Process for spinning cellulose fibres and filament yarns

摘要

Process for spinning cellulose fibres and filament yarns by the dry-wet extrusion process from a solution of cellulose in a water-containing N-oxide of a tertiary amine, in particular N-methylmorpholine N-oxide, by extruding the solution through die channels having an exit-side capillary section which has a cross-section minimum dimension d within the range from 40 to 100 mu m and in which the cellulose molecules are preoriented by shearing forces, into a medium which does not precipitate the cellulose, further orienting the cellulose molecules by drawdown of the extruded solution jet in this medium in a ratio V within the range 0.5 V 3 and precipitating the cellulose from the solution jet by contacting with a precipitating medium without drawing. The process is characterised in that the cellulose solution is extruded through die channels whose length L is within the range from 200 to 800 mu m and whose capillary section has a length l within the range from 40 to 180 mu m. This short channel die process involves reduced capital investment costs for spinning dies and spinning pumps and reduced operating costs for the spinning plant.