Electrophotographic process with magnetic brush development using semiconductive ferrite carriers
AssigneesHitachi Metals, Ltd., Hitachi, Ltd.
InventorsTsuneaki Kawanishi, Yasuki Mori, Koji Noguchi, Tsutomu Iimura
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Abstract
In a method of developing triboelectric magnetic toner, an electrostatic latent image is formed on a substance, the latent image is developed by a magnetic brush method using a ferrite carrier of semiconductivity and a triboelectric magnetic tonor, and the developed toner image is transferred to a transfer member and fixed. By adding the semiconductive ferrite carrier, a lump of tonor is broken with a mechanical force of the carrier so as to increase the flowability of the tonor and to prevent the agglomeration of the tonor due to dielectric charging.
Claims14
A method of electrophotography characterized:
- in that an electrostatic latent image is formed on the surface of a substance layer;
- in that said electrostatic latent image is developed by a magnetic brush method using semiconductive ferrite carriers and triboeletric magnetic toner with a chargeability to provide the magnetic brush, the ferrite carriers having a saturated magnetization of 20 to 90 emu/g and the magnetic toner having an intrinsic volume resistance exceeding 10.sup.14 .OMEGA..multidot.cm when an electric field of a direct current of 4,000 V/cm is applied, with the magnetic brush moving at high speeds and in the same direction relative to the substance layer;
- and in that the developed toner image is transferred to a transfer member and then fixed.
Dependencies are inferred from the claim text.