Electrophotographic developer made from cross-linked silicone intermediate resin

Abstract

Abstract THE METHOD OF PREPARING A STABLE, DRY ELECTROPHOTOGRAPHIC DEVELOPER COMPOSITION CONCENTRATE CONSISTS ESSENTIALLY OF ADMIXING AND SUSPENDING ABOUT ONE PART BY WEIGHT OF A SILICONE INTERMEDIATE RESIN WITH FROM ABOUT ONE TO FIVE PARTS BY WEIGHT OF A CROSS-LINKING PROMOTING CATALYST IN AN AROMATIC CARRIER LIQUID AND HEATING THE ADMIXTURE AT A TEMPERATURE OF FROM ABOUT 50 TO 100*C. FOR A PERIOD OF ABOUT 1 TO 24 HOURS; ADMIXING THE HEATED ADMIXTURE WITH FROM ABOUT 0.5 TO 4 PARTS BY WEIGHT OF AN INSOLUBLE SOLID PIGMENT PER PART OF RESIN PLUS CATALYST PRESENT (SOLVENT-FREE BASIS); MILLING THE RESIN-CATALYST AND PIGMENT MIXTURE TOGETHER IN A GRINDING MILL FOR AT LEAST ABOUT 8 HOURS; AND EVAPORATING THE SOLVENT FROM THE SOMILLED ADMIXTURE. THE DRY CONCENTRATE IS MADE INTO A LIQUID CONCENTRATE BY MILLING THE DRY SOLIDS FOR FROM ABOUT 8 TO 24 HOURS WITH SUFFICIENT ORGANIC CARRIER LIQUID, SUCH AS A LIQUID ALIPHATIC HYDROCARBON, TO PROVIDE A SUITABLE GRINDING SLURRY VISCOSITY. THIS MILLED LIQUID CONCENTRATE IS DILUTED FURTHER WITH CARRIER LIQUID TO PROVIDE THE PROPER CONCENTRATION OF CATALYST PER LITER OF COMPOSITION AS WELL AS AN ELECTRICAL CONDUCTIVITY WITHIN THE DESIRED RANGE AND THE SODILUTED MIXTURE IS A WORKING ELECTROPHOTOGRAPHIC DEVELOPER COMPOSITION.

Inventors

• 👤 Louis J Sciambi

Bibliographic Details