Patents by Inventor Eiichiro Koresawa

Eiichiro Koresawa 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).

  • Purification process of N-vinylformamide
    Patent number: 5959148
    Abstract: A purification process of N-vinylformamide, which comprises: providing a crude N-vinylformamide having an acetone-insoluble component content of not more than 400 ppm; and continuously feeding the crude N-vinylformamide into a fractionating tower, to obtain an N-vinylformamide having high purity. Also disclose is a continuous purification process of N-vinylformamide, which comprises the steps of: providing a crude N-vinylformamide; feeding the crude N-vinylformamide into a thin film evaporator to remove un-evaporated fraction from the system, and feeding the evaporated fraction containing N-vinylformamide into a fractionating tower, distilling the purified N-vinylformamide from the tower head, and discharging a bottom liquid containing N-vinylformamide from the tower bottom, and recycling the bottom liquid into the thin film evaporator to remove un-evaporated fraction from the system, and feeding the evaporated fraction into the fractionating tower.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: September 28, 1999
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Shin-ichi Sato, Takahiro Oshida, Hiroshi Izumikawa, Akihiko Tanaka, Eiichiro Koresawa