Patents by Inventor Tetsuo Kurokawa

Tetsuo Kurokawa 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).

  • Photosensitive resin compositions, cured films thereof, and circuit substrates
    Patent number: 6156462
    Abstract: For instance, when a washing-free yet low-residue type of flux is coated on a solder resist film, soldering can be carried out while no solder balls remain on a circuit substrate.A photosensitive resin composition comprises a photopolymerizable and photosensitive resin having at least one of a carboxyl group and an onium group, a photopolymerizable reactive diluent, a photopolymerization initiator, a thermosetting component, and an inorganic powder having an average particle size of 2 .mu.m to 20 .mu.m. A cured film thereof is used as a solder resist film for circuit substrate fabrication.A washing-free yet low-residue type of flux is so uniformly coated on the solder resist film that soldering can be carried out in the absence of any solder ball.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: December 5, 2000
    Assignee: Tamura Kaken Co., Ltd.
    Inventors: Makoto Yanagawa, Rinzo Tachibana, Hiroshi Yamamoto, Tetsuji Ishikawa, Tetsuo Kurokawa, Kohichi Ishida
  • Photosensitive resin compositions, cured films thereof, and circuit boards
    Patent number: 5853957
    Abstract: For instance, when a washing-free yet low-residue type of flux is coated on a solder resist film, soldering can be carried out while no solder balls remain on a circuit substrate.A photosensitive resin composition comprises a photopolymerizable and photosensitive resin having at least one of a carboxyl group and an onium group, a photopolymerizable reactive diluent, a photopolymerization initiator, a thermosetting component, and an inorganic powder having an average particle size of 2 .mu.m to 20 .mu.m. A cured film thereof is used as a solder resist film for circuit substrate fabrication.A washing-free yet low-residue type of flux is so uniformly coated on the solder resist film that soldering can be carried out in the absence of any solder ball.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: December 29, 1998
    Assignee: Tamura Kaken Co., Ltd
    Inventors: Makoto Yanagawa, Rinzo Tachibana, Hiroshi Yamamoto, Tetsuji Ishikawa, Tetsuo Kurokawa, Kohichi Ishida
  • Mask for printing solder paste
    Patent number: 5593080
    Abstract: A mask for printing solder paste includes a mask plate, and first mask holes which are formed in the mask plate and have a first size, and second mask holes which are formed in the mask plate and have a second size smaller than the first size. The mask plate has a first region having the first mask holes, and a second region having the second mask holes. The mask plate has a first thickness in the first region, and a second thickness in the second region. The second thickness is smaller than the first thickness.
    Type: Grant
    Filed: June 12, 1995
    Date of Patent: January 14, 1997
    Assignee: Fujitsu Limited
    Inventors: Yasuhiro Teshima, Tetsuo Kurokawa