GB443076A - Improvements in the manufacture of staple fibres - Google Patents

Abstract

Staple fibre from viscose is obtained by a continuous operation wherein filaments from a large number of spinning nozzles are combined to form a thick bundle and led vertically upwards and downwards a number of times over a series of rolls or similar deviating members, the thick bundle while travelling upwards being freed from tension, washed and, if desired, desulphurized, bleached, and again washed, the treatment liquid flowing in counter current, and the bundle is then passed to drying devices such as heated rollers, and to cutting devices. The filament bundle may be treated with dilute ammonia or soda solution during the first washing process so as to neutralize acids. In order to free the bundle from tension during the liquid treatment, the rollers may be rotated at different speeds or brake rods or plates may be provided. The filament bundle may be cut to staple fibre while still containing a considerable amount of moisture. The bundle may be curled by passing it while damp between grooved drying plates or rods arranged in the form of a grid. The plates may be heated electrically, by gas flames, or by heated air. They may be on endless bands and moved in the direction of the filaments. As shown in Fig. 2, a large number of filaments 5 are combined together by rollers 17 and guides 18 to form a thick bundle 21 which passes up and down between rollers 22-37. The upper rollers are driven at a lower peripheral speed than the lower rollers so that the filaments are free from tension during the upward run, and under tension when moving downwards. Washing liquid is applied to the upwardly moving filaments from spraying nozzles 24, 38, 39, 40. Dilute soda solution is applied from the nozzles 41, and water from nozzle 42. The filament bundle passes to a drying drum 44 and then <PICT:0443076/IV/1> <PICT:0443076/IV/2> <PICT:0443076/IV/3> cutting device 51. As shown in Fig. 3, the curling device consists of drying plates 53, 54 with interengaged grooves. As shown in Fig. between grooved drying plates 49, 50 travelling on endless bands in the direction of the bundle. The curled filament bundle then reaches a 4, closely arranged rods in grid form between which the bundle passes in a sinuous path are used as the curling device.