Patents by Inventor Fumio Shimizu

Fumio Shimizu 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 the preparation of O,O-dialkyl-S-benzyl thiophosphates
    Patent number: 4064200
    Abstract: O,O-Dialkyl-S-benzyl thiophosphates are obtained by reacting a diester of phosphorous acid such as dimethyl phosphite or diethyl phosphite, in an organic solvent such as toluene or xylene which is sparingly soluble or insoluble in water, with sulfur and an alkali or alkaline earth metal hydroxide or oxide such as NaOH or Ca(OH).sub.2, extracting the reaction product with water and then reacting the extract with a benzyl halide. In this manner, O,O-dialkyl-S-benzyl thiophosphates useful as agricultural and horticultural bactericidal and insecticidal agents are industrially advantageously obtained in a high purity and in a high yield.
    Type: Grant
    Filed: January 13, 1976
    Date of Patent: December 20, 1977
    Assignee: Ihara Chemical Kogyo Kabushiki Kaisha
    Inventors: Zenichi Sato, Fumio Shimizu, Shoji Kusano, Keiichiro Takagi, Yoji Imamiya