Patent ID: 8883888

Claim:
A diarylamine compound represented by the following formula (I), the diarylamine compound having a hydrogen of the N—H moiety having a N—H shift value in 1 H-NMR of 8.30 ppm to 9.00 ppm as measured in deuterated dimethyl sulfoxide (TMS, δ ppm): wherein in the formula (I), A 1 and A 2 each independently represents an aromatic group which is optionally substituted with an alkyl group having 1 to 10 carbon atoms, a halogen-substituted alkyl group having 1 to 10 carbon atoms, a halogen atom, a cyano group, or a nitro group; R 1 , R 3 and R 4 each represent a hydrogen atom; R 2 represents —C(═O)—OR′″, and R′″ represents an alkyl group having 1 to 10 carbon atoms, or an aromatic group having 4 to 30 carbon atoms; wherein R′″ is optionally substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, an aralkyl group having 1 to 20 carbon atoms, an aromatic group having 6 to 30 carbon atoms, a cyano group, a nitro group, a sulfo group, —OR a , —O—C(═O)—R a , —C(═O)—OR a , —O—C(═O)—OR a , —NR c —C(═O)—R a , —C(═O)—NR a R b , —O—C(═O)—NR a R b , —SR a , —S(═O)—R a , or —S(═O) 2 —R a ; R a , R b and R c each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group.