Electrophotographic selenium layer prodn. on conductive substrate - by vacuum evaporation above glass transition temp. and tempering

摘要

Prodn. of an electrophotographic layer on a (coated) electrically conductive substrate involves vacuum evapn. of Se at a substrate temp. above the Tg of Se, followed by tempering. Pure Se is evaporated at a substrate temp. of 30-55 degrees C and a condensn. rate of 0.5-2.0 mu m/min. and tempered 30 min. to 2 hr. at 60-75 degrees C in an oven, pref. a continuous-heating oven or an air-circulating oven. In an example, Se was evaporated onto an (Al) drum at 40 degrees C and 10-5 torr at a rate of 1 mu m/min, the tempered for 90 min. at 65 degrees C. A good quality film with strong adhesion, entirely free from crystallisation, and improved dark decya and residual potential was obtd. It gave copies with excellent contrast.