Patent ID: 7745081

Claim:
A diphenyl amine derivative represented by the following general formula (1): (In the general formula (1), R 1 to R 12 each are a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, a phenoxy group which may have a substituent, an aryl group which may have a substituent, or an aralkyl group which may have a substituent, Z is a ring structure linked with a benzene ring, which is a 4 to 8-membered ring including a hydrogen atom, a nitrogen atom, an oxygen atom, a carbon atom or a sulfur atom, m1, m2, n1, n2 each are 0 or 1, m1+n1 is 1 or 2, and m2+n2 is 1 or 2), however neither m1+n1 nor m2+n2 become 1 at the same time, wherein a ring structure including a benzene ring in the diphenyl amine derivative represented by the general formula (1) is a structure represented by the following formula (2-1) or (2-2):