Manufacture of cadmium sulfide photoconductive cell bodies

Claim 1

A PROCESS FOR THE ACTIVATION OF A CADMIUM SULFIDE PHOTOCONDUCTIVE CELL BODY BY THE INTRODUCTION WITHIN THE CRYSTAL LATTICE STRUCTURE THEREOF OF ACTIVATOR ATOMS OF AT LEAST TWO METALS IN CONCENTRATIONS OF FROM A HUNDREDTH OF A PERCENT TO ONE PERCENT, ATOMS OF ONE OF SAID METALS BEING CAPABLE OF BEING INTRODUCED WITHIN SAID LATTICE STRUCTURE AT A LOWER TEMPERATURE THAN ATOMS OF THE OTHER OF SAID METALS, ATOMS OF SAID ONE METAL WHEN INTRODUCED TENDING TO PREVENT THE ENTRANCE INTO SAID LATTICE STRUCTURE OF ATOMS OF THE OTHER OF SAID METALS, SAID PROCESS COMPRISING THE STEPS OF PREPARING A FIRST PULVERULENT MIXTURE OF CADMIUM SULPHIDE AND SAID OTHER METAL IN POWDERED FORM, SAID OTHER METAL BEING HOMOGENEOUSLY DISPERSED IN SAID FIRST MIXTURE IN A CONCENTRATION EQUAL TO THAT OF THE REQUIRED CONCENTRATION OF SAID OTHER METAL IN THE TREATED CELL BODY AND THE MASS OF SAID FIRST MIXTURE BEING ABOUT ONE HUNDRED TIMES THE MASS OF SAID CELL BODY, IMMERSING SAID CELL BODY IN SAID FIRST PULVERULENT MIXTURE, APPLYING TO SAID FIRST MIXTURE WITH SAID CELL BODY IMMERSED THEREIN A PRESSURE OF FROM TEN TO SEVERAL TENS OF KILOGRAMS PER SQUARE CENTIMETER, HEATING SAID IMMERSED BODY AND FIRST MIXTURE TO A TEMPERATURE APPROACHING 660*C., REMOVING SAID CELL BODY FROM SAID FIRST MIXTURE, PREPARING A SECOND PULVERULENT MIXTURE OF CADMIUM SULPHIDE AND OF SAID ONE METAL IN POWDERED FORM, SAID ONE METAL BEING HOMOGENEOUSLY DISPERSED IN SAID SECOND MIXTURE IN A CONCENTRATION EQUAL TO THAT OF THE REQUIRED CONCENTRATION OF SAID ONE METAL IN THE TREATED CELL BODY, IMMERSING SAID CELL BODY IN SAID SECOND PULVERLENT MIXTURE, APPLYING TO SAID SECOND MIXTURE WITH SAID CELL BODY THEREIN A PRESSURE OF FROM TEN TO SEVERAL TENS OF KILOGRAMS PER SQUARE CENTIMETER, HEATING SAID IMMERSED BODY AND SAID SECOND MIXTURE TO A TEMPERATURE BETWEEN 400* C. AND 600*C. AND NO GREATER THAN IS NECESSARY TO ACCOMPLISH THERMAL DIFFUSION IN THE SOLID PHASE OF ATOMS OF SAID ONE METAL INTO SAID CELL BODY, REMOVING SAID CELL BODY FROM SAID LAST-NAMED PULVERULENT MIXTURE, PAINTING ELECTRODES ON SAID CELL BODY, AND PASSING BETWEEN SAID ELECTRODES FOR ABOUT FORTY-EIGHT HOURS WHILE SAID CELL BODY IS UNDER ILLUMINATION AN ELECTRIC CURRENT SUFFICIENT TO DISSIPATE IN SAID CELL BODY A POWER OF ABOUT ONE MILLIWATT PER SQUARE MILLIMETER OF SENSITIVE AREA OF SAID CELL.