Patents by Inventor Tatsuki Kitayama

Tatsuki Kitayama 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).

  • Graft copolymers, process for the preparation thereof and ionizing radiation sensitive resist using such copolymers
    Patent number: 4559389
    Abstract: Solvent-soluble copolymers having a number average molecular weight of about 1,000 to about 1,000,000 and comprising recurring units of the following formulae (I) and (II) (case A) or recurring unit of the following formulae (I), (II) and (III) (case B) or solvent-soluble graft copolymers having a number average molecular weight of about 1,500 to about 2,000,000 and comprising recurring units of the following formulae (I), (II) and/or (II'), and (IV) (case C) or recurring units of the following formulae (I), (II) and/or (II'), (III) and (IV) (case D), said recurring units being combined to form the main alkylene chain, wherein in the cases A and B the amount of the formula (I) unit is about 3 to 60 mol % of the total amount of the whole units, and in the cases C and D the amount of the formula (I) unit is about 5 to 60 mol % of the total amount of the units of formulae (I), (II) and/or (II'), and (IV), and in the cases B and D the amount of the formula (III) unit is about 1 to 40 mol % of the total amount of
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: December 17, 1985
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Koichi Hatada, Yoshio Okamoto, Tatsuki Kitayama
  • Copolymers, process for the preparation thereof and ionizing radiation sensitive resist using such copolymers
    Patent number: 4523000
    Abstract: Solvent-soluble copolymers having a number average molecular weight of about 1,000 to about 1,000,000 and comprising recurring units of the following formulae (I) and (II) (case A) or recurring unit of the following formulae (I), (II) and (III) (case B) or solvent-soluble graft copolymers having a number average molecular weight of about 1,500 to about 2,000,000 and comprising recurring units of the following formulae (I), (II) and/or (II'), and (IV) (case C) or recurring units of the following formulae (I), (II) and/or (II'), (III) and (IV) (case D), said recurring units being ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 represents independently hydrogen, a straight or branched chain alkyl group having 1 to 4 carbon atoms or a halogen; R.sub.4 represents hydrogen or a straight or branched chain alkyl group having 1 to 10 carbon atoms; R.sub.5 represents an alkyl group having 1 to 6 carbon atoms, a phenyl group or a benzyl group; R.sub.6 represents hydrogen or a methyl group; R.sub.
    Type: Grant
    Filed: October 28, 1983
    Date of Patent: June 11, 1985
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Koichi Hatada, Yoshio Okamoto, Tatsuki Kitayama