Patents by Inventor Takahiko Nakai

Takahiko Nakai 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: 4741745
    Abstract: Diisopropyl ethers of oligomers of ethylene glycol having between 2 and 8 ethylene glycol moieties and an average molecular weight between 190 and 300, are more useful physical absorption solvents for the separation of acid gases than are dimethyl, diethyl, ethyl butyl, propyl butyl, dibutyl, or higher alkyl ethers of the same ethylene glycol oligomers, because of a combination of high solution capacity, high separation efficiencies, low viscosity, low gas pressure, and resistance to hydrolysis during use. The diisopropyl ether of diethylene glycol is especially advantageous for use at absorber temperatures below 0.degree. C. Because of low viscosity, the diisopropyl ethers can often be substituted in separation equipment designed for use with chemical rather than physical solvents, thereby realizing the lower operating costs associated with physical solvents without requiring new capital investment.
    Type: Grant
    Filed: April 27, 1987
    Date of Patent: May 3, 1988
    Assignee: Norton Company
    Inventors: Yukio Kadono, Minoru Miyagawa, Takahiko Nakai, Minoru Saotome
  • Patent number: 4389338
    Abstract: In a method for the manufacture of a silver catalyst having silver deposited on a porous inorganic carrier in conjunction with at least one reaction accelerator selected from the group consisting of alkali metals and thallium to be used for the production of ethylene oxide, the improvement comprising the steps of depositing silver on the porous inorganic carrier in conjunction with at least one reaction accelerator selected from the group consisting of alkali metals and thallium thereby preparing an activated silver catalyst and subsequently subjecting said silver catalyst to a high-temperature treatment at a temperature in the range of 550.degree. to 950.degree. C. in an inert gaseous atmosphere having an oxygen concentration of not more than 3 volume percent in the final step.
    Type: Grant
    Filed: December 17, 1981
    Date of Patent: June 21, 1983
    Assignee: Nippon Skokubai Kagaku Kogyo Co., Ltd.
    Inventors: Masashi Mitsuhata, Shin-ichi Nagase, Takahiko Nakai, Toshihiko Kumazawa