Patents by Inventor Shigeo Yokoyama

Shigeo Yokoyama 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).

  • Thiolcarbamate compounds and their use as herbicides
    Patent number: 4400199
    Abstract: Chloroalkylthiolcarbamate compounds of the formula: ##STR1## wherein Z represents ##STR2## and when Z is ##STR3## n is an integer of 4 to 10, whereas when Z is ##STR4## n is an integer of 3 to 10. These compounds are useful as effective herbicides having no harmful effect on the ecosystem, particularly extremely low toxicity to fish, and can be obtained, for example, by reacting the corresponding thiolcarbamate derivatives with a chloroalkyl halide.
    Type: Grant
    Filed: October 29, 1981
    Date of Patent: August 23, 1983
    Assignee: Asahi Kasei Kabashiki Kaisha
    Inventors: Shigeo Yokoyama, Teruyuki Misumi, Einosuke Fujimoto, Yutaka Kobayashi
  • Process for production of perfluorocarbon type cation exchange membrane
    Patent number: 4093568
    Abstract: A perfluorocarbon type cation exchange membrane prepared by treatment with an oxidizing agent of a cation exchange membrane containing perfluorocarbon polymers having specific pendant N-sulfonamide groups has improved electrochemical characteristics when used as a membrane in electrolysis of aqueous alkali halide solution.
    Type: Grant
    Filed: November 2, 1976
    Date of Patent: June 6, 1978
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Maomi Seko, Yasumichi Yamakoshi, Hirotsugu Miyauchi, Mitsunobu Fukumoto, Kyoji Kimoto, Itaru Watanabe, Shigeo Yokoyama