an electrographic printing apparatus comprises a photoconductive member surrounded by a charging unit , an optical print head , a developing unit , a transfer unit , a cleaning unit , and an erasing unit arranged in sequence about the photoconductive member . paper travels along a planar path across the top of the photoconductive member and the developed image is transferred to the underside of the paper . in a preferred embodiment , the photoconductive member comprises a vertically mounted photoconductive belt . by providing a separate and independent cleaning unit , the electrographic printing apparatus is capable of producing one sheet of copy material per revolution of the belt .