| 摘要 |
PURPOSE:To prevent fogging and obtain a sharp image by limiting the gap between a base electrode and a counter electrode within a specific range in a flying process of photoconductive toner from the base electrode to the counter electrode, and applying an AC voltage containing a DC component between both electrodes. CONSTITUTION:The counter electrode 7 is provided opposite the base electrode 2 at an interval of 50mum-1mm., preferably, 100-750mum and the bias voltage consisting of the AC voltage V2 containing a DC voltage V1 is impressed between both electrodes to charge electrostatically the counter electrode 7 negatively. Those DC voltage V1 and AC voltage V2 are impressed in the flying process, so toner particles which are charged electrostatically positively with an electrostatic charge distribution on the base electrode 2 are oscillated with the AC voltage and coagulation is suppressed, thereby collapsing clustes. Consequently, all toner particles which are charged electrostatically positively are easy to fly to the counter electrode 7, so a fogfree sharp image corresponding to a positive original image if obtained in a following transfer process. |
