| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a thin film from being formed on a form when a toner cartridge whose toner is for a nonmagnetic single-component development system is replaced. <P>SOLUTION: A developing bias potential is so set (step ST3) so that the potential of a developing toner is -400 V for a predetermined time after cartridge replacement (step ST1) and an electrostatic charging bias voltage is so set (step ST4) so that the potential on the surface of a photosensitive drum is -700 V; and the developing bias voltage is varied (step ST8) the predetermined time later (step ST7) so that the potential of the developing roller is -300 V and also varied so that the potential of the photosensitive drum surface is -800 V. <P>COPYRIGHT: (C)2004,JPO |
