Synonyms: 2-Pyrazolin-5-one,4,4'-(3,3'-dimethoxy-4,4'-biphenylylenebisazo)bis[3-methyl-1-phenyl- (6CI);3H-Pyrazol-3-one,4,4'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[2,4-dihydro-5-methyl-2-phenyl-(9CI); C.I. Pigment Red 41 (8CI);Bis(1-phenyl-3-methyl-5-oxo-4-pyrazolinyl)-4,4'-disazo-3,3'-dimethoxybiphenyl;C.I. 21200; Dianisidine Red; Electra Red; Electra Red (Yellowish) R-128;Pigment Red 41; Pigment Red BB; Resamine Fast Red BB; Rubber Fast Red BBE;Vulcan Fast Red BBE