The process of electrostatic photocopying is essentially an optoelectronic process in which the latent image is an electrostatic image consisting of electrostatic charge. The charging, developing and transferring processes are based on the principle of electrostatic attraction. Affordable. Since the electrostatic latent image is formed by the discharge of the photoconductive layer under light, the charge discharge is formed on the charge film layer, so the Carlson electrostatic copying method has the following requirements for the photosensitive drum: has a very high dark resistivity. This kind of photosensitive drum in the case of no light, the surface once the existence of electricity, can save these charges for a long time; and in the case of light, the photosensitive drum resistivity should be quickly reduced, that is, So that the drum surface charge quickly released and disappeared. The photosensitive drum used in the Calson electrostatic photocopying method is mainly composed of selenium and selenium alloy, zinc oxide, organic photoconductive material, etc., and is usually coated or deposited on a conductive substrate (such as an aluminum plate or other metal plate) Photoconductive material. Its structure is above the light guide layer, the following is the conductive substrate.
Charging is to make the drum in the dark, and in a polar electric field, so that the surface evenly with a certain polarity and the amount of static charge, that is, a certain surface potential of the process, this process is actually photosensitive Drum of the sensitization process, so that the original does not have the photosensitive drum has a better sensitivity. The charging process is only prepared for the photosensitive drum to accept the image information, is not dependent on the original image information pre-process, but this is the formation of electrostatic latent image on the photosensitive drum prerequisite and foundation.