Process for manufacturing macromolecular cellulose fiber

Claim 1

IN THE MANUFACTURE OF MACROMOLECULAR CELLULOSE FIBER WITH D.P. ABOVE 500, THE PROCESS CONSISTING IN STEEPING CELLULOSE-CONTAINING MATERIALS HAVING MACROMOLECULAR CELLULOSE OF NOT LESS THAN 800 D.P. IN AN ALKALI BATH THE CONCENTRATION OF WHICH VARIES INVERSELY AS THE D.P. OF THE CELLULOSE WITHIN THE RANGE OF 17% FOR 800 D.P. TO 13% FOR 1400 D.P., PRESSING THE ALKALI CELLULOSE THUS FORMED SO THAT THE RATIO OF THE PRESS WEIGHT OF THE MATERIAL TO THE WEIGHT OF THE ORIGINAL CELLULOSE VARIES INVERSELY WITH THE D.P. OF THE CELLULOSE WITHIN THE RATIOS OF SUBSTANTIALLY 2.8 TIMES THE CELLULOSE WEIGHT TO 2.4 TIMES THE CELLULOSE THUS OBSHREDDING THE UNAGED ALKALI CELLULOSE THUS OBTAINED IN AN ATMOSPHERE OF INERT GAS, XANTHATING THE UNAGED SHREDDED ALKALI CELLLOSE IN THE PRESENCE THERETO A QUANTITY OF CARBON BISULPHIDE TO NOT LESS THAN 45% OF THE ALKALI CELLULOSE IN THE PRESENCE OF AN INERT GAS AT A PRESSURE VARYING DIRECTLY AS THE D.P. OF THE CELLULOSE WITHIN THE RANGE OF SUBSTANTIALLY 2 ATMOSPHERES FOR 800 D.P. TO OVER 12 ATMOSPHERES FOR 1400 D.P., AND DISSOLVING THE SODIUM CELLULOSE XANTHOGENATE THUS OBTAINED IN WATER.