| 摘要 |
PURPOSE:To prevent toner from scattering into a copying machine and to eliminate the generation of a brush mark without tailing, by providing a sealing means at the opening part of a developing device and by specifying the movement direction of a magnetic brush and the content of the toner in a developer. CONSTITUTION:The movement direction 17 of the magnetic brush of a magnetic brush developing device 1 is set opposite to the movement direction 14 of a photosensitive layer 12, and floating toner shielding walls 16a and 16c made of elastic bodies are provided at the photosensitive-layer introduction side end part and both side end parts of the opening part of the developing device. The rate of toner particles in a magnetic brush development area to magnetic carrier particles is set 20-150% greater than the amount of toner particles saturated and adsorbed to the magnetic carrier particles, thus performing development. Leakage through carriers due to excessive toner particles is prevented, and the generation of a brush mark is suppressed; and the said content results in that the generation of toner powder smoke, the dirtying of a background, the occurrence of tailing are also suppressed. |
