JPH08126832A - Water-in-oil type emulsion - Google Patents

Abstract

PURPOSE: To prepare a water-in-oil type emulsion containing amino acids and their salts, having an excellent dermatologic action on the skin, and excellent in stability and usability. CONSTITUTION: This water-in-oil type emulsion contains (A) a water-in-oil type emulsion composition composed (a) a material which is liquid at ordinary temp., and selected from a group of a partial ester of a polyhydric alcohol having at least >=3 hydroxyl groups in the molecule and a fatty acid and the one obtained by adding 1-10mol ethylene oxide to a hydroxyl fatty triglyceride, and (b) an aq. solution containing >=0.1% one or more kinds of amino acids and/or their salts and having 1:1 to 1:46 weight ratio of (b) to (a) and (B) 0.1-10% organic modified clay mineral.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-in-oil emulsion which contains an amino acid having an excellent effect on the skin and salts thereof and is excellent in stability and usability.

[0002]

2. Description of the Related Art Conventionally, since amino acids and / or salts thereof have excellent effects on the skin, it has been desired to blend them into cosmetics. There is JP-A-53-21393 "water-in-oil type emulsifier composition". This technique is carried out at room temperature selected from the group consisting of (i) partial ester of polyhydric alcohol having at least 3 or more hydroxyl groups in the molecule and fatty acid, and hydroxy fatty acid triglyceride to which 1 to 10 mol of ethylene oxide is added. A liquid substance and (ii) an aqueous solution containing 0.1% or more of one or more amino acids and / or salts thereof, and (i) pair (i
The present invention relates to a water-in-oil emulsifier composition, wherein the weight ratio of i) is 1: 1 to 1:46.

[0003]

However, the water-in-oil emulsion using this emulsifier composition may cause oil floating at high temperatures, and further improvement in stability has been desired. The present invention solves the problems of the prior art and provides a water-in-oil emulsion that contains an amino acid and / or a salt thereof having an excellent action on the skin and is excellent in stability and usability. The purpose is to do.

[0004]

As a factor for destabilizing the water-in-oil emulsion obtained by the above-mentioned conventional technique at high temperature, it is considered that the water-in-oil emulsion cannot be sufficiently stabilized only by the emulsifier composition. Therefore, the present inventors can improve the stability of a water-in-oil emulsion by combining an organically modified clay mineral for improving the stability of the emulsifier composition, and also greatly improve the usability. did it. That is, the present invention is selected from the group consisting of (A) (a) a partial ester of a polyhydric alcohol having at least 3 or more hydroxyl groups in the molecule and a fatty acid, and 1 to 10 mol of ethylene oxide added to hydroxy fatty acid triglyceride. With substances that are liquid at room temperature
(b) An aqueous solution containing one or more amino acids and / or salts thereof in an amount of 0.1% or more.
(b) a water-in-oil type emulsifier composition having a weight ratio of 1: 1 to 1:46, and (B) an organically modified clay mineral 0.1-10.
It is a water-in-oil emulsion characterized by containing 0%.

Next, the structure of the present invention will be described in detail. In the present invention, it is important that the fatty acid partial esters of polyhydric alcohol used in the water-in-oil emulsifier composition (A) are liquid at room temperature. This is because substances that are solid at room temperature, such as glycerol monostearate and sorbitan monostearate, do not separate into two layers and form an effective gel even when mixed with an aqueous amino acid solution.

The fatty acid partial ester of polyhydric alcohol which is liquid at room temperature can be derived from the following substances. The polyhydric alcohols used have 3 or more hydroxyl groups and are glycerin, diglycerin, triglycerin, tetraglycerin, pentaglycerin, hexaglycerin,
Octaglycerin, nonaglycerin, decaglycerin,
Trimethylolethane, trimethylolpropane, pentaerythritol, sorbitan, sorbitol and the like.
Fatty acids that react with these polyhydric alcohols to form partial esters are selected from caprylic acid, capric acid, oleic acid, linoleic acid, ricinoleic acid, isooctanoic acid, isomyristic acid, isopalmitic acid, and isostearic acid. obtain.

[0007] These partial esters generally refer to monoesters, diesters, triesters and some tetraesters, pentaesters, etc., individually or as a mixture thereof. When a mixture is used, the preferable mixing ratio depends on the type of carboxylic acid and the number of hydroxyl groups of the polyhydric alcohol. For example, in a glycerol ester having three hydroxyl groups, those having a fatty acid having 8 carbon atoms mainly consisting of a mixture of diesters and triesters and those having 18 carbon atoms mainly consisting of a mixture of monoesters and diesters are preferable. Further, in fatty acids having 18 carbon atoms, esters having different hydroxyl groups, for example, glycerol or trimethylolpropane having 3 hydroxyl groups are mainly a mixture of mono and diesters, and diglycerol having 4 hydroxyl groups are mainly mono and diesters. Mixtures of some triesters are also preferred, which in the case of sorbitol with 6 hydroxyl groups mainly consist of diesters, triesters and some tetraesters. That is,
As the number of hydroxyl groups in the polyhydroxyl compound increases, the content of triester or tetraester gradually increases.

Of these partial esters, particularly preferable ones are glycerin mono-2-heptyl undecanoate, trimethylolpropane mono-2-heptyl undecanoate, diglycerin di-2-heptyl undecanoate, glycerin mono-9. -Methylheptadecanoate, trimethylolpropane mono-9-methylheptadecanoate, diglycerin di-9-methylheptadecanoate, pentaerythritol di9-methylheptadecanoate, glycerin monooleate, trimethylolpropane monooleate , Diglycerin diolate, glycerin diricinolate, sorbitan mono (di) oleate, sorbitan di (tri) oleate and the like.

Next, an ethylene oxide adduct of hydroxy fatty acid triglyceride is also a compound involved in the present invention. Hydroxy fatty acid triglyceride ethylene oxide adducts include ethylene oxide adducts of castor oil or hydrogenated castor oil, with a blend of at least about 1 mole to about 10 moles of ethylene oxide adduct being preferred.

As the substance which forms a water-in-oil type emulsifier composition in the presence of an amino acid or a salt thereof, the above-mentioned partial ester of a polyhydric alcohol having at least 3 or more hydroxyl groups and a fatty acid, and hydroxy. In addition to ethylene oxide adduct of fatty acid triglyceride,
Partial ester of polyhydric alcohol and fatty acid with 1 to 10 mol of ethylene oxide added, or partial ester of polyhydric alcohol with 1 to 10 mol of ethylene oxide and fatty acid, also selected from those which are liquid at room temperature Can be done. Specific examples of the former include ethylene oxide 1 to 1 such as glycerin di-2-heptyl undecanoate, glycerin-diolate, sorbitan di-2-heptyl undecanoate, sorbitan diolate.
An example is a 0 mol adduct. Specific examples of the latter include glycerin or sorbitol, ethylene oxide 1-
A compound obtained by partially esterifying 2-heptylundecanoic acid or oleic acid can be mentioned as the compound added with 10 mol.
Both are the same as the substance (A) (a) in the present invention,
Mix with an aqueous solution of an amino acid or its salt to form a water-in-oil emulsifier composition.

Next, in the present invention, the amino acids or salts thereof used in the water-in-oil emulsifier composition (A) are the following general food additives, amino acids known as non-pharmaceutical drugs or It may be selected from the salts. L-amino acid; L-alanine, β-alanine, L-arginine hydrochloride, L-asparagine monohydrate, L-aspartic acid, L-citrulline, L-glutamic acid, L-glutamic acid hydrochloride, L-glutamine, glycine , L-histidine, L-histidine hydrochloride monohydrate, L-hydroxyproline, L-isoleucine, L-leucine, L-lysine, L-lysine hydrochloride, L-ornithine hydrochloride, L-proline, L- Phenylalanine, L-serine, L-threonine, L-tryptophan, L-tyrosine, L-valine, L-doper and L-α aminobutyric acid. Of course, the same applies to the D isomer and DL isomer as isomers. Among these, particularly preferred are glycine,
It is an aqueous solution having an appropriate concentration of L-hydroxyproline, L-alanine, β-alanine, L-proline, and L-serine. Next, as the metal salt of the amino acid, there are monovalent metal salts, that is, sodium, potassium and lithium salts, and divalent metal salt calcium and magnesium salts. Among these, particularly preferable ones are sodium L-aspartate monohydrate, potassium L-aspartate dihydrate, L
-Sodium glutamate monohydrate, L-potassium glutamate monohydrate in appropriate concentration.

Water-in-oil type emulsifier composition (A) in the present invention
Is an aqueous solution of amino acids or salts thereof at various concentrations,
It is obtained by simply mixing the fatty acid partial esters of polyhydric alcohols or the ethylene oxide adducts of hydroxy fatty acid triglycerides in the appropriate proportions and continuing stirring until a water-in-oil gel is formed.

In the present invention, an aqueous solution of an amino acid or a salt thereof is added to a fatty acid partial ester of a polyhydric alcohol or an ethylene oxide adduct of hydroxycarboxylic acid triglyceride while gradually stirring to obtain an emulsion having a desired hardness or viscosity. It is desirable to continue the addition and stirring until a gel is obtained. At this time, it is a feature of the present invention that all the operations can be completed at room temperature. This is because the amino acid or its salt can be encapsulated in a water-insoluble complex without being decomposed or condensed by heating.

Although the amino acids or salts thereof have different solubilities in water, it is necessary to use an aqueous solution of 0.1% or more in the water-in-oil emulsifier composition of the present invention. If it does not reach this concentration, the resulting composition is not fluid or long-term stability cannot be expected. Furthermore, the preferred state of obtaining the object of the present invention is that the amino acid or its salt is well soluble in water. Therefore, a highly concentrated aqueous solution gives a more reliable and somewhat transparent and stable water-in-oil emulsion. However, in a supersaturated aqueous solution, amino acid crystal precipitation occurs, which is not practical. For example, regarding L-sodium glutamate monohydrate, which is mentioned as one of the most preferable ones in the present invention, the desired water-in-oil content is obtained by adding an aqueous solution containing a concentration of 5% to 40%. A type emulsion can be obtained. A high concentration of 40% or more is not practical, and a low concentration of less than 5% gives a water-in-oil emulsion having fluidity.

Further, the water-in-oil emulsion (A) according to the present invention
The ratio of (a) fatty acid partial ester mixture of polyhydric alcohol and / or ethylene oxide adduct of hydroxy fatty acid triglyceride to (b) aqueous solution of amino acid and / or its salt is appropriately adjusted depending on the concentration of the aqueous solution. Exists. For example, the L-
In the case of 5% aqueous solution of sodium glutamate monohydrate, the compounding ratio of (a) to (b) is 1: 1 to 1:22 by weight,
It is preferably in the range of 1: 2 to 1:10, and in the case of a 40% aqueous solution, the mixing ratio of (a) to (b) is 1: 1 to 1: 1 by weight.
The desired product can be obtained in the range of 46, preferably 1: 2 to 1:15.

The excess amount of the aqueous solution of the amino acid or its salt added to the inner phase of the water-in-oil type emulsifier composition (A) destroys the gel structure. The compounding ratio of (a) to (b) also varies within a certain range depending on the solubility of each of the other amino acids or salts thereof, but is 1: 1 to 1:46, and the preferable ratio is: The weight ratio is in the range of 1: 2 to 1:15. Here, particularly preferable combinations include glycine, β-alanine, L-hydroxyproline, L-proline, L-serine, sodium L-aspartate monohydrate, and potassium L-aspartate dihydrate. , L-sodium glutamate monohydrate, L-
It consists of an aqueous solution of potassium glutamate monohydrate and a highly concentrated aqueous solution whose concentration is closer to supersaturation, and fatty acid partial esters of polyhydric alcohols, and the ratio of the ester mixture to the aqueous solution of amino acids or their salts is 1: 1. ˜1: 46, preferably a mixture consisting of a ratio of 1: 2 to 1:15.

In order to obtain the water-in-oil emulsion which is stable and has excellent usability by adding the water-in-oil type emulsifier composition described above, it is necessary to further add an organically modified clay mineral. The organically modified clay mineral used in the present invention is a kind of colloidal hydrous aluminum silicate having a three-layer structure and is generally represented by the following general formula 1.

[0018]

Embedded image (X, Y) _2-3 (Si, Al) ₄ O ₁₀ (OH)
₂ Z _1/3 · nH ₂ 0 However, X = Al, Fe (III), Mn (III), Cr (II
I) Y = Mg, Fe (II), Ni, Zn, Li Z = K, Na, Ca

Specifically, natural or synthetic montmorillonites such as montmorillonite, saponite, and hectorite (wherein the (OH) group in the formula is replaced with fluorine) (veegum, kunipia, laponite as commercial products) Etc.) and sodium mica known as sodium silicic mica, or synthetic mica known as sodium or lithium teniolite (commercially available Dimonite: Topy Industries Co., Ltd., etc.) and other clay minerals, and quaternary ammonium salt type cation interfaces. Obtained by treating with an activator. The quaternary ammonium salt type cationic surfactant used here is
It is represented by the following general formula 2.

[0020]

Embedded image

For example, dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, aralkyltrimethylammonium chloride, behenyltrimethylammonium chloride, myristyldimethylethylammonium chloride, cetyldimethylethylammonium chloride, stearyldimethyl. Ethyl ammonium chloride,
Aralkyldimethylethylammonium chloride, behenyldimethylethylammonium chloride, myristyldiethylmethylammonium chloride, cetyldiethylmethylammonium chloride, stearyldiethylmethylammonium chloride, aralkyldiethylmethylammonium chloride, behenyldiethylmethylammonium chloride, benzyldimethylmyristylammonium chloride, Benzyldimethylcetylammonium chloride, benzyldimethylstearylammonium chloride, benzyldimethylbehenylammonium chloride,
Benzyl methyl ethyl cetyl ammonium chloride, benzyl methyl ethyl stearyl ammonium chloride,
Dibehenyldihydroxyethylammonium chloride,
And corresponding bromide and the like, and further dipalmitylpropylethylammonium methylsulfate and the like. In carrying out the present invention, one or more of these are arbitrarily selected.

Typical organic modified clay minerals include dimethylalkylammonium hectorite, benzyldimethylstearylammonium hectorite, distearyldimethylammonium chloride treated aluminum magnesium silicate and the like. As a commercial product,
Benton 38 (montmorillonite treated with distearyl dimethyl ammonium chloride: National Red Co.) and the like. These montmorillonite type organically modified clay minerals are
It is preferable to add 0.1 to 10.0% by weight of the total amount of the water-in-oil emulsion, and more preferably 0.1 to 4.
0% by weight is compounded. If it is less than 0.1% by weight, it is difficult to obtain sufficient stability, and if it is blended up to 10.0% by weight, sufficient stability can be obtained. Not preferable.

The oil used in the water-in-oil emulsion of the present invention includes avocado oil, camellia oil, macadamia nut oil, corn oil, mink oil, as animal and vegetable oil.
Olive oil, rapeseed oil, egg yolk oil, sesame oil, wheat germ oil,
Castor oil, linseed oil, safflower oil, cottonseed oil, soybean oil,
Peanut oil, tea seed oil, rice bran oil, jojoba oil, germ oil, and the like, hydrocarbon-based oil components include liquid paraffin, ozokerite, squalene, squalane, lanolin derivatives, pristane, ceresin, vaseline, microcrystalline wax, and the like. . Further, as the esters,
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, cholesteryl 1,2-hydroxystearate, di2 -Ethylene glycol ethylhexylate, dipentaerythritol fatty acid ester, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, di-2-
Ethylhexyl trimethylolpropane, trimethylolpropane triisostearate, pentaerythritol tetra-2-ethylhexylate, glyceryl tri-2-ethylhexanoate, trimethylolpropane triisostearate, cetyl 2-ethylhexanoate, 2
-Ethylhexyl palmitate, glycerin trimyristate, tri-2-heptylundecanoic acid glyceride, castor oil fatty acid methyl ester, oleyl oleate, cetostearyl alcohol, acetoglyceride,
2-Heptylundecyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-myristic acid Hexyldecyl, 2-hexyldecyl palmitate, adipine 2-hexyldecyl, diisoprovir sebacate, ethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, triethyl citrate, triglycerin, glyceryl trioctanoate, glyceryl triisopalmitate. Etc. The blending amount of these oil components is not particularly limited, but it is an amount capable of obtaining a water-in-oil emulsion, and is a total amount of 0.
1 to 70% by weight is preferable.

[0024]

EXAMPLES Next, the present invention will be described in detail with reference to examples. However, the present invention is not limited to this. Prior to the examples, the evaluation method adopted in each example will be described.

[Evaluation Method] The prepared water-in-oil emulsion was evaluated for storage stability at 50 ° C., 37 ° C., room temperature and 0 ° C. for 1 month as follows. Appearance ◎ ……… No abnormality ○ ……… Slight oil floating in some areas △ ………… Oil floating × ………… Separation Usability (stickiness) was evaluated by a specialized panel based on the following evaluation criteria. . Sticky ◎ ………… No stickiness at all ○ ……… No stickiness △ ……… Slightly sticky × ……… Stuck

Examples 1 to 6 and Comparative Examples 1 to 4 First, water-in-oil type emulsifier compositions having the following compositions were prepared. ───────────────────────────────── (i) (ii) ─────────── ────────────────────── Purified water 50 parts 184 parts Monosodium L-glutamate 20 46 Diglyceroldiolate 5 5 ────────── ──────────────────────── * Monosodium L-glutamate is dissolved in water, and the aqueous solution is stirred and mixed with diglyceroldiolate to give an oil. A medium water type emulsifier composition is obtained. (The same applies to Examples 7 and 8 below) Next, using the obtained water-in-oil emulsifier composition, water-in-oil emulsions having the compositions shown in Table 1 were prepared and evaluated. The method for preparing the water-in-oil emulsion is as follows.
After dissolving (2), (3) and (4) at 70 ° C, (1) was added and uniformly dispersed with a homomixer, then (5) was added and further homogenized with a homomixer. , (6) are gradually added and uniformly dispersed with a homomixer, then the emulsion particles are prepared and cooled to room temperature with a heat exchanger to obtain a water-in-oil emulsion. Table 1 shows compositions and evaluation results of Examples 1 to 6 and Comparative Examples 1 to 4.
It was shown to.

[0027]

[Table 1]

Example 7 (1) Water-in-oil emulsifier composition (Note 1) 20.0% by weight (2) Liquid paraffin 30.0 (3) Beeswax 1.0 (4) Benton 27 2. 0 (5) Water 47.0 (6) Preservative Suitable amount (7) Perfume Suitable amount (Note 1) Pentaerythritol -9-Methylheptadecanoate 5.0 parts L-Glutamate sodium monohydrate 4.0 L- serine 1.0 water 40.0 (2) (3) (6) (7) to that dissolved in 70 ^O C, (4) and the mixture was uniformly dispersed by a homomixer, (1) And further homogenize with a homomixer. (5) was gradually added to this, and the mixture was uniformly dispersed with a homomixer. The emulsified particles were adjusted and cooled to room temperature with a heat exchanger to obtain a stable water-in-oil emulsion.

Example 8 (1) Water-in-oil type emulsifier composition (Note 2) 20.0% by weight (2) Liquid paraffin 30.0 (3) Beeswax 1.0 (4) Benton 27 2. 0 (5) Water 47.0 (6) Preservative proper amount (7) Perfume proper amount (Note 1) Hardened castor oil Polyoxyethylene 5 mol adduct 2.0 parts Glycine 1.6 Water 6.4 (2) (3) ) (6) (7) was dissolved in 70 ^O C, (4) was added and homogenized with a homomixer, and then (1) was added and further homogenized with a homomixer. (5) was gradually added to this, and the mixture was uniformly dispersed with a homomixer. The emulsified particles were adjusted and cooled to room temperature with a heat exchanger to obtain a stable water-in-oil emulsion.

[0030]

Industrial Applicability According to the present invention, a water-in-oil emulsion excellent in stability and usability containing an amino acid and / or a salt thereof having an excellent action on the skin can be obtained.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area A61K 7/48

Claims (2)

[Claims] 1. A selected from the group consisting of (A) (a) a partial ester of a polyhydric alcohol having at least three or more hydroxyl groups in the molecule and a fatty acid, and a hydroxy fatty acid triglyceride to which 1 to 10 mol of ethylene oxide is added. It consists of a substance that is liquid at room temperature and (b) an aqueous solution containing 0.1% or more of one or more amino acids and / or salts thereof, and the ratio of (a) to (b) is 1 by weight. A water-in-oil emulsifier composition of 1: 1 to 1:46,
(B) A water-in-oil emulsion containing 0.1 to 10.0% of an organically modified clay mineral. 2. The water-in-oil emulsion according to claim 1, wherein the water-in-oil emulsifier composition (A) and the organically modified clay mineral are used.
A water-in-oil emulsion in which the compounding ratio of (B) is in the range of 1: 0.1 to 1:10.