Process for shaped cellulose article prepared from a solution containing cellulose dissolved in a tertiary amine N-oxide solvent

DETAILED DESCRIPTION What is claimed: 1.
A process for making a cellulose fiber or film which comprises extruding a solution containing a cellulose dissolved in a tertiary amine N-oxide solvent containing a nonsolvent for cellulose to shape the solution as a film or filament, stretching the film or filament while still a solution to orient the molecules and develop improved physical properties in said cellulose fiber or film, and precipitating the cellulose from said solution to set the properties thereof without additional drawing.
2.
The process of claim 1 wherein the product is a fiber.
3.
The process of claim 1 wherein the product is a film.
4.
The process of claim 1 wherein the stretching is at a spin-stretch ratio of at least 3.
5.
The process of claim 1 wherein said nonsolvent for cellulose is water.
6.
A process for making a cellulose fiber having a wet elongation about equal to its conditioned elongation, a tenacity of at least about 1.
4 gpd and a wet modulus of at least about 7 gpd at 5% elongation which process comprises spinning through a spinneret a solution containing cellulose dissolved in a solvent which contains a tertiary amine N-oxide solvent for cellulose and an organic non-solvent for cellulose which is miscible with the tertiary amine N-oxide, pulling the resulting filament as it emerges from said spinneret at a 3 to 1 spin-stretch ratio to orient the molecules while the cellulose remains in solution, and then into a non-solvent for cellulose which precipitates the cellulose from the spun solution.




Description:
It has been proposed before to make shaped cellulose articles such as fibers and films by a process wherein cellulose or a derivative of cellulose is dissolved in a solvent, the resulting solution is shaped and the cellulose is recovered from the solution as a solid shaped article.
Such processes include the viscose process and cuprammonium process for making rayon.
Rayon, however, is not entirely satisfactory for making some fabrics normally made with cotton because relatively poor mechanical properties, high swelling, and a sharp increase in wet elongation under low stress exclude its use where shape retention after washing is important