GB812362A - Process for the manufacture of dyed and durably crimped fibrous materials of linear polyesters - Google Patents

Abstract

Dyed and durably crimped polyester fibres are produced by impregnating the stretched or unstretched polyester filaments, before, simultaneously with or after their formation into a tow, with an aqueous dispersion of a waterinsoluble dyestuff or an aqueous solution of a water-soluble developable derivative of such a dyestuff having an affinity for the fibres, removing excess liquor from the filaments in the form of a tow, stretching if the filaments are not already oriented, drying, mechanically crimping and then fixing the dyeing and the crimp by steaming under pressure. Impregnation with the dyestuff liquor may also be effected both before and after stretching, when effected. The tow may be cut into staple fibres before or after steaming, or alternatively it may be worked up into a roving or yarn. Steaming may be effected at 110-140 DEG C. on the tow while free from tension or under compression. Crimping is preferably effected in an obstruction crimping apparatus. Specified water-insoluble dyestuffs are dispersed acetate dyestuffs, dispersed vat dyestuffs and vat-acid leuco compounds of vat dyestuffs, and as water-soluble developable derivatives of dyestuffs, there may be employed esters of leuco-vat dyestuffs and easily splittable esters of azo dyestuffs or of aminoanthraquinones containing hydroxy groups reactive with polyvalent acids. To the impregnating dyestuff liquor may be added swelling agents, dyestuff carriers, lubricants and textile assistants having an anti-static action and thickening agents, several of which are specified. The steamed tow may finally be washed and dried, a second crimping operation, if desired, being effected on the tow either before or after drying. Spin-dyed filaments may be treated. Examples are given. Specification 327,394, [Class 15 (ii)], is referred to.