| 摘要 |
PURPOSE: To obtain an excellent image over a long period, by preventing the deterioration of developer while reducing the load imparted to the developer in the vicinity of the developer layer thickness control member. CONSTITUTION: This developing device provided with a developer carrier 1 in which a magnet member 3 is fixedly set while furnished with plural electric field generating means 4 inside a hollow cylindrical sleeve 2 possible of rotating, is constituted that the developer layer thickness control member 5 is arranged to face oppositely on the upstream side of an effective developing area M of the developer carrier 1, the electrostatic latent image is made visual by allowing non-magnetic toner of the two component developer G to soar to the electrostatic latent image formed on the latent image carrier 6. Then, radial direction magnetic flux density B of of magnetic field generating means 4 in a region opposite to the developer layer thickness control member 5 is set >=5mT, <=35mT. Moreover, the developer feed/separation member 7 is arranged on the upstream side of the developer layer thickness control member 5 across a gap 8 being <=3.5mm corresponding to the developer carrier 1. |
