Patents by Inventor Shojiro Kuwahara
Shojiro Kuwahara 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: 9085647Abstract: A thermoplastic transparent resin which is produced by hydrogenating 70% or more of aromatic double bonds of a copolymer. The copolymer is produced by polymerizing a monomer composition containing at least one (meth)acrylic ester monomer and at least one aromatic vinyl monomer and has a molar ratio (A/B) of from 1 to 4 wherein A is a molar amount of a constitutional unit derived from the (meth)acrylic ester monomer and B is a molar amount of a constitutional unit derived from the aromatic vinyl monomer. The thermoplastic transparent resin is suitable for the production of a molded article such as optical article having a good color tone because molding defect is less produced.Type: GrantFiled: May 31, 2005Date of Patent: July 21, 2015Assignee: MITSUBISHI GAS CHEMICAL COMPANY, INC.Inventors: Nobuya Saegusa, Shojiro Kuwahara
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Patent number: 8030434Abstract: The present invention relates to a polyester film produced by melt-extruding a polyester composed of a dicarboxylic acid unit and a diol unit, wherein 1 to 80 mol % of the diol unit is a unit containing a cyclic acetal skeleton, and the polyester film has an in-plane retardation of 20 nm or less at a wavelength of 550 nm. The polyester film is an optically isotropic polyester film which is easily produced by an extrusion-molding method and has an economical advantage. The polyester film is useful for production of optical members or optical products such as phase difference films, protective films for polarizing plates, light diffusion films, lens sheets, anti-reflection films and optical information recording media.Type: GrantFiled: January 31, 2006Date of Patent: October 4, 2011Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Tsuyoshi Ikeda, Koshi Koide, Nobuyuki Koike, Tadashi Kawabata, Takeshi Hirokane, Shojiro Kuwahara
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Patent number: 7910659Abstract: Disclosed is an acrylic syrup containing a vinyl monomer (A) of methyl methacrylate and a polymerized solid component (B) which is a high polymer of said vinyl monomer and has a weight average molecular weight of from 30,000 to 2,000,000 as measured by the GPC and a viscosity at 25° C. of from 0.1 to 50 Pa·s, wherein at least part of said polymerized solid component (B) is a grafted rubber obtained by graft-polymerizing said vinyl monomer with a rubbery polymer, and said grafted rubber has a large branching coefficient. The acrylic resin molded articles obtained from the acrylic syrup exhibit excellent impact resistance.Type: GrantFiled: October 24, 2005Date of Patent: March 22, 2011Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Tadashi Kawabata, Shojiro Kuwahara, Masahiro Kurokawa
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Publication number: 20080213606Abstract: A thermoplastic transparent resin which is produced by hydrogenating 70% or more of aromatic double bonds of a copolymer. The copolymer is produced by polymerizing a monomer composition containing at least one (meth)acrylic ester monomer and at least one aromatic vinyl monomer and has a molar ratio (A/B) of from 1 to 4 wherein A is a molar amount of a constitutional unit derived from the (meth)acrylic ester monomer and B is a molar amount of a constitutional unit derived from the aromatic vinyl monomer. The thermoplastic transparent resin is suitable for the production of a molded article such as optical article having a good color tone because molding defect is less produced.Type: ApplicationFiled: May 31, 2005Publication date: September 4, 2008Inventors: Nobuya Saegusa, Shojiro Kuwahara
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Patent number: 7192994Abstract: Disclosed is a method of producing a powdery coating material by using: a curable polyester resin (A) having a hydroxyl group and/or a carboxyl group at the terminals thereof, and further having a number average molecular weight of from 1,000 to 30,000, a glass transition temperature of from 30 to 100° C.; a curing agent (B) which is solid at normal temperature and is capable of being reacted with the hydroxyl group or the carboxyl group of the curable polyester resin (A); and a solvent (C) having a boiling point under normal pressure of from 50 to 130° C.; and comprising a step of kneading the curable polyester resin (A), the curing agent (B) and the solvent (C) under condition in which at 50 to 130° C., not less than 20% by weight of the curing agent (B) is dissolved in the solvent and, then, vapor-removing the solvent (C) under a reduced pressure.Type: GrantFiled: October 12, 2004Date of Patent: March 20, 2007Assignee: Mitsubishi Gas Chemical Co., Inc.Inventors: Nobuyuki Koike, Shojiro Kuwahara
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Patent number: 7183362Abstract: In the invention, a polyester resin comprising dicarboxylic acid constitutional units and diol constitutional units wherein 5 to 60 mol % of the diol constitutional units has a cyclic acetal skeleton is produced by a process comprising an oligomerization step and a polymerization step. In the oligomerization step, an ester having a limited acid value is transesterified with a diol having a cyclic acetal skeleton in the presence of a basic compound to obtain an oligomer. The oligomer is then polymerized in the subsequent polymerization step to increase the molecular weight.Type: GrantFiled: November 29, 2004Date of Patent: February 27, 2007Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Takeshi Hirokane, Shojiro Kuwahara, Tsuyoshi Ikeda, Nobuya Saegusa, Tomohito Oyama
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Patent number: 7179869Abstract: In the invention, a polyester resin having dicarboxylic acid constitutional units and diol constitutional units wherein 5 to 60 mol % of the diol constitutional units has a cyclic acetal skeleton is produced by a process including an oligomerization step and a polymerization step. In the oligomerization step, an ester having a limited acid value is transesterified with a diol having a cyclic acetal skeleton in the presence of a titanium compound to obtain an oligomer. The oligomer is then polymerized in the subsequent polymerization step to increase the molecular weight.Type: GrantFiled: March 11, 2005Date of Patent: February 20, 2007Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Takeshi Hirokane, Tomohito Oyama, Shojiro Kuwahara
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Patent number: 7064169Abstract: Polyester resin composition (C) comprises polyester resin (A), which comprises polyester resin (l) comprising a diol unit having a cyclic acetal structure (CA) and a dicarboxylic acid unit having no CA, polyester resin (m) comprising a dicarboxylic acid unit having CA and a diol unit having no CA and/or polyester resin (n) comprising a diol unit having CA and a dicarboxylic acid unit having CA, and polyester resin (B) having no CA. The sum of the fraction of the dicarboxylic acid unit having CA in the entire dicarboxylic acid unit and the fraction of the diol unit having CA in the entire diol unit in composition (C) is 0.05% by mole or greater. The polyester resin compositions are excellent in transparency, melt viscoelasticity, heat resistance and moldability, and exhibit a samll crystallization rate.Type: GrantFiled: December 19, 2002Date of Patent: June 20, 2006Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Tsuyoshi Ikeda, Takeshi Hirokane, Shojiro Kuwahara
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Patent number: 7056984Abstract: Disclosed is an acrylic syrup containing a vinyl monomer (A) of methyl methacrylate and a polymerized solid component (B) which is a high polymer of said vinyl monomer and has a weight average molecular weight of from 30,000 to 2,000,000 as measured by the GPC and a viscosity at 25° C. of from 0.1 to 50 Pa·s, wherein at least part of said polymerized solid component (B) is a grafted rubber obtained by graft-polymerizing said vinyl monomer with a rubbery polymer, and said grafted rubber has a large branching coefficient. The acrylic resin molded articles obtained from the acrylic syrup exhibit excellent impact resistance.Type: GrantFiled: May 15, 2002Date of Patent: June 6, 2006Assignee: Mitsubishi Gas Chemical Co., Inc.Inventors: Tadashi Kawabata, Shojiro Kuwahara, Masahiro Kurokawa
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Publication number: 20060089463Abstract: Disclosed is an acrylic syrup containing a vinyl monomer (A) of methyl methacrylate and a polymerized solid component (B) which is a high polymer of said vinyl monomer and has a weight average molecular weight of from 30,000 to 2,000,000 as measured by the GPC and a viscosity at 25° C. of from 0.1 to 50 Pa·s, wherein at least part of said polymerized solid component (B) is a grafted rubber obtained by graft-polymerizing said vinyl monomer with a rubbery polymer, and said grafted rubber has a large branching coefficient. The acrylic resin molded articles obtained from the acrylic syrup exhibit excellent impact resistance.Type: ApplicationFiled: October 24, 2005Publication date: April 27, 2006Inventors: Tadashi Kawabata, Shojiro Kuwahara, Masahiro Kurokawa
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Publication number: 20050218550Abstract: Disclosed is a method of producing a powdery coating material by using: a curable acrylic resin (A) having a number average molecular weight of from 2,000 to 20,000 and a glass transition temperature of from 30 to 90° C. obtained by polymerizing a starting monomer containing from 15 to 50 mol % of an unsaturated compound which contains at least a glycidyl group and/or a methylglycidyl group, and from 20 to 50 mol % of methyl methacrylate; a curing agent (B) capable of being reacted with the glycidyl group or the methylglycidyl group constituting the curable acrylic resin (A); and an alcohol solvent (C) having a boiling point under normal pressure of from 70 to 120° C.; said method comprising a kneading step of so kneading the curable acrylic resin (A), the curing agent (B) and the alcohol solvent (C) that at least the curing agent (B) is dissolved in the alcohol solvent (C) at a temperature of not higher than 130° C.Type: ApplicationFiled: June 3, 2005Publication date: October 6, 2005Inventors: Nobuyuki Koike, Shojiro Kuwahara
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Publication number: 20050209435Abstract: In the invention, a polyester resin having dicarboxylic acid constitutional units and diol constitutional units wherein 5 to 60 mol % of the diol constitutional units has a cyclic acetal skeleton is produced by a process including an oligomerization step and a polymerization step. In the oligomerization step, an ester having a limited acid value is transesterified with a diol having a cyclic acetal skeleton in the presence of a titanium compound to obtain an oligomer. The oligomer is then polymerized in the subsequent polymerization step to increase the molecular weight.Type: ApplicationFiled: March 11, 2005Publication date: September 22, 2005Inventors: Takeshi Hirokane, Tomohito Oyama, Shojiro Kuwahara
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Patent number: 6933348Abstract: Disclosed is a method of producing a powdery coating material by using a curable acrylic resin (A) having a number average molecular weight of from 2,000 to 20,000 and a glass transition temperature of from 30 to 90° C. obtained by polymerizing a starting monomer containing from 15 to 50 mol % of an unsaturated compound which contains at least a glycidyl group and/or a methylglycidyl group, and from 20 to 50 mol % of methyl methacrylate; a curing agent (B) capable of being reacted with the glycidyl group or the methylglycidyl group constituting the curable acrylic resin (A); and an alcohol solvent (C) having a boiling point under normal pressure of from 70 to 120° C.; said method comprising a kneading step of so kneading the curable acrylic resin (A), the curing agent (B) and the alcohol solvent (C) that at least the curing agent (B) is dissolved in the alcohol solvent (C) at a temperature of not higher than 130°C.Type: GrantFiled: March 13, 2002Date of Patent: August 23, 2005Assignee: Mitsubishi Gas Chemical Co., Inc.Inventors: Nobuyuki Koike, Shojiro Kuwahara
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Publication number: 20050176914Abstract: In the invention, a polyester resin comprising dicarboxylic acid constitutional units and diol constitutional units wherein 5 to 60 mol % of the diol constitutional units has a cyclic acetal skeleton is produced by a process comprising an oligomerization step and a polymerization step. In the oligomerization step, an ester having a limited acid value is transesterified with a diol having a cyclic acetal skeleton in the presence of a basic compound to obtain an oligomer. The oligomer is then polymerized in the subsequent polymerization step to increase the molecular weight.Type: ApplicationFiled: November 29, 2004Publication date: August 11, 2005Inventors: Takeshi Hirokane, Shojiro Kuwahara, Tsuyoshi Ikeda, Nobuya Saegusa, Tomohito Oyama
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Patent number: 6927275Abstract: The process of the present invention for producing a polyester resin comprising a dicarboxylic acid constitutional unit and a diol constitutional unit having a cyclic acetal skeleton comprises a step (1) of subjecting a diol (A) having a cyclic acetal skeleton and an ester (D) to transesterification reaction and a step (2) of mainly converting the resultant oligomer into a high polymer. The step (1) simultaneously satisfies the requirements (i) to (iv) as described in the specification. In the process of the present invention, the polyester resins having excellent moldability and mechanical properties are stably produced by a transesterification method which is less detrimental to environments.Type: GrantFiled: September 11, 2003Date of Patent: August 9, 2005Assignee: Mitsubishi Gas Chemical Co., Inc.Inventors: Takeshi Hirokane, Tsuyoshi Ikeda, Shojiro Kuwahara, Takamasa Kawashima, Tomohito Oyama
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Publication number: 20050113490Abstract: Disclosed is a method of producing a powdery coating material by using: a curable polyester resin (A) having a hydroxyl group and/or a carboxyl group at the terminals thereof, and further having a number average molecular weight of from 1,000 to 30,000, a glass transition temperature of from 30 to 100° C.; a curing agent (B) which is solid at normal temperature and is capable of being reacted with the hydroxyl group or the carboxyl group of the curable polyester resin (A); and a solvent (C) having a boiling point under normal pressure of from 50 to 130° C.; and comprising a step of kneading the curable polyester resin (A), the curing agent (B) and the solvent (C) under condition in which at 50 to 130° C., not less than 20% by weight of the curing agent (B) is dissolved in the solvent and, then, vapor-removing the solvent (C) under a reduced pressure.Type: ApplicationFiled: October 12, 2004Publication date: May 26, 2005Inventors: Nobuyuki Koike, Shojiro Kuwahara
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Patent number: 6822022Abstract: Disclosed is a method of producing a powdery coating material by using: a curable polyester resin (A) having a hydroxyl group and/or a carboxyl group at the terminals thereof, and further having a number average molecular weight of from 1,000 to 30,000, a glass transition temperature of from 30 to 100° C.; a curing agent (B) which is solid at normal temperature and is capable of being reacted with the hydroxyl group or the carboxyl group of the curable polyester resin (A); and a solvent (C) having a boiling point under normal pressure of from 50 to 130° C.; and comprising a step of kneading the curable polyester resin (A), the curing agent (B) and the solvent (C) under condition in which at 50 to 130° C., not less than 20% by weight of the curing agent (B) is dissolved in the solvent and, then, vapor-removing the solvent (C) under a reduced pressure.Type: GrantFiled: March 13, 2002Date of Patent: November 23, 2004Assignee: Mitsubishi Gas Chemical INCInventors: Nobuyuki Koike, Shojiro Kuwahara
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Publication number: 20040167309Abstract: The monomer of the present invention is represented by the following Formula 1: 1Type: ApplicationFiled: March 1, 2004Publication date: August 26, 2004Inventors: Nobuya Saegusa, Akihiro Honma, Hajime Yamada, Takamasa Kawashima, Shojiro Kuwahara
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Publication number: 20040059084Abstract: The process of the present invention for producing a polyester resin comprising a dicarboxylic acid constitutional unit and a diol constitutional unit having a cyclic acetal skeleton comprises a step (1) of subjecting a diol (A) having a cyclic acetal skeleton and an ester (D) to transesterification reaction and a step (2) of mainly converting the resultant oligomer into a high polymer. The step (1) simultaneously satisfies the requirements (i) to (iv) as described in the specification. In the process of the present invention, the polyester resins having excellent moldability and mechanical properties are stably produced by a transesterification method which is less detrimental to environments.Type: ApplicationFiled: September 11, 2003Publication date: March 25, 2004Inventors: Takeshi Hirokane, Tsuyoshi Ikeda, Shojiro Kuwahara, Takamasa Kawashima, Tomohito Oyama
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Patent number: 6653440Abstract: In the production method of the present invention, a copolyester of intended sublimable diol proportion is produced by the reaction of a dicarboxylic acid and/or an ester-forming derivative thereof with a sublimable diol and a non-sublimable diol with an increased conversion of the sublimable diol. Since the escape of the sublimable diol is effectively prevented, the process solves the problem of clogging pressure-reduced pipes, etc. of an apparatus for polyester resin production.Type: GrantFiled: November 6, 2002Date of Patent: November 25, 2003Assignee: Mitsubishi Gas Chemical CompanyInventors: Takeshi Hirokane, Tsuyoshi Ikeda, Shojiro Kuwahara