Patents by Inventor Etsuo Takemoto

Etsuo Takemoto 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).

  • Highly purified 1-aminopropanediol-2,3
    Patent number: 5886228
    Abstract: 1-aminopropanediol-2,3 containing 2-aminopropanediol-1,3 of less than 0.30% by weight can be prepared by the present purification process, which comprises distilling a 1-aminopropanediol-2,3 containing at least 0.3% of 2-aminopropanediol-1,3 based on the weight of 1-aminopropanediol-2,3 with a distillation column, said distillation column having low pressure loss.
    Type: Grant
    Filed: November 28, 1997
    Date of Patent: March 23, 1999
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Hiroshi Koyama, Etsuo Takemoto
  • Process for the preparation of a dihydroxyamino compound
    Patent number: 5874624
    Abstract: Disclosed are a process for the preparation of a dihydroxyamino compound in which water and discoloring ingredients are removed while preventing decomposition of a dihydroxyamino compound by distilling a crude reaction liquid containing an epoxy compound and an amino compound at a specified temperature and pressure, a process for improving a yield of a dihydroxyamino compound having high purity by recirculating an aqueous solution of an amino compound recollected from a crude reaction liquid into a reaction step, and a process in which there are prevented discoloration and a yield decline of a dihydroxyamino compound.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: February 23, 1999
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Akira Horiguchi, Akihisa Takabe, Etsuo Takemoto
  • Highly purified 1-aminopropanediol-2,3
    Patent number: 5750792
    Abstract: 1-aminopropanediol-2,3 containing 2-aminopropanediol-1,3 of less than 0.30% by weight can be prepared by the present purification process, which comprises distilling a l-aminopropanediol-2,3 containing at least 0.3% of 2-aminopropanediol-1,3 based on the weight of 1-aminopropanediol-2,3 with a distillation column, said distillation column having low pressure loss.
    Type: Grant
    Filed: December 6, 1996
    Date of Patent: May 12, 1998
    Assignee: Daicel Chemical Industrial, Ltd.
    Inventors: Hiroshi Koyama, Etsuo Takemoto
  • Method for the purification of 1-aminopropanediol-2,3
    Patent number: 5556516
    Abstract: 1-aminopropanediol-2,3 containing 2-aminopropanediol-1,3 of less than 0.30% by weight can be prepared by the present purification process, which involves distilling a 1-aminopropanediol-2,3 containing at least 0.3% of 2-aminopropanediol-1,3 based on the weight of 1-aminopropanediol-2,3 using a distillation column, said distillation column having low pressure loss.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: September 17, 1996
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Hiroshi Koyama, Etsuo Takemoto
  • Recovery of tungsten compounds
    Patent number: 4629606
    Abstract: The present invention provides a process for recovering a tungsten compound from a waste liquor containing a high-boiling organic compound and the tungsten compound, which process comprises the steps of spray-burning said waste liquor at an air ratio of 1.05 or higher under conditions of a temperature and a residence time which lie within the region of a pentagon defined by points A, B, C, D, and E in FIG. 1; quenching the combustion product by immediately bringing it into direct contact with water; and recovering the tungsten compound.
    Type: Grant
    Filed: July 16, 1985
    Date of Patent: December 16, 1986
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Yoshiyuki Imagire, Teruhiko Hirabayashi, Nobuo Nonaka, Toshifumi Kitagawa, Yasukazu Murakami, Iwao Abe, Shinzo Uda, Osamu Ohshima, Etsuo Takemoto