| 摘要 |
<p>1,169,661. Laminated non-woven fabrics. HERCULES Inc. 23 Feb., 1968 [1 March, 1967], No. 8999/68. Heading B5N. A non-woven fabric is produced by passing superposed webs 1-5 of oriented plastics film through a needling device 16 which produces splits in the films and breaks up some of the resulting strands to form filamentary portions which are forced through the different layers, and causing at least the ends of the filamentary portions near the surface of the superposed webs to curl so as to interlock those portions. Preferably, the webs are oriented in directions along the web and across the web alternately and at least some of them are composite, being formed, e.g. by simultaneous extrusion, from two plastics materials, such as polypropylenes of different molecular weight distribution, having different shrink characteristics when heated, in which case, the curling of the filamentary portions is brought about by heating the webs either in the vicinity of the needling machine or in an oven 19. Feed rollers 17, 20 maintain a suitable tension during heating along the webs and a tenter mechanism may perform the same function across them. Other suitable plastics are polyolefins, polyesters, polyamides, polyethers and polyvinyls.</p> |
