Patents by Inventor Joannes J. Van Beek

Joannes J. Van Beek 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).

  • Magnetic carrier particles
    Patent number: 4879198
    Abstract: A particulate material suited for serving as carrier particles for finely-divided toner particles in magnetic brush toner-carrier development of electrostatic charge patterns, said carrier particles comprising finely divided magnetite powder dispersed in a resin binder, characterized in that said magnetite powder is a mixture of magnetites wherein one type (A) of the magnetite has an oil absorption number in the range of 10 to 20 g/100 g pigment and another type (B) of the magnetite has an oil absorption number in the range of 20 to 40 g/100 g pigment. The binder contains hydrophilic functional groups and has an acid number in the range of 5 to 50 KOH/g.
    Type: Grant
    Filed: April 7, 1988
    Date of Patent: November 7, 1989
    Assignee: AGFA-Gevaert N.V.
    Inventors: Serge M. Tavernier, Joannes J. Van Beek, Pierre L. van Daele