Method of molding and a ceramic binder formulation

Claim 1

THE METHOD OF FORMING CERAMIC BODIES IN SHEET FORM WHICH ARE SUBSTANTIALLY FREE OF PINHOLES, WHICH COMPRISES MIXING WITH A SUITABLE CERAMIC POWDER A RESINOUS BINDER COMPOSITION CONSISTING ESSENTIALLY OF A SYNTHETIC RESIN SELECTED FROM THE GROUP CONSISTING OF POLYMERS AND COPOLYMERS OF ACRYLIC AND METHACRYLIC ACIDS, ESTERS AND AMIDES, A PLASTICIZER WHICH IS SUBSTANTIALLY INCOMPATIBLE WITH SAID RESIN AND WHICH IS A LIQUID AT TEMPERATURES BELOW ABOUT 70*C., AND A MAJOR AMOUNT BY WEIGHT OF A MIXTURE OF VOLATILE ORGANIC SOLVENTS OF DIFFERENT VOLATILITIES WHICH PROVIDES FOR COMPLETE SOLVATION OF SAID SYNTHETIC RESIN AND WHICH MAY BE GRADUALLY EVAPORATED FROM SAID COMPOSITION OVER AN EXTENDED RANGE OF TEMPERATURES, SAID MIXTURE COMPRISING A MAJOR AMOUNT BY WEIGHT OF AN AROMATIC HYDROCARBON OF MEDIUM VOLATILITY, AT LEAST ABOUT 3% BY WEIGHT OF AN ESTER OF GLYCOL ETHER WHICH IS SUBSTANTIALLY LESS VOLATILE THAN SAID AROMATIC HYDROCARBON, AND AT LEAST ABOUT 5% BY WEIGHT OF AN ALIPHATIC KETONE WHICH IS SUBSTANTIALLY MORE VOLATILE THAN SAID AROMATIC HYDROCARBON, CASTING SAID MIXTURE UPON A FLAT IMPREVIOUS SURFACE AND HEATING TO EVAPORATE SAID VOLATILE SOLVENTS ANF FORM A SELFSUPPORTING SHEET, AND FIRING SAID SHEET TO BURN OFF SAID RESIN AND FORM SAID CERAMIC BODY.