Patent ID: 7239827

Claim:
An image forming apparatus comprising: at least one image carrier that carries an electrostatic latent image; an electrostatic latent image forming device that forms an electrostatic latent image on a surface of the image carrier; a plurality of developing devices, each having a developing agent carrier, each of the plurality of developing devices applying the developing agent on the surface of the image carrier on which the electrostatic latent image is formed by the electrostatic latent image forming device such that a developing agent image is formed on the surface of the image carrier; a transfer device that transfers the developing agent image on the surface of the image carrier formed by each of the plurality of developing devices onto a transfer target medium, a part of the developing agent transferred to the transfer target medium being reversely transferred from the transfer target medium to the image carrier and being collected on a surface of the developing agent carrier; a reversely transferred developing agent amount estimating device that estimates each amount of the reversely transferred developing agent on the surface of the developing agent carrier; and a reversely transferred developing agent removing device that removes the collected reversely transferred developing agent from the surface of the developing agent carrier when the amount of the reversely transferred developing agent estimated by the reversely transferred developing agent removing device exceeds a predetermined value.