Patent ID: 8909082

Claim:
An image forming apparatus comprising: a rotatable image bearing member; a toner image forming portion for forming a toner image on said image bearing member; an intermediary transfer member rotatable in contact with said image bearing member; a transfer member for transferring the toner image from said image bearing member onto said intermediary transfer member at a transfer portion; an executing portion configured to execute an operation in a first mode in which a transfer voltage on the basis of a current detected when a predetermined voltage is applied to said transfer member at predetermined timing in advance of image formation is applied to said transfer member to effect the image formation, and configured to execute an operation in a second mode in which a transfer voltage is applied to said transfer member so as to provide a predetermined constant current value to effect the image formation; and a controller configured to make transition of a state of said image forming apparatus between a stand-by state in which the image formation is enabled and a sleep state in which electric power consumption is less than that in the stand-by state, wherein said controller executes the operation in the first mode in an image forming job after main switch actuation of a main assembly of said image forming apparatus and before said controller makes the transition of the state of said image forming apparatus to the sleep state; and a setting portion, operable by an operator, configured to set a productivity-priority mode in which down time reduction has priority and an image quality-priority mode in which an image quality has priority, wherein said setting portion causes said controller to execute, when the productivity-priority mode is selected, the operation in the second mode in an initial image forming job after the transition from the sleep state to the stand-by state and to execute, when the image quality-priority mode is selected, the operation in the first mode in the initial image forming job.