Method for molding and coating materials and articles by internal pressure

Claim 1

A MOLDING METHOD COMPRISING THE STEPS OF INSERTING INTO A MOLD CHAMBER A BODY COMPRISING COMMINUTED WOOD MATERIAL HAVING A POROUS STRUCTURE AND CONTAINING A THERMOSETTING BINDER AND HAVING ON AT LEAST A PART OF ITS OUTER SURFACE AT LEAST ONE COATING SUBSTANTIALLY CONSISTING OF PLASTIC AND HAVING A GAS PERMEABILITY LOWER THAN THAT OF THE INSIDE OF SAID BODY, SAID COATING CONTAINING VOLATILE CONSTITUENTS CAPABLE OF DEVELOPING A GAS PRESSURE WHEN SAID COATING IS HEATED, CLOSING SAID MOLD CHAMBER AND THEREBY EXERTING A PRESSURE UPON THE OUTER SIDE OF SAID COATED BODY, HEATING SAID COATED BODY WITHIN SAID MOLD, AND EXERTING AN INTERNAL GAS PRESSURE WITHIN SAID BODY SO AS TO EXERT A UNIFORM COUNTERPRESSURE WITHIN AN AREA OF SAID BODY ADJACENT TO SAID COATING, SAID COUNTERPRESSURE EXCEEDING THE VAPOR PRESSURE OF SAID VOLATILE CONSTITUENTS AND THUS SUBSTANTIALLY PREVENTING THE DEVELOPMENT OF SAID GAS PRESSURE, AND THEREBY BONDING SAID COATING TO SAID BODY.