| 摘要 |
PURPOSE:To perform excellent color picture transferring by using a toner having a value of specific charge of the toner is almost made uniform with the precharge before transferring, independently of the types of the toner supplies for the formation of reproduced image. CONSTITUTION:For example, a toner having greater dielectric constant than that of a positive toner is used for a negative toner. When a toner with 11.4 of dielectric constant is used, the specific charge of the toner is 27muO/g by performing the positive pre-charge, allowing to arrange the specific charge almost with that of the positive toner. Thus, the specific charge of both the toners can be made uniform by increasing the dielectric constant of the toner the polarity of which is inverted at the pre-charge process than that of the other toner, allowing to uniform the transfer of the toner image. Further, since the transfer becomes difficult if the toner specific charge >=40muO/g, the specific charge is used at <=40muO/g even under the pre-charge. |
