Patents by Inventor Syuichiro Sanpei

Syuichiro Sanpei 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).

  • Industrial process for the production of diphenyl sulfone compounds
    Patent number: 7241924
    Abstract: A process for producing 4-isopropoxy-4?-hydroxydiphenyl sulfone useful as the developer for leuco dyes to be used in thermosensible papers, which is excellent in productivity, economical efficiency and safety and permits the production of the compounds from constantly available raw materials. This process is improved in productivity and economical efficiency as compared with those of the prior art both by shortening the production time by the use of an isopropyl iodide, which is more reactive than isopropyl bromide which have been used in the prior art.
    Type: Grant
    Filed: May 28, 2003
    Date of Patent: July 10, 2007
    Assignee: Nippon Soda Co., Ltd.
    Inventors: Syuichiro Sanpei, Masayuki Hanzawa, Yasuyuki Suzuki, Minoru Kaeriyama, Tomoya Hidaka, Toru Kawabe
  • Industrial process for the production of diphenyl sulfone compounds
    Publication number: 20040030191
    Abstract: A process for producing 4-isopropoxy-4′-hydroxydiphenyl sulfone useful as the developer for leuco dyes to be used in thermosensible papers, which is excellent in productivity, economical efficiency and safety and permits the production of the compounds from constantly available raw materials. This process is improved in productivity and economical efficiency as compared with those of the prior art both by shortening the production time by the use of an isopropyl iodide, which is more reactive than isopropyl bromide which have been used in the prior art.
    Type: Application
    Filed: May 28, 2003
    Publication date: February 12, 2004
    Inventors: Syuichiro Sanpei, Masayuki Hanzawa, Yasuyuki Suzuki, Minoru Kaeriyama, Tomoya Hidaka, Toru Kawabe
  • Industrial process for the production of diphenyl sulfone compounds
    Patent number: 6590126
    Abstract: A process for producing compounds of general formula (II) useful as the developer for leuco dyes to be used in thermosensible papers, which is excellent in productivity, economical efficiency and safety and permits the production of the compounds from constantly available raw materials. This process is improved in productivity, economical efficiency and safety as compared with those of the prior art both by shortening the production time by the use of, e.g., an alkyl iodide, RI, which is more reactive than alkyl bromides which have been used in the prior art, and by attaining the complete recovery and reuse of iodine by incorporating into the process the iodine recovery step of recovering iodine from the manufacturing wastewater and reacting this iodine with an alcohol to thereby self-produce an alkyl iodide.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: July 8, 2003
    Assignee: Nippon Soda Co., Ltd.
    Inventors: Syuichiro Sanpei, Masayuki Hanzawa, Yasuyuki Suzuki, Minoru Kaeriyama, Tomoya Hidaka, Toru Kawabe