Patents by Inventor Kazufumi Kai

Kazufumi Kai 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: 20170341342
    Abstract: The present invention provides a light control panel, including a plurality of band-shaped planar light-reflecting portions in each of which layers of a cured product of an allyl ester resin composition, which cured product is excellent in optical characteristics, surface hardness and strength, and metal film layers are alternately laminated in a plane direction (direction vertical to a thickness). The allyl ester resin composition preferably contains an allyl ester oligomer having a group represented by the formula (2) as a terminal group, and having a structure represented by the formula (3) as a structural unit (the symbols in formulae (2) and (3) have the same meanings as those described in the description).
    Type: Application
    Filed: November 20, 2015
    Publication date: November 30, 2017
    Applicant: SHOWA DENKO K.K.
    Inventors: Kazufumi KAI, Yasuyuki OYAMA
  • Patent number: 8518524
    Abstract: The invention provides a transparent composite material comprising a cured product of a three-dimensionally crosslinkable resin composition containing tabular inorganic substance having a number-average particle size of 10 to 300 nm and an aspect ratio of 10 to 300 dispersed therein, which material has a small coefficient of thermal expansion against surrounding temperature changes and can be suitably applicable as substrate for display devices, to thereby overcome disadvantages in substrate for display devices using conventional materials that differences in thermal shrinkage between a substrate and an transparent electrode cause cracks in the transparent electrode, resulting in increasing resistance and causing disconnection, and further can provide a display device with high durability.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: August 27, 2013
    Assignee: Showa Denko K.K.
    Inventors: Yasushi Kadowaki, Kazufumi Kai, Ryoji Toita
  • Patent number: 8163860
    Abstract: The invention relates to a norbornene copolymer having excellent properties such as transparency, heat resistance, low water absorption and electric insulating property, which copolymer comprises a monomer unit represented by formula (1) and formula (2) and having a number average molecular weight (Mn) of 300,000 to 2,000,000. (In the formulae, R1 represents an alkyl group having 1 to 10 carbon atoms; and R2, R3 and R4 independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: April 24, 2012
    Assignees: Showa Denko K.K., Riken
    Inventors: Shojiro Kaita, Nobuyuki Kibino, Kazufumi Kai
  • Patent number: 8119039
    Abstract: A transparent conductive substrate using allyl ester heat-curable resin, including a compound having a group represented by formula (2) as terminus and a group represented by formula (3) as repeating unit, where R3, A2, and A3 in the formulae have the same meanings as defined in the specification.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: February 21, 2012
    Assignee: Showa Denko K.K.
    Inventors: Yasushi Kadowaki, Kazufumi Kai
  • Publication number: 20110282014
    Abstract: The invention relates to a norbornene copolymer having excellent properties such as transparency, heat resistance, low water absorption and electric insulating property, which copolymer comprises a monomer unit represented by formula (1) and formula (2) and having a number average molecular weight (Mn) of 300,000 to 2,000,000. (In the formulae, R1 represents an alkyl group having 1 to 10 carbon atoms; and R2, R3 and R4 independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.
    Type: Application
    Filed: January 29, 2010
    Publication date: November 17, 2011
    Applicants: RIKEN, SHOWA DENKO K.K.
    Inventors: Shojiro Kaita, Nobuyuki Kibino, Kazufumi Kai
  • Publication number: 20110124815
    Abstract: The invention relates to polyurethane having s excellent electric insulating property and thermal stability, obtained by a polyaddition reaction between a polyol copolymer which is a copolymer comprising as monomer units the structures represented by formulae (1) and (2) and a polyisocyanate compound: wherein R represents aliphatic hydrocarbon group having 2 to 20 carbon atoms, which may be branched and may contain a cyclic structure; and a production method thereof.
    Type: Application
    Filed: August 4, 2009
    Publication date: May 26, 2011
    Applicant: SHOWA DENKO K.K.
    Inventors: Nobuyuki Kibino, Kazufumi Kai
  • Patent number: 7939612
    Abstract: A radically polymerizable compound having a group represented by formula (1) (In the formula, R1 to R3 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X represents an alkylene group having 1 to 4 carbon atoms.) and a radically polymerizable double bond and a composition for an optical material comprising the same have a high refractive index and excellent transparency and are hard to be oxidized in thermal curing and useful as an optical material with little tinting.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: May 10, 2011
    Assignee: Showa Denko K.K.
    Inventors: Keisuke Ohta, Yasuyuki Oyama, Kazufumi Kai
  • Publication number: 20100286354
    Abstract: The invention relates to an allyl alcohol copolymer comprising structures represented by formula (1) and (2) as monomer units. (In the formula, R represents an aliphatic hydrocarbon group having 2 to 20 carbon atoms, which may be branched or include a cyclic structure). The copolymer of the invention is excellent in compatibility with various resins, adhesiveness, electric insulation, low water absorption, thermal stability and surface active effect.
    Type: Application
    Filed: December 22, 2008
    Publication date: November 11, 2010
    Applicant: SHOWA DENKO K.K.
    Inventors: Nobuyuki Kibino, Yukiharu Hetsugi, Kazufumi Kai
  • Publication number: 20090324922
    Abstract: The invention provides a transparent composite material comprising a cured product of a three-dimensionally crosslinkable resin composition containing tabular inorganic substance having a number-average particle size of 10 to 300 nm and an aspect ratio of 10 to 300 dispersed therein, which material has a small coefficient of thermal expansion against surrounding temperature changes and can be suitably applicable as substrate for display devices, to thereby overcome disadvantages in substrate for display devices using conventional materials that differences in thermal shrinkage between a substrate and an transparent electrode cause cracks in the transparent electrode, resulting in increasing resistance and causing disconnection, and further can provide a display device with high durability.
    Type: Application
    Filed: July 20, 2007
    Publication date: December 31, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Yasushi Kadowaki, Kazufumi Kai, Ryoji Toita
  • Publication number: 20090270574
    Abstract: A radically polymerizable compound having a group represented by formula (1) (In the formula, R1 to R3 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X represents an alkylene group having 1 to 4 carbon atoms.) and a radically polymerizable double bond and a composition for an optical material comprising the same have a high refractive index and excellent transparency and are hard to be oxidized in thermal curing and useful as an optical material with little tinting.
    Type: Application
    Filed: January 26, 2007
    Publication date: October 29, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Keisuke Ohta, Yasuyuki Oyama, Kazufumi Kai
  • Patent number: 7569327
    Abstract: This invention relates to a novel polymer compound, and a process for preparing the same and a radical polymerizable, curable composition using the same. The polymer of the invention has in the side chain thereof a structure represented by the formula (1): wherein R1 each independently represents at least one or more organic residue selected from the group consisting of an alkylene group, a branched alkylene group, a cycloalkylene group, an aralkylene group and an arylene group, R2 each independently represents at least one or more organic residue selected from the group consisting of an alkylene group, a branched alkylene group, an alkenylene group, a branched alkenylene group, a cycloalkylene group, a cycloalkenylene group and an arylene group, and n represents an integer of 0 to 20.
    Type: Grant
    Filed: May 25, 2004
    Date of Patent: August 4, 2009
    Assignee: Showda Denko K.K.
    Inventors: Hirotoshi Kamata, Keisuke Ohta, Kazufumi Kai
  • Publication number: 20090192279
    Abstract: The invention relates to a radically polymerizable sulfur-containing compound having a group represented by formula (1) and at least one selected from among groups represented by formulae (2) to (4), a radically polymerizable sulfur-containing polymer obtained by subjecting the compound to cationic ring-opening (co)polymerization, production process thereof, a composition containing the sulfur-containing compound and/or the sulfur-containing polymer, and a cured product obtained from the composition. (R1 to R6 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) The cured product obtained from the radically polymerizable sulfur-containing compound and the radically polymerizable sulfur-containing polymer having a high refractive index is useful as an optical material, especially for lens material.
    Type: Application
    Filed: February 5, 2009
    Publication date: July 30, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Keisuke OHTA, Tsuneo TAJIMA, Kazufumi KAI, Yasuyuki OYAMA
  • Publication number: 20090166589
    Abstract: The invention provides a transparent conductive substrate using allyl ester heat-curable resin, comprising a compound having a group represented by formula (2) as terminus and a group represented by formula (3) as repeating unit, (In the formulae, R3 A2 and A3 have the same meanings as defined in the Description). The transparent conductive substrate is useful as a plastic substrate for display device, characterized by excellent heat resistance and chemical resistance, a low average linear expansion coefficient and high transparency, where warpage, deformation, crack of wiring are hard to occur in a process of thin film device formation.
    Type: Application
    Filed: April 5, 2007
    Publication date: July 2, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Yasushi Kadowaki, Kazufumi Kai
  • Patent number: 7518001
    Abstract: The invention relates to a radically polymerizable sulfur-containing compound having a group represented by formula (1) and at least one selected from among groups represented by formulae (2) to (4), a radically polymerizable sulfur-containing polymer obtained by subjecting the compound to cationic ring-opening (co)polymerization, production process thereof, a composition containing the sulfur-containing compound and/or the sulfur-containing polymer, and a cured product obtained from the composition . . . (1)(2)(3)(4) . . . (R1 to R6 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) The cured product obtained from the radically polymerizable sulfur-containing compound and the radically polymerizable sulfur-containing polymer having a high refractive index is useful as an optical material, especially for lens material.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: April 14, 2009
    Assignee: Showa Denko K.K.
    Inventors: Keisuke Ohta, Tsuneo Tajima, Kazufumi Kai, Yasuyuki Oyama
  • Publication number: 20070208149
    Abstract: The invention relates to a radically polymerizable sulfur-containing compound having a group represented by formula (1) and at least one selected from among groups represented by formulae (2) to (4), a radically polymerizable sulfur-containing polymer obtained by subjecting the compound to cationic ring-opening (co)polymerization, production process thereof, a composition containing the sulfur-containing compound and/or the sulfur-containing polymer, and a cured product obtained from the composition . . . (1)(2)(3)(4) . . . (R1 to R6 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) The cured product obtained from the radically polymerizable sulfur-containing compound and the radically polymerizable sulfur-containing polymer having a high refractive index is useful as an optical material, especially for lens material.
    Type: Application
    Filed: September 20, 2005
    Publication date: September 6, 2007
    Applicant: SHOWA DENKO K.K.
    Inventors: Keisuke Ohta, Tsuneo Tajima, Kazufumi Kai, Yasuyuki Oyama
  • Publication number: 20070021571
    Abstract: This invention relates to a novel polymer compound, and a process for preparing the same and a radical polymerizable, curable composition using the same. The polymer of the invention has in the side chain thereof a structure represented by the formula (1): wherein R1 each independently represents at least one or more organic residue selected from the group consisting of an alkylene group, a branched alkylene group, a cycloalkylene group, an aralkylene group and an arylene group, R2 each independently represents at least one or more organic residue selected from the group consisting of an alkylene group, a branched alkylene group, an alkenylene group, a branched alkenylene group, a cycloalkylene group, a cycloalkenylene group and an arylene group, and n represents an integer of 0 to 20.
    Type: Application
    Filed: May 25, 2004
    Publication date: January 25, 2007
    Inventors: Hirotoshi Kamata, Keisuke Ohta, Kazufumi Kai
  • Patent number: 7049350
    Abstract: A polymerizable compound represented by formula (1): wherein each R1 independently represents at least one organic residue selected from the group consisting of alkylene groups, branched alkylene groups, cycloalkylene groups and arylene groups, R2 represents an organic residue derived from an alcohol compound, a phenol compound or a carboxylic acid compound, n represents an integer of 0 to 20, a production process of the polymerizable composition, a composition using the polymerizable compound, a cured product obtained by curing the composition and a production process of the cured product. The polymerizable compound exhibits a good adhesive property to a substrate such as glass and is imparted with radical polymerizability to enable heat curing and/or active energy ray curing.
    Type: Grant
    Filed: July 25, 2002
    Date of Patent: May 23, 2006
    Assignee: Showa Denko K.K.
    Inventors: Yoshihiro Honda, Keisuke Ohta, Kazuhiko Ooga, Kazufumi Kai, Hiroshi Uchida
  • Patent number: 7038076
    Abstract: This invention is to provide a polymerizable composition having excellent curability and surface hardness, and a cured product thereof. A novel fumarate derivative having two or more fumarate groups within one molecule and ensuring copolymerizability with the terminal alkenyloxy group, a method for producing the derivative, a polymerizable composition containing the derivative, and a cured product thereof are provided.
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: May 2, 2006
    Assignee: Showa Denko K.K.
    Inventors: Kazufumi Kai, Keisuke Ohta, Yasushi Kadowaki, Hiroshi Uchida
  • Patent number: 6846900
    Abstract: A compound favored with low viscosity, capable of providing a cured product having high refractive index, and suitable for application to optical materials, including plastic lens material, radical polymerizable flame retardant and the like, as well as a process for producing the compound, a plastic lens composition using the compound, a plastic lens obtained by curing the composition and a process for producing the plastic lens. A novel aromatic ring-containing polyvalent (meth)allyl ester derived from a polyvalent carboxylic acid of trivalent or greater valent is employed.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: January 25, 2005
    Assignee: Showa Denko K.K.
    Inventors: Kazuhiko Ooga, Tsuneo Tajima, Kazufumi Kai, Hiroshi Uchida
  • Publication number: 20040235980
    Abstract: A polymerizable compound represented by formula (1): wherein each R1 independently represents at least one organic residue selected from the group consisting of alkylene groups, branched alkylene groups, cycloalkylene groups and arylene groups, R2 represents an organic residue derived from an alcohol compound, a phenol compound or a carboxylic acid compound, n represents an integer of 0 to 20, a production process of the polymerizable composition, a composition using the polymerizable compound, a cured product obtained by curing the composition and a production process of the cured product. The polymerizable compound exhibits a good adhesive property to a substrate such as glass and is imparted with radical polymerizability to enable heat curing and/or active energy ray curing.
    Type: Application
    Filed: January 27, 2004
    Publication date: November 25, 2004
    Inventors: Yoshihiro Honda, Keisuke Ohta, Kazuhiko Ooga, Kazufumi Kai, Hiroshi Uchida