JPH0669931B2 - 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): (In the formula, R ¹ and R ² represent a linear or branched saturated or unsaturated hydrocarbon group having 10 to 26 carbon atoms) or a salt thereof is fundamental to the water retention ability of the stratum corneum. The present invention has been completed based on the finding that the effect of improving the compound is exhibited, and that the effect can be further increased by using a surfactant together with this compound or a salt thereof.

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

The compound represented by the formula (I) used in the present invention is a known substance, for example, East German Patent No. 92940 (197).
It can be synthesized according to the method of 3). Examples of the salt include those usable for cosmetics such as alkali metal salts.

The amount of the compound represented by the formula (I) or a salt thereof to be added to the skin external preparation of the present invention is not particularly limited, but in the case of an emulsified skin external preparation, it is usually 0.001 to 50% by weight of the total composition.
(Hereinafter simply indicated by%), 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) (Wherein R represents an alkyl group having 8 to 24 carbon atoms) is preferred, and 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 medicated external preparation for skin and a cosmetic in its use 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]

The details of the mechanism of action of the compound represented by formula (I) or a salt thereof in the external preparation for skin of the present invention have not been completely elucidated, but this has the effect of reconstructing a lipid membrane between corneocytes to retain water in the stratum corneum. It is thought that it exerts.

〔The invention's effect〕

Since the external preparation for skin of the present invention contains the compound (I) or a salt thereof having such an action, it can exert excellent improving and preventing effects on skin roughness.

〔Example〕

 Next, examples will be described.

Example 1 Using Compounds Ia-Id, Vaseline / Compound (Ia-Id) =
The skin conductance and skin roughness of the 3/1 (weight ratio) mixture (invention product 1) and vaseline (comparative product 1) were evaluated by the following 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 Compounds Ia to Id were used to produce a skin external preparation (emulsion cosmetic) having the composition shown in Table 2 below, 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 According to the above formulation, the oil phase components are mixed, dissolved by heating and kept at 70 ° C. Similarly, the above water phase components are heated and mixed at 70 ° C., and the above oil phase part is added to this water phase part and emulsified by an emulsifying machine. The emulsion was cooled with a heat exchanger to a final temperature of 30 ° C. to prepare an emulsion.

This emulsion had a high effect of improving rough skin and showed excellent moisturizing ability.

Example 4 Emulsion type emulsion According to the above formulation, the oil phase components are mixed, dissolved by heating and kept at 70 ° C. After the powder component is added to the above aqueous phase component and dispersed, 70 ° C
Heat to. The above oil phase portion is added to this water phase portion and emulsified and dispersed by an emulsifying machine. Heat the emulsion to a final temperature of 30.
An emulsion type emulsion was prepared by cooling the mixture to 0 ° C. and then filling it.

This emulsion type foundation had a high effect of improving rough skin and showed excellent moisturizing ability.

Example 5 Lipstick According to the above formulation, microcrystalline wax, candelilla wax, castor oil, compound (Ia), jojoba oil, olive oil, and lanolin are heated and dissolved at 90 ° to 100 ° C., after which pigments are added and well stirred and dispersed to deaerate. Add the fragrance to it and pour into a lipstick molding machine, cool to 15 ° -20 ° C,
A sticky lipstick was prepared by removing from the mold.

This lipstick had a high effect of improving rough skin and showed an excellent moisturizing ability.

Example 6 W / O type pine surge cream According to the above prescription, add soap powder to purified water and heat.
Keep at ℃. Mix the oil phase ingredients and heat to 70 ° C. After performing the preliminary emulsification by adding the above-mentioned water phase part to this oil phase part,
Emulsify uniformly with a homomixer and cool to near room temperature with a heat exchanger.

This pine surge cream has a high effect of improving rough skin and has an excellent moisturizing effect.

Example 7 Pack (peel-off type) According to the above formulation, the aqueous phase components are mixed, dissolved by heating and kept at 70 ° C. Similarly, the above oil phase components are heated and mixed at 70 ° C., added to the above water phase portion and emulsified by an emulsifying machine. A powder component and a film forming agent are added to this emulsion and mixed. A pack was prepared by cooling the emulsion to a final temperature of 30 ° C. with a heat exchanger and then filling it.

This pack had a high effect of improving rough skin and showed an excellent moisturizing ability.

Example 8 Hair Tonic The following components were dissolved by heating at 70 ° C and cooled to obtain a hair tonic.

Claims (2)

[Claims] 1. 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) or a skin external preparation containing a salt thereof. 2. 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) or a salt thereof and a skin external preparation containing a surfactant. .