| 摘要 |
PROBLEM TO BE SOLVED: To prevent a fringe phenomenon and to obtain a sharp image by deciding a white part, around a potential part where development with toner is attained, so as to execute exposure with a light quantity for obtaining the potential between the potential at which the development with the toner is attained and an intermediate potential. SOLUTION: Two color toner images of first and second toner images formed on a photoreceptive drum 1 are corona-irradiated by a second electrifier 7, to make the polarities of the charges the same, that is, negative ones. A high voltage is applied from a power source 17 to the second electrifier 7. When the applied voltage is positive, first and second toners are set to obtain positive charges. When the applied voltage is negative, the first and second toners are set to obtain negative charges. An exposure control means 4 decides the white part around the potential by electrification. When it is decided that the white part is one around the potential part by the electrification, the exposure is executed with the light quantity by which the potential between the potential by the electrification and the intermediate potential is made. On the other hand, when it is decided that the white part is one around a discharge potential part, the exposure is executed with the light quantity by which the potential between a discharge potential and the intermediate potential is made. |
