JPH0669930B2 - External skin preparation - Google Patents

Description

TECHNICAL FIELD The present invention relates to a skin external preparation, and more particularly to a skin external preparation capable of enhancing the water-retaining power of the stratum corneum and improving skin roughness.

[Conventional technology]

It has been known that moisture in the stratum corneum is important in order to moisturize and soften the skin. The retention of water is said to be due to the water-soluble components contained in the stratum corneum, that is, free amino acids, organic acids, urea or inorganic ions, and these substances may be used alone or in combination for the external preparation for medicated skin. Alternatively, it is used in cosmetics for the purpose of improving or preventing skin roughness.

In addition to this, many moisturizing substances having high affinity with water have been developed and used for the same purpose.

[Problems to be solved by the invention]

However, when these moisturizing substances are applied to the skin, the action is to supply water to the stratum corneum on the stratum corneum of the skin, and the effect is temporary,
It does not fundamentally improve the water-retaining ability of the stratum corneum and essentially prevent or cure the rough skin.

[Means for solving problems]

In such a situation, the inventors of the present invention have conducted diligent research to solve the above-mentioned problems, and found that the following general formula (I): (Wherein, R ¹ and R ² represent a linear or branched saturated or unsaturated hydrocarbon group having 10 to 26 carbon atoms), which fundamentally improves the water-retaining ability of the stratum corneum. The present invention has been completed by finding out that the effect is exhibited and that the effect can be further increased by using a surfactant together with this compound.

That is, the present invention provides a skin external preparation containing the compound represented by the formula (I), and a skin external preparation containing the compound represented by the formula (I) and a surfactant.

The compound represented by the formula (I) used in the present invention is a known compound, for example, Polyurethane Journal of Chemistry (Polish J. Chem.) 52, 1-59 (1).
It can be manufactured according to the method described in 978).

The amount of the compound represented by the formula (I) to be added to the skin external preparation of the present invention is not particularly limited, but in the case of an emulsion type skin external preparation, it is usually 0.001 to 50% by weight of the total composition (hereinafter simply expressed as%). ), Particularly 0.1 to 20% is preferable, and 1 to 50%, particularly 5 to 25% is preferable in the case of oily external preparation for skin based on liquid hydrocarbon such as squalene.

As the surfactant to be added to the skin external preparation of the present invention, any of a nonionic surfactant, an anionic surfactant, and an amphoteric surfactant can be used, among which a nonionic surfactant is particularly preferable. is there.

Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid monoglyceride, glyceryl ether and the like. Among them, the following general formula (II) (In the formula, R represents an alkyl group having 8 to 24 carbon atoms), a glyceryl ether represented by
R in the formula (II) is represented by the following formula (III) (In the formula, p represents an integer of 4 to 10, q represents an integer of 5 to 11,
and a distribution represented by p + q = 11 to 17 with p = 7 and q = 8 at the vertices) is particularly preferable.

The content of the surfactant is 0.01 to 20% of the total composition, especially 0.1%.
-5% is preferable.

The external preparation for skin of the present invention is roughly classified into a medical external preparation for skin and a cosmetic in its usage form.

Examples of the external medicated skin preparation include various ointments containing medicinal components. The ointment may be either one based on an oily base, one based on oil / water, or one based on an emulsion base of water / oil type. The oily base is not particularly limited, for example, vegetable oil, animal oil,
Examples include synthetic oils, fatty acids, and natural or synthetic glycerides. The medicinal component is not particularly limited,
For example, an analgesic anti-inflammatory agent, an antipruritic agent, a bactericidal disinfectant, an astringent agent, an emollient agent, a hormone agent and the like can be appropriately used as necessary.

When used as a cosmetic, in addition to the above essential ingredients, oils, moisturizers, UV absorbers, alcohols, chelating agents, pH adjusters, preservatives, thickeners that are commonly used as cosmetic ingredients. , Dyes, fragrances and the like can be combined in any combination.

As the cosmetics, various forms such as water / oil, oil / water emulsion cosmetics, creams, lotions, lotions, oily cosmetics, lipsticks, foundations, skin cleansers, hair nicks, hair styling agents, It can be used as a skin cosmetic such as a hair nourishing agent or a hair restorer.

[Action]

Although the details of the mechanism of action of the compound represented by formula (I) in the external preparation for skin of the present invention have not been completely elucidated, it reconstructs a lipid membrane between corneocytes to exert a water retaining function of the stratum corneum. It is considered to be a thing.

〔The invention's effect〕

Since the external preparation for skin of the present invention contains the compound (I) having such an action, it can exert an excellent improving and preventing effect on the rough skin.

〔Example〕

 Next, examples will be described.

Example 1 Using the compounds Ia to Id shown in Table 1 below, a mixture of petrolatum / compounds (Ia to Id) = 3/1 (weight ratio) (invention product 1) and petrolatum (comparative product 1). The skin conductance and the skin roughness were evaluated by the following test methods. The results are shown in Table 1.

(Test method) Ten women aged 20 to 50 who have rough skin on the cheeks in winter are used as test subjects, and different skin external preparations are applied to the left and right cheeks for 2 weeks. On the day after the application for two weeks was completed, the following items were tested.

(1) Skin conductance After washing the face with warm water of 37 ℃, in a room with temperature of 20 ℃ and humidity of 40%, 20
After resting for a minute, the water content of the stratum corneum was measured with a skin conductance meter (IBS). The smaller the conductance value is, the rougher the skin is, and when the conductance value is 5 or less, the skin is severely rough. On the other hand, if this value is 20 or more, almost no rough skin is observed.

(2) Skin Roughness Score Rough skin was visually observed and judged according to the following criteria. The score is shown as an average value.

Example 2 A skin external preparation (emulsified cosmetic) having the composition shown in Table 2 below was produced using the compounds Ia to Id in Example 1, and the skin roughening improving effect was evaluated by the same method as in Example 1. . The results are shown in Table 3.

Example 3 Emulsion An emulsion was prepared according to the following formulation. Mix and heat the water phase ingredients and keep at 70 ° C. Separately, the oil phase components are heated and mixed at 80 ° C., the above-mentioned water phase components are gradually stirred and added, and then the mixture is uniformly emulsified by a homomixer. After emulsification, by heat exchanger
The emulsion was cooled to 30 ° C.

Example 4 Cleansing Cream A cleansing cream was prepared according to the following formulation. The oil phase components are mixed and heated to 80 ° C. Separately water phase component 70 ℃
What was heated and mixed with was added to the above-mentioned oil phase component and uniformly emulsified by a homogenizer, and then cooled to 30 ° C by a heat exchanger to obtain a cleansing cream.

Example 5 Lotion A lotion was prepared according to the following formulation. Glycerin and propylene glycol were added to purified water and dissolved at room temperature.
Use as purified water. On the other hand, an emollient, a surfactant, a preservative and a fragrance are added to ethanol and dissolved at room temperature, and the purified water part is added to this to be solubilized. Further, after the color was adjusted with a dye, it was filtered to obtain a lotion.

Example 6 Lipstick A lipstick was prepared according to the following formulation. Heat and melt the base material and mix evenly. A coloring material is added to this, and the mixture is kneaded by a roll mill, uniformly dispersed, and then remelted to add a fragrance. The solidified product is taken out of the mold and loaded into a container. Further, after adjusting the appearance of the stick, it was passed through a flame (framing) to make the surface uniform and obtain lipstick.

(% By weight) Base: Compound Ic 5.0 Castor oil 45.0 Hexadecyl alcohol 23.0 Lanolin 4.0 Beeswax 5.0 Ozokerite 4.0 Candelilla wax 4.0 Carnauba wax 2.0 Tocopherol 0.1 Butylparaben 0.1 Coloring material: Titanium oxide 2.0 Red 202 0.5 Red 204 2.5 Red 227 Al Lake 2.5 Orange No. 201 0.2 Perfume 0.1 Example 7 Emulsion type emulsion An emulsion type emulsion was prepared according to the following formulation.
Oil phase ingredients are mixed, melted by heating and kept at 80 ° C. Separately, the powder component is added to the aqueous phase component to disperse it, and the mixture is heated to 70 ° C. The above oil phase component is added to this aqueous phase component and emulsified and dispersed by an emulsifying machine. The obtained emulsion was cooled to 30 ° C by a heat exchanger to obtain an emulsion type emulsion.

(% By weight) Oil phase component: Compound Id 3.0 Stearic acid 5.0 Cetostearyl alcohol 1.0 Jojoba oil 15.0 Glycerin monostearate 2.0 Propylene glycol monolaurate 3.0 Aqueous phase component: Propylene glycol
4.0 Triethanolamine 1.2 Methylparaben 0.3 Fragrance 0.1 Purified water Balance Powder component: Titanium oxide 8.0 Talc 4.0 Iron oxide 0.5 Example 8 Hair Tonic A hair tonic was prepared according to the following formulation.

 (Wt%) Compound Ib 0.2 Menthol 0.2 Piroctone auramine (antidandruff agent) 0.1 Methyl nicotinate 0.1 Ethanol 50.0 Purified water balance

Claims (2)

[Claims] 1. The following general formula (I): (In the formula, R ¹ and R ^{2 each} represent a linear or branched saturated or unsaturated hydrocarbon group having 10 to 26 carbon atoms), and a skin external preparation containing the compound represented by the formula: 2. The following general formula (I): (In the formula, R ¹ and R ² represent a linear or branched saturated or unsaturated hydrocarbon group having 10 to 26 carbon atoms) and a skin external preparation containing a surfactant.