GB1141666A - Electrophotographic printing element - Google Patents

Abstract

1,141,666. Electrophotography. A. B. DICK CO. 30 Aug., 1967 [31 Aug., 1966]. No. 39646/67. Heading H1K. An electrophotographic element comprises a conductive flexible substrate having thereon a coating comprising a binder, a photoconductor, an activator and a diphenyl methane compound of formula:- wherein R 1 , R 3 and R 4 are H, alkyl, alkenyl, cycloalkyl, aralkyl, aryl or substituted aryl; R 2 is alkyl, alkenyl, cycloalkyl, aralkyl, aryl or substituted aryl; R 5 is H, alkyl, alkenyl, aralkenyl, cycloalkyl, or cycloalkenyl and R 6 and R 7 are H, alkyl, alkoxy, alkenyl, cycloalkyl, aryl, aryloxy, substituted aryl, halogen, carboxy or cyano. The preferred substrate is paper whilst the diphenyl methane compound may be 4,4<SP>1 </SP>- tetramethyl diaminophenyl methane. ZnO may be used as the photoconductor whilst the binder is preferably a styrenated alkyd resin, polyvinyl acetate, chlorinated rubber, methylmethacrylate, a silicone resin, or copoly butadiene-styrene. Sensitizing dyes such as bromophenol blue, acridine orange, fluorescein, dibromofluorescein and euchrysine may be used. The coating composition may be made by first milling together all the components other than the binder, adding the binder and milling further.