Color image forming apparatus and method

摘要

A first negative or positive latent electrostatic image is formed on a latent image bearing body with a first writing device, and developed with a monochromatic toner. A second latent image of the type different than the first latent image is formed by a second writing device after setting the background voltage of the second image to have an absolute value larger than the first image, and then developed with one or two color toners selected from three color toners of respective multi-color developing units. A plurality of multi-color toner images may be formed in respective rotation cycles of the latent image bearing body. A monochromatic toner image may be formed in the same rotation cycle as one of the multi-color toner images. Finally, a plurality of toner images thus produced are transferred onto a recording sheet at once after polarities of the plurality of toner images have been arranged into the same polarity.