JP2016088901A - Water-in-oil type emulsified composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-in-oil type emulsified composition in which two or more kinds of aqueous phases with different compositions exist in an oil, and in which temporal stability is improved.SOLUTION: The invention relates to a structure in which an aqueous phase is covered with a D phase film with high elasticity. The invention also relates to a water-in-oil type emulsified composition obtained by forming an emulsion by D-phase emulsification, resulting in having temporal stability even under high temperature condition. Preferably, the emulsion composition contains at least one or more kinds selected from polyhydric alcohol fatty acid ester, a silicone based surfactant, a cationic surfactant, an amphoteric surfactant, and an anionic surfactant, and also preferably contains a polyhydric alcohol. Moreover, the emulsion composition contains two or more kinds of aqueous phases with different compositions. Preferably the emulsion composition is an external preparation for skin and more preferably is a cosmetic.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water-in-oil type skin external composition, and particularly relates to a water-in-oil type emulsion composition in which two or more types of water phases having different compositions are present in the oil phase.

  The water-in-oil emulsion composition has a high blocking effect due to the presence of oily components in the continuous phase, and has advantages such as high moisture retention. There has been proposed an attempt to increase the transdermal absorbability of a water-soluble active ingredient while containing a vesicle in such a water-in-oil emulsion composition while being in the form of a water-in-oil emulsifier (for example, patent documents). 1).

  Further, a technique for stably containing two types of water-soluble active ingredients in a water-in-oil emulsion composition has been proposed (for example, see Patent Document 2).

JP 2007-308380 A JP2013-216640A

When the present inventors examined, the formulation of the said patent document 2 had room for improvement in temporal stability. Accordingly, an object of the present invention is to provide a water-in-oil emulsion composition with improved temporal stability, particularly a (W1 + W2) / O emulsion composition.
In this specification, W represents a water phase, W1 and W2 represent water phases having different compositions, and O represents an oil phase.

  The inventors of the present invention have advanced research to solve the above-mentioned problems, and conceived that a water-in-oil emulsion composition with improved stability over time can be obtained by forming an emulsion by D-phase emulsification. Was completed.

The present invention is a water-in-oil emulsion composition in which an aqueous phase is covered with a D-phase film. The water-in-oil emulsion composition of the present invention is one in which an emulsion is formed by D-phase emulsification. The water-in-oil emulsion composition of the present invention is at least one selected from polyhydric alcohol fatty acid esters, silicone surfactants, cationic surfactants, amphoteric surfactants, and anionic surfactants. It is preferable to contain. Moreover, it is preferable that the water-in-oil type emulsion composition of this invention contains a polyhydric alcohol. Furthermore, the water-in-oil emulsion composition of the present invention preferably contains two or more aqueous phases having different compositions. Moreover, the water-in-oil emulsion composition of the present invention is preferably a skin external preparation, and more preferably a cosmetic.
In the present specification, HLB (Hydrophilic-Lypophilic Balance) refers to a value calculated from the Griffin equation.

  According to the present invention, a water-in-oil emulsion composition having improved stability over time is provided. In the emulsified composition of the present invention, the aqueous phase is covered with a highly elastic D-phase film, and such an aqueous phase does not coalesce even when shearing force is applied. It becomes stable over time even under conditions.

The LSM observation photograph (400-times multiplication factor) of the (W1 + W2) / O type emulsion composition of Example 1. FIG.

  Hereinafter, although the water-in-oil type emulsion composition of this invention is demonstrated, the technical scope of this invention is not limited only to the following specific embodiments.

The emulsified composition of the present invention is a water-in-oil emulsified composition in which an aqueous phase is covered with a D-phase film.
The D phase is usually also referred to as a middle phase microemulsion phase, a bicontinuous phase, a sponge phase, a surfactant phase, a bicontinuous microemulsion phase, or the like. In the D phase, the number of associations of the surfactant molecules is remarkably increased, and the interfacial tension between the oil phase and the aqueous phase is lowered to form a continuous phase. Therefore, efficient emulsification is performed. Note that the D phase is different from the liquid crystal phase disclosed in Japanese Patent Application Laid-Open Nos. 2004-010549 and 2010-0667049.
In the emulsified composition of the present invention, since the D-phase film covering the aqueous phase has high elasticity, the aqueous phase does not coalesce even when a shearing force or the like is applied. As a result, the emulsion composition of the present invention is stable over time even under high temperature conditions.

The water-in-oil type emulsifier type may be a general W / O type, but in the present invention, it is a water-in-oil type emulsifier type containing two or more water phases having different compositions. May be. For example, an emulsified composition having two types of aqueous phases (W1 and W2) having different compositions, such as (W1 + W2) / O emulsion type, can be mentioned. Of course, the aspect which has three types of water phases (W1, W2, and W3) from which a composition differs may be sufficient.
By having two or more types of aqueous phases having different compositions, the environmental conditions of the aqueous phase can be made different, so that an optimum environment for each active ingredient included in the aqueous phase can be prepared.
In addition, as described above, the water-in-oil emulsion composition of the present invention is excellent in stability over time, and two or more types of water phases can be stably present in the composition without being united, An environment suitable for each active ingredient can be maintained.

The adjustment method of a W / O type emulsion composition is widely known in the said technical field.
As a method for preparing the (W1 + W2) / O emulsion composition, for example, as disclosed in Patent Document 2,
1) After preparing W1 / O emulsion composition, W2 is added to prepare (W1 + W2) / O emulsion composition, and 2) W1 / O emulsion composition and W2 / O emulsion composition are adjusted respectively. And (W1 + W2) / O method of preparing an emulsified composition by mixing.

The emulsion composition of the present invention can be prepared by forming an emulsion via the D phase (D phase emulsification) when the emulsion composition is prepared by the above method or the like.
Passing through the D phase can be confirmed by making the system a transparent or translucent appearance in the preparation process and forming a one-phase solution in which all the components to be blended are uniformly dissolved.
In the emulsion formed by D-phase emulsification, the emulsified droplets (aqueous phase) are covered with a D-phase film, and the emulsified droplet particles are very fine. Usually, the particle size of the emulsified droplets is 0.01 μm or more and 5 μm or less, preferably 2 μm or less, more preferably 1 μm or less, and still more preferably 0.5 μm or less.

Usually, a polyhydric alcohol is used to perform D-phase emulsification.
Examples of the polyhydric alcohol used in the emulsion composition of the present invention include polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, maltitol, propylene glycol, dipropylene glycol, diglycerin, isoprene glycol, Preferred examples include 1,2-pentanediol, 2,4-hexylene glycol, 1,2-hexanediol, 1,2-octanediol and the like. Among these, polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, multirole, and diglycerin are more preferable, and glycerin is particularly preferable.
The polyhydric alcohol can be used singly or in combination of two or more, and the total content thereof is preferably 1 to 50% by weight, more preferably 5 to 40% by weight, and more preferably 10 to 30% by weight of the total amount of the emulsified composition. Is more preferable.

Usually, a surfactant is used to perform D-phase emulsification.
Surfactants include anionic surfactants such as fatty acid soap (sodium laurate, sodium palmitate, etc.), potassium lauryl sulfate, triethanolamine ether of alkyl sulfate, stearyltrimethylammonium chloride, benzalkonium chloride, laurylamine Cationic surfactants such as oxides,
Betaine surfactants (alkyl betaines, amide betaines, sulfobetaines, etc.), imidazoline amphoteric surfactants (such as 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt), acylmethyl taurine Amphoteric surfactants such as
Polyethylene glycol fatty acid esters (polyethylene glycol monooleate, polyethylene glycol monostearate, polyethylene glycol monolaurate, etc.), sorbitan fatty acid esters (sorbitan monooleate, sorbitan monostearate, sorbitan monoisostearate, sorbitan monolaurate, sesquiolein Acid sorbitan, etc.), monoglycerin fatty acids (glyceryl laurate, glyceryl myristate, glyceryl stearate, glyceryl behenate, glyceryl isostearate, glyceryl isostearate, glycerin coconut oil fatty acid glycerine, glyceryl lanolin phosphate, etc.) , Polyglycerol fatty acids (diglyceryl stearate, diglyceryl oleate, diisostearate Glyceryl, tetraglyceryl stearate, tetraglyceryl oleate, hexaglyceryl laurate, decaglyceryl stearate), propylene glycol fatty acid esters (such as propylene glycol monostearate), hardened castor oil derivatives, glycerin alkyl ether, POE sorbitan fatty acid Esters (polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, Triisostearic acid polyoxyethylene sorbitan, etc.), POE sorbite fatty acid esters (POE-sorbitol) Monolaurate, etc.), POE glycerin fatty acid esters (polyoxyethylene glyceryl monomyristate, polyoxyethylene glyceryl monostearate, polyoxyethylene glyceryl monoisostearate, polyoxyethylene glyceryl triisostearate), POE fatty acid esters (POE monooleate, POE distearate, etc.), POE alkyl ethers (polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene behenyl ether, polyoxyethylene oleyl ether, polyoxyethylene hexyl decyl ether) , Polyoxyethylene isostearyl ether, polyoxyethylene octyldodecyl ether, polyoxy Tylene decyl pentadecyl ether, polyoxyethylene decyl tetradecyl ether, polyoxyethylene cholesteryl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene polyoxypropylene cetyl ether, polyoxyethylene polyoxypropylene decyl Tetradecyl ether, etc.), POE alkylphenyl ethers (POE nonylphenyl ether, etc.), polyoxyethylene fatty acid amides (lauric acid diethanolamide, coconut oil fatty acid diethanolamide, polyoxyethylene stearic acid amide, etc.), pluronic types, POE・ POP alkyl ethers (POE, POP2-decyltetradecyl ether, etc.), Tetronics, POE castor・ Hardened castor oil derivatives (POE castor oil, POE hardened castor oil, etc.), sucrose fatty acid ester, alkyl glucoside, polyoxyethylene sorbit beeswax, polyoxyethylene lanolin, polyoxyethylene lanolin alcohol, polyoxyethylene sorbitol lanolin, dimethyl lauryl Nonionic surfactants such as amine oxides,
Examples include PEG-10 dimethicone, PEG / PPG-20 / 20 dimethicone, silicone-13, laurylpolyglyceryl-3polydimethylsiloxyethyl dimethicone and the like, and among these, D-phase emulsification is efficient. From the viewpoint of performing well, a silicone-based surfactant is more preferable, and a polyether-modified silicone-based surfactant is more preferable.

Of these, from the viewpoint of efficiently performing D-phase emulsification, HLB (Hydrophilic-Lypophilic Balance) is preferably 3 or more and 8 or less, and more preferably 4 or more and 6 or less. Conventionally, there has been an example of producing an O / W type emulsifier form using D phase emulsification, but it has been difficult to produce a W / O type emulsifier form using D phase emulsification. This is presumably because the W / O emulsifier is generally easily dissolved in an oil agent, so that the surfactant molecules to be adsorbed on the oil / water interface have a strong tendency to dissolve in the oil phase in a monodispersed state. The present inventor has conceived that the use of the surfactant described above enables efficient D-phase emulsification in the production of the W / O emulsifier type.
Surfactant can be used combining 1 type (s) or 2 or more types arbitrarily, and the total content is 0.1-20 weight% of an emulsion composition whole quantity, 1-10 weight% is more preferable, 3-6 More preferred is weight percent.

The water-in-oil emulsion composition of the present invention can be suitably used for a skin external preparation and can be applied to cosmetics, quasi-drugs and pharmaceuticals. Ingredients can be included. Among these, it is preferable to apply to cosmetics, particularly skin care cosmetics.
When applied to cosmetics, it is possible to broadly blend the components normally used in cosmetics, and the dosage form and use are not limited at all. Hereinafter, the components that can be contained in the cosmetic when applied to the cosmetic will be described.
Examples of components usually used in cosmetics include various active ingredients, oily ingredients, thickeners, powders, ultraviolet absorbers, and organically modified clay minerals.
Examples of active ingredients include whitening ingredients, wrinkle-improving ingredients, anti-inflammatory ingredients, animal and plant extracts. An active ingredient may contain only 1 type and may contain 2 or more types.

The whitening component is not particularly limited as long as it is generally used in cosmetics. For example, 4-n-butylresorcinol, ascorbic acid glucoside, 3-O-ethylascorbic acid, tranexamic acid, arbutin, 1-triphenylmethylpiperidine, 1-triphenylmethylpyrrolidine, 2- (triphenylmethyloxy) ethanol, 2- (triphenylmethylamino) ethanol, 2- (triphenylmethyloxy) ethylamine, triphenylmethylamine, triphenyl Phenylmethanol, triphenylmethane and aminodiphenylmethane, N- (p-toluyl) cysteic acid, N- (p-methoxybenzoyl) cysteic acid, N-benzoyl-serine, N- (p-methylbenzoyl) serine, N- ( p-ethylbenzoyl) serine, N- (p-methoxybenzoyl) serine, N- (p-fluorobenzoyl) serine, N- (p-trifluoromethylbenzoyl) serine, N- (2-naphthoyl) serine, N- (p-methylbenzoyl)- O-methylserine, N- (p-methylbenzoyl) -O-acetylserine, N- (2-naphthoyl) -O-methylserine, kojic acid, 4-methoxysalicylic acid potassium salt, chamomile extract, melissa extract, artichoke extract, yuzu extract , Majorana extract, loquat leaf extract, cuckoo extract, aloe extract, chlorella extract and the like.
Content of the whitening component in cosmetics is 0.01-10 mass% normally, 0.1-10 mass% is preferable and 0.2-5 mass% is more preferable.

  The wrinkle improving component is not particularly limited as long as it is generally used in cosmetics. For example, vitamin A or a derivative thereof may be retinol, retinal, retinoic acid, tretinoin, isotretinoin, retinoic acid tocopherol, palmitic acid retinol, acetic acid retinol, ursolic acid benzyl ester, ursolic acid phosphoric acid ester, betulinic acid benzyl ester, benzylic acid Examples thereof include phosphate ester, sodium chondroitin sulfate, 2-methacryloyloxyethyl phosphorylcholine, assembly extract, ghetto leaf extract, hydrolyzed chickweed carrot root extract, cornflower extract and the like. Content of the wrinkle improvement component in cosmetics is 0.01-10 mass% normally, 0.1-10 mass% is preferable, and 0.2-5 mass% is more preferable.

The extracts derived from animals and plants are not particularly limited as long as they are generally used for pharmaceuticals, cosmetics, foods and the like. For example, akebi extract, asunaro extract, asparagus extract, avocado extract, achacha extract, almond extract, arnica extract, aloe extract, aronia extract, apricot extract, ginkgo biloba extract, Indian mushroom extract, fennel extract, udo extract, ages extract, sorghum extract , Enmezo extract, Ogon extract, Oat extract, Auren extract, Panax ginseng extract, Hypericum extract, Adrianthus extract, Orange extract, Oyster extract, Cuckoo extract, Chamomile extract, Carrot extract, Kawara mugwort extract, Licorice extract, Kiwi extract, Cucumber extract, Guava extract, Kujin extract, Gardenia extract, Kumazasa extract, Clara extract, Walnut extract, Grapefruit extract, Black rice , Chlorella extract, mulberry extract, caquette extract, gentian extract, gentian extract, Gennosho extract, tea extract, burdock extract, rice extract, fermented rice extract, rice fermented extract, rice germ oil, bilberry extract, salvia extract, bonito extract , Sasa extract, Hawthorn extract, Sansha extract, Salamander extract, Shiitake extract, Giant extract, Shikon extract, Perilla extract, Linden extract, Citrus extract, Peonies extract, Pepper extract, Ginger root extract, Birch extract, Japanese cedar extract, Stevia extract, Stevia fermentation , Kizuta extract, Hawthorn extract, Elderberry extract, Yarrow extract, Pepper extract, Sage extract, Mallow Kiss, Senkyu Extract, Sembura Extract, Sakuhakuhi Extract, Daiou Extract, Soybean Extract, Taiso Extract, Thyme Extract, Dandelion Extract, Tea Extract, Clove Extract, Chimpi Extract, Green Tea Extract, Capsicum Extract, Toki Extract, Tokinsenka Extract, Tonin Extract, Spruce Extract , Dokudami extract, tomato extract, natto extract, carrot extract, garlic extract, wild rose extract, hibiscus extract, bacmond extract, lotus extract, parsley extract, birch extract, hammamellis extract, cypress extract, hinoki extract, loquat extract, dandelion extract, fukinotou extract , Bukuryo extract, Butcher bloom extract, Grape extract, Grape seed extract, Loofah extract, Safflower extract, Peppermint extract, Bo Daiju extract, button extract, hop extract, pine extract, mayonnaise extract, maronier extract, mizuba sho extract, mukuroji extract, melissa extract, mozuku extract, peach extract, cornflower extract, eucalyptus extract, yukinoshita extract, yuzu extract, lily extract, yakuinin extract, mugwort extract, lavender Extracts such as extract, green tea extract, apple extract, rooibos tea extract, litchi extract, lettuce extract, lemon extract, forsythia extract, forsythia extract, rose extract, rosemary extract, roman chamomile extract, royal jelly extract, and bitumen extract are preferred. Can be mentioned.
Content of the animal and plant origin extract in cosmetics is 0.01-10 mass% normally, 0.1-10 mass% is preferable and 0.2-5 mass% is more preferable.

Examples of the anti-inflammatory component include clarinone, grabridine, glycyrrhizic acid, glycyrrhetinic acid, and the like, and preferred are glycyrrhizic acid and its salt, glycyrrhetinic acid alkyl and its salt, and glycyrrhetic acid and its salt.
Content of the anti-inflammatory component in cosmetics is 0.01-10 mass% normally, 0.1-5 mass% is preferable and 0.2-3 mass% is more preferable.

Examples of the oil component include polar oil, natural oil, hydrocarbon oil, and silicone oil.
Polar oils include synthetic ester oils such as isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, lactic acid Cetyl, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, cholesteryl 12-hydroxystearylate, ethylene glycol di-2-ethylhexylate, dipentaerythritol fatty acid ester, N-alkylglycol monoisostearate, neopentyl dicaprate Glycol, diisostearyl malate, glycerin di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexylate May be mentioned trimethylolpropane triisostearate, tetra-2-ethylhexyl acid pentane erythritol, tri-2-ethylhexyl acid glycerin, trimethylolpropane triisostearate.

  Furthermore, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glyceryl trimyristate, glyceride tri-2-heptylundecanoate, castor oil fatty acid methyl ester, oleic acid oil, cetostearyl alcohol, acetoglyceride, palmitic acid 2 -Heptylundecyl, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyl myristate Decyl, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, triethyl citrate, octylme Kishishin'nameto, etc. may also be mentioned.

  Natural oils include avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, persic oil, wheat germ oil, sasanca oil, castor oil, flaxseed oil, Safflower oil, cottonseed oil, eno oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, cinnagari oil, Japanese kiri oil, jojoba oil, germ oil, triglycerin, trioctanoic acid glycerin, triisopalmitic acid glycerin Etc.

Examples of the hydrocarbon oil include isododecane, isohexadecane, squalane, petrolatum, hydrogenated poly (C6-12 olefin), hydrogenated polyisobutene, and petrolatum is preferable.
Examples of the silicone oil include cyclopentasiloxane, decamethylcyclopentasiloxane, caprylylmethicone, dimethicone, (dimethicone / vinyl dimethicone) crosspolymer, (dimethicone / phenylvinyldimethicone) crosspolymer, and the like. Highly polymerized dimethicone with 10,000 mPas is preferred.

Thickeners include guar gum, quince seed, carrageenan, galactan, gum arabic, pectin, mannan, starch, xanthan gum, curdlan, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, methylhydroxypropylcellulose, chondroitin sulfate, dermatan sulfate, glycogen, Heparan sulfate, hyaluronic acid, sodium hyaluronate, tragacanth gum, keratan sulfate, chondroitin, mucoitin sulfate, hydroxyethyl guar gum, carboxymethyl guar gum, dextran, kerato sulfate, locust bean gum, succinoglucan, caronic acid, chitin, chitosan, carboxymethyl Chitin, agar, polyvinyl alcohol, polyvinylpyrrolidone, carboxyvinyl polymer, al Le-modified carboxyvinyl polymers, sodium polyacrylate, polyethylene glycol, and bentonite.

  As powders, the surface may be treated, mica, talc, kaolin, synthetic mica, calcium carbonate, magnesium carbonate, silicic anhydride (silica), aluminum oxide, barium sulfate, etc. May be treated, bengara, yellow iron oxide, black iron oxide, cobalt oxide, ultramarine, bitumen, titanium oxide, zinc oxide inorganic pigments, surface may be treated, mica titanium, fish phosphorus foil, Pearl agents such as bismuth oxychloride, red 202, red 228, red 226, yellow 4, blue 404, yellow 5, red 505, red 230, red 223 which may be raked No., Orange No. 201, Red No. 213, Yellow No. 204, Yellow No. 203, Blue No. 1, Green No. 201, Purple No. 201, Red No. 204, organic dyes, polyethylene powder, polymeta Methyl acrylic acid, nylon powder, organic powders such as organopolysiloxane elastomers, and the like.

  Examples of the UV absorber include paraaminobenzoic acid UV absorbers, anthranilic acid UV absorbers, salicylic acid UV absorbers, cinnamic acid UV absorbers, benzophenone UV absorbers, sugar UV absorbers, 2- (2 UV absorbers such as' -hydroxy-5'-t-octylphenyl) benzotriazole, 4-methoxy-4'-t-butyldibenzoylmethane, and the like.

  Examples of the organoclay mineral include dimethyl distearyl ammonium modified hectorite, benzyl dimethyl stearyl ammonium modified hectorite, and trioctylmethyl ammonium hectorite.

  Hereinafter, although an example is given and the present invention is explained still in detail, the present invention is not limited to these.

<1> Preparation of (W1 + W2) / O-type Emulsion Composition The (W1 + W2) / O-type emulsion composition of the present invention was prepared according to the formulation shown in Table 1. That is, (i) was mixed by stirring and dissolved to form a D phase, and then (b), (c) and (d) were added to obtain the (W1 + W2) / O type emulsion composition of Example 1.

<2> Observation of Emulsion The (W1 + W2) / O type emulsion composition of Example 1 was observed with a confocal laser scanning microscope (LSM). The measurement was performed using an LSM apparatus manufactured by Carl Zeiss Microscopy Co., Ltd. at room temperature and a magnification of 400 times.
FIG. 1 shows an LSM observation image. Each color of the fluorescent probe contained in each of the water phases W1 and W2 is clearly visible, and the (W1 + W2) / O type emulsion composition of the present invention has a stable composition without the two water phases being united. It was found that it was in a state of coexisting with things.

<3> Evaluation of stability over time
A (W1 + W2) / O type emulsified composition of the present invention was prepared via D-phase emulsification in the same manner as in Example 1 with the formulation shown in Table 2 (Example 2).
For comparison, a (W1 + W2) / O type emulsion composition was prepared by the method disclosed in Patent Document 2 with the formulation shown in Table 3. That is, W is added to Ho and stirred and mixed to obtain a W1 / O type emulsion composition, and G is added thereto and stirred and mixed to obtain the (W1 + W2) / O type emulsion composition of Comparative Example 1. It was.
In addition, the prescription of Table 2 and Table 3 is the same component and the same compounding quantity.

The (W1 + W2) / O type emulsion compositions of Example 2 and Comparative Example 1 prepared as described above were stored at 5, 20, 40, or 50 ° C. for 2 weeks or 1 month, respectively, and then placed at room temperature for 12 hours. Thus, the emulsion image was observed with a confocal laser microscope using the fluorescent probe in the aqueous phase as a marker. The results are shown in Table 4.
As shown in Table 4, the emulsion composition of the present invention can stably maintain a coexisting state in the composition without the two aqueous phases being united even when stored under high temperature conditions. did it. This is presumably because the emulsified composition of the present invention has an aqueous phase covered with a highly elastic D phase film by D phase emulsification.

  According to the present invention, a water-in-oil emulsion composition having improved stability over time is provided. In particular, a (W1 + W2) / O type emulsion composition that is stable over time even under high-temperature conditions is provided, and two aqueous phases having different compositions may exist stably without being united in the composition. it can.

Claims (7)

  A water-in-oil emulsion composition in which an aqueous phase is covered with a D-phase film.   A water-in-oil emulsion composition in which an emulsion is formed by D-phase emulsification.   The oil according to claim 1, comprising at least one selected from polyhydric alcohol fatty acid esters, silicone surfactants, cationic surfactants, amphoteric surfactants, and anionic surfactants. Water-type emulsion composition.   The water-in-oil emulsion composition according to any one of claims 1 to 3, comprising a polyhydric alcohol. The water-in-oil emulsion composition according to any one of claims 1 to 4, comprising two or more aqueous phases having different compositions.   The water-in-oil emulsion composition according to any one of claims 1 to 5, which is a skin external preparation.   The water-in-oil emulsion composition according to claim 6, which is a cosmetic.