Patent ID: 8147726

Claim:
A chromene compound represented by the following formula (1): wherein R 1 and R 2 are each independently an alkyl group having 1 to 9 carbon atoms, cycloalkyl group having 3 to 12 carbon atoms, perfluoroalkoxy group having 1 to 6 carbon atoms, aralkyl group having 7 to 11 carbon atoms, aralkoxy group having 7 to 11 carbon atoms, aryl group having 6 to 10 carbon atoms, aryloxy group having 6 to 10 carbon atoms or alkoxy group having 1 to 6 carbon atoms, with the proviso that R 1 and R 2 cannot be alkoxy groups having 1 to 6 carbon atoms at the same time; R 3 and R 4 are each independently a hydrogen atom, hydroxyl group, alkyl group having 1 to 9 carbon atoms, cycloalkyl group having 3 to 12 carbon atoms, alkoxy group having 1 to 6 carbon atoms, aralkyl group having 7 to 11 carbon atoms, aralkoxy group having 7 to 11 carbon atoms, aryl group having 6 to 10 carbon atoms or aryloxy group having 6 to 10 carbon atoms; R 1 and R 3 or R 2 and R 4 may be bonded together to form an alkylene group or alkylenedioxy group; R 5 and R 6 are each independently a hydroxy group, alkyl group having 1 to 9 carbon atoms, cycloalkyl group having 3 to 12 carbon atoms, alkoxy group having 1 to 6 carbon atoms, aralkyl group having 7 to 11 carbon atoms, aralkoxy group having 7 to 11 carbon atoms, aryl group having 6 to 10 carbon atoms, aryloxy group having 6 to 10 carbon atoms, cyano group, nitro group, halogen atom, halogenoalkyl group having 1 to 6 carbon atoms or halogenoalkoxy group having 1 to 6 carbon atoms, and m and n are each independently an integer of 0 to 4.