彩色图像的形成方法以及彩色图像的形成装置

A color image forming device for forming a toner image of a plurality of colors on a medium and improving a secondary transfer efficiency from an intermediate transfer body onto the medium; the device comprising image forming units for forming a toner image of a plurality of colors on at least one image carrier by means of a plurality of developers respectively storing different-color toners therein; in intermediate transfer body a primary transfer means for sequentially primary-transferring the toner image of the plurality of colors color by color onto the intermediate transfer body and a secondary transfer means for secondary-transferring the toner image of the plurality of colors on the intermediate transfer body onto the medium. The image forming units form the toner image of the plurality of colors on the intermediate transfer body with toner layer potentials gradually lowered in the order of transferring. A toner layer directly deposited on the intermediate transfer has a higher potential ...