| 摘要 |
PROBLEM TO BE SOLVED: To obtain a skin preparation for external use having melanogenesis inhibitory action and tyrosinase activity inhibitory action, thus excellent in mitigating pigmentation after suntan, freckles and chloasma, excellent in skin whitening effect, and also excellent in safety. SOLUTION: This skin preparation for external use contains, as active ingredient(s), 0.001-20 (pref. 0.01-10, more pref. 0.1-7)wt.% of compound(s) of formula I and/or formula II. This skin preparation can be made into formulations such as cream, ointment, gel, lotion, milky lotion, stick, pack, or organic solvent solution through blending the active ingredient(s) with, according as appropriate, commonly used ingredients such as moisturizing agent, antioxidant, oily ingredient, UV rays absorber, surfactant, thickening agent, alcohols and other skin whitening agent. The respective compounds of formula I and formula II have skin whitening effect greater than those for hydroquinone. These compounds have been known, and can be isolated from relevant plants. |
