Patents by Inventor Noriyuki Hirowatari

Noriyuki Hirowatari 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).

  • Method of purifying aromatic dicarboxylic acids
    Patent number: 5565609
    Abstract: There is provided a method of purifying a crude aromatic dicarboxylic acid which comprises purifying an aqueous solution of an organic amine salt of the crude aromatic dicarboxylic acid, and then thermally decomposing the organic amine salt whereby to recover the thus highly purified aromatic dicarboxylic acid.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: October 15, 1996
    Assignee: Mitsui Petrochemical Industries, Ltd.
    Inventors: Noriyuki Hirowatari, Hiroyasu Ohno, Kenji Shimamoto
  • Process for preparing resorcinol
    Patent number: 4283570
    Abstract: A process for preparing resorcinol in improved yields while avoiding the formation of reactive by-products which comprises(1) a first step of pre-treating an oxidation product of m-diisopropylbenzene composed of m-diisopropylbenzene dihydroperoxide and by-product m-substituted carbinol hydroperoxide and/or dicarbinol with hydrogen peroxide in the presence of an acid catalyst in a heterogeneous system of an aqueous aromatic hydrocarbon solvent under conditions which do not substantially cause the acid cleavage, the pretreatment being performed while removing by-product water as an azeotrope with the aromatic hydrocarbon in the treating system, and(2) a second step of acid-cleaving the pre-treated reaction product in the substantial absence of hydrogen peroxide.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: August 11, 1981
    Assignee: Mitsui Petrochemical Industries Ltd.
    Inventors: Hiroaki Nakagawa, Noriyuki Hirowatari, Takayuki Nakamura