Patent ID: 7756453

Claim:
A color printing apparatus, comprising: a plurality of photosensitive drums corresponding to a respective color; a transfer belt which is aligned with the plurality of photosensitive drums; a printing unit which prints using at least two modes, one being a single color mode and another being a multi-color mode; an attaching/detaching mechanism which attaches the transfer belt to the photosensitive drums used in the multi-color in an attached position and detaches the transfer belt from the photosensitive drums which are used only in the multi-color mode in a detached position; and a controller which controls the attaching/detaching mechanism based on a number of consecutive pages in the single color mode when a corresponding job includes both the single color mode and the multi-color mode such that the attaching/detaching mechanism is in the detached position during the single color mode when the number of pages in the single color mode is at least one of greater than or equal to a predetermined number of consecutive single color mode pages, and the attaching/detaching mechanism is in the attached position during the single color mode when the number of pages in the single color mode is less than the predetermined number of consecutive single color mode pages.