Process of drying hydrogel microspheres

Claim 1

A PROCESS FOR PRODUCING A GEL POWDER CONSISTING ESSENTIALLY OF SPHERICAL PARTICLES BELOW 1 MILLIMETER IN DIAMETER AND ADAPTED FOR USE IN PROCESSES INVOLVING THE SUSPENSION OF POWDERED GEL PARTICLES IN A GESEOUS STREAM WHICH COMPRISES FORMING A HYDROSOL OF THE DESIRED GEL FORMING MATERIAL, EMULSIFYING SAID SOL IN A WATER IMMISCIBLE LIQUID AS A DISPERSED PHASE OF FINE HYDROSOL DROPLETS CAPABLE OF FORMING PARTICLES OF A DIAMETER SPECIFIED, MAINTAINING SAID EMULSION UNTIL THE SOL DROPLETS FROM THE EMULSION, ING THE HYDROGEL DROPLETS FROM THE EMULSION, FIRST FREEZING AND THEREAFTER THAWING SAID DROPLETS TO REMOVE A LARGE PORTION OF THE WATER THEREFROM WOTHOUT EFFECTING ANY SUBSTANTIAL AGGLOMERATION OF THE INDIVIDUAL HYDROGEL PARTICLES INTO LARGER MASSES AND THEREAFTER FURTHER DRYING SAID MATERIAL TO FORM A DRY GEL POWDER OF THE CHARACTER MENTIONED WITHOUT THE NECESSITY OF FURTHE MOLDING, EXTRUDING OR GRINDING.