Patents by Inventor Kiyomasa Oga

Kiyomasa Oga 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).

  • Process for refining crude material for copper or copper alloy
    Patent number: 5364449
    Abstract: A process for refining a crude material for copper or copper alloy which contains as impurity elements at least one species of Pb, Ni, Sb, S, Bi, and As in combination with at least one species of Sn, Fe, and Zn, which comprises the sequential steps of (1) melting a crude material for copper or copper alloy, (2a) increasing the oxygen concentration in the melt, thereby oxidizing Sn, Fe, and Zn into slag, (this step is carried out if the crude material contains as impurity elements at least one species of Sn, Fe, and Zn) (2b) adding to the melt at least one species selected from the group consisting of Fe, Fe oxide, Mn, and Mn oxide, thereby causing Pb, Ni, Sb, S, Bi, and As in the melt to slag in the form of compound oxide of Fe and/or Mn, (3) removing the thus formed slag from the melt, and (4) subjecting the melt to reduction.
    Type: Grant
    Filed: March 15, 1993
    Date of Patent: November 15, 1994
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Takashi Nakamura, Kenji Osumi, Kiyomasa Oga, Motohiro Arai, Ryukichi Ikeda, Eiji Yoshida, Hirofumi Okada, Ryusuke Hamanaka