Patents by Inventor Masahiro Oura

Masahiro Oura 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).

  • Publication number: 20120111622
    Abstract: The present invention relates to a double-sided pressure-sensitive adhesive tape or sheet for use in a wiring circuit board, which includes a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive composition comprising an acrylic polymer and a tackifier resin containing a phenolic hydroxyl group; and a release liner comprising a releasing treatment layer formed of a silicone release agent. The double-sided pressure-sensitive adhesive tape or sheet of the invention has a good adhesiveness and, even after a high-temperature step, it is capable of exerting an excellent anti-repulsion property. Further, since the release liner can be easily peeled off even after the high-temperature step, the workability is excellent and the productivity is improved.
    Type: Application
    Filed: January 19, 2012
    Publication date: May 10, 2012
    Applicant: NITTO DENKO CORPORATION
    Inventors: Noritsugu DAIGAKU, Takahiro Nonaka, Masahiro Oura
  • Publication number: 20120111612
    Abstract: The present invention provides a thermosetting adhesive tape or sheet having a thermosetting adhesive layer, which can be stored stably at room temperature, and, when thermally cured, can exert excellent adhesiveness and high thermal stability after exposure to heat and moist, because the resin in the adhesive rapidly reacts upon curing. The thermosetting adhesive tape or sheet according to the present invention includes a thermosetting adhesive layer which has a gel fraction of less than 70%, a difference in gel fraction between before and after storage at 40° C. for 7 days [(gel fraction after storage at 40° C. for 7 days)?(gel fraction before storage at 40° C. for 7 days)] of 15% or less, and a gel fraction after curing at 150° C. for 1 hour of 90% or more.
    Type: Application
    Filed: June 23, 2010
    Publication date: May 10, 2012
    Applicant: Nitto Denko Corporation
    Inventors: Rie Kuwahara, Masahiro Oura, Takahiro Nonaka, Noritsugu Daigaku
  • Patent number: 7927697
    Abstract: The present invention relates to a double-sided pressure-sensitive adhesive tape or sheet for wiring circuit board, which comprises a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive composition containing an acrylic polymer and a chain transfer substance, in which the pressure-sensitive adhesive layer has characteristics that a gel fraction in the initial stage is from 40 to 70% by weight, and a difference between a gel fraction (% by weight) of the pressure-sensitive adhesive layer after the following solder reflow step and the gel fraction (% by weight) of the pressure-sensitive adhesive layer in the initial stage is 10 or less. The solder reflow step satisfies the following heat treatment conditions. Surface temperature of the double-sided pressure-sensitive adhesive tape or sheet reaches 175±10° C. within 130 to 180 seconds, the surface temperature reaches 230±10° C. within 200 to 250 seconds, the surface temperature reaches 255±15° C.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: April 19, 2011
    Assignee: Nitto Denko Corporation
    Inventors: Takahiro Nonaka, Miyoko Ikishima, Noritsugu Daigaku, Masahiro Oura, Masahiko Ando
  • Publication number: 20100209649
    Abstract: Disclosed is a double-coated pressure-sensitive adhesive sheet which includes at least a pressure-sensitive adhesive unit including a plastic base film and, present on or above both surfaces thereof, pressure-sensitive adhesive layers; and non-silicone release liners present on both surfaces of the pressure-sensitive adhesive unit. The pressure-sensitive adhesive layers are each formed from an acrylic polymer containing, as essential monomer components, an alkyl (meth)acrylate whose alkyl moiety being a linear or branched-chain alkyl group having 2 to 14 carbon atoms and a polar-group-containing monomer. The pressure-sensitive adhesive unit has a thickness of 60 to 160 ?m, and each of the two pressure-sensitive adhesive layers of the pressure-sensitive adhesive unit has a thickness of 20 ?m or more. The adhesive sheet excels in processability and fittability around bumps and is usable for fixing a flexible printed circuit board or for fixing a hard disk drive component.
    Type: Application
    Filed: February 17, 2010
    Publication date: August 19, 2010
    Applicant: NITTO DENKO CORPORATION
    Inventors: Rie Kuwahara, Takahiro Nonaka, Noritsugu Daigaku, Masahiro Oura
  • Publication number: 20100183872
    Abstract: Disclosed is a double-coated pressure-sensitive adhesive sheet for fixing a flexible printed circuit board, which includes at least a pressure-sensitive adhesive unit including a plastic base film having a thickness of 13 ?m or less, and pressure-sensitive adhesive layers on both sides of the plastic base film. The pressure-sensitive adhesive layers are formed from an acrylic polymer containing, as essential monomer components, a polar-group-containing monomer and an alkyl (meth)acrylate whose alkyl moiety being a linear or branched-chain alkyl group having 2 to 14 carbon atoms. The pressure-sensitive adhesive unit has a thickness of 60 ?m or less, the double-coated pressure-sensitive adhesive sheet shows an outgassing of 1 ?g/cm2 or less when heated at 120° C. for 10 minutes, and shows a split distance (lifting) of 1.5 mm or less.
    Type: Application
    Filed: January 7, 2010
    Publication date: July 22, 2010
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takahiro Nonaka, Noritsugu Daigaku, Masahiro Oura
  • Publication number: 20090263606
    Abstract: The present invention provides a thermosetting adhesive or pressure-sensitive adhesive tape or sheet including: a thermosetting adhesive or pressure-sensitive adhesive layer formed of a thermosetting adhesive or pressure-sensitive adhesive composition containing an acrylic polymer (X) constituted of, as essential monomer components, an alkyl (meth)acrylate (a) in which the alkyl moiety thereof has from 2 to 14 carbon atoms and a cyano group-containing monomer (b), and a phenol resin (Y); and provided on at least one surface of the thermosetting adhesive or pressure-sensitive adhesive layer, a release liner including a plastic film substrate and a release layer provided on at least one side of the plastic film substrate, the release layer containing low density polyethylene as a major component and having a thickness of 5 ?m or more and less than 20 ?m.
    Type: Application
    Filed: April 20, 2009
    Publication date: October 22, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takahiro NONAKA, Noritsugu DAIGAKU, Rie KUWAHARA, Masahiro OURA, Sadaji SUTOU
  • Patent number: 7534478
    Abstract: The release liner includes a release layer constituted of at least one polyolefin resin, wherein the release layer has surface irregularities. The surface irregularities of the release layer may be constituted of recesses and protrusions which are irregularly different in shape and have been disposed in irregular arrangement. The release layer preferably has a surface roughness Ra of 1-3 ?m. As the polyolefin resin constituting the release layer can be used at least one polyolefin resin selected from the group consisting of polyethylenes, polypropylene, polybutenes, poly(4-methyl-1-pentene), and copolymers of ethylene with one or more ?-olefins having 3-10 carbon atoms.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: May 19, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Takahiro Nonaka, Shinji Inokuchi, Masahiro Oura
  • Publication number: 20080248231
    Abstract: The present invention relates to a double-sided pressure-sensitive adhesive tape or sheet for use in a wiring circuit board, which includes a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive composition comprising an acrylic polymer and a tackifier resin containing a phenolic hydroxyl group; and a release liner comprising a releasing treatment layer formed of a silicone release agent. The double-sided pressure-sensitive adhesive tape or sheet of the invention has a good adhesiveness and, even after a high-temperature step, it is capable of exerting an excellent anti-repulsion property. Further, since the release liner can be easily peeled off even after the high-temperature step, the workability is excellent and the productivity is improved.
    Type: Application
    Filed: April 9, 2008
    Publication date: October 9, 2008
    Applicant: NITTO DENKO CORPORATION
    Inventors: Noritsugu Daigaku, Takahiro Nonaka, Masahiro Oura
  • Publication number: 20070237949
    Abstract: The present invention relates to a double-sided pressure-sensitive adhesive tape or sheet for wiring circuit board, which comprises a pressure-sensitive adhesive layer formed by a pressure-sensitive adhesive composition containing an acrylic polymer and a chain transfer substance, in which the pressure-sensitive adhesive layer has characteristics that a gel fraction in the initial stage is from 40 to 70% by weight, and a difference between a gel fraction (% by weight) of the pressure-sensitive adhesive layer after the following solder reflow step and the gel fraction (% by weight) of the pressure-sensitive adhesive layer in the initial stage is 10 or less. The solder reflow step satisfies the following heat treatment conditions. Surface temperature of the double-sided pressure-sensitive adhesive tape or sheet reaches 175±10° C. within 130 to 180 seconds, the surface temperature reaches 230±10° C. within 200 to 250 seconds, the surface temperature reaches 255±15° C.
    Type: Application
    Filed: April 11, 2007
    Publication date: October 11, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Takahiro Nonaka, Miyoko Ikishima, Noritsugu Daigaku, Masahiro Oura, Masahiko Ando
  • Publication number: 20050266195
    Abstract: The release liner includes a release layer constituted of at least one polyolefin resin, wherein the release layer has surface irregularities. The surface irregularities of the release layer may be constituted of recesses and protrusions which are irregularly different in shape and have been disposed in irregular arrangement. The release layer preferably has a surface roughness Ra of 1-3 ?m. As the polyolefin resin constituting the release layer can be used at least one polyolefin resin selected from the group consisting of polyethylenes, polypropylene, polybutenes, poly(4-methyl-1-pentene), and copolymers of ethylene with one or more ?-olefins having 3-10 carbon atoms.
    Type: Application
    Filed: May 16, 2005
    Publication date: December 1, 2005
    Inventors: Takahiro Nonaka, Shinji Inokuchi, Masahiro Oura
  • Patent number: 6299975
    Abstract: A pressure-sensitive adhesive sheet prepared by coating a composition containing a) 100 parts by weight of monomers composed of from 70 to 100% by weight of a (meth)acrylic acid alkyl ester, said alkyl group having from 2 to 14 carbon atoms, and from 0 to 30% by weight of a monoethylenically unsaturated monomer copolymerizing therewith, b) from 0.1 to 5 parts by weight of a radical chain inhibitor, c) from 0.02 to 5 parts by weight of a polyfunctional (meth)acrylate as a crosslinking agent, d) from 0.005 to 1 part by weight of a photopolymerization initiator, and e) from 0.01 to 10 parts by weight of a silane coupling agent, on a releasing-treated film having a good surface smoothness and photopolymerizing the coated layer to form a pressure-sensitive adhesive layer having a haze value of 1% or lower and a total light transmission of at least 90%.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: October 9, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Hitoshi Takahira, Masahiro Oura, Takao Yoshikawa, Hiroaki Kishioka
  • Patent number: 6284368
    Abstract: Adhesive sheets using an acrylic pressure-sensitive flame-retardant adhesive having excellent properties such as adhesive force and holding power at high temperature and also having a self fire-extinguishing property which instantaneously extinguishes fire, i.e., a flame-retardance, are provided. A photopolymerizable composition comprising a) 100 parts by weight of a monomer (or the oligomer thereof) comprising 70 to 100% by weight of a (meth)acrylic acid alkyl ester having on the average a carbon number of 2 to 14 in the alkyl group and 30 to 0% by weight of a monoethylenically unsaturated monomer copolymerizable with the ester, b) 0.02 to 5 parts by weight of a polyfunctional (meth)acrylate as a crosslinking agent, c) 0.01 to 5 parts by weight of a photopolymerization initiator, and d) 10 to 180 parts by weight of a flame retardant having a melting point of at least 60° C.
    Type: Grant
    Filed: September 21, 1998
    Date of Patent: September 4, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Shigeki Muta, Takao Yoshikawa, Masahiro Oura
  • Publication number: 20010008689
    Abstract: Adhesive sheets using an acrylic pressure-sensitive flame-retardant adhesive having excellent properties such as adhesive force and holding power at high temperature and also having a self fire-extinguishing property which instantaneously extinguishes fire, i.e., a flame-retardance, are provided. A photopolymerizable composition comprising (a) 100 parts by weight of a monomer (or the oligomer thereof) comprising 70 to 100% by weight of a (meth)acrylic acid alkyl ester having on the average a carbon number of 2 to 14 in the alkyl group and 30 to 0% by weight of a monoethylenically unsaturated monomer copolymerizable with the ester, (b) 0.02 to 5 parts by weight of a polyfunctional (meth)acrylate as a crosslinking agent, (c) 0.01 to 5 parts by weight of a photopolymerization initiator, and (d) 10 to 180 parts by weight of a flame retardant having a melting point of at least 60° C.
    Type: Application
    Filed: September 21, 1998
    Publication date: July 19, 2001
    Inventors: SHIGEKI MUTA, TAKAO YOSHIKAWA, MASAHIRO OURA
  • Patent number: 6261685
    Abstract: An adhesive sheet not tacky at ordinary temperatures, exhibiting strong adhesion and high heat resistance by heating under low pressure for a short period of time, having no problem of adhesive protrusion and excellent in storage stability, which comprises a base material having provided on one side or both sides thereof at least one layer of a thermosetting adhesive comprising (1) a non-tacky polymer of a monomer mixture comprising from 70% to 99% by weight of a (meth)acrylic ester represented by formula (I), a homopolymer of which has a glass transition temperature of −30° C.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: July 17, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Kazuhito Hosokawa, Masahiro Oura
  • Patent number: 6211261
    Abstract: A thermosetting pressure-sensitive adhesive which can obtain the high rate of polymerization without a decrease in the molecular weight by photopolymerization, thereby show the tackiness at ordinary temperatures to permit easy temporary adhesion to an adherend, can be cured by heating for a short period of time to exhibit strong adhesive strength and high heat resistance, and is excellent in storage stability before heating, comprising a photopolymerized product of a composition comprising a) 100 parts by weight of a monomer mixture comprising 70% to 99% by weight of an alkyl (meth)acrylate whose alkyl group has 2 to 14 carbon atoms on average, and 1% to 30% by weight of a monoethylenic unsaturated acid copolymerizable therewith based on the monomer mixture, b) 0.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: April 3, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Kazuhito Hosokawa, Masahiro Oura
  • Patent number: 6207272
    Abstract: A peelable heat-conductive and pressure-sensitive adhesive is disclosed, which comprises: (a) 100 parts by weight of a polymer produced from a monomer mixture comprising from 70 to 100% by weight of one or more alkyl (meth)acrylates in which the alkyl groups on the average have 2 to 14 carbon atoms and from 0 to 30% by weight of one or more monoethylenic monomers copolymerizable therewith, each based on the amount of the monomer mixture; (b) from 20 to 400 parts by weight of a plasticizer having a boiling point of 150° C. or higher; and (c) from 10 to 1,000 parts by weight of a heat-conductive filler. Also disclosed is an adhesive sheet comprising a substrate and, formed on one or each side thereof, a layer of the adhesive. The pressure-sensitive adhesive can exhibit tight adhesion during use and easy peeling after use.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: March 27, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Hitoshi Takahira, Masahiro Oura, Kazuyuki Kitakura, Takao Yoshikawa, Shigeki Muta
  • Patent number: 6194063
    Abstract: The present invention provides a heat-conductive and pressure-sensitive adhesive sheet comprising an electrical insulating plastic film having formed on one or both of the surfaces thereof (1) at least one thin layer composed of an inorganic material selected from the group consisting of ceramics, metals and metal oxides other than ceramics, and (2) a pressure-sensitive adhesive composition layer formed on the thin layer. The heat-conductive and pressure-sensitive adhesive sheet is excellent in heat-conductivity and pressure-sensitivity, results in no trouble such as complicated procedures in the production process or worsened working environment, exhibits good adhesion between the base material and the pressure-sensitive adhesive composition layer, scarcely undergoes anchoring fracture between the base material even after allowing to stand at high temperatures for a long time, and has good heat resistance.
    Type: Grant
    Filed: January 5, 1999
    Date of Patent: February 27, 2001
    Assignee: Nitto Denko Corporation
    Inventors: Masahiro Oura, Kazuyuki Kitakura, Takao Yoshikawa
  • Patent number: 6086994
    Abstract: Heat-conductive and pressure-sensitive adhesive sheets which are excellent in heat resistance, scarcely undergo anchoring fracture between the base material and the adhesive layer and, therefore, are usable in fixing electronic parts to heat-radiating members or fixing members in various fields including constructive materials, vehicles, aircrafts and ships. the heat-conductive and pressure-sensitive adhesive sheets are in the form of sheets, tapes, etc. wherein a layer of a heat-conductive and pressure-sensitive adhesive composition, which contains an alkyl (meth)acrylate polymer having hydrophilic groups, is formed on the high frequency sputter-etched surface(s) of a plastic film containing 2 to 50% by volume of a heat-conductive, electrical insulating filler.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: July 11, 2000
    Assignee: Nitto Denko Corporation
    Inventors: Masahiro Oura, Kazuyuki Kitakura, Shigeki Muta, Takao Yoshikawa