Patents by Inventor Robert O. Dark

Robert O. Dark 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: 4340273
    Abstract: The specification relates to retro-reflectors of the type used for road signs and markers and vehicle license plates to make these objects more noticeable to road users after dark. In the invention, the surface of a metal substrate is made retro-reflective by applying a layer of an organic polymeric material and adhering glass beads thereto, and then passing the substrate through a roller mill or the like with the glass beads covered by a platen so that the beads form indentations in the metal surface. The presence of the platen allows the pressing (indentation) step to take place without damage to the glass beads or to the layer between the beads and the metal surface. By this means, a hard metal article can be made directly retro-reflective.
    Type: Grant
    Filed: October 27, 1980
    Date of Patent: July 20, 1982
    Assignee: Alcan Research & Development Limited
    Inventors: Stanton E. Jack, Robert O. Dark
  • Patent number: 4265938
    Abstract: The specification relates to retro-reflectors of the type used for road signs and markers and vehicle license plates to make these objects more noticeable to road users after dark. In the invention, the surface of a metal substrate is made retro-reflective by applying a layer of an organic polymeric material and adhering glass beads thereto, and then passing the substrate through a roller mill or the like with the glass beads covered by a platen so that the beads form indentations in the metal surface. The presence of the platen allows the pressing (indentation) step to take place without damage to the glass beads or to the layer between the beads and the metal surface. By this means, a hard metal article can be made directly retro-reflective.
    Type: Grant
    Filed: September 13, 1979
    Date of Patent: May 5, 1981
    Assignee: Alcan Research & Development Limited
    Inventors: Stanton E. Jack, Robert O. Dark