Patents by Inventor Atsuhiro Nakahara

Atsuhiro Nakahara 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: 10526430
    Abstract: A methacrylic resin composition comprises not less than 90% by mass and not more than 100% by mass of a methacrylic resin [A] having: the total content of a structural unit derived from methyl methacrylate of not less than 90% by mass; a molecular weight MA of not less than 30000 and not more than 100000 in terms of polystyrene corresponding to the retention time indicating the value of the maximum strength in a chromatogram obtained by gel permeation chromatography; the area SgA of a region enclosed by an approximate curve obtained by fitting the data of a range indicating the strength of not less than 70% relative to the value of the maximum strength to a Gaussian function by the method of nonlinear least squares and the base line of the chromatogram of 45 to 80% of the area SA enclosed by the chromatogram and its base line; and the ratio MwgA/MngA of a weight average molecular weight MwgA to a number average molecular weight MngA of not less than 1.01 and not more than 1.
    Type: Grant
    Filed: June 30, 2015
    Date of Patent: January 7, 2020
    Assignee: KURARAY Co., Ltd.
    Inventors: Atsuhiro Nakahara, Toru Abe, Toru Takahashi, Hiroshi Ozawa
  • Patent number: 10407524
    Abstract: A copolymer comprising a structural unit (I) derived from a phosphonate monomer (1) such as diethyl methacryloyloxymethyl phosphonate and diethyl 2-methacryloyloxyethyl phosphonate, a structural unit (II) derived from a radical polymerizable monomer (2) such as methacrylic acid, acrylic acid, 8-tricyclo[5.2.1.02,6]decanyl methacrylate, and t-butyl methacrylate, and a structural unit (III) derived from methyl methacrylate, the content of phosphorus atoms derived from the phosphonate monomer (1) being not less than 1.0% by mass and less than 2.0% by mass relative to the mass of the copolymer, and a formed article comprising the copolymer.
    Type: Grant
    Filed: August 12, 2015
    Date of Patent: September 10, 2019
    Assignee: KURARAY Co., Ltd.
    Inventors: Toru Abe, Atsuhiro Nakahara, Hiroshi Ozawa
  • Patent number: 10287380
    Abstract: Provided are a break-resistant copolymer having high transparency and heat resistance and also having a high tensile strain at break, and a molded article. A copolymer contains 80% by mass to 98% by mass of structural units derived from a methacrylic ester monomer and 2% to 10% by mass of ester structural units derived from a cyclic ketene acetal monomer. The copolymer has a weight average molecular weight of 80,000 or more and a molecular weight distribution of 1.75 to 3.80.
    Type: Grant
    Filed: January 7, 2015
    Date of Patent: May 14, 2019
    Assignee: KURARAY CO., LTD.
    Inventors: Atsuhiro Nakahara, Hiroshi Ozawa, Takashi Fukumoto, Nobutaka Hiraoka
  • Patent number: 10196510
    Abstract: A methacrylic resin [1] having a triad syndiotacticity (rr) of not less than 65% and a methacrylic resin [2] having a triad syndiotacticity (rr) of 45 to 58% are melt kneaded in a mass ratio of the methacrylic resin [1]/the methacrylic resin [2] of 40/60 to 70/30, and further melt kneaded preferably with a polycarbonate resin in a ratio of 1 to 10 parts by mass of the polycarbonate resin to the total 100 parts by mass of the methacrylic resin [1] and the methacrylic resin [2] to obtain a methacrylic resin composition.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: February 5, 2019
    Assignee: KURARAY Co., Ltd.
    Inventors: Toru Takahashi, Atsuhiro Nakahara, Hiroshi Ozawa, Toru Abe, Yusaku Nomoto
  • Publication number: 20190016839
    Abstract: (Meth)acrylate polymers are provided which have a narrow molecular weight distribution on a higher molecular weight side and can impart high shear viscosity stability to lubricating oils. A (meth)acrylate polymer (A) includes specific structural units and is such that in a differential molecular weight distribution curve obtained by gel permeation chromatography (GPC) measurement which shows the polystyrene-equivalent molecular weight of the (meth)acrylate polymer (A) normalized so that the intensity of the peak-top polystyrene-equivalent molecular weight M (t) is 1, the value a represented by a=Log Mh (t1/2)?Log M (t) is not more than 0.12 wherein Mh (t1/2) is the polystyrene-equivalent molecular weight at a point on a higher molecular weight side where the intensity is 0.5.
    Type: Application
    Filed: January 12, 2017
    Publication date: January 17, 2019
    Applicant: KURARAY CO., LTD.
    Inventors: Fumihiko OKABE, Toru TAKAHASHI, Atsuhiro NAKAHARA
  • Patent number: 9964669
    Abstract: A film obtained by molding a methacrylic resin composition, the methacrylic resin composition comprises: a methacrylic resin having a triad syndiotacticity (rr) of not less than 50% and a weight average molecular weight of 80000 to 200000 and comprising not less than 92% by mass of a structural unit derived from methyl methacrylate, and a polycarbonate resin having a melt volume-flow rate of 130 to 250 cm3/20 min at 300° C. and 1.2 Kg, in which a mass ratio of the methacrylic resin to the polycarbonate resin is 91/9 to 99/1, and the total content of the methacrylic resin and the polycarbonate resin is 80 to 100% by mass. The film is layered to at least one surface of a polarizer to give a polarizing plate.
    Type: Grant
    Filed: January 23, 2015
    Date of Patent: May 8, 2018
    Assignee: KURARAY Co., Ltd.
    Inventors: Atsuhiro Nakahara, Toru Abe, Yusaku Nomoto, Wataru Tsuji, Yuuki Takasuka, Takao Hoshiba
  • Patent number: 9856342
    Abstract: A copolymer comprising a structural unit (I) derived from a phosphonate monomer (1) such as diethyl methacryloyloxymethyl phosphonate, diethyl 2-methacryloyloxyethyl phosphonate and the like, and a structural unit (II) derived from a radical polymerizable monomer (2) such as methacrylic acid, acrylic acid, 8-tricyclo[5.2.1.02,6]decanyl methacrylate, t-butyl methacrylate and the like, wherein the content of phosphorus atoms from the phosphonate monomer (1) is 2.0 to 6.0% by mass relative to the mass of the copolymer. A formed article comprising the copolymer.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: January 2, 2018
    Assignee: KURARAY Co., Ltd.
    Inventors: Toru Abe, Atsuhiro Nakahara, Hiroyuki Konishi, Hiroshi Ozawa
  • Publication number: 20170313834
    Abstract: A methacrylate resin composition containing a methacrylate resin and a phenoxy resin and a film consisting of the same, each having high transparency, small phase differences in a thickness direction, low heat shrinkage rate, high strength and good adhesion properties are provided. The methacrylate resin composition contains a methacrylate resin with a triad syndiotacticity (rr) of equal to or more than 58% and a phenoxy resin, and the content of the phenoxy resin per 100 parts by mass of the methacrylate resin is in a range of 0.1 to 8 parts by mass, and the total content of the methacrylate resin and phenoxy resin is 80 mass % or more.
    Type: Application
    Filed: November 11, 2015
    Publication date: November 2, 2017
    Applicant: KURARAY CO., LTD.
    Inventors: Nobutaka HIRAOKA, Toru ABE, Atsuhiro NAKAHARA, Yuuki TAKASUKA, Masayasu OGUSHI
  • Publication number: 20170226249
    Abstract: A copolymer comprising a structural unit (I) derived from a phosphonate monomer (1) such as diethyl methacryloyloxymethyl phosphonate and diethyl 2-methacryloyloxyethyl phosphonate, a structural unit (II) derived from a radical polymerizable monomer (2) such as methacrylic acid, acrylic acid, 8-tricyclo[5.2.1.02,6]decanyl methacrylate, and t-butyl methacrylate, and a structural unit (III) derived from methyl methacrylate, the content of phosphorus atoms derived from the phosphonate monomer (1) being not less than 1.0% by mass and less than 2.0% by mass relative to the mass of the copolymer, and a formed article comprising the copolymer.
    Type: Application
    Filed: August 12, 2015
    Publication date: August 10, 2017
    Applicant: KURARAY Co., Ltd.
    Inventors: Toru ABE, Atsuhiro NAKAHARA, Hiroshi OZAWA
  • Publication number: 20170183428
    Abstract: A methacrylic resin composition comprises not less than 90% by mass and not more than 100% by mass of a methacrylic resin [A] having: the total content of a structural unit derived from methyl methacrylate of not less than 90% by mass; a molecular weight MA of not less than 30000 and not more than 100000 in terms of polystyrene corresponding to the retention time indicating the value of the maximum strength in a chromatogram obtained by gel permeation chromatography; the area SgA of a region enclosed by an approximate curve obtained by fitting the data of a range indicating the strength of not less than 70% relative to the value of the maximum strength to a Gaussian function by the method of nonlinear least squares and the base line of the chromatogram of 45 to 80% of the area SA enclosed by the chromatogram and its base line; and the ratio MwgA/MngA of a weight average molecular weight MwgA to a number average molecular weight MngA of not less than 1.01 and not more than 1.
    Type: Application
    Filed: June 30, 2015
    Publication date: June 29, 2017
    Applicant: KURARAY Co., Ltd.
    Inventors: Atsuhiro NAKAHARA, Toru ABE, Toru TAKAHASHI, Hiroshi OZAWA
  • Publication number: 20170183463
    Abstract: A methacrylic resin composition that has high transparency and a small phase difference in the thickness direction, and is easily stretched is provided. A methacrylic resin composition according to the present invention includes a methacrylic resin and a polycarbonate resin, in which the polycarbonate resin has a viscosity-average molecular weight larger than 15,000 and smaller than 32,000, a content of the polycarbonate resin based on 100 pts.mass of the methacrylic resin is no less than 1 pts.mass and no greater than 4 pts.mass, and a total amount of the methacrylic resin and the polycarbonate resin based on the methacrylic resin composition is 80 to 100 mass %.
    Type: Application
    Filed: April 16, 2015
    Publication date: June 29, 2017
    Applicant: KURARAY CO., LTD.
    Inventors: Atsuhiro NAKAHARA, Toru ABE, Yusaku NOMOTO
  • Publication number: 20170174802
    Abstract: A copolymer comprising structural units derived from a monomer represented by formula (1) and structural units derived from another monomer (A). (In formula (1), ring Z1 represents a C3-10 ring structure optionally having an oxygen atom at any position formed together with two carbon atoms on ?-butyrolactone. R1 represents a hydrogen atom or C1-10 alkyl group.
    Type: Application
    Filed: February 3, 2015
    Publication date: June 22, 2017
    Applicant: KURARAY CO., LTD.
    Inventors: Atsuhiro NAKAHARA, Takashi FUKUMOTO, Hiroyuki KONISHI
  • Patent number: 9605121
    Abstract: A film is obtained by forming a methacrylic resin composition comprising 100 parts by mass of a methacrylic resin (A) and preferably 1 to 10 parts by mass of a polycarbonate resin, the methacrylic resin (A) having a triad syndiotacticity (rr) of not less than 58%, a weight average molecular weight of 50000 to 150000, a content of fraction having a molecular weight of not less than 200000 of 0.1 to 10% by mass and a content of fraction having a molecular weight of less than 15000 of 0.2 to 5% by mass. A polarizer protective film comprising the above film is obtained.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: March 28, 2017
    Assignee: KURARAY Co., Ltd.
    Inventors: Toru Takahashi, Atsuhiro Nakahara, Hiroshi Ozawa, Toru Abe, Yusaku Nomoto
  • Publication number: 20170010390
    Abstract: A film obtained by molding a methacrylic resin composition, the methacrylic resin composition comprises: a methacrylic resin having a triad syndiotacticity (rr) of not less than 50% and a weight average molecular weight of 80000 to 200000 and comprising not less than 92% by mass of a structural unit derived from methyl methacrylate, and a polycarbonate resin having an MVR of 130 to 250 cm3/20 min at 300° C. and 1.2 Kg, in which a mass ratio of the methacrylic resin to the polycarbonate resin is 91/9 to 99/1, and the total content of the methacrylic resin and the polycarbonate resin is 80 to 100% by mass. The film is layered to at least one surface of a polarizer to give a polarizing plate.
    Type: Application
    Filed: January 23, 2015
    Publication date: January 12, 2017
    Applicant: KURARAY CO.,LTD.
    Inventors: Atsuhiro NAKAHARA, Toru ABE, Yusaku NOMOTO, Wataru TSUJI, Yuuki TAKASUKA, Takao HOSHIBA
  • Publication number: 20160326288
    Abstract: Provided are a break-resistant copolymer having high transparency and heat resistance and also having a high tensile strain at break, and a molded article. A copolymer contains 80% by mass to 98% by mass of structural units derived from a methacrylic ester monomer and 2% to 10% by mass of ester structural units derived from a cyclic ketene acetal monomer. The copolymer has a weight average molecular weight of 80,000 or more and a molecular weight distribution of 1.75 to 3.80.
    Type: Application
    Filed: January 7, 2015
    Publication date: November 10, 2016
    Applicant: KURARAY CO., LTD.
    Inventors: Atsuhiro NAKAHARA, Hiroshi OZAWA, Takashi FUKUMOTO, Nobutaka HIRAOKA
  • Publication number: 20160096937
    Abstract: A film is obtained by forming a methacrylic resin composition comprising 100 parts by mass of a methacrylic resin (A) and preferably 1 to 10 parts by mass of a polycarbonate resin, the methacrylic resin (A) having a triad syndiotacticity (rr) of not less than 58%, a weight average molecular weight of 50000 to 150000, a content of fraction having a molecular weight of not less than 200000 of 0.1 to 10% by mass and a content of fraction having a molecular weight of less than 15000 of 0.2 to 5% by mass. A polarizer protective film comprising the above film is obtained.
    Type: Application
    Filed: May 16, 2014
    Publication date: April 7, 2016
    Applicant: KURARAY CO., LTD.
    Inventors: Toru TAKAHASHI, Atsuhiro NAKAHARA, Hiroshi OZAWA, Toru ABE, Yusaku NOMOTO
  • Publication number: 20160090479
    Abstract: A methacrylic resin [1] having a triad syndiotacticity (rr) of not less than 65% and a methacrylic resin [2] having a triad syndiotacticity (rr) of 45 to 58% are melt kneaded in a mass ratio of the methacrylic resin [1]/the methacrylic resin [2] of 40/60 to 70/30, and further melt kneaded preferably with a polycarbonate resin in a ratio of 1 to 10 parts by mass of the polycarbonate resin to the total 100 parts by mass of the methacrylic resin [1] and the methacrylic resin [2] to obtain a methacrylic resin composition.
    Type: Application
    Filed: May 16, 2014
    Publication date: March 31, 2016
    Applicant: KURARAY CO., LTD.
    Inventors: Toru TAKAHASHI, Atsuhiro NAKAHARA, Hiroshi OZAWA, Toru ABE, Yusaku NOMOTO
  • Publication number: 20160053062
    Abstract: An acrylic resin film is obtained by a method comprising bulk-polymerizing methyl methacrylate and an alkyl acrylate ester to obtain an acrylic thermoplastic resin component comprising more than 99% by mass of a methyl methacrylate unit and not more than 1% by mass of an alkyl acrylate ester unit, extruding, through a T-die, a resin composition comprising 70 to 95% by mass of the acrylic thermoplastic resin component and 5 to 30% by mass of a crosslinked rubber particle component, and forming the resultant into a thickness of 20 to 300 ?m with no bank.
    Type: Application
    Filed: April 11, 2014
    Publication date: February 25, 2016
    Applicant: KURARAY CO., LTD.
    Inventors: Kaori MAEDA, Takuya TSUJIMOTO, Takao HOSHIBA, Atsuhiro NAKAHARA
  • Publication number: 20160002380
    Abstract: A copolymer comprising a structural unit (I) derived from a phosphonate monomer (1) such as diethyl methacryloyloxymethyl phosphonate, diethyl 2-methacryloyloxyethyl phosphonate and the like, and a structural unit (II) derived from a radical polymerizable monomer (2) such as methacrylic acid, acrylic acid, 8-tricyclo[5.2.1.02,6]decanyl methacrylate, t-butyl methacrylate and the like, wherein the content of phosphorus atoms from the phosphonate monomer (1) is 2.0 to 6.0% by mass relative to the mass of the copolymer. A formed article comprising the copolymer.
    Type: Application
    Filed: December 27, 2013
    Publication date: January 7, 2016
    Applicant: KURAKAY CO., LTD.
    Inventors: Toru ABE, Atsuhiro NAKAHARA, Hiroyuki KONISHI, Hiroshi OZAWA
  • Publication number: 20150284520
    Abstract: A methacrylic resin composition, comprising a methacrylic resin which comprises 50-90% by mass of a structural unit derived from methyl methacrylate and 10-50% by mass of a structural unit derived from methacrylic acid alicyclic hydrocarbon ester, wherein the difference between the yellow index (YI4) at an optical path length of 200 mm for an injection molded article obtained at a cylinder temperature of 280° C. and a molding cycle of 4 minutes and the yellow index (YI1) at an optical path length of 200 mm for an injection molded article obtained at a cylinder temperature of 280° C. and a molding cycle of 1 minute is 3 or less, and the melt flow rate at a temperature of 230° C. and under a load of 3.8 kg is 5 g/10 min or more.
    Type: Application
    Filed: November 8, 2013
    Publication date: October 8, 2015
    Applicant: KURARAY CO., LTD.
    Inventors: Hiroshi Ozawa, Takuro Niimura, Atsushi Matsumura, Atsuhiro Nakahara