HK1158960B - Oil-in-water cosmetic - Google Patents

Abstract

Provided is an oil-in-water cosmetic having superior emulsion stability. The oil-in-water cosmetic comprises (a) oil droplets formed from an emulsified oily component, (b) vesicle particles for stabilizing the oil droplets, and (c) an aqueous phase containing water and a C1-4 monohydric aliphatic alcohol. Preferably the vesicle particles are formed from an amphiphilic substance that spontaneously forms vesicle particles, and are localized to the oil droplet surface. The amphiphilic substance is a polyoxyethylene-hydrogenated castor oil derivative represented by general formula (1) and preferably the average number of ethylene oxide moles added (E) is 10 to 20. (In general formula (1), E=L+M+N+X+Y+Z.)

Description

Oil-in-water type cosmetic

RELATED APPLICATIONS

The present application claims priority from japanese patent application No. 2008-308876 filed in japan on 3.12.2008, and the contents thereof are incorporated into the present application.

Technical Field

The present invention relates to an oil-in-water type cosmetic, and more particularly, to an improvement in emulsion stability of an oil-in-water type cosmetic containing a lower alcohol.

Background

Generally, when an oil-in-water type emulsification is performed using an oil component containing a functional oil, a method of emulsifying by combining both a lipophilic surfactant and a hydrophilic surfactant so as to match the HLB required for the emulsified product is generally employed. However, this method is very complicated and requires a lot of labor for selecting an optimum emulsifying agent, and in the case where a plurality of oil components are mixed together or the ratio of silicone oil or polar oil is large, the emulsion stability is poor, and it is difficult to obtain an oil-in-water type cosmetic with good stability.

In contrast, a three-phase emulsification method has been reported in which vesicle particles of an amphiphilic substance present as an independent phase in an oil/amphiphilic substance/water system are adhered to the surface of an oil-based base by van der waals force to emulsify the particles, and the three-phase emulsification method exhibits excellent stability as compared with conventional general O/W type emulsions (patent document 1).

However, the three-phase emulsification method cannot satisfy the requirement of emulsion stability.

On the other hand, lower alcohols are suitable for use in various cosmetics because they impart a refreshing feeling and a quick-drying feeling to the skin and also have the effects of astringing, cleansing, sterilizing, and promoting dryness. However, when a large amount of a lower alcohol is added to an emulsion composition such as an emulsion or cream, the use touch feeling of a refreshing feeling can be maintained, but the hardness and viscosity of the system are generally lowered, and the emulsion stability tends to be deteriorated.

Documents of the prior art

Patent document 1: japanese patent No. 3855203

Disclosure of Invention

Technical problem to be solved by the invention

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide an oil-in-water type cosmetic composition having excellent emulsion stability.

Means for solving the problems

As a result of intensive studies to achieve the above object, the present inventors have found that if a lower alcohol is used in the above three-phase emulsified oil-in-water composition, the emulsion stability is improved contrary to the conventional knowledge. For example, an amphiphilic substance that spontaneously forms vesicles is mixed with an aqueous phase containing a lower alcohol to form vesicle particles in the aqueous phase, resulting in a vesicle dispersion; then, an oily component to be emulsified is mixed with the dispersion liquid, thereby obtaining an oil-in-water type cosmetic excellent in emulsion stability.

Patent document 1 does not describe any cosmetic containing a lower alcohol and any improvement in emulsion stability by a lower alcohol.

A first subject of the present invention, namely, an oil-in-water type cosmetic comprising:

(a) oil droplet particles composed of an oily component to be emulsified;

(b) vesicle particles for stabilizing the oil droplet particles; and

(c) an aqueous phase containing water and a C1-4 monohydric aliphatic alcohol.

In the oil-in-water type cosmetic, the vesicle particles are formed by an amphiphilic substance which spontaneously forms vesicle particles, and are preferably localized on the surface of the oil droplet particles.

In the oil-in-water type cosmetic, the amphiphilic substance is a polyoxyethylene hydrogenated castor oil derivative represented by the following general formula (1), and the average addition mole number (E) of ethylene oxide is preferably 10 to 20.

In the general formula (1), E ═ L + M + N + X + Y + Z.

In the oil-in-water type cosmetic composition as described above, the alcohol is preferably contained in an amount of 5 to 50% by mass based on the total amount of the cosmetic composition.

The oil-in-water type cosmetic preparation as described above preferably contains an ultraviolet absorber. In the oil-in-water type cosmetic composition, the ultraviolet absorber is preferably one or more selected from the group consisting of octocrylene (octocrylene), octyl methoxycinnamate, 4-tert-butyl-4' -methoxydibenzoylmethane, methylenebisbenzotriazolyl tetramethylbutylphenol, bisethylhexyloxyphenol methoxyphenyl triazine, diethylamino hydroxybenzoyl hexyl benzoate, ethylhexyl triazone, phenylbenzimidazole sulfonic acid, benzalmalonate polysiloxane, diethylhexyl butamidotriazone, and 2- [4- (2-ethylhexyloxy) -2-hydroxyphenyl ] -2H-benzotriazole.

The oil-in-water type cosmetic preparation of any one of the above aspects preferably further comprises one or more selected from carboxyvinyl polymers, succinoglycans, agar, hydroxyethyl cellulose, hydroxypropyl cellulose and xanthan gum.

The second subject of the present invention, namely, a method for producing an oil-in-water type cosmetic, is characterized in that an aqueous phase containing water and ethanol is mixed with an amphiphilic substance which spontaneously forms vesicles, and vesicle particles are formed in the aqueous phase to obtain a vesicle dispersion;

mixing the oily component to be emulsified with the dispersion to obtain an oil-in-water type cosmetic.

Advantageous effects

The present invention can significantly improve the stability of an oil-in-water type cosmetic emulsified in an aqueous phase by attaching vesicle particles to oil droplet particles composed of an oily component to be emulsified, using a lower alcohol.

Drawings

FIG. 1 is a schematic diagram of the emulsification mechanism; (a) to explain the adsorption mechanism of a monomolecular film of a conventional surfactant, and (b) to explain the attachment mechanism of vesicle particles.

FIG. 2(a) is a schematic view illustrating a phenomenon caused by thermal collision in a conventional adsorbed molecule type; (b) to illustrate a phenomenon caused by thermal collision in the vesicle particle attachment type.

Fig. 3 is an optical microscope photograph of a three-phase emulsified composition without blending a lower alcohol (ethanol).

Fig. 4 is an optical microscope photograph of a three-phase emulsified composition compounded with 2% lower alcohol (ethanol).

Fig. 5 is an optical microscope photograph of a three-phase emulsified composition compounded with 15% lower alcohol (ethanol).

Detailed Description

The following describes embodiments of the present invention in detail, but the present invention is not limited thereto.

The oil-in-water type cosmetic of the present invention is a three-phase emulsion oil-in-water type composition in which an oily component to be emulsified is dispersed as oil droplet particles in an aqueous phase, and the vesicle particles are confined on the surface of the oil droplet particles. Therefore, the emulsion stability is excellent as compared with the conventional oil-in-water type composition, and the emulsion stability is also excellent as compared with the conventional three-phase emulsion oil-in-water type composition because a lower alcohol is added.

The oil-in-water type cosmetic of the present invention is preferably prepared by adding an amphiphilic substance which spontaneously forms vesicle particles to an aqueous phase containing water and a lower alcohol, mixing the mixture with a mixer such as a homogenizer (homomixer), and forming vesicle particles in the aqueous phase to obtain a vesicle dispersion; then, the oily component to be emulsified is mixed with the obtained dispersion liquid and emulsified, thereby obtaining the oil-in-water type cosmetic of the present invention. The lower alcohol may be present together with the vesicle particles at least before emulsification, or may be added after forming vesicles in an aqueous phase not containing the lower alcohol, and the oily component to be emulsified is mixed and emulsified. However, from the viewpoint of the stabilization effect, the above-mentioned form of forming vesicles in an aqueous phase to which a lower alcohol is added in advance is preferable.

In the aqueous phase used in the present invention, water-soluble components other than water and lower alcohols may be added. The water-soluble component is not particularly limited, and a water-soluble component generally used in cosmetics, pharmaceuticals, and the like may be added in addition to the water-soluble solvent within a range not affecting stability.

The amount of the aqueous phase added is not particularly limited, but is usually 20 to 90% by mass in the cosmetic.

The lower alcohol used in the present invention may be a monohydric aliphatic alcohol having 1 to 4 carbon atoms, for example, one or more selected from ethanol, methanol, propanol, isopropanol, butanol, isobutanol, etc., and ethanol is particularly preferred in view of stability.

The amount of the lower alcohol used in the present invention is not particularly limited, but is preferably 5 to 50% by mass of the total amount of the cosmetic. When the amount of the lower alcohol added is too small, a sufficient emulsion stabilizing effect may not be obtained. Further, the emulsion stabilizing effect is improved with an increase in the content of the lower alcohol, but even if it exceeds 50 mass%, the emulsion stability cannot be further improved and it is uneconomical, and the feeling of use is also poor.

As the oily component to be emulsified, any oily component which is generally used in cosmetics may be added. For example, any component selected from oils and fats, waxes, hydrocarbon oils, silicone oils, higher fatty acids, higher alcohols, synthetic oils and fats, natural oils and fats, and the like may be added, and there is no particular limitation as long as the effects of the present invention are not impaired.

The amount of the oily component to be emulsified is not particularly limited, but is usually 0.1 to 30% by mass of the total amount in the cosmetic.

Examples of the oils and fats include avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, linseed oil, peach kernel oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, japanese nutmeg oil, rice bran oil, paulownia oil, japanese tung oil, jojoba oil, germ oil, triglycerides, cacao butter, coconut oil, horse fat, hydrogenated coconut oil, palm oil, beef tallow, mutton tallow, hydrogenated beef tallow, palm kernel oil, lard, beef bone tallow, lacquer oil, hydrogenated oil, beef foot oil, jatropha wax, hydrogenated castor oil, and the like.

Examples of the waxes include beeswax, candelilla wax, cotton wax, carnauba wax, bayberry wax, chinese insect wax, spermaceti wax, montan wax, rice bran wax, lanolin, kapok wax, lanolin acetate, liquid lanolin, sugar cane wax, isopropyl lanolate, hexyl laurate, reduced lanolin, jojoba wax, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol ester, POE cholesterol ether, polyethylene glycol fatty acid ester, and POE hydrogenated lanolin alcohol ether.

Examples of the hydrocarbon oil include isohexadecane and isododecane.

Examples of the silicone oil include linear or cyclic polysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane, polymethylhydrosiloxane, decamethylpolysiloxane, dodecamethylpolysiloxane, tetramethyltetrahydrosiloxane, dimethylcyclotetrasiloxane and dimethylcyclopentasiloxane.

Examples of the higher fatty acid include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, undecylenic acid, tall oil oleic acid, isostearic acid, linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).

Examples of the higher alcohol include linear alcohols (e.g., lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, cetostearyl alcohol, etc.), branched alcohols (e.g., monostearyl glyceryl ether (batyl alcohol), 2-decyltetradecyl alcohol, lanolin alcohol, cholesterol, phytosterol, hexyldodecanol, isostearyl alcohol, octyldodecanol, etc.), and the like.

Examples of the synthetic oils and fats include isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, cholesterol 12-hydroxystearate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid ester, N-alkyldiol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, di-2-heptylundecyl glyceride, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisomethylpropyl stearate, pentaerythrityl tetra-2-ethylhexanoate, erythritol tetra-2-ethylhexanoate, and mixtures thereof, Glycerol tri-2-ethylhexanoate, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glycerol trimyristate, glycerol tri-2-heptylundecanoate, methyl ricinoleate, oleyl oleate, cetostearyl alcohol, glycerol acetylate, 2-heptylundecyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamate-2-octyldodecyl adipate, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, ethyl acetate, isopropyl myristate, isopropyl palmitate, and the like, Butyl acetate, ammonium acetate, triethyl citrate.

Examples of the natural oils and fats include avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, linseed oil, persic oil, wheat germ oil, sasanqua oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, japanese nutmeg oil, rice bran oil, paulownia oil, jojoba oil, germ oil, triglycerides, tricaprylin, and triisopalmitin.

When grease is used, the IOB value is preferably 0.1 to 0.6. An oil or fat having an IOB value of less than 0.1 is not refreshing in use feel, and may feel sticky. On the other hand, an oil or fat having an IOB value exceeding 0.6 is easily soluble in water, cannot function as an oil component, and may have poor emulsion stability.

The organic conceptual diagram is obtained by describing an organic conceptual diagram in which the IOB value is defined, and the root cause of all organic compounds is methane (CH)₄) All other compounds are considered to be derivatives of methane, and the number of carbon atoms, substituents, modified portions, rings, and the like are respectively set to a predetermined numerical value, and the total of the numerical values is obtained to find an organic value and an inorganic value, and the organic value and the inorganic value are plotted on a graph having the organic value as an X axis and the inorganic value as a Y axis. The organic concept is shown in "organic concept-basis and application" (Ha Tian Ming Sheng, Sanchu Shu, 1984) and so on. The IOB value in the organic conceptual diagram is a ratio of an Inorganic Value (IV) to an Organic Value (OV) in the organic conceptual diagram, i.e., "Inorganic Value (IV)/Organic Value (OV)".

The fat or oil having an IOB value of 0.1 to 0.6 is not particularly limited, and may be, for example, a compound represented by the following formula: isopropyl myristate (IOB ═ 0.18), isodecyl isononanoate (IOB ═ 0.19), octyldodecanol pivalate (IOB ═ 0.13), isostearyl pivalate (IOB ═ 0.14), isopropyl palmitate (IOB ═ 0.16), hexyl laurate (IOB ═ 0.17), hexyldecanol ethylhexanoate (IOB ═ 0.13), isotridecanol isononanoate (IOB ═ 0.16), isopropyl isostearate (IOB ═ 0.15), ethyl isostearate (IOB ═ 0.15), ethylhexyl palmitate (IOB ═ 0.13), octyldodecanol neodecanoate (IOB ═ 0.11), polyglycerol-2 tetraisostearate (IOB ═ 0.17), pentaerythrityl tetraisostearate (IOB ═ 0.15), isocetyl myristate (IOB ═ 0.10), trimethylolpropane tris (IOB ═ 0.32), trimethylolpropane tris (IOB ═ 33), trimethylolpropane tris (IOB ═ 0.16), trimethylolpropane tris (IOB ═ 0.32), trimethylolpropane tris (IOB ═ 33) Pentaerythritol tetrakis (2-ethylhexanoate) (IOB ═ 0.35), diisopropyl adipate (IOB ═ 0.46), diisostearyl malate (IOB ═ 0.28), neopentyl glycol dicaprate (IOB ═ 0.25), tripropylene glycol dineopentanoate (IOB ═ 0.52), isodecyl benzoate (IOB ═ 0.23), propylene glycol dicaprylate (IOB ═ 0.32), isononyl isononanoate (IOB ═ 0.2), ethylhexyl isononanoate (IOB ═ 0.2), isodecyl neopentanoate (IOB ═ 0.22), cetearyl octanoate (IOB ═ 0.2), cetyl hexanoate (IOB ═ 0.13), triethylhexanoate (IOB ═ 0.36), diethylhexyl succinate (IOB ═ 0.32), and the like.

Further, as the oil component, a so-called "water-retentive oil component" which has excellent solubility in water and can absorb (retain) a large amount of water can be added. The water-retentive oil component imparts moisture retention and skin-moisturizing properties, and also shows a water-retaining feeling without stickiness upon water retention.

The water-retentive oil component is an oil component having a property of retaining water, and particularly preferably has a water-retentive capacity of 100% or more, that is, an oil component capable of retaining water at least its own weight.

Examples of the water-retentive oil component include esters such as propylene glycol monoalkyl ester, dipropylene glycol monoalkyl ester, trimethylolpropane dialkyl ester, erythritol trialkyl ester, and tetraglycerol pentaalkyl ester, and specifically include amino acid ester oils such as dioctyldodecanol lauroyl glutamate, N-lauroyl-L-glutamic acid bis (cholesteryl docosyl octyldodecyl), N-lauroyl-L-glutamic acid bis (phytosterol behenyl octyldodecyl), and N-lauroyl-L-glutamic acid bis (phytosterol 2-octyldodecyl) ester; pentaerythritol benzoate oils such as pentaerythritol tetrakis (behenate/benzoic acid/ethylhexanoate); glycerin fatty acid ester oil such as diisostearin and triisocaprylic acid glyceride; carboxylate oils such as diethylhexyl succinate, diisopropyl sebacate, tripropylene glycol trimethylacetate and the like; polyhydric alcohol fatty acid esters such as castor oil and beef tallow resin; and dipentaerythritol fatty acid esters such as hexaglycerin fatty acid ester, decaglycerin fatty acid ester, and oligo-polyester of glyceryl (adipate 2-ethylhexanoate stearate), (12-hydroxystearic acid stearic acid rosin acid) dipentaerythritol ester, and (12-hydroxystearic acid isostearic acid) dipentaerythritol ester.

Examples of the other water-retentive oil component include cholesterol derivatives and phytosterol derivatives such as cholesterol, cholestanol, dehydrocholesterol, cholesteryl lanolate, cholesteryl isostearate, cholesteryl hydroxystearate, cholesteryl ricinoleate and cholesteryl macadamia oil fatty acid ester; lanolin derivatives such as lanolin, adsorption-purified lanolin, liquid lanolin, reduced lanolin, lanolin acetate, lanolin alcohol, hydrogenated lanolin alcohol, and lanolin fatty acid, and compounds obtained by modifying these with a polyether.

In particular, the water-retentive oil component preferably contains at least one member selected from the group consisting of an amino acid ester, pentaerythritol benzoate, a glycerin fatty acid ester, and a carboxylic acid ester. More preferably, the water-retentive oil component contains at least one member selected from the group consisting of pentaerythritol tetrakis (behenate/benzoic acid/ethylhexanoate), glycerol diisostearate, and N-lauroyl-L-glutamate bis (phytosterol 2-octyldodecyl).

The form of the water-retentive oil component is not particularly limited, and any one of a liquid form (e.g., glyceryl diisostearate) and a semisolid form (e.g., N-lauroyl-L-glutamic acid di (phytosterol 2-octyldodecyl) and the like) at room temperature may be used, or oil components of different forms may be used in combination.

As the vesicle-forming amphiphilic substance of the present invention, for example, a derivative of polyoxyethylene hydrogenated castor oil; or a halogen salt, a phospholipid or a phospholipid derivative of a dialkylamine derivative, a trialkylamine derivative, a tetraalkylamine derivative, a dialkenylamine derivative, a trienylamine derivative or a tetraalkenylamine derivative. Among these, a derivative of polyoxyethylene hydrogenated castor oil represented by the following general formula (1) is more preferable.

In the general formula (1), E ═ L + M + N + X + Y + Z.

As the polyoxyethylene hydrogenated castor oil derivative, a derivative having an average addition mole number (E) of Ethylene Oxide (EO) of 10 to 20 can be used. When the average addition mole number of EO is less than 10, vesicle particles are not spontaneously formed in the aqueous phase, and therefore the oil-in-water type cosmetic of the present invention cannot be obtained. When the amount is more than 20, sufficient emulsion stability cannot be achieved, and the feeling of slipperiness or the like is felt, and thus the stability and usability cannot be satisfied.

Further, two or more of the polyoxyethylene hydrogenated castor oil derivatives may be used in combination.

The amount of the amphiphilic substance added is not particularly limited, but is usually 0.1 to 10% by mass of the total amount in the cosmetic.

In the present invention, one or more kinds of tackifiers, which are generally added to cosmetics, may be added. The thickener may be present in the aqueous phase during vesicle formation, or may be added after emulsification. By mixing the tackifier, the viscosity of the cosmetic can be improved, and the usability of the cosmetic is enhanced. In addition, the emulsion stability with time can be further improved. The amount of the thickener added is preferably 0.1 to 3% by mass based on the total amount of the cosmetic. If too little, the above effects cannot be fully exerted; if too much, wrinkles may occur, and the feeling of use may be deteriorated.

The thickener may be a natural or synthetic water-soluble polymer. Examples of the plant-based polymer include plant-based polymers such as gum arabic, tragacanth gum, galactan, carob gum, guar gum, karaya gum, carrageenan, pectin, quince seed (marmelo), starch (rice, corn, potato, wheat), alginate gum (brown algae extract), and agar; microbial polymers such as dextran, Succinoglycan (Succinoglycan), and pullulan; animal polymers such as collagen, casein, albumin, and gelatin; starch-based polymers such as carboxymethyl starch and methylhydroxypropyl starch; cellulose polymers such as methyl cellulose, nitrocellulose, ethyl cellulose, methylhydroxypropyl cellulose, hydroxyethyl cellulose, sodium cellulose sulfate, hydroxypropyl cellulose, sodium carboxymethyl cellulose, crystalline cellulose, and cellulose powder; alginic acid polymers such as sodium alginate and propylene glycol alginate; vinyl polymers such as polyvinyl methyl ether, carboxyvinyl polymers (CARBOPOL, etc.) and alkyl-modified carboxyvinyl polymers (PEMULEN, etc.); a polyoxyethylene polymer; polyoxyethylene polyoxypropylene copolymer-based polymers; acrylic polymers such as sodium polyacrylate, polyethylacrylate, and polyacrylamide; and inorganic water-soluble polymers such as polyethyleneimine, cationic polymer, bentonite, magnesium aluminum silicate, hectorite, and silicic anhydride.

Among these, preferable examples of the thickener include carboxyvinyl polymer, succinoglycan, agar, hydroxyethyl cellulose, hydroxypropyl cellulose, xanthan gum, and the like.

In addition, an acrylamide thickener which can impart a skin-tight feeling in addition to emulsion stability can be preferably added.

Examples of the acrylamide-based thickener include homopolymers, copolymers, crosslinked polymers, and mixtures containing one or more kinds of units selected from 2-acrylamido-2-methylpropanesulfonic acid (═ AMPS), acrylic acid, and derivatives thereof as constituent units. Specific examples include: vinylpyrrolidone/AMPS copolymer, dimethylacrylamide/AMPS copolymer, acrylamide/AMPS copolymer, crosslinked polymer of dimethylacrylamide/AMPS crosslinked with methylenebisacrylamide, mixture of polyacrylamide and sodium polyacrylate, sodium acrylate/AMPS copolymer, hydroxyethyl acrylate/AMPS copolymer, acrylamide/ammonium acrylate copolymer, acrylamide/sodium acrylate copolymer, and the like. Among them, preferred are homopolymers of AMPS, vinylpyrrolidone/AMPS copolymers, dimethylacrylamide/AMPS copolymers, sodium acrylate/AMPS copolymers, crosslinked polymers of dimethylacrylamide/AMPS crosslinked with methylenebisacrylamide, and the like. One or two or more kinds of the acrylamide-based thickener may be used.

In addition, succinoglycan, xanthan gum, acrylamide-based thickeners, and the like have salt resistance. Among them, succinoglycan has a large retention force against temperature change, a large yield value, and an excellent effect in terms of usability such as a moist feeling in use.

Succinoglycan is a polysaccharide derived from microorganisms, and more specifically, it refers to a polysaccharide derived from microorganisms, and contains, in addition to sugar units derived from galactose and glucose, units derived from succinic acid, pyruvic acid, and acetic acid as an optional component, or salts of these acids.

More specifically, succinoglycan is a water-soluble polymer represented by the following structural formula, which contains an acetic acid unit as an optional component among a 1 galactose unit, a 7 glucose unit, a 0.8 succinic acid unit, and a 1 pyruvic acid unit, and has an average molecular weight of about 600 ten thousand.

In the general formula (2), Gluc represents a glucose unit and Galac represents a galactose unit. Also, the designation in parentheses indicates the bonding pattern between the sugar units. For example, (β 1, 4) represents β 1-4 linkage.

Examples of the microorganism which is a source of the succinoglycan include bacteria belonging to the genus Pseudomonas, genus Rhizobium, genus Alcaligenes, or genus Agrobacterium. Among these bacteria, Agrobacterium tumefaciens I-736 (deposited under the Budapest treaty on 1/3 in 1988 to the Collection of microorganisms (CNCM), accession No. I-736, publicly available) belonging to the genus Agrobacterium is particularly suitable as a supply source of succinoglycan.

Succinoglycan can be produced by culturing the above microorganism in a medium. More specifically, the carbon source may be usually selected from the group consisting of glucose, sucrose, starch hydrolysate, and the like; organic nitrogen sources such as casein, caseinate, vegetable powder, yeast extract, Corn Steep Liquor (CSL); culturing the microorganism in a culture medium containing inorganic salts such as metal sulfate, phosphate and carbonate or trace elements.

Further, succinoglycan may be added directly to the oil-in-water type cosmetic, or a decomposition product of acid hydrolysis, alkaline hydrolysis, enzymatic hydrolysis, ultrasonic treatment, or the like may be used as necessary.

The oil-in-water type cosmetic of the present invention may further contain an ultraviolet absorber and an ultraviolet protector, and is preferably used in sunscreen cosmetics.

As the ultraviolet absorber, those generally used in cosmetics are preferably used. Examples thereof include benzoic acid derivative-based ultraviolet absorbers such as p-aminobenzoic acid, and anthranilic acid derivative-based ultraviolet absorbers such as methyl anthranilate; salicylic acid derivative ultraviolet absorbers such as octyl salicylate, phenyl salicylate, and trimethylcyclohexyl salicylate; dibenzoylmethane derivative ultraviolet absorbers; benzophenone derivative-based ultraviolet absorbers such as 2, 4-dihydroxybenzophenone, 2 '-dihydroxy-4-methoxybenzophenone, 2' -dihydroxy-4, 4 '-dimethoxybenzophenone, 2', 4 '-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4' -methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid and 2-hydroxy-4-methoxybenzophenone-5-sulfonate; an ultraviolet absorbing agent of a diphenyl acrylate derivative such as octocrylene; benzotriazole derivatives such as methylenebis-benzotriazolyl tetramethylbutylphenol; ultraviolet absorbers based on triazinone derivatives such as ethylhexyl triazinone; benzylidene camphor derivative ultraviolet absorbers such as 3- (4' -methylbenzylidene) -3-penten-2-one; phenyl benzimidazole derivative ultraviolet absorbers; cinnamic acid-based ultraviolet absorbers such as octyl cinnamate, ethyl-4-isopropyl cinnamate, ethyl-2, 4-diisopropyl cinnamate, methyl-2, 4-diisopropyl cinnamate, propyl p-methoxycinnamate, isopropyl p-methoxycinnamate, isoamyl p-methoxycinnamate, 2-ethoxyethyl p-methoxycinnamate, cyclohexyl p-methoxycinnamate, ethyl- α -cyano- β -phenyl cinnamate, and 2-ethylhexyl- α -cyano- β -phenyl cinnamate; benzotriazole derivative ultraviolet absorbers such as 2, 2 ' -dihydroxy-5-methylbenzotriazole, 2- (2 ' -hydroxy-5 ' -tert-octylphenyl) benzotriazole, and 2- (2 ' -hydroxy-5 ' -methylphenyl) benzotriazole; ultraviolet absorbers of benzylidene malonate derivatives such as polysiloxane-15; imidazole acrylic acid, imidazole acrylic acid ethyl ester, 2-phenyl-5-methylbenzoxazole, 2- (2 '-hydroxy-5' -methylphenyl) benzotriazole, 2- (2-hydroxy-4-isobutoxyphenyl) -2H-benzotriazole, dibenzoanthracene, o-dianisidine, Maifang (Mexoryl), and the like.

Particularly preferably, a sunscreen cosmetic having a good sunscreen effect and excellent long-term stability can be obtained by appropriately combining ultraviolet absorbers selected from octocrylene, octyl methoxycinnamate, 4-tert-butyl-4' -methoxybenzoylmethane, methylenebisbenzotriazolyl tetramethylbutylphenol, bisethylhexyloxyphenol methoxybenzotriazine, diethylamino oxybenzoyl hexyl benzoate, ethylhexyl triazone, phenylbenzimidazole sulfonic acid, benzalmalonate polysiloxane, diethylbenzylidene malonate, diethylhexylbutamido triazone, and 2- [4- (2-ethylhexyloxy) -2-hydroxyphenyl ] -2H-benzotriazole.

The amount of the ultraviolet absorber added is not particularly limited, but is usually 0.1 to 20% by mass of the total amount in the cosmetic.

Various components generally used in cosmetics, such as moisturizers, whitening agents, powders, pH adjusters, neutralizers, antioxidants, preservatives, antibacterial agents, drugs, plant extracts, perfumes, and pigments, may be added to the composition of the present invention within a range that does not impair the effects thereof.

Examples of the moisturizer include polyethylene glycol, propylene glycol, glycerin, 1, 3-butylene glycol, xylitol, sorbitol, maltitol, chondroitin sulfate, mucopolysaccharide sulfate, trichosanthes acid, atelocollagen, cholesteryl-12-hydroxystearate, sodium lactate, bile acid salts, dl-pyrrolidone carboxylate, alkylene oxide derivatives, short-chain soluble collagen, diglycerin (EO) PO adducts, rosebush extract, cyanine extract, melilot extract, proteins such as amino acids, nucleic acids, and elastin, mucopolysaccharides such as hyaluronic acid and chondroitin sulfate, and the like.

Examples of the whitening agent include salts of L-ascorbic acid and its derivatives, salts of tranexamic acid and its derivatives, salts of alkoxysalicylic acid and its derivatives, and arbutin.

Examples of the powder component include inorganic powders (e.g., talc, kaolin, mica, sericite (serilite), muscovite, phlogopite, synthetic mica, lepidolite, biotite, expanded vermiculite, magnesium carbonate, calcium carbonate, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, strontium silicate, metal tungstate, magnesium, silica, zeolite, barium sulfate, calcined calcium sulfate (calcined gypsum), calcium phosphate, fluorapatite, hydroxyapatite, ceramic powder, metal soaps (e.g., zinc myristate, calcium palmitate, and aluminum stearate), boron nitride, and the like); organic powders (for example, acrylic resin powders such as polyamide resin powder (nylon powder), polyethylene powder, and polymethyl methacrylate powder, polystyrene powder, copolymer resin powder of styrene and acrylic acid, benzoguanamine resin powder, polytetrafluoroethylene powder, cellulose powder, polymethylsilsesquioxane powder, and silicone elastomer powder); inorganic white pigments (e.g., titanium dioxide, zinc oxide, etc.); inorganic red pigments (e.g., iron oxide (iron sesquioxide Bengala)), iron titanate, and the like); inorganic brown pigments (e.g., gamma-iron oxide); inorganic yellow pigments (e.g., yellow iron oxide yellow, yellow soil, etc.); inorganic black pigments (e.g., black iron oxide, low molecular weight titanium oxide, etc.); inorganic violet pigments (e.g., mango violet, cobalt violet, etc.); inorganic green pigments (e.g., chromium oxide, chromium hydroxide, cobalt titanate, etc.); inorganic blue pigments (e.g., ultramarine blue and ultramarine blue); pearlescent pigments (e.g., mica coated with titanium oxide, bismuth oxychloride coated with titanium oxide, talc coated with titanium oxide, mica coated with colored titanium oxide, bismuth oxychloride, fish scale foil, etc.); metal powder pigments (e.g., aluminum powder, copper powder, etc.); organic pigments such as zirconium, barium or aluminum pastels (e.g., organic pigments such as red 201, red 202, red 204, red 205, red 220, red 226, red 228, red 405, orange 203, orange 204, yellow 205, yellow 401 and blue 404, organic pigments such as red 3, red 104, red 106, red 227, red 230, red 401, red 505, orange 205, yellow 4, yellow 5, yellow 202, yellow 203, green 3 and blue 1); natural pigments (e.g., chlorophyll, beta-carotene, etc.), and the like.

Further, ultraviolet protective powder such as fine titanium oxide and fine zinc oxide may be mentioned.

The powder may be subjected to hydrophobization treatment or hydrophilization treatment depending on the purpose. As the hydrophobic treatment, a conventional method for preparing a hydrophobic treatment powder commonly used in cosmetics may be used, and for example, one or two or more of higher fatty acids, surfactants (including any of anionic, cationic, and nonionic surfactants), metal soaps, fats and oils, waxes, silicones, fluorine compounds, hydrocarbons, dextrin fatty acid esters, and the like may be used. The hydrophilization treatment may be either an organic treatment or an inorganic treatment. The hydrophilization treatment is not particularly limited, and examples thereof include polyols, polysaccharides, water-soluble polymers, metal alkoxides, and water glass.

Examples of the pH adjuster include lactic acid, citric acid, sodium citrate, diglycolic acid, succinic acid, tartaric acid, dl-malic acid, potassium carbonate, sodium hydrogen carbonate, and ammonium hydrogen carbonate.

Examples of the antioxidant include ascorbic acid, α -tocopherol, dibutylhydroxytoluene, butylhydroxyanisole, and the like.

Examples of the antiseptic and antibacterial agent include paraben, phenoxyethanol, benzoic acid, salicylic acid, phenol, sorbic acid, p-chloro-m-cresol, hexachlorophene, benzalkonium chloride, chlorhexidine hydrochloride, trichlorocarbanilide, and a photosensitizer.

The oil-in-water type cosmetic of the present invention can be widely used for cosmetics, pharmaceuticals, and quasi drugs for the appearance of skin, hair, etc. The product form is also arbitrary, and can be used as a lotion, a cream, an emulsion foundation, an emulsion sunscreen cosmetic, etc., and is particularly preferably used as a sunscreen cosmetic.

Principle of

FIG. 1 is a schematic view showing a conventional emulsification method using a surfactant and a three-phase emulsification method used in the present invention.

In the conventional method of emulsification with a surfactant, as shown in fig. 1(a), since the surfactant has a hydrophilic group and a lipophilic group having different properties in the same molecule, the lipophilic group of the surfactant is compatible with oil with respect to oil particles, and the hydrophilic group is arranged in a state of being directed to the outside of the oil particles, so that the surfactant is easily fused with water and uniformly mixed in an aqueous medium to produce an O/W type emulsion.

However, in the conventional emulsification method, the surfactant is adsorbed on the oil surface to form a monomolecular emulsion film, and thus, the surface properties of the oil may be changed depending on the kind of the surfactant. As shown in fig. 2(a), the oil droplets are united together by thermal collision, and therefore the size of the oil droplets gradually increases, and the oil and the surfactant aqueous solution are gradually separated. To prevent this, it is necessary to form a microemulsion, and a case where a large amount of a surfactant is necessary arises.

Therefore, in the present invention, vesicle particles as an emulsion dispersant phase are attached to oil particles (fig. 1(b)), thereby forming a three-phase structure of aqueous phase-emulsion dispersant phase-oil phase, which does not lower the surface capacity by the compatibility, and is less likely to be united by thermal collision, thereby achieving long-term stabilization of the emulsion (fig. 2 (b)). In such a system, the stability of the emulsion can be further improved by a lower alcohol. Further, by the emulsification method (three-phase emulsification method) of the present invention, based on the above structure, it is possible to form a latex by a small amount of an emulsification dispersant.

Examples

The present invention will be described in further detail below with reference to specific examples. Also, the present invention is not limited thereto. In addition, unless otherwise specified, the amounts (%) added are mass%.

< evaluation of stability of emulsified particles caused by addition of lower alcohol >

(preparation method)

Based on the formulation of table 1, an oil-in-water type cosmetic was prepared by the method shown below.

Polyoxyethylene hydrogenated castor oil derivatives as amphiphilic substances were added to and mixed with the aqueous phase shown in table 1 below, and the mixture was treated with a homogenizer for 1 minute to prepare an aqueous phase portion containing vesicles. While the homogenizer was started, the oil component to be emulsified described in table 1, which had been uniformly mixed in advance, was slowly added to the obtained aqueous phase portion, thereby obtaining an oil-in-water type cosmetic.

(evaluation method)

The composition of each preparation example was put into a 50ml sample tube (diameter: 3cm), rotated at 45rpm for 4 hours at room temperature, and tested to determine the degree of emulsification of the emulsified composition by visually confirming whether or not oil was present. The average particle diameter of vesicle particles in the vesicle dispersion was measured by a dynamic light scattering method using a particle size distribution meter FPAR-1000 (produced by Otsuka electronics Co., Ltd.); the emulsified particle size was directly measured by observation with an optical microscope (BX 51, made by OLYMPUS).

Evaluation criteria for emulsion stability of emulsion composition

O: no oil floating was observed visually.

And (delta): a small amount of oil was visually observed to float.

X: a large amount of oil was visually observed to float.

TABLE 1

As shown in table 1, the average particle size of vesicles formed from polyoxyethylene (10) hydrogenated castor oil contained in the aqueous phase portion was not significantly different in production example 1-1 in which no ethanol was added at all, compared to production examples 1-2 to 1-5 in which ethanol was added at each content, but emulsion stability was improved with an increase in ethanol content, and it was considered that a significant improvement effect was exhibited particularly when 5 mass% or more of ethanol was added to the cosmetic.

The reason why stability is improved by blending with ethanol is not clear, but one possibility is to improve the strength of vesicle particles and adhesion to oil droplet particles by ethanol, thereby further controlling the coalescence of emulsified particles.

Further, it can be seen that the particle size of the emulsified composition becomes smaller as the amount of ethanol added increases. The optical micrographs of the oil-in-water type cosmetics obtained in preparation examples 1-1, 1-2 and 1-5 of Table 1 are shown in FIGS. 3 to 5, respectively. It can be seen from the respective optical micrographs that the emulsified particle size becomes smaller when ethanol is blended.

< study on formation of vesicular particles by average EO addition mol >

Next, in order to obtain an average number of moles of EO added, which is preferable when polyoxyethylene hydrogenated castor oil forms vesicle particles in water, polyoxyethylene hydrogenated castor oil was dispersed in an aqueous phase by a homogenizer based on the formulation shown in table 2 to prepare a dispersion, and the appearance thereof was observed.

TABLE 2

As shown in Table 2 above, when a polyoxyethylene hydrogenated castor oil having an average EO addition mole number of 7 was used (preparation example 2-1), the polyoxyethylene hydrogenated castor oil as the amphiphilic substance was not dispersed in the aqueous phase at all, and a state of floating to the upper layer was observed.

On the other hand, when EO addition mol numbers of 30, 40 and 60 were used (preparation examples 2-4 to 2-6), the appearance was translucent, and the average particle diameter was very small and 10nm or less.

Further, when a polyoxyethylene hydrogenated castor oil having 10 to 20 EO addition mol numbers is used (preparation examples 2-2 to 2-3), the appearance is white turbid to translucent, and the particle diameter is 30 to 200 nm.

< study on the stability of emulsified particles from the number of moles of EO added >

Next, in order to obtain the preferred EO addition mole number of the polyoxyethylene hydrogenated castor oil in the oil-in-water type cosmetic of the present invention, the oil-in-water type cosmetic was prepared by the same method as in the above preparation examples based on the formulation of table 3 (preparation examples 3-1 to 3-6). The emulsified particle size of the composition of each of the above preparation examples was measured, and the usability was further evaluated. Further, the emulsion stability after standing for one month from the start of the preparation and the emulsion stability by rotation which was the same as in table 1 were observed visually, respectively. The emulsified particle size was directly measured by observation with an optical microscope (BX 51, made by OLYMPUS).

Evaluation criteria for usability

O: the composition is fresh and has quick skin fusion.

And (delta): the composition had a slightly refreshing feel and a slightly sticky feel.

X: the composition was sticky and felt sticky.

The evaluation results of the respective production examples are shown in table 3.

TABLE 3

As shown in Table 3, when polyoxyethylene hydrogenated castor oil having an average number of EO molecules added of 30, 40 and 60 (preparation examples 3-3 to 3-5) was used, the emulsified particle size tended to increase, the handling properties tended to deteriorate, and further, oil floating was observed.

On the other hand, in preparation example 3-2 in which polyoxyethylene hydrogenated castor oil having an average EO molar number of addition of 20 was blended, although slight oil lifting was observed, an emulsified composition having a reduced emulsified particle size of 1 to 5 μm and excellent usability was obtained.

In addition, in preparation example 3-1 in which polyoxyethylene hydrogenated castor oil having an average EO addition mole number of 10 was blended, the emulsified particle size was reduced to 1 to 5 μm, and the skin-friendly hydrogenated castor oil had a refreshing feel and a quick feeling of application to the skin, and no oil floating was observed.

In addition, in preparation examples 3 to 6 using a combination of polyoxyethylene hydrogenated castor oil having 10 and 20 average EO addition moles, the emulsified particle size was reduced to 1 to 5 μm, and the oil-in-water type castor oil had a refreshing feeling and a quick feeling of application to the skin, and no oil floating was observed.

From the above, it is clear that the average number of moles of EO added to the polyoxyethylene hydrogenated castor oil derivative is preferably 10 to 20.

< investigation of tackifier >

Based on the formulations shown in Table 4, oil-in-water type cosmetics (test examples 4-1 to 4-7) were prepared in the same manner as in the above preparation examples, and the emulsified particle size of each composition was measured. Then, an emulsion stability test was performed in the same manner as in the case of table 1, and the degree of emulsification of the emulsion composition was judged by visually confirming whether or not the oil floated.

TABLE 4

As can be seen from table 4, when carboxyvinyl polymer, succinoglycan, hydroxyethyl cellulose, hydroxypropyl cellulose, xanthan gum were used as the thickening agent, oil floating was particularly absent and emulsion stability was good, whereas when other thickening agents were used, oil floating was noticeable.

< study of emulsification method >

TABLE 5

^*1 preparation step

Step a (three-phase emulsification method): polyoxyethylene hydrogenated castor oil was added to and mixed with the aqueous phase, and the mixture was treated with a homogenizer for 1 minute to prepare an aqueous phase portion containing vesicle particles. Starting the homogenizer while adding the oil component to be emulsified, which is mixed uniformly in advance, to the obtained water phase part to obtain oil-in-water type cosmetic.

And a step B: mixing polyoxyethylene hydrogenated castor oil with oily component to be emulsified, and slowly adding water phase part mixed uniformly in advance while starting a homogenizer to obtain oil-in-water type cosmetic.

As is apparent from Table 5, in the oil-in-water type cosmetic composition obtained by the three-phase emulsification method (step A), the emulsion stability can be improved by using a polyoxyethylene hydrogenated castor oil having an average EO molar number of 10 to 20 in combination with ethanol (preparation example 5-1vs preparation example 5-3).

On the other hand, even in the case of the preparation by the three-phase emulsification method, when polyoxyethylene hydrogenated castor oil having an average addition mole number of more than 20 is used, the emulsion stability cannot be improved even when it is used in combination with ethanol (preparation example 5-2vs preparation example 5-4).

On the other hand, when the preparation is carried out by the step B of the conventional emulsification method, although an oil-in-water type cosmetic with good emulsion stability can be obtained by using the polyoxyethylene hydrogenated castor oil with an average addition mole number of EO (for example, 60 moles) suitable for emulsification, the emulsion stability is remarkably lowered when ethanol is used in combination (preparation examples 5 to 6vs, preparation examples 5 to 8). Further, even when the average number of moles of EO added is in the range of 10 to 20, no oil-in-water type cosmetic composition having good emulsion stability can be obtained (preparation examples 5 to 5 and 5 to 7) regardless of the presence or absence of ethanol in the conventional emulsion method.

From the above results, it is found that an oil-in-water type cosmetic having excellent emulsion stability can be obtained by mixing an oily component to be emulsified in an aqueous phase formed by co-storing ethanol in a vesicle dispersion of polyoxyethylene hydrogenated castor oil having an average number of moles of EO added of 10 to 20.

Preferred examples of the cosmetic of the present invention will be described below, but these examples are not intended to limit the present invention in any way.

Formulation example 1: oil-in-water sunscreen (sun cut) emulsion

(preparation method)

Mixing (1), (17) to (18), mixing with a homogenizer, further mixing (8) to (15), and then adding (2) to (7) and (16) while starting the homogenizer.

Formulation example 2: beauty liquid

(preparation method)

After (6) was mixed with (15) at room temperature to dissolve it uniformly, the remaining aqueous component was added and stirred sufficiently to obtain phase A (aqueous phase portion). Phase A and phase B (oil phase) prepared in advance were mixed, emulsified particles were homogenized with a homogenizer, and then neutralized with a neutralizer (23).

Formulation example 3: oil-in-water emulsion foundation cream

(preparation method)

Mixing (1) - (4), (10) - (18) and (20), mixing with a homogenizer, and then adding the oil phase obtained by mixing (5) - (9) and (19) while starting the homogenizer.

Formulation example 4: sunscreen lotion

(preparation method)

The amphiphilic substance was added to and mixed with the aqueous phase, and the mixture was treated with a homogenizer for 1 minute to prepare an aqueous phase containing vesicle particles. The obtained water phase part is slowly added with the oil component to be emulsified, which is uniformly mixed in advance, while starting the homogenizer, thereby obtaining the oil-in-water type cosmetic.

The cosmetics of the above formulation examples all had a moist and refreshing feeling in use and had excellent emulsion stability.

Formulation example 5: sunscreen lotion

(preparation method)

Mixing (1), (17) and (18), mixing with a homogenizer, and then adding (2) to (7) and (16) while starting the homogenizer. Then, the target sunscreen emulsion is obtained by adding the components (8) to (15).

Formulation example 6: anti-aging beauty liquid

(preparation method)

The mixture (1) was mixed with the mixture (15) and (16) at room temperature, and the mixture was stirred with a homogenizer to prepare vesicle particles. Then, the mixture is mixed with a previously prepared phase B (oil phase part), emulsified particles are homogenized by a homogenizer, and then the rest of the water phase component is added, and finally a neutralizer (24) is added to obtain the target anti-aging cosmetic liquid.

Formulation example 7: whitening and beautifying liquid

(preparation method)

The mixture (1) was mixed with the mixture (18) and (19) at room temperature, and the mixture was stirred with a homogenizer to prepare vesicle particles. Then, the mixture is mixed with a previously prepared phase B (oil phase), emulsified particles are homogenized by a homogenizer, and after the rest of the water phase components are added, a neutralizer (25) is finally added to obtain the objective whitening cosmetic liquid.

The oil-in-water type cosmetics according to formulation examples 5 to 7 all had excellent emulsion stability and excellent usability (spreadability, skin-friendly property, no sticky feeling, and a tight feeling).

Formulation example 8: sunscreen lotion

(preparation method)

Mixing (1), (17) and (18), mixing with a homogenizer, further mixing (8) to (15), and then adding (2) to (7) and (16) while starting the homogenizer.

Formulation example 9: anti-aging beauty liquid

(preparation method)

The mixture (1) was mixed with the mixture (15) and (16) at room temperature, and the mixture was stirred with a homogenizer to prepare vesicle particles. Then, the remaining water phase component was added, and the mixture was sufficiently stirred to obtain phase a (water phase portion), phase a was mixed with previously prepared phase B (oil phase portion), the emulsified particles were homogenized with a homogenizer, and then the neutralizer (24) was added.

Formulation example 10: whitening and beautifying liquid

(preparation method)

The mixture (1) was mixed with the mixture (18) and (19) at room temperature, and the mixture was stirred with a homogenizer to prepare vesicle particles. Then, the remaining aqueous phase component was added thereto, and the mixture was sufficiently stirred to obtain phase A (aqueous phase portion). Phase A and phase B (oil phase) prepared in advance were mixed, emulsified particles were homogenized with a homogenizer, and then a neutralizer (25) was added.

The oil-in-water type cosmetics according to formulation examples 8 to 10 all had excellent usability (spreadability, skin-friendly property, no stickiness, and a tight feeling).

Formulation example 11: beauty liquid

(preparation method)

Mixing (1), (16) and (17), mixing with a homogenizer, starting the homogenizer while adding (2) - (5), (14) - (15) heated to 70 ℃ to emulsify. Further mixing (6), (8) to (13), and then neutralizing with (7).

Prescription example 12: oil-in-water sunscreen emulsion

(preparation method)

Mixing (1), (14) and (15), mixing with a homogenizer, starting the homogenizer while adding (2) - (7) and (13) heated to 70 ℃ to emulsify. Further, the above-mentioned components were mixed with the above-mentioned mixture (8) to (12).

Formulation example 13: oil-in-water emulsion foundation cream

(16) 0.2 parts of methyl p-hydroxybenzoate

(17) Proper amount of perfume

(18) Balance of purified water

(19) Ethanol 7.0

(preparation method)

Mixing (1), (18) and (19), mixing with a homogenizer, starting the homogenizer, adding (2) - (8) and (17) heated to 70 deg.C, and emulsifying. Further, the above-mentioned components were added and mixed (9) to (16).

None of the oil-in-water type cosmetics of formulation examples 11 to 13 had a sticky feeling peculiar to the oil-in-water type emulsion cosmetic containing a high polar oil, had a moist and refreshing feeling in use, and was excellent in emulsion stability.

Claims (6)

1. A three-phase emulsion oil-in-water type cosmetic characterized by comprising:

(a) oil droplet particles composed of emulsified oily components;

(b) vesicle particles for stabilizing the oil droplet particles; and

(c) an aqueous phase comprising water and ethanol;

wherein the vesicle particles are attached to the surfaces of oil drop particles as an emulsion dispersant phase of an independent phase, and the vesicle particles are polyoxyethylene hydrogenated castor oil derivatives represented by the following general formula (1) and are formed by amphiphilic substances with the average addition mole number (E) of ethylene oxide of 10-20;

in general formula (1), E = L + M + N + X + Y + Z;

the content of the ethanol is 5-50 mass% of the total amount of the cosmetics;

the three-phase emulsified oil-in-water type cosmetic is prepared by the following three-phase emulsification preparation method: mixing an aqueous phase containing water and ethanol with the amphiphilic substance to form vesicle particles in the aqueous phase, thereby obtaining a vesicle dispersion; mixing the emulsified oily component with the dispersion to obtain a three-phase emulsified oil-in-water type cosmetic.

2. The three-phase emulsified oil-in-water type cosmetic according to claim 1, wherein the amphiphilic substance spontaneously forms vesicle particles which are localized on the surface of the oil droplet particles.

3. The three-phase emulsified oil-in-water type cosmetic preparation according to claim 1 or 2, which comprises an ultraviolet absorber.

4. The three-phase emulsified oil-in-water type cosmetic composition according to claim 3, wherein the ultraviolet absorber is one or more selected from the group consisting of octocrylene, octyl methoxycinnamate, 4-tert-butyl-4' -methoxydibenzoylmethane, methylenebisbenzotriazolyl tetramethylbutylphenol, bisethylhexyloxyphenol methoxyphenyl triazine, diethylamino hydroxybenzoyl hexyl benzoate, ethylhexyl triazone, phenylbenzimidazole sulfonic acid, benzalmalonate polysiloxane, diethylhexyl butamidotriazone, and 2- [4- (2-ethylhexyloxy) -2-hydroxyphenyl ] -2H-benzotriazole.

5. The three-phase emulsified oil-in-water type cosmetic composition according to claim 1 or 2, which further comprises one or more selected from the group consisting of carboxyvinyl polymer, succinoglycan, agar, hydroxyethyl cellulose, hydroxypropyl cellulose and xanthan gum.

6. A method for producing a three-phase emulsion oil-in-water type cosmetic, characterized by mixing an aqueous phase containing water and ethanol with the amphiphilic substance according to claim 1 which is spontaneously formed, and forming vesicle particles in the aqueous phase to obtain a vesicle dispersion; mixing the emulsified oily component with the dispersion to obtain an oil-in-water type cosmetic; the content of the ethanol is 5-50% by mass of the total amount of the cosmetic.