Patents by Inventor Gerriet H. Douma

Gerriet H. Douma 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).

  • Method for making visible defects in surfaces
    Patent number: 3995483
    Abstract: A method and a device for making visible defects in surfaces, in particular hot surfaces, by applying to the surface a penetrating liquid comprising a dye that soaks in the defects, removing the excess of liquid, applying on to the surface a developer such as a synthetic resin, which, after the dye from the defects has migrated into the former, is cured by the heat content of the surfaces into a replica of the surface in which the reversed image of the defects has been recorded and a replica made according to the method.
    Type: Grant
    Filed: August 19, 1975
    Date of Patent: December 7, 1976
    Assignee: United Technologies Corporation
    Inventors: Antoon Th. A. Hartong, Gerriet H. Douma