JP2015224240A - Composition containing ultraviolet absorber and ultraviolet scattering agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cosmetic which contains an ultraviolet scattering agent (scattering agent for ultraviolet in UV-A region) dispersed stably for a long period of time, therefore has a high ultraviolet prevention effect, and is excellent in stability, in cosmetics containing an ultraviolet scattering agent and ultraviolet absorber.SOLUTION: Disclosed is a composition containing (A): a scattering agent for ultraviolet in UV-A region, (B): an absorber for ultraviolet in UV-B region, (C): an alkyl-modified carboxyl group-containing polymer obtained by polymerizing 100 parts by mass of (meth) acrylic acid, 0.5-5 parts by mass of (meth) acrylic acid alkyl ester whose carbon number of an alkyl group is 12-24, and 0-0.1 parts by mass of a compound having two or more ethylenic unsaturated groups, and (D): a polymer of ethylenic unsaturated carboxylic acid monomers crosslinked by a water-soluble crosslinker.

Description

  The present invention relates to a composition containing an ultraviolet scattering agent and an ultraviolet absorber. In more detail, this invention relates to the composition (especially cosmetics composition) containing the ultraviolet-ray scattering agent of UV-A area | region, and the ultraviolet absorber of UV-B area | region.

  Since hydrophilic polymers having a carboxyl group, such as carboxyvinyl polymer and alkyl-modified carboxyvinyl polymer, exhibit excellent thickening properties when used in a small amount and provide a refreshing and fresh feeling of use, such as cosmetics and toiletries. It is preferably used as a thickener, dispersant, emulsion stabilizer or the like useful in

  In general, for sunscreen cosmetics, UV scattering agents such as fine particle titanium oxide and fine particle zinc oxide having a scattering effect in the UV-A region (320 to 400 nm), benzophenone compounds, paraaminobenzoic acid compounds, and cinnamic acid compounds. Compounds containing UV absorbers in the UV-B region (280 to 320 nm) such as compounds (see Patent Document 1), 4-tert-butyl-4′-methoxydibenzoylmethane and diethylaminohydroxybenzoyl hexyl benzoate And UV-A region ultraviolet absorbers such as benzophenone compounds, paraaminobenzoic acid compounds, cinnamic acid compounds, and the like (see Patent Document 2). .

  A product blended with an ultraviolet scattering agent has an effect of preventing the sunburn by scattering ultraviolet rays by uniformly dispersing the ultraviolet scattering agent in the product. However, when this is dispersed in cosmetics, a dispersing agent such as a carboxyvinyl polymer or an alkyl-modified carboxy polymer is usually used. However, due to the interaction with these dispersing agents, the UV scattering agent can be used immediately or over time. Aggregation causes problems such as poor emulsification stability or insufficient UV scattering (protection) effect.

  Many proposals have been made so far to prevent aggregation of the ultraviolet scattering agent in the dispersion when the ultraviolet scattering agent is dispersed in the dispersant (for example, Patent Document 1). However, there is a need for further improvement in the suppression of aggregation in the dispersion of the ultraviolet scattering agent and the ultraviolet protective effect.

JP 2002-326906 A JP 2011-046670 A

  An object of the present invention is to contain an ultraviolet scattering agent (ultraviolet scattering agent in the UV-A region) in a composition containing an ultraviolet scattering agent and an ultraviolet absorber and stably disperse for a long period of time. The object is to provide a highly stable composition.

  In the composition containing a UV-A region UV scattering agent and a UV-B region UV absorber, the present inventors cross-linked ethylene with a specific alkyl-modified carboxyl group-containing polymer and a water-soluble cross-linking agent. By using the polymer of the unsaturated unsaturated carboxylic acid monomer, the dispersibility and storage stability of the UV scattering agent are improved, and there is no stickiness or twisting, and it is used well when applied to the skin. The inventors have found that a composition that gives a feeling can be prepared, and have further studied to arrive at the present invention.

That is, the present invention includes, for example, the subject matters described in the following sections.
Item 1.
(A): UV scattering agent in the UV-A region, (B): UV absorber in the UV-B region, and (C): 100 parts by mass of (meth) acrylic acid, and the alkyl group has 12 to 24 carbon atoms. An alkyl-modified carboxyl group-containing polymer obtained by polymerizing 0.5 to 5 parts by weight of (meth) acrylic acid alkyl ester and 0 to 0.1 parts by weight of a compound having two or more ethylenically unsaturated groups; D): A composition containing a polymer of an ethylenically unsaturated carboxylic acid monomer crosslinked by a water-soluble crosslinking agent.
Item 2.
Item 2. The composition according to Item 1, comprising (C) and (D) in a mass ratio (C) :( D) = 20: 80 to 80:20.
Item 3.
Item 3. The compound according to Item 1 or 2, wherein the compound having two or more ethylenically unsaturated groups is at least one selected from the group consisting of pentaerythritol allyl ether, diethylene glycol allyl ether, polyethylene glycol diallyl ether, and polyallyl saccharose. Composition.
Item 4.
Item 4. The composition according to any one of Items 1 to 3, wherein the UV scattering agent in the UV-A region is at least one selected from the group consisting of titanium oxide, zinc oxide, and cerium oxide.
Item 5.
Item 5. The composition according to any one of Items 1 to 4, wherein the ethylenically unsaturated carboxylic acid monomer is at least one selected from the group consisting of acrylic acid and methacrylic acid.
Item 6.
Item 6. The composition according to any one of Items 1 to 5, which is a cosmetic composition.

  With the composition of the present invention, the dispersibility and storage stability of the UV scattering agent in the UV-A region are improved, and furthermore, there is no stickiness or twist, giving a good feeling when applied to the skin. Can do. Therefore, the composition is useful as, for example, a cosmetic or a medicine (particularly a sunscreen cosmetic) (or as a raw material thereof).

The result of having performed the viscosity measurement of the composition (Example 3) concerning this invention and the composition (comparative example 1 and 2) for the comparison using the rheometer is shown.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  The composition according to the present embodiment comprises (A) an ultraviolet scattering agent in the UV-A region, (B) an ultraviolet absorber in the UV-B region, (C) a specific alkyl-modified carboxyl group-containing polymer, and (D) an aqueous solution. And a polymer of an ethylenically unsaturated carboxylic acid monomer cross-linked by an ionic cross-linking agent.

  (A) Examples of the UV scattering agent in the UV-A region include titanium oxide, zinc oxide, and cerium oxide. Titanium oxide is particularly preferable. These are preferably used in the form of fine particles (for example, as fine particle titanium oxide). The ultraviolet scattering agent in the UV-A region can be used alone or in combination of two or more.

  Examples of the ultraviolet absorber in the (B) UV-B region include octyl cinnamate, ethyl-4-isopropyl cinnamate, methyl-2,5-diisopropyl cinnamate, ethyl-2,4-diisopropyl cinnamate, and methyl. -2,4-diisopropylcinnamate, propyl-p-methoxycinnamate, isopropyl-p-methoxycinnamate, isoamyl-p-methoxycinnamate, 2-ethoxyethyl-p-methoxycinnamate, cyclohexyl-p-methoxycinnamate Mate, 2-ethylhexyl-p-methoxycinnamate, ethyl-α-cyano-β-phenylcinnamate, 2-ethylhexyl-α-cyano-β-phenylcinnamate, glyceryl mono-2-ethylhexanoyl-diparamethoxy Such as cinnamate Cinamic acid ultraviolet absorbers; 2,4-dihydroxybenzophenone, 2,2′-dihydroxy-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2 ′, 4,4′-tetra Hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4′-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, 4-phenylbenzophenone, 2-ethylhexyl- Benzophenone ultraviolet absorbers such as 4′-phenyl-benzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone; PABA monoglycerin ester, N, N-dipropoxy PA Paraaminobenzoic acid UV absorbers such as BA ethyl ester, N, N-diethoxy PABA ethyl ester, N, N-dimethyl PABA ethyl ester, N, N-dimethyl PABA butyl ester, N, N-dimethyl PABA methyl ester; Salicylic acid ultraviolet absorbers such as salicylate, menthyl salicylate, homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, p-isopropanol phenyl salicylate; 3- (4′-methylbenzylidene) -d-camphor, 3-benzylidene-d , 1-camphor, urocanic acid, urocanic acid ethyl ester, octyl triazone, 4-methoxy-4′-t-butyldibenzoylmethane and the like. Among these, 2-ethylhexyl-p-methoxycinnamate (also referred to as octyl-p-methoxycinnamate or 2-ethylhexyl 4-methoxycinnamate) is preferable. The ultraviolet absorber of a UV-B area | region can be used individually by 1 type or in combination of 2 or more types.

  The (C) specific alkyl-modified carboxyl group-containing polymer used in the present invention includes (meth) acrylic acid, a (meth) acrylic acid alkyl ester having an alkyl group with 12 to 24 carbon atoms, and further, if necessary. It is obtained by polymerizing a compound having two or more ethylenically unsaturated groups. The polymer is preferably water-soluble. In addition, carbon number of the said (meth) acrylic-acid alkylester becomes like this. Preferably it is 16-24, More preferably, it is 18-24.

  The (meth) acrylic acid alkyl ester having 12 to 24 carbon atoms in the alkyl group refers to an ester of (meth) acrylic acid and a higher alcohol having 12 to 24 carbon atoms in the alkyl group. Examples include esters of (meth) acrylic acid and stearyl alcohol, esters of (meth) acrylic acid and eicosanol, esters of (meth) acrylic acid and behenyl alcohol, and esters of (meth) acrylic acid and tetracosanol. it can. Among these, stearyl methacrylate, eicosanyl methacrylate, behenyl methacrylate and tetracosanyl methacrylate are preferably used. In addition, as a (meth) acrylic-acid alkylester whose carbon number of an alkyl group is 12-24, you may use commercial items, such as brand name Blemmer VMA70 by Nippon Oil & Fats Co., Ltd., for example.

In the present specification, “(meth) acrylic acid” means “methacrylic acid or acrylic acid”. Thus, for example, “(meth) acrylic acid alkyl ester” indicates “methacrylic acid alkyl ester or acrylic acid alkyl ester”.

Combinations of (meth) acrylic acid and (meth) acrylic acid alkyl ester having 12 to 24 carbon atoms in the alkyl group may be combined with each other, or either one or both types. You may combine the above thing together. That is, (
The (meth) acrylic acid alkyl ester can be used alone or in combination of two or more.

  The amount of alkyl (meth) acrylic acid alkyl ester having 12 to 24 carbon atoms in the alkyl group is 0.5 to 5 parts by mass, preferably 1 to 3 parts by mass with respect to 100 parts by mass of (meth) acrylic acid. Part. If the ratio of the (meth) acrylic acid alkyl ester used is less than 0.5 parts by mass, the resulting composition containing the alkyl-modified carboxyl group-containing polymer may not be sufficiently thickened. On the other hand, when the amount exceeds 5 parts by mass, the resulting composition containing the alkyl-modified carboxyl group-containing polymer has a sticky feeling, which may impair the feeling of use particularly when applied to the skin.

  The compound having two or more ethylenically unsaturated groups used as necessary in the present invention is not particularly limited, and examples thereof include pentaerythritol diallyl ether, pentaerythritol triallyl ether, and pentaerythritol tetraallyl ether. Pentaerythritol allyl ether such as diethylene glycol diallyl ether, polyethylene glycol diallyl ether and polyallyl saccharose are preferred. These compounds having two or more ethylenically unsaturated groups may be used alone or in combination of two or more.

  When using the compound which has 2 or more of ethylenically unsaturated groups, the usage-amount is more than 0 mass parts and 0.1 mass parts or less with respect to 100 mass parts of (meth) acrylic acid, 0.001-0 1 part by mass is preferable, and 0.01 to 0.05 part by mass is more preferable.

  Alkyl modification by polymerizing (meth) acrylic acid, (meth) acrylic acid alkyl ester having 12 to 24 carbon atoms in the alkyl group, and, if necessary, a compound having two or more ethylenically unsaturated groups. The method for obtaining the carboxyl group-containing polymer is not particularly limited, and ordinary methods such as a method of stirring these raw materials in a solvent under an inert gas atmosphere and polymerizing using a polymerization initiator can be used. .

  The polymerization method is not particularly limited, and usual emulsion polymerization, suspension polymerization, dispersion polymerization, solution polymerization, precipitation polymerization and the like can be used, and emulsion polymerization, suspension polymerization, dispersion polymerization method, precipitation polymerization are preferable. .

  Examples of the inert gas for obtaining the inert gas atmosphere include nitrogen gas and argon gas.

  The solvent dissolves (meth) acrylic acid, (meth) acrylic acid alkyl ester having 12 to 24 carbon atoms in the alkyl group, and a compound having two or more ethylenically unsaturated groups. There is no particular limitation as long as it does not dissolve the carboxyl group-containing polymer and does not inhibit the reaction. Specific examples of the solvent include normal pentane, normal hexane, normal heptane, cyclopentane, cyclohexane, methyl acetate, ethyl acetate, butyl acetate, and isobutyl acetate. Among these, normal hexane, normal peptane and ethyl acetate are used. It can be used suitably.

  It is preferable that the usage-amount of a solvent is 300-5000 mass parts with respect to 100 mass parts of (meth) acrylic acid from a viewpoint of improving stirring operativity and economical efficiency, for example.

  The polymerization initiator is preferably, for example, a radical polymerization initiator. Specific examples include α, α′-azoisobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, and 2,2 ′. -Azobismethyl isobutyrate etc. can be mentioned. Among these, 2,2'-azobismethylisobutyrate is preferably used from the viewpoint of obtaining a high molecular weight alkyl-modified carboxyl group-containing polymer.

  The amount of the polymerization initiator used is preferably, for example, 0.00003 to 0.002 mol with respect to 1 mol of (meth) acrylic acid. When the amount of the polymerization initiator used is less than 0.00003 mol, the reaction rate becomes slow, which may not be economical. Moreover, when the usage-amount of a polymerization initiator exceeds 0.002 mol, superposition | polymerization advances rapidly and there exists a possibility that control of reaction may become difficult.

  The reaction temperature is preferably 50 to 90 ° C, more preferably 55 to 75 ° C. When the reaction temperature is less than 50 ° C., the viscosity of the reaction solution increases and it may be difficult to stir uniformly. On the other hand, when the reaction temperature exceeds 90 ° C., the reaction proceeds rapidly, and it may be difficult to control the reaction. Since the reaction time varies depending on the reaction temperature, it cannot be generally specified, but is usually 0.5 to 5 hours.

  After completion of the reaction, the alkyl-modified carboxyl group-containing polymer can be obtained by heating the reaction solution to, for example, 80 to 130 ° C. to volatilize and remove the solvent.

  (D) The polymer of an ethylenically unsaturated carboxylic acid monomer cross-linked by a water-soluble cross-linking agent is preferably water-absorbing and may be a water-absorbing resin. That is, (D) is preferably a water absorbent resin containing a polymer of an ethylenically unsaturated carboxylic acid monomer crosslinked by a water soluble crosslinking agent, more preferably a water absorbent resin comprising the polymer. It is.

  As the ethylenically unsaturated carboxylic acid monomer in (D), a water-soluble ethylenically unsaturated carboxylic acid monomer is preferable, and specific examples thereof include acrylic acid and methacrylic acid. An ethylenically unsaturated carboxylic acid monomer can be used individually by 1 type or in combination of 2 or more types. In the present invention, the neutralization degree of the resulting polymer can be easily adjusted by neutralizing the carboxyl group of the ethylenically unsaturated carboxylic acid with an alkali. In the present invention, the degree of neutralization refers to the ratio of the number of moles of neutralized groups to the total number of moles of carboxyl groups in the ethylenically unsaturated carboxylic acid. Examples of the alkali used for neutralization include sodium hydroxide, potassium hydroxide, triethanolamine, diisopropylamine and the like. The neutralization method is not particularly limited, and examples thereof include a method of previously neutralizing an ethylenically unsaturated carboxylic acid monomer and a method of neutralizing a polymer obtained by polymerization.

  Moreover, as a water-soluble crosslinking agent in (D), the compound which has 2 or more of polymerizable unsaturated groups and / or reactive functional groups is mentioned preferably. The reactive functional group is a functional group that can react with the carboxyl group of the ethylenically unsaturated carboxylic acid monomer to form a crosslinked structure. Specific examples thereof include a glycidyl group and an isocyanate group. Examples of the water-soluble crosslinking agent having two or more glycidyl groups include ethylene glycol diglycidyl ether and polyethylene glycol diglycidyl ether. Examples of water-soluble crosslinking agents having two or more polymerizable unsaturated groups include N, N'-methylenebisacrylamide, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and water-soluble sucrose allyl ether. A water-soluble crosslinking agent can be used individually by 1 type or in combination of 2 or more types. Of these, water-soluble sucrose allyl ether is preferably used.

  The degree of etherification of the water-soluble sucrose allyl ether used as the water-soluble crosslinking agent is preferably 2.0 to 3.5, more preferably 2.2 to 3.2. If the degree of etherification of the water-soluble sucrose allyl ether is low, the allyl group, which is a functional group involved in the cross-linking reaction, is insufficient, and the cross-linking reaction tends not to proceed effectively. If the degree of etherification of the water-soluble sucrose allyl ether is high, the solubility in water decreases, so that the cross-linking reaction between the sucrose allyl ether and the ethylenically unsaturated carboxylic acid monomer is difficult to proceed in the aqueous phase. Tend. This degree of etherification is the average value of the molar ratio of allyl ether groups to sucrose. The degree of etherification can be calculated from the amount of acetic anhydride consumed by reacting the hydroxyl group remaining in sucrose allyl ether with acetic anhydride in pyridine.

  The water-soluble sucrose allyl ether can be obtained, for example, by adding sodium hydroxide as a catalyst to an aqueous sucrose solution to convert sucrose to alkaline sucrose and then adding allyl bromide dropwise to perform etherification. it can. At this time, water-soluble sucrose allyl ether is efficiently obtained by adjusting the amount of allyl bromide to a range of preferably 2 to 6 times mol, more preferably 2 to 5 times mol of sucrose. be able to. The etherification reaction temperature is, for example, about 80 ° C. Usually, the reaction is completed in about 3 hours after the addition of allyl bromide. Water-soluble sucrose allyl ether can be recovered by adding alcohol to the aqueous phase separated from the reaction solution, filtering out precipitated salts, and distilling off excess alcohol and water.

  (D) A polymer of an ethylenically unsaturated carboxylic acid monomer cross-linked by a water-soluble cross-linking agent is, for example, a suspension of an ethylenically unsaturated carboxylic acid monomer in the presence of a water-soluble cross-linking agent. It can be obtained by a method including a step of polymerizing by a legal method. Among the suspension polymerization methods, the reverse phase suspension polymerization method in which a polymerization reaction is carried out while dispersing droplets of an aqueous phase containing an ethylenically unsaturated carboxylic acid monomer, a water-soluble crosslinking agent and water in a hydrophobic solvent. Is preferred.

  As the hydrophobic solvent used for the reverse phase suspension polymerization, for example, at least one petroleum hydrocarbon solvent selected from aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons is used. Examples of the aliphatic hydrocarbon include n-pentane, n-hexane, and n-heptane. Examples of the alicyclic hydrocarbon include cyclopentane, methylcyclopentane, cyclohexane, and methylcyclohexane. Aromatic hydrocarbons include benzene, toluene and xylene. In particular, at least one hydrophobic solvent selected from n-hexane, n-heptane, cyclohexane and toluene is suitably used as an industrial general-purpose solvent. The ratio of the hydrophobic solvent is, for example, 100 to 200 parts by mass with respect to 100 parts by mass of the aqueous phase containing the ethylenically unsaturated carboxylic acid monomer and the like.

  In the reverse phase suspension polymerization, the aqueous phase containing an ethylenically unsaturated carboxylic acid monomer or the like, or the hydrophobic solvent may contain other components such as a surfactant and a radical initiator.

  Surfactants are mainly used to stabilize the suspension during polymerization. The surfactant is not particularly limited as long as it is usually used in reverse phase suspension polymerization. Preferably, sorbitan fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, sorbitol fatty acid ester, modified polyethylene wax, modified polypropylene wax, polyvinyl alcohol, polyethylene oxide, cellulose ether (hydroxyethyl cellulose, ethyl cellulose, etc.), sodium alkylbenzene sulfonate, And one or more surfactants selected from polyoxyethylene alkylphenyl ether sulfates.

  The amount of the surfactant is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass with respect to the ethylenically unsaturated carboxylic acid monomer. If the amount of the surfactant is small, there may be a problem in the stability of the suspension state during polymerization, and if the amount of the surfactant is large, it tends to be economically disadvantageous.

  The radical initiator is not particularly limited as long as it is used for normal radical polymerization, but potassium persulfate, ammonium persulfate, sodium persulfate, azo initiators, and the like are preferably used. For example, 2,2'-azobis (2-methylpropionamidine) dihydrochloride can be used as a radical initiator.

  The amount of the radical initiator is preferably 0.01 to 0.5% by mass, more preferably 0.02 to 0.2% by mass with respect to the ethylenically unsaturated carboxylic acid monomer. If the amount of the radical initiator is small, the polymerization reaction tends not to proceed or a long time is required for the reaction. When the amount of the radical initiator is increased, the chain length of the polymer to be produced is shortened, and the viscosity of the aqueous liquid of the water absorbent resin tends to decrease.

  During the reverse phase suspension polymerization, the size of the droplets containing the ethylenically unsaturated carboxylic acid monomer and the like is closely related to the size of the resulting polymer particles. Depending on conditions such as reaction vessel and production scale, for example, when a 2 L flask is used as a reaction vessel, a polymer of an appropriate size can be obtained by carrying out reverse phase suspension polymerization at a stirring speed of 800 to 1000 rpm. It is likely that particles can be obtained. Thus, the size of the polymer particles can be controlled by adjusting the stirring speed during the polymerization reaction. Thus, water-absorbing resin particles having a median particle diameter of preferably about 5 to 30 μm can be obtained. The shape of the polymer particles obtained in this way is spherical and is retained even in an aqueous liquid such as cosmetics, so in cosmetics using this, it has a positive effect on various properties, touch and feel. Conceivable.

  Other conditions for the polymerization reaction, such as the amount of radical initiator, polymerization reaction temperature, reaction time, etc., are also adjusted as appropriate. The polymerization reaction temperature is, for example, 50 to 80 ° C., and the reaction time is, for example, 30 minutes to 3 hours. For example, when a 2 L flask is used as a reaction vessel, the polymerization temperature can be started by adjusting the bath temperature to 60 ° C. In this case, the start of the polymerization reaction can be confirmed from the fact that the temperature in the reaction vessel rises to about 70 ° C. by the polymerization heat. Thereafter, the polymerization reaction is usually completed by conducting an aging reaction for about 30 minutes to 3 hours. If the aging time is shorter than that, the reaction may not be completed sufficiently, and the remaining ethylenically unsaturated carboxylic acid monomer may increase. After the aging reaction, for example, the product can be obtained by elevating the bath temperature and distilling off the water and the petroleum hydrocarbon solvent in the reaction vessel.

  About content of the said component (A)-(D) contained in the composition of this invention, it can set suitably in the range which does not impair the effect of this invention.

  In particular, from the viewpoint that the effects of the present invention can be preferably exhibited, (C) and (D) are preferably included in a mass ratio of (C) :( D) = 20: 80 to 80:20, and (C): (D) = 20: 80 to 70:30 is more preferably included, 20:80 to 50:50 is more preferably included, and 20:80 to 40:60 is even more preferable.

Moreover, about (A) and (B), what is necessary is just to mix | blend with a composition in the range with which an ultraviolet-ray scattering effect and an ultraviolet-ray absorption effect are show | played, respectively. For example, (A) and (B) are preferably included in a mass ratio of (A) :( B) = 30: 70 to 70:30, and (A) :( B) = 40: 60 to 60:40 included More preferably. Moreover, it is preferable that (A) is contained 1 mass% or more with respect to the whole composition, About 1-20 mass% is more preferable, About 2-15 mass% is further more preferable, About 3-10 mass% More preferred. (B) is preferably contained in an amount of 1% by mass or more, more preferably about 1 to 20% by mass, further preferably about 2 to 15% by mass, and more preferably about 3 to 10% by mass with respect to the entire composition. .
In addition, in this specification, the numerical value of content and the content rate about each component which the composition of this invention contains represents the value when not absorbing water (dry mass conversion value) regarding a water absorbing component.

  The composition of the present invention is preferably used as a cosmetic composition. When used as a cosmetic composition, it is particularly preferably used as a sunscreen cosmetic composition. Although the form of cosmetics is not specifically limited, For example, a lotion, a milky lotion, a cosmetic liquid, a foundation, a cream, a cream pack, a gel cream etc. can be illustrated. When the cosmetics according to this embodiment are used as creams, emulsions, gel creams, and emulsified cosmetics, a refreshing feeling and lightness are imparted without causing kinks, and the merit is particularly great.

  In producing the cosmetic composition, known components that are usually used in cosmetics can be further used. Examples of such components include oily components, humectants, surfactants, thickeners, and the like.

  In general, an oil-in-water emulsified cosmetic is produced in a process in which an aqueous phase and an oil phase are heated and dissolved at around 60 ° C., emulsified with a homomixer, and then cooled with stirring. Components (C) and (D) function as a rheology control agent for oil-in-water emulsion cosmetics, an emulsion stabilizer for ultraviolet absorbers, and a dispersant for ultraviolet scattering agents. (C) also functions as a dispersion and emulsion stabilizer for UV scattering agents. The total amount of (C) and (D) is, for example, about 0.1 to 0.3% by mass with respect to all components in a general emulsion, and about 0.2 to 2% by mass in a general cream, for example. In general, when 1% by mass or more is blended, there is an increased risk of stickiness and twisting. However, for products such as ultraviolet absorbers, ultraviolet scattering agents, whitening agents, etc., 0.5 to 2 mass% of components (C) and (D) may be added from the viewpoint of obtaining a desired viscosity. preferable.

  The oil component used in the cosmetic is not particularly limited, but may be natural oil, silicone oil, ester oil, or the like in consideration of the texture to the skin, familiarity, appearance, slipperiness, and the like.

  Examples of natural oils include paraffinic hydrocarbons such as liquid paraffin, olive oil, macadamia nut oil, castor oil, jojoba oil, orange luffy oil, beeswax, lanolin, mineral oil, and squalane.

  Examples of the silicone oil include modified silicone oils such as methylpolysiloxane, methylphenylpolysiloxane, cyclic methylsiloxane, and silicone polyether copolymer.

  Examples of the ester oil include various fatty acid esters. For example, octyldodecyl ester of each fatty acid such as oleic acid, erucic acid, myristic acid, ricinoleic acid is preferable.

  These oily components may be used alone or in combination of two or more.

  The humectant is suitably selected from glycerin, propylene glycol, sorbit, polyethylene glycol, dipropylene glycol, 1,3-butylene glycol, diglycerin, mannitol, POE methyl glycoside, and the like.

  As the surfactant, nonionic glycerin monostearate, POE sorbitan fatty acid ester, sorbitan fatty acid ester, and the like are often used. However, anionic, cationic or amphoteric surfactants can also be used.

  The cosmetic of the present invention may further contain a polysaccharide water-soluble polymer such as hydroxyethyl cellulose and xanthan gum, a carboxyvinyl polymer, and an alkyl-modified carboxyvinyl polymer as a thickener.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

<Synthesis of alkyl-modified carboxyl group-containing polymer A>
(Production Example 1)
In a 500 mL four-necked flask equipped with a stirrer, a thermometer, a nitrogen blowing tube and a cooling tube, 45 g (0.625 mol) of acrylic acid and an alkyl (meth) acrylate having 12 to 24 carbon atoms in the alkyl group Blemmer VMA70 as an ester (manufactured by NOF Corporation: 10-20 parts by mass of stearyl methacrylate, 10-20 parts by mass of eicosanyl methacrylate, 59-80 parts by mass of behenyl methacrylate, and tetracosanyl methacrylate content of 1 1.35 g of a mixture of parts by mass or less), 0.02 g of pentaerythritol allyl ether, 150 g of normal hexane, and 0.081 g (0.00035 mol) of 2,2′-azobismethylisobutyrate were charged. Subsequently, after stirring and mixing uniformly, nitrogen gas was blown into the solution in order to remove oxygen present in the upper space of the reaction vessel, the raw material and the solvent. Subsequently, it was made to react for 4 hours, hold | maintaining at 60-65 degreeC under nitrogen atmosphere. After completion of the reaction, the resulting slurry was heated to 90 ° C. to distill off normal hexane, and further dried under reduced pressure at 110 ° C. and 10 mmHg for 8 hours to obtain water-soluble alkyl-modified carboxyl group-containing white fine powder. 43 g of copolymer A was obtained.

<Synthesis of alkyl-modified carboxyl group-containing polymer B>
(Production Example 2)
A white fine powdery alkyl-modified carboxyl group-containing water-soluble copolymer B43g was obtained in the same manner except that the amount of addition of Blemmer VMA70 (manufactured by NOF Corporation) was changed to 0.45 g in Production Example 1. It was.

<Synthesis of alkyl-modified carboxyl group-containing polymer C>
(Production Example 3)
In Production Example 1, the amount of Blemmer VMA70 (Nippon Yushi Co., Ltd.) was changed to 1.125 g, and 0.135 g of pentaerythritol allyl ether was added. 44 g of an alkyl-modified carboxyl group-containing water-soluble polymer C was obtained.

<Synthesis of water-soluble sucrose allyl ether>
(Production Example 4)
A stirrer, a reflux condenser, and a dropping funnel were attached to a 1000 mL separable flask. In this separable flask, 48 g (1.2 mol) of sodium hydroxide was dissolved in 144 g of water. 136.8 g (0.4 mol) of sucrose was added thereto, and the mixture was stirred at 70 to 85 ° C. for 120 minutes to prepare an alkaline sucrose aqueous solution. To this alkaline sucrose aqueous solution, 145.2 g (1.2 mol) of allyl bromide was added dropwise at 70 to 85 ° C. over 1.5 hours, and then aged at 80 ° C. for 3 hours to obtain sucrose. Was allyl etherified. After cooling, 440 g of water was added, and excess oil was separated with a separatory funnel to obtain a crude sucrose allyl ether aqueous solution. After adjusting the pH to 6-8 by adding hydrochloric acid to this crude sucrose allyl ether aqueous solution, water was removed using a rotary evaporator until the mass of the aqueous solution reached 480 g. Then, 200 g of ethanol was added to precipitate a by-product salt such as sodium bromide, and the precipitate was removed from the aqueous solution by filtration. Further, excess water was removed from the aqueous solution by using an evaporator to obtain 166 g of purified water-soluble sucrose allyl ether having a degree of etherification of 2.4.

<Synthesis of water-absorbent resin (polymer of ethylenically unsaturated carboxylic acid monomer cross-linked by water-soluble cross-linking agent)>
(Production Example 5)
A 500 mL separable flask was equipped with a stirrer, a reflux condenser, and a dropping funnel. In this separable flask, 72 g of acrylic acid and water were put to prepare 90 g of an 80% by mass acrylic acid aqueous solution. While cooling the acrylic acid aqueous solution, 54 g of a 30% by mass aqueous sodium hydroxide solution was added dropwise to neutralize the aqueous solution. Furthermore, 56 g of ion-exchanged water, 0.32 g of water-soluble sucrose allyl ether of Production Example 4 as a crosslinking agent (0.35% by mass with respect to an aqueous acrylic acid solution), and 2,2′-azobis (2 -Methylpropionamidine) dihydrochloride (V-50 manufactured by Wako Pure Chemical Industries, Ltd.) (0.04 g) was added to prepare an ethylenically unsaturated carboxylic acid monomer aqueous solution.

  Separately, 330 g of n-heptane was put into a 2 L separable flask equipped with a stirrer, a reflux condenser, a dropping funnel and a nitrogen gas introduction tube, and sorbitan monostearate (NOF CORPORATION) as a surfactant. (Nonion SP-60R, 2.7 g) was added, and this was dispersed and dissolved in n-heptane. The ethylenically unsaturated carboxylic acid monomer aqueous solution prepared previously was added there. In order to remove oxygen present in the atmosphere, raw materials and solvent in the reaction vessel, nitrogen gas was blown into the solution to replace the system with nitrogen, while the bath temperature was maintained at 60 ° C. and the stirring rate was 1000. Polymerization was carried out by the reverse phase suspension polymerization method over 1 hour with stirring at rotation / min. After completion of the polymerization, water and n-heptane were distilled off to obtain 90 g of water-absorbent resin powder which was a polymer of acrylic acid and its sodium salt and was crosslinked with water-soluble sucrose allyl ether. It was.

<Cosmetics: Preparation of sunscreen cream>
Example 1
After adding components 4-6 to the 60 ° C mixture of components 1-3 below, add the 60 ° C homogeneous mixture of components 7-13 previously prepared while dispersing with a homomixer. (13000 rpm, 5 minutes) was emulsified to prepare a sunscreen cream. In addition,% which shows the following each component amount shows the mass% when the sunscreen cream prepared is set to 100%.

Oil phase Liquid paraffin 10%
2. Isopropyl palmitate 10%
3. 2-ethylhexyl-p-methoxycinnamate 5%
4). Fine particle titanium oxide (Taika MT-100Z) 5%
5. Alkyl-modified carboxyl group-containing polymer A 0.28%
6). Water absorbent resin (prepared in Production Example 5) 0.28%
Aqueous phase 7. Polysorbate 60 3%
8). Glycerin 5%
9. Propylene glycol 5%
10. Ethanol 3%
11. Methylparaben 0.5%
12.6% sodium hydroxide (pH = 6) Purified water residue

(Example 2)
A sunscreen cream was prepared in the same manner as in Example 1 except that the alkyl-modified carboxyl group-containing polymer A was changed to 0.39% and the water-absorbent resin was changed to 0.17%. .

(Example 3)
A sunscreen cream was prepared in the same manner as in Example 1 except that the alkyl-modified carboxyl group-containing polymer A was changed to 0.17% and the water-absorbent resin was changed to 0.39% in Example 1. .

Example 4
A sunscreen cream was prepared in the same manner as in Example 1 except that the alkyl-modified carboxyl group-containing polymer A was changed to B in Example 1.

(Comparative Example 1)
A sunscreen cream was prepared in the same manner as in Example 1 except that the alkyl-modified carboxyl group-containing polymer A was changed to 0% and the amount of the water-absorbent resin added was changed to 0.56%.

(Comparative Example 2)
A sunscreen cream was prepared in the same manner as in Example 1 except that the alkyl-modified carboxyl group-containing polymer A was changed to the alkyl-modified carboxyl group-containing polymer C.

<Characteristic evaluation of cosmetics>
The sunscreen creams obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were evaluated for emulsification stability, titanium oxide dispersibility, viscosity, touch and twist by the following methods. The results are shown in Table 1.

<Emulsion stability>
The prepared emulsion was allowed to stand at room temperature, and the stability after 3 days was visually evaluated.
○: Stable at room temperature for 3 days or more.
X: Separation after 3 days at room temperature.

<Dispersibility of titanium oxide, clay>
The steady flow viscosity was measured with a rheometer under the following measurement conditions to evaluate the dispersibility and viscosity of titanium oxide.

Measurement conditions Rheometer: AR-2000ex manufactured by TA Instruments
Geometry: 60mm Parallel plate Gap: 300μm
Shear rate: 0.001 to 1000 [1 / s] (increase the shear rate gradually)
Measurement temperature: 25 ° C

Dispersibility evaluation of titanium oxide:
○: Measurable up to a shear rate of 1000 [1 / s].
X: The shear rate is lower than 100 [1 / s], and the sample has already protruded and cannot be measured.

  When the dispersibility of titanium oxide is poor, the mixed state becomes poor, so the sample does not follow the measurement at high shear. For this reason, it turns out that the dispersibility of a titanium oxide is bad in the composition in which the viscosity measurement at a high shear rate is impossible. In FIG. 1, the measurement result of each sunscreen of Example 3, the comparative example 1, and the comparative example 2 is shown.

  Viscosity: The viscosity at a shear rate of 3 [1 / s] in the measurement under the above conditions was evaluated as the viscosity of each composition (Table 1).

<Tactile sense>
Tactile sensation was evaluated as follows by 10 testers, 5 men and 5 men each. An appropriate amount of cosmetic was applied to the back of the hand, and the refreshing feeling and lightness when stretched with fingers were evaluated as the texture based on the following criteria.
A: Nine or more of 10 responded that they had a refreshing feeling and lightness.
○: 7 to 8 out of 10 responded that they were refreshing and light.
×: 0 to 6 out of 10 responded that the refreshing feeling and lightness were good.

<Laterity>
The tactile sensation was evaluated as follows by five male and female examiners. When 0.5 g of cosmetic material was taken on the skin and applied to the forearm with a coating time of 1 minute, the occurrence of twists (aggregates) was confirmed.

Evaluation criteria
A: Nine or more of 10 responded that there was no aggregate.
○: 7 to 8 out of 10 responded that there was no aggregate.
X: 0 to 6 out of 10 responded that there was no aggregate.

  The results are shown in Table 1. In addition, the numerical value in the bracket | parenthesis of the "Thickener" column of Table 1 represents mass ratio of each component used as a thickener.

  As shown in Table 1, according to Examples 1 to 3 in which the alkyl-modified carboxyl group-containing polymer and the water-absorbing resin are used in combination, even in a cosmetic containing an ultraviolet scattering agent and an ultraviolet absorbing agent, emulsion stability, A good sunscreen cosmetic with good dispersibility of titanium oxide and a refreshing light tactile feel and smoothness was obtained. It can be seen that the effect of the combined use of the alkyl-modified carboxyl group-containing polymer and the water-absorbent resin is clearly reflected.

Claims (6)

(A): UV scattering agent in the UV-A region, (B): UV absorber in the UV-B region, and (C): 100 parts by mass of (meth) acrylic acid, and the alkyl group has 12 to 24 carbon atoms. An alkyl-modified carboxyl group-containing polymer obtained by polymerizing 0.5 to 5 parts by weight of (meth) acrylic acid alkyl ester and 0 to 0.1 parts by weight of a compound having two or more ethylenically unsaturated groups; D): A composition containing a polymer of an ethylenically unsaturated carboxylic acid monomer crosslinked by a water-soluble crosslinking agent. The composition of Claim 1 which contains (C) and (D) in the ratio of mass ratio (C) :( D) = 20: 80-80: 20. The compound having two or more ethylenically unsaturated groups is at least one selected from the group consisting of pentaerythritol allyl ether, diethylene glycol allyl ether, polyethylene glycol diallyl ether, and polyallyl saccharose. Composition. The composition according to any one of claims 1 to 3, wherein the UV scattering agent in the UV-A region is at least one selected from the group consisting of titanium oxide, zinc oxide, and cerium oxide. The composition according to any one of claims 1 to 4, wherein the ethylenically unsaturated carboxylic acid monomer is at least one selected from the group consisting of acrylic acid and methacrylic acid. The composition according to any one of claims 1 to 5, which is a cosmetic composition.

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