| 摘要 |
PURPOSE:To achieve color image formation with excellent contrast by using amorphous silicon for a photosensitive drum on which latent images differing in polarity are formed by development with different-color developers differing in electric polarity. CONSTITUTION:Connection between a charger 2 and power sources 38 and 39 are chnged over by a switch 37 to form latent images, differing in electric polarity, on a photosensitive drum 1, and the latent image are developed by developing devices 4 or 5 which corresponds to the polarity of the latent image with different polarites of black or red and the like, thus forming a color image. This drum 1 is made of amorphous silicon containing 0.01% O2 to obtain sufficient electrostatic contrast to the positive, negative and positive polarities, so an excellent color image with the excellent contrast of each color is formed. |
