| 摘要 |
PURPOSE:To prevent charging up of an electrophotographic carrier by coating the surfaces of resin grains each having a volume average diameter of 30-100mum with one selected from magnetic metals and their oxides. CONSTITUTION:The resin particles having a volume average diameter of 30-100mum and adhesiveness to a magnetic metal are uniformly coated with the magnetic metal, such as Fe, Ni, or Co, or its oxide, such as magnetite, on the surfaces in an amount of 0.05-1.5wt% of the resin particles to form the carrier. As such a resin, styrene type, styrene-acrylic type, acrylic type resins and the like are enumerated, and above all, novolak type thermosetting phenolic resins are desirable. The preferable particle diameter of this granulated binder resin is 5-20mum, similar to the particle diameter of the general toner, thus permitting charging up to be prevented. |
