Patents by Inventor Toyoaki Ishiwata
Toyoaki Ishiwata 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: 10927226Abstract: The invention provides a prepreg comprising: a primary prepreg composed of reinforcing fibers and a resin composition (I) impregnating the interior of a reinforcing fiber layer formed from these fibers; and a surface layer composed of a resin composition (II) formed on one or both sides of the primary prepreg; wherein the resin composition (I) is an epoxy resin composition [B] containing at least an epoxy resin and a thermoplastic resin, and the resin composition (II) is an epoxy resin composition [A] containing at least an epoxy resin and conductive particles.Type: GrantFiled: September 25, 2013Date of Patent: February 23, 2021Assignee: TOHO TENAX CO., LTD.Inventors: Takaya Suzuki, Hajime Sakamoto, Toyoaki Ishiwata, Yoshitaka Umemoto
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Patent number: 10047478Abstract: The present invention provides a prepreg comprising: a primary pre-pregnant made of a reinforced fiber substrate and an epoxy resin composition containing at least epoxy resin and thermoplastic resin impregnated into the reinforcing fiber that forms the reinforced fiber substrate; and a surface layer made of epoxy resin composition containing at least an epoxy resin and an epoxy resin-soluble thermoplastic resin that dissolves in the epoxy resin, the surface layer being formed on one or both surfaces of the primary prepreg; the prepreg being characterized in that only one of either the epoxy resin composition of the primary prepreg or the epoxy resin composition of the surface layer contains a hardening agent for an epoxy resin.Type: GrantFiled: March 21, 2012Date of Patent: August 14, 2018Assignee: TOHO TENAX CO., LTDInventors: Takaya Suzuki, Toyoaki Ishiwata, Yoshinori Suzuki, Hiroshi Numata
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Publication number: 20150274911Abstract: The invention provides a prepreg comprising: a primary prepreg composed of reinforcing fibers and a resin composition (I) impregnating the interior of a reinforcing fiber layer formed from these fibers; and a surface layer composed of a resin composition (II) formed on one or both sides of the primary prepreg; wherein the resin composition (I) is an epoxy resin composition [B] containing at least an epoxy resin and a thermoplastic resin, and the resin composition (II) is an epoxy resin composition [A] containing at least an epoxy resin and conductive particles.Type: ApplicationFiled: September 25, 2013Publication date: October 1, 2015Inventors: Takaya Suzuki, Hajime Sakamoto, Toyoaki Ishiwata, Yoshitaka Umemoto
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Publication number: 20140057515Abstract: The present invention provides a prepreg comprising: a primary pre-pregnant made of a reinforced fiber substrate and an epoxy resin composition containing at least epoxy resin and thermoplastic resin impregnated into the reinforcing fiber that forms the reinforced fiber substrate; and a surface layer made of epoxy resin composition containing at least an epoxy resin and an epoxy resin-soluble thermoplastic resin that dissolves in the epoxy resin, the surface layer being formed on one or both surfaces of the primary prepreg; the prepreg being characterized in that only one of either the epoxy resin composition of the primary prepreg or the epoxy resin composition of the surface layer contains a hardening agent for an epoxy resin.Type: ApplicationFiled: March 21, 2012Publication date: February 27, 2014Inventors: Takaya Suzuki, Toyoaki Ishiwata, Yoshinori Suzuki, Hiroshi Numata
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Publication number: 20110111663Abstract: Disclosed is an epoxy resin composition comprising at least component [A]: a glycidyl-amino-group-containing polyfunctional epoxy resin, component [B]: an epoxy resin other than the component [A], component [C]: a polyisocyanate compound, component [D]: an aromatic-amine-based curing agent, and component [E]: a thermoplastic resin, characterized in that the epoxy resin composition has an epoxy group concentration of 0.67 to 1.51 Eq/kg of the total amount of the components [A] to [D], and preferably that the component [E] is in a proportion of 10 to 50% by weight of the total epoxy resin composition. Use of a prepreg having the resin composition as a matrix resin makes it possible to obtain a composite material with excellent heat resistance and wet heat resistance together with high mechanical properties.Type: ApplicationFiled: June 6, 2009Publication date: May 12, 2011Applicant: TOHO TENAX CO., LTDInventors: Hironori Kawamoto, Toyoaki Ishiwata
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Publication number: 20100285292Abstract: Disclosed is an aromatic polyimide film having specific elastic modulus and thermal expansion coefficient. Also disclosed is a method for producing such an aromatic polyimide film. Specifically disclosed is an aromatic polyimide film which is composed of an aromatic polyimide containing not less than 70 mol % of repeating units represented by the following formula (I): (I) while satisfying the following relations (1) and (2): CTEMD??11×MiMD+70??(1) CTETD??11×MiTD+70??(2) wherein CTEMD represents the in-plane thermal expansion coefficient (ppm·K?1) in the machine direction; CTETD represents the in-plane thermal expansion coefficient (ppm·K?1) in the transverse direction; MiMD represents the elastic modulus (GPa) in the machine direction; and MiTD represents the elastic modulus (GPa) in the transverse direction. Also specifically disclosed is a method for producing such an aromatic polyimide film.Type: ApplicationFiled: March 27, 2006Publication date: November 11, 2010Inventors: Toyoaki Ishiwata, Jyuhou Matsuo, Nobuaki Kido
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Patent number: 7407702Abstract: A polymetaphenylene isophthalamide-based polymer porous film having a satisfactory porous structure that exhibits excellent gas permeability and heat resistance. It is produced by a process which comprises casting a dope of the polymetaphenylene isophthalamide-based polymer and coagulating it in a coagulating bath. The porous film may also contain inorganic whiskers, and a composite porous film may be formed in combination with a separate thermoplastic polymer film.Type: GrantFiled: February 12, 2004Date of Patent: August 5, 2008Assignee: Teijin LimitedInventors: Takao Ohno, Jiro Sadanobu, Tsutomu Nakamura, Susumu Honda, Toyoaki Ishiwata
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Publication number: 20070148480Abstract: A laminate which is advantageously used as an insulating layer for electronic package application and as an adhesive film for fixing a semiconductor wafer for semiconductor device application, laminates comprising the same and a process for manufacturing the above laminate. The laminate (I) comprises a base layer (A) and an adhesive layer (B) formed on one side or both sides of the layer A, the layer A is a film made of (A-1) a specific wholly aromatic polyimide (PIA-1) or (A-2) a specific wholly aromatic polyamide (PAA-2); and the layer B comprises (B-1) a specific wholly aromatic polyimide (PIB-1), (B-2) a specific wholly aromatic polyamide (PAB-2), or (B-3) a specific resin composition (RCB-3) comprising a wholly aromatic polyimide (PIB-3) and a specific wholly aromatic polyamide (PAB-3), laminates comprising the same and a process for manufacturing the above laminate.Type: ApplicationFiled: December 22, 2004Publication date: June 28, 2007Inventors: Toyoaki Ishiwata, Toru Sawaki, Takashi Yoshitomi, Tsutomu Nakamura
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Publication number: 20070100127Abstract: An oriented polyimide film with a high Young's modulus, satisfactory moist heat resistance and low moisture absorptivity, and a process for its production. The polyimide film is composed mainly of a pyromellitic acid component, with a p-phenylenediamine component at between 30 mole percent and 99 mole percent and a diamine component represented by the structural unit of the following formula (II) at between 1 mole percent and 70 mole percent: (wherein ArIIa and ArIIb are each independently a C6-20 aromatic group optionally having an non-reactive substituent, and X in structural unit (II) consists of at least one group selected from among —O—, —O—ArIIc—O—, —SO2— and —O—ArIId—O—ArIIe—O—), and the polyimide film is characterized by having two perpendicular directions in which the in-plane Young's modulus is 3 GPa or greater, and having a moisture absorptivity of no greater than 3.3 wt % at 72% RH, 25° C.Type: ApplicationFiled: March 31, 2003Publication date: May 3, 2007Inventors: Toyoaki Ishiwata, Tsutomu Nakamura, Kazunori Kojima, Toru Sawaki
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Publication number: 20060134407Abstract: There are provided an adhesive sheet, exhibiting a specific peel strength and shear peel strength and being composed of a base material (A) comprising a fully aromatic polyimide film having a glass transition temperature of 200° C. or above and a thermal adhesive layer (C) comprising a fully aromatic polyamide having a glass transition temperature of 200-500° C., as well as a laminate composed of the sheet and a process for its production. Also provided is a method of release after treatment of the laminate composed of the adhesive sheet, to obtain a laminate having the target to-be-treated layer.Type: ApplicationFiled: January 28, 2004Publication date: June 22, 2006Inventors: Takashi Yoshitomi, Kazunori Kojima, Tsutomu Nakamura, Toyoaki Ishiwata, Toru Sawaki
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Patent number: 6858701Abstract: A wholly aromatic polyester carbonate having a good color and excellent heat resistant stability. This polymer had an extremely low alkali metal content of 10 ppm or less. This polymer is advantageously produced by reacting an aromatic dicarboxylic acid, aromatic diol and diaryl carbonate in a specific molar ratio in the presence of a pyridine-based compound as a catalyst.Type: GrantFiled: May 31, 2001Date of Patent: February 22, 2005Assignee: Teijin LimitedInventors: Hiroshi Sakurai, Toyoaki Ishiwata, Takanori Miyoshi, Shunichi Matsumura
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Patent number: 6812319Abstract: The present invention relates to a wholly aromatic polyester carbonate and a process for its production. An aromatic dicarboxylic acid, an aromatic diol, and a diaryl carbonate are used as starting materials in specific molar ratios, a prepolymerization step, a crystallization step, and a solid-phase polymerization step are essential steps, and a compression molding step is an optional step. This makes it possible to produce with good productivity a wholly aromatic polyester carbonate that has low coloration and a high degree of polymerization.Type: GrantFiled: April 11, 2003Date of Patent: November 2, 2004Assignee: Teijin LimitedInventors: Hiroshi Sakurai, Toyoaki Ishiwata, Shunichi Matsumura, Masayuki Chokai
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Publication number: 20040161598Abstract: A polymetaphenylene isophtha lamide-based polymer porous film having a satisfactory porous structure that exhibits excellent gas permeability and heat resistance. It is produced by a process which comprises casting a dope of the polymetaphenylene isophthalamide-based polymer and coagulating it in a coagulating bath. The porous film may also contain inorganic whiskers, and a composite porous film may be formed in combination with a separate thermoplastic polymer film.Type: ApplicationFiled: February 12, 2004Publication date: August 19, 2004Applicant: TEIJIN LIMITEDInventors: Takao Ohno, Jiro Sadanobu, Tsutomu Nakamura, Susumu Honda, Toyoaki Ishiwata
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Patent number: 6696541Abstract: A method for crystallizing a low molecular weight aromatic polycarbonate effectively and a method for preparing a polycarbonate resin having a desired intrinsic viscosity by using the polycarbonate crystallized with the above method of crystallization. A low molecular weight aromatic polycarbonate (preferably, the one produced by melt polycondensation) is crystallized by bringing it into contact with an aromatic monohydroxy compound or a mixture of said compound and water. Or, a low molecular weight aromatic polycarbonate is melt mixed with at least one or more kinds of compounds selected from the group consisting of aromatic monohydroxy compounds, carbonic acid diester compounds and aromatic dihydroxy compounds to crystallize the low molecular weight aromatic polycarbonate. The crystallized product is heated at a temperature lower than its melting point under reduced pressure or in an inert gas flow to convert it into a high polymerized state.Type: GrantFiled: March 21, 2002Date of Patent: February 24, 2004Assignee: Teijin LimitedInventors: Tomonori Sakurai, Nobuaki Kido, Shunichi Matsumura, Toyoaki Ishiwata, Kazuteru Kohno, Hirotaka Suzuki, Hironori Haga, Toru Hikosaka
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Patent number: 6646060Abstract: A resin composition containing a mixture produced by blending a crystalline polyamide expressed e.g. by formula (1) (in the formula, R1 is a bivalent organic aromatic group or aliphatic group having a carbon number of 2 to 30, optionally having substituent and optionally containing non-reactive groups such as ether group and aromatic group in the main chain, and Ar1 is an aromatic residue having a carbon number of 6 to 45 and optionally having substituent) with a thermoplastic polyester. The resin composition has excellent mechanical characteristics such as high elastic modulus, flow properties and heat-resistance and is suitable as a material for an electronic part for surface mounting.Type: GrantFiled: January 10, 2001Date of Patent: November 11, 2003Assignee: Teijin LimitedInventors: Kiyotsuna Toyohara, Toyoaki Ishiwata, Daisuke Ozaki, Jiro Sadanobu
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Publication number: 20030181627Abstract: A wholly aromatic polyester carbonate having a good color and excellent heat resistant stability. This polymer had an extremely low alkali metal content of 10 ppm or less. This polymer is advantageously produced by reacting an aromatic dicarboxylic acid, aromatic diol and diaryl carbonate in a specific molar ratio in the presence of a pyridine-based compound as a catalyst.Type: ApplicationFiled: December 2, 2002Publication date: September 25, 2003Inventors: Hiroshi Sakurai, Toyoaki Ishiwata, Takanori Miyoshi, Shunichi Matsumura
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Publication number: 20030171528Abstract: The present invention relates to a wholly aromatic polyester carbonate and a process for its production. An aromatic dicarboxylic acid, an aromatic diol, and a diaryl carbonate are used as starting materials in specific molar ratios, a prepolymerization step, a crystallization step, and a solid-phase polymerization step are essential steps, and a compression molding step is an optional step. This makes it possible to produce with good productivity a wholly aromatic polyester carbonate that has low coloration and a high degree of polymerization.Type: ApplicationFiled: April 11, 2003Publication date: September 11, 2003Applicant: TEIJIN LIMITEDInventors: Hiroshi Sakurai, Toyoaki Ishiwata, Shunichi Matsumura, Masayuki Chokai
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Patent number: 6596839Abstract: A process for producing a wholly aromatic polyester which is excellent in heat resistance, mechanical properties and yet color and has a high degree of polymerization by melt polymerizing a dicarboxylic acid and a diol directly on an industrial scale at a low cost in a short period of time without esterifying the dicarboxylic acid or diol in advance. To produce the wholly aromatic polyester by reacting and molding an aromatic dicarboxylic acid such as terephthalic acid, an aromatic diol such as 2,2-bis(4-hydroxyphenyl)propane and a diaryl carbonate by heating, a combination of a specific pyridine compound and an alkali metal (bi)carbonate, a combination of a specific pyridine compound and an organic tin compound or a specific titanium compound is existent as a catalyst. Thereby, the wholly aromatic polyester having the above properties is obtained.Type: GrantFiled: July 8, 2002Date of Patent: July 22, 2003Assignee: Teijin LimitedInventors: Takanori Miyoshi, Hiroshi Sakurai, Toyoaki Ishiwata, Shunichi Matsumura
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Publication number: 20030125504Abstract: A molten product of a wholly aromatic polyester carbonate or wholly aromatic polyester and an aromatic polycarbonate, which is rarely colored even when it is molten at a high temperature. This molten product is used for the production of car parts and electric and electronic parts.Type: ApplicationFiled: December 13, 2002Publication date: July 3, 2003Inventors: Takanori Miyoshi, Hiroshi Sakurai, Shunichi Matsumura, Toyoaki Ishiwata
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Publication number: 20030027972Abstract: A process for producing a wholly aromatic polyester which is excellent in heat resistance, mechanical properties and yet color and has a high degree of polymerization by melt polymerizing a dicarboxylic acid and a diol directly on an industrial scale at a low cost in a short period of time without esterifying the dicarboxylic acid or diol in advance.Type: ApplicationFiled: July 8, 2002Publication date: February 6, 2003Inventors: Takanori Miyoshi, Hiroshi Sakurai, Toyoaki Ishiwata, Shunichi Matsumura