Synonyms: 2,7-Naphthalenedisulfonicacid, 4,4'-[(3-sulfo-4,4'-biphenylylene)bis(azo)]bis[3-amino-, pentasodium salt(7CI,8CI); 2,7-Naphthalenedisulfonic acid,4,4'-[(3-sulfo[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-amino-, pentasodium salt(9CI); Trypan red (6CI); C.I. 22850; CI 22850