| 摘要 |
PURPOSE:To obtain a high-grade image regardless of kinds of toners by coating ceramics contg. Si and/or Ge atoms on the surface of a toner holding body and a control member for forming a thinner layer. CONSTITUTION:The ceramics contg. the Si and/or Ge atoms is coated on at least the surface of a developing roller 55 as the toner holding body and an elastic blade 57 as the control member for forming the thinner layer. The above- mentioned ceramics has a small coefft. of friction and, therefore, the wear of the roller 55 and the blade 57 by the friction thereof is decreased and the good image is obtd. stably even if the developing device is operated for a long period of time. Since the above-mentioned ceramics can be changed in the electric conductivity and electrical conductiveness over a wide range, the ground fogging in the case of using a toner having low electrostatic chargeability and the degradation in density in the case of using the toner having the high electrostatic chargeability are prevented by selecting the compsn. of the ceramics so as to meet the electrostatic chargeability of the toner. The high-grade image is thus obtd. regardless of the kinds of the toners. |
