Patents by Inventor Margate T. Thomas

Margate T. Thomas has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Charge control agent combination for a liquid toner
    Patent number: 5200289
    Abstract: A liquid toner composition for electrophotography comprising a dispersion which includes a carrier liquid, pigmented or dyed toner particles, an inorganic binder insoluble in the carrier liquid at room temperature and a charge control agent in a charge directing amount, said charge control agent comprising lecithin, 1% to 2.5% by weight, based on the total weight of active components in the charge control agent, of an alkylated N-vinyl pyrrolidone polymer, and 0.5% to 10% by weight, based on the total weight of active components in the charge control agent, of an oil soluble or dispersible anionic surfactant.
    Type: Grant
    Filed: December 4, 1991
    Date of Patent: April 6, 1993
    Assignee: AM International Incorporated
    Inventors: Roy J. Harrington, George A. Gibson, Margate T. Thomas