JPH0669532B2 - Oil-in-water emulsion composition - Google Patents

Description

The present invention relates to an oil-in-water emulsion composition, and more particularly, a weak aliphatic phosphate ester salt, a hydrogenated natural phospholipid, and a humectant. It relates to an acidic oil-in-water emulsion composition.

[Conventional technology and its problems]

Recently, skin cosmetics have a pH range of skin of about dermatology.
It is said that it is desirable to make it weakly acidic in accordance with the fact that it is 5.0 to 6.0, and there is a tendency that the number of weakly acidic emulsion cosmetics increases.
In addition, as a function of emulsified cosmetics, the moisturizing effect on the skin has come to be emphasized, and in recent years, those with a strong stickiness in use have been shunned by consumers, and the sticky feeling remains moist for a long time. Those who do tend to be preferred.

Conventionally, for the purpose of obtaining such emulsified cosmetics, ethylene oxide addition-type nonionic surfactants, alkyl sulfates, N-acylated glutamate and the like as weakly acidic emulsifiers, and glycerin and sorbitol as moisturizers,
Polyhydric alcohols such as propylene glycol, amino acids such as pyrrolidone carboxylate, serine, glutamic acid, etc. have been used.

[Problems to be solved by the invention]

However, emulsion-type cosmetics such as creams and emulsions containing these emulsifiers and moisturizers have stickiness and squeaky feeling on the skin, and the moisturizing effect and moisturizing sensation are poor, and they are not sufficiently satisfactory. It was

[Means for solving problems]

The present inventors have conducted extensive studies to solve the above problems, and as a result, by using a combination of a higher aliphatic phosphate ester salt, a hydrogenated natural phospholipid and a humectant, excellent use is achieved. The present invention has been completed by finding that an emulsion type cosmetic having a feeling and high moisturizing performance and capable of maintaining the moisturizing effect for a long time can be obtained.

That is, the present invention provides a weakly acidic oil-in-water emulsion composition containing a higher aliphatic phosphate ester salt, a hydrogenated natural phospholipid, and a humectant.

Examples of the higher aliphatic phosphate ester salt used in the present invention include the following general formula (I), (In the formula, R ₁ is an alkyl or alkenyl group having 12 to 22 carbon atoms, X ₁ and X ₂ are the same or different, and are substituted with a hydrogen atom, an alkali metal, ammonium, or an alkyl group having 1 to 5 carbon atoms. A counter ion selected from the group consisting of ammonium, an alkanolamine having a hydroxyalkyl group having 2 to 3 carbon atoms and a basic amino acid, provided that X ₁ and X ₂ are present.
In which both are hydrogen atoms), and examples thereof include linear alkyl phosphates such as monolauryl phosphate and monocetyl phosphate, alkenyl phosphates such as monooleyl phosphate, and isostearyl acid. Preferred are salts of branched alkyl phosphates such as, among others, linear alkyl phosphates having 12 to 18 carbon atoms are particularly preferred.

The higher aliphatic phosphate ester salt is obtained by appropriately neutralizing the corresponding higher aliphatic phosphate ester with a basic substance so that the pH of the target oil-in-water emulsion composition falls within a desired weakly acidic range. used. Examples of the basic substance used for this purpose include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; basic amino acids such as arginine, ornithine, lysine and oxylysine; triethanolamine, diethanolamine and triisopropanolamine. Alkanolamines having a hydroxyalkyl group having 2 to 3 carbon atoms such as; ammonium substituted with an alkyl group having 1 to 5 carbon atoms such as ammonium hydroxide and tetramethylammonium hydroxide, and the like, particularly basic amino acids preferable.

Neutralization of higher aliphatic phosphate with basic substances
Either a method separately performed in series before adding the phosphate ester to the system or a method performed by individually adding the phosphate ester and a basic substance to the system and performing them in the system can be used.
It is particularly preferable to carry out in-system. The neutralization does not necessarily have to be complete neutralization, but may be partial neutralization, and the basic substance may be used in excess of the neutralization amount or more. That is, the amount of the basic substance may be appropriately selected so that the pH of the target oil-in-water emulsion composition falls within the weakly acidic range. The amount of the basic substance is generally 0.2 mol to 1.8 mol, preferably 0.4 to 1.5 mol, per 1 mol of the higher aliphatic phosphate ester.

Examples of the hydrogenated natural phospholipid include soybean phospholipid and egg yolk phospholipid, and soybean phospholipid is particularly preferable. The hydrogenation rate of the phospholipid can be determined, for example, by measuring the iodine value fatty acid composition. In the present invention, those having an iodine value of 0 to 60 are preferable, and those having an iodine value of 10 or less are particularly preferable. The proportion of the neutral substance (mainly triglyceride) contained in the phospholipid is preferably 40% by weight (hereinafter referred to as%) or less, and particularly preferably 10% or less. The hydrogenated phospholipid used in the present invention is a mixture of phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and the like, and the content of phosphatidylcholine as the main component is preferably 15% or more.

The higher aliphatic phosphate ester salt is preferably added to the oil-in-water emulsion composition of the present invention in an amount of 0.01 to 5.00%, particularly 0.05 to 3.00%. The hydrogenated natural phospholipid is preferably added in an amount of 0.1 to 10%, particularly 0.3 to 5%.

As the moisturizer, for example, propylene glycol,
Examples thereof include polyhydric alcohols such as glycerin, polyglycerin, polyethylene glycol and sorbitol, and amino acids such as pyrrolidone carboxylate, serine and glutamate, which may be used alone or in combination. A moisturizer is added to the oil-in-water emulsion composition of the present invention in an amount of 0.1 to 20.
%, Especially 0.5 to 15%.

The oil-in-water emulsion composition of the present invention comprises, for example, a higher aliphatic phosphate ester salt, a hydrogenated natural phospholipid and a humectant, which are dissolved in oil or water, and then mixed with an oil phase and an aqueous phase to emulsify the mixture. It is prepared by soaking.

Examples of oils include waxes such as beeswax, lanolin, carnauba wax, and candelilla wax; triglycerides such as castor oil and olive oil; hydrocarbons such as ceresin, liquid paraffin, vaseline, squalane, etc .; fatty acids such as stearic acid, palmitic acid; cetanol. , Higher alcohols such as stearyl alcohol; ester oils such as cetyl 2-ethylhexanoate and octyldodecyl myristate, and the like, which are generally used as a base material for cosmetics are blended. The blending amount of oil can be arbitrarily selected, but it is preferably set to 1 to 70%. The amount of water is 20
It is preferable to set it to ˜90%.

In the oil-in-water emulsion composition of the present invention, if necessary,
Known components for cosmetics such as nonionic surfactants, thickeners, fragrances, preservatives, dyes and pigments can be added.

As the nonionic surfactant, either a hydrophilic or lipophilic one can be used, and 0.5 or more of the higher aliphatic phosphate ester salt can be used.
It is preferable to mix them in an amount of about 1.0 times by weight.

Examples of the thickener include carboxyvinyl polymer, polyvinylpyrrolidone, carboxymethyl cellulose, montmorillonite and the like.

The oil-in-water emulsion composition of the present invention can be in various forms such as vanishing cream, emulsion, cold cream, cleansing cream, hair cream, foundation cream and hand cream.

〔The invention's effect〕

The oil-in-water emulsion composition of the present invention is a combination of a higher aliphatic phosphate ester salt, a hydrogenated natural phospholipid and a moisturizing agent, and thus has an excellent feeling on the skin and is not sticky. It is less likely to occur, has a particularly high moisturizing effect, and has the characteristic that the moisturizing effect can be maintained for a long time.

〔Example〕

Next, examples will be described. In the examples,
The moisturizing effect and the dynamic friction coefficient were measured under the following conditions.

(Measurement conditions for moisturizing effect) 25 ℃, 50% RH Measurement site: Frontal flexion of the forearm Application amount: 50mg / cm ² Measuring device: High frequency impedance meter (IBS Mod
el IB-354) (Conditions for measuring the dynamic friction coefficient) 25 ° C, 50% RH Applicable amount: 10 μl applied to the contact Measuring device: Surface friction tester (Kato, KES-F4) Fixed plate (contact surface) Acrylic contact Piglet skin (0.25 cm ² ) Moving distance 2 cm (F: Frictional force, P: Friction static load) Static load 25 g Movement rate 1 mm / sec Example 1 An oil-in-water emulsion composition having the composition shown in Table 1 below was prepared by the following method, and its emulsified particles were used. The average particle size, pH, appearance immediately after production, viscosity immediately after production, storage stability after 1 month at 40 ° C., and usability by a specialized panelist were sensory examined. Furthermore, it is known that the conductance of the skin surface increases with an increase in the water content of the skin surface (stratum corneum) [for example, the Japanese Society of Dermatology, Vol. 90, No. 5, 445-447]. (1980)], the moisturizing effect was investigated by measuring the conductance of the skin surface.
Furthermore, the dynamic friction coefficient (μ) was measured as a physical quantity corresponding to the stickiness sensory evaluated by a specialized panelist.

(Manufacturing method) The oil phase is heated to 70 to 80 ° C, melted by stirring, and the water phase heated and dissolved at 70 to 80 ° C is added to the mixture under stirring to emulsify it, and after cooling to 50 ° C, add a flavor , Cool to 20-30 ℃.

The results are shown in Table 2, FIG. 1 and FIG.

Results: As shown in Table 2, the oil-in-water emulsion composition of the present invention has a long-lasting appearance, stability, familiarity to the skin, less stickiness, and longer lasting moist feeling than the comparative product. Was excellent at. Further, the product of the present invention has a smaller change in conductance over time than the comparative product, can maintain a high value for a long time (Fig. 1), has an excellent moisturizing effect, and has a dynamic friction coefficient higher than that of the comparative product. Because it is extremely small (Fig. 2),
It became clear that it was a sticky one.

Example 2 Soybean phospholipids having different iodine values were used as hydrogenated natural phospholipids to prepare an oil-in-water emulsion composition having the composition shown in Table 3, and its performance was examined in the same manner as in Examples.
The physical properties such as iodine value of the soybean phospholipid used are 4th.
Shown in the table.

The results are shown in Table 5.

As shown in Table 5, among the hydrogenated natural phospholipids, the partially hydrogenated products having an iodine value of more than 60 have good skin compatibility and moisturizing feel, but have a drawback of bad smell.

Example 3 An oil-in-water emulsion composition (cream) having the composition shown in Table 6 below was prepared and its performance was investigated.

The results are shown in Table 7, FIG. 3 and FIG.

Results: As is clear from Table 7, the cream of the present invention prepared by using an aliphatic alkyl phosphate ester salt and hydrogenated phospholipid in combination is excellent in the emulsified state, stability, and feeling of use. . Further, as is clear from Tables 4 and 5, the moisturizing effect persistence and the change in the dynamic friction coefficient are small, and the effect is superior to that of the comparative product.

Example 4 Composition of nutrient emulsion: (Oil phase) Liquid paraffin 5.0 (wt%) Squalane 1.0 Olive oil 4.0 Jojoba oil 4.0 Monocetyl phosphate 0.1 Hydrogenated soybean phospholipid (iodine value = 3.2, neutral lipid = 1.5%,
Phosphatidylcholine = 32.6%) 2.0 Cetanol 2.0 Sorbitan monostearate 1.0 Butylparaben 0.1 (Aqueous phase) Methylparaben 0.1 L-Arginine 0.05 Polyvinylpyrrolidone 0.1 Glycerin 3.0 Water balance Fragrance Trace method: Heat and dissolve the oil phase at 75-80 ° C. , Stir to mix evenly,
An aqueous phase, which is heated and dissolved at 70 to 80 ° C under stirring, is added to this and emulsified. After cooling to 50 ° C, add perfume and cool to 20-30 ° C with stirring. Then, this was further processed by a homogenizer to be sufficiently emulsified to obtain a nutritional emulsion.

Example 5 Foundation Cream Composition: (Oil Phase) Dimethylpolysiloxane (20 cm Stokes) 1.0
(Wt%) Solid paraffin 4.0 Cetanol 3.5 Liquid paraffin 10.0 Hydrogenated soybean phospholipids (iodine value = 8.2, neutral lipid = 12.2)
%, Phosphatidylcholine = 65.0%) 2.0 Butylparaben 0.1 (Aqueous phase) Methylparaben 0.1 Diglycerin 5.0 Monomyristyl phosphate L-Arginine 0.1 Montmorillonite 1.0 Iron oxide 3.0 Titanium oxide 6.0 Talc 10.0 Water balance Fragrance Trace production method: Oil phase 70 Dissolve by heating to ~ 80 ° C and mix uniformly. on the other hand,
The aqueous phase is heated at 70 to 80 ° C., the powder is uniformly dispersed by a disperser, and then the oil phase is added to emulsify the powder. 50 ° C under stirring
After cooling to, a fragrance was added, further cooled to 20 to 30 ° C., and sufficiently treated with a homogenizer to obtain a foundation cream.

[Brief description of drawings]

1 and 2 are drawings showing the results of a performance test of the oil-in-water emulsion composition obtained in Example 1, FIG. 1 is a plot of conductance of the skin surface against time, and FIG. 2 is a dynamic friction coefficient. Shows a plot of time against. 3 and 4 are drawings showing the results of performance tests of the oil-in-water emulsion composition obtained in Example 3, FIG. 3 is a plot of conductance of the skin surface against time, and FIG. 4 is a dynamic friction coefficient. Shows a plot of time against.

Claims (4)

[Claims] 1. An oil-in-water emulsion composition comprising a higher aliphatic phosphate ester salt, a hydrogenated natural phospholipid and a humectant, and being weakly acidic. 2. A higher aliphatic phosphate ester salt is represented by the following general formula (I): (In the formula, R ₁ is an alkyl or alkenyl group having 12 to 22 carbon atoms, X ₁ and X ₂ are the same or different, and are substituted with a hydrogen atom, an alkali metal, ammonium, or an alkyl group having 1 to 5 carbon atoms. A counter ion selected from the group consisting of ammonium, an alkanolamine having a hydroxyalkyl group having 2 to 3 carbon atoms and a basic amino acid, provided that X ₁ and X ₂ are present.
The oil-in-water emulsion composition according to claim 1, which is a compound represented by the formula (1) is a hydrogen atom). 3. A natural hydrogenated phospholipid derived from soybean or egg yolk, having an iodine value of 0 to 60 and a neutral lipid content of 40% by weight or less. The oil-in-water emulsion composition according to item 1. 4. The oil-in-water emulsion composition according to claim 1 or 3, wherein the hydrogenated natural phospholipid contains 15% by weight or more of phosphatidylcholine.