| 摘要 |
PROBLEM TO BE SOLVED: To attain sufficient image density and to maintain such stable image quality that surface staining and a residual image are reduced. SOLUTION: This device 4 is equipped with a developing roller 10 arranged by being faced to a latent image carrier 2 and set for supplying toner to the carrier 2 at the faced part, an electrical conductive toner replenishment roller 12 which is arranged to abut on the circumferential surface of the roller 10 and whose circumferential surface is relatively moved at a part where it abuts on the roller 10 and a power source 18 impressing a bias voltage between the rollers 10 and 12. By electric power generated by the bias voltage, the toner excessively supplied to the roller 10 from the roller 12 is thinlayered on the roller 10 by a triboelectrification means 14. Then, the electrostatic charge of the thin-layered toner is made uniform. Besides, a means regulating the quantity of the toner on the roller 12 is not provided at an upperstream part in the rotating direction of the roller 12 than the abutting part. |
