Patents Assigned to Kureha Kagaku Kogyo
  • Patent number: 6916939
    Abstract: The present invention provides a process for production of a cyclic ester by depolymerization of an aliphatic polyester. In the process, a mixture containing the aliphatic polyester and a specific polyalkylene glycol ether, which has a boiling point of 230-450° C. and a molecular weight of 150-450, is heated under normal or reduced pressure to a temperature at which depolymerization of the aliphatic polyester takes place. Then, a substantially homogeneous solution phase, consisting of the melt phase of the aliphatic polyester and the liquid phase of the polyalkylene glycol ether, is formed. Heating of the solution phase is continued to form the cyclic ester by depolymerization and distil out the cyclic ester together with the polyalkylene glycol ether, and then the cyclic ester is recovered from the distillate. The present invention also provides a process for purification of a crude cyclic ester by use of the specific polyalkylene glycol ether described above.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: July 12, 2005
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Kazuyuki Yamane, Yukichika Kawakami, Hajime Hoshi, Kazuhiko Sunagawa
  • Patent number: 6891048
    Abstract: The invention provides a process for producing glycolide by depolymerization by heating of a glycolic acid oligomer in the presence or absence of a solvent, which process ensures stable depolymerization. The depolymerization reaction is carried out while the content of alkaline metal ions in a glycolic acid oligomer-containing depolymerization reaction system is controlled to 0.001% by mass or lower; a sulfate or an organic acid salt, each in the form of di- or poly-valent cations, or a mixture thereof is allowed to be present as a stabilizer in the depolymerization reaction system; or the content of alkaline metal ions in the depolymerization reaction system is controlled to 0.001% by mass or lower, and a sulfate or an organic acid salt, each in the form of di- or poly-valent cations, or a mixture thereof is allowed to be present as a stabilizer in the depolymerization reaction system.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: May 10, 2005
    Assignee: Kureha Kagaku Kogyo KK
    Inventors: Kazuyuki Yamane, Yukichika Kawakami
  • Patent number: 6846436
    Abstract: A semiconductive polyvinylidene fluoride resin composition comprising 100 parts by weight of a polyvinylidene fluoride resin, 0.03 to 10 parts by weight of at least one tetraalkylammonium salt selected from the group consisting of tetraalkylammonium sulfates and tetraalkylammonium sulfites, and 1 to 20 parts by weight of conductive carbon black. A formed or molded product composed of the semiconductive polyvinylidene fluoride resin composition.
    Type: Grant
    Filed: May 11, 2000
    Date of Patent: January 25, 2005
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Hideki Kitamura, Satoru Matsunaga, Mitsuru Ito, Nobuhiro Moriyama
  • Patent number: 6824927
    Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: November 30, 2004
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Patent number: 6762229
    Abstract: A poly(arylene sulfide) resin composition comprising a poly(arylene sulfide) and, as a modifier, an organic amide compound compounded in a proportion of 0.2 to 10 parts by weight per 100 parts by weight of the poly(arylene sulfide).
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: July 13, 2004
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Naomitsu Nishihata, Masahito Tada, Hiroyuki Sato, Kiyomi Ohuchi
  • Patent number: 6699549
    Abstract: A polyester-surfaced heat-shrinkable multilayer film exhibiting good printability and adaptability to various automatic packaging processes is provided, including an outer surface layer (a) comprising a polyester resin, an intermediate layer (b) comprising a polyamide resin and an inner surface layer (c) comprising a sealable resin. The film exhibits a heat-shrinkable stress at 50° C. of at most 3 MPa both in longitudinal direction and in transverse direction, and a hot water shrinkability at 90° C. of at least 20%.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: March 2, 2004
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Takahisa Ueyama, Tadayoshi Itoh, Eiichi Hayashi, Hajime Tsukamoto
  • Patent number: 6693204
    Abstract: A method of refining a crystal of a crude cyclic ester comprises the steps of supplying the crude cyclic ester to a vertically extending cylindrical refiner (1) from an inlet (3) provided at a lower part of the refiner (1), agitating the crude cyclic ester by an agitator provided in the refiner (1) to make the crude cyclic ester flow upwardly, refining the crystals of the crude cyclic ester by counterflow-contact between the upflowing crude cyclic ester and a downflowing melted liquid containing a refined crystal component, and taking out refined crystals of the crude cyclic ester from an outlet (4) provided at an upper part of the refiner (1).
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: February 17, 2004
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Tetsuo Ejiri, Kazuyuki Yamane, Kentaro Otawara
  • Patent number: 6686048
    Abstract: A composite carbonaceous heat insulator which comprises a carbonaceous heat-insulating member having a bulk density of 0.1 to 0.4 g/cm3, a carbonaceous protecting layer having a bulk density of 0.3 to 2.0 g/cm3 and comprising a carbon fiber structure and a thermally decomposed carbon penetrated into the structure, and a thermally decomposed carbon coating layer having a bulk density higher than that of the carbonaceous protecting layer, wherein the above carbonaceous protecting layer is jointed to at least a part of the carbonaceous heat-insulating member to form a jointed body, and the thermally decomposed carbon coating layer is formed at least on the face of carbonaceous heat-insulating member in the surface of the jointed body; and a method for manufacturing the insulator. The heat insulator is reduced with respect to the depletion, deterioration and pulverization during the use thereof, while maintaining excellent insulating characteristics.
    Type: Grant
    Filed: November 26, 2001
    Date of Patent: February 3, 2004
    Assignee: Kureha Kagaku Kogyo K. K.
    Inventors: Yoshihiro Arimoto, Yukihiro Sibuya, Masanori Kobayashi, Shigeki Iwamoto
  • Patent number: 6673403
    Abstract: The invention relates a gas barrier multi-layer hollow container having a multi-layer wall structure that a thermoplastic resin layer is laminated on at least one side of a layer formed from polyglycolic acid containing at least 60 wt. % of a repeating unit represented by the following formula (1): wherein the container has excellent oxygen gas barrier property and/or carbon dioxide gas barrier property, and a production process thereof.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: January 6, 2004
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Zenya Shiiki, Yukichika Kawakami, Nobuo Sato, Mitsuru Hoshino, Toshitaka Kouyama
  • Patent number: 6657005
    Abstract: A thermoplastic resin composition is formed by mixing (A) 30-84.9 wt. % of a crystalline thermoplastic resin, (B) 15-65 wt. % of a graft copolymer obtained by graft-polymerizing an ethylenically unsaturated monomer onto a rubber trunk polymer having an alkylene oxide group and (C) 0.1-5 wt. % of an anionic surfactant. As a result, it is possible to obtain a non-black thermoplastic resin composition which shows an antistatic property at a level suitable for use as an ESD (electrical static dissipative) and can be colored into arbitrary hues.
    Type: Grant
    Filed: October 18, 2001
    Date of Patent: December 2, 2003
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Naomitsu Nishihata, Shiro Arai, Chikau Onodera, Masahito Tada
  • Patent number: 6641878
    Abstract: An optical pickup device-holding container, which is formed from a resin composition comprising a poly(arylene sulfide) (A) and an inorganic filler (B) and having a thermal conductivity of at least 1 W/mK; and an optical pickup device in which at least a light source, an objective lens and a light-receiving part are held in the holding container.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: November 4, 2003
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Keiichiro Suzuki, Masahito Tada
  • Patent number: 6610766
    Abstract: The invention relates to polyvinylidene fluoride resin compositions comprising 100 parts by weight of a polyvinylidene fluoride resin, and 0.03 to 10 parts by weight of at least one compound selected from the group consisting of alkyl quaternary ammonium sulfates and alkyl quaternary ammonium sulfites.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: August 26, 2003
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Hideki Kitamura, Satoru Matsunaga, Yoshikichi Teramoto
  • Patent number: 6610853
    Abstract: A herbicide containing as the active ingredient an N-(henylsulfonyl)picolinamide derivative represented by general formula (I) wherein X reprcsents a halogeno, a C1-4 alkyl, a C1-4 haloalkyl, a C1-4 alkoxy, a C1-4 haloalkoxy, a (C1-4 alkoxy)carbonyl, a [di(C1-4 alkyl)amino]sulfonyl, an [N—(C1-4 alkyl)-N—(C1-4 alkoxy)amino]sulfonyl, a (C1-4 alkylamino)sulfonyl, a C1-4 alkylthio, a C1-4 alkylsulfinyl, a C1-4 alkylsulfonyl, or nitro; n is an integer of 0 to 5; Y represets a halogeno, a C1-4 alkyl, a C1-4 haloalkyl, a C1-4 alkoxy, C1-4 haloalkoxy, a C1-4 alkylthio, a C1-4 haloalkylthio, amino, a C1-4 alkylamino, a di(C1-4 alkyl)amino, a (C1-4 alkoxy) C1-4 alkyl, a (C1-4 alkylthio) C1-4 alkyl, or nitro; and m is an integer of 0 to 4.
    Type: Grant
    Filed: August 8, 2000
    Date of Patent: August 26, 2003
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Yoichi Kanda, Koki Sato, Tsutomu Sato
  • Patent number: 6569570
    Abstract: A carbonaceous electrode having improved capacities for doping and dedoping of a cell active substance, such as lithium, and suitable for a non-aqueous secondary battery, is constituted by a carbonaceous material obtained by carbonizing an aromatic condensation polymer formed by condensation of an aromatic compound having a phenolic hydroxy group and an aldehyde. The carbonaceous material is characterized by an atomic ratio H/C between hydrogen atoms and carbon atoms of below 0.1, a carbon dioxide adsorption capacity of at least 10 ml/g, and an X-ray scattering intensity ratio IW/ID of at least 0.25, wherein IW and ID represent scattering intensities as measured in a wet state and a dry state, respectively, at a parameter s=2·sin &thgr;/&lgr; of 0.5 nm−1, wherein &thgr; denotes a scattering angle and &lgr; denotes a wavelength of X-rays in X-ray small-angle scattering measurement.
    Type: Grant
    Filed: October 18, 1999
    Date of Patent: May 27, 2003
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Naohiro Sonobe, Minoru Ishikawa, Jiro Masuko
  • Patent number: 6565985
    Abstract: A polyamide resin-based heat-shrinkable multilayer film is caused to satisfy various properties required of a packaging material, especially a food packaging material, at high levels, and particularly exhibit a highest level of heat-shrinkability. The multilayer film comprises at least three layers including an outer surface layer (a) which comprises a polyester resin or a polyolefin resin; an intermediate layer (b) which comprises a mixture of 85-60 wt. % of an aliphatic polyamide resin, and 15-40 wt. % of an aromatic copolyamide resin which is a copolymer of aliphatic diamine/isophthalic acid and aliphatic diamine/terephthalic acid, and an inner surface layer (c) which essentially comprises a copolymer of ethylene and &agr;-olefin having a density below 0.915. The heat-shrinkable multilayer film has been biaxially stretched and then heat-treated to have hot-water shrinkabilities at 80° C.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: May 20, 2003
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Takahisa Ueyama, Tadayoshi Itoh
  • Patent number: 6562992
    Abstract: The optical material in accordance with the present invention contains a specific phosphonate monoester compound such as monoethyl 3-methoxy butyl phosphonate, and a metal ion such as a copper ion or rare-earth metal ion. They may be contained in a solvent or resin. The use of such a specific phosphonate monoester compound improves the compatibility with a resin, whereby the metal ion can favorably be dispersed into the resin. Consequently, spectral characteristics can be improved when the optical member is formed into a resin-made optical member.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: May 13, 2003
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Naoki Hayashi, Shigeru Mizusawa, Tomoyoshi Koizumi, Katsuichi Machida
  • Patent number: 6545081
    Abstract: A moderately conductive synthetic resin composition comprising a synthetic resin (A), a carbon precursor (B) and at least one conductive filler (C) selected from the group consisting of a non-fibrous conductive filler and a metallic fibrous material, both, having a volume resistivity lower than 102 &OHgr;·cm, and a moderately conductive synthetic resin composition comprising a synthetic resin (A), a carbon precursor (B) and carbon fiber (E).
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: April 8, 2003
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Naomitsu Nishihata, Kiyomi Ohuchi, Masahito Tada
  • Patent number: 6545075
    Abstract: A thermoplastic resin composition improved in compatibility, molding or forming ability, melt-flow properties and mechanical properties, which comprises 100 parts by weight of a resin component containing 40 to 99 wt. % of a poly(arylene sulfide) (A) and 1 to 60 wt. % of polyamide-imide (B), and 0.01 to 10 parts by weight of a silane compound (C) containing at least one functional group selected from the group consisting of amino, ureido, epoxy, isocyanate and mercapto groups.
    Type: Grant
    Filed: May 19, 2000
    Date of Patent: April 8, 2003
    Assignee: Kureha Kagaku Kogyo K.K.
    Inventors: Naomitsu Nishihata, Hiroyuki Sato, Masahito Tada
  • Patent number: 6528567
    Abstract: An anionic surfactant having a thermal weight loss initiation temperature of at least 250° C. is incorporated with a thermoplastic resin comprising a graft copolymer formed by graft-polymerizing an ethylenically unsaturated monomer onto a rubber trunk polymer obtained by emulsion polymerization using a carboxylic acid-type surfactant. As a result, it is possible to obtain an antistatic resin composition which can be effectively produced on an industrial scale and can provide a shaped product excellent in permanent antistatic property and free from haze or discoloration even when processed under severe processing conditions.
    Type: Grant
    Filed: May 3, 2001
    Date of Patent: March 4, 2003
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Shiro Arai, Teruhide Watabe
  • Patent number: 6486099
    Abstract: A microcapsule (or microencapsulated product) having a uniform and smooth coating film and also an excellent performance of gradually liberating the content material is produced at a good particle size distribution while suppressing the occurrence of isolated or aggregated film material, aggregated microcapsules and isolated core material. The production process includes: a first coating step of mixing a water-soluble cationic amino resin and an anionic surfactant in the presence of a hydrophobic core material dispersed in an aqueous medium to coat the dispersed core material with a coacervate of the cationic amino resin and the anionic surfactant; and a second coating step of adding an amino resin prepolymer into an aqueous dispersion liquid containing the coated dispersed core material and polycondensating the amino resin prepolymer to further coat the coated dispersed core material with a polycondensate of the amino resin prepolymer.
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: November 26, 2002
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Yutaka Igari, Yuzi Hori, Tsuneo Okamoto