Patent ID: 7356289

Claim:
An image forming apparatus comprising: (a) a photoreceptor which forms an electrostatic latent image thereon; (b) a developing device which applies a developing bias voltage obtained by superimposing an AC bias voltage onto a DC bias voltage to the photoreceptor, and develops the latent image on the photoreceptor with a two-component developer to form a toner image; (c) a controller for controlling the developing bias voltage; (d) a transfer device for transferring the toner image onto a transfer material; (e) a fixing device for fixing the toner image on the transfer material; and (f) a cleaning device for collecting and cleaning a toner on a surface of the photoreceptor, wherein the image forming apparatus provides a toner forced discharge mode for forming a toner image for forced discharge in a first image formation area provided in a non-image formation area other than a second image formation area on the photoreceptor to forcibly discharge a toner from the developing device, and when the toner forced discharge mode is selected, an AC bias voltage at a frequency lower than that in the second image formation area is applied to the first image formation area for forced discharge to develop a latent image for forced discharge, thereby a toner image for forced discharge is formed, and a toner of the toner image for forced discharge is collected by the cleaning device.