| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a conductive toner with improved developing performance and transfer performance and to provide a developing device using the conductive toner and an image forming apparatus. <P>SOLUTION: The conductive toner 3 is to be used for a developing device equipped with a toner carrier 4 which is disposed opposing to an image carrier 2 carrying an electrostatic latent image 1 and which carries a charged conductive toner 3, and with a development electric field forming means 5 which generates a development electric field between the toner carrier 4 and the image carrier 2 to develop the electrostatic latent image 1 on the image carrier 2 with the toner in the development electric field region. The toner has a variable resistance part 7 on the surface of an insulating toner base 6, which varies into high resistance in a development electric field and into low resistance in a charge injection electric field which is higher than the development electric field. The variable resistance part 7 has a coating layer comprised of the layered structure of at least two layers or more including an insulating outermost layer 8 having insulating property and a conductive inner layer 9 having conductivity. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
