(1,1'-Biphenyl)-4,4'-diamine, N,N,N',N'-tetraphenyl- 15546-43-7 EINECS 239-599-0 N,N,N',N'-Tetraphenyl(1,1'-biphenyl)-4,4'-diamine N,N,N1,N1-Tetraphenylbenzidine Tetraphenylbenzidine