Process for preparing homogeneously partially polymerized particles of thermosetting material

Claim 1

A PROCESS FOR PREPARING HOMOGENEOUSLY PARTIALLY POLYMERIZED PARTICLES OF PLASTIC MATERIAL SUITABLE FOR STORING PRIOR TO MOLDING AND COMPLETE POLYMERIZATION COMPRISING PREPARING THE MATERIAL FOR A COMPOSITION SETTING UNDER THE ACTION OF HEAT, GIVING THE MATERIAL A PRELIMINARY HEAT TREATMENT TO PARTIAL POLYMERIZATION AND COOLING SAID MATERIAL SUBSTANTIALLY INSTANTANEOUSLY TO HARDENED CONDITION OF PREDETERMINED DESIRED THINNESS AND BRITTLENESS PREPARING THE MATERIAL TO BE FRACTURED BY A HAMMER BLOW AGAINST FREELY SUSPENDED PIECES, IMMEDIATELY REDUCING SAID THIN MATERIAL TO PIECES OF DESIRED SMALL SIZE, MAINTAINING SAID MATERIAL BELOW A TEMPERATURE AT WHICH THERE IS ANY SUBSTANTIAL POLYMERIZATION, THEN INTRODUCING SAID THIN PIECES AS FREELY-MOVING UNITS INTO THE PATH OF A FAST-MOVING SURFACE AND SUBJECTING SAID PIECES WHILE FREELY MOVING TO FRACTURE BY SAID FAST-MOVING SURFACE, PROJECTING THE RESULTING FRACTURED PARTICLES FROM SAID SURFACE FREELY THROUGH THE AIR AGAINST ANOTHER SURFACE CAUSING FURTHER FRACTURE OF SAID PARTICLES TO SMALLER SIZE AS SAID PARTICLES BREAK THEMSELVES AGAINST SAID SECOND SURFACE SO THAT SAID FRACTURING IS DUE TO THE INERTIA OF THE PIECES AND PARTI-