| 摘要 |
PURPOSE:To obtain a fine reverse development picture by changing the electrostatical charging characteristics of a developing agent to be supplied to an area processing the uniform electrostatic charging processing of a latent image carrier and an unprocessed area. CONSTITUTION:A dielectric belt 1 uniformly electrostatically charged by a uniform electrostatic charger 2 is destaticized by the information inputted by a multistylus 3 and then reversely developed by toner having the charge of the same polarity as that of the charge of a part. If the charged polarity of the supplied developing agent is switched at the completion of passing of an unrecorded part of the dielectric belt 1 through a developing position alpha, the adhesion of the developing agent to the unrecorded part and the bad influence of the reversely charged developing agent can be prevented. A doctor bias power supply 8 is constituted of a two-way alteration type switch 8a and a pair of power supply 8b connected to respective contacts and can change the polarity of charge to be applied to the developing agent. |
