| 摘要 |
PURPOSE:To eliminate a void arising in a peripheral part of a solid image by installing an electrode plate, which attracts toner included in developer to the surface of the developer, in the upstream part of a developing area in the developer feeding direction. CONSTITUTION:The developing area 25 is formed in the part where a developing roller 18 faces a photosensitive drum 24. Development is performed in the developing area 25 by bringing the bristle edge of a magnetic brush 20 in contact with the surface of the photosensitive drum 24. In addition, the electrode plate 20 which attracts toner included in the developer forming the magnetic brush 20 to the surface of the magnetic brush 20 is installed in the upstream part of the developing area 25 in a magnetic brush feeding direction. A bias voltage of polarity opposite from the electrified polarity of the toner is applied by a power supply circuit 31 to the electrode plate 20. Therefore, a void occurring in the peripheral part of the solid image is eliminated. |
