Process for the production of crimpable regenerated cellulose fibers and yarn

Claim 1

A PROCESS FOR THE PRODUCTION OF REGENERATED CELLULOSE FIBERS COMPRISING ESSENTIALLY EXTRUDING THROUGH ELONGATED SPINNERET OPENINGS HAVING LONG AXES AT LEAST ABOUT 8 TIMES LONGER THAN THE SHORT AXES INTO A COAGULATING AND REGENERATING BATH CONTAINING FROM ABOUT 6.5 TO ABOUT 10% SULFURIC ACID, FROM ABOUT 12 TO ABOUT 23% SODIUM SULFATE AND AT LEAST ABOUT 3% ZINC SULFATE, PAIRS OF STREAMS OF VISCOSES IN SIDE-BY-SIDE RELATIONSHIP, THE FIRST OF SAID VISCOSES CONTAINING A SMALL AMOUNT OF A COAGULATION MODIFIER AND HAVING A SALT INDEX OF AT LEAST ABOUT 5, THE SECOND OF SAID VISCOSES CONTAINING NO COAGULATION MODIFIER AND HAVING A SALT INDEX AT LEAST ABOUT 3 UNITS LOWER THAN THE SALT INDEX OF SAID FIRST VISCOSE, COAGULATING AND REGENERATING SAID PAIRS OF STREAMS OF VISCOSES TO FORM INTEGRAL REGENERATED CELLULOSE FIBERS CONTAINING TWO LONGITUDINAL RIBBON-LIKE COMPONENTS DISPOSED SIDE-BYSIDE, AND STRETCHING THE INTEGRAL FIBERS AT LEAST ABOUT 40% DURING COAGULATION AND REGENERATION.