GB1330463A - Manufacture of non-woven materials - Google Patents

Abstract

1330463 Forming tubular mats; bonded fibre fabrics IMPERIAL CHEMICAL INDUSTRIES Ltd 16 Sept 1970 [1 Oct 1969] 48196/69 Headings D1N and D1R Continuous synthetic filaments 10N, 10S are projected by at least 2 forwarding means 38N, 38S, situated inside a hollow non-rotating tubular collecting member, (22, Fig. 1, not shown) into the surface of said member, there being angular motion between said forwarding means and said tubular member, such that the mean distance between them preferably remains constant, to form a tubular web. Preferably the filaments have a core of nylon 66 and a sheath of copolymerised nylon 66 (70%) and nylon 6, so that autogenous bonding of the web may be carried out by means of high pressure steam alternatively the web may be impregnated with a binder applied as a solid, liquid or solution, followed by heating. The continuous filaments are ejected by compressed air supplied by tube 46 which is rigid apart from flexible piece 50 and is embedded in plates 40, 48. Outer tube 42 is rotated, and transmits torque to swash plate 40 which is prevented from rotating by tube 46. The plane of plate 40 therefore processes so that the filaments cover the whole collector surface without net relative angular rotation between the forwarding means 38N, 38S and the sources of supply of the filaments (14) averaged over a 360‹ sweep of the forwarding means. A swash plate with 4 forwarding means is described. Large diameter collectors may be provided with a swash plate mounted on an arm which rotates about the axis of the collector. In the embodiment of Fig. 7 stationary plate 54 supports air ejectors having fixed portions 56 and rotatable portions 58 which end in portions-61 aligned at an angle to the tube axis, rotation being caused by a toothed wheel or ribbed belt. The hollow tubular member may be composed of vertically arranged foraminous or impervious belts which are driven so that a continuously descending surface is produced which removes the web. In a modification the tubular member comprises parallel rods, some of which move inwardly and downwardly then outwardly and upwardly. Alternatively the tubular member may be a stationary sheet down which the web is pulled by rolls. A web of polyamide filaments adheres to the tubular member by virtue of electrostatic charge which they pick up. Steam or moisture may be injected to reduce the adhesion. Suction may be applied to a foraminous tubular member. The cross section of the tubular member may become increasingly elliptical as its lower end is approached and a driven bowed roll set under the tubular member, so that the tubular web is collected as a "lay-flat" doubled web. Alternatively the web may be slit by cutting, shearing or thermal means. The web may be wound up on a roll together with a layer of tissue paper (34).