| 摘要 |
<p>The present invention provides for a method for the preparation of red colored magnetic particles for multicomponent toner compositions which are highly conductive and therefore suitable for use as developers in high speed electrophotographic copy machines embodying magnetic brush development. Suitable magnetic core metal particles are provided which are subsequently coated with finely divided particles of copper oxide (CuO). The copper oxide coating is then reduced in-situ on the surface of the core particle to provide an electrically conductive core particle uniformly coated with adherent metallic copper, which particle is of a red color. The present invention also provides a method for controlling and adjusting the electrical conductivity and color of toner materials as a function of the amount of metallic copper deposited on the surface of the magnetic core materials.</p> |
