Patents by Inventor Toyoshiro YOSHIDA

Toyoshiro YOSHIDA 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).

  • Publication number: 20220096978
    Abstract: A production method for an organic solvent that contains less metal impurities which when manufacturing a semiconductor device. This production method passes a liquid through a filter cartridge, wherein the filter cartridge is obtained by layering types of base cloths for filtration, wherein the base cloths for filtration are nonwoven fabric obtained by chemically bonding a metal adsorption group to polyolefin fibers, the base cloths for filtration include nonwoven fabric layer A and nonwoven fabric layer B, the nonwoven fabric layer A includes polyolefin fibers to which a sulfonate group is chemically bonded as a metal adsorption group, the nonwoven fabric layer B includes polyolefin fibers bonded thereto as a metal adsorption group at least one selected from the group consisting of an amino group, an N-methyl-D-glucamine group, an iminodiacetate group, an iminodiethanol group, an amidoxime group, a phosphate group, a carboxylate group, and an ethylene diamine triacetate group.
    Type: Application
    Filed: March 3, 2020
    Publication date: March 31, 2022
    Applicant: NISSAN CHEMICAL CORPORATION
    Inventors: Tomoya OHASHI, Toyoshiro YOSHIDA, Suguru SASSA
  • Publication number: 20210397091
    Abstract: A method for producing a coating film-forming composition for lithography, including a step for passing a liquid through a filter cartridge. The filter cartridge is obtained by layering more than one type of filtration base fabrics or winding same around a hollow inner tube, wherein: the fabrics are non-woven fabrics in which metal-adsorbing groups are chemically bonded to polyolefin fibers; the fabrics contain non-woven fabric layers A and B; layer A is configured from polyolefin fibers to which sulfonic acid groups are chemically bonded as metal-adsorbing groups; and layer B is configured from polyolefin fibers to which at least one type selected from among amino groups, N-methyl-D-glucamine groups, iminodiacetic acid groups, iminodiethanol groups, amidoxime groups, phosphoric acid groups, carboxylic acid groups and ethylenediamine triacetic acid groups chemically bonded as metal-adsorbing groups. Thus, the amount of metal impurities that are the cause of minute defects on a wafer can be reduced.
    Type: Application
    Filed: December 18, 2019
    Publication date: December 23, 2021
    Applicant: NISSAN CHEMICAL CORPORATION
    Inventors: Tomoya OHASHI, Toyoshiro YOSHIDA, Suguru SASSA