Oil-in-water emulsion composition

Abstract

The present invention addresses the problem of providing an oil-in-water type emulsion composition which has excellent durability and ultraviolet protection effect, while having a feeling of use with water during application, emulsion stability, and no precipitation of a solid ultraviolet absorber. The oil-in-water emulsion composition for solving the problem is characterized by containing the following components (A) to (E): (A) an ester copolymer of (meth) acrylic acid-(meth) acrylic acid alkyl ester and (meth) acrylic acid (polyoxyethylene monoalkyl ether); (B) a (hydroxyethyl acrylate / acryloyl sodium dimethyl taurate) copolymer; (C) 15-35 mass% of an ester oil that is liquid at 25 DEG C; (D) 9-20% by mass of a hydrophobized metal oxide; and (E) an ultraviolet absorber that is solid at 25 DEG C. The total content (A) + (B) of the component (A) and the component (B) is 0.2-0.9 mass%, and the content ratio (B) / (A) of the component (B) to the component (A) is 1-50.

Description

Technical Field

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

[0002] In recent years, the development of compositions with various functions has progressed. For example, oil-in-water emulsions have been proposed, offering high UV protection against UVA (long-wavelength ultraviolet rays with a wavelength of 320-400 nm) and UVB (medium-wavelength ultraviolet rays with a wavelength of 290-320 nm). Furthermore, oil-in-water emulsions that offer UV protection, are designed for a variety of usage scenarios, and offer excellent durability, preventing the makeup film from fading due to water or sweat. These compositions are now widely used in foundations and sunscreens.

[0003] These oil-in-water emulsions with UV protection use UV absorbers or metal oxides. Ethylhexyl methoxycinnamate (2-ethylhexyl p-methoxycinnamate) is widely used because it is a solid UV absorber with excellent solubility and absorbs light in the UVB region. However, in recent years, consumer preferences have led to a desire for compositions that do not contain ethylhexyl methoxycinnamate. Research has been conducted on compositions that can achieve UV protection even with low ethylhexyl methoxycinnamate content. For example, an oil-in-water emulsion cosmetic has been proposed that contains a water-insoluble organic UV absorber that is solid at 25°C, a liquid oil, an acrylamide polymer, and hydrophobized metal oxide microparticles, with the combined content of 2-ethylhexyl p-methoxycinnamate and octocrylene being 2% by mass or less of the total amount of the oil-in-water emulsion cosmetic (e.g., Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-155417. Summary of the Invention

[0007] Problems to be solved by the invention

[0008] However, the technology described in Patent Document 1 is excellent in UV protection effect, but is still insufficient in terms of moist feel during application, no precipitation of the solid UV absorber, and durability.

[0009] Oil-in-water emulsions with UV protection are often used in sunscreens, foundations, and other sunscreen cosmetics. These cosmetics are used not only on the body but also on the face, leading many consumers to demand effortless makeup application. Given this backdrop, they are ideal for providing a smooth, comfortable feel that encourages repeated use, and a moisturizing feel upon application is highly desired. Oil-in-water emulsions with high UV protection properties, due to the inclusion of UV absorbers or metal oxides, can significantly burden the skin, leading to a particularly desirable moisturizing feel.

[0010] Therefore, an object of the present invention is to provide an oil-in-water emulsion composition having excellent moist feel during application, emulsion stability, no precipitation of a solid ultraviolet absorber, durability, and ultraviolet protection effect.

[0011] In order to achieve sufficient UV protection without ethylhexyl methoxycinnamate (2-ethylhexyl p-methoxycinnamate), it is necessary to contain a certain amount or more of a UV absorber or metal oxide that is solid at 25°C. Therefore, while developing an oil-in-water emulsion composition that is substantially free of ethylhexyl methoxycinnamate and yet exhibits sufficient UV protection, the present inventors encountered the following problem: when a certain amount or more of a solid UV absorber or metal oxide is contained, the moist feel during application is reduced or the solid UV absorber precipitates, making it impossible to ensure a satisfactory feel and function as a formulation. Furthermore, to improve stability, a water-soluble polymer with high salt tolerance is sometimes incorporated. However, in the present invention, it is extremely difficult to achieve a satisfactory moist feel during application using a general-purpose salt-tolerant water-soluble polymer such as a (sodium acrylate / sodium acryloyldimethyltaurate) copolymer, and the emulsion stability and durability are also insufficient. Furthermore, the following problem was directly faced: if an oil-in-water emulsion composition was to be used to enhance the UV protection effect, a large amount of UV absorbers or metal oxides had to be incorporated. However, these UV absorbers or metal oxides would bind the emulsifying factors and cause the composition to transition to an oil-in-water phase during the emulsification process, making it impossible to obtain an oil-in-water emulsion composition.

[0012] Means for solving problems

[0013] In view of the above-mentioned actual situation, the present inventors have conducted intensive studies and, as a result, have discovered that an oil-in-water emulsion composition containing a UV absorber that is solid at 25°C, a specific amount of a hydrophobized metal oxide, and a specific amount of an ester oil that is liquid at 25°C, wherein the total content and ratio of a (meth)acrylic acid / alkyl (meth)acrylate and a (meth)acrylic acid (polyoxyethylene monoalkyl ether) ester copolymer to a (hydroxyethyl acrylate / sodium acryloyldimethyltaurate) copolymer are within specific ranges, does not undergo phase inversion during production, exhibits excellent emulsion stability, exhibits no precipitation of the solid UV absorber even over time, and also exhibits excellent moist feel during application, durability, and UV protection effect. This has led to the completion of the present invention.

[0014] That is, the present invention provides the following.

[0015] [1] An oil-in-water emulsion composition comprising the following components (A) to (E):

[0016] (A) (meth)acrylic acid, alkyl (meth)acrylate and (meth)acrylic acid (polyoxyethylene monoalkyl ether) ester copolymer;

[0017] (B) (Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate) Copolymer;

[0018] (C) 15-35% by mass of an ester oil that is liquid at 25°C;

[0019] (D) 9 to 20% by mass of a hydrophobized metal oxide;

[0020] (E) a UV absorber that is solid at 25°C,

[0021] The total content of the component (A) and the component (B) (A) + (B) is 0.2 to 0.9% by mass.

[0022] The content mass ratio (B) / (A) of the component (B) relative to the component (A) is 1 to 50.

[0023] [2] The oil-in-water emulsion composition according to [1], wherein the oil-in-water emulsion composition does not substantially contain ethylhexyl methoxycinnamate.

[0024] [3] The oil-in-water emulsion composition according to [1] or [2], wherein the component (A) is an (acrylates / behenyl ether methacrylate) copolymer.

[0025] [4] The oil-in-water emulsion composition described in [1] or [2], wherein the component (E) is one or more selected from the group consisting of diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 4-tert-butyl-4'-methoxydibenzoylmethane, drometrizole trisiloxane, 2-ethylhexyl dimethoxybenzylidenedioxoimidazolidinepropionate and 2-hydroxy-4-methoxybenzophenone.

[0026] [5] The oil-in-water emulsion composition according to [1] or [2], further comprising ethanol as a component (F).

[0027] [6] The oil-in-water emulsion composition according to [1] or [2], wherein the oil-in-water emulsion composition does not substantially contain a surfactant.

[0028] [7] The oil-in-water emulsion composition according to [1] or [2], which has a viscosity at 30°C of 5,000 to 10,000 mPa·s.

[0029] [8] The oil-in-water emulsion composition according to [1] or [2], wherein the oil-in-water emulsion composition is a cosmetic for sunscreen use.

[0030] Effects of the Invention

[0031] The oil-in-water emulsion composition of the present invention is excellent in emulsion stability and in the absence of precipitation of a UV absorber that is solid at 25° C. It also has a moist feel during application, durability, and an excellent UV protection effect.

[0032] Furthermore, the present invention provides an oil-in-water emulsion composition that exhibits a sufficient UV protection effect even when substantially free of ethylhexyl methoxycinnamate (2-ethylhexyl p-methoxycinnamate), and is excellent in emulsion stability, moist feel during application, absence of precipitation of a solid UV absorber, and durability.

[0033] Furthermore, the present invention can provide an oil-in-water emulsion composition that exhibits sufficient emulsion stability even when substantially containing no surfactant, and that has a moist feel during application, exhibits no precipitation of the solid UV absorber, and exhibits excellent durability and UV protection effect. DETAILED DESCRIPTION

[0034] Hereinafter, a suitable embodiment for implementing the present invention will be described. It should be noted that the embodiment described below represents an example of a representative embodiment of the present invention, and the scope of the present invention is not to be narrowly interpreted thereby. In addition, in this specification, unless otherwise specified, the percentage is expressed based on mass. In addition, the upper limit value (below) and the lower limit value (above) of each numerical range (~) can be arbitrarily combined as needed. In this specification, "X~Y" indicating a range includes X and Y, and means "above X and below Y".

[0035] <Component (A): (Meth)acrylic acid, (meth)acrylic acid alkyl ester, and (meth)acrylic acid (polyoxyethylene monoalkyl ether) ester copolymer>

[0036] The ester copolymer of component (A) used in the present invention is a copolymer composed of an ester of (meth)acrylic acid and polyoxyethylene alkyl ether and one or more monomers selected from (meth)acrylic acid or simple esters thereof.

[0037] The component (A) is obtained by copolymerizing a monomer (a) selected from (meth) acrylic acid and (meth) acrylic acid alkyl esters with a monomer (b) composed of (meth) acrylic acid polyoxyalkylene alkyl ether. There are no particular restrictions on the bonding method, and it can be any of block bonding, random bonding, etc. In addition, it can contain other monomers and can also have a cross-linked structure. When containing other monomers, the other monomers are preferably less than 10 mol% (lower limit 0 mol%) relative to all monomers, more preferably less than 5 mol% (lower limit 0 mol%), and further preferably less than 1 mol% (lower limit 0 mol%). Here, the content of structural unit (a) and structural unit (b) is consistent with the addition amount of monomer (a) and monomer (b) in the manufacturing stage.

[0038] The content ratio of the structural unit (a) to the structural unit (b) is not particularly limited, and for example, the molar ratio is structural unit (a):structural unit (b)=1:100 to 100:1.

[0039] In addition, in this specification, (meth)acrylic acid means an expression including both acrylic acid and methacrylic acid.

[0040] In the alkyl (meth)acrylate, the alkyl group of the alkyl ester preferably has 1 to 22 carbon atoms, more preferably 1 to 18 carbon atoms, and even more preferably 1 to 8 carbon atoms. Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, and propyl (meth)acrylate.

[0041] In the polyoxyethylene monoalkyl (meth)acrylate, the number of moles of polyoxyethylene added is preferably 10 to 30, more preferably 12 to 25, and even more preferably 20 to 25.

[0042] In the polyoxyethylene monoalkyl (meth)acrylate ether, the alkyl group of the alkyl ether preferably has 12 to 24 carbon atoms, more preferably 16 to 22 carbon atoms. Specifically, polyoxyethylene monoalkyl (meth)acrylate ethers are more preferably esters of acrylic acid and polyoxyethylene (20) stearyl ether, esters of methacrylic acid and polyoxyethylene (20) stearyl ether, esters of acrylic acid and polyoxyethylene (25) behenyl ether, and esters of methacrylic acid and polyoxyethylene (25) behenyl ether. More preferably, are esters of methacrylic acid and polyoxyethylene (25) behenyl ether. It should be noted that the numerical values in parentheses represent the number of moles of ethylene oxide added.

[0043] More specifically, examples of the ester copolymer of component (A) include (meth)acrylic acid / alkyl (meth)acrylate / polyoxyethylene (meth)acrylate alkyl ether copolymers such as acrylic acid (esters) / methacrylic acid polyoxyethylene (20) cetyl ether copolymer, acrylic acid (esters) / methacrylic acid polyoxyethylene (20) stearyl ether copolymer, and acrylic acid (esters) / methacrylic acid polyoxyethylene (25) behenyl ether copolymer. The numerical values in parentheses represent the number of moles of ethylene oxide added.

[0044] Among them, as component (A), from the viewpoint of emulsion stability and moist feel during application, (acrylates / stearyl ether methacrylate) copolymer and (acrylates / beheneth methacrylate) copolymer are preferred, (acrylates / beheneth methacrylate) copolymer is more preferred, and (acrylates / beheneth-25 methacrylate) copolymer is even more preferred. Examples of these commercially available products include acrylates / methacrylate polyoxyethylene (20) stearyl ether copolymer ((acrylates / steareth-20 methacrylate) copolymer) with a trade name of ACULYN (registered trademark) 22 (manufactured by Rohm and Haas), acrylates / methacrylate polyoxyethylene (25) behenyl ether copolymer ((acrylates / beheneth-25 methacrylate) copolymer) with a trade name of ACULYN 28 (manufactured by Rohm and Haas), and NOVETHIX (registered trademark) L-10 (manufactured by Lubrizol).

[0045] Component (A) can usually be used by neutralizing with an alkaline substance. In this case, examples of the alkaline substance used include: alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, diisopropanolamine, and triisopropanolamine; inorganic bases such as sodium hydroxide, potassium hydroxide, and magnesium hydroxide; and basic amino acids such as L-arginine. These alkaline substances can be added in an amount sufficient to neutralize component (A). The amount of the alkaline substance added is preferably 20 to 150% by mass relative to component (A).

[0046] The content of component (A) in the present invention is not particularly limited, but the lower limit is preferably 0.01% by mass (hereinafter abbreviated as %) or more, more preferably 0.02% or more, even more preferably 0.04% or more, and even more preferably 0.05% or more. The upper limit is preferably 0.5% or less, more preferably 0.3% or less, even more preferably 0.25% or less, and even more preferably 0.2% or less. This range is more preferred because it provides a more moist feel during application, emulsion stability, durability, and the like.

[0047] The content of component (A) in the present invention is not particularly limited, but is preferably 0.01 to 0.5%, more preferably 0.02 to 0.3%, further preferably 0.04 to 0.25%, and even more preferably 0.05 to 0.2%. This range is more preferred because it provides a more moist feel during application, emulsion stability, and durability.

[0048] <Component (B): (Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate) Copolymer>

[0049] Component (B) used in the present invention is a copolymer composed of hydroxyethyl acrylate and sodium salt of acryloyldimethyltaurate. Commercially available products of (hydroxyethyl acrylate / sodium acryloyldimethyltaurate) copolymers include, for example, SIMULGEL FL (manufactured by SEPPIC).

[0050] The content of component (B) in the present invention is not particularly limited, but the lower limit is preferably 0.2% or more, more preferably 0.24% or more, even more preferably 0.25% or more, and even more preferably 0.3% or more. The upper limit is preferably less than 0.9%, more preferably 0.8% or less, even more preferably 0.7% or less, and even more preferably 0.6% or less. This range is more preferred because it provides a more moist feel during application, emulsion stability, and durability.

[0051] The content of component (B) in the present invention is not particularly limited, but is preferably 0.2% or more and less than 0.9%, more preferably 0.24 to 0.8%, even more preferably 0.25 to 0.7%, and even more preferably 0.3 to 0.6%. This range is more preferred because it provides a more moist feel during application, emulsion stability, and durability.

[0052] In the present invention, the total content (A) + (B) of component (A) and component (B) is, from the viewpoint of emulsion stability, etc., set to a lower limit of 0.2% or more, preferably 0.25% or more, more preferably 0.3% or more, further preferably 0.35% or more, and even more preferably 0.4% or more. Furthermore, from the viewpoint of a moist feel during application and durability, the upper limit is set to 0.9% or less, preferably 0.85% or less, more preferably 0.8% or less, further preferably 0.7% or less, and even more preferably 0.6% or less.

[0053] In the present invention, the total content of component (A) and component (B), (A) + (B), is 0.2 to 0.9%, preferably 0.25 to 0.85%, more preferably 0.3 to 0.8%, further preferably 0.35 to 0.7%, and even more preferably 0.4 to 0.6%. This range is more preferred because it provides a more moist feel during application, emulsion stability, durability, and the like.

[0054] In the present invention, the mass ratio (B) / (A) of component (B) to component (A) is, from the viewpoint of a moist feel during application, emulsion stability, and durability, set to a lower limit of 1 or greater, preferably 2 or greater, more preferably 2.5 or greater, and even more preferably 3 or greater. Furthermore, from the viewpoint of emulsion stability, etc., the upper limit is 50 or less, preferably 40 or less, more preferably 30 or less, even more preferably 20 or less, and even more preferably 10 or less.

[0055] In the present invention, the mass ratio (B) / (A) of component (B) relative to component (A) is 1 to 50, preferably 2 to 40, more preferably 2.5 to 30, further preferably 3 to 20, and further preferably 3 to 10. This range is more preferred because it provides better moist feel during application, emulsion stability, durability, and the like.

[0056] <Component (C): Ester oil that is liquid at 25°C>

[0057] Component (C) used in the present invention is an ester composed of a linear or branched fatty acid and a linear or branched monovalent or polyvalent alcohol. Liquid at 25°C means a viscosity of 7000 mPa·s or less when measured at 25°C and 1 atm using a Brookfield viscometer (spindle 2).

[0058] The component (C) of the present invention is not particularly limited as long as it is an ester oil that is liquid at 25°C. For example, it may be of any origin, such as animal oil, vegetable oil, or synthetic oil. Examples thereof include jojoba oil, alkyl (C12-C15) benzoate, cetyl 2-ethylhexanoate, isononyl isononanoate, isotridecyl isononanoate, isopropyl myristate, isopropyl palmitate, octyldodecyl myristate, isotridecyl isononanoate, ethyl oleate, glyceryl tri-2-ethylhexanoate, propylene glycol dicaprate, neopentyl glycol dicaprate, polyglyceryl-2 triisostearate, tris-behenate. Glyceryl stearate, diisostearyl malate, ethylhexyl dimethyl para-aminobenzoate, ethylhexyl salicylate, diethylhexyl succinate, tri(caprylic / capric)glyceryl, 2-ethylhexyl hydroxystearate, ethylhexyl palmitate, polyglyceryl-2 diisostearate, polyglyceryl-2 tetraisostearate, neopentyl glycol diethylhexanoate, pentaerythrityl tetraethylhexanoate, diisopropyl sebacate, dibutyl adipate, dicaprylyl carbonate, tocopheryl acetate, olive oil, castor oil, mink oil, macadamia ternifolia seed oil, meadowfoam seed oil, rosehip oil, rice bran oil, avocado oil, etc.

[0059] The component (C) of the present invention preferably has a molecular weight of 200 to 1000, more preferably 200 to 800, and even more preferably 200 to 500, from the viewpoint of improving the moist feel during application and the solubility of the solid ultraviolet absorber. Examples thereof include alkyl (C12-C15) benzoates, propylene glycol dicaprate, neopentyl glycol dicaprate, isononyl isononanoate, isotridecyl isononanoate, cetyl 2-ethylhexanoate, glyceryl tri-2-ethylhexanoate, polyglyceryl-2 triisostearate, tri(caprylic / capric)glyceryl, 2-ethylhexyl hydroxystearate, diisostearyl malate, diisopropyl sebacate, dicaprylyl carbonate, dibutyl adipate, and ethylhexyl salicylate. Among these, alkyl (C12-C15) benzoate and propylene glycol dicaprylate are more preferred because they provide a moist feel during application, excellent solubility of the solid UV absorber, and a particularly excellent effect in terms of preventing precipitation of the solid UV absorber. As component (C), commercially available products such as FINSOLV TN (manufactured by Innospec Performance Chemicals Europe Limited) and NIKKOL PDD (manufactured by Nippon Surfactant Industries) can be used. These can be used alone or in combination, as needed.

[0060] In the present invention, component (C) is not particularly limited as long as it is an ester oil that is liquid at 25°C. From the perspective of improving the moist feel during application and the solubility of the solid UV absorber, the IOB value is preferably 0.1 to 0.5, more preferably 0.1 to 0.4, and even more preferably 0.1 to 0.3. The IOB value is an index that represents the polarity of an organic compound as a balance between its inorganic (inorganic) and organic (organic) properties. It is expressed as IOB value = inorganic value / organic value. A compound with a larger value is considered to be more hydrophilic, while a smaller value is considered to be more lipophilic.

[0061] The content of component (C) in the present invention is, from the perspectives of a moist feel during application, no precipitation of the solid UV absorber, durability, and UV protection effect, to a lower limit of 15% or more, preferably 17% or more, and more preferably 19% or more. From the perspectives of a moist feel during application, durability, emulsion stability, etc., the upper limit is 35% or less, preferably 33% or less, and more preferably 30% or less.

[0062] The content of component (C) in the present invention is 15 to 35%, preferably 17 to 33%, and more preferably 19 to 30%. This range is preferred because it provides a moist feel during application, prevents precipitation of the solid UV absorber, and improves emulsion stability, durability, and UV protection.

[0063] <Component (D): Hydrophobized Metal Oxide>

[0064] Component (D) used in the present invention is a component obtained by coating the surface of a metal oxide with a hydrophobizing agent to enhance dispersibility in an oil phase.

[0065] The metal oxide of the present invention is not particularly limited as long as it is a metal oxide that blocks ultraviolet rays by absorbing, scattering, reflecting, or extinct ultraviolet rays in a wide range of UVB to UVA (290 to 400 nm) and is commonly used in cosmetics, quasi-drugs, and pharmaceuticals. From the perspective of easy commercial availability, preferred examples include: one or more selected from zinc oxide, titanium oxide, cerium oxide, iron oxide, and chromium oxide. The metal oxide is not particularly limited, but from the perspective of ultraviolet protection effects, it is preferably one or more selected from zinc oxide, titanium oxide, and cerium oxide. In addition, the metal oxide may contain trace elements with a positive divalent or higher valence, and metals such as iron, zirconium, calcium, manganese, magnesium, and yttrium may be included in the metal oxide alone or in appropriate combinations of two or more.

[0066] The particle size of the metal oxide is not particularly limited. From the viewpoint of ultraviolet protection effect, the average particle size is preferably 1 nm to 1 μm, more preferably 3 nm to 100 nm, and even more preferably 5 nm to 50 nm.

[0067] In addition, in this invention, an average particle diameter can be measured as an average particle diameter based on the image analysis method of a transmission electron microscope image.

[0068] On a glass slide, approximately 10 mg of the sample was stirred and fully dispersed with 1-propanol to obtain a dispersion. The dispersion was spread out to obtain a thin film sample. The sample film was placed on a transmission electron microscope (TEM) measurement grid with a support film attached. The grid (dried coating) was placed on a transmission electron microscope device (S-4800, Hitachi High-Technologies Co., Ltd.) and observed to obtain an image of the dry coating reflected by each particle. The image of the dry coating surface was processed by measuring the number of particles for each 1000 using an image analysis particle size distribution measuring device (Mac-View, Mountech Co., Ltd.), and the particle size was measured. Thus, the average particle size D50 of the sample (powder) can be obtained by image analysis of the transmission electron microscope (TEM) image.

[0069] The shape of the metal oxide is not particularly limited, and examples thereof include granular, spherical, plate-like, spindle-like, dendritic, and balloon-like shapes. From the viewpoint of ultraviolet protection effects, granular, spherical, plate-like, and spindle-like shapes are preferred.

[0070] The metal oxide is not particularly limited. Examples of commercially available zinc oxide include FINEX-25, FINEX-50, and FINEX-75 (manufactured by Sakai Chemical Co., Ltd.); MZ300 series, MZ500 series, and MZ700 series (manufactured by TAYCA); and ZnO-350 (manufactured by Sumitomo Osaka Cement Co., Ltd.). Titanium oxide includes TTO-55 series and TTO-51 series (manufactured by Ishihara Sangyo Co., Ltd.); and JR series and JA series (manufactured by TAYCA). Examples of cerium oxide include high-purity cerium sold by Nikki Co., Ltd. and AGC Seimi Chemical Co., Ltd.

[0071] The hydrophobizing agent as component (D) is not particularly limited as long as it is an ingredient generally used in cosmetics, quasi-drugs, pharmaceuticals, etc., and examples thereof include silicone treatment agents, fluorine treatment agents, organic titanate treatment agents, fatty acid treatment agents, lecithin treatment agents, amino acid treatment agents, acylated amino acid treatment agents, etc. Among these, from the viewpoint of emulsion stability, etc., one or more selected from silicone treatment agents, organic titanate treatment agents, fatty acid treatment agents, and acylated amino acid treatment agents are preferred, and one or more selected from silicone treatment agents, organic titanate treatment agents, and acylated amino acid treatment agents are particularly preferred.

[0072] Examples of the silicone treatment agent include: chain silicones such as low-polymerization dimethylpolysiloxane, high-polymerization dimethylpolysiloxane, and methylphenylpolysiloxane; modified silicones such as amino-modified silicone, alkyl-modified silicone, and alkoxy-modified silicone; silicone resins such as trimethylsiloxysilicate and acrylic-silicone graft copolymers; silicone rubbers; partially or fully cross-linked organopolysiloxanes; silanizing agents; silane coupling agents, and the like, and one or more selected from these can be used.

[0073] The silane coupling agent is not particularly limited, but trialkoxyalkylsilane is preferred. Trialkoxyalkylsilane is a compound having three alkoxy groups and one alkyl group bonded to a silicon atom, and is a compound in which the surface of the powder is chemically modified by reacting the alkoxy group with a hydroxyl group on the surface of the powder. The alkoxy group in the trialkoxyalkylsilane is preferably a methoxy group, ethoxy group, propoxy group, etc., which are alkoxy groups having 1 to 3 carbon atoms. In addition, the alkyl group in the trialkoxyalkylsilane is preferably a hexyl group, octyl group, decyl group, octadecyl group, etc., which are alkyl groups having 6 to 18 carbon atoms. Examples of such trialkoxyalkylsilanes include trimethoxyhexylsilane, trimethoxyoctylsilane, trimethoxydecylsilane, trimethoxyoctadecylsilane, triethoxyhexylsilane, triethoxyoctylsilane (OTS), triethoxydecylsilane, triethoxyoctadecylsilane, etc. Among these, at least one selected from trimethoxyoctylsilane and triethoxyoctylsilane (OTS) is more preferable from the viewpoint of emulsion stability.

[0074] Examples of the organic titanate treatment agent include alkyl titanates of long-chain carboxylic acid type, pyrophosphate type, phosphorous acid type, and amino acid type, and preferably alkyl titanates having an alkyl group with 8 to 24 carbon atoms. Specific examples of the alkyl titanates include long-chain carboxylic acid type alkyl titanates such as isopropyl triisostearoyl titanate (ITT), isopropyl trioctanoyl titanate, isopropyl di(methacryloyl) isostearyl titanate, isopropyl isostearyl diacryloyl titanate, and diisostearoyl ethylene titanate. Examples of the pyrophosphate type alkyl titanates include tetraisopropyl bis(dioctylphosphite) titanate, tetraoctyl bis(di(tridecyl)) Examples of the alkyl titanates include tris(dioctyl pyrophosphate)titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite)titanate, and phosphite-type alkyl titanates include isopropyl tris(dioctyl pyrophosphate)titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, and bis(dioctyl pyrophosphate)ethylene titanate. Examples of the alkyl titanates include amino acid-type alkyl titanates include isopropyl tris(N-amidoethyl / aminoethyl) titanate.

[0075] Examples of the fatty acid treating agent include fatty acids or their metal salts. From the perspective of redispersibility of component (D), the fatty acid preferably has 12 to 18 carbon atoms. Examples of their salts include calcium, magnesium, zinc, and aluminum, with aluminum salts being preferred. Among these, stearic acid or its metal salts are particularly preferred.

[0076] Examples of the amino acid treatment agent include proline, hydroxyproline, alanine, glycine, sarcosine, lysine, aspartic acid, and glutamic acid, including salts thereof.

[0077] The acylated amino acid treating agent is not particularly limited. The fatty acid constituting the acyl group is preferably a fatty acid having 6 to 23 carbon atoms, more preferably a fatty acid having 8 to 20 carbon atoms, and particularly preferably stearoyl glutamic acid, lauroyl aspartic acid, dilauroyl glutamic acid lysine, and lauroyl lysine.

[0078] As the hydrophobic treatment of component (D), from the viewpoints of emulsion stability, moist feel during application, durability, and UV protection effect, it is preferred that one or more selected from the group consisting of methyl polysiloxane (dimethicone) treatment, triethoxycaprylylsilane (OTS) treatment, isopropyl triisostearoyl titanate (ITT) treatment, stearic acid treatment, and lauroyl lysine treatment.

[0079] The method for the hydrophobization treatment of component (D) is not particularly limited and can be manufactured by a generally known method. For example, by adding a hydrophobization treatment agent and powder particles to be treated in a solvent, stirring with a ball mill, etc., drying as needed, repeatedly washing with water, filtering, removing inclusions, drying, crushing, and obtaining a target hydrophobization treatment powder. In addition, a plurality of compounds as surface treatment agents can be surface treated simultaneously, or any one compound can be pre-surface treated and then further surface treated with other compounds. The amount of the hydrophobization treatment agent used for the treatment of metal oxide is not particularly limited, and is preferably 5 to 40% and more preferably 10 to 35% from the viewpoint of emulsion stability or the moist feeling during application, durability, or ultraviolet protection effect.

[0080] Regarding the content of component (D) in the present invention, from the viewpoint of durability and UV protection effect, the lower limit is 9% or more, preferably 10% or more, and more preferably 12% or more. Furthermore, from the viewpoint of a moist feel during application and emulsion stability, the upper limit is 20% or less, preferably 19% or less, and more preferably 18% or less.

[0081] The content of component (D) in the present invention is 9 to 20%, preferably 10 to 19%, and more preferably 12 to 18%. This range is preferred because it provides a moist feel during application, emulsion stability, durability, and UV protection.

[0082] <Component (E): UV absorber that is solid at 25°C>

[0083] Component (E) used in the present invention may be any component that can be contained in cosmetics, quasi-drugs, drugs, etc., and is preferably selected from ultraviolet absorbers that are insoluble in water and readily soluble in oil. Here, being solid at 25°C means having no fluidity at 25°C.

[0084] Examples of the component (E) include 2-ethylhexyl dimethoxybenzylidenedioxoimidazolidine propionate, diethylaminohydroxybenzoylhexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, drometrizole trisiloxane, 4-tert-butyl-4′-methoxydibenzoylmethane, and 2-hydroxy-4-methoxybenzophenone. In the present invention, from the viewpoint of durability and UV protection effect, more preferably, one or more selected from diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, and drometrizole trisiloxane are used. Furthermore, more preferably, two or more selected from diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, and drometrizole trisiloxane are used, and more preferably, three or more selected from the group consisting of diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, and drometrizole trisiloxane are used. There is no particular limitation on the combination of two or more or three or more. Among the combinations of three or more, a combination of diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine and 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, or a combination of diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine and drometrizole trisiloxane is particularly preferred.

[0085] Here, regarding component (E), Uvinul Aplus (manufactured by BASF) can be used as diethylaminohydroxybenzoyl hexyl benzoate; Tinosorb S (manufactured by BASF) can be used as 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine; Uvinul T-150 (manufactured by BASF) can be used as 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine; and commercially available products such as PARSOL 1789 (manufactured by DSM) can be used as 4-tert-butyl-4'-methoxydibenzoylmethane.

[0086] The content of component (E) in the present invention is not particularly limited. However, from the perspective of UV protection effects, the lower limit is preferably 1% or more, more preferably 2% or more, and even more preferably 4% or more. Furthermore, from the perspective of preventing precipitation of the solid UV absorber, ensuring emulsion stability, and providing a moist feel during application, the upper limit is preferably 20% or less, more preferably 10% or less, and even more preferably 8% or less.

[0087] The content of component (E) in the present invention is not particularly limited, but is preferably 1 to 20%, more preferably 2 to 10%, and even more preferably 4 to 8%. This range is preferred because it provides a moist feel during application, prevents precipitation of the solid UV absorber, improves emulsion stability, and enhances UV protection.

[0088] <Ingredient (F): Ethanol>

[0089] In the present invention, further containing the component (F) is more preferred because a moist feel during application, no precipitation of the solid ultraviolet absorber, and durability can be appropriately exhibited.

[0090] The content of component (F) in the present invention is not particularly limited, but the lower limit is preferably 1% or more, more preferably 3% or more, and even more preferably 5% or more. The upper limit is preferably 15% or less, more preferably 12% or less, and even more preferably 9% or less. This range is preferred because it provides a moist feel during application, prevents precipitation of the solid UV absorber, and improves durability.

[0091] The content of component (F) of the present invention is not particularly limited, but is preferably 1 to 15%, more preferably 3 to 12%, and even more preferably 5 to 9%. This range is preferred because it provides a moist feel during application, prevents precipitation of the solid UV absorber, and improves durability.

[0092] Furthermore, the present invention enables an oil-in-water emulsion composition to exhibit excellent UV protection effects even when substantially free of ethylhexyl methoxycinnamate (2-ethylhexyl p-methoxycinnamate). In the present invention, substantially free of ethylhexyl methoxycinnamate is more preferred from the perspective of consumer preference. In the present invention, substantially free of ethylhexyl methoxycinnamate means that the content of the oil-in-water emulsion composition is 1% or less, preferably 0.5% or less, more preferably 0.1% or less, and even more preferably 0% (no ethylhexyl methoxycinnamate).

[0093] Furthermore, in the present invention, from the perspective of more appropriately achieving a moist feel during application and durability, it is preferably substantially free of surfactants. Surfactants commonly used in cosmetics are acceptable, including nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants. In the present invention, it is more preferably substantially free of cationic surfactants and amphoteric surfactants. In the present invention, "substantially free of surfactants" means that the content of the oil-in-water emulsion composition is 0.5% or less, more preferably 0.2% or less, and even more preferably 0.1% or less.

[0094] The oil-in-water emulsion composition of the present invention may generally contain, in addition to the above-mentioned ingredients, ingredients usable in cosmetics, quasi-drugs, drugs, etc., water, surfactants, oils other than component (C), gelling agents, powders other than component (D), alcohols other than component (F), water-soluble polymers other than components (A) and (B), film-forming agents, resins, moisturizers, antibacterial agents, fragrances, deodorants, salts, chelating agents, ultraviolet absorbers other than component (E), pH adjusters, cooling agents, plant extracts, vitamins, and beauty ingredients such as amino acids, etc., within a range that does not impair the effects of the present invention.

[0095] The oil-in-water emulsion composition of the present invention may contain water, without particular limitation, as long as it is water that can be contained in cosmetics, quasi-drugs, pharmaceuticals, and the like. The water may be purified water, hot spring water, deep-seated water, or plant-derived steam distilled water, and one or more of these may be appropriately selected and used as needed. The water content is not particularly limited and may be appropriately adjusted based on the amounts of other ingredients, but can generally comprise 30 to 70% of the oil-in-water emulsion composition.

[0096] The oil-in-water emulsion composition of the present invention can be implemented in various forms, including liquid, gel, emulsion, cream, semi-solid, solid, and mousse. However, to achieve the effects of the present invention, a gel is preferred. Here, the term "gel" means a viscosity of 10,000 mPa·s or less, preferably 9,000 mPa·s or less, and more preferably 8,000 mPa·s or less, as measured at 30°C using a Brookfield rotational viscometer. The lower limit is 5,000 mPa·s or more, preferably 6,000 mPa·s or more.

[0097] The range is preferably 5,000 to 10,000 mPa·s, more preferably 6,000 to 9,000 mPa·s, and even more preferably 6,000 to 8,000 mPa·s at 30°C.

[0098] The oil-in-water emulsion composition of the present invention can be used directly as a final formulation, or it can be mixed with other ingredients to form a final formulation. Examples of final formulations include cosmetics. Specifically, these can be various cosmetics, including skincare cosmetics such as lotions, creams, serums, lip balms, and sunscreens; color cosmetics such as foundations, primers, blushers, eyeshadows, lipsticks, and lip glosses; and cosmetics for the scalp or hair such as conditioners, hair creams, and hair styling agents. In the present invention, cosmetics for sunscreen applications are preferred because they allow for more effective and tangible effects. For sunscreen applications, any product that provides UV protection, such as sunscreens (toners, creams, lotions, serums, etc.), primers, and foundations, can be used. Application methods include application with hands, fingers, or cotton pads; application by impregnation into nonwoven fabrics; and application as a spray or aerosol.

[0099] The content of the oil-in-water emulsion composition of the present invention contained in the cosmetic is not particularly limited, but is preferably 20 to 100%.

[0100] (Manufacturing Method)

[0101] The oil-in-water emulsion composition of the present invention can be produced by a commonly known method. Any dispersing / emulsifying device such as a general disperser may be used as the production equipment. For example, the composition can be produced by mixing components (A) and (B) in a disperser and heating them, adding components (C), (D), and (E) dissolved by heating to the mixture, uniformly mixing them in a disperser, cooling, and then adding component (F) and uniformly mixing them.

[0102] In addition, the present invention can also adopt the following configurations.

[0103] <1> An oil-in-water emulsion composition comprising the following components (A) to (E):

[0104] (A) (meth)acrylic acid, alkyl (meth)acrylate and (meth)acrylic acid (polyoxyethylene monoalkyl ether) ester copolymer;

[0105] (B) (Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate) Copolymer;

[0106] (C) 15-35% by mass of an ester oil that is liquid at 25°C;

[0107] (D) 9 to 20% by mass of a hydrophobized metal oxide;

[0108] (E) a UV absorber that is solid at 25°C,

[0109] The total content of the component (A) and the component (B) (A) + (B) is 0.2 to 0.9% by mass.

[0110] The content mass ratio (B) / (A) of the component (B) relative to the component (A) is 1 to 50.

[0111] <2> The oil-in-water emulsion composition according to <1>, wherein the oil-in-water emulsion composition does not substantially contain ethylhexyl methoxycinnamate.

[0112] <3> The oil-in-water emulsion composition according to <1> or <2>, wherein the component (A) is an (acrylates / behenyl ether methacrylate) copolymer.

[0113] <4> The oil-in-water emulsion composition according to any one of <1> to <3>, wherein the component (E) is one or more selected from the group consisting of diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 4-tert-butyl-4'-methoxydibenzoylmethane, drometrizole trisiloxane, 2-ethylhexyl dimethoxybenzylidenedioxoimidazolidinepropionate, and 2-hydroxy-4-methoxybenzophenone.

[0114] <5> The oil-in-water emulsion composition according to any one of <1> to <4>, further comprising ethanol as a component (F).

[0115] <6> The oil-in-water emulsion composition according to any one of <1> to <5>, wherein the oil-in-water emulsion composition does not substantially contain a surfactant.

[0116] <7> The oil-in-water emulsion composition according to any one of <1> to <6>, which has a viscosity at 30°C of 5,000 to 10,000 mPa·s.

[0117] <8> The oil-in-water emulsion composition according to any one of <1> to <7>, wherein the oil-in-water emulsion composition is a cosmetic for sunscreen use.

[0118] Example

[0119] Hereinafter, the present technology will be described in further detail based on examples, etc. It should be noted that the examples, etc. described below are examples of representative embodiments, etc. of the present technology, and the scope of the present technology should not be interpreted narrowly thereby.

[0120] [Examples 1 to 16 and Comparative Examples 1 to 13: Sunscreen (Oil-in-Water Type)]

[0121] Sunscreens were prepared according to the compositions shown in Tables 1 and 2 and the following production method. The resulting sunscreens were evaluated for (a) moist feel upon application, (b) absence of solid UV absorber precipitation (5°C / 1M), (c) emulsion stability, (d) durability, and (e) UV protection effect according to the following methods. The results are shown in Tables 1 and 2.

[0122] [Table 1]

[0123]

[0124] [Table 2]

[0125]

[0126] ※The evaluation of "-" means that the emulsion stability immediately after production could not be ensured and the evaluation could not be performed, or the evaluation was not performed because the composition was not an oil-in-water emulsion.

[0127] Note 1: NOVETHIX L-10 POLYMER (manufactured by Lubrizol Advanced Materials)

[0128] Note 2: SIMULGEL FL (manufactured by SEPPIC)

[0129] Note 3: SIMULGELEG QD (manufactured by SEPPIC)

[0130] Note 4: MZ-500 (manufactured by TAYCA) was used as zinc oxide. The OTS treatment amount was set to 10% by mass relative to the mass of zinc oxide, and the dimethicone treatment amount was set to 10%.

[0131] Note 5: MZ-500 (average particle size: 25 nm) (manufactured by TAYCA)

[0132] Note 6: Uvinul A PLUS GRANULAR (manufactured by BASF)

[0133] Note 7: TINOSORB S (manufactured by BASF)

[0134] Note 8: UVINUL T150 (manufactured by Nikko Chemical Co., Ltd.)

[0135] Note 9: Dromtriazole trisiloxane (produced by L'Oréal Japan)

[0136] (Manufacturing Method)

[0137] A: Components 4 and 5, part of components 6 and 7 were mixed and dispersed using a three-roll mill.

[0138] B: The remaining components 4 and 5 and components 8 to 11 are uniformly mixed and dispersed at 70°C.

[0139] C: A and B were uniformly dispersed at 70°C.

[0140] D: Components 1 to 3 and part of component 13 were uniformly dispersed at 70°C.

[0141] E: Add C to D and disperse evenly.

[0142] F: Cool E to room temperature.

[0143] G: Component 12 and the remaining component 13 were added to F and mixed to obtain a sunscreen (oil-in-water type).

[0144] (Evaluation method: (a) Moist feeling during application)

[0145] The "moist feeling during application" is defined as (a1) the sample having a certain viscosity or higher and (a2) the friction (average kinetic friction coefficient) between the sample and the applied body during spreading is small, and is judged.

[0146] (a1) Viscosity

[0147] Each prepared sample was allowed to stand at 30°C for 1 day and measured using a Brookfield viscometer (manufactured by Eiko Seiki Co., Ltd.) Each viscosity was evaluated using a No. 4 rotor according to the following two-level evaluation criteria at a measurement time of 6 rpm and 1 minute.

[0148] [Secondary evaluation criteria]

[0149] (Viscosity): (Evaluation)

[0150] 5,000 or more and 10,000 mPa·s or less: A

[0151] Less than 5,000 mPa·s: B

[0152] (a2) Average kinetic friction coefficient

[0153] 0.05 g of each sample was dropped onto a biological skin plate. Using a dynamic friction tester (TRILAB, TL201), 120 reciprocating friction cycles were performed at 100 mm / sec and 200 gf over a distance of 7 cm. The average dynamic friction coefficient for the 20th to 120th strokes was measured and evaluated according to the following three-level evaluation criteria.

[0154] [Three-level evaluation criteria]

[0155] (Average coefficient of kinetic friction): (Evaluation)

[0156] Below 0.5μK: A

[0157] More than 0.5μK and less than 1μK: B

[0158] 1μK or above: C

[0159] Based on the evaluation results of (a1) and (a2), the moist feeling during application was evaluated according to the following three-level evaluation criteria.

[0160] [Level 3 judgment criteria]

[0161] (Evaluation results of a1 and a2): (Judgment)

[0162] When both (a1) and (a2) are rated A: ◎ (Excellent)

[0163] (a1) is evaluated as A and (a2) is evaluated as B, or: ○ (good)

[0164] (a1) is the case of evaluation B and (a2) is the case of evaluation A

[0165] (a1) and (a2) are both rated B, or: × (bad)

[0166] (a2) is the case of evaluating C

[0167] (Evaluation method: (b) No precipitation of solid ultraviolet absorber (5°C / 1M))

[0168] Each sample was placed in a standard glass bottle and stored in a thermostat at 5°C for 1 month (1M). Afterwards, each sample was taken out onto a glass plate and the presence of agglomerates was observed when spread with a finger. The results were evaluated according to the following three-level criteria.

[0169] [Level 3 judgment criteria]

[0170] (Evaluation): (Judgment)

[0171] Almost no aggregates were observed: ◎ (Excellent)

[0172] A small amount of aggregate was observed: ○ (good)

[0173] Many aggregates were observed: × (bad)

[0174] (Evaluation method: (c) Emulsion stability)

[0175] The appearance of each sample immediately after production was observed and judged according to the following three-level judgment standard.

[0176] [Level 3 judgment criteria]

[0177] (Evaluation): (Judgment)

[0178] Almost no separation, very good texture: ◎ (Excellent)

[0179] Almost no separation, good texture: ○ (good)

[0180] Separation occurs, poor texture: × (poor)

[0181] (Evaluation method: (d) Durability)

[0182] Each sample was heated at 2 mg / cm 2 After coating on a PMMA plate (Labsphere, HELIOPLATE HD6), let it stand for 20 minutes, and then use an SPF analyzer (Labsphere, UV-2000S) to measure the SPF of the obtained sample to measure the SPF value before the water bath. Next, a water bath is performed. Regarding the water bath conditions, the sample is attached to the side of a container storing 2L of water at 35°C, and a paddle stirrer is used to stir the water in the container at 300 rpm for 5 minutes. After the water bath is completed, let it stand and dry for 20 minutes, and then use the SPF analyzer to measure the SPF value after the water bath. Based on the ratio of the SPF values before and after the water bath (SPF measured value after the water bath) / (SPF measured value before the water bath), the durability is evaluated according to the following three-level evaluation standard and judged.

[0183] Furthermore, the durability to sweat was evaluated and determined under the same conditions, using simulated sweat instead of water. Here, simulated sweat (pH 5.5) was prepared according to the composition described in ISO (International Organization for Standardization) ISO 105-E04-2008E. It should be noted that in the present invention, durability to water and simulated sweat yielded comparable results, so a comprehensive evaluation was performed as a measure of durability.

[0184] [Level 3 judgment criteria]

[0185] (Ratio (SPF measured value after water bath) / (SPF measured value before water bath)): (Judgment)

[0186] 0.7 or above: ◎ (Excellent)

[0187] 0.5 or more and less than 0.7: ○ (good)

[0188] Less than 0.5: × (bad)

[0189] (Evaluation method: (e) UV protection effect)

[0190] Each sample was heated at 2 mg / cm 2 After coating on a PMMA plate (Labsphere, HELIOPLATE HD6), the sample was left to stand for 20 minutes. The SPF of the resulting sample was measured using an SPF analyzer (Labsphere, UV-2000S). The SPF values were measured at 10 locations on the plate, and the average value was determined according to the following three-level criteria.

[0191] [Level 3 judgment criteria]

[0192] (Average score of ratings): (Judgment)

[0193] 25 and above: ◎ (Excellent)

[0194] 20 or more and less than 25: ○ (good)

[0195] Less than 20: × (bad)

[0196] The results in Tables 1 and 2 show that the sunscreens of Examples 1 to 16 have a moist feel upon application, no precipitation of the solid UV absorber, and are excellent in emulsion stability, durability, and UV protection effect.

[0197] On the other hand, in Comparative Example 1, in which the total content of component (A) and component (B) (A) + (B) exceeded 0.9%, the moist feeling during application and durability may be poor.

[0198] In Comparative Example 2, where the total content of component (A) and component (B) (A) + (B) is less than 0.2%, phase inversion occurs during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0199] In Comparative Example 3, in which the mass ratio (B) / (A) of component (B) to component (A) exceeded 50, phase inversion occurred during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0200] In Comparative Example 4, where the mass ratio (B) / (A) of component (B) to component (A) was less than 1, phase inversion occurred during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0201] In Comparative Example 5, in which a salt-resistant water-soluble polymer (sodium acrylate / sodium acryloyldimethyl taurate) copolymer was used instead of components (A) and (B), the moist feel during application and the durability were sometimes poor.

[0202] In Comparative Example 6, in which a (sodium acrylate / sodium acryloyldimethyl taurate) copolymer was used instead of component (A), phase inversion occurred during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0203] In Comparative Example 7, which does not contain component (B), phase inversion occurred during the production process, resulting in poor emulsion stability, and other effects could not be evaluated in some cases.

[0204] In Comparative Example 8, in which a (sodium acrylate / sodium acryloyldimethyl taurate) copolymer was used instead of component (B), the moist feel during application and the durability were sometimes poor.

[0205] In Comparative Example 9, in which the content of component (C) was less than 15%, the solid ultraviolet absorber precipitated, resulting in a moist feel during application, poor durability, and poor ultraviolet protection effect.

[0206] In Comparative Example 10, in which the content of component (C) exceeded 35%, phase inversion occurred during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0207] In Comparative Example 11, in which the content of component (D) was less than 9%, durability and ultraviolet protection effect were sometimes poor.

[0208] In Comparative Example 12, in which the content of component (D) exceeded 20%, phase inversion occurred during the production process, resulting in poor emulsion stability and in some cases inability to evaluate other effects.

[0209] In Comparative Example 13, in which a metal oxide not subjected to a hydrophobic treatment was used instead of component (D), the moist feel during application and the durability may be poor.

[0210] Example 17: Cream (Oil-in-Water Type)

[0211]

[0212]

[0213] Note 10: MZX-508OTS (average particle size: 25 nm) (manufactured by TAYCA)

[0214] Note 11: SALACOS HS-6C (manufactured by Nisshin Oil Co., Ltd.)

[0215] Note 12: HOSTAPHAT KL340D (manufactured by Clariant Japan)

[0216] Note 13: NIKKOL SMT (manufactured by Nippon Surfactant Industries)

[0217] Note 14: COSMESILICA CQ4 (manufactured by Fuji Silysia Chemical Co., Ltd.)

[0218] (Manufacturing Method)

[0219] A: Components 3 and 4 were mixed and dispersed using a three-roll mill.

[0220] B: A was uniformly dispersed in components 8 to 13 at 70°C.

[0221] C: Components 1, 2, 5, 6, 14 and components 17 to 19 were uniformly dispersed at 70°C.

[0222] D: Add component 7 to C and neutralize.

[0223] E: Add B to D and disperse evenly.

[0224] F: E was cooled to room temperature, and components 15 and 16 were added and uniformly dispersed to obtain a cream (oil-in-water type).

[0225] The cream (oil-in-water type) of Example 17 exhibited a moist feel upon application, emulsion stability, no precipitation of the solid UV absorber, durability, and excellent UV protection. The total content of components (A) and (B), (A) + (B), was 0.48%, and the mass ratio of component (B) to component (A), (B) / (A), was 5.

[0226] Example 18: Liquid foundation (oil-in-water type)

[0227]

[0228] Note 15: SYMPHOLIGHT RW-TE (manufactured by Sunrise Catalysts & Chemicals Co., Ltd., 10% silica)

[0229] Note 16: SYMPHOLIGHT YW-TE (manufactured by Sunrise Catalysts & Chemicals Co., Ltd., 10% silica)

[0230] Note 17: SYMPHOLIGHT BW-TE (manufactured by Sunrise Catalysts & Chemicals Co., Ltd., 10% silica)

[0231] Note 18: TiO2 MP-1133 (manufactured by TAYCA) treated with silica (surface treatment 3.0%)

[0232] Note 19: KSG-15 (manufactured by Shin-Etsu Chemical Co., Ltd.)

[0233] (Manufacturing Method)

[0234] A: Use a three-roll mill to evenly process ingredients 1 to 8.

[0235] B: Component 9 and parts of components 18 and 19 are uniformly processed using a three-roll mill.

[0236] C: Components 10 to 17, the remaining components 18 and 19, and components 20 to 22 are heated to 75°C and uniformly dissolved.

[0237] D: Heat components 23 to 30 to 75°C and mix uniformly.

[0238] E: Mix A and D and heat to 75°C. Add B and C heated to 75°C and emulsify.

[0239] F: Cool E to 50°C.

[0240] G: Add components 31 and 32 to F and mix evenly.

[0241] H: G was cooled to 35°C and filled into a container to obtain a liquid foundation (oil-in-water type).

[0242] The liquid foundation (oil-in-water type) of Example 18 exhibited a moist feel upon application, emulsion stability, no precipitation of the solid UV absorber, durability, and excellent UV protection. The total content of components (A) and (B), (A) + (B), was 0.48%, and the mass ratio of component (B) to component (A), (B) / (A), was 5.

[0243] Example 19: Makeup Base (Oil-in-Water Type)

[0244]

[0245]

[0246] (Manufacturing Method)

[0247] A: Use a three-roll mill to evenly process ingredients 1 to 8.

[0248] B: Component 9 and parts of components 16 and 17 are uniformly processed using a three-roll mill.

[0249] C: Components 21 to 30 were added to A and mixed uniformly at 75°C.

[0250] D: Components 10 to 15, the remaining components 16 and 17, and components 18 to 20 were uniformly mixed at 75°C.

[0251] E: Add B and D to C and emulsify.

[0252] F: Cool E to 40°C.

[0253] G: After filling F into a container, a makeup base (oil-in-water type) is obtained.

[0254] The makeup primer (oil-in-water type) of Example 19 exhibited a moist feel upon application, emulsion stability, no precipitation of the solid UV absorber, durability, and excellent UV protection. The total content of components (A) and (B) (A) + (B) was 0.48%, and the mass ratio of component (B) to component (A) (B) / (A) was 5.

Claims

1. An oil-in-water emulsion composition comprising the following components (A) to (E): (A) (meth)acrylic acid, alkyl (meth)acrylate and (meth)acrylic acid (polyoxyethylene monoalkyl ether) ester copolymer; (B) (Hydroxyethyl Acrylate / Sodium Acryloyldimethyl Taurate) Copolymer; (C) 15-35% by mass of an ester oil that is liquid at 25°C; (D) 9 to 20% by mass of a hydrophobized metal oxide; (E) a UV absorber that is solid at 25°C, in, The total content of the component (A) and the component (B) (A) + (B) is 0.2 to 0.9% by mass. The content mass ratio (B) / (A) of the component (B) relative to the component (A) is 1 to 50.

2. The oil-in-water emulsion composition according to claim 1, wherein The oil-in-water emulsion composition does not substantially contain ethylhexyl methoxycinnamate.

3. The oil-in-water emulsion composition according to claim 1 or 2, wherein The component (A) is an (acrylic acid (ester) / behenyl alcohol polyether methacrylate) copolymer.

4. The oil-in-water emulsion composition according to claim 1 or 2, wherein The component (E) is one or more selected from the following: diethylaminohydroxybenzoyl hexyl benzoate, 2,4-bis{[4-(2-ethylhexyloxy)-2-hydroxy]-phenyl}-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, 4-tert-butyl-4'-methoxydibenzoylmethane, drometrizole trisiloxane, 2-ethylhexyl dimethoxybenzylidenedioxoimidazolidine propionate and 2-hydroxy-4-methoxybenzophenone. The oil-in-water emulsion composition according to claim 1 or 2, further comprising ethanol as a component (F).

6. The oil-in-water emulsion composition according to claim 1 or 2, wherein The oil-in-water emulsion composition contains substantially no surfactant. 7 . The oil-in-water emulsion composition according to claim 1 , which has a viscosity at 30° C. of 5,000 to 10,000 mPa·s.

8. The oil-in-water emulsion composition according to claim 1 or 2, wherein The oil-in-water emulsion composition is a cosmetic for sun protection.

Images