GB1306940A - Loopy yarn - Google Patents

Abstract

1306940 Spinning and finishing yarns COURTAULDS Ltd 15 July 1970 [16 July 1969] 35747/69 Headings D1F and D1W Loopy, hand-knitting yarn is made by forming a sheath/core yarn of which the fibres forming the sheath have a greater shrinkage capacity than the fibres forming the core, and heating the yarn e.g. by hot air at a temperature of at least 150‹C, in relaxed condition to effect differential shrinkage between the two yarn components whereby the core fibres project through the sheath fibres as loops which are held at their points of generation by sheath fibres. The fibres may be staple or continuous and may all be flame-resistant. The core may be of glass, regenerated cellulose or acrylic fibres which have been textured e.g. by subjection to a turbulent fluid stream, and the sheath fibres of an acetone-soluble copolymer of acrylonitrile and vinylidene chloride and/or vinyl chloride. The core may be twisted and/or in the final form of the yarn be twistless according to the required openness of the loops, sheath and core components may be differently coloured and the composite yarn may be doubled, prior to hot relaxing, with a balancing twist.