GB748895A - Process for printing textile materials - Google Patents

Abstract

Discharge printing is effected on linear aromatic polyester textiles, e.g. polyethylene terephthalate textiles, by padding the textile with an aqueous dispersion of a dischargeable dyestuff, drying, applying locally a discharge printing paste and subsequently steaming, preferably at superatmospheric pressure. The discharge paste containing, for example, sodium or zinc formaldehyde-sulphoxylate may also contain dyestuffs, e.g. vat dyes, or dyestuff components which are not decomposed by the discharge agent. Two or more discharge printing pastes may be employed and the process can be combined with a direct printing step to modify locally the ground or discharge shades. In examples, polyester cloth is padded with an azo dye liquor containing an aqueous emulsion of sulphonated sperm oil and pine oil, sodium m-nitrobenzene - sulphonate and gum tragacanth, dried and printed with a zinc formaldehyde - sulphoxylate discharge paste containing p - hydroxydiphenyl, an aqueous emulsion of sulphonated sperm oil and pine oil, and gum tragacanth thickening together with, in one case, diethyl tartrate, and in another case, disodium dinaphthylmethane - disulphonate and a vat dyestuff. In one example, the padded cloth is first printed with a vat dyestuff paste and then with the discharge paste. The cloth is finally steamed, and when a vat dyestuff has been applied it is oxidized with aqueous nitrous acid, rinsed and dried. Specifications 701,968 and 712,418 are referred to.