| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus which is able to restrict caking of paper powder.SOLUTION: An image forming apparatus comprises: a first image forming unit having a conveyance belt 73, a photoreceptor drum 51K, a charger 52K, and a recovery roller 57K and provided to form a monochrome image in a monochrome print mode; a second image forming unit having photoreceptor drums 51Y, 51M, and 51C, chargers 52Y, 52M, and 52C, and recovery rollers 57Y, 57M, and 57C, and provided to form a multi-color image in a multi-color print mode; and a control device 500 that controls biases applied to the chargers 52 and the recovery rollers 57. In the monochrome print mode, the control device 500 applies a first charging bias smaller in an absolute value than in the multi-color print mode to the chargers 52Y, 52M, and 52C, applies a first bias of reverse polarity of the polarity of charged developer to the recovery roller 57K, and applies a second bias of the same polarity as the charged developer to the recovery rollers 57Y, 57M, and 57C. |
