Patents by Inventor Tadayoshi Ugamura

Tadayoshi Ugamura 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: 10443013
    Abstract: A viscosity index improver comprising a polymer which has a high viscosity index and good shear stability and which exhibits sufficient solubility in a lubricating base oil, a process for producing the same, and a lubricating oil composition containing the viscosity index improver are provided, wherein the viscosity index improver comprising a polymer satisfying the following (1) to (4): (1) weight-average molecular weight (Mw) of 200,000 or more and 600,000 or less; (2) number-average molecular weight (Mn) of 90,000 or more; (3) molecular weight distribution (Mw/Mn) of 4.0 or less; and (4) branching degree of 1.0 or more.
    Type: Grant
    Filed: September 15, 2015
    Date of Patent: October 15, 2019
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Tadayoshi Ugamura, Kazunari Yasumura, Keiko Izumi
  • Publication number: 20170233675
    Abstract: A viscosity index improver comprising a polymer which has a high viscosity index and good shear stability and which exhibits sufficient solubility in a lubricating base oil, a process for producing the same, and a lubricating oil composition containing the viscosity index improver are provided, wherein the viscosity index improver comprising a polymer satisfying the following (1) to (4): (1) weight-average molecular weight (Mw) of 200,000 or more and 600,000 or less; (2) number-average molecular weight (Mn) of 90,000 or more; (3) molecular weight distribution (Mw/Mn) of 4.0 or less; and (4) branching degree of 1.0 or more.
    Type: Application
    Filed: September 15, 2015
    Publication date: August 17, 2017
    Applicant: NIPPON SHOKUBAI CO., LTD.
    Inventors: Tadayoshi UGAMURA, Kazunari YASUMURA, Keiko IZUMI
  • Publication number: 20040019152
    Abstract: It is an object of the present invention, which has been made in view of the above-mentioned state of the art, to provide a protolytically leaving group-containing copolymer which can exhibit high levels of changes in characteristics, such as solubility in alkaline aqueous solutions after free proton treatment as compared with the, solubility before such treatment, and of substrate adhesion, developability, chemical resistance and etching resistance and which can judiciously be applied in various fields of application.
    Type: Application
    Filed: April 24, 2003
    Publication date: January 29, 2004
    Applicant: Nippon Shokubai Co., Ltd.
    Inventors: Yohei Murakami, Masatoshi Yoshida, Osamu Konosu, Shinichi Goto, Motohiro Arakawa, Tadayoshi Ugamura