Patents Assigned to Kuraray Company, Limited
  • Patent number: 5466505
    Abstract: Provided are napped fabrics with naps comprising a tapered fiber of a sheath-core polyester fiber with the sheath component having larger alkali hydrolysis rate than the core component, the core of the tapered fiber being exposed at its end part and having smooth surface, the sheath of at least the tapered part having minutely roughened surface. The napped fabrics are of high quality, having good hand and excellent color developing property without unnatural luster such as dark fading or white appearance and being difficult to soil, and are hence markedly suited for car seat cover.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: November 14, 1995
    Assignee: Kuraray Company Limited
    Inventors: Keiji Fukuda, Isao Tokunaga, Takao Akagi
  • Patent number: 5464695
    Abstract: A composite fiber having a single filament fineness of not more than 8 deniers and comprising:a hydrogenation product of a block copolymer comprising poly(vinylaromatic) blocks and poly(conjugated diene) blocks and containing a specific phenol-based compound and a large amount of an inorganic fine powder anda fiber-forming polymer; this composite fiber has, in spite of a large content of the inorganic fine powder and its small fineness, excellent spinnability upon its production and excellent processability after spinning, as well as excellent fiber properties.
    Type: Grant
    Filed: February 27, 1995
    Date of Patent: November 7, 1995
    Assignee: Kuraray Company Limited
    Inventors: Masao Kawamoto, Kazuhiko Tanaka, Kiyoshi Hirakawa, Eiichirou Nakamura
  • Patent number: 5380588
    Abstract: Provided are polyvinyl alcohol-based synthetic fiber having excellent performances as a fiber for FRC that is prepared by autoclave curing and its very effective production processes. One of the processes comprises having a monoaldehyde or a dialdehyde or its acetalization product penetrate into the central region of a polyvinyl alcohol-based synthetic fiber at a first stage and then, at a second stage, effecting crosslinking reaction with a mixed solution containing a monoaldehyde and an acid. The other process comprises conducting acetalization with a bath containing 100 to 250 g/l of formaldehyde and 30 to 80 g/l of sulfuric acid at a temperature of 70.degree. to 100.degree. C. The processes can give a polyvinyl alcohol-based synthetic fiber having a strength of at least 11 g/d, a gel elasticity of at least 6.0.times.10.sup.-3 g/cm.multidot.d and a dissolution ratio of not more than 40% and being able to withstand an autoclave curing at 140.degree. C.
    Type: Grant
    Filed: June 23, 1992
    Date of Patent: January 10, 1995
    Assignee: Kuraray Company Limited
    Inventors: Masakazu Nishiyama, Yasuhiro Harada, Akio Mizobe
  • Patent number: 5340650
    Abstract: A fiber comprising a vinyl alcohol units-containing polymer, said polymer being modified at the oxygen atoms of its alcoholic hydroxyl groups with a group represented by the following formula I ##STR1## wherein M represents a chelate-forming metal atom and R represents an alkyl group. The fiber has excellent resistance to hot water and wet heat and does not stick, adhere or shrink even when dyed at high temperatures or treated by steam ironing, thus proving to be of markedly high commercial value.
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: August 23, 1994
    Assignee: Kuraray Company Limited
    Inventors: Kiyoshi Hirakawa, Izumi Watadani, Kazuhiko Tanaka, Masao Kawamoto, Takaaki Tanaka, Hirohumi Sano, Hayami Yoshimochi, Masahiro Sato
  • Patent number: 5238995
    Abstract: Provided are high-performance polyvinyl alcohol fibers having excellent resistances to hot water and dry heat as well as excellent strength and elastic modulus. The fibers are produced from a highly syndiotactic polyvinyl alcohol containing units from vinyl pivalate in an appropriate amount, which renders it possible to draw the highly crystalline fiber in a high drawing ratio of at least 16.
    Type: Grant
    Filed: September 6, 1990
    Date of Patent: August 24, 1993
    Assignee: Kuraray Company Limited
    Inventors: Yoshiharu Fukunishi, Akitsugu Akiyama, Toshiaki Sato, Hirofumi Sano, Akio Ohmory
  • Patent number: 5110678
    Abstract: Provided is a high-performance PVA fiber and its production.Each filament of the PVA fiber of the present invention having a structure comprising an aggregate of substantially innumerable fibrils, the fiber has high strength, elastic modulus, and resistances to fatigue, hot water and chemicals and can be pulpified while keeping its excellent features such as high strength. The PVA fiber of the present invention cannot, even drawn to a high ratio, be readily whitened by virtue of its fibril-aggregate structure, and can hence be made still higher in performances. The PVA fiber can be obtained by adding to a PVA solution a relatively large amount of surface active agent, and wet or dry-jet-wet spinning the thus prepared dope solution into an aqueous alkaline coagulating bath.
    Type: Grant
    Filed: April 20, 1990
    Date of Patent: May 5, 1992
    Assignee: Kuraray Company Limited
    Inventors: Hiroshi Narukawa, Akio Mizobe, Fumio Nakahara, Akira Kubotsu, Akitsugu Akiyama, Masakazu Nishiyama, Kenji Nagamatu, Hirotoshi Miyazaki
  • Patent number: 5089553
    Abstract: The present invention relates to a novel copolymerized composition characterized in that it comprises (A) 100 parts by weight of a copolymerized polyester containing (a) an aromatic dicarboxylic acid unit composed mainly of a terephthalic acid unit, (b) a glycol unit composed mainly of an ethylene glycol unit, (c) a polytetramethylene glycol unit, (d) a polyethylene glycol unit and (e) an aliphatic dicarboxylic acid unit having 9 or more carbon atoms, (B) 5 to 150 parts by weight of a reinforcing substance and (C) 1 to 10 parts by weight of a metal salt of an ionic copolymer.The copolymerized polyester compositions of the present invention retain excellent heat resistance and rigidity that the glass fiber-reinforced polyethylene terephthalate compositions possess originally and are considerably improved in terms of low-temperature moldability, toughness, alkali resistance and like other factors.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: February 18, 1992
    Assignees: Idemitsu Petrochemical Co., Ltd., Kuraray Company Limited
    Inventors: Takashi Umeda, Seiichi Zemba, Kazuo Hara, Katsunori Takamoto, Shinichi Yokota
  • Patent number: 5087519
    Abstract: Provided is a composite fiber comprising an ethylene-vinyl alcohol copolymer and a thermoplastic polymer. The composite fiber is acetalized with a dialdehyde such that the ethylene-vinyl alcohol copolymer has a melting point in a specified range, whereby the composite fiber does not cause serious stickings between the filaments when dyed, sewn or ironed and is excellent in hydrophilic property, resistance to soiling, antistatic property and the like. The composite fiber is thus very suitable for clothing use.
    Type: Grant
    Filed: December 1, 1989
    Date of Patent: February 11, 1992
    Assignee: Kuraray Company Limited
    Inventors: Shinji Yamaguchi, Kiyoshi Hirakawa, Seiji Kashima, Kazuhiko Tanaka, Masao Kawamoto, Takao Akagi
  • Patent number: 5064495
    Abstract: There is provided an adhesive comprising (a) a compound having at least one mercapto group or polysulfide group joined to a saturated carbon atom and at least one olefinic double bond and (b) a solvent which does not copolymerize with said compound or a liquid polymerizable monomer which copolymerizes with said compound.
    Type: Grant
    Filed: July 13, 1989
    Date of Patent: November 12, 1991
    Assignee: Kuraray Company, Limited
    Inventors: Ikuo Omura, Junichi Yamauchi, Mitsunobu Kawashima
  • Patent number: 5047288
    Abstract: Provided is a moldable sheet comprising a synthetic organic fiber nonwoven fabric for reinforcing resinous molded article and a resin composition having impregnated the nonwoven fabric. The nonwoven fabric comprises opened single filaments having a specific fineness and bundles of filaments laid parallel with one another having a specific total fineness distribution, said single filaments and said bundles of filaments being bonded with a binder of non-fiber form. By employing this construction, the nonwoven fabric can, when used for reinforcing resinous article, improve the impact resistance, i.e. falling ball impact resistance and Izod impact resistance, which have been poor with conventional glass-fiber reinforced resinous shaped articles, while maintaining the high mechanical strength of the resinous article.
    Type: Grant
    Filed: March 28, 1990
    Date of Patent: September 10, 1991
    Assignee: Kuraray Company Limited
    Inventors: Hideki Hoshiro, Hironao Funabiki, Kenji Saimen, Toshihide Ohigashi, Hiroshi Sugishima
  • Patent number: 5047448
    Abstract: The present invention provides shaped articles incorporating mixed particulate metals comprising fine particles of a first metal or a compound thereof capable of releasing a metal ion having a first antimicrobial function, and a second metal having an ionization tendency different from that of the first metal or a compound thereof capable of releasing a metal ion having a second antimicrobial function, together with a polyester compound having specific properties, dispersed therein, and thus being capable of effectively releasing gradually over a long period a trace amount of the metal ions having an antimicrobial function from the particulate metals and maintaining an excellent antimicrobial function. The fibers according to the present invention also have excellent durability of the antimicrobial function and have excellent mildew resistance, in repeated washings and in service.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: September 10, 1991
    Assignee: Kuraray Company Limited
    Inventors: Kazuhiko Tanaka, Kiyoshi Hirakawa, Kiyoshi Takisawa, Takao Akagi, Masao Kawamoto
  • Patent number: 5009946
    Abstract: There is described a composite sheet includes a textile layer containing an electrically conductive fiber with an electric resistance of 10.sup.5 to 10.sup.9 ohms/cm as disposed at spaced intervals not exceeding 30 mm and a semiconductive layer with a surface resistivity of 10.sup.6 to 10.sup.10 ohms as disposed on the reverse side of the textile layer. This composite sheet releases the static electricity of the charged body on mutual contact and is therefore suitable for use as a car upholstery material and particularly as a seat covering material.
    Type: Grant
    Filed: December 15, 1989
    Date of Patent: April 23, 1991
    Assignees: Kuraray Company Limited, Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Isamu Hatomoto, Yoshiteru Matsuo
  • Patent number: 4987194
    Abstract: A block copolymer having a numerical average molecular weight of 30,000 to 300,000 composed of two or more blocks consisting of aromatic vinyl units having a numerical average molecular weight of 2500 to 40,000, and one or more blocks containing a vinyl bonding content of not less than 40%, having a peak temperature of primary dispersion of tan .delta. at least 0.degree. C., and consisting of isoprene or isoprene-butadiene units in which at least a part of carbon-carbon double bonds may be hydrogenated, and a composition consisting of the block copolymer. The composition can provide a vibration-damping material.
    Type: Grant
    Filed: September 22, 1989
    Date of Patent: January 22, 1991
    Assignee: Kuraray Company, Limited
    Inventors: Miduho Maeda, Hideo Takamatsu, Masao Ishii, Shobu Minatono
  • Patent number: 4968561
    Abstract: A synthetic fiber suited for use as a reinforcement for cement mortar or concrete as derived from monofilaments having a tensile strength of not less than 80 kg/mm.sup.2, Young's modulus of not less than 2,300 kg/mm.sup.2, a flat cross section in which the minor axis-to-major axis ratio is 1:2 to 1:10, and a fineness of 1,000-9,000 denier, and being cut to a fiber length such that the aspect ratio (the value obtained by dividing the fiber length by the diameter of a circle equivalent in area to the cross section of the fiber) amounts to 20-150, in particular a polyvinyl alcohol fiber having the above-mentioned characteristic features, shows good dispersibility in cement mortar and produces very good reinforcing effect. Materials of construction which are excellent in workability and postcure strength can be obtained by incorporating the above-mentioned fiber to cement and the like.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: November 6, 1990
    Assignee: Kuraray Company Limited
    Inventors: Akio Mizobe, Masaki Okazaki, Mitsuro Mayahara, Junichi Yoshinaka
  • Patent number: 4942089
    Abstract: Rapidly shrinking fibers hardly soluble in water and capable of shrinking in water at 20.degree. C. by not less than 30% in not longer than 10 seconds are obtained, for example, by spinning, drawing and heat-treating a carboxy-modified polyvinyl alcohol under specific conditions. Yarns made from a fiber of this kind in conjunction with a fiber slowing shrinking in water as well as nonwoven fabrics made by incorporating yarns containing said rapidly shrinking fibers in nonwoven fabric shrinkable upon absorption of water are suited as means of tightly fitting edge portions of disposable diapers to the thigh.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: July 17, 1990
    Assignee: Kuraray Company Limited
    Inventors: Tsuneo Genba, Junichi Yoshinaka, Shingo Nakanishi
  • Patent number: 4809493
    Abstract: Rapidly shrinking fibers hardly soluble in water and capable of shrinking in water at 20.degree. C. by not less than 30% in not longer than 10 seconds are obtained, for example, by spinning, drawing and heat-treating a carboxy-modified polyvinyl alcohol under specific conditions. Yarns made from a fiber of this kind in conjunction with a fiber slowing shrinking in water as well as nonwoven fabrics made by incorporating yarns containing said rapidly shrinking fibers in nonwoven fabric shrinkable upon absorption of water are suited as means of tightly fitting edge portions of disposable diapers to the thigh.
    Type: Grant
    Filed: October 21, 1986
    Date of Patent: March 7, 1989
    Assignee: Kuraray Company Limited
    Inventors: Tsuneo Genba, Junichi Yoshinaka, Shingo Nakanishi
  • Patent number: 4746586
    Abstract: The use of a paper containing synthetic fiber not greater than 0.8 denier, particularly a paper consisting of a polyvinyl alcohol fiber not greater than 0.8 denier and a cellulosic fiber, as a separator in an alkaline dry cell is conductive to improved alkali resistance, greater alkaline electrolyte absorption, and prevention of an internal short-circuit, resulting in a marked improvement in the discharge capacity of the dry battery.
    Type: Grant
    Filed: December 9, 1986
    Date of Patent: May 24, 1988
    Assignee: Kuraray Company Limited
    Inventors: Kazuo Mizutani, Shoichi Murakami
  • Patent number: 4657973
    Abstract: Polycarbonate resin compositions are disclosed, comprising: (1) (A) a polycarbonate resin and (B) polyesterether elastomer, said elastomer composing of a bifunctional carboxylic acid component and a glycol component comprising polyalkylene glycol and ethylene glycol, or (2) the components (A) and (B), and (C) a rubber-like elastomer, or (3) the components (A) and (B), and (D) a polyester resin, or (4) the components (A), (B), (C) and (D). These compositions are excellent in solvent resistance and so forth, and further possess excellent physical and thermal properties characteristic of a polycarbonate resin. Thus the compositions are useful for use in production of industrial and electrical articles, such as a car bumper in the field of car industry.
    Type: Grant
    Filed: January 8, 1986
    Date of Patent: April 14, 1987
    Assignees: Idemitsu Petrochemical Co., Ltd., Kuraray Company Limited
    Inventors: Hideki Endo, Kazuto Hashimoto, Kenji Tanaka, Takeshi Matsumoto, Keishiro Igi, Takayuki Okamura, Shunro Taniguchi, Masao Ishii, Yoshifumi Murata, Shinichi Yokota
  • Patent number: 4612157
    Abstract: A fine-denier, high-tenacity, water-resistant polyvinyl alcohol fiber is produced by dissolving a polyvinyl alcohol having an average degree of polymerization between 1,200 and 3,000, boric acid or a salt thereof in a proportion of 0.5 to 5 weight percent relative to said polyvinyl alcohol and an acid for adjusting a final spinning solution to pH 5 or less in water to prepare an aqueous solution containing 8 to 14 weight percent of said polyvinyl alcohol, discharging said aqueous solution as said spinning dope from a spinneret nozzle having an average orifice diameter of 0.02 to 0.04 millimeters into a bath comprising an aqueous solution containing alkali and dehydrating salt at a bath draft within a range of 10 to -60 percent, and finally stretching the resulting tow at least 10-fold. The fine-denier fiber thus obtained has a marked reinforcing effect on various materials, particularly inorganic hydraulic materials such as cement.
    Type: Grant
    Filed: January 11, 1985
    Date of Patent: September 16, 1986
    Assignee: Kuraray Company, Limited
    Inventors: Tsuneo Genba, Akio Mizobe, Masaki Okazaki, Isao Sakuragi
  • Patent number: 4593145
    Abstract: A process for producing isoprene in good yield is provided. The process is characterized in that an alkyl tertiary butyl ether and a formaldehyde source are fed, together with water, into a acidic aqueous solution continuously or intermittently while maintaining the reaction pressure in an adequate range and at the same time distilling off the product isoprene, unreacted starting materials, isobutene and tertiary butanol, together with water, from the reaction zone.
    Type: Grant
    Filed: March 4, 1985
    Date of Patent: June 3, 1986
    Assignee: Kuraray Company Limited
    Inventors: Yoichi Ninagawa, Osamu Yamada, Tsumoru Renge, Sunao Kyo, Takayoshi Osaki, Koichi Kushida