An image forming apparatus includes a control unit for controlling a
plurality of fixing units independently of one another regardless of a
state of an image forming unit, and a receiving unit for receiving image
forming requests, and has a control sequence, in which when not all of a
recording medium material, a recording medium state, environment, and
image data satisfy predetermined conditions, at least one of the
plurality of fixing units are caused to operate, and a control sequence,
in which when it is detected that an image forming request, for which all
of the plurality of fixing units are required, is received by the
receiving unit, each currently unused fixing unit is caused to operate.
Accordingly, it is possible to realize high productivity even when there
exist fixing units not driven due to the recording medium physical
properties, recording medium state, environment, image data, or the like.