Synonyms: 3-Indolinone,5,7-dichloro-2-(1-oxonaphtho[2,1-b]thien-2(1H)-ylidene)- (8CI); 3H-Indol-3-one,5,7-dichloro-1,2-dihydro-2-(1-oxonaphtho[2,1-b]thien-2(1H)-ylidene)- (9CI);Naphtho[2,1-b]thiophene, 3H-indol-3-one deriv.; C.I. 73665; C.I. Vat Brown 42;Indanthren Printing Brown R; Indanthrene Printing Brown R; Nako Fast Brown R