| 摘要 |
PURPOSE:To obtain an always stable and sharp image by using a developer which consists of a magnetic toner having specific coercive force and specific volume resistivity and does not contain carrier particles and developing an electrostatic latent image with the magnetic toner which is frictionally and electrostatically charged. CONSTITUTION:The developer which consists of the magnetic toner and does not contain the carrier particles is supplied to a developing device having a developer supporting member and magnet. The magnetic toner is frictionally and electrostatically charged by relatively moving the magnet and the magnetic toner. The electrical latent image formed to the electrostatic image holding member disposed without contacting with the toner layer is developed by the frictionally and electrostatically charged magnetic toner, by which the toner image is transferred to a transfer material. The toner consists of a binder and magnetic powder. The magnetic powder which consists of an alloy or compd. of iron such as magnetite, hematite or ferrite or cobalt, nickel and manganese and has at least >=170 oersted coercive force is used. The specific volumetric resistivity of the magnetic toner is made >=10<12>OMEGANcm. |
