Patents by Inventor Yasushi Sengoku

Yasushi Sengoku 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: 4662984
    Abstract: A method of perforating through pores by etching in the manufacture of a shadow mask. This perforating method comprises the steps of selectively covering both surfaces of a thin metal plate with etching resistant film except a predetermined pore region; performing an etching to form recesses on the opening region of one surface of the metal plate; covering the one surface of the metal plate with an etching resistance material; etching the opening region of the other surface of the metal plate until the bottom of the etching resistance material buried in the recesses of the one surface of the metal plate is exposed; exposing both surfaces of the metal plate including the through holes by removing the etching resistant film and the etching resistant material; and etching the exposed surfaces of the metal plate again by contacting the exposed surface with an etchant.
    Type: Grant
    Filed: August 27, 1985
    Date of Patent: May 5, 1987
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhisa Ohtake, Makoto Kudou, Yasushi Sengoku