| 摘要 |
PURPOSE:To obtain an excellent photosensitive body having no fog by using a photosensitive body of a three layer structure constituted fundamentally of a conductive layer, a photoconductive layer and an insulating layer. CONSTITUTION:A photosensitive drum 1 is electrostatically charged uniformly, and simultaneously, a negative image is exposed by a negative latent image forming means 3. The drum 1 is charged by a destaticizing AC corona charger 5, and its surface potential is set to about zero. Thereafter, a light is irradiated uniformly by a full surface exposing lamp 7. By this light irradiation, a charge remains behind in parts A, B. As for the part A and the same B, the potential rises in accordance with each charge quantity, and the part A and the part B rise to the highest V3 and the intermediate potential of V4, respectively. On the other hand, the part C remains as V2 which is almost equal to zero. In this way, a composite electrostatic latent image consisting of a potential shown by V3 corresponding to an image part of a negative latent image, a potential shown by V4 corresponding to a background part, and three potentials shown by V2 corresponding to an image part of a positive picture is formed on the drum 1. |
