| 摘要 |
PROBLEM TO BE SOLVED: To provide a reversal development color image forming device not generating a printing fog. SOLUTION: A paper carrying belt 22 is circulated counterclockwise to carry paper sheets. Four photoreceptor drums 20a, 20b, 20c and 20d are rotated clockwise in contact states with the front surface of the belt 22. Electrifying brushes for initialization 32 uniformly electrify the peripheries of the photoreceptor drums 20 at high negative potentials, writing heads 35 form electrostatic latent images on the charged peripheries of the drums 20 and developing rollers 34 transfer toner 36 to the low potential parts of the electrostatic latent images, to attain reversal development. Respective transfer brushes 26 transfer toner images on the respective drums 20 to the paper sheets, in such a manner that at least a transfer current It4 on the most downstream side out of transfer currents It1, It2, It3 and It4 is set maximum and applied to the paper sheets with the paper carrying belt 22. An electrifying voltage Vc4 applied to the drum 20b by the electrifying brush for the initialization 32d on the most downstream side is made high to '-50V', to keep a potential by electrification for initializing the drum >='-500V'. |
