摘要:
A novel fulgimide compound in which the nitrogen atom of the imide ring is substituted by a phenyl group having an electron-attracting group at least at the meta position, which is represented by the following general formula (I): ##STR1## [wherein the group (a) of the following formula is a divalent aromatic hydrocarbon group or unsaturated heterocyclic group, each of which may have a substituent(s); ##STR2## the group (b) of the following formula is a norbornylidene, bicyclo[3.3.1]nonylidene or adamantylidene group, ##STR3## and R.sup.2 is an electron-attracting group] and its use as a photochromic material.The fulgimide compound of the present invention has a higher color density in a color-developed state than conventional photochromic compounds.