GB1331751A - Manufacture of textile filaments from synthetic organic polymer films - Google Patents

Abstract

1331751 Film fibrillation ERNEST SCRAGG & SONS Ltd 1 Sept 1971 [5 Sept 1970 1 Dec 1970] 42635/70 and 56959/70 Heading B5B In a process for the production of filaments from fibre of synthetic organic polymer material by fibrillation a film is operated upon by a profiling element which produces lines, zones or areas of weakness in the film by pressure contact when the film is in a heat softened condition and at a temperature between a first temperature where the crystals of the polymer material have begun to melt and a second higher temperature at which substantially all of the crystals have melted and the film is then fibrillated along the lines of weakness to form filaments. The film may be fed to the profiling element at a temperature within or below the above range the profiling element itself being maintained at the required temperature. Where the film material is polypropylene the preferred temperature range is 160-165‹ C. Preferred apparatus for carrying out the profiling operation comprises a pair of co-acting rollers between which the film passes in pressure contact, at least one of the rollers being profiled to produce the desired lines, zones or area of weakness of the film. The other roller may be a heated plain backing-up roller. The profiled roller surface 10 suitably has a square thread profile formed with alternate ribs 11 and grooves 12, the corners of the grooves being substantially 90 degrees angles (Fig. 1) or slightly less than 90 degrees angles (Fig. 2, not shown).