JP4515168B2 - Water-in-oil emulsified cosmetic - Google Patents

Description

  The present invention relates to a water-in-oil (W / O) emulsified cosmetic having good adhesion to the skin, makeup persistence, and applicability to the skin.

  Conventionally, cosmetics containing a film-forming polymer have been known in order to obtain cosmetics with excellent water resistance, oil resistance or abrasion resistance, and high makeup durability. Acrylic polymers are used as film-forming polymers. Etc. are blended.

  For example, Patent Document 1 discloses a makeup cosmetic containing a non-emulsifier polymerized resin emulsion that does not use an emulsifier during polymerization. Patent Document 2 discloses a makeup cosmetic in which a copolymer polymer emulsion obtained from an acrylate ester monomer having 4 to 18 carbon atoms in the ester portion and a methacrylic ester monomer is blended. Furthermore, Patent Document 3 discloses a polymer emulsion obtained from an acrylic ester monomer having 4 to 18 carbon atoms in the ester portion and a methacrylic ester monomer having 1 to 4 carbon atoms in the ester portion, and a glycol such as propylene glycol. A makeup cosmetic containing the above is disclosed. Patent Document 4 discloses a makeup cosmetic containing a polymer composed of an acrylic ester and a polymerizable carboxylic acid, the main component of which is an acrylic ester having 1 to 3 carbon atoms in the ester portion. Patent Document 5 discloses a film-forming foundation water-in-oil emulsion containing a water-soluble or dispersible film-forming polymer and a plasticizing solvent in an aqueous internal phase.

These technologies improve the adhesion of the cosmetic film to the skin and the factors related to makeup durability such as water resistance and oil resistance by blending a film-forming polymer, and in some cases combine specific polyols Although the cosmetic film is made softer and flexible, the adhesion to the skin is improved by blending the film-forming polymer. On the other hand, the polymer alone or the polymer and the powder are formed on the skin at the time of application. There is a problem in that an eraser-cass-like aggregate is formed, or the spreadability of the agent is lowered and unevenness is likely to occur. In addition, even if the film-forming polymer itself is excellent in adhesion to the skin and flexibility, when the powder and polymer become a single decorative film, the powder and polymer like a fiber reinforced plastic The combined effect increases the rigidity of the decorative film, and the flexibility of the polymer is often less likely to be exhibited. In addition, the addition of a polyol having a plasticizing effect on the polymer has the effect of improving the flexibility and cleansing properties of the decorative film, but the makeup sustainability, which is the original purpose of the polymer formulation, is reduced, and the effect of blending the polymer is reduced. It drops significantly. Further, when the continuity of the polymer film is increased, the adhesion of powder such as powder foundation and teak in the decorative film is different from that of the skin, and an unnatural finish is likely to occur. Furthermore, the stability of the emulsion is not sufficiently satisfactory.
JP 54-49338 A JP 54-151139 A JP-A-1-203313 Japanese Patent No. 3072568 Japanese National Patent Publication No. 11-504326

  The problem of the present invention is that the adhesiveness to the skin, the makeup persistence, and the applicability to the skin are good, and it does not form an eraser debris agglomerate on the skin at the time of application, and the blending stability of the emulsion Another object of the present invention is to provide a water-in-oil emulsified cosmetic excellent in water resistance.

The present invention provides a water-in-oil emulsified cosmetic containing the following components (A) and (B).
Component (A): (meth) acrylic acid or salt thereof / (meth) alkyl acrylate (alkyl group having 3 or 4 carbon atoms) / methyl (meth) acrylate copolymer, its glass transition temperature (Tg) A soap-free polymer emulsion component (B) containing a polymer having a temperature of −45 to −15 ° C .: a powder having an average particle size of 0.1 to 50 μm In this specification, “soap-free polymer emulsion” means an interface It refers to a polymer emulsion that does not contain an emulsifier such as an activator, a polymer emulsifier (nonionic, anionic, cationic) or a reactive surfactant.

  Moreover, in this specification, "(meth) acrylic acid" is a concept including both acrylic acid and methacrylic acid.

  The cosmetics of the present invention have excellent adhesion to the skin and long-lasting makeup, good applicability to the skin, no stickiness or stickiness, and generation of an eraser residue on the skin during application. In addition, the emulsion stability of the blend is also good.

[Component (A): Soap-free polymer emulsion]
The polymer constituting the soap-free polymer emulsion of the present invention comprises (meth) acrylic acid or a salt thereof / (meth) alkyl acrylate (alkyl group having 3 or 4 carbon atoms) / methyl (meth) acrylate copolymer. (Meth) acrylic acid or a salt thereof / (meth) acrylic acid n-butyl / (meth) methyl acrylate copolymer is preferable, and acrylic acid or a salt thereof / n-butyl acrylate / methyl methacrylate copolymer is preferable. Further preferred.

  The ratio of (meth) acrylic acid or a salt thereof to the total monomer components constituting this copolymer is preferably 0.1 to 10% by weight, and more preferably 1 to 5% by weight. The proportion of alkyl (meth) acrylate (C3 or C4 alkyl group) is preferably from 64 to 91% by weight, more preferably from 70 to 85% by weight. The proportion of methyl (meth) acrylate is preferably 0.1 to 35.9% by weight, more preferably 4 to 30% by weight.

  The method for producing a soap-free polymer emulsion of the present invention comprises emulsion polymerization of the above monomer components in the presence of a polymerization initiator without using an emulsifier such as a surfactant, a polymer emulsifier, a reactive surfactant, etc. Is preferred. In the case of emulsion polymerization, the main component of the solvent used is water, and in some cases, a hydrophilic solvent such as a lower alcohol may be mixed. The reaction temperature is set below the boiling point of the solvent. The monomer concentration in the reaction system is not particularly limited, but is preferably 1 to 60% by weight from the viewpoint of production efficiency and aggregation suppression.

  The amount of the polymerization initiator is not particularly limited, but is preferably 0.01 to 10 parts by weight with respect to 100 parts by weight of the monomer from the viewpoint of economy and reduction of the residual monomer amount. The monomer (or monomer solution) may be polymerized after being previously mixed in a solvent containing water as a main component, or may be polymerized while dropping. Similarly, the polymerization initiator (or polymerization initiator solution) may be mixed in advance in a solvent containing water as a main component, or may be dropped.

Examples of the polymerization initiator used in the present invention include organic polymerization initiators such as hydroperoxides, peroxides, and azo compounds, and inorganic polymerization initiators such as potassium persulfate, sodium persulfate, and ammonium persulfate. Can be mentioned. A so-called redox polymerization initiator using a reducing agent such as sodium bisulfite, ascorbic acid or a salt thereof in combination with a polymerization initiator can also be used.
In the polymerization, a polymerization chain transfer agent such as mercaptans may be further added.

  The glass transition temperature (Tg) of the polymer constituting the polymer emulsion of the present invention is −45 to −15 ° C., more preferably −40 to −25 ° C. from the viewpoint of obtaining a good feeling of use and a finished feeling.

  In the present specification, Tg is a value measured by the following measuring method.

<Tg measurement method>
The Tg of the film after drying the polymer emulsion under reduced pressure is measured using a differential scanning calorimeter (DSC) under the following measurement conditions.

Using a DSC6200 (software EXSTAR6000 thermal analysis rheology system) manufactured by Seiko Instruments Inc., the temperature program consists of the following four stages, and Tg was determined from the curve obtained in the third stage.
・ First stage: temperature rise at 20 ° C. → 20 ° C./min→hold at 100 ° C. for 1 minute ・ Second stage: temperature drop at 100 ° C. → 200 ° C./min→hold at −120 ° C. for 10 minutes ・ third stage: − 120 ° C. → Temperature rise at 10 ° C./min→Hold at 100 ° C. for 1 minute. Fourth stage: 100 ° C. → Temperature drop at 20 ° C./min→Hold at 20 ° C. for 2 minutes.

  The average particle size of the polymer in the polymer emulsion of the present invention is preferably 0.01 to 1.5 μm, more preferably 0.2 to 1.0 μm, and particularly preferably 0.3 to 0.8 μm. The average particle diameter of the polymer is a value measured by the following method.

<Measuring method of average particle size>
The average particle size of the polymer in the polymer emulsion was measured at a refractive index of 1.2 using a laser diffraction / scattering particle size distribution analyzer LA-910 (Horiba, Ltd.). In the measurement, the prepared polymer emulsion was dispersed using ion-exchanged water as a dispersion medium, and the particle size distribution was measured at a laser transmittance of 75 to 90%.

  The polymer concentration of the polymer emulsion of the present invention is preferably 20 to 60% by weight, more preferably 40 to 55% by weight.

[Component (B): Powder]
The powder used in the present invention may be any powder used as a cosmetic powder, and specifically, silica, aluminosilicate, zeolite, barium sulfate, boron nitride, alumina, titanium dioxide, talc. , Inorganic powders such as mica, synthetic phlogopite, titanium mica; silicone resin, polyethylene resin, urethane resin, poly (meth) acrylate ester copolymer, polyamide resin, polyester resin, polypropylene resin, polystyrene resin, urea resin , Phenolic resin, fluorine resin, melamine resin, epoxy resin, polycarbonate resin, divinylbenzene / styrene copolymer, silk powder, organic powder such as cellulose powder; coloring pigments such as iron oxide, zinc oxide, chromium oxide, etc. It is done. In addition, these powders containing cosmetic oils, ultraviolet absorbers and the like, and those obtained by combining these powders can also be used.

  As the shape of these powders, powders having various shapes such as a spherical shape, a substantially spherical shape, a plate shape, and a needle shape can be used. Moreover, the average particle diameter of powder is 0.1-50 micrometers from a viewpoint of obtaining favorable applicability | paintability and emulsion stability, and 1-15 micrometers is preferable.

  Here, the average particle diameter of the powder indicates a volume average particle diameter, that is, an average value of the diameters of the volume-corresponding spheres of the measured particles, and a value obtained by laser diffraction using ethanol as a dispersion medium is used.

  The surface of the powder may be hydrophobized from the viewpoint of improving makeup sustainability. The hydrophobizing treatment is performed by treating with a hydrophobizing agent according to a normal method. Examples of hydrophobizing agents include silicone oil, fatty acid metal salt, alkyl phosphoric acid, alkali metal salt or amine salt of alkyl phosphoric acid, N-mono long chain (carbon number 8 to 22) aliphatic acyl basic amino acid, perfluoro Examples thereof include fluorine compounds having an alkyl group. Examples of silicone oils include various chain silicones, cyclic silicones, and modified silicones; examples of fatty acid metal salts include salts of fatty acids having 12 to 18 carbon atoms such as calcium, magnesium, zinc, and aluminum; alkylphosphoric acid and its Examples of the salt include mono- or diesters having an alkyl or alkenyl group having a total carbon number of 8 to 45, and alkali metal salts or amine salts; , Lauroyl, myristoyl, palmitoyl, stearoyl, isostearoyl, oleoyl, behenoyl, cocoyl, beef tallow fatty acid acyl, hard beef tallow fatty acid acyl, etc. Is bonded to a perfluoroalkyl group Examples of the fluorine compound having the above are those described in U.S. Pat. No. 3,632,744, JP-A-62-250074, JP-A-55-167209, JP-A-2-218603, and the like.

  The hydrophobizing amount of the powder is 0.0005 to 0.2 parts by weight, particularly 0.02 to 0.2 parts by weight, based on 1 part by weight of the powder, from the viewpoint of sufficient hydrophobicity and good touch. 1 part by weight is preferred.

[Water-in-oil emulsified cosmetic]
The method for producing the water-in-oil emulsified cosmetic of the present invention is not particularly limited, but after adding and dispersing the component (B) in the oil phase, the aqueous phase containing the component (A) is added and emulsified. Is preferred.

  By using a water-in-oil emulsified cosmetic, it becomes possible to efficiently adsorb the component (A) to the component (B), and further, a finish without a feeling of tension is obtained. Moreover, the cosmetics with high stability can be obtained by soap-free polymerization of the component (A).

  The content of the component (A) in the cosmetic of the present invention is preferably 0.1 to 40% by weight in terms of solid content in all cosmetics from the viewpoint of obtaining a good feeling of use and a finish, More preferred is ˜20% by weight. The content of the component (B) in the cosmetic of the present invention is preferably from 0.5 to 40% by weight, more preferably from 1 to 30% by weight, from the viewpoint of obtaining a good feeling of use and a finishing feeling. The ratio of the component (A) to the total amount of the component (A) and the component (B) is a weight ratio, (A) / [(A) + (B)] = 0.01 to 0.85, 0.015 to 0.55 is preferable from the viewpoint of obtaining a good feeling of use and a feeling of finish.

  The cosmetic of the present invention can further contain a surfactant as the component (C). As the surfactant, a nonionic surfactant having an HLB of 1 to 6 is preferable. Examples of the nonionic surfactant having an HLB of 1 to 6 include monoglyceride, sorbitan fatty acid ester, sucrose fatty acid ester, polyglycerin fatty acid ester, alkanolamide, amine oxide, polyoxyethylene alkyl ether, polyethylene glycol fatty acid ester, poly Oxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin mono fatty acid ester, polyoxyethylene propylene glycol mono fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyethylene fatty acid amide, polyoxyethylene alkylamine, alkyl saccharide, α-monoalkyl glyceryl Ether, dimethylpolysiloxane / polyoxyalkylene copolymer, dimethylpolysiloxane / monoalkylglyceryl Ether copolymer (see JP-A-6-135871) and the like. Among them, sorbitan fatty acid ester, polyoxyethylene alkyl ether, α-monoalkyl glyceryl ether, dimethylpolysiloxane / polyoxyalkylene copolymer, dimethylpolysiloxane / monoalkylglyceryl ether copolymer are preferable, and dimethylpolysiloxane / Polyoxyalkylene copolymers and dimethylpolysiloxane / monoalkyl glyceryl ether copolymers are more preferred. 1 type, or 2 or more types can be used for this surfactant. The HLB value here is based on the Gluffin method.

  The amount of component (C) in the cosmetic of the present invention is preferably 0.05 to 10% by weight, more preferably 0.1 to 8% by weight, and still more preferably 0.3 to 5% by weight. Within this range, a stable water-in-oil emulsified cosmetic can be obtained, no stickiness is produced during use, and the feeling in use is good.

  The cosmetic of the present invention may further contain an oil agent as component (D). Oils include silicone oils such as dimethylpolysiloxane, cyclic silicone, alkyl-modified silicone and fluorine-modified silicone, hydrocarbon oils such as isoparaffin and squalane, ester oils such as isopropyl myristate, and fluorine oils such as fomblin. Oils that can be used in the preparation are listed. The blending amount of the component (D) in the cosmetic of the present invention is preferably 5 to 60% by weight, and more preferably 10 to 50% by weight from the viewpoint of obtaining a good feeling of use and a finishing feeling.

  Furthermore, the cosmetic of the present invention may contain an aqueous solvent such as a lower alcohol having 1 to 3 carbon atoms such as ethanol and isopropyl alcohol.

  Moreover, a moisturizer can be mix | blended with the cosmetics of this invention. As the humectant, polyhydric alcohols such as glycerin, 1,3-butylene glycol, propylene glycol, dipropylene glycol, diglycerin, isopropylene glycol, 1,2-pentanediol, xylit, sorbit, polyethylene glycol, and polyethylene glycol And humectants such as glycine betaine, xylitol, trehalose, urea and amino acids. The blending amount of the humectant in the cosmetic of the present invention is preferably 0.1 to 10% by weight, and more preferably 1 to 5% by weight from the viewpoint of obtaining a good feeling of use and a feeling of finish.

  The cosmetic of the present invention can further contain a water-soluble salt as an emulsion stabilizer. Examples of water-soluble salts include sodium citrate, sodium L-glutamate, potassium acetate, sodium acetate, magnesium acetate and other lactate salts, sodium carbonate, aluminum lactate, calcium lactate, and other sulfates, magnesium sulfate, sodium sulfate, and other sulfates. And phosphates such as sodium monofluorophosphate and disodium hydrogen phosphate. These water-soluble salts are preferably added after being dissolved in water. The amount of the water-soluble salt in the cosmetic of the present invention is preferably 0.05 to 3% by weight, more preferably 0.1 to 2.0% by weight.

  The cosmetics of the present invention further include ingredients generally used as cosmetic ingredients within a range not impairing the effects of the present invention, for example, water-soluble polymers such as xanthan gum, hydroxyethyl cellulose, methyl cellulose, hydroxypropyl guar gum, glycyrrhizin Water-soluble medicinal agents such as acid salts and vitamins, pH buffering agents such as citric acid, succinic acid, and trisodium citrate, preservatives such as methylparaben, UV absorbers, chelating agents, dyes, pigments, and fragrances are appropriately added. be able to.

  The cosmetics of the present invention are makeup cosmetics such as various foundations, makeup bases, eye shadows, eye liners, eyebrows, mascara, nail enamels, skin cosmetics such as packs, lipsticks, cheeks, sunscreens, hair It can be widely applied to cosmetics, medicinal cosmetics, etc., and is particularly preferably used as a foundation or makeup base.

  In the examples, “%” means “% by weight” unless otherwise specified.

Synthesis example 1
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution in which 0.5 g of ammonium persulfate was dissolved in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. The dropping funnel was charged with 97 g of n-butyl acrylate and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. The emulsion was dried to form a film and measured by DSC. As a result, Tg was -51 ° C.

Synthesis example 2
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution in which 0.5 g of ammonium persulfate was dissolved in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. The dropping funnel was charged with 6 g of methyl methacrylate, 91 g of n-butyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. The emulsion was dried to form a film and measured by DSC. As a result, Tg was -45 ° C.

Synthesis example 3
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution prepared by dissolving 0.55 g of ammonium persulfate in 5 g of ion-exchanged water, nitrogen gas was passed to remove dissolved oxygen. A dropping funnel was charged with 16 g of methyl methacrylate, 81 g of n-butyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. As a result of measuring the dried and film-formed emulsion by DSC, Tg was -35 ° C.

Synthesis example 4
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution of 2 g of sodium polyoxyethylene lauryl ether sulfate and 0.5 g of potassium persulfate in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. A dropping funnel was charged with 16 g of methyl methacrylate, 81 g of n-butyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. As a result of measuring the dried and film-formed emulsion by DSC, Tg was -35 ° C.

Synthesis example 5
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution in which 0.5 g of ammonium persulfate was dissolved in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. A dropping funnel was charged with 33 g of methyl methacrylate, 64 g of n-butyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. As a result of measuring what dried this emulsion and made it into a film by DSC, Tg was -15 degreeC.

Synthesis Example 6
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution in which 0.5 g of ammonium persulfate was dissolved in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. A dropping funnel was charged with 37 g of methyl methacrylate, 60 g of n-butyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. As a result of measuring what dried this emulsion and made into a film by DSC, Tg was -10 degreeC.

Synthesis example 7
175 g of ion-exchanged water was put in the reaction vessel, and the temperature was raised to 70 to 80 ° C. After adding a solution in which 0.5 g of ammonium persulfate was dissolved in 5 g of ion-exchanged water, the dissolved oxygen was removed by flowing nitrogen gas. A dropping funnel was charged with 16 g of methyl methacrylate, 81 g of 2-ethylhexyl acrylate, and 3 g of acrylic acid. The temperature of the reaction vessel was raised to 80 ° C. with stirring, and the monomer was added dropwise from a dropping funnel over 3 hours, followed by aging for 3 hours. After cooling, 35% of acrylic acid was neutralized with an aqueous NaOH solution, and the pH was adjusted to 4-8. After pH adjustment, a certain amount of ion-exchanged water was added and topping was performed to remove residual monomers and deodorization to remove some aggregates to obtain a polymer emulsion having a solid content of 50%. As a result of measuring the dried and film-formed emulsion by DSC, Tg was -35 ° C.

Examples 1-3 and Comparative Examples 1-4
Using the polymer emulsions obtained in Synthesis Examples 1 to 7, W / O emulsified cosmetic bases having the compositions shown in Table 1 were prepared by the following method. About the obtained makeup | decoration base | substrate, the following feeling evaluated the usability, the finish, and the stability of the W / O emulsion. The results are shown in Table 2.

<Preparation method of makeup base>
(9) to (13) in Table 1 previously mixed and pulverized are added to the oil phase in which (1) to (3) are mixed at room temperature, dispersed with a disper, and pre-water phase components A mixture of (4) to (8) was added with stirring and emulsified to prepare a W / O emulsified cosmetic base.

<Evaluation method>
About the prepared makeup base, feeling of use (ease of scum when applied, stickiness, tension, followability to the skin), finish (natural finish, lack of powderiness, uniformity (no unevenness) ), The finish of the powder cosmetic, and the makeup durability) and the stability of the W / O emulsion (stored at 40 ° C. and 75% humidity for half a year). Evaluation of the naturalness of the finish, lack of powderiness, and uniformity (non-uniformity) immediately after application to the skin, and for makeup holders, 4 hours after application (in the normal living environment indoors) Evaluated. The evaluation was performed by 10 expert panelists for each item according to the evaluation criteria shown in Table 3, and the average value of 10 persons was calculated.

* 1: The following abbreviations were used for monomers.
BA: n-butyl acrylate AA: acrylate MMA: methyl methacrylate 2EHA: 2-ethylhexyl acrylate

Examples 4-6 and Comparative Examples 5-8
Using the polymer emulsions obtained in Synthesis Examples 1 to 7, W / O emulsified liquid foundations having the compositions shown in Table 4 were prepared by the following method. About the obtained liquid foundation, the usability, finish, and stability of the W / O emulsion were evaluated in the same manner as in Example 1. The results are shown in Table 5.

<Preparation method of liquid foundation>
(9) to (18) in Table 4 previously mixed and pulverized are added to the oil phase in which (1) to (3) are mixed at room temperature, dispersed with a disper, and pre-water phase components A mixture of (4) to (8) was added with stirring and emulsified to prepare a W / O emulsified liquid foundation.

Claims (3)

Water-in-oil emulsified cosmetic component (A) containing the following component (A) and component (B): (meth) acrylic acid or a salt thereof / alkyl (meth) acrylate (alkyl group having 3 or 4 carbon atoms) ) / (Meth) methyl acrylate copolymer, its glass transition temperature (Tg) is −45 to −25 ° C., alkyl (meth) acrylate (with 3 or 4 carbon atoms) for all monomer components constituting the polymer. Soap-free polymer emulsion component (B) containing a polymer having a ratio of alkyl group) of 70 to 91% by weight : powder having an average particle size of 0.1 to 50 μm In proportion by weight of components (A) component (A) and the total amount of the components (B), (A) / [(A) + (B)] = a .01 to .85 claim 1 The water-in-oil emulsified cosmetic described. The water-in-oil emulsified cosmetic according to claim 1 or 2 , wherein the component (B) is a hydrophobized powder.