| 摘要 |
PURPOSE:To make a boundary between the image area and the blank area of a transfer material sharp by previously imparting the same specified potential to a 1st area and a 2nd area on an image carrier corresponding to the blank area by an electrifying member. CONSTITUTION:Transfer bias impressed on a transfer roller 108A is -4kV when the transfer material P exists at a transfer position, and +2kV is impressed as cleaning bias in order to transfer toner from the roller 108A to a photoreceptor 102 while the transfer material P does not exist at the transfer position. The center of electrifying bias to form the blank area on the trailing edge side of the transfer material P and the center of the electrifying bias to prevent the occurrence of memory in the case of impressing the cleaning bias on the roller 108A are the same -300V. Therefore, in the area on the image carrier 102 where the toner is removed from the roller 108A and the area of the image carrier 102 corresponding to the blank area, the center of bias previously impressed on the electrifying member 103 while passing a primary electrifying position is -300V and the center of bias need not be switched. |
