JP2001294513A - Cosmetics - Google Patents

Abstract

(57) [Summary] PROBLEM TO BE SOLVED: To provide excellent soft focus effect and transparency.
Get cosmetics. SOLUTION: The average particle diameter (μm) is D and each layer is constituted.
The refractive index of the polymer _k(Possible outermost layer
The refractive index of the limer is n₁And the other layers
The refractive index of the mer, n_Two, N_Three,
..N_k(K is an integer of 2 to 10)],
formula: 0.5 ≦ D ≦ 100 (I) 1.3 ≦ n_k≦ 1.7 (II) │n_Two-N₁│ ≧ 0.05 (III) Containing spherical particles having a multilayer structure that satisfies
The above-mentioned problems are solved by a cosmetic composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to cosmetics containing spherical particles having a multilayer structure. More specifically, the present invention relates to a cosmetic containing spherical particles having a multilayer structure in which each layer is composed of a polymer having a different refractive index.

[0002]

2. Description of the Related Art Cosmetics containing cosmetic powder include:
There are makeup cosmetics such as foundation, white powder, blusher, eye shadow, etc., body cosmetics such as body powder and baby powder, lotion cosmetics such as pre-shave lotion, body lotion, etc., to improve elongation and feel on the skin, For the purpose of providing a wrinkle concealing effect, spherical particles such as crosslinked polystyrene particles, nylon particles, and polymethyl methacrylate particles are blended. In recent years, by making spherical particles a multilayer structure,
Spherical particles provided with a new function have been proposed.

In Japanese Patent Application Laid-Open No. H11-92534, a soft feeling is imparted to a core material having elasticity similar to that of rubber by forming a methacrylate-based resin on the surface of the core material while keeping the characteristics of spherical particles. Cosmetics have been proposed. In JP-A-7-291837, a layer made of an acrylic or styrene-based resin not containing an organic ultraviolet absorber is provided on the surface of particles containing an organic ultraviolet absorber in an acrylic or styrene-based resin. Cosmetic particles which are formed and suppress skin irritation due to elution of an ultraviolet absorber have been proposed. In addition, Japanese Unexamined Patent Publication No.
JP 103510 proposes a makeup cosmetic having improved friction resistance by blending polymer particles with an aqueous composite polymer emulsion having a multilayer structure composed of at least two layers having different compositions. Also, in JP-A-6-239718,
Cosmetic has a core-shell structure composed of a specific monomer and composed of a core part and a shell part. By blending a resin higher than the glass transition point of the core part in the shell part, it has friction resistance and objective adhesion. Makeup cosmetics with improved properties have been proposed.

[0004]

However, single particles such as nylon particles and polymethyl methacrylate particles do not have a sufficient soft focus effect, and particles having a high refractive index such as cross-linked polystyrene particles do not have a sufficient soft focus effect. Although a soft focus effect can be imparted, there is a problem that the skin looks whitish at the time of finishing because of the concealment effect. Further, the above-mentioned particles having a multilayer structure are mainly intended to improve the feeling of use of the cosmetic, and are not satisfactory in terms of imparting a soft focus effect or transparency. The present invention has been made in view of such circumstances, and has as its object to provide a cosmetic composition that improves elongation on skin and transparency, and that has an excellent soft focus effect.

[0005]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a multilayer structure having a specific average particle diameter and a plurality of layers having different refractive indices. Surprisingly, cosmetics containing spherical particles of
The present inventors have found that the present invention is excellent in elongation and transparency on the skin and has an excellent soft focus effect, and has completed the present invention. Thus, according to the present invention, the average particle size (μ
m) is D, the refractive index of the polymer constituting each layer is _nk [the refractive index of the polymer constituting the outermost layer is n _1, and the refractive index of the polymer constituting each layer is in order toward the inside of the particle. where n ₂ , n ₃ ,..., _nk (k is an integer of 2 to 10)], the expression: 0.5 ≦ D ≦ 100 (I) 1.3 ≦ _nk ≦ 1.7 ( II) A cosmetic is provided, which comprises spherical particles having a multilayer structure satisfying | n ₂ −n ₁ | ≧ 0.05 (III).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The spherical particles having a multilayer structure used in the present invention have an average particle diameter of D (μm) and a refractive index of a polymer constituting each layer is _nk [of a polymer constituting an outermost layer]. The refractive index is defined as n _1, and the refractive indices of the polymers constituting each layer are sequentially set to n ₂ , n ₃ ,.
_Nk (k is an integer of 2 to 10)], the following formulas (I) to (III) are satisfied. 0.5 ≦ D ≦ 100 (I) 1.3 ≦ _nk ≦ 1.7 (II) │n ₂ −n ₁ │ ≧ 0.05 (III) If _nk is smaller than 1.3, light scattering Since the effect is small, it is not preferable because a sufficient soft focus effect cannot be imparted to the cosmetic when incorporated into the cosmetic. On the other hand, if _nk exceeds 1.7, the light scattering effect becomes too large, and when incorporated into cosmetics, the transparency is impaired, which is not preferred.

If | n ₂ −n ₁ | is smaller than 0.05, the light scattering effect is reduced, and when incorporated in a cosmetic, a sufficient soft focus effect cannot be imparted to the cosmetic. Therefore, it is not preferable. The spherical particles having a multilayer structure used in the present invention more preferably satisfy the following formula. _{n 2 -n 1 ≧ 0.05 (IV} ) n x -n x-1> 0 (V) ( here, x is an integer of 3～K) Then, the refractive index of each layer, the center of the spherical particles Increasing the size gradually increases the reflection of light from the cosmetic and further improves the transparency, which is preferable. Therefore, the spherical particles having a multilayer structure used in the present invention more preferably satisfy the following formula. _{n x -n x-1 <n} x-1 -n x-2 (VI) ( here, x is an integer of 3～K) thereon, the difference in the refractive index of the polymer constituting the adjacent layers, It is particularly preferable that the particle size is gradually reduced toward the center of the particles because the reflection of the light of the cosmetic is further reduced and the transparency is further improved.

The refractive index referred to here is obtained by measuring a plate made of the same polymer as the polymer constituting each layer with a refractometer. Equation (II) above
The polymer having a refractive index that satisfies is not particularly limited, but includes, for example, a (meth) acrylate resin, a styrene resin, a polyamide resin, a polyolefin resin, a cellulose resin, a silicon resin, a fluorine resin, and the like. Is mentioned. Among these polymers, a styrene-based resin is preferable as the polymer constituting the innermost layer (hereinafter referred to as a core) of the particles, and a (meth) acrylate-based resin is particularly preferable as the polymer constituting the coating layer. The polymer constituting the core may contain an inorganic compound as long as the effect of the present invention is not impaired. Examples of the inorganic compound include titanium oxide, zinc oxide, zirconium oxide, silica, barium sulfate, calcium carbonate and the like. As the spherical particles having a multilayer structure used in the present invention, for example, spherical particles having a two-layer structure in which a nucleus is formed of a styrene-based resin and a coating layer is formed of a (meth) acrylate-based resin are low in production cost. It is particularly preferred in that respect.

Examples of the monomer forming the styrene resin include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene and octyl styrene. Alkyl styrenes such as fluorostyrenes, chlorostyrenes, bromostyrenes, dibromostyrenes, halogenated styrenes such as iodostyrenes and chloromethylstyrenes; and nitrostyrenes.
Acetyl styrene and methoxy styrene are exemplified.

The monomer forming the (meth) acrylate resin is, for example, methyl (meth)
Acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate,
2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-propyl (meth) acrylate, chloro-2-hydroxy Ethyl (meth) acrylate, diethylene glycol mono (meth)
Acrylate, methoxyethyl (meth) acrylate,
Examples include glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and isoboronor (meth) acrylate. The styrene-based resin and the (meth) acrylate-based resin are preferably homopolymers of the above-described monomers, respectively. If the resins satisfy the above-mentioned formulas (II) and (III), two types of resins may be used. A copolymer composed of the above monomers may be used. In the styrene-based resin and the (meth) acrylate-based resin, each of the above monomers may be copolymerized with a difunctional or polyfunctional monomer.

Examples of the bifunctional or polyfunctional styrenic monomer include divinylbenzene.
Examples of the acrylate-based monomers include ethylene glycol di (meth) acrylate, triethylene glycol (meth) acrylate, tetraethylene glycol (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, 1,1,1-trihydroxymethylethane triacrylate, 1,1,1-tris (hydroxymethyl) methylethane triacrylate,
1,1-tris (hydroxymethyl) propane triacrylate and the like can be mentioned.

The proportion (weight ratio) of the monomer used to form the styrene resin and the (meth) acrylate resin is usually 50:50 to 98: 2 [styrene resin: (meth) acrylate) Resin]
It is preferably from 60:40 to 95: 5, and more preferably from 70:30 to 90:10. If the proportion of the monomer used to form the styrene-based resin is less than 50, the nucleus is too small, and the soft focus effect of the cosmetic is undesirably reduced. On the other hand, if the proportion of the styrene-based monomer exceeds 98, the core becomes too large, and the transparency of the cosmetic is liable to be impaired. It is preferable that the nucleus does not contain a hydrocarbon oil or an ultraviolet absorber. If hydrocarbon oils or ultraviolet absorbers are included, when oils elute from the nuclei, the oils accumulate at the interface between the nucleus and the coating layer, exhibiting the effect of particle design due to the difference in refractive index. This is not preferable because it may be difficult to perform.

The average particle diameter of the spherical particles used in the present invention is preferably 0.5 to 100 μm, more preferably 2 to 50 μm. If the average particle diameter is smaller than 0.5 μm, it is difficult to sufficiently exhibit elongation of the particles, and if the average particle diameter is larger than 100 μm, the cosmetic tends to be rough, which is not preferable. Here, the average particle diameter is measured by a Coulter counter. Next, a method for producing spherical particles having a multilayer structure used in the present invention will be described. The spherical particles having a multilayer structure used in the present invention are produced by polymerizing a monomer on the surface of the particles constituting the core to form a coating layer. By appropriately repeating the step of forming the coating layer, a desired number of layers can be formed. Specifically, 100 parts by weight of the particles constituting the nucleus are dispersed in an aqueous medium, and the above-mentioned formulas (II) and (II) are added to the dispersion.
A monomer capable of satisfying I), having a 10-hour half-life temperature of 60 to 80 ° C. and a solubility in water of 0.
By adding a monomer mixture comprising an oil-soluble polymerization initiator of 3 g / 100 ml or less at an addition rate of 5 to 100 parts by weight / 1 hour, the particles constituting the core and the monomer mixture are subjected to suspension polymerization. . By repeating this operation a desired number of times using a desired monomer mixture,
The spherical particles having a multilayer structure used in the present invention can be obtained.

If the 10-hour half-life temperature of the oil-soluble polymerization initiator is lower than 60 ° C. or higher than 80 ° C., it is difficult to control the polymerization reaction, which is not preferable. The solubility of the oil-soluble polymerization initiator in water is 0.3 g / 100.
If it is higher than 0.1 ml, the polymerization is started by the polymerization initiator dissolved in the aqueous medium, and the monomer mixture added later is polymerized by a considerable amount alone to produce minute particles as by-products, and furthermore, the polymerization stability of the system And the spherical particles are likely to aggregate, which is not preferable. The suspension polymerization is carried out by using the particles 100 constituting the core.
In an aqueous medium in which parts by weight are dispersed in an aqueous medium, the formula (II)
The monomer mixture capable of satisfying (III) and (III) is continuously or intermittently added at an addition rate of 5 to 100 parts by weight / 1 hour, preferably 10 to 50 parts by weight / 1 hour. If the rate of addition of the monomer mixture exceeds 100 parts by weight per hour, the monomer mixture is not easily reduced, and it is not preferable because it is easy to polymerize alone. Conversely, if it is slower than 5 parts by weight per hour, it is not preferable in terms of productivity.

The cosmetic of the present invention can be obtained by incorporating the spherical particles having a multilayer structure obtained as described above into the cosmetic. The cosmetics in the present invention include, for example, cosmetics for washing such as soap, body shampoo, facial cleanser, scrub, facial cleanser, toothpaste, etc .; Lotion preparations such as pre-shave lotion, after-shave lotion and body lotion; external preparations for the body such as body powder and baby powder; lotions, creams, milky lotions, packs, hair wash cosmetics, hair dyes, hair styling products, aromatic cosmetics Bath agents, antiperspirants, sunscreen products, suntan products, shaving creams and the like. The content of the spherical particles having a multilayer structure in the cosmetic is not particularly limited and is appropriately adjusted depending on the type of the cosmetic, but is usually about 1 to 60% by weight, and preferably about 3 to 40% by weight.

The cosmetic of the present invention contains 20 to 20 oils having a refractive index of 1.39 to 1.54 per 100 parts by weight of the cosmetic.
You may contain about 0 weight part. When the above-mentioned oil agent is added to the cosmetic of the present invention, a synergistic effect is recognized in terms of transparency and soft focus effect. Refractive index is 1.39
As the oil agent in the range of ~ 1.54, for example, coconut oil,
Fats and oils such as avocado oil, olive oil, palm oil, turtle oil and mink oil; hydrocarbons such as low-boiling hydrocarbons, pristane, petrolatum, squalane, liquid paraffin; lauric acid, myristic acid, stearic acid, oleic acid, and linoleic acid Fatty acids such as acid and linolenic acid; higher alcohols such as lauryl alcohol, myristyl alcohol, cetanol, 2-octyldodecanol and stearyl alcohol; isopropyl myristate, glyceryl-2-monomyristate, glyceryl-1-myristo-
2-oleate, cetyl 2-ethylhexanoate, glyceryl tri-2-ethylhexanoate, glyceryl tricaprylate, oleyl oleate, octyldecyl myristate, octyldodecyl myristate, glyceryl-1-oleate monoester, triester Esters such as diglyceryl isostearate and sorbitan isostearate; and silicone oils such as methylpolysiloxane and methylphenylpolysiloxane. These oil agents can be used alone or in combination of two or more.

Further, within the range not impairing the effects of the present invention,
Components generally used in cosmetics may be appropriately blended according to the purpose. Such components include, for example, water,
Lower alcohols, fats and waxes, hydrocarbons, higher fatty acids, higher alcohols, sterols, fatty acid esters, metal soaps, humectants, surfactants, high molecular compounds, coloring materials, fragrances, preservatives / disinfectants, antioxidants , UV absorber,
Special compounding components are included. Oils and waxes include avocado oil, almond oil, olive oil, cacao butterfat, sesame butter, wheat germ oil, safflower oil, shea butter, turtle oil, camellia oil, persic oil, castor oil, grape oil, macadamia nut oil , Mink oil, egg yolk oil, mokuro, palm oil, rosehip oil, hydrogenated oil, silicone oil,
Orange laffy oil, carnauba wax, candelilla wax, whale wax, jojoba oil, montan wax, beeswax, lanolin and the like.

Examples of the hydrocarbons include liquid paraffin, vaseline, paraffin, ceresin, microcrystalline wax, and squalane. Higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, undecylenic acid,
Oxystearic acid, linoleic acid, lanolin fatty acids, synthetic fatty acids, and the like. As higher alcohols, lauryl alcohol, cetyl alcohol, cetostearyl alcohol, stearyl alcohol, oleyl alcohol, behenyl alcohol, lanolin alcohol, hydrogenated lanolin alcohol, hexyldecanol, octyldecanol, isostearyl alcohol, jojoba alcohol, decyltetradeca Knol and the like.

Sterols include cholesterol, dihydrocholesterol, phytocholesterol and the like. Fatty acid esters include ethyl linoleate, isopropyl myristate, isopropyl lanolin fatty acid, hexyl laurate, myristyl myristate, cetyl myristate, octyl dodecyl myristate, decyl oleate, octyl dodecyl oleate, hexyl decyl dimethyl octanoate, isooctane Cetyl acid,
Decyl palmitate, glyceryl trimyristate, glycerin tri (caprylate / caprate), propylene glycol dioleate, glycerin triisostearate, glyceryl triisooctanoate, cetyl lactate, myristyl lactate, diisostearyl malate, cholesteryl isostearate, 12 And cyclic alcohol fatty acid esters such as cholesteryl hydroxystearate. Examples of the metal soap include zinc laurate, zinc myristate, magnesium myristate, zinc palmitate, zinc stearate, aluminum stearate, calcium stearate, magnesium stearate, and zinc undecylenate.

Examples of the humectant include glycerin, propylene glycol, 1,3-butylene glycol, polyethylene glycol, sodium dl-pyrrolidonecarboxylate, sodium lactate, sorbitol, sodium hyaluronate, polyglycerin, xylitol, maltitol and the like. . As surfactants, higher fatty acid soaps,
Anionic surfactants such as higher alcohol sulfates, N-acyl glutamates and phosphates, cationic surfactants such as amine salts and quaternary ammonium salts, betaine type, amino acid type, imidazoline type, lecithin, etc. And nonionic surfactants such as fatty acid monoglyceride, propylene glycol fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyglycerin fatty acid ester and ethylene oxide condensate.

As the high molecular compound, gum arabic, tragacanth gum, guar gum, locust bean gum, karaya gum, irismos, quince seed, gelatin,
Shellac, rosin, natural polymer compounds such as casein, sodium carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, ethylcellulose,
Semi-synthetic polymer compounds such as sodium alginate, ester gum, nitrocellulose, hydroxypropyl cellulose, crystalline cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, sodium polyacrylate, carboxyvinyl polymer, polyvinyl methyl ether, polyamide resin, silicone oil, nylon particles And synthetic polymer compounds such as resin particles such as polymethyl methacrylate particles, crosslinked polystyrene particles, silicon particles, urethane particles, and polyethylene particles. Coloring materials include iron oxide, ultramarine, konjo, chromium oxide, chromium hydroxide,
Carbon black, manganese violet, titanium oxide, zinc oxide, talc, kaolin, mica, calcium carbonate, magnesium carbonate, mica, aluminum silicate,
Inorganic pigments such as barium silicate, calcium silicate, magnesium silicate, silica, zeolite, barium sulfate, calcined calcium sulfate (baked gypsum), calcium phosphate, hydroxyapatite, ceramic powder, etc., azo-based, nitro-based, nitroso-based, xanthene-based pigments And quinoline, anthraquinoline, indigo, triphenylmethane, phthalocyanine and pyrene tar dyes. In addition, as a powder raw material such as a powder raw material or a coloring material raw material of these high molecular compounds, those subjected to a surface treatment in advance may be used.

As the surface treatment method, known surface treatment techniques can be used, for example, oil treatment with hydrocarbon oil, ester oil, lanolin, etc., dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane, etc. Silicone treatment, perfluoroalkyl group-containing ester, perfluoroalkylsilane,
Fluorine compound treatment with perfluoropolyether and polymer having a perfluoroalkyl group, etc., silane coupling agent treatment with 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, etc., isopropyl triisostearoyl titanate Titanium coupling agent treatment with isopropyltris (dioctyl pyrophosphate) titanate, etc., metal soap treatment, amino acid treatment with acylglutamic acid, etc., lecithin treatment with hydrogenated egg yolk lecithin, etc., collagen treatment, polyethylene treatment, moisturizing treatment, inorganic compound treatment And a treatment method such as mechanochemical treatment. Examples of the flavor include anisaldehyde, benzyl acetate, geraniol and the like.

As the antiseptic / bactericide, methyl parapen,
Ethyl parapen, propyl parapen, benzalkonium, benzethonium and the like can be mentioned. Examples of the antioxidant include dibutylhydroxytoluene, butylhydroxyanisole, propyl gallate, and tocopherol. As the ultraviolet absorber, inorganic absorbers such as fine-particle titanium oxide, fine-particle zinc oxide, fine-particle cerium oxide, fine-particle iron oxide, fine-particle zirconium oxide, benzoic acid,
Organic absorbents such as para-aminobenzoic acid, anthranilic acid, salicylic acid, cinnamic acid, benzophenone, and dibenzoylmethane may be used. As special compounding ingredients, for example, estradiol, estrone, ethinyl estradiol, cortisone, hydrocortisone,
Hormones such as prednisone, vitamins such as vitamin A, vitamin B, vitamin C and vitamin E, citric acid, tartaric acid, lactic acid, aluminum chloride, aluminum potassium potassium sulfate, allantochlorohydroxy aluminum, zinc paraphenol sulfonate, zinc sulfate Skin astringents such as, tincture tincture, pepper tincture, ginger tincture, assembly extract, garlic extract,
Hinokitiol, carpronium chloride, pentadecanoic acid glyceride, vitamin E, estrogen, photoreceptor and other hair growth promoters, magnesium phosphate-L-ascorbate,
And a whitening agent such as kojic acid.

[0024]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. [Synthesis Example 1] [First Step] In a 5 L autoclave equipped with a stirrer, 3000 g of water, 80 g of tribasic calcium phosphate, 1.2 g of sodium dodecyl sulfate, 544 g of styrene, 16 g of divinylbenzene, and 5 g of azobisisobutyronitrile. And the monomer mixture was dispersed with a TK-homomixer manufactured by Tokushu Kika Co., Ltd. to form droplets of about 8 μm. Subsequently, suspension polymerization was carried out under a nitrogen stream at 70 ° C. for 8 hours to obtain resin particles. The average particle size of the resin particles was 7.9 μm. [Second step] 240 g of methyl methacrylate and 3 g of benzoyl peroxide were put into 300 g of water in which 1.2 g of sodium dodecyl sulfate was dissolved, and this monomer mixture was dispersed with an ultrasonic homogenizer to reduce the particle size of the oil droplets. It was about 2 μm. [Third step] The dispersion obtained in the second step was continuously dropped at 70 ° C for 90 minutes into an aqueous dispersion medium in which the resin particles obtained in the first step were dispersed. After the completion of the dropwise addition, polymerization was carried out for 5 hours, then the temperature was raised to 90 ° C., and the reaction was further continued for 3 hours.
Next, the mixture was cooled, hydrochloric acid was added to dissolve the tricalcium phosphate, washed with water, dehydrated, and dried in an oven at 60 ° C. for 1 day to obtain spherical particles having an average particle size of 8.8 μm.
Observation of the spherical particles by a TEM photograph (transmission electron micrograph, magnification: 12,700 times) shown in FIG. 1 revealed that the spherical particles had a two-layer structure composed of a core and a coating layer.
The refractive index of the polymer forming the nucleus was 1.59, and the refractive index of the polymer forming the coating layer was 1.49.

[Synthesis Example 2] [First Step] In a 5 L autoclave equipped with a stirrer, 3000 g of water, 80 g of tribasic calcium phosphate, 1.2 g of sodium dodecyl sulfate, 544 g of styrene, 16 g of divinylbenzene, and 16 g of azobisisobuty 5 g of lonitrile was added, and this monomer mixture was added to T
The mixture was dispersed with a K-homomixer to form droplets of about 8 μm.
Then, suspension polymerization was performed at 70 ° C. for 8 hours under a nitrogen stream to obtain resin particles. The average particle size of the resin particles was 7.5 μm. [Second step] 100 g of styrene, 50 g of methyl methacrylate, 1,6-hexanediol dimethacrylate 1
0 g and 2 g of benzoyl peroxide were put into 200 g of water in which 0.8 g of sodium dodecyl sulfate was dissolved, and this monomer mixture was dispersed with an ultrasonic homogenizer to make the particle diameter of oil droplets about 2 μm. [Third step] The dispersion obtained in the second step was continuously dropped at 70 ° C over 90 minutes into an aqueous dispersion medium in which the resin particles obtained in the first step were dispersed. After completion of the dropwise addition, polymerization was carried out for 5 hours, then the temperature was raised to 90 ° C., and the reaction was further continued for 3 hours to obtain resin particles having an average particle diameter of 8.1 μm.

[Fourth step] 80 g of methyl methacrylate
Then, 2 g of benzoyl peroxide was added to 100 g of water in which 0.4 g of sodium dodecyl sulfate was dissolved, and the monomer mixture was dispersed with an ultrasonic homogenizer to make the particle diameter of oil droplets about 2 μm. [Fifth step] The dispersion obtained in the fourth step was continuously dropped at 70 ° C over 60 minutes into an aqueous dispersion medium in which the resin particles obtained in the third step were dispersed. After the completion of the dropwise addition, polymerization was carried out for 5 hours, then the temperature was raised to 90 ° C., and the reaction was further continued for 3 hours. Then, after cooling, hydrochloric acid is added to dissolve the tricalcium phosphate, followed by washing with water, dehydration, and drying in an oven at 60 ° C. for 1 day to obtain an average particle diameter of 8 consisting of a core, an inner layer and an outer layer. Resin particles having a three-layer structure of 0.3 μm were obtained.
The refractive index of the polymer constituting the core was 1.59, the refractive index of the polymer constituting the inner layer was 1.55, and the refractive index of the polymer constituting the outer layer was 1.49.

Synthesis Example 3 Instead of styrene and divinylbenzene in the first step of Synthesis Example 1, 381 g of methyl methacrylate, 163 g of styrene and 1,6
Except for using 16 g of hexanediol dimethacrylate, resin particles having an average particle size of 8.5 μm were obtained in the same manner as in the first to third steps of Synthesis Example 1. The resin particles have a two-layer structure consisting of a nucleus and a coating layer. The polymer constituting the core has a refractive index of 1.52, and the polymer constituting the coating layer has a refractive index of 1.49. there were. [Production of cosmetics] [Production of powder foundation] [Example 1] Resin particles (Synthesis Example 1) 20 parts by weight Talc 42 parts by weight Sericite 17 parts by weight Titanium oxide 10 parts by weight Red iron oxide 0.6 parts by weight Yellow Iron oxide 1 part by weight Black iron oxide 0.1 part by weight Liquid paraffin 2 parts by weight Octyldecyl myristate 3.5 parts by weight Sorbitan isostearate 0.5 part by weight 2-octyldodecanol 3.0 parts by weight Preservatives appropriate amount perfume appropriate amount Resin particles, talc, sericite, titanium oxide, red iron oxide, yellow iron oxide, black iron oxide were mixed with a Henschel mixer, and liquid paraffin, octyldecyl myristate, sorbitan isostearate, 2-octyldodecanol, A solution obtained by mixing and dissolving the preservative was added and mixed uniformly. After adding a fragrance to this and mixing, it was pulverized and passed through a sieve to obtain a powder. This powder was compression-molded on a metal plate to obtain a powder foundation.

Example 2 A powder foundation was obtained in the same manner as in Example 1, except that the resin particles were changed to those obtained in Synthesis Example 2. [Example 3] Resin particles (Synthesis Example 1) 20 parts by weight Talc 47 parts by weight Sericite 17 parts by weight Titanium oxide 10 parts by weight Red iron oxide 0.6 parts by weight Yellow iron oxide 1 part by weight Black iron oxide 0.1 part by weight Part Octyldecyl myristate 3.5 parts by weight Sorbitan isostearate 0.5 parts by weight Preservatives appropriate amount perfume appropriate amount Resin particles, talc, sericite, titanium oxide, red iron oxide, yellow iron oxide, black iron oxide mixed with Henschel mixer Then, a mixture obtained by mixing and dissolving octyldecyl myristate, sorbitan isostearate, and a preservative was added thereto and uniformly mixed. After adding the fragrance and mixing,
Crushed and passed through a sieve. This was compression-molded on a metal plate to obtain a powder foundation.

Comparative Example 1 A powder foundation was obtained in the same manner as in Example 1 except that the resin particles were changed to those obtained in Synthesis Example 3. Comparative Example 2 A powder foundation was obtained in the same manner as in Example 1 except that the resin particles were replaced with crosslinked polystyrene particles (average particle size: 8.8 μm). A sensory test was conducted on the cosmetics thus manufactured by 10 panelists. The evaluation items in this test were elongation, soft focus effect, and transparency, and each item was evaluated on a 5-point scale based on the following criteria. 1 ... bad 2 ... somewhat bad 3 ... normal 4 ... somewhat good 5 ... good The results of this sensory test are shown in Table 1. In addition, the numerical value in a table | surface showed the average value of evaluation of ten panelists.

[0030]

[Table 1]

As described above, a cosmetic containing a spherical particle having a multilayer structure in which each layer is formed of a polymer having a specific average particle diameter and a different refractive index has a single effect in addition to elongation and soft focus effect. It was found that particles, such as cross-linked polystyrene, had transparency that could not be obtained when blended into cosmetics.

[0032]

The spherical particles having a specific average particle diameter and a multilayer structure in which the polymers constituting each layer have different refractive indices have a single particle (crosslinked polystyrene) in addition to the elongation and soft focus effect. , A transparent feeling that could not be obtained when blended. In particular, the refractive index is 1.
When used in combination with an oil agent in the range of 39 to 1.54, a synergistic effect of a soft focus effect and transparency is recognized.

[Brief description of the drawings]

FIG. 1 is a TEM photograph of the resin particles obtained in Synthesis Example 1.

Claims (6)

[Claims] 1. The average particle diameter (μm) is D, the refractive index of the polymer constituting each layer is _nk [the refractive index of the polymer constituting the outermost layer is n _1, and the refractive index of the polymer constituting the other layers is The refractive index is set to n ₂ , n ₃ ,.
··· _nk (k is an integer of 2 to 10)], the formula: 0.5 ≦ D ≦ 100 (I) 1.3 ≦ _nk ≦ 1.7 (II) │n ₂ A cosmetic, comprising spherical particles having a multilayer structure that satisfies -n ₁ | ≧ 0.05 (III). 2. The refractive index of a polymer constituting each layer is represented by n _k
[The refractive index of the polymer constituting the outermost layer is n _1, and the refractive indices of the polymers constituting the other layers are n ₂ , n ₃ ,... _Nk (k is 2 -10
When the of an integer) to], _{wherein: n 2 -n 1 ≧ 0.05 (} IV) n x -n x-1> 0 and (V) (x is an integer of 3～K) The cosmetic according to claim 1, which is satisfied. 3. The refractive index of a polymer constituting each layer is n _k
[The refractive index of the polymer constituting the outermost layer is n _1, and the refractive indices of the polymers constituting the other layers are n ₂ , n ₃ ,... _Nk (k is 2 -10
When the a is) to] integer, wherein: n _x -n _x-1 <claim 1 satisfying _{n x-1 -n x-2} (VI) (x is an integer of 3～K) Or 2
The cosmetic according to any one of the above. 4. The cosmetic according to claim 1, wherein the spherical particles have a two-layer structure, the nucleus is formed of a styrene resin, and the coating layer is formed of a (meth) acrylate resin. . 5. A dispersion in which 100 parts by weight of spherical particles constituting cores are dispersed in an aqueous medium, a monomer and a 10-hour half-life temperature of 60 to 80 ° C., and solubility in water. The monomer mixture consisting of an oil-soluble polymerization initiator having a
The cosmetic according to any one of claims 1 to 4, wherein a coating layer is formed on particles constituting the nucleus by adding the suspension at a rate of 100 parts by weight per hour for suspension polymerization. 6. The cosmetic according to claim 1, wherein the cosmetic contains 20 to 200 parts by weight of an oil agent having a refractive index of 1.39 to 1.54 based on 100 parts by weight of the spherical particles. .