CHROMENE COMPOUNDS

摘要

Photochromic compounds having such a high fading rate as to prevent color tone changes during fading, being reduced in the discoloration upon deterioration, and having an excellent persistence of photochromism. The photochromic compounds refer to novel chromene compounds each bearing a substituted phenyl group and an alkyl group respectively at the 2- and 5-positions of a naphthopyran ring and represented by, for example, general formula (1) wherein R<1> is an alkyl group, R<2> and R<3> are each a substituted phenyl group, and R<4> and R<5> are each a substituent.