Production of conducting layers upon electrical insulating materials

Claim 1

A PROCESS FOR PRODUCING AN ORGANIC ELECTRICALLY INSULATING MATERIAL COATED WITH A LAYER OF AN ELECTRICAL CONDUCTOR WHICH COMPRISES APPLYING TO THE SMOOTH SURFACE OF A SYNTHETIC ELECTRICALLY INSULATING ORGANIC PLASTIC MATERIAL HAVING AT LEAST ONE SMOOTH SURFACE A SLURRY OF A FINELY DIVIDED ELECTRICAL CONDUCTOR IN A VOLATILE INERT LIQUID, SAID SLURRY BEING SUBSTANTIALLY FREE FROM NONVOLATILE ORGANIC MATERIALS AND SAID VOLATILE LIQUID BEING WITHOUT SUBSTANTIAL SWELLING ACTION UPON SAID PLASTIC MATERIAL, EVAPORATING THE GREATER PART OF SAID VALATILE LIQUID AND, PRIOR TO COMPLETION OF EVAPORATION THEREOF AND WHILE THERE IS STILL SUFFICIENT LIQUID TO ADHERE SAID ELECTRICAL CONDUCTOR TO SAID PLASTIC MATERIAL, SIMULTANEOUSLY APPLYING HEAT AND PRESSURE TO THE COATED SURFACE TO COMPLETE EVAPORATION OF SAID VOLATILE LIQUID AND TO CAUSE THE INDIVIDUAL PARTICLES OF CONDUCTING MATERIAL TO COHERENT AND TO BECOME AT LEAST PARTIALLY EMBEDDED IN THE UNDERLYING INSULATING MATERIAL AND WITHOUT SUBSTANTIALLY EFFECTING THE ELECTRICAL PROPERTIES OF THE SURFACE OF SAID MATERIAL.