C.I. 22120; C.I. Direct Red 28; C.I. Direct Red 28, disodium salt; C.I. Direct Red 28, disodium salt (8CI); Congo red; Direct Red 28; Congo red (0.1% in water)[for titration]; Congo red (0.1% in water); Direct Scarlet 4B; disodium 3,3'-[biphenyl-4,4'-diyldi(E)diazene-2,1-diyl]bis(4-aminonaphthalene-1-sulfonate); disodium 4-amino-3-[4-[4-[(1-amino-4-sulfonato-2-naphthyl)azo]phenyl]phenyl]azo-naphthalene-1-sulfonate; Direct Red 28
T:Toxic;