HIGH PERFORMANCE CRIMPED RAYON STAPLE FIBRE

摘要

1342805 Crimped rayon fibres ITT INDUSTRIES Inc 14 Oct 1971 [20 Oct 1970] 47837/71 Heading B5B Crimped rayon filaments and staple fibres are prepared from a viscose spinning solution having a viscosity between 80 and 140 ball fall seconds, a salt index of between 2À5 and 6 and containing a mixture of viscose modifiers. The viscose solution is spun at a temperature of 35 to 45‹ C. into a coagulating bath containing from 4 to 6% by weight sulphuric acid, from 1 to 6% ZnSO 4 and from 10 to 20% Na 2 SO 4 . The filaments, coagulated but incompletely regenerated in this bath, are, whilst still substantially soluble in dilute alkali, stretched by up to 120% of their original length and, during stretching, their regeneration is started by passing them through a hot dilute acid bath. After regeneration is complete, the filaments are cut, if staple fibres are required, or the tension is relaxed to develop the crimp. The resulting filaments or fibres are washed and disulphurized. Modifiers disclosed are dimethylamine and polyethylene glycol.