| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus where the occurrence and growth of black spots (BS) can be suppressed. <P>SOLUTION: The image forming apparatus 1 includes: a photoreceptor drum 20; a charger 30; an exposure 40; a development device 50 of a one component development system; a transferring device 60; and a cleaning blade 70. The one component developer includes: toner; a first external additive having the same charging property as that of the toner; and a second external additive having a charging property reverse to that of the toner. The apparatus includes: an electrically conductive member 80 contacted with the photoreceptor drum 20 at the position on the downstream of the cleaning blade 70 and also on the upstream of the charger 30; and a power source 83 applying bias voltage to the electrically conductive member 80. The direction of the bias voltage to ba applied is reverse to that of the charging polarity in the charger 30 based on the surface potential in the photoreceptor drum 20 at a position directly before the electrically conductive member 80, and also, it is higher than the discharge starting voltage between the photoreceptor drum 20 and the electrically conductive member 80 by an absolute value. <P>COPYRIGHT: (C)2008,JPO&INPIT |
