| 摘要 |
<p>1,126,759. Artificial fibres and filaments. MITSUI PETROCHEMICAL INDUSTRIES Ltd. 25 Nov., 1966 [27 Nov., 1965; 15 Nov., 1966], No. 52959/66; Heading B5B. [Also in Division D1] Split fibrous material having uniformly sized meshes is produced by stretching a tape of thermoplastic organic synthetic polymer longitudinally at a stretch ratio of 3 : 1 to 10 : 1, and slitting the tape so that a plurality of sets of slits are obtained parallel to the direction of stretch, each slit in a set being spaced substantially equidistant from the next, and each set being staggered a small distance transversely from the preceding set such that the sets overlap in the longitudinal direction, and stretching the slit strip in a direction transverse to. the longitudinal direction of the strip to obtain a netlike structure of relatively thick fiaments of a size between 15 and 50 deniers, and relatively thin filaments of a size appreciably thinner than the thick filaments but between 3 and 15 deniers. An apparatus for carrying out the process comprises two pairs of nip rolls with a slitting member mounted between them which rotates in the same direction as the moving tape and at a greater speed, the surface of the slitting member having a plurality of sets of slitting blades disposed parallel to the circumferential direction and spaced substantially equidistantly from each other in the axial direction, each set being disposed such that the " file " of the blacks (defined) is successively staggered a small distance transversely of that of the preceding set, the sets being in spaced relationship to each other in the circumferential direction. Several types of slitting members are described. In one embodiment the split fibre may be crimped by passing the stretched tape through at least one pair of heat embossing rolls before slitting as above, and then heat shrinking the split fibre to impart crimps. Yarn-like material may be produced by spreading out the split fibre, cutting it at intervals along its length, and thereafter twisting each portion of the cut split fibre. Polyolefins such as polyethylene or polypropylene, are the preferred polymeric material used.</p> |
