Process for preparing a photochromic compound, the obtained photochromic compound and the cosmetic composition containing it

摘要

Preparing an improved photochromic compound with a DELTA ( DELTA E) parameter≥7 comprises treating an initial photochromic compound (a metal oxide, metal oxide hydrate, or complex of the two) (II) at 400-1000 degrees C in the presence of a metal compound (an oxide or hydroxide of Li, K and/or Na) (III). Also claimed are: (1) photochromic compounds (IV) obtained according to (I), and (2) cosmetic compositions (V) containing (IV).