| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus that maintains a stable amount of a specific component of a developer in a developing device, even when a new developer is charged in the developing device and when a new developing device is attached to an apparatus body.SOLUTION: According to a first condition in which a development housing 80 including an unused developing roller 83 is attached to an apparatus body, or a second condition in which an unused developer is retained in the development housing 80, a consumption condition changing unit 94 causes a photoreceptor drum 321 to consume a specific component in the developer from the developing roller 83. The consumption condition changing unit 94 changes a developing bias during non-developing operation, or the rotation speed ratio of the developing roller 83 to the photoreceptor drum 321, so as to have the specific component to be consumed at the photoreceptor drum 321 side. The specific component represented by an external additive is suppressed to be excessively retained in the development housing 80. |
