Patents by Inventor John R. Hagerstrom

John R. Hagerstrom 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).

  • Inks for pulsed electrical printing
    Patent number: 4296176
    Abstract: A printing ink comprises particles of small size, each having a body portion consisting of a fusible resin and a colorant and electrically conductive material situated substantially entirely on the surface of the body portion. The particles may be formed by a variety of methods. The body portion may have a magnetizable constituent for use in printers with magnetic ink orientation. The particles may be formed by spray drying to produce hollow beads.
    Type: Grant
    Filed: December 11, 1979
    Date of Patent: October 20, 1981
    Assignee: EPP Corp.
    Inventors: Donald J. J. Lennon, John R. Hagerstrom, C. Frederick W. Ekman
  • Inks for pulsed electrical printing and methods of producing same
    Patent number: 4273847
    Abstract: A printing ink comprises particles of small size, each having a body portion consisting of a fusible resin and a colorant and electrically conductive material situated substantially entirely on the surface of the body portion. The particles may be formed by a variety of methods. The body portion may have a magnetizable constituent for use in printers with magnetic ink orientation. The particles may be formed by spray drying to produce hollow beads.
    Type: Grant
    Filed: December 12, 1979
    Date of Patent: June 16, 1981
    Assignee: EPP Corp.
    Inventors: Donald J. J. Lennon, John R. Hagerstrom, C. Frederick W. Ekman