Patents by Inventor Akira SUGAWA

Akira SUGAWA 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: 10822525
    Abstract: Embodiments provide a polishing composition containing colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound. According to at leaset one embodiment, the water-soluble polymer compound is a copolymer containing a structural unit derived from an unsaturated aliphatic carboxylic acid and a structural unit derived from an unsaturated amide.
    Type: Grant
    Filed: March 26, 2018
    Date of Patent: November 3, 2020
    Assignee: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru Iwata, Akira Sugawa
  • Patent number: 10662272
    Abstract: Embodiments provide a polishing composition for a magnetic disk substrate containing colloidal silica, a water-soluble polymer, and water. The water-soluble polymer compound is a copolymer containing a monomer having a carboxylic acid group, a monomer having an amide group, and a monomer having a sulfonic acid group as essential monomers. The water-soluble polymer compound has a weight average molecular weight of 1,000 to 1,000,000.
    Type: Grant
    Filed: October 24, 2018
    Date of Patent: May 26, 2020
    Assignee: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventor: Akira Sugawa
  • Publication number: 20190119422
    Abstract: Embodiments provide a polishing composition for a magnetic disk substrate containing colloidal silica, a water-soluble polymer, and water. The water-soluble polymer compound is a copolymer containing a monomer having a carboxylic acid group, a monomer having an amide group, and a monomer having a sulfonic acid group as essential monomers. The water-soluble polymer compound has a weight average molecular weight of 1,000 to 1,000,000.
    Type: Application
    Filed: October 24, 2018
    Publication date: April 25, 2019
    Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventor: Akira SUGAWA
  • Publication number: 20180215953
    Abstract: Embodiments provide a polishing composition containing colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound. According to at leaset one embodiment, the water-soluble polymer compound is a copolymer containing a structural unit derived from an unsaturated aliphatic carboxylic acid and a structural unit derived from an unsaturated amide.
    Type: Application
    Filed: March 26, 2018
    Publication date: August 2, 2018
    Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru IWATA, Akira SUGAWA
  • Patent number: 9862863
    Abstract: Embodiments of the invention provide a polishing composition including colloidal silica having an average particle size of 5 to 200 nm and pulverized wet-process silica particles having an average particle size of 0.1 to 1.0 ?m, wherein a value of the ratio of the average particle size of the wet-process silica particles to that of the colloidal silica is from 2.0 to 30.0. The polishing composition, according to various embodiments, achieves a high polishing rate and has a good surface smoothness, without the use of alumina particles.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: January 9, 2018
    Assignee: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru Iwata, Akira Sugawa
  • Patent number: 9856401
    Abstract: Embodiments of the invention provide a polishing composition including colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound, wherein the water-soluble polymer compound is a polymer or copolymer having a constituent unit derived from an unsaturated aliphatic carboxylic acid. Various embodiments achieve a high polishing rate and obtain a good surface smoothness and end-face shape without the use of alumina particles.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: January 2, 2018
    Assignee: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru Iwata, Akira Sugawa
  • Publication number: 20170015868
    Abstract: Embodiments of the invention provide a polishing composition including colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound, wherein the water-soluble polymer compound is a polymer or copolymer having a constituent unit derived from an unsaturated aliphatic carboxylic acid. Various embodiments achieve a high polishing rate and obtain a good surface smoothness and end-face shape without the use of alumina particles.
    Type: Application
    Filed: September 28, 2016
    Publication date: January 19, 2017
    Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru IWATA, Akira SUGAWA
  • Publication number: 20170015867
    Abstract: Embodiments of the invention provide a polishing composition including colloidal silica having an average particle size of 5 to 200 nm and pulverized wet-process silica particles having an average particle size of 0.1 to 1.0 ?m, wherein a value of the ratio of the average particle size of the wet-process silica particles to that of the colloidal silica is from 2.0 to 30.0. The polishing composition, according to various embodiments, achieves a high polishing rate and has a good surface smoothness, without the use of alumina particles.
    Type: Application
    Filed: September 28, 2016
    Publication date: January 19, 2017
    Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.
    Inventors: Toru IWATA, Akira SUGAWA