Patents Examined by Sim J. Lee
  • Patent number: 6544715
    Abstract: A positive photoresist composition for far ultraviolet ray exposure improved in standard developing solution suitability, good in defocus latitude depended on line pitch of a resist pattern formed and excellent in sensitivity to a light source of shorter wavelength, which comprises (i) a compound capable of generating an acid by irradiation of actinic light or radiation; and (ii) a resin containing (a) repeating units each having an alkali-soluble group protected with at least one specific group containing an alicyclic hydrocarbon structure, (b) repeating units having, for example, lactone rings, and (c) repeating units derived from (meth)acrylic acid, the content of the repeating units of (c) being from 5 mol % to 18 mol % based on the total repeating units of the resin, and the resin being decomposable by action of an acid to increase its solubility in an alkali solution.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: April 8, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kenichiro Sato, Kunihiko Kodama, Toshiaki Aoai
  • Patent number: 6333137
    Abstract: A photopolymerizable composition for making screen printing stencils. The composition comprises polyvinyl alcohol having at least one photocrosslinkable group appended thereto. At least one metal salt, wherein the metal is selected from: aluminum, zinc, chromium, zirconium, titanium, tin or iron, is added to the composition. The metal salt is used to improve water resistance of a screen printing image that is prepared from the photopolymerizable composition.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: December 25, 2001
    Assignee: Sericol Limited
    Inventors: Peter Dickinson, Nicholas R. Collins