GB1317557A - Preparation of coloured synthetic fibres from a fibrillated film - Google Patents

Abstract

1317557 Film fibrillation SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV 22 May 1970 [26 June 1969] 32363/69 Heading B5B [Also in Division D1] Coloured fibres are made from a molecularlyorientable organic polymer, optionally blended with a homopolymer, copolymer or interpolymer of styrene by forming the polymer into a film which has a plurality of longitudinal grooves disposed in close but spaced apart relationship, stretching the film longitudinally at a stretch ratio and at a temperature such that the film web is molecularly oriented in the longitudinal direction to facilitate splitting, and if necessary, fibrillated to produce filaments, said process, when performed using the blend of the molecularly orientable organic polymer and styrene polymer, including having at least one dyestuff or colouring material compatible with the blend incorporated in the film or applied to the film or the resultant fibres; when the molecularly orientable organic polymer is used in the absence of the styrene polymer at least one dyestuff or colouring material is incorporated in the film, the extruded film being profiled using a profiling element. Thus the film may be extruded through a profiling die or the extruded film may be brought into pressure contact with a profiling roller, e.g. by bringing the extruded coloured film into pressure contact with the element. The molecularly-orientable polymer may be polyethylene or polypropylene. The profiling element may be maintained at a temperature either below or above the crystalline melting point of the film. The styrene polymer may be a terpolymer of acrylonitrile, butadiene and styrene, a tapered 2- block copolymer of styrene and butadiene, or an elastomer-modified polystyrene. The blend of orientable polymer and styrene polymer may contain 5 to 50%, preferably 10 to 30% of styrene polymer. The colouring material used may be organic or inorganic.