Patents by Inventor Hiroyuki Kokumai

Hiroyuki Kokumai 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).

  • Carbon-containing refractory
    Patent number: 4605635
    Abstract: The present invention provides a carbon-containing refractory composition characterized by containing 0.1-10 parts by weight of silicon hexaboride in 100 parts by weight of refractory material comprising 3-95 parts by weight of carbonaceous material such as graphite and 97-5 parts by weight of refractory aggregate.In the carbon-containing refractory composition of the present invention, silicon hexaboride is oxidized producing boron oxide on the surface of the refractory at a high temperature during operation, and the surface of the refractory is covered by the formation of a highly viscous molten liquid like kotoite (3 MgO.B.sub.2 O.sub.3), for example, which is formed from the components of the refractory, such as MgO, for example, thus particles of carbonaceous material such as graphite can be protected from oxidation.
    Type: Grant
    Filed: January 16, 1985
    Date of Patent: August 12, 1986
    Assignee: Shinagawa Refractories Co., Ltd.
    Inventors: Tadashi Zenbutsu, Hiroyuki Kokumai, Shinji Okikawa, Keiji Saito