| 摘要 |
PURPOSE:To obtain a magnetic toner of red, yellow, purple, and sepia colors capable of obtaining a sharp color image by binding with a resin, a magnetic material made of gamma-Fe2O3 having metal oxide coprecipitated on the surface. CONSTITUTION:A magnetic color toner consists of a magnetic material composed essentially of gamma-Fe2O3 with a metal oxide coprecipitated on the surface, and a binder resin. Various kinds of additive ordinarily used may added properly when needed. Said employed metal oxide is enumerated by oxides of Zn, Ni, Co, Mg, Cu, or Cd. The total amt. of said metal oxide is, preferably 0.1-60mol% of the molar quantity of magnetic material converted from ferrite or magnetite into terms of Fe2O3. When said oxide is <0.1mol%, effects of actions due to van der vaals force between the metal oxide and magnetic moment is not sufficient, and when >60mol%, image density during development tends to lower, and both cases are undesirable. |
