abstract |
Process for the preparation of N,N'-disubstituted 1,4-dianinoanthraquinones in which R is an aliphatic or aromatic radical, characterized in that 1,4-dihydroxyanthraquinones are reacted with aliphatic or aromatic amines in the presence of a readily water-soluble, dipolar-aprotic solvent (e.g. NMP) and of a second solvent, different from the first. |