External preparation for skin

Abstract

Disclosed is an external preparation for the skin, which contains a surfactant or a preservative that is believed to be a causal substance of skin irritation in a reduced amount and therefore has low irritating properties, and also has high preparation stability. Specifically disclosed is an external preparation for the skin, which is characterized by comprising a rhododendrol represented by general formula (1) and / or a derivative thereof, a nonionic surfactant selected from a sucrose fatty acid ester and a polyglycerin fatty acid ester, and a polyhydric alcohol. The external preparation for the skin has low skin irritation properties, an excellent preservative / anti-fungal effect and high preparation stability. In general formula (1), R represents a hydrogen atom, an acyl group having 2 to 20 carbon atoms, or a sugar residue of a monosaccharide or a disaccharide.

Description

technical field The present invention relates to an external preparation for skin which is less irritating to skin, has excellent long-term storage stability, and has high skin beautifying and whitening effects. Background technique In external skin preparations generally formulated as cosmetics, various surfactants are used for the solubilization, emulsification, and dispersion of insoluble components; among them, they are widely used because they are safe to the skin and easy to ensure the stability of the preparation. Polyoxyethylene addition type nonionic surfactant. However, the solubility state of polyoxyethylene addition type nonionic surfactants in water and oil and their functions as surfactants are mostly affected by temperature. Since the compounding amount of the agent is set to a large amount, etc., the irritation to the skin cannot be ignored. In addition, preservatives such as p-hydroxybenzoic acid and phenoxyethanol are widely used in external skin prepar...

AI Technical Summary

Problems solved by technology

Although it is known that rhododendron and its derivatives are ingredients that can prevent or improve skin pigmentation such as spots and freckles (see patent documents 1 to 3), rhododendol and its derivatives have not been used for antiseptic and anti-mold purposes.

In addition, rhododendol and its derivatives have low solubility in water; in preparations containing rhododendol and its derivatives, especially in cosmetic water with almost no viscosity, more than usual is used in order to improve the stability of the preparation. Polyoxyethylene addition nonionic surfactants act as solubilizers and must be managed in combination with lower alcohols, thus becoming a factor that increases skin irritation

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