Direct blue 6; 2,7-naphthalenedisulfonic acid,3,3'-[(1,1'-biphenyl)-4,4'-diylbis(azo)]bis(5-amino-4-hydroxy)- tetrasodium salt; Airedale blue 2bd; Aizen direct blue 2bh; Amanil blue 2bx; Atlantic blue 2b; Atul direct blue 2b; Azomine blue 2b; Belamine blue 2b; Bencidal blue 2b; Benzanil blue 2b; Benzo blue bba-cf; Benzo blue bbn-cf; Benzo blue gs; Blue 2b; Blue 2b salt; Chlorazol blue b; Ci 22610; C.i. direct blue 6; Diazol blue 2b; Diphenyl blue 2b; Direct blue m2b; Hispamin blue 2b; Kayaku direct; Kayaku direct blue bb; Nippon blue bb; Paramine blue 2b; Pheno blue 2b; Tertrodirect blue 2b; Tetrasodium 3,3'-[4,4-biphenylenebis(azo)] bis(5-amino-4-hydroxy)-2,7-naphthalenedisulfonate; C.i. 22610; C.i. direct blue 6, tetrasodium salt; Azocard blue 2b; Brasilamina blue 2b; Calcomine blue 2b; Chloramine blue 2b; Chlorazol blue bp; Chrome leather blue 2b; Cresotine blue 2b; Diacotton blue bb; Diamine blue 2b; Diamine blue bb; Diaphtamine blue bb; Diazine blue 2b; Diphenyl blue kf; Diphenyl blue m2b; Direct blue a; Direct blue 2b; Direct blue bb; Direct blue gs; Direct blue k; Direct blue wbb; Enianil blue 2bn; Fenamin blue 2b; Fixanol blue 2b; Indigo blue 2b; Mitsui direct blue 2bn; Naphtamine blue 2b; Niagara blue b; Niagara blue 2b; Phenamine blue bb; Pontamine blue bb; Vondacel blue 2b.