ELECTROPHOTOGRAPHIC DEVICE

摘要

PURPOSE:To improve the contrast of a picture, printing resistance and heat resistance by superposing an AC voltage to the developing bias of a developing machine and fixing a distance between the sleeve of the developing machine and a photosensitive body at a prescribed range value. CONSTITUTION:The developing machine 12, a charger 14, etc. are arranged on the periphery of the photosensitive body 11 consisting of amorphous silicon as a main component. The sleeve 16 of the magnetic roll 13 of the developing machine 12 is arranged so as to be separated from the photosensitive body 11 by 0.2-1mm and a developing bias 18 to which an AC voltage is superposed is applied to the sleeve 16. The superposition of the AC voltage to the developing bias makes it possible to increase the efficiency of the triboelectrification of a developer and increase the quantity of the charge of a toner.