1,5-Dihydroxy-4,8-diamino- and 1,8-dihydroxy-4,5-diaminoanthraquinone-β-ethers and thioethers. Blue dyes for synthetic polymer fibres

Condensation of mono- and di-bromo-derivatives of 1,5-dihydroxy-4,8-diaminoanthraquinone and of 1,8-dihydroxy-4,5-diaminoanthraquinone with phenols and thiols afforded the corresponding β-ethers and thioethers. These compounds coloured polyester in bright reddish-blue to greenish-blue hues of generally good fastness to light and sublimation. The colour of the dyes is discussed with respect to the nature and orientation of the β-substituent.