Patents by Inventor Seiko Igarashi

Seiko Igarashi 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 producing mesophase pitch
    Patent number: 4533461
    Abstract: A substantially uniform mesophase pitch is prepared by treating a mesophase forming pitch material at elevated temperatures above about 380.degree. C. to produce a mixture of mesophase and non-mesophase pitch containing about 20% to about 80% mesophase. The mixture is then maintained at a temperature below about 400.degree. C. for a time sufficient to allow the mesophase to coalesce and settle as a lower separable layer. A mesophase pitch so produced may contain from 90 to 100% mesophase with a softening point of less than 320.degree. C.
    Type: Grant
    Filed: July 8, 1981
    Date of Patent: August 6, 1985
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Takayuki Izumi, Tsutomu Naito, Seiko Igarashi
  • Process for producing mesophase pitch
    Patent number: RE32792
    Abstract: A substantially uniform mesophase pitch is prepared by treating a mesophase forming pitch material at elevated temperatures above about 380.degree. C. to produce a mixture of mesophase and non-mesophase pitch containing about 20% to about 80% mesophase. The mixture is then maintained at a temperature below about 400.degree. C. for a time sufficient to allow the mesophase to coalesce and settle as a lower separable layer. A mesophase pitch so produced may contain from 90 to 100% mesophase with a softening point of less than 320.degree. C.
    Type: Grant
    Filed: November 3, 1986
    Date of Patent: November 29, 1988
    Assignee: Toa Nenryo Kogyo Kabushiki Kaisha
    Inventors: Takayuki Izumi, Tsutomu Naito, Seiko Igarashi