GB1116925A - Dyed textile yarn and fabrics prepared therefrom - Google Patents

Abstract

In the production of a dyed composite yarn, fibres of a hydrophobic synthetic polymer, e.g. acrylonitrile homopolymers and copolymers, polyolefins such as polypropylene, polyamides, polyesters such as polyethylene terephthalate, are modified to improve their dyeability as by incorporation of alkylacrylamide polymers such as poly - N - alkylacrylamides, acrylic ester polymers including polyethylacrylate and polymethylmethacrylate, polyvinylpyridines poly - (vinylpyrrolidones), polyvinyl acetals, e.g. polyvinylbutyral, epoxy resins e.g. epichlorohydrinsulphide or epichlorohydrin - bis - phenol condensates, polyalkylimines, polycarbonates, polyoxyalkenes, divalent metal salts or aliphatic carboxylic acids and metal sulphonates, and are also treated e.g. by heating, drafting and cooling without relaxing, to render them heat-shrinkable. The resultant fibres are dyeable at low temperatures, i.e. less than 160 DEG F, and are capable of at least 20% linear shrinkage on heating to elevated temperatures e.g. 250 - 300 DEG F. These fibres are combined, as by fibre or sliver blending, with "heat-stable" fibres, e.g. cotton, mohair, wool, viscose, acrylonitrile homopolymers and copolymers, linear cyclohexane - 1, 4 - dimethanol terephthalate polyesters, polyethylene terephthalate, modacrylics, (stabilised as necessary) and formed into yarn. The fibres (or only the shrinkable component) are dyed (the shrinkable fibres at the low temperature) separately or when combined, by cationic or basic, disperse, or premetallized dyes (which may include assistants and levelling agents such as non-ionic surfactants and phosphate compounds) before or after yarn formation, and are dried at a temperature of 180 - 220 DEG F. Before or after the yarn is made into knitted, woven and/or pile fabric, it is heated at the elevated temperature to cause differential shrinkage of the constituent fibres and consequent bulked effects in the yarn and/or fabric.