particles with a relatively large average particle size become relatively close to the size of the emulsified particles, and are easily detached from the emulsified particles (oil droplets). In contrast, in the present invention, by using a surfactant with a relatively weak emulsifying power such as hydrophobically modified alkyl cellulose, the emulsified particles become relatively large. Therefore, in this case, it is considered that metal oxide particles with a relatively large average particle size are less likely to be detached from the emulsified particles.

[0020] In this way, by limiting the content of nonionic surfactants with an HLB value of 10 or more to less than 1.0 mass%, the present invention not only makes it possible to obtain an oil-in-water emulsion cosmetic in which a hydrophobic powder is dispersed in a stable internal oil phase without making the emulsion particle size smaller than desired, but also makes it possible to suppress the sticky feel that results from a large amount of nonionic surfactants, thereby achieving a unique, refreshing feel when used.

[0021] In the cosmetic of the present invention, the content of nonionic surfactants having an HLB value of 10 or more may be 0.9% by mass or less, 0.8% by mass or less, 0.7% by mass or less, 0.6% by mass or less, 0.5% by mass or less, 0.4% by mass or less, 0.3% by mass or less, 0.2% by mass or less, 0.1% by mass or less, or 0% by mass.

[0022] (a) Metal oxide particles The metal oxide particles contained in the cosmetic of the present invention (hereinafter also simply referred to as "metal oxide particles of the present invention") have an average particle diameter of 500 to 1500 nm and are metal oxide particles that have been surface-treated to be hydrophobic.

[0023] The metal oxide particles of the present invention have an average particle diameter of 500 to 1500 nm, and therefore have the function of blocking infrared rays, particularly near infrared rays.

[0024] In the present invention, the "average particle size" refers to the average particle size of primary particles.

[0025] In the present invention, the average particle size can be calculated as the diameter of a circle equivalent to the projected area of ​​primary particles observed by SEM or TEM.

[0026] The metal oxide particles of the present invention are surface-hydrophobized. Here, the hydrophobization treatment may be carried out using a known surface treatment agent that is hydrophobized, and examples thereof include fluorine compound treatment, silicone treatment, silicone resin treatment, pendant treatment, silane coupling agent treatment, titanium coupling agent treatment, oil treatment, N-acylated lysine treatment, polyacrylic acid treatment, isostearic acid treatment, metal soap treatment, amino acid treatment, inorganic compound treatment, plasma treatment, mechanochemical treatment, silane compound treatment, silazane compound treatment, etc. Among these treatments, from the viewpoint of dispersion stability, etc., treatment with silicone or silicone resin, treatment with silane compound or silazane compound, and isostearic acid treatment are preferred.

[0027] The metal oxide particles of the present invention may be surface-hydrophobically treated titanium oxide, surface-hydrophobically treated zinc oxide, surface-hydrophobically treated cerium oxide, or a mixture thereof, etc., but from the viewpoint of improving the shielding effect in the infrared region, surface-hydrophobically treated titanium oxide is preferred.

[0028] The shape of the metal oxide particles of the present invention is not particularly limited, and examples thereof include spherical, plate-like, rod-like, spindle-like, needle-like, and irregular shapes.

[0029] As the metal oxide particles of the present invention, commercially available ones may be used.

[0030] Furthermore, as the metal oxide particles of the present invention, commercially available products in which metal oxide particles are dispersed in a dispersant such as polyhydroxystearic acid may be used.

[0031] In the cosmetic of the present invention, the content of the metal oxide particles is not particularly limited, and may be, for example, 1.0% by mass or more, 1.5% by mass or more, 2.0% by mass or more, 2.5% by mass or more, 3.0% by mass or more, 3.5% by mass or more, 4.0% by mass or more, 4.5% by mass or more, 5.0% by mass or more, 5.5% by mass or more, 6.0% by mass or more, 6.5% by mass or more, 7.0% by mass or more, 7.5% by mass or more, 8.0% by mass or more, 8.5% by mass or more, 9.0% by mass or more, 9.5% by mass or more, or 10.0% by mass or more, or 30.0% by mass or less, 20.0% by mass or less, or 10.0% by mass or less. In addition, when the metal oxide particles are in a state of being dispersed in a dispersant such as polyhydroxystearic acid, the content of the metal oxide particles referred to here refers to the content of the solid content in the cosmetic of the present invention.

[0032] (b) Hydrophobically modified alkyl cellulose The hydrophobically modified alkyl cellulose contained in the cosmetic composition of the present invention does not belong to the category of "nonionic surfactants having an HLB value of 10 or more" and is generally classified as a "polymeric surfactant."

[0033] In the present invention, the hydrophobically modified alkyl cellulose refers to an alkyl cellulose that has been hydrophobically modified with an alkyl group having a carbon number of 14 to 22. This hydrophobically modified alkyl cellulose is a compound in which a long-chain alkyl group, which is a hydrophobic group, has been introduced into a water-soluble cellulose ether derivative, and is represented by the following general formula (I).

[0034] [ka] [In the formula, R may be the same or different and is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a -[CH2CH(CH3)O] group, m A is one or more groups selected from -H (wherein m is an integer of 1 to 5, preferably 1 to 3), -CH2CH2OH, and -CH2CH(OH)CH2OR' (wherein R' is an alkyl group having 14 to 22 carbon atoms), but must include the -CH2CH(OH)CH2OR' group. A is also a -(CH2) q -(q is an integer of 1 to 3, preferably 1), and n is an integer of 100 to 10,000, preferably 500 to 5,000.]

[0035] The method for producing the hydrophobically modified alkyl cellulose of formula (I) generally involves the production of a water-soluble cellulose ether derivative as a base, specifically, methyl cellulose (wherein R is a hydrogen atom or a methyl group), ethyl cellulose (wherein R is a hydrogen atom or an ethyl group), propyl cellulose (wherein R is a hydrogen atom or a propyl group), butyl cellulose (wherein R is a hydrogen atom or a butyl group), hydroxypropyl cellulose [wherein R is a hydrogen atom or a hydroxypropyl group (group -[CHCH(CHO)] m The above-mentioned copolymer can be obtained by contacting a compound for introducing a long-chain alkyl group having 14 to 22 carbon atoms, specifically a long-chain alkyl glycidyl ether of the following formula (II), with a hydroxypropyl methylcellulose (R is a hydrogen atom, a methyl group, or a hydroxypropyl group (same as above)) or the like in the presence of an alkali catalyst.

[0036] [ka] [In the formula, R' is an alkyl group having 14 to 22 carbon atoms.]

[0037] The content of the group -CH2CH(OH)CH2OR' introduced into the hydrophobically modified alkyl cellulose of the present invention is preferably about 0.1 to 5.0% by mass based on the total amount of the hydrophobically modified alkyl cellulose. In order to achieve such a content, the molar ratio, reaction time, type of alkali catalyst, etc., of the reaction between the water-soluble cellulose ester derivative and the long-chain alkyl glycidyl ether may be appropriately selected for production. After the reaction, the reaction product may be subjected to a purification step such as neutralization, filtration, washing, drying, and sieving.

[0038] Among the above water-soluble cellulose ether derivatives, it is particularly preferable to select hydroxypropylmethylcellulose (wherein R in formula (I) is a hydrogen atom, a methyl group, a -[CHCH(CH)O] group, m H, and the group -CH2CH(OH)CH2OR', and q of the group A is 1, and A is a methylene group.

[0039] Furthermore, R' in the long-chain alkyl glycidyl ether of formula (II) is an alkyl group having 14 to 22 carbon atoms, preferably an alkyl group having 14 to 20 carbon atoms, and more preferably a stearyl group having 18 carbon atoms (-C 18 H 37 If the alkyl group R' has less than 14 carbon atoms or more than 23 carbon atoms, the emulsion stability of the resulting hydrophobically modified alkyl cellulose becomes insufficient.

[0040] The weight average molecular weight of the hydrophobically modified alkyl cellulose is preferably from 100,000 to 1,000,000, more preferably from 300,000 to 800,000, and further preferably from 550,000 to 750,000.

[0041] In the present invention, as the hydrophobically modified alkyl cellulose, it is preferable to use hydrophobically modified hydroxypropyl methylcellulose (hydrophobized hydroxypropyl methylcellulose), more specifically, stearoxy hydroxypropyl cellulose.In addition, as the hydrophobically modified alkyl cellulose, commercially available products can also be used, for example, Sangelose 90L (display name: hydrophobized hydroxypropyl methylcellulose; manufactured by Daido Chemical Industry Co., Ltd.), Natrosol Plus 330cs (manufactured by Ashland Co., Ltd.), Polysurf 67cs (manufactured by Ashland Co., Ltd.), etc., but are not limited thereto.

[0042] In the cosmetic preparation of the present invention, the content of hydrophobically modified alkyl cellulose is not particularly limited and may be, for example, 0.05% by mass or more, 0.10% by mass or more, 0.15% by mass or more, 0.20% by mass or more, 0.25% by mass or more, 0.30% by mass or more, 0.35% by mass or more, 0.40% by mass or more, 0.45% by mass or more, or 0.50% by mass or more, and may be 1.0% by mass or less, 0.80% by mass or less, 0.50% by mass or less, or 0.30% by mass or less.

[0043] (c) Aqueous Phase Thickener The aqueous phase thickener contained in the cosmetic of the present invention is a thickener that has the function of thickening the aqueous phase, and may be one that reduces the viscosity in the presence of electrolytes at concentrations in the range generally used in cosmetics. In the present invention, such aqueous phase thickeners that reduce the viscosity due to an increase in the electrolyte concentration are also referred to as "aqueous phase thickeners with low salt tolerance". Such thickeners with low salt tolerance are selected from water-soluble thickeners that have been conventionally used in cosmetics and the like for the purpose of adjusting the viscosity of the aqueous phase.

[0044] Specific examples include vinyl polymers such as polyvinyl alcohol, polyvinyl acetate, polyvinyl methyl ether, polyvinylpyrrolidone, vinylpyrrolidone and vinyl acetate copolymers, and carboxyvinyl polymers; and acrylic polymers such as sodium polyacrylate, polyethyl acrylate, polyacrylic alkanolamine, alkyl methacrylate and dimethylaminoethyl methacrylate copolymers, poly2-acrylamido-2-methylpropanesulfonic acid, polymethacryloyloxytrimethylammonium, (ammonium acryloyldimethyltaurate / VP) copolymer, and dimethylacrylamide / Na acryloyldimethyltaurate crosspolymer, but are not limited to these.

[0045] However, among thickeners with low salt tolerance, thickeners that form water-swellable microgels in the aqueous phase and thicken due to friction between swollen microgel particles are preferred, as they can further suppress stickiness when the cosmetic is applied to the skin, compared to thickeners that thicken due to entanglement of polymer chains. This is because the hydrophobically modified alkyl cellulose blended as an emulsifier also has a thickening effect due to entanglement of polymer chains, and further blending a thickener that thickens by the same mechanism may promote the thickening effect and cause stickiness.

[0046] In the cosmetic of the present invention, the content of the aqueous phase thickener is not particularly limited, and may be, for example, 0.05% by mass or more, 0.07% by mass or more, 0.10% by mass or more, 0.15% by mass or more, 0.17% by mass or more, 0.20% by mass or more, 0.25% by mass or more, 0.27% by mass or more, 0.275% by mass or more, 0.30% by mass or more, 0.35% by mass or more, 0.37% by mass or more, 0.40% by mass or more, 0.45% by mass or more, 0.47% by mass or more, or 0.50% by mass or more, and may be 3.0% by mass or less, 2.0% by mass or less, or 1.0% by mass or less.

[0047] (d) Oil content The oil contained in the cosmetic of the present invention can be one or more types selected from oily components commonly used in cosmetics and the like.

[0048] In the cosmetic of the present invention, the oil content is not particularly limited and may be, for example, 5.0 mass% or more, 6.0 mass% or more, 7.0 mass% or more, 8.0 mass% or more, 9.0 mass% or more, 10.0 mass% or more, 11.0 mass% or more, 12.0 mass% or more, 13.0 mass% or more, 14.0 mass% or more, 15.0 mass% or more, or 16.0 mass% or more, and may be 40.0 mass% or less, 30.0 mass% or less, or 20.0 mass% or less.

[0049] In the present invention, the oil content preferably contains polar oil.For example, in the cosmetic of the present invention, when the oil content is 55% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, the emulsion stability can be further improved.In addition, the upper limit of the proportion of polar oil in the oil content is not particularly limited, and for example, polar oil may be 90% or more, or 100% of the oil content may be polar oil.

[0050] In the present invention, the "polar oil" is not particularly limited as long as it is an oil with high polarity among oils commonly used in cosmetics. For example, oils with a relative dielectric constant of about 5 or more, preferably about 10 or more, are preferably used.

[0051] Representative examples of polar oils include ester oils and ultraviolet absorbers. In addition, since the cosmetic contains a larger amount of polar oil than conventional cosmetics, it is possible to stably blend, for example, highly polar fragrances.

[0052] (Ester oil) Specific examples of ester oils that can be used as polar oils in the present invention include tripropylene glycol dineopentanoate, isononyl isononanoate, isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, cholesteryl 12-hydroxystearate, cetyl ethylhexanoate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid esters, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, glycerin di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, tetra- Pentaerythrityl 2-ethylhexanoate, triethylhexanoin (tri-2-ethylhexanoic acid glycerin), trioctanoic acid glycerin, triisopalmitic acid glycerin, triisostearate trimethylolpropane, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, trimyristate glycerin, tri-2-heptylundecanoic acid glyceride, castor oil fatty acid methyl ester, oleyl oleate, acetoglyceride, palmitic acid Examples of the oleic acid esters include, but are not limited to, 2-heptylundecyl oleate, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, and triethyl citrate.

[0053] (UV absorber) In the present invention, specific examples of ultraviolet absorbers that can be used as polar oils include, but are not limited to, benzoic acid derivatives, salicylic acid derivatives, cinnamic acid derivatives, dibenzoylmethane derivatives, β,β-diphenylacrylate derivatives, benzophenone derivatives, benzylidene camphor derivatives, phenylbenzimidazole derivatives, triazine derivatives, phenylbenzotriazole derivatives, anthranil derivatives, imidazoline derivatives, benzalmalonate derivatives, 4,4-diarylbutadiene derivatives, etc. Some specific examples and trade names of these are illustrated below.

[0054] Examples of benzoic acid derivatives include, but are not limited to, ethyl para-aminobenzoate (PABA), ethyl-dihydroxypropyl PABA, ethylhexyl-dimethyl PABA (e.g., "Escarol 507"; manufactured by ISP), glyceryl PABA, PEG-25-PABA (e.g., "Uvinal P25"; manufactured by BASF), and diethylaminohydroxybenzoylhexylbenzoate (e.g., "Uvinal A Plus"), etc.

[0055] Salicylic acid derivatives include, but are not limited to, homosalate (e.g., "Eusolex HMS"; Rona / EM Industries), ethylhexyl salicylate (e.g., "NeoHeliopan OS"; Herman & Reimer), dipropylene glycol salicylate (e.g., "Dipsal"; Skel), and TEA salicylate (e.g., "NeoHeliopan TS"; Herman & Reimer).

[0056] Examples of cinnamic acid derivatives include, but are not limited to, ethylhexyl methoxycinnamate (e.g., Parsol MCX; manufactured by Hoffmann-La Roche), isopropyl methoxycinnamate, isoamyl methoxycinnamate (e.g., Neo-Heliopan E1000; manufactured by Herman & Reimer), cinnoxate, DEA methoxycinnamate, diisopropyl methylcinnamate, glyceryl-ethylhexanoate-dimethoxycinnamate, and di-(2-ethylhexyl)-4'-methoxybenzalmalonate.

[0057] Dibenzoylmethane derivatives include, but are not limited to, 4-tert-butyl-4'-methoxydibenzoylmethane (eg, "Parsol 1789"), and the like.

[0058] Examples of β,β-diphenylacrylate derivatives include, but are not limited to, octocrylene (eg, "Uvinal N539" manufactured by BASF).

[0059] Benzophenone derivatives include, but are not limited to, benzophenone-1 (e.g., "Uvinal 400"; manufactured by BASF), benzophenone-2 (e.g., "Uvinal D50"; manufactured by BASF), benzophenone-3 or oxybenzone (e.g., "Uvinal M40"; manufactured by BASF), benzophenone-4 (e.g., "Uvinal MS40"; manufactured by BASF), benzophenone-5, benzophenone-6 (e.g., "Helisorb 11"; manufactured by Norquay), benzophenone-8 (e.g., "Spectra-Sorb UV-24"; manufactured by American Cyanamid), benzophenone-9 (e.g., "Uvinal DS-49"; manufactured by BASF), and benzophenone-12.

[0060] Examples of benzylidene camphor derivatives include, but are not limited to, 3-benzylidene camphor (e.g., "Mexoryl SD"; manufactured by Symex), 4-methylbenzylidene camphor, benzylidene camphorsulfonic acid (e.g., "Mexoryl SL"; manufactured by Symex), benzalkonium camphor methosulfate (e.g., "Mexoryl SO"; manufactured by Symex), terephthalide discamphorsulfonic acid (e.g., "Mexoryl SX"; manufactured by Symex), and polyacrylamide methyl benzylidene camphor (e.g., "Mexoryl SW"; manufactured by Symex).

[0061] Examples of phenylbenzimidazole derivatives include, but are not limited to, phenylbenzimidazole sulfonic acid (e.g., "Eutholex 232"; manufactured by Merck) and disodium phenyldibenzimidazole tetrasulfonate (e.g., "Neo-Heliopan AP"; manufactured by Herman & Reimer).

[0062] Examples of triazine derivatives include, but are not limited to, anisotriazine (e.g., "Tinosorb S"; manufactured by Ciba Specialty Chemicals), ethylhexyl triazone (e.g., "Uvinal T150"; manufactured by BASF), diethylhexylbutamidotriazone (e.g., "Uvasorb HEB"; manufactured by Sigma 3V), and 2,4,6-tris(diisobutyl-4'-aminobenzalmalonate)-s-triazine.

[0063] Examples of phenylbenzotriazole derivatives include, but are not limited to, drometrizole trisiloxane (e.g., "Silatrizole" manufactured by Rhodia-Chemie), and methylene bis(benzotriazolyl tetramethylbutylphenol) (e.g., "Tinosorb M" manufactured by Ciba Specialty Chemicals).

[0064] Examples of anthranil derivatives include, but are not limited to, menthyl anthranilate (for example, "Neo-Heliopan MA"; manufactured by Herman & Reimer).

[0065] Imidazoline derivatives include, but are not limited to, ethylhexyl dimethoxybenzylidene dioxoimidazoline propionate, and the like.

[0066] Examples of benzalmalonate derivatives include, but are not limited to, polyorganosiloxanes having benzalmalonate functional groups (for example, polysilicone-15; "Parsol SLX"; manufactured by DSM Nutrition Japan).

[0067] Examples of 4,4-diarylbutadiene derivatives include, but are not limited to, 1,1-dicarboxy(2,2'-dimethylpropyl)-4,4-diphenylbutadiene and the like.

[0068] <Other Ingredients> In addition to the essential components (a) to (d) described above, the cosmetic of the present invention may further contain other components within the scope of not impairing the effects of the present invention. The other components will be described below by way of example.

[0069] ((e) Polyhydroxystearic acid) The cosmetic preparation of the present invention may further contain polyhydroxystearic acid. Polyhydroxystearic acid is preferred from the viewpoint of having the effect of uniformly dispersing the metal oxide particles of the present invention in oil.

[0070] Polyhydroxystearic acid is a compound in which hydroxystearic acid is oligomerized by forming an ester bond, and commercially available products include, for example, HS Oligomer 600 (manufactured by Toyokuni Oil Mills Co., Ltd.) and Salacos HS-6C (manufactured by Nisshin Oillio Co., Ltd.), which can be used. The degree of polymerization of polyhydroxystearic acid is not particularly limited and may be, for example, 4 to 8.

[0071] In the cosmetic preparation of the present invention, when polyhydroxystearic acid is contained, the content of polyhydroxystearic acid may be, for example, 0.01 to 3.0 mass %, 0.05 to 2.0 mass %, or 0.10 to 1.0 mass %.

[0072] (f) Ionic Surfactants The cosmetic preparation of the present invention may further contain an ionic surfactant. The ionic surfactant is preferred from the viewpoint of preventing the emulsion particles from coalescing due to electrostatic repulsion.

[0073] Ionic surfactants are surfactants that dissociate into ions when dissolved in water, and are specifically classified into anionic surfactants, cationic surfactants, amphoteric surfactants, and the like.

[0074] Examples of ionic surfactants include anionic surfactants such as N-stearoyl-N-methyl taurine, sodium N-stearoyl-N-methyl taurine, disodium N-stearoyl-L-glutamate, sodium N-stearoyl-L-glutamate, sodium polyoxyethylene lauryl ether acetate, polyoxyethylene lauryl ether acetate triethanolamine, sodium laurate taurine, sodium lauroyl methyl taurine, and triethanolamine laurate; cationic surfactants such as stearyl dimethylamine oxide and stearyl trimethylammonium chloride; and amphoteric surfactants such as lauryl dimethyl betaine and lauryl dimethyl amino acetate betaine, but are not limited to these.

[0075] In the cosmetic preparation of the present invention, when an ionic surfactant is contained, the content of the ionic surfactant may be, for example, 0.01 to 2.0 mass %, 0.05 to 1.0 mass %, or 0.10 to 0.50 mass %.

[0076] (Other Surfactants) With regard to nonionic surfactants ("nonionic surfactants"), the cosmetic preparation of the present invention may contain nonionic surfactants with an HLB value of less than 10, so long as the content of nonionic surfactants with an HLB value of 10 or more is less than 1.0 mass%.

[0077] Examples of nonionic surfactants with an HLB value of less than 10 include, but are not limited to, bisbutyldimethicone polyglyceryl-3 (HLB value: 0.5), PEG-10 dimethicone (HLB value: 2.0), and PEG-9 polydimethylsiloxyethyl dimethicone (HLB value: 4.0).

[0078] When the cosmetic preparation of the present invention further contains a nonionic surfactant having an HLB value of less than 10, the content thereof may be, for example, 0.01 to 2.0% by mass, or 0.05 to 1.0% by mass.

[0079] In addition to the above-mentioned surfactants, for example, polymeric surfactants or natural surfactants may be further blended into the cosmetic composition of the present invention, so long as they do not impair the effects of the present invention.

[0080] ((g) Water-soluble polyether modified silicone wax) The cosmetic of the present invention may further contain a water-soluble polyether-modified silicone wax. The water-soluble polyether-modified silicone wax is preferred from the viewpoint of making the cosmetic of the present invention non-sticky, further improving the emulsion stability, and providing a refreshing emulsion.

[0081] Examples of the water-soluble polyether-modified silicone wax include, but are not limited to, bisPEG-18 methyl ether dimethyl silane, bisPEG-15 methyl ether dimethicone, PEG-32 methyl ether dimethicone, and PEG-17 dimethicone.

[0082] In addition, the water-soluble polyether-modified silicone wax can be obtained from commercial products, and examples thereof include, but are not limited to, CosmeticWax 2501 (manufactured by Dow Corning Toray Co., Ltd., bis-PEG-18 methyl ether dimethylsilane, melting point 36 to 42°C), DMC 6038 (manufactured by Wacker, bis-PEG-15 methyl ether dimethicone, melting point approximately 30°C), KF-6004 (manufactured by Shin-Etsu Chemical Co., Ltd., PEG-32 methyl ether dimethicone, melting point 45°C), and Silsoft (registered trademark) 895 (manufactured by MOMENTIVE, PEG-17 dimethicone).

[0083] When the cosmetic preparation of the present invention contains a water-soluble polyether-modified silicone wax, the content of the water-soluble polyether-modified silicone wax may be, for example, 0.1 to 20.0 mass %, 0.5 to 15.0 mass %, or 1.0 to 10.0 mass %.

[0084] ((h) Cooling agent) The cosmetic of the present invention may further contain a cooling agent. The cooling agent is preferable from the viewpoint of enhancing a feeling of coolness.

[0085] The cooling agent may be one or more selected from the group consisting of menthol, peppermint oil, l-menthyl glyceryl ether, menthyl lactate, camphor, isopulegol, bornol, cineole menthone, spearmint, peppermint, menthyl malonate, glycosyl-mono-menthyl-O-acetate, 3-L-menthoxypropane-1,2-diol, and 1-menthyl-3-hydroxybutyrate.

[0086] In the cosmetic preparation of the present invention, when a water freshening agent is contained, the content of the water freshening agent may be, for example, 0.1 to 10.0 mass %, 0.5 to 10.0 mass %, or 1.0 to 5.0 mass %.

[0087] In addition to the above-mentioned "other components," the cosmetic composition of the present invention may contain, for example, glycols such as propylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, diethylene glycol, triethylene glycol, and polyethylene glycol; glycerins such as glycerin, diglycerin, and polyglycerin; sugar alcohols such as sorbitol, mannitol, maltitol, xylitol, and erythritol; sugars such as fructose, glucose, galactose, maltose, lactose, and trehalose; natural pigments such as chlorophyll and β-carotene; plant-based polymers such as gum arabic, gum tragacanth, galactan, guar gum, carob gum, karaya gum, gellan gum, and carrageenan; microbial polymers such as xanthan gum, dextran, succinoglucan, and pullulan; and animal-based polymers such as collagen, casein, albumin, and gelatin. the like; starch-based polymers such as carboxymethyl starch and methyl hydroxypropyl starch; cellulose-based polymers such as methyl cellulose, ethyl cellulose, methyl hydroxypropyl cellulose, hydroxyethyl cellulose, sodium cellulose sulfate, hydroxypropyl cellulose, sodium carboxymethyl cellulose, and crystalline cellulose; alginic acid-based polymers such as sodium alginate and propylene glycol alginate; other thickeners; vitamins such as magnesium ascorbyl phosphate, ascorbyl glucoside, vitamin B6 hydrochloride, and pantothenyl ethyl ether; pharmaceutical agents such as bactericides, anti-inflammatory agents, preservatives, plant extracts, and amino acids; lower alcohols such as ethanol and isopropyl alcohol; aromatic alcohols such as phenoxyethanol and benzyl alcohol; or silica, and other various ingredients that are commonly incorporated into cosmetics.

[0088] The cosmetic of the present invention can be prepared according to a method commonly used for oil-in-water emulsion cosmetics, i.e., by mixing the aqueous phase component and the oil phase component separately, and emulsifying the aqueous phase component by adding the oil phase component while stirring the aqueous phase component.

[0089] The cosmetic of the present invention may have an emulsion particle size of, but is not limited to, 7.5 μm on average and approximately 20 μm at maximum. The emulsion particle size can be determined, for example, by using a microscope to comprehensively determine the size of the emulsion particles (measured with a micrometer) and their distribution state (uniformity of particles in the field of view of the microscope) with the naked eye.

[0090] The cosmetic of the present invention can exhibit the above-mentioned effects of the present invention, and therefore may be an infrared protective cosmetic. EXAMPLES

[0091] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these. In the following, the contents are shown in mass % unless otherwise specified.

[0092] Cosmetics of the Examples and Comparative Examples were prepared according to the formulations shown in Table 1 below. The stability, infrared cut rate, usability, and emulsion particle size of each obtained cosmetic were evaluated according to the following criteria, and the results are shown in Table 2.

[0093] <Stability> Each of the cosmetic compositions obtained in the Examples and Comparative Examples was filled into two screw tubes (50 ml) and allowed to stand for two weeks in a thermostatic chamber at 0° C. or 50° C. Before and after standing, the change in viscosity was measured using a rotational viscometer (Vismetron rotational viscometer), and the emulsion particles and appearance were observed: "Evaluation Criteria" "A": No decrease in viscosity was observed at either temperature level of 0°C or 50°C, and there were no problems with the emulsion particles or appearance. "B": At any temperature level, a slight decrease in viscosity, an increase in emulsified particles, or a change in appearance was observed. "C": Protrusion of metal oxide particles was observed at either temperature level.

[0094] <Infrared blocking rate> Each cosmetic material obtained in the examples and comparative examples was applied to a PMMA (polymethyl methacrylate resin) substrate (HD6 manufactured by HelioScreen) and dried for 15 minutes to prepare a measurement sample. A PMMA substrate without any coating was used as a control sample. The transmittance of the measurement sample and the control sample was measured at 1500 nm using a spectrophotometer (UV-3600 manufactured by Shimadzu Corporation, integrating sphere mode). During the measurement, the coated surface of the PMMA substrate was attached to the outer edge of the opening of the integrating sphere using double-sided tape. The transmittance of the measurement sample divided by the transmittance of the control sample was determined as the transmittance, and (100% - transmittance) was determined as the infrared cut rate (%).

[0095] <Feel of use> The cosmetic compositions obtained in the Examples and Comparative Examples were evaluated by three expert panelists for their texture in use, based on the following criteria: "A": Excellent freshness. "B": Excellent freshness. "C": Less fresh.

[0096] <Emulsification particle size> Using a microscope, the size of the emulsion particles (measured with a micrometer) and their distribution (uniformity of particles in the field of view of the microscope) were comprehensively judged with the naked eye to determine the emulsion particle size of each cosmetic obtained in the Examples and Comparative Examples. In Table 2, the expression "1-10 (20)" means that the majority of the emulsion particles had a diameter in the range of about 1-10 μm, with a small number of emulsion particles up to about 20 μm being present. The same applies to other expressions.

[0097] [Table 1]

[0098] [Table 2]

[0099] As is clear from Table 1, it was found that the cosmetics of Examples 1 to 9 have an excellent infrared protection effect and also have a unique, fresh feel when used.

[0100] Moreover, the cosmetic compositions of Examples 1 to 6 have better stability than the cosmetic compositions of Examples 7 to 9, which is believed to be due to the inclusion of polyhydroxystearic acid. The cosmetic compositions of Examples 7 to 9 further contain surfactants such as sorbitan sesquiisostearate, isostearic acid, and bisbutyldimethicone polyglyceryl-3, instead of polyhydroxystearic acid. These surfactants function as powder dispersants, but are analyzed to be somewhat inferior to polyhydroxystearic acid in terms of dispersibility, particularly for large metal oxide particles.

Claims

1. Contains the following components (a) to (d): (a) metal oxide particles having an average particle size of 500 to 1,500 nm and having a hydrophobic surface; (b) hydrophobically modified alkyl cellulose; (c) an aqueous phase thickener, and (d) oil, the metal oxide particles are dispersed in the oil; and The content of nonionic surfactants having an HLB value of 10 or more is less than 1.0% by mass. Oil-in-water emulsion cosmetic.

2. The cosmetic preparation according to claim 1, further comprising (e) polyhydroxystearic acid.

3. The content of the metal oxide particles is 1.0% by mass or more and 30.0% by mass or less, The content of the hydrophobically modified alkyl cellulose is 0.05% by mass or more and 1.0% by mass or less, The content of the aqueous phase thickener is 0.05% by mass or more and 3.0% by mass or less, and The content of the oil is 5.0% by mass or more and 40.0% by mass or less. The cosmetic preparation according to claim 1 or 2.

4. The cosmetic preparation according to any one of claims 1 to 3, wherein the metal oxide particles are titanium oxide.

5. The cosmetic preparation according to any one of claims 1 to 4, wherein the hydrophobically modified alkyl cellulose is hydrophobically modified hydroxypropyl methyl cellulose.

6. The cosmetic preparation according to any one of claims 1 to 5, wherein the aqueous phase thickener comprises a vinyl polymer or an acrylic polymer.

7. The cosmetic preparation according to any one of claims 1 to 6, wherein 55% by mass or more of the oil component is a polar oil.

8. The cosmetic preparation according to any one of claims 1 to 7, further comprising (f) an ionic surfactant.

9. The cosmetic preparation according to any one of claims 1 to 8, further comprising (g) a water-soluble polyether-modified silicone wax.

10. The cosmetic according to any one of claims 1 to 9, which is an infrared ray protective cosmetic.

Images