| 摘要 |
1,199,724. Extruding sheets; composite films; fibrillated products. O.-B. RASMUSSEN. 31 Oct., 1967 [5 Oct., 1966], No. 44525/66. Headings B5A and B5B. [Also in Division Dl] A sheet-like extrusion product consists of transverse lamellae 43 of a first polymeric material and longitudinal lamellµ 45 of a second polymeric material, the lamella 45 being restricted to the surface region of the sheet. If desired a third polymeric material 44, which may be foamed, is introduced into the interstices between lamellµ 43 and 45. The sheet can be used as a substitute for a non-woven fabric by fibrillating the lamellµ 45 either by drawing the sheet or by using a two-component compound for the second material one of which components can be dissolved out. Apparatus suitable for producing the above sheet material comprises a fixed extruder head provided with a row of slots, slots 9 being fed via channels 6 and 8 with the first polymeric material, whilst slots 11 are fed via channel 7 with the third polymeric material. Located in front of the slots is a transversely reciprocable frame made up of a pair of combs 12 having oppositely directed teeth 15 and 16, each of which is provided with a slot 17 through which the second polymeric material is extruded. The composite sheet passes through the combs and is taken off by ' conventional means. In a second embodiment, see Fig. 3 (not shown), the set-up is similar to that above except that each comb carries a double row of teeth, the teeth in the row furthest from the slots 9 and 11 being aligned with the spaces between the teeth in the row nearest said slots. In a third embodiment in which a tube is formed (see Fig. 4, not shown) the slots 9 and 11 are located in a circle whilst the teeth are carried by annular combs rotatable or oscillatable relative to the slots. In a first example the first polymeric material is nylon, the third polythene, and the second a mixture of polythene and nylon. After extrusion and drawing the polythene is washed out to leave a fabric having the characteristics of a woven textile. The components of the second material may be derived from sources separate from those for the first and third materials or may be tapped from those sources. In another example the third material may be foamed polythene or foamed polystyrene. |
