Patent ID: 7794907

Claim:
A hydrazone compound of a general formula (1): wherein Ar 1 represents an arylene group optionally having a substituent; Ar 2 represents an aryl, heterocyclic, aralkyl or alkyl group optionally having a substituent; Ar 3 represents an aryl, heterocyclic, aralkyl or thienylalkyl group optionally having a substituent; Ar 4 represents a hydrogen atom, or an aryl, heterocyclic, aralkyl or alkyl group optionally having a substituent; Ar 5 represents an aryl or heterocyclic group optionally having a substituent; Ar 6 represents a hydrogen atom, or an aryl, heterocyclic, aralkyl or alkyl group optionally having a substituent; with the proviso that, to the carbon atom to which the group ═CAr 3 Ar 4 bonds, a divalent aromatic or heterocyclic group may bond in place of the group ═CAr 3 Ar 4 bonds; to the nitrogen atom to which ═CAr 5 Ar 6 bonds, a divalent aromatic or heterocyclic group may bond in place of the group ═CAr 5 Ar 6 bonds; R 1 , R 2 and R 3 may be the same or different, each representing a hydrogen atom, or an alkyl, aryl, heterocyclic or aralkyl group optionally having a substituent; n indicates 2; two R 2 s and two R 3 s each may be the same or different; wherein the optional substituent of Ar 5 being selected from the group consisting of a halogen atom, a perfluoroalkyl croup, an alkyl croup, an alkoxy croup, a mono- or difluoroalkyl croup and a dialkylamino group.