GB491259A - Improvements in the manufacture of artificial filaments, yarns and similar materials - Google Patents

Abstract

Artificial filaments, yarns, and similar materials are produced and treated so as to have in addition to a flat cross-section, a denier which varies along their length. They may also be subjected to a crinkling treatment. The variation in denier may be obtained by stretching the materials to a varying extent in a regular or irregular manner during the course of their production or in an after-treatment operation. The production of filaments of flat cross-section may be effected by use of a spinning solution containing a lower proportion of cellulose derivative than that required for filaments of bulbous cross-section, e.g. less than 24 per cent of cellulose acetate in acetone. By incorporating plasticizers such as paradichlorbenzene in a cellulose organic derivative solution, filaments of flat cross-section may be obtained. Crinkling may be effected by treating the filaments with hot aqueous media such as, hot water, wet steam, or hot solutions of soap, sulphonated oils, sulphonated higher fatty acids or alcohols, or aliphatic sulphonic acids. The lustre of the materials may be altered during the crinkling treatment. Sugars or salts may be added to the aqueous liquor to preserve the lustre during the crinkling operation. The treatment with hot aqueous media may be combined with other crinkling treatments, e.g. yarns may be twisted, the twist set while the yarn is travelling, and the yarns then untwisted. The process may be applied to continuous or short length filaments. Filaments may be cut between an operation for crinkling by setting twist and removing it, and a crinkling treatment with hot aqueous media. Two or more yarns of low twist may be twisted together to a high degree, the high twist set, and the doubled yarn untwisted and left with a small degree of reverse doubling twist. The flat filaments may be of cellulose acetate or other cellulose ester or ether. Yarns may contain also other fibres or filaments of natural silk, wool, cotton, or regenerated cellulose. Staple fibre yarn may be doubled with a continuous filament yarn. Specifications 246,879, 260,312, 321,762, [all in Class 2 (ii)], 424,683, 424,752, 424,830, 424,879, 424,880, [all in Group IX], 438,584, 438,585, 438,586, 438,587; 438,655, [Group IX], 438,656; 442,073, [Group IX], 443,707, 443,773, 459,781, 464,981, [Group IX], are referred to.