Patent ID: 7274900
Filing Date: 2007-09-25
Classification: G03G

Abstract:
1. A color image forming apparatus that has a plurality of image carrying bodies and forms a color image, comprising: first image forming means for forming toner images of chromatic colors other than black with a first laser exposure; primary transfer means for transferring the toner images, which are formed by the first image forming means, to an intermediate transfer member; secondary transfer means for transferring the toner images, which are transferred to the intermediate transfer member by the primary transfer means, to a transfer medium; second image forming means for forming a black toner image with a second laser exposure, wherein a sphericity of the black toner for forming the black toner image is at most 1.2; and direct transfer means for directly transferring the black toner image, which is formed by the second image forming means, to the transfer medium on which the toner images are transferred by the secondary transfer means, wherein the first image forming means includes an image carrying body that carries an electrostatic latent image on a surface thereof, exposure means for exposing the image carrying body on the basis of color image data and forming an electrostatic latent image, and a developing device of a plurality of different chromatic toners, which develops the electrostatic latent image that is formed by the exposure means, wherein a development bias is lowered below an image area potential so as to prevent further development in a case where a non-developed electrostatic latent image remains on the image carrying body of the first image forming means.