Patents by Inventor Kunihito Takaura

Kunihito Takaura 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: 8961709
    Abstract: A solder paste using a Sn—Ag base, Sn—Cu base, or similar alloy powder has a high melting point, so it causes thermal damage to electronic devices. Sn—Ag—In base lead-free solder alloys having a low melting temperature have been studied, but they are difficult to use because they cause much occurrence of chips standing up during reflow. The present invention forms a solder paste by separating a Sn—Ag—In base lead-free solder into first and second solder alloy powders for which the difference in their peak temperatures measured by differential thermal analysis is at least 10° C. and blends the mixed powders with a flux.
    Type: Grant
    Filed: March 9, 2004
    Date of Patent: February 24, 2015
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Kunihito Takaura, Kaichi Tsuruta, Hiroshi Kawanakago, Hiroshi Takahashi
  • Patent number: 6926849
    Abstract: A solder paste comprising a powder of a Zn-containing Sn-based, lead-free solder mixed with an activator-containing rosin-based flux to which 0.5-10.0 wt % of isocyanuric acid or a haloalkyl ester thereof is added can prevent the formation of solder balls and voids during reflow soldering and exhibit good solderability. A solder paste comprising a powder of an Ag- or Zn-containing Sn-based, lead-free solder mixed with an activator-containing rosin-based flux to which 0.01-10.0 wt % of a salicylamide compound also does not exhibit a change in viscosity and exhibits good solderability.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: August 9, 2005
    Assignees: Senju Metal Industry Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Setsuko Tadokoro, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Patent number: 6736907
    Abstract: A lead-free solder paste comprises an Sn—Zn based lead-free solder powder mixed with a flux. The flux contains at least one aromatic hydroxycarboxylic acid selected from the group consisting of aromatic carboxylic acids having one hydroxyl group in a meta position (such as 3-hydroxy-2-methylbenzoic acid) and aromatic carboxylic acids having at least two hydroxyl groups (such as dihydroxynaphthoic acid or dihydroxybenzoic acid) in an amount of 0.1-10.0 mass %. The flux may further include 0.5-20 mass % of an aliphatic hydroxy carboxylic acid (such as hydroxyoleic acid).
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: May 18, 2004
    Assignees: Senju Metal Industry Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Publication number: 20040069974
    Abstract: A solder paste comprising a powder of a Zn-containing Sn-based, lead-free solder mixed with an activator-containing rosin-based flux to which 0.5-10.0 wt % of isocyanuric acid or a haloalkyl ester thereof is added can prevent the formation of solder balls and voids during reflow soldering and exhibit good solderability. A solder paste comprising a powder of an Ag- or Zn-containing Sn-based, lead-free solder mixed with an activator-containing rosin-based flux to which 0.01-10.0 wt % of a salicylamide compound also does not exhibit a change in viscosity and exhibits good solderability.
    Type: Application
    Filed: November 3, 2003
    Publication date: April 15, 2004
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Setsuko Tadokoro, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Publication number: 20030121564
    Abstract: A lead-free solder paste comprises an Sn—Zn based lead-free solder powder mixed with a flux. The flux contains at least one aromatic hydroxycarboxylic acid selected from the group consisting of aromatic carboxylic acids having one hydroxyl group in a meta position (such as 3-hydroxy-2-methylbenzoic acid) and aromatic carboxylic acids having at least two hydroxyl groups (such as dihydroxynaphthoic acid or dihydroxybenzoic acid) in an amount of 0.1-10.0 mass %. The flux may further include 0.5-20 mass % of an aliphatic hydroxy carboxylic acid (such as hydroxyoleic acid).
    Type: Application
    Filed: December 3, 2002
    Publication date: July 3, 2003
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Patent number: 6440228
    Abstract: A solder paste having a powder of a Zn-containing solder alloy such as an Sn—Zn based alloy in admixture with a soldering flux such as a rosin flux is improved by adding from 0.1% to 5.0% by weight of a glycidyl ether compound such as alkyl, alkenyl, or aryl glycidyl ether. The improved solder paste has increased resistance to aging and to concomitant deterioration in solderability caused by reaction of Zn in the solder alloy with ingredients in the flux and has a substantially extended shelf life.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: August 27, 2002
    Assignees: Senju Metal Industry Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Publication number: 20020050305
    Abstract: A solder paste having a powder of a Zn-containing solder alloy such as an Sn—Zn based alloy in admixture with a soldering flux such as a rosin flux is improved by adding from 0.1% to 5.0% by weight of a glycidyl ether compound such as alkyl, alkenyl, or aryl glycidyl ether. The improved solder paste has increased resistance to aging and to concomitant deterioration in solderability caused by reaction of Zn in the solder alloy with ingredients in the flux and has a substantially extended shelf life.
    Type: Application
    Filed: January 31, 2001
    Publication date: May 2, 2002
    Inventors: Toshihiko Taguchi, Kunihito Takaura, Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima
  • Patent number: 6159304
    Abstract: In order to prevent aging of an Sn--Zn system alloy solder paste, 0.5-5% by weight of a compound obtained by adding an ethylene oxide to cyclohexylamine, preferably together with 0.5-5% by weight of a polyoxyethylene alkylamine is added to a flux of said solder paste.
    Type: Grant
    Filed: March 2, 1999
    Date of Patent: December 12, 2000
    Assignees: Matsushita Electric Industrial Co., Ltd., Senju Metal Industry Co., Ltd.
    Inventors: Hiroji Noguchi, Masahiko Hirata, Toshihiko Taguchi, Kunihito Takaura