| 摘要 |
PURPOSE:To keep the potential of surface of a photoreceptor constant, by pre- exposure in a short wave length light, in an electrophotographic method using a photoreceptor coated with isolation layer. CONSTITUTION:An electrostatic image is formed with processes of uniform charge and exposure simultaneous discharge to a photoreceptor consisting of a conductive layer 1, photo conductive layer 2 and isolation layer 3. In this case, while some sheets of copying are repeated it is observed that the potential of surface of a photoreceptor is increased, but it is not desirable from the standpoint that a constant quality is needed of copies. Ahead the uniform charge, the pre-exposure in a short wave length of 300-450nm is applied to the photoreceptor, then light is absorbed at upper part of the photo conductive layer 2, about several thousands Angstrom in distance from the boundary with the layer 3, conductive electrons are generated, and the increase in the surface potential can be cancelled through the recombination with holes stored at the part. |
