Patents by Inventor Kouji Akazawa

Kouji Akazawa 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: 8021756
    Abstract: The present invention provides a microlens array produced by molding a resin obtained by reacting a silicon compound with a boron compound or an aluminum compound, in which the silicon compound is represented by the following formula (I): in which R1 and R2 each independently represent an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group, in which a plurality of R1's are the same or different and a plurality of R2's are the same or different; X represents a hydroxy group, an alkoxy group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group; and n is 4 to 250. This microlens array has excellent heat resistance and light resistance even when applied to LEDs having an increased power and to LEDs emitting blue light having a short wavelength.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: September 20, 2011
    Assignee: Nitto Denko Corporation
    Inventors: Ichiro Suehiro, Hiroyuki Katayama, Kouji Akazawa, Hideyuki Usui
  • Patent number: 7976952
    Abstract: To provide a pressure-sensitive adhesive sheet used during processing articles such as semiconductor wafers and laminate sheet used for such a pressure-sensitive adhesive sheet, which does not contaminate or break the semiconductor wafers during the processing and can minimize the curl of the articles due to residual stress of the pressure-sensitive adhesive sheet, a multi-layer sheet includes a composite film containing a urethane polymer and a vinyl-based polymer as effective components and a first film made of a material different from that of the composite film, wherein the urethane polymer is formed from a polyolefin diol and a polyisocyanate. A pressure-sensitive adhesive sheet is obtained by providing a pressure-sensitive adhesive layer on at least one side of the multi-layer sheet.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: July 12, 2011
    Assignee: Nitto Denko Corporation
    Inventors: Yoshinori Yoshida, Kouji Akazawa, Tomohiro Kontani, Kohei Yano
  • Patent number: 7951623
    Abstract: The present invention relates to a process for producing an optical semiconductor device, the process including: disposing a sheet for optical-semiconductor-element encapsulation including a resin sheet A and a plurality of resin layers B discontinuously embedded in the resin sheet A and a plurality of optical semiconductor elements mounted on a substrate in such a way that each of the plurality of optical semiconductor elements faces either one of the plurality of resin layers B; and followed by embedding each of the plurality of optical semiconductor elements in either one of the plurality of resin layers B. According to the process of the invention, optical semiconductor elements can be embedded at once. As a result, an optical semiconductor device which is excellent in LED element protection and durability can be easily obtained. Consequently, the optical semiconductor device obtained can have a prolonged life.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: May 31, 2011
    Assignee: Nitto Denko Corporation
    Inventors: Noriaki Harada, Ryuuichi Kimura, Kouji Akazawa
  • Patent number: 7781794
    Abstract: The present invention provides a resin sheet for encapsulating an optical semiconductor element, the resin sheet containing an encapsulation resin layer, an adhesive resin layer, a metal layer and a protective resin layer, in which the encapsulation resin layer and the metal layer adhered onto the adhesive resin layer are disposed adjacently to each other, the protective resin layer is laminated on the encapsulation resin layer and the metal layer so as to cover both the encapsulation resin layer and the metal layer, and the encapsulation resin layer has a taper shape expanding toward the protective resin layer; and an optical semiconductor device containing an optical semiconductor element encapsulated by using the resin sheet. The optical semiconductor element encapsulation resin sheet of the invention can be suitably used for back lights of liquid crystal screens, traffic signals, large-sized outdoor displays, billboards and the like.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: August 24, 2010
    Assignee: Nitto Denko Corporation
    Inventors: Ichiro Suehiro, Kouji Akazawa, Hideyuki Usui
  • Patent number: 7777356
    Abstract: A modified polyaluminosiloxane obtained by treating a polyaluminosiloxane with a silane coupling agent represented by the formula (I): wherein each of R1, R2 and R3 is independently an alkyl group or an alkoxy group; X is a methacryloxy group, a glycidoxy group, an amino group, a vinyl group or a mercapto group, with proviso that at least two of R1, R2 and R3 are alkoxy groups. The photosemiconductor element encapsulating material of the present invention is suitably used for, for example, photosemiconductor devices mounted with blue or white LED elements (backlights for liquid crystal displays, traffic lights, outdoor big displays, advertisement sign boards, and the like).
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: August 17, 2010
    Assignee: Nitto Denko Corporation
    Inventors: Hiroyuki Katayama, Kouji Akazawa
  • Publication number: 20100053960
    Abstract: The present invention provides a microlens array produced by molding a resin obtained by reacting a silicon compound with a boron compound or an aluminum compound, in which the silicon compound is represented by the following formula (I): in which R1 and R2 each independently represent an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group, in which a plurality of R1's are the same or different and a plurality of R2's are the same or different; X represents a hydroxy group, an alkoxy group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group; and n is 4 to 250. This microlens array has excellent heat resistance and light resistance even when applied to LEDs having an increased power and to LEDs emitting blue light having a short wavelength.
    Type: Application
    Filed: August 25, 2009
    Publication date: March 4, 2010
    Applicant: NITTO DENKO CORPORATION
    Inventors: Ichiro SUEHIRO, Hiroyuki KATAYAMA, Kouji AKAZAWA, Hideyuki USUI
  • Publication number: 20090242928
    Abstract: The present invention provides a resin sheet for encapsulating an optical semiconductor element, the resin sheet containing an encapsulation resin layer, an adhesive resin layer, a metal layer and a protective resin layer, in which the encapsulation resin layer and the metal layer adhered onto the adhesive resin layer are disposed adjacently to each other, the protective resin layer is laminated on the encapsulation resin layer and the metal layer so as to cover both the encapsulation resin layer and the metal layer, and the encapsulation resin layer has a taper shape expanding toward the protective resin layer; and an optical semiconductor device containing an optical semiconductor element encapsulated by using the resin sheet. The optical semiconductor element encapsulation resin sheet of the invention can be suitably used for back lights of liquid crystal screens, traffic signals, large-sized outdoor displays, billboards and the like.
    Type: Application
    Filed: March 24, 2009
    Publication date: October 1, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Ichiro SUEHIRO, Kouji AKAZAWA, Hideyuki USUI
  • Publication number: 20090227757
    Abstract: A modified polyaluminosiloxane obtained by treating a polyaluminosiloxane with a silane coupling agent represented by the formula (I): wherein each of R1, R2 and R3 is independently an alkyl group or an alkoxy group; X is a methacryloxy group, a glycidoxy group, an amino group, a vinyl group or a mercapto group, with proviso that at least two of R1, R2 and R3 are alkoxy groups. The photosemiconductor element encapsulating material of the present invention is suitably used for, for example, photosemiconductor devices mounted with blue or white LED elements (backlights for liquid crystal displays, traffic lights, outdoor big displays, advertisement sign boards, and the like).
    Type: Application
    Filed: February 3, 2009
    Publication date: September 10, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hiroyuki KATAYAMA, Kouji Akazawa
  • Patent number: 7514143
    Abstract: The re-peelable pressure-sensitive adhesive sheet of the invention is a re-peelable pressure-sensitive adhesive sheet, which comprises an adhesive layer formed over a base film, and which further comprises at least one intermediate layer between the base film and the adhesive layer, the intermediate layer having a storage elastic modulus (G?) of 3.0×104 to 1.0×108 Pa at 23° C. and a storage elastic modulus (G?) of 1.0×103 to 8.0×104 Pa at 200° C.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: April 7, 2009
    Assignee: Nitto Denko Corporation
    Inventors: Takeshi Matsumura, Kouji Akazawa, Kazuyuki Kiuchi, Tomokazu Takahashi
  • Publication number: 20090061549
    Abstract: The present invention relates to a process for producing an optical semiconductor device, the process including: disposing a sheet for optical-semiconductor-element encapsulation including a resin sheet A and a plurality of resin layers B discontinuously embedded in the resin sheet A and a plurality of optical semiconductor elements mounted on a substrate in such a way that each of the plurality of optical semiconductor elements faces either one of the plurality of resin layers B; and followed by embedding each of the plurality of optical semiconductor elements in either one of the plurality of resin layers B. According to the process of the invention, optical semiconductor elements can be embedded at once. As a result, an optical semiconductor device which is excellent in LED element protection and durability can be easily obtained. Consequently, the optical semiconductor device obtained can have a prolonged life.
    Type: Application
    Filed: September 2, 2008
    Publication date: March 5, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Noriaki HARADA, Ryuuichi KIMURA, Kouji AKAZAWA
  • Publication number: 20090014750
    Abstract: The present invention relates to a resin for optical semiconductor element encapsulation containing a polyborosiloxane obtained by reacting a silicon compound with a boron compound; and an optical semiconductor device containing the resin and an optical semiconductor element encapsulated with the resin. The resin for optical semiconductor element encapsulation according to the invention exhibits an excellent advantage that it is excellent in all of heat resistance, transparency, and light resistance.
    Type: Application
    Filed: July 11, 2008
    Publication date: January 15, 2009
    Applicant: NITTO DENKO CORPORATION
    Inventors: Hiroyuki KATAYAMA, Kouji AKAZAWA
  • Publication number: 20080193728
    Abstract: Disclosed is a pressure-sensitive adhesive sheet for use in processing a product such a semiconductor wafer. To provide a pressure-sensitive adhesive sheet that provides a minimized number of broken semiconductor wafers during the process of polishing them and that produces a less curl of the wafer due to the residual stress of the pressure-sensitive adhesive sheet, the pressure-sensitive adhesive sheet includes a composite film formed from a composition containing a urethane polymer and a vinyl polymer as effective components, a first film comprising a material different from that of the composite film, and a pressure-sensitive adhesive layer. It is preferable that the pressure-sensitive adhesive sheet has a modulus of 9 N/mm2 or more and 250 N/mm2 or less when an oblong piece of the pressure-sensitive adhesive sheet with a width of 20 mm is bent at a radius of curvature of 3.0 mm.
    Type: Application
    Filed: March 19, 2008
    Publication date: August 14, 2008
    Applicant: NITTO DENKO CORPORATION
    Inventors: Yoshinori YOSHIDA, Yohei Maeno, Kouji Akazawa, Takeshi Matsumura, Tomokazu Takahashi
  • Publication number: 20070071969
    Abstract: To provide a pressure-sensitive adhesive that is used in processing an article such as a semiconductor wafer that causes neither contamination nor breakage of the semiconductor wafer during the processing, the pressure-sensitive adhesive sheet has a base, an intermediate layer, and a pressure-sensitive adhesive layer in order. The intermediate layer includes a composite film that contains an acrylic-based polymer and a vinyl-based polymer as active ingredients. The urethane polymer contains a component having a weight-average molecular weight of 10,000 or less in a differential molecular weight curve in a content of less than 10%.
    Type: Application
    Filed: September 20, 2006
    Publication date: March 29, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Tomohiro Kontani, Kouji Akazawa, Kohei Yano, Yoshinori Yoshida
  • Publication number: 20070059903
    Abstract: To provide a pressure-sensitive adhesive that is used in processing an article such as a semiconductor wafer, the pressure-sensitive adhesive sheet is one that has a base, an intermediate layer and a pressure-sensitive adhesive layer in order, wherein the intermediate layer has an elastic modulus at elongation at 23° C. of 1 MPa or more and 100 MPa or less, the intermediate layer includes an acrylic polymer obtained by polymerization of a (meth) acrylic monomer mixture containing 1% by weight or more and 20% by weight or less of a nitrogen-containing acrylic monomer, the acrylic polymer containing 20% by weight or less of a polymer component having a molecular weight of 100,000 or less, and the base includes at least one film having an elastic modulus at in tension at 23° C. of 0.6 GPa or more.
    Type: Application
    Filed: September 1, 2006
    Publication date: March 15, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kohei Yano, Kouji Akazawa, Yoshinori Yoshida, Tomohiro Kontani
  • Publication number: 20070054469
    Abstract: To provide a pressure-sensitive adhesive sheet, which is used in processing an article such as a semiconductor wafer, the pressure-sensitive adhesive sheet has a base, an intermediate layer and a pressure-sensitive adhesive layer in this order, wherein the intermediate layer has an elastic modulus in tension at 23° C. of 10 MPa or more and 100 Mpa or less, the intermediate layer includes an acrylic-based polymer obtained by polymerization of a mixture containing 70 to 99 parts by weight of a (meth)acrylate monomer and 1 to 30 parts by weight of an unsaturated carboxylic acid based on 100 parts by weight of total monomers, and the base includes at least one film having an elastic modulus in tension at 23° C. of 0.6 GPa or more.
    Type: Application
    Filed: September 1, 2006
    Publication date: March 8, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Kohei Yano, Kouji Akazawa, Yoshinori Yoshida, Tomohiro Kontani
  • Publication number: 20070036930
    Abstract: To provide a pressure-sensitive adhesive sheet for use in processing wafers and the like articles, that produces less cutting sludge of the pressure-sensitive adhesive sheet and that can follow up unevenness of a wafer even when a difference in height of the unevenness is large, the pressure-sensitive adhesive sheet includes a base having on one surface thereof an intermediate layer and a pressure-sensitive adhesive layer in order, wherein the intermediate layer has an initial elastic modulus of 0.5 N/mm2 or less, a loss tangent (tan?) at 20° C. to 70° C. of 0.
    Type: Application
    Filed: August 7, 2006
    Publication date: February 15, 2007
    Applicant: NITTO DENKO CORPORATION
    Inventors: Tomohiro Kontani, Yoshinori Yoshida, Toshio Shintani, Kouji Akazawa
  • Publication number: 20060257651
    Abstract: According to the invention, a pressure-sensitive adhesive sheet for use in dicing of a workpiece is provided which comprises a base film and at least a pressure-sensitive adhesive layer provided on the base film, wherein the pressure-sensitive adhesive layer comprises an acrylic polymer that contains at least 5% by weight of a monomer unit having an alkoxyl group in its side chain. According to the structure, there are provided a pressure-sensitive adhesive sheet for dicing that can produce good pickup performance even after a long time and a method of picking up a product worked with the pressure-sensitive adhesive sheet.
    Type: Application
    Filed: May 15, 2006
    Publication date: November 16, 2006
    Inventors: Toshio Shintani, Tomokazu Takahashi, Syouji Yamamoto, Kazuyuki Kiuchi, Fumiteru Asai, Kouji Akazawa
  • Publication number: 20060188725
    Abstract: To provide a pressure-sensitive adhesive sheet used during processing articles such as semiconductor wafers and laminate sheet used for such a pressure-sensitive adhesive sheet, which does not contaminate or break the semiconductor wafers during the processing and can minimize the curl of the articles due to residual stress of the pressure-sensitive adhesive sheet, a multi-layer sheet includes a composite film containing a urethane polymer and a vinyl-based polymer as effective components and a first film made of a material different from that of the composite film, wherein the urethane polymer is formed from a polyolefin diol and a polyisocyanate. A pressure-sensitive adhesive sheet is obtained by providing a pressure-sensitive adhesive layer on at least one side of the multi-layer sheet.
    Type: Application
    Filed: February 21, 2006
    Publication date: August 24, 2006
    Applicant: NITTO DENKO CORPORATION
    Inventors: Yoshinori Yoshida, Kouji Akazawa, Tomohiro Kontani, Kohei Yano
  • Publication number: 20050153129
    Abstract: Disclosed is a pressure-sensitive adhesive sheet for use in processing a product such a semiconductor wafer. To provide a pressure-sensitive adhesive sheet that provides a minimized number of broken semiconductor wafers during the process of polishing them and that produces a less curl of the wafer due to the residual stress of the pressure-sensitive adhesive sheet, the pressure-sensitive adhesive sheet includes a composite film formed from a composition containing a urethane polymer and a vinyl polymer as effective components, a first film comprising a material different from that of the composite film, and a pressure-sensitive adhesive layer. It is preferable that the pressure-sensitive adhesive sheet has a modulus of 9 N/mm2 or more and 250 N/mm2 or less when an oblong piece of the pressure-sensitive adhesive sheet with a width of 20 mm is bent at a radius of curvature of 3.0 mm.
    Type: Application
    Filed: January 21, 2005
    Publication date: July 14, 2005
    Inventors: Yoshinori Yoshida, Yohei Maeno, Kouji Akazawa, Takeshi Matsumura, Tomokazu Takahashi
  • Publication number: 20050031861
    Abstract: The re-peelable pressure-sensitive adhesive sheet of the invention is a re-peelable pressure-sensitive adhesive sheet, which comprises an adhesive agent layer formed over a base film, and which further comprises at least one intermediate layer between the base film and the adhesive agent layer, the intermediate layer having a storage elastic modulus (G?) of 3.0×104 to 1.0×108 Pa at 23° C. and a storage elastic modulus (G?) of 1.0×103 to 8.0×104 Pa at 200° C. Even when this re-peelable pressure-sensitive adhesive sheet and a semiconductor wafer are adhered to each other and they are placed, as they are, in a heating environment, the wafer can be prevented from being warped.
    Type: Application
    Filed: August 5, 2004
    Publication date: February 10, 2005
    Inventors: Takeshi Matsumura, Kouji Akazawa, Kazuyuki Kiuchi, Tomokazu Takahashi