JP2007308384A - Emulsion type external preparation for skin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for strengthening the interfaces of an emulsion and preventing the collapse of the emulsion in a water-in-oil emulsion type external preparation for skins, containing an organic-modified clay mineral. <P>SOLUTION: This water-in-oil emulsion type external preparation for the skins is characterized by comprising (1) an organic-modified clay mineral and (2) a polyglycerol-modified silicone. The external preparation for the skins preferably further contains L-carnitine and/or its salt, and also further contains dimethicone or cyclomethicone in an amount of 15 to 30 mass%. The mass ratio of the organic-modified clay mineral : the L-carnitine and/or its salt is preferably 1:1 to 3:1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a skin external preparation, and more particularly to a skin external preparation suitable for a skin external preparation in the form of a water-in-oil emulsifier.

  The water-in-oil emulsion has oily components in the continuous phase, and therefore has higher moisture retention due to the blocking effect than the oil-in-water emulsion, and has excellent properties for transdermal absorbability of the oily active ingredient. Yes. On the other hand, as a feeling of use, it has an oily and heavy defect. As a method of overcoming these disadvantages and taking advantage of the advantages of water-in-oil emulsions, various attempts have been made to produce high-in-water water-in-oil emulsions, and organic modifications such as dimethyl distearyl ammonium chloride-modified hectorite. Techniques for producing high-in-water water-in-oil emulsions using clay minerals have been developed (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3). However, even when such a technique is used, when a nonpolar oil such as silicone is contained in an amount of 15 to 30% by mass, the strength of the interface decreases, and if the emulsion is sheared, a phenomenon such as water separation occurs. There was a case to induce. Furthermore, when the emulsion is filled and stored in a resin container over a strength share, the container contacts the contents at the contact surface of the container against the background of such a decrease in the strength of the emulsion interface. In some cases, the emulsion was broken and the oil phase or the aqueous phase was liberated. That is, it can be said that the development of a means for strengthening the interface of the emulsion and preventing the emulsion from collapsing has been desired for the skin external preparation in the form of a water-in-oil emulsifier containing an organically modified clay mineral.

  On the other hand, polyglycerin-modified dimethylpolysiloxane is used for emulsification of cosmetics and the like as a silicone surfactant (see, for example, Patent Document 4 and Patent Document 5). However, there is no known technique for incorporating a water-in-oil emulsifier type cosmetic together with an organically modified clay mineral, and it is not known that such a composition forms an emulsion that does not easily collapse even with a share. A technique for incorporating a silicone-based surfactant into an oil-in-water cosmetic together with an organically modified clay mineral is known (see, for example, Patent Document 6, Patent Document 7, and Patent Document 8). Polyglycerin-modified dimethylpolysiloxane is not included in those used as the surfactant.

  On the other hand, L-carnitine and / or a salt thereof is known as an active ingredient for cosmetics having an anti-inflammatory action and the like, and a technique for inclusion in cosmetics is already known (for example, Patent Document 9, Patent Document 10 and Patent Document 11), and a technology of incorporating water-in-oil emulsifier type cosmetics together with polyglycerin-modified dimethylpolysiloxane and organically modified clay minerals is not known at all.

JP 2005-255623 A JP 2004-292373 A JP 2001-58937 A JP 2005-330243 A JP 2000-219609 A JP 2004-169015 A Japanese Patent Laid-Open No. 2003-146832 JP 2000-154115 A JP 2005-53835 A JP 2004-339144 A JP 2004-242509 A

  The present invention has been made under such circumstances, and in a water-in-oil emulsifier type skin external preparation containing an organically modified clay mineral, the interface of the emulsion is strengthened, and the emulsion is disintegrated. It is an object of the present invention to provide a preventive means.

In view of such a situation, in the topical preparation for skin external use in the form of a water-in-oil emulsifier containing an organically modified clay mineral, the present inventors have strengthened the interface of the emulsion and prevent the emulsion from collapsing. As a result of intensive research efforts, the inventors have found that the use of polyglycerin-modified dimethylpolysiloxane as a cosurfactant can prevent the emulsion from collapsing, thereby completing the invention. That is, the present invention is as follows.
(1) A skin external preparation in the form of a water-in-oil emulsifier comprising 1) an organically modified clay mineral and 2) a polyglycerin-modified silicone.
(2) The skin external preparation in the form of a water-in-oil emulsifier according to (1), further comprising L-carnitine and / or a salt thereof.
(3) The external preparation for skin according to (1) or (2), comprising 15 to 30% by mass of dimethicone or cyclomethicone.
(4) The ratio of the mass of the organically modified clay mineral to L-carnitine and a salt thereof is 1: 1 to 3: 1, according to any one of (1) to (3), Skin external preparation.
(5) The external preparation for skin according to any one of (1) to (4), further comprising 10 to 25% by mass of glycerin.

  ADVANTAGE OF THE INVENTION According to this invention, in the skin external preparation of the water-in-oil emulsifier form containing an organic modified clay mineral, the means of strengthening the interface of an emulsion and preventing the said emulsion collapse can be provided.

(1) Organically modified clay mineral which is an essential component of the external preparation for skin of the present invention The external preparation for skin of the present invention is characterized by containing an organically modified clay mineral as an essential component. Here, organic modification means that a part or all of the properties of an organic compound is made into a clay mineral by causing a part of the organic compound to form a strong or loose bond via a covalent bond or an ionic bond. This means that it is imparted to minerals. Examples of such modifications include a method of binding a quaternary amine group and an anion portion of a clay mineral, and a method of binding a carboxyl group and a cation portion of a clay mineral. A method of combining the group and the anion portion of the clay mineral is particularly preferable.

  Although it does not necessarily limit as a compound which has a quaternary amino group which modifies a clay mineral, The compound called quaternium is illustrated. Quotanium is a low molecular weight substituted quaternary ammonium salt, and is preferably a cosmetic raw material registered in International Standard Cosmetic Ingredients (INCI). Furthermore, the compound having a quaternary amino group that modifies the clay mineral is preferably a quaternium compound contained in a conventional external skin preparation among quaternium compounds. Preferred examples of the quaternium compound used in conventional external preparations for skin include stearyl trimethyl ammonium chloride and dimethyl distearyl ammonium chloride. Stearyl trimethyl ammonium chloride, dimethyl distearyl ammonium chloride and the like are preferable because they can form a stable water-in-oil emulsion structure together with clay minerals.

  On the other hand, as a clay mineral (unmodified clay mineral) modified with a compound having a quaternary amino group, any clay mineral contained in a conventional skin external preparation can be used without any particular limitation. Preferred clay minerals contained in conventional skin external preparations include smectite-type hectorite, bentonite and montmorillonite; kaolinite; illite; marine clay mineral (sea mud); desert rose clay mineral; Among these, bentonite, hectorite, montmorillonite or kaolinite which can stabilize the water-in-oil emulsion structure is preferably exemplified.

An example of a method for producing a clay mineral modified with a compound having a quaternary amino group contained in the external preparation for skin of the present invention will be described below.
The unmodified clay mineral is dispersed in a dispersion medium. The dispersant is preferably an aqueous solvent, and may be water. A compound having a quaternary amino group is further added to the dispersion containing the dispersed unmodified clay mineral and stirred well. The compound having a quaternary amino group may be added after being dissolved in water. The amount of the compound having a quaternary amino group to be added is preferably 0.1 to 20% by mass, and more preferably 0.5 to 15% by mass with respect to the amount of the dispersed unmodified clay mineral. This is because by taking such a configuration, a preferable feeling of use is exhibited in the emulsification system. After stirring, the dispersoid is filtered, dehydrated and dried to obtain the modified clay mineral in the present invention. Or the modified clay mineral in this invention can also be obtained by removing a dispersing agent by concentrating under reduced pressure without filtering a dispersoid, and making it dry. The obtained modified clay mineral is preferably pulverized to a desired size (preferably having a particle size of 1 to 1000 μm) and contained in the skin external preparation of the present invention.

  The modified clay mineral in the present invention can be prepared and used as described above, but a commercially available one can also be used. Some modified clay minerals on the market are used as external preparations for skin such as cosmetics. Preferable examples of commercially available modified clay minerals include dimethyl distearyl ammonium modified hectorite sold under the name “Benton 38V” by Elementis.

  In the skin external preparation of this invention, this component is contained preferably 0.5-10 mass%, More preferably, 1-5 mass% is contained. Such an ingredient acts as an emulsifier in the above-mentioned content range to form a high internal phase water-in-oil emulsifier form.

(2) Polyglycerin-modified dimethylpolysiloxane which is an essential component of the external preparation for skin of the present invention The external preparation for skin of the present invention contains polyglycerin-modified dimethylpolysiloxane as an essential component. Such components strengthen the emulsion interface made by the organically modified clay mineral, and have the effect of preventing the emulsion structure from collapsing due to physical stress such as shear. Such polyglycerin-modified methylpolysiloxanes are commercially available as raw materials for skin external preparations such as cosmetics, and such commercially available products can be purchased and used. Preferred examples of such commercially available products include “silicone KF6100” and “silicone KF6104” sold by Shin-Etsu Chemical Co., Ltd. In order to express the above-described action, 1 to 2% by mass of one or more selected from such polyglycerin-modified dimethylpolysiloxane is preferably 1 to 10% by mass, more preferably 2 to 8% by mass, based on the external preparation for skin. It is preferable to contain.

(3) External preparation for skin of the present invention The external preparation for skin of the present invention is characterized by containing the above essential components. Furthermore, L-carnitine and / or its salt are contained as a preferred component. L-carnitine has the structure shown below and has already been used as a raw material for cosmetics. Such a commercial product can be purchased and used. Moreover, since it is marketed also as a reagent, the acquisition is easy. In the present invention, such L-carnitine can be used as it is, or it can be contained in the form of a salt without any acid or the like. In storage, the salt state is more stable, so it is preferable to use a salt. As the salt, any salt that is usually used in an external preparation for skin can be used without particular limitation. For example, salts such as sulfates, hydrochlorides, nitrates, phosphates, carbonates, etc. Preferred examples include organic acid salts such as acid salts, tartrate salts, oxalate salts, lactate salts and acetate salts, and acidic amino acid salts such as glutamate salts and aspartates. Such a component has an effect of stabilizing the structure formed by the organically modified clay mineral, and has a function of improving the ability to include an oil-soluble active ingredient as a secondary function. In order to exert such an action, L-carnitine and / or a salt thereof may be contained in an amount of 0.1 to 10% by mass with respect to the total amount of the external preparation for skin, in terms of L-carnitine equivalent. Preferably, the content is 0.5 to 5% by mass. This is because if the amount is too small, the above effect may not be achieved, and if the amount is too large, the emulsification system may be damaged.

Ｌ−カルニチン

L-carnitine

  Moreover, in the skin external preparation of this invention, it is preferable that it is a water-in-oil emulsifier form. This is because the organically modified clay mineral, which is an essential component, is very suitable for producing a water-in-oil emulsifier type composition. In particular, a high internal phase water-in-oil emulsifier form is preferred. Here, the high internal phase water-in-oil emulsifier form means that the sum of the mass of water, the mass of ethanol, and the mass of polyhydric alcohol exceeds 50 mass%. In addition, as described above, when taking the water-in-oil emulsifier form, in order to compensate for the drawbacks of the feeling of use and finish of the water-in-oil emulsifier form, silicone (not an essential component) The glycerin-modified dimethylpolysiloxane is not included. The silicone content is preferably 10 to 35% by mass, more preferably 20 to 30% by mass. Among these, dimethicone or cyclomethicone is preferably 10 to 30% by mass, and more preferably 15 to 25% by mass. In particular, the mass of cyclomethicone is preferably 50% or more with respect to the sum of the masses of dimethicone and cyclomethicone.

  The skin external preparation of the present invention can contain a stable oil-soluble active ingredient, particularly, a solid oil-soluble active ingredient in the system by taking the above-described configuration. Examples of such active ingredients include triterpenic acids such as ursolic acid, oleanolic acid, and betulinic acid, derivatives of alkyl esters, alkenyl esters, and aromatic esters of the above-mentioned triterpenic acids, sphingosines, ceramides, phytosterols, phytosterols. Preferable examples include phytosterol glycosides such as glucoside. The phytosterol is a generic name for plant sterols, and the plant sterols include stigmasterol, campesterol, sitosterol, and the like, and these are collectively called phytosterols. As phytosterols, there are many cases where a sterol fraction containing a plurality of phytosterols is taken out from a plant body such as wheat germ and used, and a cosmetic raw material obtained by purifying only such a fraction is also commercially available, and the present invention is concerned. Commercial raw materials can be purchased and used. Examples of such commercially available raw materials include “phytosterol” sold by Okayasu Shoten Co., Ltd. The preferable content of such an oil-soluble active ingredient, particularly a solid oil-soluble ingredient, is 0.05 to 0.5% by mass.

  In addition to the components described above, the external preparation for skin of the present invention can contain optional components that are usually used in external preparations for skin. The external preparation for skin of the present invention can contain, in addition to such components, optional components that are usually used in external preparations for skin. Such optional ingredients include, for example, macadamia nut oil, avocado oil, corn oil, olive oil, rapeseed oil, sesame oil, castor oil, safflower oil, cottonseed oil, jojoba oil, coconut oil, palm oil, liquid lanolin, hydrogenated coconut oil Oil, wax, oil such as beeswax, canola wax, carnauba wax, ibotarou, lanolin, reduced lanolin, hard lanolin, jojoba wax, liquid paraffin, squalane, pristane, ozokerite, paraffin, ceresin, petrolatum , Hydrocarbons such as microcrystalline wax; higher fatty acids such as oleic acid, isostearic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, undecylenic acid; cetyl alcohol, stearyl alcohol, isostearyl Higher alcohols such as alcohol, behenyl alcohol, octyldodecanol, myristyl alcohol, cetostearyl alcohol; cetyl isooctanoate, isopropyl myristate, hexyldecyl isostearate, diisopropyl adipate, di-2-ethylhexyl sebacate, cetyl lactate, malic acid Diisostearyl, di-2-ethylhexanoic acid ethylene glycol, dicaprate neopentyl glycol, di-2-heptylundecanoic acid glycerin, tri-2-ethylhexanoic acid glycerin, tri-2-ethylhexanoic acid trimethylolpropane, tri Synthetic ester oils such as trimethylolpropane isostearate and pentane erythritol tetra-2-ethylhexanoate; dimethylpolysiloxane, methylphenylpoly Linear polysiloxanes such as oxane and diphenylpolysiloxane; cyclic polysiloxanes such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexanesiloxane; amino-modified polysiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, Oil agents such as silicone oils such as modified polysiloxanes such as fluorine-modified polysiloxanes; Anionic surfactants such as fatty acid soap (sodium laurate, sodium palmitate, etc.), potassium lauryl sulfate, triethanolamine ether of alkyl sulfates; Cationic surfactants such as stearyltrimethylammonium, benzalkonium chloride, laurylamine oxide; imidazoline-based amphoteric surfactants (2-cocoyl-2-imida Zolinium hydroxide-1-carboxyethyloxy disodium salt, etc.), betaine surfactants (alkyl betaine, amide betaine, sulfobetaine, etc.), and amphoteric surfactants such as acylmethyltaurine; sorbitan fatty acid esters (sorbitan) Monostearate, sorbitan sesquioleate, etc.), glycerin fatty acids (glyceryl monostearate, etc.), propylene glycol fatty acid esters (propylene glycol monostearate, etc.), hardened castor oil derivatives, glycerin alkyl ethers, POE sorbitan fatty acid esters (POE sorbitan monooleate, polyoxyethylene sorbitan monostearate, etc.), POE sorbite fatty acid esters (POE-sorbitol monolaurate, etc.), POE glycerin fatty acid ester Tells (POE-glycerol monoisostearate, etc.), POE fatty acid esters (polyethylene glycol monooleate, POE distearate, etc.), POE alkyl ethers (POE2-octyldodecyl ether, etc.), POE alkyl phenyl ethers (POE nonylphenyl) Ethers, etc.), Pluronic types, POE / POP alkyl ethers (POE / POP2-decyltetradecyl ether, etc.), Tetronics, POE castor oil / hardened castor oil derivatives (POE castor oil, POE hardened castor oil, etc.), Nonionic surfactants such as sucrose fatty acid ester and alkyl glucoside; polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, maltitol, propylene Polyhydric alcohols such as recall, dipropylene glycol, diglycerin, isoprene glycol, 1,2-pentanediol, 2,4-hexanediol, 1,2-hexanediol, 1,2-octanediol; sodium pyrrolidonecarboxylate Moisturizing ingredients such as lactic acid and sodium lactate; powders such as mica, talc, kaolin, synthetic mica, calcium carbonate, magnesium carbonate, anhydrous silicic acid (silica), aluminum oxide, barium sulfate, etc. whose surface may be treated Body, the surface may be treated, inorganic pigments such as bengara, yellow iron oxide, black iron oxide, cobalt oxide, ultramarine, bitumen, titanium oxide, zinc oxide; surface may be treated, mica Pearl agents such as titanium, fish phosphorus foil, bismuth oxychloride; red 202 which may be raked, red Color 228, Red 226, Yellow 4, Blue 404, Yellow 5, Red 505, Red 230, Red 223, Orange 201, Red 213, Yellow 204, Yellow 203, Blue 1 No., green 201, purple 201, red 204, etc .; organic powders such as polyethylene powder, polymethyl methacrylate, nylon powder, organopolysiloxane elastomer; para-aminobenzoic acid UV absorbers; anthranils Acid UV absorbers; salicylic acid UV absorbers; cinnamic acid UV absorbers; benzophenone UV absorbers; sugar UV absorbers; 2- (2′-hydroxy-5′-t-octylphenyl) benzo Ultraviolet absorbers such as triazole and 4-methoxy-4′-t-butyldibenzoylmethane; lower grades such as ethanol and isopropanol Alcohols; vitamin A or derivatives thereof, vitamin B6 hydrochloride, vitamin B6 tripalmitate, vitamin B6 dioctanoate, vitamin B2 or derivatives thereof, vitamin B such as vitamin B12, vitamin B15 or derivatives thereof; α-tocopherol, β- Preferred examples include vitamins such as tocopherol, γ-tocopherol, vitamin E acetate and the like, vitamins D, vitamin H, pantothenic acid, panthetin, pyrroloquinoline quinone, and the like; and antibacterial agents such as phenoxyethanol.

  Among such optional components, particularly preferred are polyhydric alcohols that can stabilize the emulsified state. Particularly preferred are glycerin, diglycerin, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol, and isoprene glycol. Such a component may contain only one species or may contain two or more species in combination. The preferred content is 10 to 30% by mass, more preferably 15 to 25% by mass, based on the total amount of the external preparation for skin, as a total amount.

  The external preparation for skin of the present invention can be produced by treating these components according to a conventional method. The external preparation for skin of the present invention is not particularly limited as long as it is externally applied to the skin. For example, basic cosmetics such as lotions, essences, emulsions, creams, packs, foundations, under-makeups, Makeup cosmetics such as control colors, highlights, UV protective cosmetics such as sun care milk and sun care cream, cleaning products such as rinses, shampoos, body shampoos, cosmetics for hair such as hair creams and hair packs, antifungals Skin external medicines, anti-inflammatory skin external medicines, steroid skin external medicines, external skin disinfectants, skin external goods, and the like can be suitably exemplified, among which cosmetics are preferable, and basic cosmetics are particularly preferable. In basic cosmetics, active ingredients can be efficiently transdermally absorbed, and there is a protective effect of the skin barrier function due to occlusive properties, and it is possible to suppress the enhancement of TEWL (transcutaneous water dispersion loss). .

  Hereinafter, the present invention will be described in more detail with reference to examples, but it goes without saying that the present invention is not limited to such examples.

  According to the formulation shown below, a cosmetic preparation in the form of a water-in-oil emulsifier, which is an external preparation for skin of the present invention, was produced. That is, the components of a and b are heated to 80 ° C., and k is kneaded to form a gel. C is added and dissolved therein, and the mixture is gradually added with emulsification and stirring. Upon cooling, a cosmetic 1 in the form of a water-in-oil emulsifier was obtained. In the same manner, Comparative Example 1 in which “Benton 38V” was replaced with “Silicone KF6100” and Comparative Example 2 in which “Silicone KF6100” was replaced with “Benton 38V” were also prepared.

<Test Example 1>
After the cosmetic 1, Comparative Example 1 and Comparative Example 2 were manufactured and stored at 20 ° C. for 24 hours, they were centrifuged at 1000 g for 5 minutes, filled in a resin container (polypropylene), and stored at 40 ° C. for 1 month. The sample was stored at 20 ° C. for 24 hours, the temperature was returned to 20 ° C., and the properties were observed. Properties were observed as a percentage of the separation height of the aqueous phase. The results are shown in Table 2. From this, it can be seen that Cosmetic 1, which is an external preparation for skin of the present invention, has a strong emulsion interface and has excellent stability.

  In the same manner as cosmetic 1, cosmetic 2 in the form of a water-in-oil formulation, which is an external preparation for skin of the present invention, was produced according to the following formulation. This was evaluated in Test Example 1 and the separation percentage of the aqueous phase was 0%. It turns out that the effect similar to the cosmetics 1 is acquired.

  In the same manner as cosmetic 1, cosmetic 3 in the form of a water-in-oil form, which is an external preparation for skin of the present invention, was produced according to the following formulation. This was evaluated in Test Example 1 and the separation percentage of the aqueous phase was 3%. It turns out that the effect similar to the cosmetics 1 is acquired. It can also be seen that the oil phase component preferably contains silicones not classified as surfactants such as dimethicone.

  Similarly to the cosmetic 1, a cosmetic 4 in the form of a water-in-oil, which is an external preparation for skin of the present invention, was produced according to the following formulation. This was evaluated in Test Example 1, and the separation percentage of the aqueous phase was 5%. This indicates that the skin external preparation of the present invention preferably contains carnitine chloride.

  In the same manner as cosmetic 1, cosmetic 5 in the form of water-in-oil, which is an external preparation for skin of the present invention, was produced according to the following formulation. This was evaluated in Test Example 1, and the separation percentage of the aqueous phase was 2%. This indicates that the skin external preparation of the present invention preferably contains carnitine chloride.

  In the same manner as cosmetic 1, in accordance with the following formulation, a skin external antifungal drug 1 in the form of a water-in-oil, which is an external preparation for skin of the present invention, was produced. This was evaluated in Test Example 1, and the separation percentage of the aqueous phase was 0%. It turns out that the effect similar to cosmetics 1 is acquired.

  The present invention can be applied to skin external preparations such as cosmetics and skin external medicines.

Claims (5)

A skin external preparation in the form of a water-in-oil emulsifier, comprising 1) an organically modified clay mineral and 2) a polyglycerin-modified silicone. Furthermore, L-carnitine and / or its salt are contained, The skin external preparation of the water-in-oil emulsifier form of Claim 1 characterized by the above-mentioned. The external preparation for skin according to claim 1 or 2, comprising 15 to 30% by mass of dimethicone or cyclomethicone. The skin external preparation according to any one of claims 1 to 3, wherein the ratio of the mass of the organically modified clay mineral to L-carnitine and a salt thereof is 1: 1 to 3: 1. Furthermore, 10-25 mass% of glycerol is contained, The skin external preparation in any one of Claims 1-4 characterized by the above-mentioned.