| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing roller flexible enough to suppress deterioration of toner with time and difficult to produce eternal deformation. SOLUTION: The developing roller has an axial core body, an elastic body layer, and a coating layer covering the elastic layer as a surface layer. Asker-C hardness on the surface of the coating layer is between 40°and 85°. The coating layer has a thickness of 15-5,000 nm. Martens hardness H1(N/mm<SP>2</SP>) on the surface of the developing roller, martens hardness H2(N/mm<SP>2</SP>) of the elastic body layer, and the film thickness d(mm) of the coating layer satisfy the relation of following expression (1): 400≤(H1-H2)/d≤2000 (1). COPYRIGHT: (C)2009,JPO&INPIT |
