Synonyms: Anthra[2,1,9-mna]naphth[2,3-h]acridin-5(16H)-one,3-[(9,10-dihydroxy-1-anthryl)amino]-10,15-dihydroxy-, tetrakis(hydrogensulfate) (ester), tetrasodium salt (8CI);Anthra[2,1,9-mna]naphth[2,3-h]acridin-5(16H)-one,3-[[9,10-bis(sulfooxy)-1-anthracenyl]amino]-10,15-bis(sulfooxy)-, tetrasodiumsalt (9CI); Anthrasol Grey ITR; C.I. Solubilised Vat Black 25, tetrasodiumsalt; Indigosol Grey 15G