NONMAGNETIC ONE-COMPONENT DEVELOPING DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent the dispersion of a printing density and to reduce scratches caused by the contact of a developing roller with a toner supplying roller by providing an elastic foamed body layer and a skin layer on the toner supplying roller. SOLUTION: The toner supplying roller 30 constituted of the elastic foamed body layer 30a disposed therein and the skin layer 30b as the outer peripheral part is arranged in contact with the developing roller 8. Then, the roller 30 comes into contact with the developing roller 8 with an arbitrary width, in a contact part with the roller 8 and the roller 30 has the same rotational direction as that of the developing roller 8. Further, toner supplying bias supply 11 is connected to a shaft 9a and a bias voltage whose absolute value is higher than a developing bias voltage value is applied. The developing roller 8 has a single layer constitution; a metallic shaft 8a is used as a base material and a silicone rubber as a conductive elastic member is formed on the outer periphery of the shaft 8a. Then, developing bias supply 10 is connected to the metallic shaft 8a.