Substantivity and spatial structure of soluble polycyclic dyes for dyeing cellulose fibres

Several polycyclic dyes, derivatives of imidazole and imide derivatives of a perylenetetracarboxylic-3,4,9,10 anhydride have been synthesized. Dyes obtained by adding sulpho groups to original dye molecules were used to dye cellulose fibres in the same way as with direct dyes. The resultant dyeings have a good fastness to washing, abrasion and light. Probable sites of a substitution of sulpho groups in dyes were determined by calculating a total energy of molecules by means of a semiempirical molecular orbital AM1 method and also a reason of a substantivity of imidazole dyes was explained.