Process for dyeing hydrophobic fibre material from aqueous bath containing untreated disperse dye and to adjust the exhausted dye bath for further use

摘要

A process is described for dyeing hydrophobic fibre material with unfinished disperse dyes from an aqueous liquor, which comprises dissolving one or more such dyes in water at a temperature of 50 to 150 C. by means of a surfactant or surfactant mixture with a hydrotroping or solubilizing action on disperse dyes, bringing the dye solution together with the substrate in a dyeing apparatus, then heating the dyeing liquor to the dyeing temperature and completing the dyeing at that temperature and then removing the substrate and restoring the exhausted dyeing liquor to the original composition by adding water, surfactant and dye and using it again for dyeing.