Dichromatic image reproduction method

Abstract

Abstract PURPOSE: To obtain dichromatic image of high quality, by making the abrasive force to the latent image carrier surface of a second magnetic brush developing apparatus weaker than that of a first apparatus, in dichromatic image reproduction method by electrostatic copying. CONSTITUTION: A photosensitive drum 1 is, for example, negatively charged for the part corresponding to the red color of the original, and positively charged for the part corresponding to the black color, and dichromatic copy image is obtained by developing with negatively charged red color toner 6a in a first developing apparatus 6 and positively charged black color toner 7a in a second developing apparatus 7. In this machine, the abrasive force to the drum 1 of the second developing apparatus 7 is made weaker than that of the first developing apparatus 6. This means is achieved by the method, for instance, of rotating the developing sleeve 6a of the first developing apparatus 6 in the same direction and the sleeve 7a of the second developing apparatus 7 in the reverse direction, with respect to the rotating direction of the photosensitive drum 1. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Kunihiko Ikeda
• 👤 Shuichi Karasawa
• 👤 Fuyuhiko Matsumoto

Bibliographic Details