Chromene compound

A chromene compound represented by the following formula (5):

• wherein R1 is a hydroxyl group, alkyl group, haloalkyl group, cycloalkyl group, alkoxy group, amino group, heterocyclic group having a ring member nitrogen atom and bonded to a benzene ring to which the heterocyclic group is bonded via the nitrogen atom, cyano group, nitro group, formyl group, hydroxycarbonyl group, alkylcarbonyl group, alkoxycarbonyl group, halogen atom, aralkyl group, aralkoxy group, aryloxy group, aryl group, heteroaryl group, alkylthio group, cycloalkylthio group, arylthio group, heteroarylthio group or group having a siloxane bond, “a” is an integer of 0 to 4, provided that when “a” is 2 to 4, a plurality of R1's can be the same or different, or two R1's are bonded together to form a ring, R2 and R3 are each an alkyl group, aryl group, heteroaryl group, group represented by the following formula (2), or group represented by the following formula (3):
• wherein R4 is an aryl group or heteroaryl group, R5 is a hydrogen atom, alkyl group or halogen atom, and “m” is an integer of 1 to 3,
• wherein R6 is an aryl group or heteroaryl group, and “n” is an integer of 1 to 3, or R2 and R3 form an aliphatic ring together with carbon atoms to which R2 and R3 are bonded, C* is a Spiro carbon atom, a spiro ring A represented by the following formula is a saturated hydrocarbon ring or unsaturated hydrocarbon ring having 4 to 12 carbon atoms constituting the ring, and at least one ring member carbon atom constituting the Spiro ring A is a group represented by the following formula (4):
• wherein R7 and R8 are each an alkyl group having 3 or more carbon atoms, aralkyl group, cycloalkyl group, aryl group or heteroaryl group, and R9 is a hydroxyl group, alkyl group, haloalkyl group, cycloalkyl group, alkoxy group, amino group, heterocyclic group having a ring member nitrogen atom and bonded to a benzene ring to which the heterocyclic group is bonded via the nitrogen atom, cyano group, nitro group, formyl group, hydroxycarbonyl group, alkylcarbonyl group, alkoxycarbonyl group, halogen atom, aralkyl group, aralkoxy group, aryloxy group, aryl group, heteroaryl group, alkylthio group, cycloalkylthio group, arylthio group, heteroarylthio group or group having a siloxane bond, “b” is an integer of 0 to 4, provided that when “b” is 2 to 4, a plurality of R9's can be the same or different, or two R9's are bonded together to form a ring.