Patents by Inventor Tomoko MURAHASHI

Tomoko MURAHASHI 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).

  • Permeability evaluation method
    Patent number: 10598622
    Abstract: A permeability evaluation method for evaluating permeability of heavy metal ions through a specimen, comprising a step of, in a state in which a first liquid containing heavy metal ions and a second liquid containing water and an organic solvent are separated by a specimen, applying a voltage between a positive electrode provided on the side of the first liquid and a negative electrode provided on the side of the second liquid and measuring the value of the current flowing between the positive electrode and the negative electrode, wherein the specimen contains an insulating material used in semiconductor production, and the heavy metal ion concentration of the first liquid is 0.5 mg/kg or more.
    Type: Grant
    Filed: April 15, 2014
    Date of Patent: March 24, 2020
    Assignee: HITACHI CHEMICAL COMPANY, LTD.
    Inventors: Koji Suzumura, Kazuhiro Yamamoto, Tomoko Murahashi
  • PERMEABILITY EVALUATION METHOD
    Publication number: 20170038324
    Abstract: A permeability evaluation method for evaluating permeability of heavy metal ions through a specimen, comprising a step of, in a state in which a first liquid containing heavy metal ions and a second liquid containing water and an organic solvent are separated by a specimen, applying a voltage between a positive electrode provided on the side of the first liquid and a negative electrode provided on the side of the second liquid and measuring the value of the current flowing between the positive electrode and the negative electrode, wherein the specimen contains an insulating material used in semiconductor production, and the heavy metal ion concentration of the first liquid is 0.5 mg/kg or more.
    Type: Application
    Filed: April 15, 2014
    Publication date: February 9, 2017
    Applicant: Hitachi Chemical Co., Ltd.
    Inventors: Koji SUZUMURA, Kazuhiro YAMAMOTO, Tomoko MURAHASHI