Patent ID: 7057054

Claim:
A photochromic material comprising a compound having a ring opening quantum yield of 10 −3 or lower, which is a diheteroarylethene, represented by the following formula (I): wherein, in the formula (I), A represents following substituents (i) or (ii), and B represents following substituents (iii) or (iv); wherein, in the substituents (i) and (ii), R 1 represents an alkoxy group, R 2 represents -Q-Ar, Q represents a direct bond or a divalent group and Ar represents an aromatic hydrocarbon ring or an aromatic heterocycle which are optionally substituted, R 3 represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a fluoroalkyl group; a cyano group, or an aryl group which is optionally substituted, and Y represents —O— or —S—; and in the substituents (iii) and (iv), R 4 represents an alkoxy group, R 5 represents -Q-Ar, Q represents a direct bond or a divalent group and Ar represents an aromatic hydrocarbon ring or an aromatic heterocycle which are optionally substituted, R 6 represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a fluoroalkyl group, a cyano group, or an aryl group which is optionally substituted, and Z represents —O— or —S—.