Manufacture of casting powder granules

Claim 1

A PROCESS FOR PRODUCING SUBSTANTIALLY DRY, FULLY COLLOIDED, NONPOROUS NITROCELLULOSE CASTING POWDER GRANULES WHICH COMPRISES FORMING A SOLUTION BY DISSOLVING NITROCELLULOSE HAVING A DEGREE OF SUBSTITUTION CORRESPONDING TO A NITROGEN CONTENT OF AT LEAST 11.3% BY WEIGHT IN WATERSOLUBLE ALKOXY ALCOHOL, PREFORMING THE RESULTING SOLUTION INTO SHAPED BODIES, INTRODUCING THE SHAPED BODIES OF PREFORMED SOLUTION INTO A WATER BATH CONTAINING AT THE POINT OF INITIAL CONTACT NOT MORE THAN 90% BY WEIGHT OF WATERMISCIBLE ALKOXY ALCOHOL TO SHOCK-GEL SAID SHAPED BODIES BY RAPIDLY FORMING A TOUGH ENVELOPE OF GELLED NITROCELLULOSE ON THE SURFACES OF SAID BODIES SO THAT SAID BODIES RETAIN THEIR PREFORMED SHAPE, LEACHING THE RESULTING SHOCK-GELLED BODIES IN THE PRESENCE OF ADDITIONAL WATER UNTIL SUBSTANTIALLY ALL OF THE ALKOXY ALCOHOL THEREIN HAS BEEN REPLACED BY WATER TO FORM WATER-LOGGED GEL PARTICLES, SUBJECTING THE WATER-LOGGED GEL PARTICLE TO SYNERESIS IN A FREEZING ATMOSPHERE TO CAUSE WATER TO EXUDE IN LIQUID FORM FROM THE WATER-LOGGED GEL PARTICLES AND TO FREEZE ON THE OUTER SURFACE OF SAID PARTICLES UNTIL SUBSTANTIALLY LESS THAN 1% BY WEIGHT OF WATER REMAINS IN THE NITROCELLULOSE PARTICLES, AND THEREAFTER REMOVING THE FROZEN WATER FROM THE OUTSIDE OF THE PARTICLES.