Patents by Inventor Kenji Uhara

Kenji Uhara 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: 7452610
    Abstract: A multi-layer polyimide film including two or more laminated polyimide film layers is provided, with at least one of the two or more polyimide film layers is obtained by imidizing a polyamic acid derived from the reaction of at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4?-diaminobiphenyl represented by the following formula, wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof. Methods for obtaining a multi-layer polyimide film laminate can exhibit a peel strength of 10N/cm when laminated to a metal foil using an adhesive and can have a water absorption value of less than 3.0 weight percent.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: November 18, 2008
    Assignee: Du Pont Toray Company Limited
    Inventor: Kenji Uhara
  • Patent number: 7273661
    Abstract: This invention is directed to polyimide films having a carbon nanotube filler to provide a surface resistivity in a range from 50 ohm/square to 1.0×1015 ohms/square. The electrically conductive polyimides of the present invention have an excellent balance of properties relative to conventional polyimides having a conductive filler, due at least in part to the film's water content, degree of imidization and polymer orientation.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: September 25, 2007
    Assignee: DuPont Toray Co., Ltd.
    Inventors: Hideki Moriyama, Kenji Uhara
  • Publication number: 20070003773
    Abstract: A multi-layer polyimide film including two or more laminated polyimide film layers is provided, with at least one of the two or more polyimide film layers is obtained by imidizing a polyamic acid derived from the reaction of at least one aromatic diamine containing 1-100 mol percent of carboxy-4,4?-diaminobiphenyl represented by the following formula, wherein m and n represent integers of 4 or less, including 0, and (m+n) is an integer of 1 or greater, and at least one aromatic tetracarboxylic dianhydride or a derivative thereof. Methods for obtaining a multi-layer polyimide film laminate can exhibit a peel strength of 10N/cm when laminated to a metal foil using an adhesive and can have a water absorption value of less than 3.0 weight percent.
    Type: Application
    Filed: June 29, 2005
    Publication date: January 4, 2007
    Inventor: Kenji Uhara
  • Publication number: 20060009615
    Abstract: A polyamic acid obtained by the reaction of an aromatic diamine containing 1-100 mol percent of a carboxy-4,4?-diaminobiphenyl and an aromatic tetracarboxylic dianhydride or derivative thereof is provided. A polyimide is obtained from the imidization of the polyamic acid. Methods for obtaining the polyamic acid, the polyimide, a polyimide film, and a polyimide film-metal laminate are also disclosed. The polyimide film-metal laminate has a high peel strength of at least 10N/cm when laminated to a metal foil using an adhesive, and as such can generally be used as a flexible circuit substrate.
    Type: Application
    Filed: June 29, 2005
    Publication date: January 12, 2006
    Inventor: Kenji Uhara
  • Patent number: 6916544
    Abstract: A laminate having improved resistance to separation failure when incorporated into a flexible circuit structure. The laminate comprising a highly bondable polyimide and is preferably formed from a polyamic acid comprising a tetracarboxylic acid component, a diamine component, and 0.1 to 5.0 mole % of a dicarboxylic acid component, with respect to the tetracarboxylic acid component, and wherein the adhesive strength of the laminate is greater than 10 N/cm, and more preferably greater than 19 N/cm.
    Type: Grant
    Filed: May 17, 2002
    Date of Patent: July 12, 2005
    Assignees: E. I. du Pont de Nemours and Company, DuPont Toray Co. Ltd.
    Inventors: Hideki Moriyama, Kenji Uhara, Meredith L. Dunbar, James R. Edman
  • Patent number: 6908685
    Abstract: The invention provides a polyimide film manufactured from a polyamic acid prepared from pyromellitic dianhydride in combination with 10 to 60 mol % of phenylenediamine and 40 to 90 mol % of 3,4?-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: June 21, 2005
    Assignees: E. I. du Pont de Nemours and Company, DuPont-Toray Co. Ltd.
    Inventors: Kenji Uhara, Kouichi Sawasaki, Naofumi Yasuda, Brian C. Auman, John D. Summers
  • Patent number: 6828390
    Abstract: A high modulus, dimensionally stable film formed via an interpenetrating polyimide network of two polyimide structures, interlocked and bonded on a molecular level. The polyimide components are made from a dianhydride and a diamine. The dianhydrides used are tetravalent aromatic structures represented by where X is a divalent organic group selected from among —CO—, —O—, —S—, —SO2—, —CH2—, —C(CH3)2—, and —C(CF3)2— and diamines used are divalent aromatic structure represented by wherein Y is a divalent organic group selected from the group consisting of —CO—, —O—, —S—, —SO2—, —CH2—, —C(CH3)2—, and —C(CF3)2—. The end capping agent is a carboxylic anhydride or a silylating agent. The second polyimide is polymerized in the presence of the first polymer thus forming a single phase system.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: December 7, 2004
    Assignee: E.I. du Pont de Nemours and Company
    Inventor: Kenji Uhara
  • Publication number: 20040071990
    Abstract: This invention is directed to polyimide films having a carbon nanotube filler to provide a surface resistivity in a range from 50 ohm/square to 1.0×1015 ohms/square. The electrically conductive polyimides of the present invention have an excellent balance of properties relative to conventional polyimides having a conductive filler, due at least in part to the film's water content, degree of imidization and polymer orientation.
    Type: Application
    Filed: July 2, 2003
    Publication date: April 15, 2004
    Inventors: Hideki Moriyama, Kenji Uhara
  • Publication number: 20040010113
    Abstract: The invention provides a polyimide film manufactured from a polyamic acid prepared from pyromellitic dianhydride in combination with 10 to 60 mol % of phenylenediamine and 40 to 90 mol % of 3,4′-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Application
    Filed: January 28, 2003
    Publication date: January 15, 2004
    Inventors: Kenji Uhara, Kouichi Sawasaki, Naofumi Yasuda, Brian C Auman, John D Summers
  • Publication number: 20030236359
    Abstract: A high modulus, dimensionally stable film formed via an interpenetrating polyimide network of two polyimide structures, interlocked and bonded on a molecular level. The polyimide components are made from a dianhydride and a diamine.
    Type: Application
    Filed: December 30, 2002
    Publication date: December 25, 2003
    Inventor: Kenji Uhara
  • Publication number: 20030215654
    Abstract: A laminate having improved resistance to separation failure when incorporated into a flexible circuit structure. The laminate comprising a highly bondable polyimide and is preferably formed from a polyamic acid comprising a tetracarboxylic acid component, a diamine component, and 0.1 to 5.0 mole % of a dicarboxylic acid component, with respect to the tetracarboxylic acid component, and wherein the adhesive strength of the laminate is greater than 10 N/cm, and more preferably greater than 19 N/cm.
    Type: Application
    Filed: May 17, 2002
    Publication date: November 20, 2003
    Inventors: Hideki Moriyama, Kenji Uhara, Meredith L. Dunbar, James R. Edman
  • Patent number: 6555238
    Abstract: A polyimide film is manufactured from a random copolymeric, block copolymeric or interpenetrating polymer network-type polyamic acid prepared from pyromellitic dianhydride in combination with 22 to 78 mol % of 4,4′-oxydianiline and 22 to 78 mol % of 3,4′-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: April 29, 2003
    Assignee: DuPont-Toray Co. Ltd.
    Inventors: Kenji Uhara, Naofumi Yasuda, Kouichi Sawasaki
  • Patent number: 6548179
    Abstract: A polyimide film is produced by copolymerizing pyromellitic dianhydride in combination with phenylenediamine, methylenedianiline and 3,4′-oxydianiline in a specific molar ratio. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Grant
    Filed: August 9, 2001
    Date of Patent: April 15, 2003
    Assignee: DuPont-Toray Co., Ltd.
    Inventors: Kenji Uhara, Naofumi Yasuda, Kouichi Sawasaki
  • Publication number: 20020045033
    Abstract: A polyimide film is produced by copolymerizing pyromellitic dianhydride in combination with phenylenediamine, methylenedianiline and 3,4′-oxydianiline in a specific molar ratio. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Application
    Filed: August 9, 2001
    Publication date: April 18, 2002
    Inventors: Kenji Uhara, Naofumi Yasuda, Kouichi Sawasaki
  • Publication number: 20020045054
    Abstract: A polyimide film is manufactured from a random copolymeric, block copolymeric or interpenetrating polymer network-type polyamic acid prepared from pyromellitic dianhydride in combination with 22 to 78 mol % of 4,4′-oxydianiline and 22 to 78 mol % of 3,4′-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.
    Type: Application
    Filed: August 10, 2001
    Publication date: April 18, 2002
    Inventors: Kenji Uhara, Naofumi Yasuda, Kouichi Sawasaki
  • Patent number: 6277495
    Abstract: A polyimide film of birefringence less than 0.01 is formed by drawing a copolymerized polyimide comprising a block component and a random component which are molecularly bonded, wherein the block component of copolymerized polyimide comprises an aromatic diamine compound having a rigid structure and an aromatic tetracarboxylic acid compound and wherein the random component of copolymerized polyimide comprises an aromatic diamine compound having a flexible structure and at least two aromatic tetracarboxylic acid components. The resulting polyimide film has high elasticity, a low thermal expansion equivalent to that of metal and low water absorbing properties. A method for its manufacture and a metal laminated plate having improved curl properties in which the polyimide is used as the base material are also disclosed.
    Type: Grant
    Filed: July 14, 1998
    Date of Patent: August 21, 2001
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Koichi Sawasaki, Kenji Uhara, Michihiro Kubo