Abstract: An image processing apparatus having a corona device for charging a photoreceptor to voltage levels, a developer for applying toner to the photoreceptor, and a sensor for providing a signal in relation to photoreceptor voltage for adjusting the photoreceptor voltage levels by providing signals from the sensor in response to periodic electrostatic set ups which includes developing a series of predetermined test patches on the photoreceptor, relating the signals to characteristics of the photoreceptor, adjusting the corona device for the characteristics in response to the signals, and measuring cycle down and short term photoreceptor rest recovery changes in photoreceptor voltage for use in adjusting the corona device.

Abstract: An electrophotographic imaging device including an photoconductive imaging member having a surface extending approximate to devices generating life degrading contaminants. The printing machine includes a driving unit which continues to drive the imaging member during power down and standby modes, and other critical periods, so as to extend the life of the imaging member.

Abstract: The invention is an electrophotographic imaging process comprising forming a first electrostatic latent image on an imaging surface of an electrophotographic imaging member comprising an electrophotographic insulating layer and an electrically conductive layer, developing said first electrostatic latent image with a conductive two-component developer having a conductivity between about 10.sup.-10 ohms-cm.sup.-1 and about 10.sup.-14 ohms-cm.sup.

Abstract: An electrostatographic imaging system comprising an insulating layer having an imaging surface, a conductive substrate for the insulating layer, means to form an electrostatic latent image on the imaging surface, means to form a toner image on the imaging surface in conformance to the electrostatic latent image and means to supply a variable direct current voltage to the conductive substrate. The electrostatographic imaging system may include an electrically conductive member parallel to and spaced from the imaging surface and a means to supply a variable electrical bias to the electrically conductive member in response to a change in the value of direct current voltage supplied to the conductive substrate.