| 摘要 |
PROBLEM TO BE SOLVED: To provide an image-forming device capable of exerting control so that an optimum transfer-voltage is applied according to the type of a transfer material, the amount of images during consecutive both-sided printing, and etc., and capable of preventing a density irregularity caused by a difference in electrification potential. SOLUTION: A voltage Vdm is applied after electrification is started and then the electrification potential of a photoreceptor drum reaches -400 V, and from the point that is before one rotation is made prior to the start of transfer to recording paper (at a time where the photoreceptor drum has made 1.5 rotations after the start of the electrification). Thus, the electrification potential is decreased in advance to one that is approximate to electrification potential to be obtained after transfer to the recording paper. Then, from a point where the recording paper has reached between the photoreceptor drum and a transfer roller, a voltage Vsmp is applied and transfer to the recording paper is carried out. This enables restraining density irregularities on the same recording paper and maintain uniform density, even with a halftone image. |
