Patents by Inventor Jahn P. Hoekstra

Jahn P. Hoekstra 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).

  • Patent number: 5176947
    Abstract: Improved electroerosion recording media can be prepared by utilizing, on top of a polyester, paper, or metal substrate, a polyvinylbutyral polymer cross-linked with a mixed phenol-tert-butylphenol formaldehyde cross-linking agent as a base layer, and an erodible metallic layer sufficiently thin to be erodible in response to current pulses delivered by a stylus of an electroerosion printer. In a preferred embodiment, the polymeric layer further contains silica. The recording medium may also be top coated with a lubricating agent. The formulation provides excellent adhesion of the conductive layer, and allows the thickness of the aluminum to be increased up to 75%, resulting in an optical density (with aluminum as the metallic layer) of up to 3.5.
    Type: Grant
    Filed: December 7, 1990
    Date of Patent: January 5, 1993
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Mukesh K. Desai, Jahn P. Hoekstra, Keith S. Pennington, Eva E. Simonyi