Patents by Inventor Takao Maki

Takao Maki 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: 4423252
    Abstract: Bisphenols are prepared by condensation of a phenol with a ketone in the presence of a sulfonic acid type cation exchange resin partially modified with a pyridinealkanethiol of the formula:Py--(CH.sub.2).sub.n SHwherein n is a positive integer and Py is 3-pyridyl when n is 1, or 2-, 3- or 4-pyridyl when n is more than 1.
    Type: Grant
    Filed: July 2, 1981
    Date of Patent: December 27, 1983
    Assignee: Mitsubishi Chemical Industries Limited
    Inventors: Takao Maki, Tetsuo Masuyama, Toshiharu Yokoyama, Yoshiko Fujiyama
  • Patent number: 4405823
    Abstract: A process for producing phenols from benzenemonocarboxylic acids, or their salts, esters, or anhydrides is described, comprising contacting these starting materials with molecular oxygen-containing gas and steam in a liquid phase in the presence of a copper compound, a manganese compound, and a rare earth element compound. This process can be performed either by a one-step reaction method or by a two-step reaction method. In accordance with the present process, the formation of by-products such as high boiling by-products or diphenyl ethers is inhibited and the selectivity of phenols can be greatly increased.
    Type: Grant
    Filed: August 24, 1982
    Date of Patent: September 20, 1983
    Assignee: Mitsubishi Chemical Industries Limited
    Inventors: Takao Maki, Tetsuo Masuyama, Toshiharu Yokoyama
  • Patent number: 4319054
    Abstract: There is disclosed a process for producing pyrogallol by dehydrogenation of cyclohexane-1,2,3-triol in the presence of a platinum group metal catalyst in an inert gas stream. The catalyst contains, as modifier, (a) at least one alkali metal salt and/or (b) at least one member selected from the group consisting of gold, tellurium, silver, arsenic, selenium, indium, antimony, bismuth, copper and zinc, with the Pd-Te catalyst being preferred. The catalyst ingredients are supported on a carrier. The process gives high selectivity of pyrogallol.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: March 9, 1982
    Assignee: Mitsubishi Chemical Industries Limited
    Inventors: Takao Maki, Kenji Murayama
  • Patent number: 4013691
    Abstract: A cyclohexanone is oxidized by molecular oxygen in the presence of an aldehyde, a soluble compound of a metal selected from the group consisting of iron, palladium, vanadium, chromium, molybdenum, tungsten and cerium, and a compound which has a heterocyclic ring containing at least one nitrogen atom and which acts as a multidantate ligand, to form an epsilon-caprolactone and a carboxylic acid corresponding to the aldehyde.
    Type: Grant
    Filed: October 8, 1975
    Date of Patent: March 22, 1977
    Assignee: Mitsubishi Chemical Industries Ltd.
    Inventors: Takao Maki, Kazuyuki Mineta