JP2007254308A - Oil-in-water type external preparation for skin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology to stably contain an oil-soluble effective ingredient in a high inner phase water-in-oil (W/O) emulsion using an organic-modified clay mineral, particularly at a sufficient amount of a solid oil-soluble effective ingredient. <P>SOLUTION: The organic-modified clay mineral (1) and L-carnitine and/or its salt (2) are contained in an external preparation for skin. Further, dimethicone or cyclomethicone (octamethylcyclotetrasiloxane) is preferably contained at 15-30 mass%, still further preferably, 1-10 mass% of a polyether-modified methylpolysiloxane is contained in the water-in-oil (W/O) type emulsion preparation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a skin external preparation such as cosmetics, 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, in the case where 15 to 30% by mass of a non-polar oil such as silicone is contained, there is a problem that exists in the case of lack of tolerance including an oil-soluble active ingredient. . The silicone relieves the oily feel of the water-in-oil emulsion and, in the case of volatile substances such as cyclomethicone such as decamethylpentacyclosiloxane, has the effect of suppressing the finished fat deposits. It was also a semi-essential component in the water-in-oil emulsion composition. That is, in a high internal phase water-in-oil emulsion using an organically modified clay mineral, a sufficient amount of an oil-soluble active ingredient that is stably soluble in the system, especially a solid oil-soluble active ingredient, particularly 0.05 mass It can be said that the development of the technology to be included is desired.

  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 4, (See Patent Documents 5 and 6), and it is not known to be blended in a water-in-oil emulsifier form, and in a high-in-water water-in-oil emulsion using an organically modified clay mineral, the oil is stably soluble in the system. It is not known at all that it has an effect of incorporating a sufficient amount of the active ingredient, especially, solid oil-soluble active ingredient.

JP 2005-255623 A JP 2004-292373 A JP 2001-58937 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 high internal phase water-in-oil emulsion using an organically modified clay mineral, an oil-soluble active ingredient that is stably soluble in the system, especially, solid oil-soluble It is an object of the present invention to provide a technique for incorporating a sufficient amount of the active ingredient.

In view of such a situation, the present inventors, in a high internal phase water-in-oil emulsion using an organically modified clay mineral, have a stable oil-soluble active ingredient in the system, especially a solid oil-soluble effective ingredient. As a result of earnest research efforts in search of a technique for incorporating a sufficient amount of ingredients, the presence of L-carnitine and / or a salt thereof increases the stability of the water-in-oil emulsion system, The inventors have found that the active ingredient can be stably included in the system and have completed the invention. That is, the present invention is as follows.
(1) An external skin preparation characterized by containing 1) an organically modified clay mineral and 2) L-carnitine and / or a salt thereof.
(2) The external preparation for skin according to (1), comprising 15 to 30% by mass of dimethicone or cyclomethicone.
(3) The skin external preparation according to (1) or (2), further comprising 1 to 10% by mass of a polyether-modified methylpolysiloxane.
(4) The external preparation for skin according to any one of (1) to (3), which is in the form of a water-in-oil emulsifier.
(5) 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 (4), Skin external preparation.
(6) In the case of producing a water-in-oil emulsion composition by emulsifying an oil phase containing dimethicone or cyclomethicone using an organically modified clay mineral, L-carnitine and / or a salt thereof is converted to an organically modified clay. The method for improving the stability of the water-in-oil emulsion composition, wherein an equivalent amount or 1/3 equivalent amount is added to the mass of the mineral.

  According to the present invention, in a high internal phase water-in-oil emulsion using an organically modified clay mineral, a sufficient amount of a stable oil-soluble active ingredient is included in the system, especially a solid oil-soluble active ingredient. Technology 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) L-carnitine 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 L-carnitine and / or a salt thereof as an essential 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 components have the effect of stabilizing the structure of the organically modified clay mineral and improving the ability to include oil-soluble active ingredients. 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

(3) The skin external preparation of this invention The skin external preparation of this invention contains the said essential component, It is characterized by the above-mentioned. In the external preparation for skin of the present invention, a water-in-oil emulsifier form is preferred. 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%. Further, as described above, when taking the water-in-oil emulsifier form, it is preferable to contain silicone in order to compensate for the drawbacks of the feeling of use and finish of the water-in-oil emulsifier form. Is preferably contained in an amount of 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. Examples of silicones other than dimethicone and cyclomethicone include polyether-modified methyl polysiloxanes such as POE-modified methyl polysiloxane, POP-modified methyl polysiloxane, and POP / POE-modified methyl polysiloxane, which may contain such components. This is preferable because the water-in-oil emulsion system can be stabilized. The preferable content of such polyether-modified methylpolysiloxane is more preferably 0.5 to 5% by mass and 1 to 3% by mass.

  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 KF6017” and Comparative Example 2 in which L-carnitine chloride was replaced with water were also prepared.

<Test Example 1>
Cosmetic 1, Comparative Example 1 and Comparative Example 2 were held at −10 for 24 hours, then heated to 5 ° C. over 24 hours, held at 5 ° C. for 24 hours, and cooled to −10 ° C. over 24 hours. It is a periodic temperature change storage, which is a cycle of the operation to be performed, stored in a winter aging box for 1 month, extended to a hemocytometer at 1 at 20 ° C., and observed 20 visual fields at a magnification of 100 times, The number of insoluble solids was counted and the average number per visual field was determined. In cosmetic 1, no precipitated solid was observed, but 5.6 in Comparative Example 1 and 9.1 in Comparative Example 2 were observed. From this, it can be seen that the cosmetic of the present invention is excellent in oil-soluble active ingredient retention effect.

  In the same manner as for cosmetic 1, according to the following formulation, cosmetics 2 to 8 in the form of water-in-oil, which is an external preparation for skin of the present invention, were produced. These were evaluated in the same manner as in Test Example 1, but no precipitated solid was observed in any of the samples. From this, it can be seen that the cosmetic of the present invention is excellent in oil-soluble active ingredient retention effect.

   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. These were evaluated in the same manner as in Test Example 1, but no precipitated solid was observed.

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

Claims (6)

A skin external preparation characterized by comprising 1) an organically modified clay mineral and 2) L-carnitine and / or a salt thereof. The external preparation for skin according to claim 1, comprising 15 to 30% by mass of dimethicone or cyclomethicone. Furthermore, 1-10 mass% of polyether modified methyl polysiloxane is contained, The skin external preparation of Claim 1 or 2 characterized by the above-mentioned. The skin external preparation according to any one of claims 1 to 3, which is in the form of a water-in-oil emulsifier. The skin external preparation according to any one of claims 1 to 4, 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. When an organic phase containing dimethicone or cyclomethicone is emulsified using an organically modified clay mineral to produce a water-in-oil emulsion composition, L-carnitine and / or a salt thereof is added to the mass of the organically modified clay mineral. On the other hand, the method for improving the stability of the water-in-oil emulsion composition is characterized by adding an equivalent amount or 1/3 equivalent amount.