GB403739A - Improvements in the manufacture of staple fibre yarns from continuous filaments - Google Patents

Abstract

403,739. Stapling continuous filaments by drawing. BRITISH CELANESE, Ltd., 22, Hanover Square, London, TAYLOR, W. I., and GIBBINS, L. B., c/o British Celanese, Ltd., Spondon, near Derby. July 4, 1932, No. 18827. [Class 120 (iii).] Yarn of a fibrous character is obtained by subjecting to a breaking operation a plurality of continuous filaments which have undergone modification in strength at intervals along their length, the resulting sliver of staple fibres being spun. The modification in strength may be effected by weakening the filaments at intervals e.g. by bruising them or by applying a solvent or softening agent at intervals or, in the case of cellulose esters, by applying saponifying agents at intervals, e.g. as in Specification 332,263, [Class 2 (ii), Cellulose &c.] ; alternatively, the filaments may be strengthened except at points at intervals by applying a size intermittently to them. The filaments are then broken by passing through two pairs of rollers, of which the second pair rotate faster than the first, and may be spun, or wound and subsequently spun, or doubled. Filaments comprising a yarn are preferably weakened in staggered formation so as to preserve the continuity of the yarn after breaking, but when several yarns are being broken together, all the filaments of any one yarn may be weakened at the same point. False twist may be applied to the broken filaments, and they may be supported by travelling bands or the like. The filaments may be treated, preferably before breaking with roughening media such as kieselguhr, talc, pumice, carborundum and emery, or with the media described in Specification 372,797, or with hygroscopic substances as in Specification 387,003. Fig. 3 shows a type of apparatus suitable for bruising the filaments 37, comprising a pair of rollers 32, 33, one having a spiral ridge 34, and the other a corresponding groove 35. Fig. 5 shows a size applying roller 45 which has a spiral groove 47, so that filaments 37 passing in contact with the roller are sized and strengthened except at certain intervals. The filaments so treated are broken between two pairs of rollers 26, 27, Fig. 2, which shows four yarns, the filaments of each of which have all been weakened at the same point. The sliver so produced is twisted and wound by the flyer 29 on the bobbin 30. Specification 403,738 also is referred to.