| 摘要 |
The image quality obtainable by an electrographic copying process in which an electrostatic latent image formed by imagewise exposure of a uniformly charged photoconductive layer, or otherwise, is developed with a toner can be improved if the latent image comprises discrete charge bearing zones, preferably formed by a supplementary exposure through a half-tone screen, and if additionally the toner is electrically conductive either intrinsically or as a result of electrical break-down. In this manner, the maximum density obtainable in a copy can be increased and the contrast decreased sufficiently to allow good reproduction of both continuous tone and high contrast images. |
