| 摘要 |
PURPOSE:To obtain copies having good image quality, by developing an electrostatic latent image with a toner having dielectric constant at a specified value or lower in repeating development and transfer using only one electrostatic latent image once formed on a charge retaining material to obtain plural sheets of copies. CONSTITUTION:When an electrostatic latent image is developed, a developed toner image is formed on the electrostatic latent image. At that time, charge is generated in the toner layer in accordance with the electrostatic capacity by electrostatic induction from the electrostatic latent image. A part or the total amt. of this charge is simultaneously consumed when the developed toner is consumed from the development step to the transfer step, and as a result, charge of the electrostatic latent image is attenuated. In the case of making plural copies, such consumption of charge of the latent image is repeated with respect to the same one image, and therefore, it is presumed that this is one of the factors deteriorating the electrostatic latent image. Such transfer of charge from the latent image to the toner layer becomes smaller, as the electrostatic capacity of the toner layer becomes smaller, that is, the dielectric constant of the toner becomes smaller, and to satisfy the requirements of practicable image quality, the dielectric constant must be reduced to <=3.5. |
