Patents by Inventor Koichi Kashiwagi

Koichi Kashiwagi 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).

  • Patent number: 5731453
    Abstract: A diaryl carbonate with a high degree of purity is produced at a high yield by (A) subjecting (a) a diaryl oxalate and a phenol compound or (b) an alkylaryl oxalate to transesterification reaction in one or two stages in the presence of a catalyst to prepare a diaryl oxalate, while removing a by-product from the reaction system; (B) collecting the diaryl oxalate from the resultant reaction product mixture of the step (A); (C) subjecting the diaryl oxalate to a decarbonylation reaction, preferably in the presence of a phosphorous compound-containing catalyst, to convert the diaryl oxalate to a corresponding diaryl carbonate, while removing a reaction by-product comprising carbon monoxide from the reaction system; and (D) collecting the diaryl carbonate from the reaction product mixture of the step (C).
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: March 24, 1998
    Assignee: Ube Industries, Ltd.
    Inventors: Keigo Nishihira, Shuji Tanaka, Yuki Nishida, Hirofumi Ii, Satoru Fujitsu, Katsumasa Harada, Ryoji Sugise, Koichi Kashiwagi, Takashi Doi
  • Patent number: 5648510
    Abstract: A diaryl carbonate is prepared at a high yield and a high selectivity by heating a diaryl oxalate in the presence of an organic phosphorous compound to release carbon monoxide therefrom. A halogen atom-containing compound can be employed in combination with the organic phosphorous compound.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: July 15, 1997
    Assignee: Ube Industries, Ltd.
    Inventors: Katsumasa Harada, Yoichi Imbe, Keigo Nishihira, Shuji Tanaka, Satoru Fujitsu, Ryoji Sugise, Koichi Kashiwagi, Toshihiko Sumida