Patent ID: 7672604

Claim:
An image forming apparatus, which visualizes latent images formed successively on an image carrier and develops the latent images by depositing a plurality of toners of different colors on the image carrier, comprising: a plurality of developing devices, each comprising a toner conveyance member that is cylindrically shaped and configured to convey said toner to a region opposing said image carrier by means of a conveyance electric field created by applying a multi-phase voltage to a plurality of electrodes arranged lengthwise in parallel at a predetermined interval along a length of the cylindrically shaped toner conveyance member; and a voltage application device configured to apply said voltage to the electrodes of said toner conveyance member of each of the developing devices, said voltage having an average potential value between a potential of image portions of said latent image and a potential of non-image portions of said latent image, wherein, taking Vm to be the average potential of the voltage applied to the electrodes of the toner conveyance member of the mth developing device (m=1˜m) in the sequence of depositing toner on said image carrier, the relationship |Vm|<|Vm+1| is established between the average potential values of the voltages applied to the electrodes of the toner conveyance members of the respective developing devices.