Patent ID: 6925270

Claim:
An image forming method comprising: forming an electrostatic image corresponding to supplied image data used for forming a toner image; forming a toner image by supplying toner to the electrostatic image so as to make the electrostatic image visible; sequentially stacking toner images on a non-external output medium having an effective image holding region of a predetermined size; when other toner images can be formed on part of the effective image holding region other than the part on which the toner images are stacked, sequentially stacking the other toner images on the other part; and when it is informed that at least one of the stacked toner images on the non-external output medium can be transferred onto an output medium, feeding an output transfer medium at a transfer position at which said at least one of the stacked toner images is transferred on the output transfer medium between the non-external output medium and a transfer output section, wherein the toner image includes one of monochrome toner images of four colors which are color-separated for outputting a color image in accordance with subtractive primaries, and wherein the same color toner is supplied during the period the non-external output medium laps and/or it rotates 360 degrees.