Patents by Inventor Bret Martin Johnston

Bret Martin Johnston 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).

  • Process for preparing colored toner particles
    Patent number: 7169528
    Abstract: A process for the preparation of colored polymeric toner particles includes: forming an organic phase by dissolving an organic polymer and, optionally, one or more additives in a water-immiscible organic solvent; forming a dispersion by combining the organic phase with an aqueous phase comprising a particulate stabilizer, a colorant, and, optionally, a promoter, with the proviso that when the colorant is carbon black, it is an acidic carbon black having a pH less than 7; homogenizing the dispersion to form droplets containing the organic solvent, organic polymer, and colorant; removing the organic solvent from the droplets to form colored polymeric toner particles; and separating and drying the toner particles.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: January 30, 2007
    Assignee: Eastman Kodak Company
    Inventors: Hichang Yoon, Bret Martin Johnston, Dinesh Tyagi, Michael Thomas Regan