Process for spinning particulate dispersions

Claim 1

A PROCESS FOR PREPARING SELF-SUPPORTING FIBERS, FILAMENTS, YARNS, AND FILMS OF THERMOPLASTIC POLYMERIC MATERIALS WHICH COMPRISES FORMING AN AQUEOUS DISPERSION OF PARTICLES OF A THERMOPLASTIC MATERIAL COMPRISING A WATER INSOLUBLE COPOLYMER OF A MIXTURE OF COPOLYMERIZABLE MONOETHYLENICALLY UNSATURATED MONOMERS COMPRISING AT LEAST ONE POLAR COMPOUND SELECTED FROM THE GROUP CONSISTING OF VINYL ACETATE, ACRYLONITRILE, METHACRYLONITRILE, ACRYLAMIDE, METHACRYLAMIDE, ESTERS OF ACRYLIC ACID, AND ESTERS OF METHACRYLIC ACID, SAID MATERIAL HAVING AN APPARENT SECOND ORDER TRANSITION TEMPERATURE OF AT LEAST ABOUT 25*C., BEING DISPERSED WITH AN EMULSIFYING AGENT IN STABLE AQUEOUS DISPERSION AT PARTICLE SIZES BELOW ABOUT TWO MICRONS, SAID PARTICLES CONSTITUTING AT LEAST 20% BY WEIGHT OF THE DISPERSION, PASSING SAID DISPERSION AS A STREAM THROUGH AN ORIFICE DIRECTLY INTO AN AQUEOUS COAGULATING BATH CONTAINING 5% TO 50% BY WEIGHT OF AN ALKALINE MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES AND QUATERNARY AMMONIUM HYDROXIDES AND HAVING A PH OF AT LEAST 8, WHEREBY A SHAPED PRODUCT IS FORMED IN THE BATH BY COAGULATION OF SAID STREAM, DRAWING THE SHAPED PRODUCT AT A SUBSTANTIALLY CONSTANT SPEED THROUGH, AND THEN OUT OF, THE BATH, WASHING THE SHAPED PRODUCT, AND HEATING IT IN A ZONE HELD AT A TEMPERATURE OF AT LEAST 60*C. FOR A TIME SUFFICIENT TO (1) BRING THE PRODUCT ABOVE ITS APPARENT SECOND ORDER TRANSITION TEMPERATURE BUT BELOW THE TEMPERATURE AT WHICH CHEMICAL DECOMPOSITION OCCURS, (2) DRY SAID PRODUCT, AND (3) CAUSE COALESCENCE OF PARTICLES THEREIN.