| Abstract: | Dyes incorporating β-isothioureidopropionamide and β-isnthioureidoethyl salt groups have been synthesized by reaction of the corresponding bromide or iodide with thiourea. Such dyes can be applied in the cationic form to wool and bask-dyeable fibres, and then, by raising the pH to 9–10, decomposed on the fibre to give fast dyeings. These dyes can also be successfully applied as disperse dyes to appropriate fibres by carrying out the decomposition before dyeing in the presence of dispersing agents. By a combination of these two systems, both components of wool polyester blends can be dyed with the same dye. The high washfastness of isothiouronium dyes on wool is thought to be due to insolubilization within the fibre rather than to mixed disulphide formation with cystine. |
