Patent ID: 8290384

Claim:
An image forming device comprising: a plurality of image retainers that respectively retain images of respective colors formed on respective surfaces while rotating; a plurality of image forming sections that respectively form toner images with charged toners of the respective colors on the respective surfaces of the plurality of image retainers; a transfer accepting body that circulates on a course passing through the plurality of image retainers sequentially and has a surface to which the toner images on the respective image retainers are transferred electrostatically; a plurality of transfer members that respectively face the plurality of image retainers across the transfer accepting body interposed in between, are given a charge that provides the image retainers with a potential difference having a polarity opposite to a polarity of the charged toners, and transfer the toner images formed on the plurality of image retainers to the transfer accepting body; a first charge applying section that applies the charge to at least one of the transfer members and switches, according to an instruction, between a first mode of applying the charge to all the plurality of transfer members and a second mode of applying the charge to a part of the plurality of transfer members; and a second charge applying section that applies, when the charge is applied in the second mode but not in the first mode, a charge having the same polarity as the polarity of the charged toners, and having a charge value selected to cause the charge on the transfer accepting body to settle on a convergence potential before image formation, to the surface of the transfer accepting body, at an applying point located upstream from points where the toner images are transferred to the transfer accepting body in a moving direction of the transfer accepting body, wherein the convergence potential is a maximum potential value which is acceptable by the transfer accepting body, and which has a same polarity as a polarity of the charged toners.