PHOTOCHROMIC COMPOUND, ITS PRODUCTION AND COSMETIC COMPOSITION CONTAINING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a sufficientΔE30 value by increasing a valve of theΔ(ΔE) of an originally photochromic compound by subjecting the photochromic com pound such as a metal oxide or a hydrated metal oxide to heat treatment in the presence of an alkali metal component in a production of the photochromic compound having >=7 of a parameterΔ(ΔE). SOLUTION: This process comprises heat treatment of a photochromic compound of a metal oxide, a hydrated metal oxide or a metal oxide and/or a hydrated metal oxide composite type at 400-1,000 deg.C in the presence of a metal component comprising an oxide and/or hydroxide of lithium, sodium or potassium. There is provided with a cosmetic composition containing the photochromic compound obtained by the method. As an elucidation of the generation of the photochromic property of doped titanium oxide, it is said that in a case of doping an iron ion having a valence of 3+ and 4+ with a photochromic titanium oxide of anatase type, the photochromic property of the anatase type substituted with titanium atom having a valence 4+ increases in an anatase crystal lattice.