| 摘要 |
PURPOSE:To obtain an image having an uniform shade without increasing a density on the rear edge of the flat part of the image by adopting a noncontact developing system using a one component nonmagnetic toner thin layer formed on a toner layer carrier as a developing means for a color except the first color, and impressing a pulse bias as a developing bias. CONSTITUTION:First, the surface, of a drum-like photosensitive body 1 is electrified by an electrifier 2. An electrostatic latent image is formed on the photosensitive body 1 by an exposing means 3, and developed by the developing means 4 to form a first toner image. Next, the photosensitive body 1 is reelectrified by an electrifier 5, and the same potential state of a first exposing part as that of a circumference is obtained. Then, a second electrostatic latent image is formed on the photosensitive body 1 by an exposing means 6, and developed by a developing means 7 to form a second toner image on the photosensitive body 1. Then, a multicolor image is transferred on a recording medium on a carrying path 8 by a transfer electrifier 9 in one transfer. In the developing means 7, the nonmagnetic one component toner is used. A toner layer on a developing roller 21 is opposite to the photosensitive body 1 without noncontact, they are moved at almost same speed, and a pulse bias obtained by superimposing an AC on a DC on a power source 27, is impressed as a developing bias, when development is carried out. |
