| 摘要 |
PURPOSE:To totally prevent toner particles from sticking in a developer layer carrier member end area by charging electrostatically a latent image holder where a latent image to be developed is formed to the same polarity with the surface of the end area. CONSTITUTION:A nonmagnetic sleeve 15 is rotated by a driving device as shown by an arrow while a magnet 16 in a developing sleeve 13 is fixed. A developer in a container is therefore sent out of the gap between a nonmagnetic blade 17 for developer layer thickness control and the developing sleeve 13 and the end area A outside the developer coating width L of the developing sleeve 13 is coated with tetrafluoroethylene resin which provides electrostatic charging to the same polarity with toner particles. Further, the developing sleeve is applied with a minus voltage of 200-600(V). Consequently, the sleeve end area exiting from the container is charged electrostatically and negatively to repel toner particles with an electric field, thereby preventing movable toner particles from entering the sleeve end area. |
