JP6672730B2 - Cosmetic comprising nanoemulsion and method for producing the same - Google Patents

Description

The present invention relates to a process for the production of cosmetic and this cosmetic consisting of nano emulsion of nano-level particle size.

Among external preparations such as cosmetics and pharmaceuticals that maintain a high skin barrier function, the role of intercellular lipid ceramide in the barrier function has been confirmed. However, ceramides are generally characterized by a high melting point, high crystallinity, and low compatibility with other compounds. It was difficult to obtain a sufficiently developed external preparation.
Therefore, instead of ceramides, a polymer of a monomer raw material containing a monomer similar to the chemical structure of ceramide, which can be easily blended with other cosmetic materials, is used as an external preparation.

  Among them, Patent Literature 1 describes a nanosphere using a copolymer of a glycerol (meth) acrylate monomer and a monomer having a long-chain alkyl group, and this polymer nanosphere has an effective lipophilic property. It is described that an emollient effect or the like can be imparted by including a component. However, the lipophilic active ingredient that can be included is very small, and there is room for further improvement.

  Patent Document 2 discloses an emulsified cosmetic for skin containing a glyceryl amide methacrylate / stearyl methacrylate copolymer, a nonionic surfactant, a derivative of fatty acid and glycerin, and the like. . However, the present invention does not form nanospheres, and therefore has room for improvement in feel.

Patent Document 3 describes an emulsified cosmetic for skin containing a glycerylamidoethyl methacrylate / stearyl methacrylate copolymer, a silicone-based surfactant, a polyhydric alcohol, and the like. However, even in the present invention, no nanosphere was formed, and therefore, there was still room for improvement in the feel.
As described above, by including the oily component in the polymer nanosphere, the feeling of use and stability of the encapsulated substance can be improved. However, in the prior art, the amount of the oily component that can be included in the polymer nanosphere was very small.

JP 2007-119374 A JP 2009-149622 A JP 2009-149624 A

As described above, an object of the present invention, the polymer nanospheres can increase the amount of oily component to be encapsulated to provide a cosmetic and method of manufacturing the cosmetic consisting of containing Muna Bruno emulsion.

The present inventors have made intensive studies in view of the above matters, a copolymer having a specific structure similar to ceramides, non-ionic surfactant having a specific HLB value, the three components of the polyhydric alcohol specific It has been found that a bicontinuous microemulsion can be formed by emulsifying a composition for emulsifying a nanoemulsion and an oil component as the component (E) in a combined ratio.
Further, the present inventors have found that a nanoemulsion obtained by diluting this bicontinuous microemulsion with water can have a large amount of an (E) oily component in the polymer nanosphere, and thus has excellent stability. Was completed.
That is, the present invention provides the following [1] and [2] .

（式中、Ｒ^１は水素原子またはメチル基を表し、Ｒ^２は−（ＣＨ_２）ｎ−を表し、ｎは１〜４の整数である。）

（式中、Ｒ^３は水素原子またはメチル基を表し、Ｒ^４は炭素数１２〜２４の炭化水素基を表す。）
（Ｂ）成分：ＨＬＢ値が１０〜１６である非イオン性界面活性剤
（Ｃ）成分：多価アルコール
（Ｄ）成分：水 [1] A composition for nanoemulsion emulsification comprising the following components (A) to (D), wherein the mass ratio of each component satisfies the following conditions, and an oil component as the component (E) is emulsified. A cosmetic comprising a nanoemulsion obtained by diluting a bicontinuous microemulsion with water .
(A) / (B) = 0.1-0.7
(C) / [(A) + (B)] = 3 to 8
(D) / [(A) + (B)] = 0.2 to 1.2
Component (A): Consists of a structural unit (a1) represented by the following formula (1) and a structural unit (a2) represented by the formula (2), and the molar ratio of the structural unit (a1) :( a2) is 40. : A copolymer having a weight average molecular weight of 5,000 to 5,000,000, which is 60 to 80:20.

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents — (CH ₂ ) n—, and n is an integer of 1 to 4.)

(In the formula, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a hydrocarbon group having 12 to 24 carbon atoms.)
(B) Component: Nonionic surfactant having an HLB value of 10 to 16 (C) Component: Polyhydric alcohol (D) Component: Water

[ 2 ] A method for producing the cosmetic according to the above [ 1 ], comprising the following step (I) and step (II).
Step (I): (A) component, (B) component, (C) component, (D) component and (E) a Ingredient mixing, process step of preparing a bicontinuous microemulsion (II): step (I Step of diluting the bicontinuous microemulsion obtained in the above) with water to form a nanoemulsion

According to the composition for nanoemulsion emulsification used for emulsification in the production method of the present invention, it is possible to prepare an oil-in-water emulsion containing a polymer nanosphere capable of increasing the amount of an encapsulated oily component. .
Further, the cosmetic of the present invention, since a nano-emulsion obtained by a bicontinuous microemulsion obtained by emulsifying the above nanoemulsion emulsified composition and an oily component was diluted with water, the polymer nano in the prior art Compared to a cosmetic containing Fear, it has a higher stability, so that the skin care effect and the hair care effect of the oily component can be more enhanced.
Further, according to the production method of the present invention, the cosmetic of the present invention can be easily produced.

  Hereinafter, embodiments of the present invention will be described.

(Nanoemulsion composition for emulsification)
The composition for emulsifying a nanoemulsion of the present invention comprises a copolymer (A) as a component (A), a nonionic surfactant (B) as a component (B), a polyhydric alcohol (C) as a component (C), and It is composed of water (D) as the component (D). In the following, component (A) is a copolymer (A), component (B) is a nonionic surfactant (B), component (C) is a polyhydric alcohol (C), and component (D) is water ( D). Hereinafter, each component will be described.

<Copolymer (A)>
The copolymer (A) used in the present invention comprises a structural unit (a1) represented by the formula (1) and a structural unit (a2) represented by the formula (2).
The structural unit (a1) and the structural unit (a2) are respectively a glycerol (meth) acrylate monomer (hereinafter abbreviated as a GU monomer) represented by the following formula (1 ′) and a formula (2 ′) )) (Hereinafter abbreviated as LH monomer). The polymerization of the GU monomer and the LH monomer can be performed by a known method as described later.

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents — (CH ₂ ) n—, and n is an integer of 1 to 4.)

  Examples of the GU monomer include glycerol-1-methacryloyloxyethyl urethane, glycerol-1-methacryloyloxypropyl urethane, and the like, and glycerol-1-methacryloyloxyethyl urethane is preferable from the viewpoint of ease of synthesis. As the GU monomer, one of these can be used alone, or two or more can be used as a mixture.

(In the formula, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a hydrocarbon group having 12 to 24 carbon atoms.)

LH monomer ^{R 4} is 12 to 24 carbon atoms, preferably 14 to 20, particularly preferably 16 to 18 hydrocarbon group. If the carbon number of the hydrocarbon group is too small, the water solubility of the copolymer will increase, and it may be difficult to form a polymer nanosphere without self-association in water. If the carbon number is too large, the polymer nanosphere may not be stabilized because the particle diameter of the polymer nanosphere becomes large.
The hydrocarbon group may be a saturated or unsaturated hydrocarbon group, or may be a linear or branched hydrocarbon group.

  Examples of the LH monomer include linear or branched alkyl (meth) acrylates such as dodecyl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate, and docosanyl (meth) acrylate. Is raised. As the LH monomer, one of these can be used alone or two or more of them can be used in combination.

The weight average molecular weight of the copolymer (A) is in the range of 5,000 to 5,000,000, and preferably in the range of 10,000 to 1,000,000. If the weight average molecular weight of the copolymer is too small, the stability of the polymer nanosphere may decrease, and if the weight average molecular weight is too large, it may be difficult to form the polymer nanosphere.
In the present invention, the weight average molecular weight of the copolymer (A) is a weight-based average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

  The molar ratio of the structural units (a1) :( a2) in the copolymer (A) is from 40:60 to 80:20, and the molar ratio is the structural molar ratio of the GU monomer to the LH monomer. The same is true for That is, the constituent molar ratio of the GU monomer to the LH monomer is 40 to 80 mol% of the GU monomer and 60 to 20 mol%, and preferably 50 to 70 mol% of the GU monomer. And 50 to 30 mol% of LH monomer. When the proportion of the LH monomer is too small, it may be difficult to sufficiently provide the stability of the polymer nanosphere dispersion, and when the proportion of the LH monomer is too large, the copolymer may form as a polymer nanosphere. May be difficult to form.

In order to produce the copolymer (A), the monomer raw material containing the GU monomer may be directly polymerized in a bulk state, or a solution may be added and a solution polymerization may be performed. Alternatively, dispersion polymerization in a dispersed state can be performed.
As the solvent used in the solution polymerization or the dispersion polymerization, any solvent can be used, for example, methanol, ethanol, isopropanol, n-propanol, butanol, dimethylformamide, dimethylsulfoxide, dimethylacetamide, acetonitrile, acetic acid Ethyl, a mixture of water and at least one of these organic solvents, and other various solvents are mentioned.

The polymerization of the monomer raw material containing the GU monomer can be performed by radical polymerization.
The radical polymerization can be performed using a radical initiator. Examples of the radical initiator include organic peroxides such as benzoyl peroxide, t-butylperoxy neodecanoate, and succinic peroxide; 2,2′-azobisisobutyronitrile, and 2,2 ′ Azo compounds such as dimethyl azobisisobutyrate. From the viewpoints of polymerization characteristics, availability, easy removal in purification, and the like, 2,2′-azobisisobutyronitrile is preferred.
The amount of the radical initiator to be used is generally preferably 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the monomer raw material. The polymerization temperature and the polymerization time can be appropriately selected and determined depending on the type of the radical initiator, the presence or absence of the other monomer, and the type. For example, when radically polymerizing a monomer material containing a GU monomer, dimethyl 2,2′-azobisisobutyrate is used as a radical initiator, the polymerization temperature is preferably 50 to 70 ° C., and the polymerization time is 8 minutes. About 48 hours is appropriate.
The copolymer (A) obtained by radical polymerization is purified and dried by a known method such as reprecipitation method, membrane separation method, solvent extraction method, supercritical extraction method, extractive distillation method, freeze drying, spray drying and the like. The amount of impurities such as residual monomers and organic solvents is preferably 5000 ppm or less, more preferably 500 ppm or less.

<Nonionic surfactant (B)>
The nonionic surfactant (B) used in the present invention has an HLB (hydrophile-lipophile balance) value of 10 to 16, preferably 12 to 15. If the HLB value is too small or too large, it is difficult to make a bicontinuous microemulsion, and it may be difficult to form an oil-in-water emulsion having a nano-level particle size.
The nonionic surfactant (B) used in the present invention is not limited to a nonionic surfactant as long as the HLB value is in the range of 10 to 16. Fatty acid ester type nonionic surfactants such as alcohol fatty acid ester, polyethylene glycol fatty acid ester, polyglycerin fatty acid ester and polyoxyethylene cured castor; alkyl or aryl ether type such as polyoxyethylene alkyl ether and polyoxyethylene alkyl phenyl ether Nonionic surfactant; polyoxyethylene-polyoxypropylene block copolymer; polyoxyethylene-polyoxypropylene block copolymer adduct of ethylenediamine; polyoxyethylene alkylamine, and the like.

Here, the HLB value can be obtained by the Griffin method represented by the following equation.
HLB value = 20 × (molecular weight of hydrophilic group / total molecular weight)

  Examples of the nonionic surfactant (B) suitable for satisfying the above HLB include, for example, polyoxyethylene (4) lauryl ether (HLB = 10.7, Nonion K-204, manufactured by NOF Corporation), polyoxyethylene (4). Oxyethylene (7) lauryl ether (HLB = 13.2, Nonion K-207, manufactured by NOF Corporation), polyoxyethylene (10) lauryl ether (HLB = 14.6, EMALEX 710, Nippon Emulsion Co., Ltd.) ), Polyoxyethylene (12) lauryl ether (HLB = 15.3, EMALEX 712, manufactured by Nippon Emulsion Co., Ltd.), polyoxyethylene (6) cetyl ether (HLB = 11.1, NIKKOL BC-5.5) , Nikko Chemicals Co., Ltd.), polyoxyethylene (13) cetyl ether (HLB = 15.6, nonionic) P-213, manufactured by NOF Corporation), polyoxyethylene (7) oleyl ether (HLB = 11.3, NIKKOL BO-7V, manufactured by Nikko Chemicals Co., Ltd.), polyoxyethylene (15) oleyl ether (HLB) = 14.6, Nonion E-215, manufactured by NOF Corporation), polyoxyethylene (7) stearyl ether (HLB = 11.3, Nonion S-207, manufactured by NOF Corporation), polyoxyethylene ( 15) Stearyl ether (HLB = 14.6, nonionic S-215, manufactured by NOF Corp.), polyoxyethylene (6) tridecyl ether (HLB = 12.2, nonionic T-206, NOF Corp.) Polyoxyethylene (12) tridecyl ether (HLB = 15.0, Nonion T-212, NOF Corporation), polyoxyethylene (10) Sostearyl ether (HLB = 12.9, Nonion IS-210, manufactured by NOF Corporation), polyoxyethylene (15) isostearyl ether (HLB = 14.5, Nonion IS-215, manufactured by NOF Corporation) ), Polyoxyethylene (10) behenyl ether (HLB = 12.0, nonion B-210, manufactured by NOF Corporation), polyoxyethylene (20) behenyl ether (HLB = 14.9, nonion B-220) NOF Corp.), polyoxyethylene (24) polyoxypropylene (13) decyltetradecyl ether (HLB = 10.8, Unilube 50MT-2200B, NOF Corp.), polyoxyethylene (20) Polyoxypropylene (6) decyltetradecyl ether (HLB = 11.3, Unilube MT-0620B, JP Co., Ltd.), polyoxyethylene (30) polyoxypropylene (6) decyltetradecyl ether (HLB = 13.2, Unilube MT-0630B, manufactured by NOF CORPORATION), polyoxyethylene (40) cured castor Oil (HLB = 13.1, UNIOX HC-40, manufactured by NOF Corporation), polyoxyethylene (60) hardened castor oil (HLB = 14.8, UNIOX HC-60, manufactured by NOF Corporation) ), Polyoxyethylene (10) phytosteryl ether (HLB = 10.9, NIKKOL BPS-10, manufactured by Nikko Chemicals Co., Ltd.), polyoxyethylene (30) phytosteryl ether (HLB = 15.6, NIKKOL BPS-) 30, Nikko Chemicals Co., Ltd.).

Among them, more preferably, polyoxyethylene (20-30) polyoxypropylene (5-15) decyltetradecyl ether, polyoxyethylene (40-60) hydrogenated castor oil, polyoxyethylene (10-30) phytosteryl Ruether.
One of these nonionic surfactants (B) can be used alone or in combination of two or more.

<Polyhydric alcohol (C)>
The polyhydric alcohol (C) used in the present invention is a dihydric or higher alcohol, preferably a dihydric or trihydric alcohol. The carbon number of the polyhydric alcohol (C) is, for example, 2 to 10, and preferably 2 to 6.
Examples of the polyhydric alcohol (C) include ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, glycerin and the like, and preferably 1,3-butylene glycol and glycerin.
One of these polyhydric alcohols (C) can be used alone or in combination of two or more. For example, a mixed solution composed of 25 to 75% by mass of glycerin and 75 to 25% by mass of 1,3-butylene glycol and having a total content of glycerin and 1,3-butylene glycol of 100% by mass can be used. .

<Water (D)>
The water (D) used in the present invention includes purified water, distilled water, ion-exchanged water and the like.
When the composition for emulsifying a nanoemulsion of the present invention contains a polyhydric alcohol (C) and water (D), the lipophilic-hydrophilic balance of the nonionic surfactant (B) is adjusted, and the nonionic surfactant (B) is adjusted. An infinite aggregate of the cationic surfactant (B) can be formed. In this infinite association, the average curvature of the nonionic surfactant (B) becomes zero, and the oil phase and the aqueous phase are in a continuous state. This state is called a bicontinuous microemulsion.

In the composition for nanoemulsion emulsification of the present invention, the mass ratio of each component satisfies the following conditions.
The mass ratio of the copolymer (A) to the nonionic surfactant (B), that is, (A) / (B) is from 0.1 to 0.7, preferably from 0.2 to 0.6. .
The mass ratio of the polyhydric alcohol (C) to the total of the copolymer (A) and the nonionic surfactant (B), that is, (C) / [(A) + (B)] is 3 to 8, Preferably it is 4-5.
The mass ratio of water (D) to the sum of the copolymer (A) and the nonionic surfactant (B), that is, (D) / [(A) + (B)] is 0.2 to 1.2. And preferably 0.6 to 0.8.
If the ratio is out of the range, a bicontinuous microemulsion may not be easily obtained even when emulsified with an oil component, which is the component (E) described later, so that nanoemulsion fine particles may not be easily obtained.

[Bicontinuous microemulsion]
The bicontinuous microemulsion of the present invention is obtained by emulsifying the composition for emulsifying a nanoemulsion of the present invention and an oil component as the component (E). Hereinafter, the oil component as the component (E) may be referred to as an oil component (E).

  As the oil component (E), those which can be used in general cosmetics can be used, and examples thereof include hydrocarbon oils, ester oils, vitamins, hormones, whitening agents, anti-inflammatory and antihistamine agents, and antioxidants. Examples include agents, intercellular lipids, ultraviolet absorbers, various humectants, and various fragrances.

  Examples of the hydrocarbon oil include liquid paraffin, polybutene, hydrogenated polyisobutene, hydrogenated polydecene, squalane, squalene, pristane, light isoparaffin, light liquid isoparaffin, heavy liquid isoparaffin, tetradecene, isohexadecane, isododecane, α-olefin oligomer , Petrolatum, microcrystalline wax, paraffin, polyethylene, ceresin and the like.

  Ester oil is an oil agent having an ester group, and examples thereof include triglycerides of fatty acids and glycerin, oils and fats, and esters of amino acids or fatty acids and monohydric or higher alcohols.

  Examples of triglycerides include caproic acid, caprylic acid, capric acid, 2-ethylhexanoic acid, lauric acid, tridecanoic acid, isotridecanoic acid, myristic acid, palmitic acid, isopalmitic acid, stearic acid, isostearic acid, eicosanoic acid, and Henic acid, tetracosanoic acid, myristolenic acid, palmitoleic acid, oleic acid, elaidic acid, erucic acid, linoleic acid, linolenic acid, arachidonic acid, hydroxystearic acid, coconut oil fatty acid, palm kernel oil fatty acid, hardened palm kernel oil fatty acid, Examples thereof include triglycerides of glycerin and fatty acids such as palm oil fatty acid, tallow fatty acid, hardened tallow fatty acid, lard fatty acid, castor oil fatty acid, and hardened castor oil fatty acid.

  Examples of the fats and oils include fats and oils such as olive oil, sunflower oil, palm oil, palm kernel oil, safflower oil, castor oil, hardened castor oil, coconut oil, camellia oil, cocoa butter, shea butter and the like.

  Examples of the ester of an amino acid with a monohydric or higher alcohol include, for example, dihexyldecyl N-lauroyl-L-glutamate, diisostearyl N-lauroyl-L-glutamate, and bis (hexyldecyl / octyldodecyl) N-lauroyl-L-glutamate. Dioctyldodecyl N-lauroyl-L-glutamate, dioctyldodecyl N-stearoyl-L-glutamate, N-myristoyl-N-methyl-β-alanine phytosteryl, N-lauroyl-L-glutamate di (cholesteryl / behenyl / 2 -Octyldodecyl), N-lauroyl-L-glutamate di (phytosteryl / behenyl / 2-octyldodecyl), N-lauroyl-L-glutamate di (cholesteryl / 2-octyldodecyl), N-lauroyl-L-gluta Nsanji (phytosteryl / 2-octyldodecyl), N- such lauroyl -L- glutamic acid di (phytosteryl / behenyl / octyldodecyl / isostearyl) can be exemplified.

Examples of the ester of a fatty acid and a monohydric or higher alcohol include ethyl oleate, ethyl linoleate, isopropyl myristate, isopropyl palmitate, isopropyl isostearate, isopropyl lanolin fatty acid, cetyl 2-ethylhexanoate, and 2-ethylhexanoic acid. Isocetyl, stearyl 2-ethylhexanoate, isostearyl 2-ethylhexanoate, cetyl palmitate, 2-ethylhexyl palmitate, 2-hexyldecyl isostearate, isostearyl isostearate, trimethylolpropane triisostearate, myristic acid Myristyl, cetyl myristate, octyl dodecyl myristate, isostearyl myristate, isosetyl myristate, hexyl laurate, decyl oleate, olein Octyldodecyl, isostearyl pivalate, isopropyl isostearate, isononyl isononanoate, 2-ethylhexyl isononanoate, isodecyl isononanoate, isotridecyl isononanoate, octyldodecyl erucate, neopentyl glycol didecanoate, pentaerythrityl tetraethylhexanoate, malate Diisostearyl, didecyl adipate, glyceryl isostearate, hydrogenated castor oil isostearate, cholesteryl isostearate, batyl isostearate, phytosteryl isostearate, octyl oxystearate, dihydrocholesteryl oleate, phytosteryl oleate, hydrogenated castor oil stearate, Cholesteryl soft lanolin fatty acid, cholesteryl hydroxystearate, hydroxy Phytosteryl tearate, dipentaerythritol hexaoxystearate, castor oil monohydroxystearic acid, isostearyl lanolin fatty acid, isopropyl lanolin fatty acid, octyldodecyl lanolin fatty acid, cholesteryl stearate, lanolin fatty acid cholesteryl, cetyl ricinoleate, dioctyl succinate , Cetyl lactate, propylene glycol dicaprylate, propylene glycol dicaprate, propylene glycol dinonanoate, propylene glycol di (caprylate / caprate), propylene glycol distearate, propylene glycol diisostearate, and propylene glycol dioleate. In addition, waxes such as beeswax, mokuro, carnauba wax, lanolin, candelilla wax and jojoba oil can also be used.
One of these may be used alone or in combination of two or more as the ester oil.

  Preferred ester oils include, for example, triglycerides of fatty acids having 6 or more carbon atoms, fats and oils, cetyl 2-ethylhexanoate, isocetyl 2-ethylhexanoate, isopropyl palmitate, 2-ethylhexyl palmitate, isopropyl isostearate, and isostearic acid. 2-hexyldecyl, octyldodecyl myristate, isopropyl myristate, isostearyl myristate, isocetyl myristate, isononyl isononanoate, 2-ethylhexyl isononanoate, isodecyl isononanoate, isotridecyl isononanoate, beeswax, mocro, phytosteryl hydroxystearate, N-myristoyl-N-methyl-β-alanine phytosteryl, N-lauroyl-L-glutamate di (cholesteryl / behenyl / 2-octane) Rudodecyl), N-lauroyl-L-glutamate di (phytosteryl / behenyl / 2-octyldodecyl), N-lauroyl-L-glutamate di (cholesteryl / 2-octyldodecyl), N-lauroyl-L-glutamate di (phytosteryl / 2-octyldodecyl), di (phytosteryl / behenyl / 2-octyldodecyl / isostearyl) N-lauroyl-L-glutamate and the like.

  Examples of the vitamins include vitamin A and its derivatives, vitamin B2 fat-soluble derivatives, vitamin B6 fat-soluble derivatives, vitamin C fat-soluble derivatives, vitamin C amphiphilic derivatives such as trisodium ascorbyl palmitate, vitamin D, Vitamin E and its derivatives such as tocopherol and tocopherol acetate, vitamin H, fat-soluble pantothenic acid derivatives, coenzyme Q10 (vitamin Q) and the like can be mentioned.

Hormones include, for example, cortisone, hydrocortisone, estradiol, estrone and the like.
Examples of whitening agents include kojic acid, placenta extract, arbutin, ellagic acid, lucinol, linoleic acid and the like.
Examples of the anti-inflammatory and antihistamines include glycyrrhetinic acid and its derivatives, glycyrrhizic acid and its derivatives, allantoin, hydrocortisone acetate, prednisolone and the like.
Examples of the antioxidants (antiaging agents) include antioxidants such as polyphenols, carotenoids, and flavonoids; N-methyl-L-serine, ursolic acid, and the like.
Examples of the intercellular lipids include ceramide and cholesterol.
Examples of the ultraviolet absorbers include a paraaminobenzoic acid derivative, a cinnamic acid derivative, a benzophenone derivative, and a salicylic acid derivative.
Examples of the humectant include a hyaluronic acid derivative, a collagen derivative, an elastin derivative, and a keratin derivative.
Examples of the flavors include various plant extracts and limonene.
One of these oily components can be used alone or in combination of two or more.

  The mixing amount of the oil component (E) varies depending on the type of the oil component (E), but is preferably 0.05 to 30 parts by mass, particularly preferably 1 to 20 parts by mass, per 100 parts by mass of the nanoemulsion emulsifying composition. It is 2 parts by mass, more preferably 2 to 10 parts by mass.

(Cosmetics)
The cosmetic of the present invention comprises a nanoemulsion obtained by diluting the bicontinuous microemulsion of the present invention with water.
The amount of water used for dilution is, for example, 50 to 99.9% by mass, and preferably 80 to 97% by mass, based on the total amount of the cosmetic.
When the nanoemulsion is 100% by mass, the amount of the oil component (E) is preferably 0.1 to 1.0% by mass, particularly preferably 0.2 to 0.5% by mass. Dilute.

  The cosmetic of the present invention forms a bicontinuous microemulsion by mixing and emulsifying the composition for nanoemulsion emulsification containing the components (A) to (D) in the above mass ratio and the oily component (E). (Step (I)), and a step (Step (II)) of diluting the bicontinuous microemulsion obtained in Step (I) with water, in order.

The cosmetic of the present invention is preferably produced by a method having the following steps (I) and (II).
Step (I): Step of mixing component (A), component (B), component (C) and component (D) with component (E) to prepare a bicontinuous microemulsion Step (II): Step ( Step of diluting the bicontinuous microemulsion obtained in I) with water to form a nanoemulsion

By forming a bicontinuous microemulsion in the step (I), the amount of the oil component (E) included in the polymer nanosphere can be increased.
A bicontinuous microemulsion is formed by mixing the components (A) to (E) and stirring at a temperature of usually 1 to 95 ° C, preferably 10 to 90 ° C.

  The water used for the dilution in the step (II) includes purified water, distilled water, ion-exchanged water and the like as in the case of the water (D). The temperature at the time of dilution with water is usually 1 to 95 ° C, preferably room temperature (1 to 30 ° C), and particularly preferably 15 to 25 ° C.

The nanoparticle (nanosphere) constituting the nanoemulsion obtained by the present invention preferably has a particle size of 5 to 500 nm, but is more preferably 300 nm or less from the viewpoint of enhancing the feeling of use of the cosmetic. If the particle size of the nanoparticles is too large, the nanoparticles are likely to aggregate and the stability of the dispersion is reduced, and when used in cosmetics, a rough feeling may be easily felt. If the particle size of the nanoparticles is too small, the stability may be deteriorated.
The particle size of the nanoparticles contained in the cosmetic of the present invention can be measured, for example, using a device such as a commercially available particle size distribution analyzer, using a principle such as a dynamic light scattering method. The average particle diameter measured by this method can be used as the particle diameter of the nanoparticle according to the present invention. The average particle size is calculated from the average value of the volume-particle size distribution function, assuming that the distribution function is a Gaussian distribution. The particle size of the nanoparticles can be adjusted to 5 to 500 nm by appropriately performing the method for producing the nanoparticles described above.

  The cosmetics of the present invention may optionally contain additives commonly used in cosmetics, as necessary, in addition to the nanoparticles. The additive is not particularly limited as long as the object of the present invention is not hindered, and includes, for example, oils, surfactants, humectants, thickeners, coloring materials, alcohols, ultraviolet ray protective agents, amino acids, vitamins, Whitening agents, organic acids, inorganic salts, enzymes, antioxidants, stabilizers, preservatives, bactericides, anti-inflammatory agents, skin activators, agents for promoting blood circulation, antiseborrheic agents, anti-inflammatory agents, sequestration, etc. Agents, pH adjusters, astringents, cooling agents, fragrances, pigments and the like.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples.
The blending amounts in the examples and comparative examples are% by mass. The residue is a numerical value such that the sum of all components is 100% by mass.

[Examples 1 to 9]
Using the compositions shown in Table 1, a composition for emulsifying a nanoemulsion and a nanoemulsion (cosmetic) were produced by the following production method, and the storage stability of the cosmetic was evaluated. The results are also shown in Table 1.

[Comparative Examples 1 to 14]
Using the compositions described in Tables 2 and 3, a composition for emulsifying a nanoemulsion and a nanoemulsion (cosmetic) were produced by the following production methods, and the storage stability of the cosmetic was evaluated. The results are shown in Tables 2 and 3.

<Production method>
Step I: Each raw material shown in the column of composition for nanoemulsion emulsification in each table was charged into a beaker and stirred at 80 ° C. with a stirrer.
Step II: The composition prepared in step I was diluted with water at room temperature to obtain a cosmetic comprising an O / W emulsion.

<Stability>
50 g of each manufactured cosmetic was filled in a 100 cc screw tube, sealed, and stored at room temperature. Immediately after the production, the next day after the production, one week after the production, and one month after the production, the appearance of the sample was confirmed and evaluated according to the following criteria.
：: A solution that has transmitted blue and pale ×: A solution in which creaming or precipitation has occurred

  The mass ratios (A) / (B), (C) / [(A) + (B)], (A), (B), (C), and (D) of the composition for emulsification. D) / [(A) + (B)] is shown in each table. In addition, when the component (A ') was used instead of the component (A), and when the component (B') was used instead of the component (B), the mass ratio replaced with these components was described.

For the preparation of the compositions in Table 1, CERACUTE-L (manufactured by NOF CORPORATION, containing (glycerylamidoethyl methacrylate / stearyl methacrylate) copolymer, glycerin, 1,3-butylene glycol), CERACUTE -F (manufactured by NOF Corp., (glycerylamidoethyl methacrylate / stearyl methacrylate) copolymer), NIKKOL BPS-20 (manufactured by Nikko Chemicals Co., Ltd., PEG-20 phytosterol), UNIOX 50MT-2200B ( NOP Co., Ltd., PPG-13 decyltetradeceth-24), UNIOX HC-40 (NOF Corp., PEG-40 hydrogenated castor oil), Pearl Dream EX (NOF Corp., Hydrogenated polyisobutene), Unilube MB-816 (manufactured by NOF CORPORATION, ethylhexyl palmitate), panassate 810 (Nichiyu Corporation, tri (capryl / capric acid) glyceryl), Sarakos FH (Nisshin Oillio Group Co., Ltd., phytosteryl hydroxystearate), Planool-MAS (Nippon Seika Co., Ltd., macadamia nut fatty acid) Phytosteryl).
In the case where CERACUTE-F was used as the (glycerylamidoethyl methacrylate / stearyl methacrylate) copolymer, it was preliminarily mixed with the polyhydric alcohol of the component (C) and then mixed with the other components shown in Step I.

  In preparing the compositions in Table 2, in addition to the above components, the (2-methacryloyloxyethyl phosphorylcholine / butyl methacrylate) copolymer of Production Example 1 below and the methacryloylethyl phosphorylcholine polymer of Production Example 2 below were used. Was. Each powder of these polymers and copolymers was produced according to the method described below. CAE (Cocoylarginine ethyl PCA, manufactured by Ajinomoto Healthy Supply Co., Ltd.) was used.

<Production Example 1>
Lipidure-PMB (manufactured by NOF CORPORATION) is freeze-dried, and a (2-methacryloyloxyethyl phosphorylcholine / butyl methacrylate) copolymer (constituent unit (molar ratio of 2-methacryloyloxyethyl phosphorylcholine: butyl methacrylate = 80: 20) ) Was obtained.

<Production Example 2>
Lipidure-HM (manufactured by NOF Corporation) was freeze-dried to obtain a methacryloyloxyethyl phosphorylcholine polymer powder.

  For the preparation of the compositions in Table 3, in addition to the above components, EMALEX PEIS-20EX (manufactured by Nippon Emulsion Co., Ltd., PEG-20 stearic acid), EMALEX HC-50 (manufactured by Nippon Emulsion Co., Ltd., PEG- Nonionic M-203 (manufactured by NOF Corporation, Milles-3) and Nonion LT-280 (manufactured by NOF Corporation, PEG-80 laurate sorbitan) were used, respectively.

  When the polymer nanosphere containing the oil component (E) is formed, the particle size is 300 nm or less, and the cosmetic of the O / W emulsion has a pale white appearance. Therefore, from the results in Table 1, it can be seen that the cosmetics of Examples 1 to 9 are cosmetics containing polymer nanospheres containing a large amount of various types of oily components (E).

On the other hand, examples (Comparative Examples 1 and 2) containing another (co) polymer instead of the component (A), and examples containing a cationic surfactant instead of the component (B) ( Comparative Example 3) did not form polymer nanospheres.
The mass ratio (C) / [(A) + (B)] or (D) / [(A) + (B)] of the components (A) to (D) of the composition for emulsification is the present invention. Examples out of the specified range (Comparative Examples 4 to 7), examples in which the mass ratio (A) / (B) of the component (A) and the component (B) was out of the specified range of the present invention (Comparative Example 8, and 9), an example in which the HLB of the component (B) is out of the range of 10 to 16 (Comparative Examples 10 and 11), and an emulsifying composition having a different composition from the present invention without using the component (D) in the step (I). In the examples prepared from the products (Comparative Examples 12 to 14), no polymer nanospheres were formed.
It should be noted that Comparative Examples 1 to 14 did not form polymer nanospheres immediately after production, and were not evaluated thereafter.

  Hereinafter, Formulation Examples of the emulsified cosmetic for skin comprising the nanoemulsion according to the present invention will be described. In addition, content is a mass%.

Claims (2)

A bicontinuous microparticle comprising a nanoemulsion emulsifying composition comprising the following components (A) to (D), wherein the mass ratio of each component satisfies the following conditions, and an oil component as the component (E) is emulsified. A cosmetic comprising a nanoemulsion obtained by diluting an emulsion with water .
(A) / (B) = 0.1-0.7
(C) / [(A) + (B)] = 3 to 8
(D) / [(A) + (B)] = 0.2 to 1.2
Component (A): Consists of a structural unit (a1) represented by the following formula (1) and a structural unit (a2) represented by the formula (2), and the molar ratio of the structural unit (a1) :( a2) is 40. : A copolymer having a weight average molecular weight of 5,000 to 5,000,000, which is 60 to 80:20.

(In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents — (CH ₂ ) n—, and n is an integer of 1 to 4.)

(In the formula, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents a hydrocarbon group having 12 to 24 carbon atoms.)
(B) Component: Nonionic surfactant having an HLB value of 10 to 16 (C) Component: Polyhydric alcohol (D) Component: Water The method for producing a cosmetic according to claim 1 , comprising the following step (I) and step (II).
Step (I): (A) component, (B) component, (C) component, (D) component and (E) a Ingredient mixing, process step of preparing a bicontinuous microemulsion (II): step (I Step of diluting the bicontinuous microemulsion obtained in the above) with water to form a nanoemulsion