Patents by Inventor Hiromasa Miyoshi

Hiromasa Miyoshi 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: 11453053
    Abstract: There are provided a bonding material, which can prevent voids from being generated in a silver bonding layer by preventing the entrainment of bubbles during the formation of a coating film even if the coating film is thickened, and a bonding method using the same. The bonding material of a silver paste includes fine silver particles, a solvent and an addition agent, wherein the solvent contains a first solvent of a diol, such as octanediol, and a second solvent which is a polar solvent (preferably one or more selected from the group consisting of dibutyl diglycol, hexyl diglycol, decanol and dodecanol) having a lower surface tension than that of the first solvent and wherein the addition agent is a triol.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: September 27, 2022
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Satoru Kurita, Tatsuro Hori, Keiichi Endoh, Hiromasa Miyoshi
  • Patent number: 10903185
    Abstract: A bonding material includes: fine silver particles having an average primary particle diameter of 1 to 50 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 ?m each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing a primary alcohol solvent and a terpene alcohol solvent; and a dispersant containing a phosphoric acid ester dispersant (or a phosphoric acid ester dispersant and an acrylic resin dispersant), wherein the content of the fine silver particles is in the range of from 5 wt % to 30 wt %, and the content of the silver particles is in the range of from 60 wt % to 90 wt %, the total content of the fine silver particles and the silver particles being not less than 90 wt %, and wherein the bonding material further includes a sintering aid of a monocarboxylic acid having an ether bond.
    Type: Grant
    Filed: May 15, 2015
    Date of Patent: January 26, 2021
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Keiichi Endoh, Koichi Yuzaki, Minami Nagaoka, Hiromasa Miyoshi, Satoru Kurita
  • Patent number: 10821558
    Abstract: There is provided an inexpensive bonding material, which can be easily printed on articles to be bonded to each other and which can suppress the generation of voids in the bonded portions of the articles to be bonded to each other, and a bonding method using the same. In a bonding material of a copper paste which contains a copper powder containing 0.3% by weight or less of carbon and having an average particle diameter of 0.1 to 1 ?m, and an alcohol solvent, such as a monoalcohol, a diol, a triol or a terpene alcohol, the content of the copper powder is in the range of from 80% by weight to 95% by weight, and the content of the alcohol solvent is in the range of from 5% by weight to 20% by weight.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: November 3, 2020
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Keiichi Endoh, Hiromasa Miyoshi, Kimikazu Motomura, Satoru Kurita
  • Patent number: 10543569
    Abstract: A bonding material of a silver paste contains: fine silver particles having an average primary particle diameter of 1 to 200 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as sorbic acid; and a solvent mixed with the fine silver particles, wherein a diol, such as an octanediol, is used as the solvent and wherein a triol having a boiling point of 200 to 300° C., a viscosity of 2,000 to 10,000 mPa·s at 20° C. and at least one methyl group, such as 3-methylbutane-1,2,3-triol or 2-methylbutane-1,2,4-triol, is mixed with the solvent as an addition agent.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: January 28, 2020
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Satoru Kurita, Takashi Hinotsu, Keiichi Endoh, Hiromasa Miyoshi
  • Patent number: 10328534
    Abstract: A bonding material of a silver paste includes: fine silver particles having an average primary particle diameter of 1 to 50 nanometers, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 micrometers, each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing 3 to 7% by weight of an alcohol and 0.3 to 1% by weight of a triol; a dispersant containing 0.5 to 2% by weight of an acid dispersant and 0.01 to 0.1% by weight of phosphate ester dispersant; and 0.01 to 0.
    Type: Grant
    Filed: June 19, 2014
    Date of Patent: June 25, 2019
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Keiichi Endoh, Minami Nagaoka, Satoru Kurita, Hiromasa Miyoshi, Yoshiko Kohno, Akihiro Miyazawa
  • Publication number: 20190118257
    Abstract: There are provided a bonding material, which can prevent voids from being generated in a silver bonding layer by preventing the entrainment of bubbles during the formation of a coating film even if the coating film is thickened, and a bonding method using the same. The bonding material of a silver paste includes fine silver particles, a solvent and an addition agent, wherein the solvent contains a first solvent of a diol, such as octanediol, and a second solvent which is a polar solvent (preferably one or more selected from the group consisting of dibutyl diglycol, hexyl diglycol, decanol and dodecanol) having a lower surface tension than that of the first solvent and wherein the addition agent is a triol.
    Type: Application
    Filed: April 25, 2017
    Publication date: April 25, 2019
    Applicant: Dowa Electronics Materials Co., Ltd.
    Inventors: Satoru Kurita, Tatsuro Hori, Keiichi Endoh, Hiromasa Miyoshi
  • Publication number: 20180331063
    Abstract: A method for joining an electronic part, comprising: inserting a joining silver sheet between an electronic part and a substrate, to which the electronic part is to be joined; and heating them to the temperature range of TA (° C.) or higher and TB (° C.) or lower, under application of a pressure to the electronic part and the substrate to make a contact surface pressure of the electronic part and the silver sheet of from 0.5 to 3 MPa. The joining silver sheet comprises silver particles having a particle diameter of from 1 to 250 nm integrated by sintering, and has a capability of further undergoing sintering on heating and retaining the silver sheet at a temperature range of “TA (° C.) or higher and TB (° C.) or lower satisfying the following expression (1): 270?TA<TB?350.
    Type: Application
    Filed: July 23, 2018
    Publication date: November 15, 2018
    Inventors: Satoru KURITA, Keiichi ENDOH, Hiromasa MIYOSHI
  • Patent number: 9914845
    Abstract: There is produced a fine silver particle dispersing solution which contains: fine silver particles (the content of silver in the fine silver particle dispersing solution is 30 to 90% by weight), which have an average primary particle diameter of 1 to 100 nm and which are coated with an amine having a carbon number of 8 to 12, such as octylamine, serving as an organic protective material; a polar solvent (5 to 70% by weight) having a boiling point of 150 to 300° C.; and an acrylic dispersing agent (1.5 to 5% by weight with respect to the fine silver particles), such as a dispersing agent of at least one of acrylic acid ester and methacrylic acid ester.
    Type: Grant
    Filed: December 4, 2014
    Date of Patent: March 13, 2018
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Takashi Hinotsu, Tomonori Shibayama, Hiromasa Miyoshi
  • Publication number: 20170252874
    Abstract: There is provided an inexpensive bonding material, which can be easily printed on articles to be bonded to each other and which can suppress the generation of voids in the bonded portions of the articles to be bonded to each other, and a bonding method using the same. In a bonding material of a copper paste which contains a copper powder containing 0.3% by weight or less of carbon and having an average particle diameter of 0.1 to 1 ?m, and an alcohol solvent, such as a monoalcohol, a diol, a triol or a terpene alcohol, the content of the copper powder is in the range of from 80% by weight to 95% by weight, and the content of the alcohol solvent is in the range of from 5% by weight to 20% by weight.
    Type: Application
    Filed: August 31, 2015
    Publication date: September 7, 2017
    Inventors: Keiichi Endoh, Hiromasa Miyoshi, Kimikazu Motomura, Satoru Kurita
  • Patent number: 9662748
    Abstract: There is provided a metal nanoparticle dispersion which can be bonded at a lower temperature (for example, 200° C. or less), and enabling to obtain excellent mechanical properties and electric properties of the bonded portion, the metal nanoparticle dispersion, including: metal nanoparticles, with at least a part of a surface of each particle coated with amine A having 8 or more carbon atoms; and a dispersion medium for dispersing the metal nanoparticles, wherein the dispersion medium contains amine B which is primary, secondary, or tertiary amine having 7 or less carbon atoms, and which is linear alkyl amine or alkanol amine.
    Type: Grant
    Filed: April 25, 2014
    Date of Patent: May 30, 2017
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Keiichi Endoh, Hiromasa Miyoshi, Takashi Hinotsu, Satoru Kurita, Yoshiko Kohno
  • Publication number: 20170120395
    Abstract: A bonding material of a silver paste contains: fine silver particles having an average primary particle diameter of 1 to 200 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as sorbic acid; and a solvent mixed with the fine silver particles, wherein a diol, such as an octanediol, is used as the solvent and wherein a triol having a boiling point of 200 to 300° C., a viscosity of 2,000 to 10,000 mPa·s at 20° C. and at least one methyl group, such as 2-methylbutane-2,3,4-triol or 2-methylbutane-1,2,4-triol, is mixed with the solvent as an addition agent.
    Type: Application
    Filed: May 29, 2015
    Publication date: May 4, 2017
    Applicant: Dowa Electronics Materials Co., Ltd.
    Inventors: Satoru Kurita, Takashi Hinotsu, Keiichi Endoh, Hiromasa Miyoshi
  • Publication number: 20170077057
    Abstract: A bonding material includes: fine silver particles having an average primary particle diameter of 1 to 50 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 ?m each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing a primary alcohol solvent and a terpene alcohol solvent; and a dispersant containing a phosphoric acid ester dispersant (or a phosphoric acid ester dispersant and an acrylic resin dispersant), wherein the content of the fine silver particles is in the range of from 5 wt % to 30 wt %, and the content of the silver particles is in the range of from 60 wt % to 90 wt %, the total content of the fine silver particles and the silver particles being not less than 90 wt %, and wherein the bonding material further includes a sintering aid of a monocarboxylic acid having an ether bond.
    Type: Application
    Filed: May 15, 2015
    Publication date: March 16, 2017
    Applicant: Dowa Electronics Materials Co., Ltd.
    Inventors: Keiichi Endoh, Koichi Yuzaki, Minami Nagaoka, Hiromasa Miyoshi, Saturo Kurita
  • Publication number: 20160297982
    Abstract: There is produced a fine silver particle dispersing solution which contains: fine silver particles (the content of silver in the fine silver particle dispersing solution is 30 to 90% by weight), which have an average primary particle diameter of 1 to 100 nm and which are coated with an amine having a carbon number of 8 to 12, such as octylamine, serving as an organic protective material; a polar solvent (5 to 70% by weight) having a boiling point of 150 to 300° C.; and an acrylic dispersing agent (1.5 to 5% by weight with respect to the fine silver particles), such as a dispersing agent of at least one of acrylic acid ester and methacrylic acid ester.
    Type: Application
    Filed: December 4, 2014
    Publication date: October 13, 2016
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Takashi Hinotsu, Tomonori Shibayama, Hiromasa Miyoshi
  • Publication number: 20160254243
    Abstract: A joining silver sheet with high joining strength contains silver particles having a particle diameter of from 1 to 250 nm integrated by sintering, and has a capability of further undergoing sintering on heating and retaining the silver sheet at a temperature range of from TA to TB (° C.) satisfying 270 £ TA<TB £ 350. A method of making the silver sheet includes subjecting a coated film of a silver paste containing silver powder containing silver particles having a particle diameter of from 1 to 250 nm, and a dispersion medium that undergoes volatilization in a temperature range of 200° C. or lower, which are mixed with each other, to a heat treatment at a temperature range, at which no sintering occurs, and then baking at a temperature of from 170 to 250° C. under application of a pressure of from 5 to 35 MPa.
    Type: Application
    Filed: October 6, 2014
    Publication date: September 1, 2016
    Inventors: Satoru KURITA, Keiichi ENDOH, Hiromasa MIYOSHI
  • Publication number: 20160136763
    Abstract: A bonding material of a silver paste includes: fine silver particles having an average primary particle diameter of 1 to 50 nanometers, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 micrometers, each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing 3 to 7% by weight of an alcohol and 0.3 to 1% by weight of a triol; a dispersant containing 0.5 to 2% by weight of an acid dispersant and 0.01 to 0.1% by weight of phosphate ester dispersant; and 0.01 to 0.
    Type: Application
    Filed: June 19, 2014
    Publication date: May 19, 2016
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Keiichi Endoh, Minami Nagaoka, Satoru Kurita, Hiromasa Miyoshi, Yoshiko Kohno, Akihiro Miyazawa
  • Publication number: 20160121435
    Abstract: A metal paste for joining includes aggregates of metal nanoparticles and a solvent, and an average particle size of the aggregates is 1 ?m or more.
    Type: Application
    Filed: May 15, 2014
    Publication date: May 5, 2016
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masashi FURUKAWA, Hiroomi KOBAYASHI, Yoshinori SHIBATA, Keisuke UCHIDA, Hiromasa MIYOSHI, Keiichi ENDOH, Satoru KURITA, Minami NAGAOKA
  • Publication number: 20160101486
    Abstract: There is provided a metal nanoparticle dispersion which can be bonded at a lower temperature (for example, 200° C. or less), and enabling to obtain excellent mechanical properties and electric properties of the bonded portion, the metal nanoparticle dispersion, including: metal nanoparticles, with at least a part of a surface of each particle coated with amine A having 8 or more carbon atoms; and a dispersion medium for dispersing the metal nanoparticles, wherein the dispersion medium contains amine B which is primary, secondary, or tertiary amine having 7 or less carbon atoms, and which is linear alkyl amine or alkanol amine.
    Type: Application
    Filed: April 25, 2014
    Publication date: April 14, 2016
    Inventors: Keiichi ENDOH, Hiromasa MIYOSHI, Takashi HINOTSU, Satoru KURITA, Yoshiko KOHNO
  • Patent number: 8673049
    Abstract: A silver nanoparticle composition is provided which is possible to be sintered through sintering at a low temperature in a short time and to form silver electro conductive film and wiring which is favorable for adhesion to a substrate and low in resistance, and articles using the same are provided. The silver nanoparticle composition is provided, wherein a main component of a solvent is water, a pH of the composition is within a range of 5.3 to 8.0, a silver nanoparticle included in the composition is protected by an organic acid or a derivative thereof, and the content of the organic acid or the derivative thereof with respect to silver is 2 to 20% by mass.
    Type: Grant
    Filed: August 27, 2010
    Date of Patent: March 18, 2014
    Assignees: DOWA Electronics Materials Co., Ltd., PChem Associates, Inc.
    Inventors: Gregory A. Jablonski, Michael A. Mastropietro, Kimitaka Sato, Hiromasa Miyoshi, Hidefumi Fujita
  • Publication number: 20120177897
    Abstract: A silver nanoparticle composition is provided which is possible to be sintered through sintering at a low temperature in a short time and to form silver electro conductive film and wiring which is favorable for adhesion to a substrate and low in resistance, and articles using the same are provided. The silver nanoparticle composition is provided, wherein a main component of a solvent is water, a pH of the composition is within a range of 5.3 to 8.0, a silver nanoparticle included in the composition is protected by an organic acid or a derivative thereof, and the content of the organic acid or the derivative thereof with respect to silver is 2 to 20% by mass.
    Type: Application
    Filed: August 27, 2010
    Publication date: July 12, 2012
    Applicants: PCHEM ASSOCIATES, INC.,, DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Gregory A. Jablonski, Michael A. Mastropietro, Kimitaka Sato, Hiromasa Miyoshi, Hidefumi Fujita
  • Patent number: 7235119
    Abstract: Copper particle clusters constituting a powder suitable for making a conductive paste are provided that are individually composed of not fewer than two and not more than 20 unit particles joined through neck portions. A conductive paste made from the powder is excellent in conductivity. A conductive filler for conductive paste is provided that consists essentially of a mixture of copper particle clusters A individually composed of two or more unit particles joined through neck portions and spherical metallic particles B of smaller diameter than the particles A. A conductive paste made from the filler is low in viscosity and excellent in conductivity.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: June 26, 2007
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Kazushi Sano, Yoshihiro Okada, Hiromasa Miyoshi, Yoshiomi Takada