Sunscreen cosmetic

Abstract

This sunscreen cosmetic contains components (A), (B), and (C).　(A): 0.1-10 mass% of a polyalkylene glycol derivative represented by formula (I). (B): 2-40 mass% of an ultraviolet protective agent. (C): 0.01-10 mass% of a water soluble thickening agent. (I): Z-{O-(EO)a-(BO)k-H}m (in the formula, Z represents a residue obtained by removing a hydroxyl group from a polyhydric alcohol having three or more carbon atoms and having 3-6 hydroxyl groups, m represents an integer of 3-6, EO represents an oxyethylene group, BO represents an oxybutylene group, and EOs and BOs are bonded in a block-like manner. a represents the average number of added moles of EO, k represents the average number of added moles of BO, a is an integer of 1-50, and k is an integer of 1-50. In addition, the mass proportion of (EO)a with respect to the total 100 parts by mass of (EO)a and (BO)k is 10-75 parts by mass.)

Description

Sunscreen cosmetics

[0001] The present invention relates to a sunscreen cosmetic.

[0002] Some polymer compounds exhibit phase transitions in response to external stimuli such as heat, pH, light, and water, and the development of temperature sensors, separation membranes, adsorbents, drug release agents, water absorbents, water retention agents, humidity control agents, indicator agents, and the like that utilize this phase transition phenomenon is actively underway. Among the polymer compounds described above, those that exhibit phase transitions in response to stimuli are called stimuli-responsive polymers. Living polymers of vinyl ethers containing oxyethylene chains are known as stimuli-responsive polymers that respond to thermal stimuli. These living polymers have a cloud point, and in aqueous solution, they exhibit hydrophilicity below the cloud point and hydrophobicity above the cloud point.

[0003] Patent Document 1 discloses that by using a diblock copolymer of a vinyl ether containing an oxyethylene chain and a vinyl ether containing an azobenzene structure, the wettability of the surface of a coating formed on various general-purpose resin substrates can be modified in response to thermal stimuli.

[0004] Stimuli-responsive polymers are also sometimes used in cosmetics. For example, Patent Document 2 discloses cosmetics in which an alkylene oxide derivative having a specific structure is combined with an ultraviolet protection agent and an oil phase thickener, thereby improving the ultraviolet protection effect by moisture and heat.

[0005] Patent Document 3 discloses a cosmetic that contains a stimulus-responsive polymer that has a carboxyl group and thus responds to pH stimuli, and that is water-resistant to weakly acidic sweat and the like in the range of 0°C to 40°C, and can be easily washed off with weakly alkaline soapy water and the like.

[0006] JP 2005-154603 A International Publication No. 2020 / 032244 JP 2017-149649 A

[0007] Conventionally, various cosmetics such as sunscreen cosmetics have been formulated with ultraviolet absorbers and ultraviolet scattering agents as ultraviolet protection agents, and these ingredients have the effect of protecting the skin from harmful ultraviolet rays. However, when the film formed on the skin by the sunscreen cosmetics comes into contact with moisture such as water or sweat, the ultraviolet absorbers and ultraviolet scattering agents are leached from the film, inevitably reducing the ultraviolet protection effect. Therefore, various attempts have been made to prevent the leaching of the ultraviolet absorbers and ultraviolet scattering agents, such as improving the water resistance of sunscreen cosmetics.

[0008] By incorporating a film-forming agent that can impart water resistance, it is possible to prevent the UV protection agent from leaking out due to sweat or external moisture. For example, in the cosmetic preparation described in Patent Document 2, whose UV protection effect is improved by moisture and heat, the film formed by this agent is resistant to coming off with sweat or water and is also highly water-resistant.

[0009] However, the film formed by a highly water-resistant cosmetic cannot be easily removed with ordinary detergents or soaps, and a dedicated cleansing agent must be used. In contrast, the cosmetic described in Patent Document 3 is said to be able to be washed off with weakly alkaline soapy water. However, considering the burden on the skin during washing, it is desirable for the cosmetic to be highly water-resistant yet also easy to wash off with water.

[0010] The object of the present invention is to provide a sunscreen cosmetic which has excellent water resistance and can be easily washed off with water.

[0011] That is, the present invention is as follows: [1] A sunscreen cosmetic comprising the following components (A), (B), and (C): (A) 0.1 to 10% by mass of a polyalkylene glycol derivative represented by the following formula (I), (B) 2 to 40% by mass of an ultraviolet protection agent, and (C) 0.01 to 10% by mass of a water-soluble thickener, Z-{O-(EO)} ａ - (BO) ｋ -H} ｍ(I) (In the formula, Z represents a residue obtained by removing hydroxyl groups from a polyhydric alcohol having 3 or more carbon atoms and 3 to 6 hydroxyl groups, m represents an integer of 3 to 6, EO represents an oxyethylene group, BO represents an oxybutylene group, and EO and BO are bonded in a block form. a represents the average number of moles of EO added, k represents the average number of moles of BO added, a is an integer of 1 to 50, and k is an integer of 1 to 50. In addition, (EO) ａ and (BO) ｋ (EO) ａ The mass proportion of is 10 to 75 parts by mass.)

[0012] According to the present invention, a sunscreen cosmetic composition can be obtained which has excellent water resistance and can also be easily washed off with water.

[0013] [Sunscreen Cosmetic] The present invention provides a sunscreen cosmetic.

[0014] The cosmetic of the present invention contains (A) a polyalkylene glycol derivative, (B) an ultraviolet protection agent, and (C) a water-soluble thickener.

[0015] [(A) Polyalkylene Glycol Derivative] In the sunscreen cosmetic of the present invention, component (A) is a polyalkylene glycol derivative represented by the following formula (I): Z-{O-(EO) ａ - (BO) ｋ -H} ｍ (I)

[0016] The polyalkylene glycol derivative represented by formula (I) acts as a temperature-responsive surface modifier. According to the new findings of the present inventors, by appropriately combining this polyalkylene glycol derivative with other components, it is possible to obtain a cosmetic that is highly water-resistant, has improved UV protection effect upon contact with moisture such as water or sweat compared to immediately after application, and can form a film that is easy to wash off with water. Note that the surface modifier refers to a component that can impart functionality to the film obtained by application when added in small amounts to a liquid.

[0017] Furthermore, in the present invention, "temperature responsiveness" refers to a phenomenon that is different from the cloud point phenomenon described above, in which the hydrophilicity / hydrophobicity of a film formed by applying a cosmetic or the like changes to either hydrophilic or hydrophobic at a certain temperature.

[0018] In the formula, Z represents a residue obtained by removing a hydroxyl group from a polyhydric alcohol having 3 to 6 hydroxyl groups and 3 or more carbon atoms. Examples of polyhydric alcohols include glycerin and trimethylolpropane, which have three hydroxyl groups; diglycerin, erythritol, pentaerythritol, sorbitan, and methyl glucoside, which have four hydroxyl groups; xylitol and triglycerin, which have five hydroxyl groups; and sorbitol, inositol, and dipentaerythritol, which have six hydroxyl groups. Preferably, Z is a residue obtained by removing a hydroxyl group from an alcohol having 4 to 6 or more hydroxyl groups. From the viewpoints of facilitating the formation of a coating with high surface uniformity even on uneven substrates, and of enhancing temperature responsiveness so that when incorporated into a sunscreen cosmetic (hereinafter also simply referred to as "cosmetic"), Z is more preferably a residue obtained by removing hydroxyl groups from an alcohol having four hydroxyl groups, particularly preferably a residue obtained by removing hydroxyl groups from diglycerin or pentaerythritol, and most preferably a residue obtained by removing hydroxyl groups from pentaerythritol.

[0019] m is 3 to 6, preferably 4 to 6, and more preferably 4. When m is 3 or more, temperature responsiveness is enhanced, and transition between hydrophobicity and hydrophilicity in response to temperature changes can be easily caused. When m is 6 or less, a highly uniform surface can be easily formed even on an uneven substrate. Furthermore, when m is 3 or more and 6 or less, it is easy to achieve both high water resistance and high ease of washing when incorporated into a cosmetic.

[0020] Furthermore, EO represents an oxyethylene group, and BO represents an oxybutylene group, but from the viewpoint of facilitating polymerization, BO is preferably a 1,2-oxybutylene group. Furthermore, to facilitate polymerization, EO and BO are bonded in a block form. Furthermore, a represents the average number of moles of EO added, and k represents the average number of moles of BO added, a being an integer of 10 to 50, preferably 10 to 40, and particularly preferably 20 to 30, and k being an integer of 3 to 40, preferably 5 to 30, further preferably 10 to 25, and particularly preferably 10 to 15. Furthermore, (EO) ａ and (BO) ｋ (EO) relative to 100 parts by mass of the total amount ａ The mass proportion of EO is 10 to 75 parts by mass, preferably 15 to 60 parts by mass, more preferably 20 to 60 parts by mass, and particularly preferably 30 to 60 parts by mass. The combined use of EO and BO improves temperature responsiveness and makes it easier to form a coating with high surface uniformity even on uneven substrates. Furthermore, the combined use of EO and BO improves the water resistance of the coating.

[0021] In the polyoxyalkylene glycol derivative of the present invention represented by formula (I), an EO block and a BO block are arranged in this order relative to the residue (Z) obtained by removing a hydroxyl group from a polyhydric alcohol. By arranging the blocks in this order, a coating having a highly uniform surface can be formed.

[0022] The polyoxyalkylene glycol derivative of the present invention represented by formula (I) can be produced by a known method, for example, by addition polymerization of oxyethylene and oxybutylene in this order to a polyhydric alcohol having 3 to 6 hydroxyl groups in the presence of an alkali or acid catalyst.

[0023] In the cosmetic of the present invention, the polyalkylene glycol derivative contained as component (A) imparts water resistance and ease of cleaning to the film formed from the cosmetic. Furthermore, upon contact with moisture such as water or sweat, the polyalkylene glycol derivative forms a film with a more uniform surface than before contact, thereby enhancing the UV protection effect of the film formed from the cosmetic.

[0024] The content of the polyalkylene glycol derivative (A) relative to the total mass of the cosmetic of the present invention is preferably 0.1 to 10 mass%, more preferably 0.5 to 8 mass%, and even more preferably 1 to 5 mass%. When the content of the polyalkylene glycol derivative is 0.1 mass% or more, the water resistance of the film is increased and the UV protection power when moisture is added is improved. When the content of the polyalkylene glycol derivative is 10 mass% or less, the film is easily washed.

[0025] [(B) UV Protective Agent] In the cosmetic of the present invention, the UV protective agent contained as component (B) may be an UV absorber or an UV scattering agent. The (B) UV protective agent imparts UV absorption or scattering properties to the cosmetic, thereby imparting UV protection to the base material.

[0026] The ultraviolet absorber may be a liquid ultraviolet absorber or a solid ultraviolet absorber.

[0027] In this specification, "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 without a 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 without a melting point, a state under temperature conditions below the melting point).

[0028] Examples of liquid ultraviolet absorbers include cinnamic acid-based ultraviolet absorbers such as 2-ethylhexyl paramethoxycinnamate, 2-ethoxyethyl paramethoxycinnamate, a mixture of isopropyl paramethoxycinnamate and diisopropyl cinnamate, and methyl bis(trimethylsiloxy)silylisopentyl trimethoxycinnamate; para-aminobenzoic acid-based ultraviolet absorbers such as amyl paradimethylaminobenzoate and 2-ethylhexyl paradimethylaminobenzoate; salicylic acid-based ultraviolet absorbers such as ethylene glycol salicylate, 2-ethylhexyl salicylate, benzyl salicylate, and homomenthyl salicylate; octocrylene; and dimethicodiethyl benzalmalonate. From the viewpoint of making it easier to improve the UV protection effect of the film compared to immediately after application upon contact with moisture such as water or sweat, 2-ethylhexyl paramethoxycinnamate, octocrylene, and dimethicodiethyl benzalmalonate are preferred, with 2-ethylhexyl paramethoxycinnamate and octocrylene being particularly preferred.

[0029] Examples of solid ultraviolet absorbers include diethylaminohydroxybenzoylhexyl benzoate, bisethylhexyloxyphenol methoxyphenyl triazine, methylenebisbenzotriazolyltetramethylbutylphenol, ethylhexyl triazone, 2-ethylhexyl dimethoxybenzylidene dioxoimidazolidinepropionate, and t-butylmethoxydibenzoylmethane. From the viewpoint of making it easier to improve the ultraviolet protection effect of the film compared to immediately after application upon contact with moisture such as water or sweat, diethylaminohydroxybenzoyl hexyl benzoate, bisethylhexyloxyphenol methoxyphenyl triazine, ethylhexyl triazone, and t-butylmethoxydibenzoylmethane are particularly preferred.

[0030] From the viewpoint of making it easier to improve the UV protection effect of the film compared to immediately after application upon contact with moisture such as water or sweat, the cosmetic preferably contains at least a liquid UV absorber, and more preferably contains both a liquid UV absorber and a solid UV absorber.

[0031] The ultraviolet scattering agent is not particularly limited, and specific examples of the ultraviolet scattering agent include fine particle metal oxides such as zinc oxide, titanium oxide, iron oxide, cerium oxide, and tungsten oxide.

[0032] The ultraviolet scattering agent may be untreated or may be subjected to various hydrophobic surface treatments, but is preferably subjected to hydrophobic surface treatments. Surface treatment agents that can be used include those commonly used in the cosmetic field, such as dimethicone, silicones such as alkyl-modified silicones, alkoxysilanes such as octyltriethoxysilane, dextrin fatty acid esters such as dextrin palmitate, and fatty acids such as stearic acid.

[0033] From the viewpoint of ultraviolet protection effect, hydrophobic treated zinc oxide and hydrophobic treated titanium oxide are preferred.

[0034] The cosmetic may contain only an ultraviolet absorber, only an ultraviolet scattering agent, or both an ultraviolet absorber and an ultraviolet scattering agent as the ultraviolet protection agent (B). From the viewpoint of making it easier to improve the ultraviolet protection effect of the film by contact with moisture such as water or sweat compared to immediately after application, the cosmetic preferably contains at least an ultraviolet absorber, and more preferably contains both an ultraviolet absorber and an ultraviolet scattering agent.

[0035] The content of the ultraviolet protection agent (B) relative to the total mass of the cosmetic of the present invention is preferably 2 to 40 mass%, more preferably 3 to 38 mass%, and even more preferably 5 to 30 mass%. When the content of the ultraviolet protection agent is 2 mass% or more, the ultraviolet protection power of the film is enhanced. Furthermore, when the content of the ultraviolet protection agent is 40 mass% or less, the film is easy to wash.

[0036] [(C) Water-soluble Thickener] In the cosmetic of the present invention, the water-soluble thickener contained as component (C) is a water-soluble thickener that can be generally used in cosmetics.

[0037] Examples of water-soluble thickeners include polysaccharide polymers, vinyl polymers, polyoxyethylene polyoxypropylene polymers, acrylic polymers, inorganic polymers, acrylamide polymers, and hydrophobically modified polyether urethanes.

[0038] Examples of polysaccharide polymers include cellulose-based thickeners such as crystalline cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and carboxymethyl cellulose; and natural polymer polysaccharide thickeners such as gellan gum, carrageenan, guar gum, locust bean gum, gum arabic, xanthan gum, dextran, and succinoglucan.

[0039] Examples of vinyl polymers include polyvinyl methyl ether and carboxyvinyl polymer.

[0040] Examples of polyoxyethylene polyoxypropylene polymers include polyoxyethylene polyoxypropylene glycol (150 EO) (30 PO) and polyoxyethylene polyoxypropylene glycol (240 EO) (60 PO).

[0041] Examples of acrylic polymers include acrylic acid / alkyl methacrylate copolymers (acrylates / alkyl acrylate (C10-30)) crosspolymers, alkyl acrylate / alkyl methacrylate polyoxyethylene ester copolymers, alkyl acrylate / alkyl itaconate polyoxyethylene ester copolymers, and steareth-10 allyl ether / alkyl acrylate copolymers.

[0042] Inorganic polymers include bentonite, magnesium aluminum silicate, laponite, hectorite, and silicic anhydride.

[0043] Examples of acrylamide polymers include copolymers of hydroxyethyl acrylate and acryloyldimethyl taurate, copolymers of acrylate and acryloyldimethyl taurate, copolymers of acrylamide and acrylate, copolymers of acrylic acid, acrylamide, acrylate and acryloyldimethyl taurate, and copolymers of vinylpyrrolidone and acryloyldimethyl taurate. More specific examples include (hydroxyethyl acrylate / sodium acryloyldimethyltaurate) copolymer, (sodium acrylate / sodium acryloyldimethyltaurate) copolymer, (acrylamide / ammonium acrylate) copolymer, (acrylic acid / acryloyldimethyltaurate / dimethylacrylamide) crosspolymer, (ammonium acryloyldimethyltaurate / vinylpyrrolidone) copolymer, acrylic acid / acrylamide / sodium acrylate / sodium acryloyldimethyltaurate copolymer, (ammonium acryloyldimethyltaurate / beheneth-25 methacrylate) crosspolymer, and (ammonium acryloyldimethyltaurate / steareth-25 methacrylate) crosspolymer.

[0044] The hydrophobically modified polyether urethane is a polymer having urethane bonds modified with hydrophobic groups, and specific examples thereof include (PEG-240 / decyltetradeceth-20 / HDI) copolymer.

[0045] Among these, from the viewpoint of making it easier to improve the UV protection effect of the film upon contact with moisture such as water or sweat compared to immediately after application, polysaccharide-based polymers, vinyl-based polymers, acrylic-based polymers, and acrylamide-based polymers are preferred, with polysaccharide-based polymers and acrylamide-based polymers being more preferred.

[0046] The content of the water-soluble thickener (C) relative to the total mass of the cosmetic of the present invention is preferably 0.01 to 10 mass%, more preferably 0.02 to 7.5 mass%, and even more preferably 0.05 to 5 mass%. When the content of the water-soluble thickener is 0.01 mass% or more, the UV protection effect of the film is likely to be improved compared to immediately after application upon contact with moisture such as water or sweat. When the content of the water-soluble thickener is 10 mass% or less, it is likely to achieve both water resistance and ease of cleaning of the film.

[0047] The cosmetic preparation of the present invention may contain other components in addition to components (A), (B), and (C), such as moisturizers, thickeners other than component (C), emulsifiers, oils, pH adjusters, surfactants, antioxidants, chelating agents, preservatives, whitening ingredients, pigments, colorants, fragrances, etc.

[0048] The cosmetic of the present invention can be formulated in any desired form. Examples of formulations include lotions, dispersions, emulsions, creams, gels, sticks, cakes, powders, sprays, and aerosols. These preparations can be produced by conventional methods using the components (A), (B), and (C) and the other commonly used components. The cosmetic of the present invention may also be used as a makeup base with sunscreen effect.

[0049] The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. Note that the numerical values ​​shown in the tables of the examples are all in mass % relative to the total cosmetic composition.

[0050] [Synthesis of Compounds 1 to 9] 45 g of pentaerythritol, 50 g of toluene, and 8.0 g of potassium hydroxide were charged into an autoclave. The air in the autoclave was replaced with dry nitrogen. Then, 1,292 g of ethylene oxide was added dropwise from a dropping device at 110°C while stirring, and the mixture was stirred for 2 hours. Subsequently, 1,160 g of 1,2-butylene oxide was added dropwise at 110°C, and the mixture was stirred for 2 hours. The reaction mixture was then removed from the autoclave, neutralized with hydrochloric acid to a pH of 6 to 7, and subjected to reduced pressure treatment at 115°C for 1 hour to remove the toluene and water. Finally, the mixture was filtered to remove salts, synthesizing 2,345 g of Compound 1. Compounds 2 to 7 were synthesized by varying the type of polyhydric alcohol used as raw materials and the amounts of ethylene oxide and 1,2-butylene oxide.

[0051] Compounds 8 and 9 were synthesized using propylene oxide under the same conditions as those for compounds 1 to 7. Compound 8 was synthesized as a random copolymer by simultaneously adding dropwise ethylene oxide and propylene oxide. Compound 9 was synthesized as a random copolymer by simultaneously adding dropwise ethylene oxide, 1,2-butylene oxide, and propylene oxide.

[0052] [Compound 10] 4-Phenylazobenzoic acid PEG-12 methyl ether was used as Compound 10.

[0053] The type of polyhydric alcohol that gave the residue Z in formula (I) and the values ​​of m, a, and k for Compounds 1 to 9 are shown in Table 1. For Compounds 8 and 9, the average number of moles (l) of oxypropylene groups (PO) added is also shown. The values ​​of a, k, and l for Compounds 1 to 9 were calculated from the hydroxyl value.

[0054]

[0055] Compounds 1 to 10 were evaluated as follows.

[0056] [Preparation of Sunscreen Cosmetics] Compounds 1 to 10 were mixed with components (A), (B), and (C) in Tables 1 to 5, and oils other than components (A) and (B), emulsifiers, and lipophilic additives. The mixture was added to an oil phase prepared by heating to 75°C to 80°C, and then an aqueous phase prepared by heating to 75°C to 80°C was added and mixed uniformly using a homomixer to prepare Cosmetics 1 to 19. Dodecane (PARAFOL 12, manufactured by Sasol) was used as the oil.

[0057] In addition, as the oils, emulsifiers, lipophilic additives, and hydrophilic additives other than component (B), component (C), component (A), and component (B) in the table, commercially available products provided for use in cosmetics were used.

[0058] Cosmetics 1 to 19 were evaluated as follows.

[0059] [Evaluation of Water Resistance of Sunscreen Cosmetics] Cosmetics 1 to 19 were applied to a PMMA plate (HELIOPLATE HD6 manufactured by Labsphere) at a concentration of 2 mg / cm. ２ After application, the sample was allowed to stand in a dark place for 20 minutes, and then SPF measurement was performed using an SPF analyzer (UV-2000S manufactured by Labsphere). Measurements were taken at nine points on the plate, and the [SPF before bathing] was calculated from the average value.

[0060] Next, the plate that had been measured was immersed in water at 30°C and stirred in the water for 80 minutes (100 rpm with a 3-1 motor). After that, it was dried for about 60 to 120 minutes until all water droplets on the surface disappeared, and the SPF was measured again to obtain the [SPF after water bath]. The rate of change in SPF after water bath (30°C) was calculated using the following formula (II): Rate of change in SPF after water bath (30°C) = [SPF after water bath] / [SPF before water bath] x 100 (II)

[0061] The water resistance was evaluated based on the rate of change in SPF after the water bath (30°C) according to the following criteria: [Evaluation criteria] ⊚: 130% or more ◯: 115% or more but less than 130% △: 100% or more but less than 115% ×: Less than 100%

[0062] [Evaluation of Cleansing Properties of Sunscreen Cosmetics] Cosmetics 1 to 19 were mixed with 0.05% by mass of Brilliant Blue (a water-soluble blue pigment), and the mixture was applied to a PMMA plate (HELIOPLATE HD6, manufactured by Labsphere) at a concentration of 2 mg / cm ２ After application, the sample was left to stand in a dark place for 20 minutes, then immersed in water at 20°C and stirred in the water for 80 minutes (100 rpm with a 3-1 motor). After that, it was dried for approximately 60 to 120 minutes until all water droplets on the surface disappeared, and the difference in brightness of the applied sample area before and after the water bath was measured using a spectrophotometer (CM-2500c, manufactured by Konica Minolta, Inc.).

[0063] The cleaning rate was calculated according to the following formula, and the water resistance was evaluated according to the following criteria: Cleaning rate = (1 - ΔEa / ΔEb) x 100 ΔEa = brightness of the PMMA plate surface after water bathing ΔEb = brightness of the PMMA plate surface before water bathing [Evaluation criteria] ◎: Cleaning rate of 95% or more ○: Cleaning rate of 85% or more but less than 95% △: Cleaning rate of 75% or more but less than 85% ×: Cleaning rate of less than 75%

[0064] The compositions of Cosmetics 1 to 19, as well as the evaluation results of water resistance and cleansing ability, are shown in Tables 2 to 5.

[0065]

[0066]

[0067]

[0068]

[0069] As shown in Tables 2 to 5, the cosmetics containing components (A) to (C) easily improved their UV protection effect upon contact with water, had high water resistance, and also had good cleansing properties.

[0070] As shown in Table 5, the UV protection effect of the cosmetic composition not containing component (A) was reduced by contact with water.

[0071] Specifically, in Cosmetic 16 (Comparative Example 1), the value of m in component (A) was 2, below the lower limit, and therefore the sunscreen cosmetic exhibited insufficient water resistance. In Cosmetic 17 (Comparative Example 2), the value of m in component (A) was 2, below the lower limit, and therefore the sunscreen cosmetic exhibited insufficient water resistance. In Cosmetic 18 (Comparative Example 3), the value of m in component (A) was 2, below the lower limit, and also the sunscreen cosmetic exhibited no structure derived from BO, and furthermore the oxyalkylene group had a random structure. Therefore, the sunscreen cosmetic exhibited insufficient water resistance. In Cosmetic 19 (Comparative Example 4), the oxyalkylene group structure in component (A) was outside the range of the present invention and also had a random structure. Therefore, the sunscreen cosmetic exhibited insufficient water resistance.

[0072] (Specific Formulation Examples) Below, as specific formulation examples of compositions containing the temperature-responsive surface modifier of the present invention, formulation examples for a sunscreen cosmetic, a makeup base, a two-layer sunscreen mist, and a two-layer sunscreen spray are shown in Tables 6 to 11. It goes without saying that embodiments of the present invention are not limited to these formulation examples. In the tables, "PEG" represents polyethylene glycol, "PPG" represents polypropylene glycol, "BG" represents butylene glycol, and "DPG" represents dipropylene glycol.

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079] This application claims priority based on Japanese Application No. 2023-187696 filed on November 1, 2023, and the contents of the specification and claims of that application are incorporated herein by reference.

[0080] The present invention provides a sunscreen cosmetic that is excellent in water resistance and can be easily washed off with water.

Claims

1. A sunscreen cosmetic comprising the following components (A), (B), and (C): (A) 0.1 to 10% by mass of a polyalkylene glycol derivative represented by the following formula (I); (B) 2 to 40% by mass of an ultraviolet protection agent; and (C) 0.01 to 10% by mass of a water-soluble thickener Z-{O-(EO) ａ - (BO) ｋ -H} ｍ (I) (wherein Z represents a residue obtained by removing hydroxyl groups from a polyhydric alcohol having 3 to 6 hydroxyl groups and 3 or more carbon atoms, m represents an integer of 3 to 6, EO represents an oxyethylene group, BO represents an oxybutylene group, and EO and BO are bonded in the form of blocks. a represents the average number of moles of EO added, k represents the average number of moles of BO added, a is an integer of 1 to 50, and k is an integer of 1 to 50. In addition, (EO) ａ And (BO) ｋ (EO) ａ The mass ratio of is 10 to 75 parts by mass.)

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