| 摘要 |
PURPOSE:To offer a developing device capable of obtaining a high quality image by preventing picture lines from becoming thick while maintaining gradation. CONSTITUTION:A developing roller 1 on which an electroconductive area 21 and an insulating area 22 are formed by a knurling process is so arranged that it faces the surface of a photosensitive drum 3, on which an electrostatic latent image is formed, with a 100mum interval. The insulating area 22 is rubbed by a toner supplying roller 8. Consequently, in this area, positive charges are held and negatively-charged toner 7 is carried. Reversal development is carried out by applying a pulse voltage to this developing roller 1. |
