Process for the localized lightening, white discharging or colored discharging of dyeings on textile sheet-like structures using dye dissolving agent

摘要

In order to achieve lighter patterned effects on a background of a deeper color, aqueous printing pastes containing, additionally to thickeners and other conventional printing assistants, assistants which have dissolving properties for the dyestuffs at elevated temperatures and which do not attack the fibers under thermosol conditions, are applied to textile webs which have been dyed in a finished manner with suitable dyestuffs or have only been impregnated therewith, after which the goods treated in this way are subjected to a steaming process or to a dry heat treatment. In accordance with the process it is possible to effect a uniform lightening, "white discharging" or "colored discharging" of dyeings, particularly dyeings of synthetic fibers with disperse dyestuffs and also dyeings of natural fibers or mixtures thereof with disperse dyestuffs, vat dyestuffs, leuco esters thereof and developing dyestuffs. Dyestuff-dissolving assistants of the type used are anionic, cationic or nonionic compounds of various structures.