| 摘要 |
PURPOSE:To prevent fogging on a copy by holding the conductive substrate of a photoreceptor at a prescribed potential, supplying a developer, charged with the opposite polarity to the potential of said photoreceptor conductive substrate while having 10<12>-10<13>OMEGA.cm, to a photoreceptor surface after supplying different-polarity charges to the photoreceptor surface as optical information, and then preventing toner from separating and scattering from the drum surface. CONSTITUTION:The substrate 3 of a drum 1 is grounded through a bias power source 21. Thus, the substrate 3 is held at a potential with the opposite polarity to the discharging polarity of a primary charger 4, namely, the charging polarity of a developer 9 and usual processes such as laser irradiation 5, development 6, etc., starting at primary charging 4 are performed to form a developed image and a final copy is obtained through a transferring stage 12. The bias power source 21 is connected to the drum substrate 3 through a slip ring provided around a drum rotating shaft, and the drum substrate 3 is insulated electrically from a copying machine body by making a drum flange of an insulator. On a surface of the drum 1 which coresponds to a light part, charges having the opposite polarity to the toner and some surface potential are held, improving the attracting force of the toner 1 for the drum. |
