Aryl sulphonyl-anthraquinone dyestuffs

摘要

The invention comprises anthraquinone dyes of the formula wherein R is an unsubstituted or substituted aryl, R1 is H, halogen or -CN or unsubstituted or substituted -SR5 or -SO2R5, R2 is H, -OH, alkoxy, amino or -NH-SO2-R, R3 and R4 may each be H, halogen, -NO2, -OH or amino and R5 is unsubstituted or substituted alkyl, aralkyl or aryl. The dyes may be prepared by oxidizing the corresponding 2-arylthioanthraquinone, e.g. with H2O2. The dyes are suitable for colouring aromatic polyester or cellulose acetate materials. Examples are given.