Patents Represented by Attorney R. A. Guloch
  • Patent number: 4287281
    Abstract: Magnetic toner compositions are prepared using two types of magnetic particles. The first type of magnetic particles have hydrophilic surface characteristics and the second type of magnetic particles have hydrophobic surface characteristics. Toner compositions are prepared by a dispersion polymerization technique wherein both types of magnetic pigment are dispersed in a vinyl monomer containing a polymerization initiator. This mixture of materials forms the discontinuous phase of a dispersion polymerization, the continuous phase being water containing a suspension stabilizing agent. The toner particles thus formed have the hydrophilic magnetic particles distributed on or near the surface of the toner particles while the hydrophobic magnetic particles are uniformly distributed throughout the remainder of the toner particles.
    Type: Grant
    Filed: October 22, 1979
    Date of Patent: September 1, 1981
    Assignee: Xerox Corporation
    Inventor: Robert D. Bayley