PURPOSE: To obtain a new photo-chromic compound exerting clear definitive color shade changes from colorless/yellow, red, to golden or blue and useful for an optical memory layer capable of cyclical writing and erasing of information and a color filter or the like.

CONSTITUTION: This compound of formulae I or II, e.g. a compound of formula III is obtained by reacting a compound of formulae IV or V (Y is a halogen, -NO2; Y1 is H, a halogen or the like) with an equivalent amount of a compound of the formula R9O-M+ (M+ is an alkali metal cation, ammonium cation) in the presence of a polar non-protonic or protonic solvent (suitably THF or the like), preferably at 50 to 150°C. In formulae I or II, X is -O-, -S- or the like; R1, R2 are each H, a 1-4C alkyl or the like; R3 is -OR9 (R9 is a 6-14C aryl non-substituted or substituted by a 1-12C alkyl or the like); R4 is H, a halogen or the like; R5, R6 are each R1, or R5 and R6 join together to form 1,2-benzobuta-1,3-dien-1,4-diyl.