Patents by Inventor Junya Katoh

Junya Katoh 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 preparing polyarylene thioether
    Patent number: 5250657
    Abstract: Polyarylene thioether is easily prepared by oxidative polymerizing an aromatic compound of the formula: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently a hydrogen atom, a halogen atom, a lower alkyl group or a lower alkoxy group, and Y is a hydrogen atom or a group of the formula: ##STR2## wherein R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are independently a hydrogen atom, a halogen atom, a lower alkyl group or a lower alkoxy group and X is --O--, --S--, a methylene group or an ethylene group with a sulfidizing agent in the presence of an acid and an oxidizing agent, or in the presence of an acid, a catalyst for oxidative polymerization and oxygen, or in the presence of a Friedel-Crafts catalyst.
    Type: Grant
    Filed: January 29, 1991
    Date of Patent: October 5, 1993
    Assignee: Seisan Kaihatsu Kagaku Kenkyusho
    Inventors: Eishun Tsuchida, Hiroyuki Nishide, Kimihisa Yamamoto, Mitsutoshi Jikei, Junya Katoh