JP2568244B

PURPOSE:To electrostatically transfer a toner image on an electrostatic image holding body onto transfer material under the negative ratio of a primary electrified field to a transfer electrified field by employing negatively electrified toner and one-component developer which includes resin particles possessing a prescribed particles diameter and triboelectrification characteristic. CONSTITUTION:A primary charger 2 negatively charges the surface of a photosensitive drum 1, and a latent image is formed with light from a light source or laser beam by exposure 5 and reversely developed with the negatively electrified toner and the one-component magnetic developer 13 including the resin particles possessing a mean particle diameter of 0.1-1.0mum and a triboelectrification characteristic of +50-+60muc/g by means of a developing device 9. When in this developing part, a bias is impressed between the drum 1 and a sleeve 4 to carry a transfer paper P to a transfer charger 3, it positively electrifies the back of the transfer paper P (opposite to the drum 1) to electrostatically transfer the negatively charged toner on the drum 1 onto the transfer paper P. After the charger 3 passes by, a destaticizing brush 10 destaticizes charges on the surface to separate the transfer paper P.