GB1015548A - Improvements in or relating to the spinning of high molecular weight polyamide filaments - Google Patents

Abstract

1,015,548. Melt-spinning polyamides. BRITISH NYLON SPINNERS Ltd. May 4, 1964 [May 25, 1963], No. 20970/63. Heading B5B. In a process of melt-spinning high molecular weight synthetic linear polyamides into filaments wherein the filaments after solidication are treated with steam, and wound up, the filaments, after solidification, and before the steam treatment, are forwarded by forwarding means at a controlled linear speed which is equal to or differs by less than 4% from, the linear speed of winding-up. The forwarding means may be a driven godet or driven nip rolls, and the linear speed of the godet or rolls is preferably 97% to 99¥% that of winding up. The filaments are desirably gathered into a bundle by a convergence guide, except when a row of parallel filaments are spun from a straight line of orifices, when the guide may be unnecessary. The steam treating means may be a vertical open-ended pipe, circular or rectangular in cross-section, in which an atmosphere of steam is maintained. In one embodiment, filaments of polyhexamethylene adipamide are melt-spun from melter 1, in association with pumping means and a spinneret, gathered in guide 2 and passed into the nip of rolls 3, which forward the filaments at a speed a few per cent less than the wind-up speed. The filaments are passed through steamer 4 and are wound up at 5. The filaments are cooled at 6 by a blast of cold air. The wound filaments are subsequently drawn between feed and draw rolls (not shown). The provision of the forwarding means 3 eliminates elongation of the filaments between the convergence guide and wind-up, and makes possible a higher through-put of yarn without adversely affecting yarn properties.