GB817724A - Process for the production of artificial fibres of regenerated zein - Google Patents

Abstract

Artificial fibres comprised of regenerated zein which has been spun by a one-bath process as described in U.S.A. Specification 2,478,248, from an aqueous zein solution containing formaldehyde, to form fibres which, in the form of tow, have optionally been precured by allowing the tow to remain, while still wet with coagulating solution, for 1/2 to 3 hours in a chamber containing air of high humidity and at 80-100 DEG F., are treated by stretching the tow by 50 to 300 per cent or more, impregnating it while still under tension with a solution containing 3-10 per cent of sulphuric acid, 3-10 per cent formaldehyde and at least 90 per cent saturated with sodium chloride, at 110-140 DEG F., and then relaxing the tension, maintaining the tow at a temperature of 110-140 DEG F. for 1/2 to 2 hours in a chamber containing air having a humidity of at least 90 per cent and washing the tow and thereafter, if desired, drying the tow and baking it at an elevated temperature, e.g. 300 DEG F. In the example, a tow of regenerated fibres prepared as described in U.S.A. Specification 2,478,248 up to the washing and stretching stages, is passed, while being maintained under sufficient tension to maintain the stretch, back and forth between two rollers dipping into an aqueous saturated sodium chloride solution containing 3.5 per cent by weight formaldehyde and 5.0 per cent by weight sulphuric acid. The tow is then mangled to 100 per cent solution retention, the tension on the tow relieved, and the tow passed through a chamber of air at 120 DEG F. and 100 per cent R.H for a residence time of 2 hours. The tow is finally washed for 27 minutes in water at 80 DEG F., dried at 150 DEG F. for 60 minutes and baked at 300 DEG F. for 60 minutes.