Patents by Inventor John F. Birtles

John F. Birtles 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).

  • Off-set printing by silk screening an intermediate surface and transferring the image to an article by an off-set pad
    Patent number: 5054390
    Abstract: An ink design is silk screened onto an intermediate surface and is then transferred to an article by a deformable pad. In order to provide a large difference in the ink affinities of the intermediate surface and pad, these are made of silicone rubbers in which different catalysts are used in the curing of the rubbers. Dibutyltindilaurate as catalyst provides an intermediate surface of low ink affinity which can enable 100% transfer of ink from the intermediate surface to the pad when a stannous octoate catalyzed, condensation cured rubber, or a suitable addition cured rubber, is used for the pad. The screen is heated to a greater temperature than that of the intermediate surface.
    Type: Grant
    Filed: January 28, 1988
    Date of Patent: October 8, 1991
    Assignee: British Ceramic Research Association Ltd.
    Inventors: John F. Birtles, Robert D. Brett, Wilfred Roberts