| 摘要 |
PURPOSE:To obtain a sharp image at all times by coating ceramics contg. atoms of at least one kind selected from Al, B and C on at least the surface of a toner holding body. CONSTITUTION:The ceramics contg. the atoms of at least one kind selected from Al, B and C is coated on at least the surface of a developing roller 55 as the toner holding body. The above-mentioned ceramics has high hardness and excellent wear resistance and, therefore, the wear of the toner holding body by the friction thereof is decreased and the driving torque of a developing device is decreased. In addition, the above-mentioned ceramics has an excellent insulating characteristic and is capable of sufficiently electrostatically charging a toner which is hardly chargeable and, therefore, the high-grade image having no ground fogging is obtd. even in the case of using the toner having low electrostatic chargeability. The always sharp image is thus obtd. according to this developing device without degrading the image density and without generating the thinning of characters and the ground fogging. |
