JP4657753B2 - Two-layer separated cosmetic - Google Patents

Description

  The present invention relates to a two-layer separated cosmetic containing a crosslinked resin powder having specific rubber elasticity.

  Cosmetics containing powder include makeup cosmetics such as foundation, white powder, blusher, eye shadow, body cosmetics such as body powder, baby powder, body lotion, face lotion, pre-shave lotion, etc. Lotion preparations are commercially available. In these body cosmetics and lotion preparations, the powder is used for the purpose of imparting functions such as improvement on skin, improvement in touch, and hiding effect. Examples thereof include inorganic powders such as silica and talc, and resin powders composed of polymethyl methacrylate, crosslinked polystyrene, nylon, polyethylene, and the like. However, these powder materials have characteristics corresponding to their types, but are insufficient in that they provide a soft feel and a smooth feel.

Patent Documents 1 to 3 disclose external preparations containing crosslinked (meth) acrylate resin particles having a compressive strength of 0.05 to 0.6 kgf / mm ² . Such particles have good elongation and feel, but are not yet satisfactory, and there is a need for particles that have even better feel such as elongation, smoothness, and soft feeling.
JP 2000-186017 A JP 2000-302624 A JP 2002-265529 A

  Two-layer separated cosmetics such as pre-shave lotion, face lotion, body lotion and the like in which inorganic powder such as silica and talc and resin powder are blended in a low-viscosity liquid have been commercialized. When such cosmetics are applied to the skin, the powder reduces the stickiness of sweat and sebum and improves the smoothness of the shaver and smoothness of the skin. I can't get a feel. Particularly in a dry environment, the skin feels like a powder, and the skin feel after applying to the skin after shaving is not preferable.

  Therefore, the problem of the present invention is that the two-layer separation type that can provide a smooth feel without being sticky while maintaining non-stickiness on the skin, and is excellent in the sustainability of the smoothness and non-stickiness of the skin. To provide cosmetics.

The present invention provides a two-layer separated cosmetic containing a crosslinked (meth) acrylate resin powder having a compressive strength of 0.7 to 10 kgf / mm ² and a liquid medium.

  The two-layer separated cosmetic of the present invention can give a smooth feel without being sticky while ensuring the non-stickiness of the skin, and is also excellent in the sustainability of the smoothness and non-stickiness of the skin. .

  In the present invention, the two-layer separated cosmetic refers to a cosmetic in which powder is blended in a liquid medium selected from water, lower alcohol, polyhydric alcohol and the like. When such a cosmetic is left standing, the powder settles and separates into two layers, a liquid layer and a powder layer. However, when shaken during use, the powder is easily dispersed into a suspension. The user can apply it to the skin in that state.

  Hereinafter, the components constituting the two-layer separated cosmetic of the present invention will be sequentially described.

[Crosslinked (meth) acrylic ester resin powder]
The crosslinked (meth) acrylic acid ester resin powder used in the present invention has a compressive strength of 0.7 to 10 kgf / mm ² , particularly ² to 8 kgf / mm ² from the viewpoint of obtaining non-sticky and smooth skin. mm ² is preferred.

  Here, the compression strength is the following formula based on the load and particle diameter when the resin particle is subjected to a compression test with a microcompression tester MCT-M200 manufactured by Shimadzu Corporation. Is a value calculated by. The compressive strength is measured at 25 ° C.

Compressive strength (kgf / mm ² ) = 2.8 × load (kgf) / {π × particle diameter (mm) × particle diameter (mm)}
The compressive strength of the resin particles can be adjusted as appropriate by controlling the types and blending amounts of the monomer and the crosslinking agent constituting the resin particles.

The crosslinked (meth) acrylic acid ester resin powder used in the present invention includes at least one monomer selected from acrylic acid ester and methacrylic acid ester (hereinafter referred to as (meth) acrylic acid ester monomer) and Cross-linked (meth) acrylic ester resin powder obtained by copolymerizing a monomer component containing a monomer having a carboxyl group is preferable.
In the present specification, “(meth) acryl” is a concept including both acrylic and methacrylic.

  The (meth) acrylic acid ester monomer used in the present invention is preferably a (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl group. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate , Stearyl (meth) acrylate and the like. Among these, alkyl (meth) acrylates having 4 to 18 carbon atoms in the alkyl group such as butyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate are particularly preferable. You may use these in combination of multiple types. The proportion of the (meth) acrylic acid ester monomer in all monomer components (including a crosslinkable monomer described later) is preferably 30 to 98% by mass, more preferably 50 to 85% by mass. .

  Examples of the monomer having a carboxyl group used in the present invention include (meth) acrylic acid, maleic acid, fumaric acid, crotonic acid, and itaconic acid. You may use these in combination of multiple types. The ratio of the monomer having a carboxyl group in all the monomer components is 0.1 to 30 from the viewpoint of suppressing powder coalescence and obtaining a good powder feel (smoothness, smooth feeling). % By mass is preferable, and 1 to 10% by mass is more preferable.

  A part of the carboxyl groups contained in the crosslinked (meth) acrylic acid ester resin powder may be neutralized. The base for neutralization is preferably an inorganic base such as sodium hydroxide, potassium hydroxide or ammonia, but organic bases such as amines, alkanolamines and basic amino acids can also be used. From the viewpoint of further improving the smoothness and smoothness of the powder, the degree of neutralization is preferably 1 to 30%, particularly preferably 1 to 20%. Here, the degree of neutralization represents the ratio of the number of moles of the added base to the number of moles of the carboxyl group of the monomer having a carboxyl group, expressed as a percentage.

  The monomer component preferably contains a crosslinkable monomer having two or more vinyl groups as a crosslinking agent. Examples of such crosslinkable monomers include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, decaethylene glycol di (meth) acrylate, pentadecaethylene glycol di ( (Meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, (meth) Allyl acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, diethylene glycol di (meth) acrylate phthalate, caprolactone-modified dipentaerythritol hexa (meth) Acrylate, caprolactone-modified hydroxypivalate ester neopentyl glycol di (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate and other (meth) acrylate crosslinkable monomers, divinylbenzene, divinylnaphthalene and these And aromatic divinyl monomers such as derivatives thereof. These may be used alone or in combination of two or more. Among these crosslinkable monomers, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4- (Poly) alkylene glycol di (meth) acrylate such as butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, caprolactone-modified hydroxypivalate ester neo Since pentyl glycol di (meth) acrylate and polyester (meth) acrylate have low skin irritation, they are particularly suitable for use as a two-layer separated cosmetic. These crosslinkable monomers are preferably used in an amount of 3 to 50% by mass relative to the total monomer components.

  As a monomer component, in addition to the above (meth) acrylic acid ester monomer, a monomer having a carboxyl group and a crosslinkable monomer, other monomers copolymerizable with these may be copolymerized. Good. Examples of other monomers include styrene, (meth) acrylonitrile, (meth) acrylamide, vinyl acetate, vinyl pyrrolidone and the like.

  Crosslinked (meth) acrylic acid ester resin powder is, for example, a monomer component containing the above (meth) acrylic acid ester monomer, a monomer having a carboxyl group and a crosslinkable monomer, It can be obtained by polymerization by aqueous suspension polymerization, emulsion polymerization, seed polymerization, dispersion polymerization or the like using a polymerization initiator or the like. Of these, the aqueous suspension polymerization method is preferred from the viewpoint that it is easy to obtain spherical and uniform resin powder.

  Aqueous suspension polymerization is performed by mixing an oil phase containing a monomer and an aqueous phase, and then raising the temperature while stirring. At this time, a surfactant is used as a dispersant. The amount of the surfactant used is preferably 0.01 to 50 parts by mass, more preferably 0.01 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of all monomer components. preferable.

  Here, as the surfactant, those having a sulfonic acid (salt) group are preferable. Thereby, it is possible to obtain a more smooth and smooth resin powder.

  Examples of the surfactant having a sulfonic acid (salt) group include those described in paragraph Nos. 0032 to 0036 of JP-A No. 2003-146826. Among them, an alkyl or alkenyl ether sulfonic acid or a salt thereof, which has an alkyl group or alkenyl group having 5 to 30 carbon atoms and may have an average of 0.5 to 25 moles of alkylene oxide added in one molecule, and carbon An acylated taurine having an alkyl group or an alkenyl group of 5 to 30 or a salt thereof is preferred, and an acylated taurine (salt) represented by the following general formula (I) is particularly preferred.

R ¹ CONR ² CH ₂ CH ₂ SO ₃ M (I)
[Wherein, R ¹ represents an optionally substituted alkyl group or alkenyl group having 5 to 30 carbon atoms, R ² represents a hydrogen atom or a methyl group, and M represents a hydrogen atom or a cation. ]
In general formula (I), as R < ¹ >, a C6-C24 alkyl group or alkenyl group is preferable. Specific examples include hexyl, octyl, nonyl, decyl, undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, docosyl, tetracosyl, decenyl, dodecenyl, tetradecenyl, hexadecenyl, octadecenyl, eicosenyl and the like. Examples of the substituent for the alkyl group or alkenyl group include a hydroxyl group, a carboxyl group, an ester group, an ether group, and an amide group.

  Examples of the cation represented by M include cations such as alkali metal, ammonium, alkyl or alkenylamine having 1 to 22 carbon atoms, alkanolamine having 1 to 22 carbon atoms, basic amino acid salt, lithium, sodium, Alkali metal ions such as potassium are preferred, and sodium ions are particularly preferred.

Examples of the polymerization initiator used for polymerization include benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxydicarbonate, cumene hydroperoxide, t-butyl hydroperoxide and the like. And oil-soluble azo compounds such as 2,2′-azobisisobutyronitrile and 2,2′-azobis (2,4-dimethylvaleronitrile). The addition amount of the polymerization initiator is preferably 0.1 to 10% by mass with respect to all monomer components.
The polymerization temperature and the polymerization time are not particularly limited, but the polymerization temperature is preferably 40 to 100 ° C. and the polymerization time is preferably 1 to 15 hours.

  The shape of the resin powder of the present invention is preferably a spherical body because it feels good on the skin. The average particle size is preferably 1 μm or more, more preferably 1.5 μm or more, and particularly preferably 2 μm or more from the viewpoint of reducing squeakiness. On the other hand, from the viewpoint of suppressing roughness and further improving the skin fixing property, it is preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably 6 μm or less.

  The average particle size was measured using a laser diffraction type particle size distribution measuring device (for example, LA-920 manufactured by Horiba, Ltd.), and the weight average particle size of a water suspension of powder at 20 ° C. with a relative refractive index of 1.1. It can be determined by measuring the diameter.

[Liquid medium]
Examples of the liquid medium used in the present invention include at least one selected from water, lower alcohols and polyhydric alcohols, and a mixed solvent of water and lower alcohols and / or polyhydric alcohols is preferable. The mixing ratio of water and alcohols is mass ratio, and water / alcohols = 1/99 to 99/1 is preferable, and 5/95 to 95/5 is more preferable.

  Examples of the lower alcohol used in the present invention include alcohols having 1 to 4 carbon atoms such as methanol, ethanol, isopropyl alcohol, and ethanol is particularly preferable. Examples of the polyhydric alcohol include propylene glycol, 1,3-butylene glycol and glycerin.

  In the two-layer separated cosmetic of the present invention, by changing the composition of the liquid medium, for example, the ratio of water and alcohols, it is possible to adjust the drying speed, skin feel, etc. according to the target product characteristics. is there. Also, by increasing the blending amount of alcohols, it becomes possible to uniformly dissolve a large amount of active ingredients such as oils such as ester oils, anti-inflammatory agents, UV absorbers, plant extracts, etc. Can be granted.

[Double-layered cosmetic]
The two-layer separated cosmetic of the present invention is a shaving lotion such as a pre-shave lotion or after-shave lotion, a face lotion or body lotion that gives a dry feel to skin that is sticky with sweat or sebum, a deodorant agent, It is preferably used as a lotion or the like that is applied to the foot to facilitate the removal of gloves and stockings.

The two-layer separated cosmetic of the present invention is characterized by containing the above-mentioned crosslinked (meth) acrylic ester resin powder. The content of the crosslinked (meth) acrylic ester resin powder in the two-layer separated cosmetic of the present invention is 0.5% from the viewpoint of suppressing the stickiness of the skin, imparting smoothness, and preventing whitening of the skin. -50 mass% is preferable, 1-30 mass% is still more preferable, and 1-15 mass% is especially preferable.
In addition, the content of the liquid medium in the two-layer separated cosmetic of the present invention is preferably 50 to 99.5% by mass, more preferably 70 to 99% by mass, and particularly preferably 80 to 98% by mass.

  In the two-layer separated cosmetic of the present invention, other powders, for example, inorganic powders such as talc and titanium can be appropriately mixed within a range not impairing the caking resistance and stability. Further, the two-layer separated cosmetic of the present invention further includes a surfactant, an oil agent, a refreshing agent, a flame retardant, a medicinal agent, a moisturizer, a bactericide, an antiperspirant, and an antioxidant generally used in cosmetics. , Whitening agents, ultraviolet absorbers, fragrances, colorants, and the like can be appropriately mixed as long as the effects of the present invention are not impaired.

  The two-layer separated cosmetic of the present invention can be obtained by mixing the crosslinked (meth) acrylic ester resin powder and liquid medium, and other components as necessary, by ordinary means. Filled into a container and commercialized. Examples of the container include a liquid cosmetic bottle, a roll-on container, a pump spray container, and an aerosol container.

  The two-layer separated cosmetic of the present invention can suppress the stickiness and roughness of the skin, improve the shaver's slipping and the smoothness of the skin, and can maintain these feelings.

  Unless otherwise specified,% in the examples is% by mass.

Production Example 1
In a beaker, 85 g of lauryl methacrylate, 15 g of ethylene glycol dimethacrylate, and 2 g of lauroyl peroxide were charged, mixed and stirred to dissolve. Here N- stearoyl -N- methyl taurate sodium (SMT) was added to ion-exchanged water 400g obtained by 0.75g dissolved, the particle size with a homomixer was dispersed until the 2.4 [mu] m.

  The dispersion was poured into a four-necked flask and purged with nitrogen for 30 minutes while stirring. The temperature inside the flask was heated to 80 ° C. with an oil bath. After reaching 80 ° C., polymerization was performed for 5 hours, and then cooled to room temperature. The dispersion liquid of the polymerized particles was lyophilized and the particles were collected to obtain a resin powder A.

Production Example 2
A beaker was charged with 82 g of lauryl methacrylate, 3 g of methacrylic acid, 15 g of ethylene glycol dimethacrylate, and 2 g of lauroyl peroxide, and dissolved by stirring. To this, 400 g of ion-exchanged water in which 0.75 g of sodium dodecyl sulfate (SDS) was dissolved was added and dispersed with a homomixer until the particle size became 2.5 μm.

  The dispersion was poured into a four-necked flask and purged with nitrogen for 30 minutes while stirring. The temperature inside the flask was heated to 80 ° C. with an oil bath. After reaching 80 ° C., polymerization was performed for 5 hours, and then cooled to room temperature. The dispersion liquid of the polymerized particles was lyophilized and the particles were collected to obtain a resin powder B.

Production Example 3
A beaker was charged with 82 g of lauryl methacrylate, 3 g of methacrylic acid, 15 g of ethylene glycol dimethacrylate, and 2 g of lauroyl peroxide, and dissolved by stirring. 400 g of ion-exchanged water in which 0.75 g of sodium N-stearoyl-N-methyltaurine (SMT) was dissolved was added thereto and dispersed with a homomixer until the particle size became 2.2 μm.

  The dispersion was poured into a four-necked flask and purged with nitrogen for 30 minutes while stirring. The temperature inside the flask was heated to 80 ° C. with an oil bath. After reaching 80 ° C., polymerization was performed for 5 hours, and then cooled to room temperature. The dispersion liquid of the polymerized particles was lyophilized and the particles were collected to obtain resin powder C.

Production Example 4
In Production Example 3, a neutralized product of Resin Powder C was obtained in the same manner as in Production Example 3 except that 3.9 g of 1N NaOH was added dropwise to the dispersion of polymerized particles for neutralization. The neutralized product of the resin powder C had a carboxyl group neutralization degree of 11.2%.

  When the compressive strength and average particle size of the resin powders A, B, C, and C obtained in Production Examples 1 to 4 were measured by the following methods, the results shown in Table 1 were obtained.

<Compressive strength measurement method>
The resin particle is subjected to a compression test up to a load of 1 gf at a constant load speed of 29 mgf / s using a micro compression tester MCT-M200 manufactured by Shimadzu Corporation. From the following formula. Ten samples were measured, and the average value was taken as the compressive strength.

Compressive strength (kgf / mm ² ) = 2.8 × load (kgf) / {π × particle diameter (mm) × particle diameter (mm)}.

<Average particle size measurement method>
Using a Horiba, Ltd. laser diffraction scattering particle size distribution analyzer (model number: LA920), the relative refractive index is 1.10 (the refractive index of the resin powder is 1.46, the refractive index of water is 1). .33), the median diameter when the particle diameter was measured was defined as the average particle diameter.

Examples 1-4 and Comparative Examples 1-2
Two-layer separated lotions having the compositions shown in Table 2 were prepared. Five professional panelists applied this to the forearm and scored the following evaluation items for the feeling of use. The average score of 5 people was ranked according to the following criteria. The results are shown in Table 2.

<Evaluation items>
・ Slip on the skin Score 4… Slide well Score 3… Slide slightly Score 2… Not slip very much Score 1… Do not slip ・ Slightly loose Score 4… Do not touch Score 3… Do not touch too much Score 2… Slightly touch Score 1… Smoothness / Durability of skin slip (1 hour after application)
Score 4 ... Skin slipping lasts. Score 3 ... Skin slipping lasts a little. Score 2 ... Skin slipping doesn't last much. Score 1 ... Skin slipping doesn't last.
Average score 3.5-4.0 ... ◎
Average score 2.5-3.4 ... ○
Average score 1.5-2.4 ... △
Average score 1.0-1.4 ... ×

* 1: Methylsiloxane network polymer powder (manufactured by Shin-Etsu Chemical Co., Ltd., compressive strength 12 kgf / mm ² , average particle size 2 μm).

Example 5
A two-layer separated lotion having the following composition was prepared. The obtained lotion had good skin slip and was not bulky, and the skin slip was maintained even after 1 hour of application.

<Composition>
Resin powder C 1.00%
Ethanol 7.00
Glycerin 1.00
Oat extract 0.50
1,3-butylene glycol 0.20
Citric acid 0.10
Sodium citrate 0.10
Methyl paraoxybenzoate 0.10
Fragrance 0.01
Polyethylene glycol monolaurate ^{* 1} 0.01
Purified water 89.98
Total 100.00
* 1: Emanon 1112 (manufactured by Kao Corporation).

Example 6
A two-layer separation type pump spray lotion having the following composition was prepared. The obtained lotion had good skin slip and was not bulky, and the skin slip was maintained even after 1 hour of application.

<Composition>
Resin powder B 2.000%
Polyoxyethylene isocetyl ether (20EO) 0.500
Zinc paraphenol sulfonate 0.010
Glycerin 0.500
Polyethylene glycol 1540 ^{* 1} 1.000
Highly polymerized polyethylene glycol ^{* 2} 0.001
l-Menthol 0.010
Edetate disodium 0.010
Methyl paraoxybenzoate 0.100
Ethanol 5.000
Purified water 90.869
Total 100.000
* 1: PEG-1540 (manufactured by Sanyo Chemical Industries)
* 2: Alcox E-100 (manufactured by Meisei Chemical Co., Ltd.).

Example 7
A two-layer separation type pre-shave lotion having the following composition was prepared. The obtained pre-shave lotion had good slippage when shaved with an electric shaver, was not bulky, and had a good skin feel after shaving.

<Composition>
Neutralized product of resin powder C 5.0%
Neopentyl glycol dicaprate 1.0
Isostearyl glyceryl ether 0.5
1,3-butylene glycol 0.1
β-glycyrrhetinic acid 0.1
Fragrance 0.3
Ethanol 81.0
Purified water 12.0
Total 100.0

Claims (3)

A two-layer separated cosmetic containing a crosslinked (meth) acrylate resin powder having a compressive strength of 0.7 to 10 kgf / mm ² and a liquid medium ,
The crosslinked (meth) acrylic acid ester resin powder is obtained by copolymerizing a monomer component containing at least one monomer selected from acrylic acid ester and methacrylic acid ester and a monomer having a carboxyl group. A two-layer separated cosmetic . Two-layer separation type cosmetic composition of claim 1, wherein the degree of neutralization of the carboxyl groups in the resin powder is 1 to 30%. The two-layer separated cosmetic according to claim 1 or 2 , wherein the resin powder has an average particle diameter of 1 to 10 µm.