Patents by Inventor Masahiko Kuramoto
Masahiko Kuramoto 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).
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Patent number: 6013726Abstract: A polystyrene-based resin composition containing a styrene-based resin with mainly syndiotactic configuration, a polyamide, and a rubber polymer as main components.Type: GrantFiled: June 5, 1995Date of Patent: January 11, 2000Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Takashi Sumitomo, Keisuke Funaki, Toshikazu Ijitsu, Michihiro Sawada, Masahiko Kuramoto, Masakazu Suzuki
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Patent number: 6008293Abstract: A composition comprising 20-80 weight percent of a styrene polymer with mainly syndiotactic configuration, and 20-80 weight percent of a polycarbonate, and optionally an inorganic filler.Type: GrantFiled: June 5, 1995Date of Patent: December 28, 1999Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Takashi Sumitomo, Keisuke Funaki, Toshikazu Ijitsu, Michihiro Sawada, Masahiko Kuramoto, Masakazu Suzuki
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Patent number: 5990217Abstract: A polystyrene-based resin composition containing a styrene-based resin with mainly syndiotactic configuration and filler as main components. Styrene-based resins of mainly syndiotactic configuration include polystyrene, poly(alkylstyrene), poly(halogenated styrene), poly(alkoxystyrene), styrene copolymers comprised of polymerized units of at least of styrene, alkylstyrene, halogenated styrene and alkoxystyrene, and mixtures thereof.Type: GrantFiled: May 12, 1998Date of Patent: November 23, 1999Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Takashi Sumitomo, Keisuke Funaki, Toshikazu Ijitsu, Michihiro Sawada, Masahiko Kuramoto, Masakazu Suzuki
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Patent number: 5891951Abstract: A polystyrene-based resin composition containing a styrene-based resin with mainly syndiotactic configuration and filler as main components. Styrene-based resins of mainly syndiotactic configuration include polystyrene, poly(alkylstyrene), poly(halogenated styrene), poly(alkoxystyrene), styrene copolymers comprised of polymerized units of at least of styrene, alkylstyrene, halogenated styrene and alkoxystyrene, and mixtures thereof.Type: GrantFiled: June 5, 1995Date of Patent: April 6, 1999Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Takashi Sumitomo, Keisuke Funaki, Toshikazu Ijitsu, Michihiro Sawada, Masahiko Kuramoto, Masakazu Suzuki
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Patent number: 5670587Abstract: There are disclosed a catalyst for producing an aromatic vinyl compound-based polymer composition which catalyst comprises (A) at least two different transition metal compounds each having one .pi.-ligand and (B) an ionic compound comprising a noncoordinate anion and a cation and/or an aluminoxane, and (C) a Lewis acid to be used as the case may be; and a process for producing an aromatic vinyl compound-based polymer composition having a high degree of syndiotactic configuration in its aromatic vinyl chains which process comprises polymerizing an (a) aromatic vinyl compound and (b) an olefinic compound and/or a diolefinic compound in the presence of the above catalyst.Type: GrantFiled: January 23, 1996Date of Patent: September 23, 1997Assignee: Idemitsu Kosan Co., Ltd.Inventors: Mizutomo Takeuchi, Hajime Shouzaki, Norio Tomotsu, Masahiko Kuramoto
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Patent number: 5502133Abstract: Styrene homo-or-co- polymers, the stereoregularity of which is mainly syndiotactic are disclosed, having repeating unit or two or more different repeating units defined by a general formula (I): ##STR1## wherein each R may be the same or different. And a method of preparation of syndiotactic copolymers wherein there are two different repeating units represented by formula (I); wherein the polymerization is carried out with a catalyst comprising (a) a titanium compound and (b) a contact product of an organoaluminum compound and a condensing agent such as water.Type: GrantFiled: April 15, 1993Date of Patent: March 26, 1996Assignee: Idemitsu Kosan Company LimitedInventors: Nobuhide Ishihara, Masahiko Kuramoto, Michitake Uoi
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Patent number: 5430001Abstract: There are disclosed a process for producing a styrene polymer having a high degree of syndiotactic configuration at a reduced cost and an enhanced efficiency, and a catalyst to be used therefor which comprises (A) a specific transition-metal compound, (B) a specific coordination complex compound and (C) a compound having an alkyl group. The catalyst according to the present invention is inexpensive compared with the conventional catalyst containing aluminoxane as the major ingredient, and exhibits a high activity in polymerizing a styrenic monomer into styrene polymer with a high degree of syndiotacticity as well as a high yield and conversion rate.Type: GrantFiled: August 27, 1993Date of Patent: July 4, 1995Assignee: Idemitsu Kosan Co., Ltd.Inventors: Norio Tomotsu, Mizutomo Takeuchi, Masahiko Kuramoto
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Patent number: 5426176Abstract: There is disclosed a process for purifying a styrene polymer which comprises subjecting a highly syntiotactic styrene polymer which is produced by the use of a catalyst composition of (A) an aluminoxane or a specific coordination complex compound and (B) a transition metal compound to deashing treatment at the glass transition temperature of the styrene polymer or higher. The process is capable of efficiently deashing the styrene polymer produced by polymerizing a styrene monomer at a high concentration with a high conversion efficiency. Accordingly, the process greatly improves the productivity of highly pure styrene polymer.Type: GrantFiled: November 3, 1994Date of Patent: June 20, 1995Assignee: Idemitsu Kosan Co., Ltd.Inventors: Hideo Teshima, Masahiko Kuramoto
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Patent number: 5420240Abstract: A process for the purification of a styrene polymer having a high degree of syndiotactivity. The styrene polymer is obtained by carrying out polymerization with a catalyst comprising (A) an aluminoxane and (B) a transition metal compound, which does not contain halogen. The styrene polymer is deashed with an alcoholic alkaline solution and then washed with an alcohol.Type: GrantFiled: March 21, 1994Date of Patent: May 30, 1995Assignee: Idemitsu Kosan Co., Ltd.Inventors: Masahiko Kuramoto, Hideo Teshima
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Patent number: 5395890Abstract: A styrene-based resin composition containing (A) a styrene-based resin with mainly syndiotactic configuration and (B) a thermoplastic resin other than the styrene-based resin exhibit excellent heat resistance and impact resistance. Optionally, the styrene-based resin composition may further contain (C) a rubber polymer and/or (D) an inorganic filler. More particularly, a composition containing 1-98% by weight (A) 1-98% by weight of a styrene-based resin with mainly syndiotactic configuration and 1-98% by weight (B) a polyethylene terephthalate resin or a polyester resin is disclosed.Type: GrantFiled: April 17, 1990Date of Patent: March 7, 1995Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Takashi Sumitomo, Keisuke Funaki, Toshikazu Ijitsu, Michihiro Sawada, Masahiko Kuramoto, Masakazu Suzuki
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Patent number: 5391671Abstract: A styrene copolymer which comprises a styrene repeating unit (a) represented by the general formula (I): ##STR1## and an acrylonitrile repeating unit (b) represented by the general formula (II-(b)): ##STR2## unsaturated carboxylic acid or its ester repeating unit (c) represented by the general formula (II-(c)): ##STR3## or maleimide or N-substituted maleimide (d) represented by the general formula (II-(d)): ##STR4## (in the formula, symbols are the same as defined in the specification) wherein stereoregularity of the styrene repeating unit (a) chain is a high degree of syndiotactic configuration is disclosed.Type: GrantFiled: July 9, 1993Date of Patent: February 21, 1995Assignee: Idemitsu Kosan Co., Ltd.Inventors: Toshinori Tazaki, Masahiko Kuramoto
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Patent number: 5340892Abstract: Disclosed is a process for producing a styrene polymer having a syndiotactic configuration and a wide molecular weight distribution, which is characterized by using as catalyst (a) two or more kinds of titanium compounds and (b) alkylaluminoxane, in the polymerization of styrene monomers.According to the process of the present invention, a styrene polymer which is excellent in physical properties such as heat resistance because of a high syndiotacticity, and also has a wide molecular weight distribution can be obtained. These styrene polymers can be suitably used as materials for various moldings including hollow molding, sheet molding, and film molding.Type: GrantFiled: March 29, 1993Date of Patent: August 23, 1994Assignee: Idemitsu Kosan Co., Ltd.Inventor: Masahiko Kuramoto
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Patent number: 5321122Abstract: There is disclosed a process for purification of a styrene polymer, for purifying a styrene polymer having a high degree of syndiotacticity obtained by using a catalyst comprising (A) aluminoxane and (B) a transition metal compound containing no halogen, deashing the above styrene polymer with an alcoholic alkaline solution and then washing with an alcohol. Also disclosed is a process for purification of a styrene polymer which comprises deashing the above styrene polymer having been produced with a conversion rate of 60% or more after swelling it by adding an aromatic solvent and/or a styrene monomer.According to the process of the present invention, a high purity styrene polymer can be obtained with good efficiency.Type: GrantFiled: October 21, 1992Date of Patent: June 14, 1994Assignee: Idemitsu Kosan Co., Ltd.Inventors: Masahiko Kuramoto, Hideo Teshima
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Patent number: 5272229Abstract: There are disclosed a process for producing a styrene polymer having a high degree of syndiotactic configuration at a reduced cost and an enhanced efficiency, and a catalyst to be used therefore which comprises (A) a specific transition-metal compound, (B) a specific coordination complex compound and (C) a compound having an alkyl group.The catalyst according to the present invention is inexpensive compared with the conventional catalyst containing aluminoxane as the major ingredient, and exhibits a high activity in polymerizing a styrenic monomer into styrene polymer with a high degree of syndiotacticity as well as a high yield and conversion rate.Type: GrantFiled: December 2, 1991Date of Patent: December 21, 1993Assignee: Idemitsu Kosan Co., Ltd.Inventors: Norio Tomotsu, Mizutomo Takeuchi, Masahiko Kuramoto
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Patent number: 5262504Abstract: A styrene copolymer which comprises a styrene repeating unit (a) represented by the general formula (I): ##STR1## and an acrylonitrile repeating unit (b) represented by the general formula (II-(b)): ##STR2## an unsaturated carboxylic acid or its ester repeating unit (c) represented by the general formula (II-(c)): ##STR3## or a maleimide or N-substituted maleimide (d) represented by the general formula (II-(d)): ##STR4## (in the formula, symbols are the same as defined in the specification) wherein stereoregularity of the styrene repeating unit (a) chain is a high degree of syndiotactic configuration is disclosed.Type: GrantFiled: October 19, 1990Date of Patent: November 16, 1993Assignee: Idemitsu Kosan Co., Ltd.Inventors: Toshinori Tazaki, Masahiko Kuramoto
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Patent number: 5260394Abstract: A novel styrene copolymer comprising a styrene repeating unit (a) represented by the general formula: ##STR1## (wherein R.sup.1 is a hydrogen atom or a hydrocarbon group having not more than 20 carbon atoms; n is an integer of 1 to 3 and when n is 2 or 3, R.sup.1 s may be the same or different) and olefin repeating unit (b) represented by the general formula: ##STR2## (wherein R.sup.2 is a hydrogen atom or a saturated hydrocarbon group having not more than 20 carbon atoms) or diene repeating unit, which contains 0.1 to 99.9 wt. % of said olefin repeating unit (b) or diene repeating unit (c) wherein intrinsic viscosity measured in 1,2,4-trichlorobenzene at 135.degree. C. is 0.07 to 20 dl/g and the stereoregularity of the styrene repeating unit chain is a high degree of syndiotactic configuration. This styrene copolymer is excellent in heat resistance and chemical resistance, and further it can be injection molded at low temperature, and has good compatibility with other resine and the like.Type: GrantFiled: October 5, 1990Date of Patent: November 9, 1993Assignee: Idemitsu Kosan Co., Ltd.Inventors: Toshinori Tazaki, Masahiko Kuramoto
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Patent number: 5252693Abstract: Styrene homo-or-co- polymers, the stereoregularity of which is mainly syndiotactic are disclosed, having repeating unit or two or more different repeating units defined by a general formula (I): ##STR1## wherein each R may be the same or different. And a method of preparation of syndiotactic copolymers wherein there are two different repeating units represented by formula (I); wherein the polymerization is carried out with a catalyst comprising (a) a titanium compound and (b) a contact product of a organoaluminum compound and a condensing agent such as water.Type: GrantFiled: April 30, 1991Date of Patent: October 12, 1993Assignee: Idemitsu Kosan Company LimitedInventors: Nobuhide Ishihara, Masahiko Kuramoto, Michitake Uoi
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Patent number: 5247020Abstract: Disclosed is a process for producing a styrene polymer composition, which comprises polymerizing styrene monomer using a catalyst comprising (A) aluminoxane and (B) a compound of the group IV B transition metal in the periodic table, in the presence of rubber-like elastomer.The resin composition obtained thereby is superior in heat resistance, and impact strength, and utilized as the starting material for various moldings.Type: GrantFiled: December 28, 1990Date of Patent: September 21, 1993Assignee: Idemitsu Kosan Co., Ltd.Inventors: Akikazu Nakano, Hideo Teshima, Masahiko Kuramoto
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Patent number: 5212232Abstract: A process for producing a styrene-based polymer, particularly a styrene-based polymer having mainly a syndiotactic structure by polymerizing a styrene-based monomer in the presence of a filler by using a catalyst containing (A) a titanium compound and (B) aluminoxane as main components. The filler acts as a catalyst carrier, increasing catalyst activity, and thus de-ashing treatment is not needed. When the filler is used in a large amount, there is obtained a composition in which the filler is uniformly dispersed in the styrene-based polymer. The styrene-based polymer or styrene-based polymer-containing composition is excellent in heat resistance and chemical resistance.Type: GrantFiled: October 3, 1991Date of Patent: May 18, 1993Assignee: Idemitsu Kosan Co., Ltd.Inventors: Masahiko Kuramoto, Hiroshi Maezawa, Hiroshi Hayashi
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Patent number: RE35289Abstract: A process for production of styrene polymers of high syndiotactic configuration is disclosed, comprising polymerizing styrene or styrene derivatives by the use of a catalyst comprising: (A) a titanium compound, e.g., at least one compound selected from those represented by the formulae: TiR.sup.1.sub.a R.sup.2.sub.b R.sup.3.sub.c X.sup.1.sub.4 -(a+b+c) and TiR.sup.1.sub.d R.sup.2.sub.e X.sup.1.sub.3-(d+e) (all the symbols are as defined in the appended claims); and (B) a contact product of an organoaluminum compound and a condensation agent, e.g., a product resulting from modification of trimethylaluminum with water. Because of such high syndiotactic configuration, the styrene polymers are greater in thermal resistance and solvent resistance than conventional atactic polystyrene.Type: GrantFiled: June 1, 1993Date of Patent: July 2, 1996Assignee: Idemitsu Kosan Company LimitedInventors: Nobuhide Ishihara, Masahiko Kuramoto, Michitake Uoi