| 摘要 |
[Problem] To provide an image forming device that can suppress contamination of a charging device and dielectric breakdown for photosensitive bodies by maintaining a prescribed range for a ratio of metal particles in recovered toner. [Solution] The image forming device, which forms a color image by sequentially superimposing color toner images formed on photosensitive drums (1) onto an intermediate transfer belt (5), is provided with a plurality of photosensitive drums (1), a charging device (4) that comes into contact with and charges each of the photosensitive drums (1), a developing device (21) for making toner that includes metal particles, which are polishing particles, adhere and developing a latent image, and a cleaning device (3) for eliminating residual toner from the surface of the photosensitive drums (1). The image forming device is provided with a primary transfer bias control unit (53) wherein a primary transfer bias outside of the image forming time on the photosensitive drums (1) is switched to the same polarity or the opposite polarity as the charge of the toner according to an average printing rate for the previous prescribed number of sheets for each color. |
