| 摘要 |
PURPOSE:To improve the quality of an image without disturbing a toner image by impressing auxiliary bias with which electrostatic field in a direction where the toner image is electrostatically attracted on an auxiliary magnet member is weakened. CONSTITUTION:This device is an image forming device in which two component type developer consisting of toner and magnetic carrier whose density is <=4.0g/cm<2> is used in a developing means at least at second and succeeding stages, and auxiliary bias Vb is impressed on the auxiliary magnet member 6 installed at the back part of the developing nip part of the developing means 3b at the second and succeeding stages in order to weaken the electrostatic field in the direction where the toner image already formed by the developing means 3a at a preceding stage is electrostatically attracted. Thus, the deterioration of the image quality based on carry-over phenomenon is evaded and the excellent image is obtained without disturbing the toner image already formed. |
