Abstract: The dyes according to the invention consist of a chromophore and a radical which, on heating, forms an isocyanate or isothiocyanate group. The latter reacts with a suitable group in the environment. Dyeings of excellent thermomigration fastness are obtained. The disclosed dyes are of the formulae ##STR1## where F is the radical of an azo, anthraquinone or tricyanovinyl dye which is free of water-solubilizing groups,B and B' are each independently of the other a direct bond or a bridge member, selected from the group consisting of a straight-chain or branched alkylene group having 2 to 8 C atoms or one of the following groups ##STR2## where R is hydrogen or C.sub.1 -C.sub.6 alkyl, n is an integer from 1 to 8 and m is an integer from 2 to 4,Z is O or S,V is a group which at a temperature between 180.degree. and 240.degree. C. is eliminated as a radical HV, andV' is a direct bond which is cleaved at a temperature between 180.degree. and 240.degree. C.

Abstract: A process for dyeing and printing blends of wool and polyester fibres which comprises the use of dyes of the formula ##STR1## wherein A is the radical of a monofunctional or polyfunctional tertiary amine, X is an anion and F is the radical of a dye of the disperse class. The process yields tone-in-tone dyeings.