JPS56116046A - Two-color electrophotographic method - Google Patents

Abstract

PURPOSE:To make constitution simple and lower the cost by selectively using ordinary two colors and reversed two colors which charge primarily and secondarily so as to assume mutually opposite polarities for a photoreceptor having the 1st and 2nd photoconductive layers. CONSTITUTION:A photoreceptor P laminated with the 1st photoconductive layer 2 which has sensitivity to specific colored light, for example, a red color, and the 2nd layer 3 allowing the transmission of said light is used on a conductive substrate 1, and positive and negative voltages are successively applied on the surface of the photoreceptor to charge the same primarily and secondarily, whereby electrical double layers are formed in the photoreceptor. On the other hand, the similar photoreceptor P is used, and the process of primarily charging the surface of the photoreceptor to positive, secondarily charging the same to the negative polarity opposite from that of the primary charging while irradiating the two-color images to be copied, and irradiating the specific colored light over the entire surface, thereby process forming the latent images of mutually opposite polarities is selectively used. Thereby, either of two colors is selectively reproduced by using the same photoreceptor and the same toners with the simple constitution.