Patents by Inventor Chusei Seki

Chusei Seki 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).

  • Gold alloy for black coloring, processed article of black colored gold alloy and method for production of the processed article
    Patent number: 5139739
    Abstract: A gold alloy for black coloring comprising gold and at least one coloring metallic element selected from the group consisting of Cu, Fe, Co, and Ti, a gold alloy for black coloring having the composition described above and further comprising at least one alloying element selected from the group consisting of Pt, Pd, Rh, Ir, Ru, Os, Ag, and Ni; a method for the production of a processed article of gold alloy possessing a black surface layer by the steps of shaping the gold alloy mentioned above, heat-treating the shaped gold alloy, and cooling; and processed article of gold alloy obtained by the method.
    Type: Grant
    Filed: April 9, 1991
    Date of Patent: August 18, 1992
    Assignees: Agency of Industrial Science and Technology, Ministry of International Trade and Industry, Seki Company
    Inventors: Takeshi Takayanagi, Noboru Morita, Chusei Seki