Patents by Inventor Tokuhiko Handa
Tokuhiko Handa 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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Publication number: 20070081300Abstract: The present invention provides an electrolytic capacitor manufacturing method capable of manufacturing an electrolytic capacitor having the PTC function as easy as possible. A main electrode layer in a cathode is formed so as to have the PTC function. Different from a conventional electrolytic capacitor manufacturing method of connecting a PTC thermistor to a capacitor element to give the PTC function to an electrolytic capacitor so that an electrolytic capacitor manufacturing process is complicated and the number of manufacturing processes is increased by the amount corresponding to the PTC thermistor connecting process, the process of connecting the PTC thermistor to the capacitor element is unnecessary. Consequently, complication of the electrolytic capacitor manufacturing process and increase in the number of manufacturing processes caused by the PTC thermistor connecting process can be prevented.Type: ApplicationFiled: December 6, 2006Publication date: April 12, 2007Applicant: TDK CORPORATIONInventors: Masaaki Kobayashi, Atsushi Monden, Tokuhiko Handa
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Publication number: 20070069848Abstract: A method of manufacturing a PTC element comprising a pair of lead terminals bonded together by thermocompression with a matrix held therebetween comprises a matrix preparing step of preparing a matrix constructed by dispersing a conductive filler into a crystalline polymer; a terminal preparing step of preparing a pair of lead terminals holding the matrix therebetween, a surface of each lead terminal facing the matrix being formed with a plurality of anchor protrusions separated from each other; a flattening step of flattening the anchor protrusions formed in respective nonoverlapping areas in the pair of lead terminals kept from overlapping the matrix; and a thermocompression bonding step of holding the matrix between respective overlapping areas in the pair of lead terminals overlapping the matrix, and securing the pair of lead terminals and the matrix together by thermocompression bonding.Type: ApplicationFiled: September 15, 2006Publication date: March 29, 2007Applicant: TDK CORPORATIONInventors: Hisanao Tosaka, Tokuhiko Handa, Hirokazu Satoh, Tsutomu Hatakeyama
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Publication number: 20070046420Abstract: An object is to provide a PTC element capable of preventing lead terminals from delaminating from an element body. This PTC element 1 is a PTC element comprising an element body 10 in which an electroconductive filler is dispersed in a crystalline polymer, and a pair of terminal electrodes 12, 14 thermocompression-bonded with the element body 10 in between, wherein each of the pair of terminal electrodes 12, 14 has an overlapping region 121, 141 overlapping with the element body 10, and a nonoverlapping region 122, 142 not overlapping with the element body 10, and wherein the nonoverlapping region 122, 142 of each of the pair of terminal electrodes 12, 14 is constructed of a succession of a wide portion 122a a width of which is large across a direction in which the terminal electrode 12, 14 extends from the element body 10, and a narrow portion 122b a width of which is smaller than the width of the wide portion 122a.Type: ApplicationFiled: August 24, 2006Publication date: March 1, 2007Applicant: TDK CORPORATIONInventors: Noriaki Hirano, Kunio Mogi, Tsutomu Hatakeyama, Tsukasa Kon, Tokuhiko Handa, Hisanao Tosaka
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Publication number: 20060231807Abstract: In a first aspect of the present invention, a PTC composition contains (a) a crosslinked polymer matrix having a gel fraction of at least 10%, and (b) an electrically conductive substance. An article shaped therefrom yields an electric resistance of at least 50 m? at 25° C. after being placed in an environment repeating 200 times of a temperature change between ?40° C. and +85° C., and exhibits no thermal deformation when placed on a hot plate at 200° C. for 5 minutes.Type: ApplicationFiled: June 20, 2006Publication date: October 19, 2006Applicant: TDK CORPORATIONInventors: Hisanao Tosaka, Yasuhide Yamashita, Tokuhiko Handa, Katsumi Kobayashi
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Publication number: 20050237148Abstract: The invention provides an organic positive temperature coefficient thermistor provided with a pair of mutually opposing electrodes and a thermistor element with a positive resistance-temperature characteristic situated between the pair of electrodes, wherein said thermistor element contains a cured body derived from a mixture comprising an epoxy resin, a curing agent and conductive particles, and there is included in the epoxy resin and/or curing agent a compound which imparts flexibility to the cured body.Type: ApplicationFiled: March 30, 2005Publication date: October 27, 2005Applicant: TDK CORPORATIONInventors: Yukie Mori, Satoshi Shirai, Tokuhiko Handa
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Publication number: 20050219802Abstract: The present invention provides an electrolytic capacitor manufacturing method capable of manufacturing an electrolytic capacitor having the PTC function as easy as possible. A main electrode layer in a cathode is formed so as to have the PTC function. Different from a conventional electrolytic capacitor manufacturing method of connecting a PTC thermistor to a capacitor element to give the PTC function to an electrolytic capacitor so that an electrolytic capacitor manufacturing process is complicated and the number of manufacturing processes is increased by the amount corresponding to the PTC thermistor connecting process, the process of connecting the PTC thermistor to the capacitor element is unnecessary. Consequently, complication of the electrolytic capacitor manufacturing process and increase in the number of manufacturing processes caused by the PTC thermistor connecting process can be prevented.Type: ApplicationFiled: March 25, 2005Publication date: October 6, 2005Applicant: TDK CORPORATIONInventors: Masaaki Kobayashi, Atsushi Monden, Tokuhiko Handa
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Publication number: 20050200446Abstract: There are provided a process for producing an organic PTC thermistor comprising the steps of: mixing an organic binder with a filler to obtain a mixture; forming on a first conductive foil, a mixture layer comprising the mixture to obtain a laminate; and laminating on the laminate, a second conductive foil or another of the laminate to obtain a sandwich so that the mixture layer can be sandwiched by the opposing conductive foils, wherein at least one of the mixing step, the layer-forming step and the laminating step is conducted under reduced pressure, as well as an organic PTC thermistor obtained by the production process.Type: ApplicationFiled: March 8, 2005Publication date: September 15, 2005Applicant: TDK CorporationInventors: Satoshi Shirai, Yukie Mori, Tokuhiko Handa
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Publication number: 20050024180Abstract: An organic positive temperature coefficient thermistor 10 having at least a pair of electrodes 2 and 3 positioned facing each other and a thermistor element 1 having a positive temperature coefficient of resistance which is positioned between the pair of electrodes 2 and 3, wherein the thermistor element 1 is a molded element consisting of a mixture which contains a polymer matrix and conductive particles having electronic conductivity, and wherein the thermistor element 1 has an amount of oxygen calculated by subtracting the amount of oxygen originally present in the various components of the mixture from the amount of oxygen contained in the thermistor element, which is 1.55 weight percent or less of the mass of the thermistor element.Type: ApplicationFiled: June 23, 2004Publication date: February 3, 2005Applicant: TDK CORPORATIONInventor: Tokuhiko Handa
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Patent number: 6842103Abstract: In an organic PTC thermistor comprising a thermistor body comprising a high-molecular weight organic compound-containing matrix and metal particles, conductive non-metallic fines, typically carbon black, are attached to surfaces of the metal particles. The device has a low room-temperature resistance and a high change rate of resistance, and prevents degradation of its performance during storage under hot humid conditions.Type: GrantFiled: May 23, 2003Date of Patent: January 11, 2005Assignee: TDK CorporationInventors: Yukie Yoshinari, Tokuhiko Handa
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Patent number: 6778062Abstract: In an organic PTC thermistor comprising an organic polymer matrix and conductive metal particles dispersed therein, the conductive metal particles are pretreated with an organic material which is different from the organic polymer matrix, does not covalently bond with the conductive metal particles, and is not compatible at a molecular level with the organic polymer matrix so that an organic material layer covers surfaces of conductive metal particles whereby the stability of thermistor performance is improved.Type: GrantFiled: November 15, 2002Date of Patent: August 17, 2004Assignee: TDK CorporationInventors: Tokuhiko Handa, Yukie Yoshinari
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Publication number: 20040041683Abstract: In a first aspect of the present invention, a PTC composition contains (a) a crosslinked polymer matrix having a gel fraction of at least 10%, and (b) an electrically conductive substance. An article shaped therefrom yields an electric resistance of at least 50 m&OHgr; at 25° C. after being placed in an environment repeating 200 times of a temperature change between −40° C. and +85° C., and exhibits no thermal deformation when placed on a hot plate at 200° C. for 5 minutes.Type: ApplicationFiled: May 27, 2003Publication date: March 4, 2004Applicant: TDK CorporationInventors: Hisanao Tosaka, Yasuhide Yamashita, Tokuhiko Handa, Katsumi Kobayashi
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Publication number: 20030218530Abstract: In an organic PTC thermistor comprising a thermistor body comprising a high-molecular weight organic compound-containing matrix and metal particles, conductive non-metallic fines, typically carbon black, are attached to surfaces of the metal particles. The device has a low room-temperature resistance and a high change rate of resistance, and prevents degradation of its performance during storage under hot humid conditions.Type: ApplicationFiled: May 23, 2003Publication date: November 27, 2003Applicant: TDK CORPORATIONInventors: Yukie Yoshinari, Tokuhiko Handa
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Patent number: 6607679Abstract: In an organic PTC thermistor comprising a matrix of at least two high-molecular weight compounds, a low-molecular weight organic compound, and conductive particles having spiky protuberances, a thermoplastic elastomer is contained in the matrix whereby the thermistor is improved in reliability and performance stability.Type: GrantFiled: January 12, 2001Date of Patent: August 19, 2003Assignee: TDK CorporationInventors: Tokuhiko Handa, Yukie Yoshinari
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Publication number: 20030091829Abstract: In an organic PTC thermistor comprising an organic polymer matrix and conductive metal particles dispersed therein, the conductive metal particles are pretreated with an organic material which is different from the organic polymer matrix, does not covalently bond with the conductive metal particles, and is not compatible at a molecular level with the organic polymer matrix so that an organic material layer covers surfaces of conductive metal particles whereby the stability of thermistor performance is improved.Type: ApplicationFiled: November 15, 2002Publication date: May 15, 2003Applicant: TDK CORPORATIONInventors: Tokuhiko Handa, Yukie Yoshinari
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Patent number: 6558579Abstract: The invention aims to provide an organic PTC thermistor having a lower operating temperature than prior art organic PTC thermistors and exhibiting improved characteristics. The object is attained by an organic PTC thermistor comprising a polymer synthesized in the presence of a metallocene catalyst and conductive particles having spiky protuberances.Type: GrantFiled: April 5, 2001Date of Patent: May 6, 2003Assignee: TDK CorporationInventors: Tokuhiko Handa, Yukie Yoshinari
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Publication number: 20020145130Abstract: The invention aims to provide an organic PTC thermistor having a lower operating temperature than prior art organic PTC thermistors and exhibiting improved characteristics. The object is attained by an organic PTC thermistor comprising a polymer synthesized in the presence of a metallocene catalyst and conductive particles having spiky protuberances.Type: ApplicationFiled: April 5, 2001Publication date: October 10, 2002Applicant: TDK CORPORATIONInventors: Tokuhiko Handa, Yukie Yoshinari
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Patent number: 6452476Abstract: The organic positive temperature coefficient thermistor of the invention comprises a thermosetting polymer matrix, a low-molecular organic compound and conductive particles, each having spiky protuberances, and so can have sufficiently low room-temperature resistance and a large rate of resistance change between an operating state and a non-operating state. In addition, the thermistor can have a small temperature vs. resistance curve hysteresis with no NTC behavior after resistance increases, ease of control of operating temperature, and high performance stability.Type: GrantFiled: January 28, 1999Date of Patent: September 17, 2002Assignee: TDK CorporationInventor: Tokuhiko Handa
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Publication number: 20020093007Abstract: In an organic PTC thermistor comprising a matrix of at least two high-molecular weight compounds, a low-molecular weight organic compound, and conductive particles having spiky protuberances, a thermoplastic elastomer is contained in the matrix whereby the thermistor is improved in reliability and performance stability.Type: ApplicationFiled: January 12, 2001Publication date: July 18, 2002Applicant: TDK CORPORATIONInventors: Tokuhiko Handa, Yukie Yoshinari
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Patent number: 6299801Abstract: The invention provides an organic positive temperature coefficient thermistor comprising at least two polymer matrices, a low-molecular organic compound and a conductive particle having spiky protuberances. For the polymer matrices, at least two thermoplastic polymer matrices having varying melting points or at least one thermoplastic polymer matrix and at least one thermosetting polymer matrix are used. It is thus possible to provide an organic positive temperature coefficient thermistor which has sufficiently low room-temperature resistance and a large rate of resistance change between an operating state and a non-operating state, and can operate with a reduced temperature vs. resistance curve hysteresis, ease of control of operating temperature, and high performance stability.Type: GrantFiled: January 28, 1999Date of Patent: October 9, 2001Assignee: TDK CorporationInventors: Tokuhiko Handa, Yukie Yoshinari
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Patent number: 6143206Abstract: An organic positive temperature coefficient thermistor comprising a thermoplastic polymer matrix, a low-molecular organic compound having a melting point that is equal to or greater than 40.degree. C. and less than 100.degree. C. and conductive particles, each having spiky protuberances, is obtained by crosslinking a milled mixture of these components with a silane coupling agent comprising a vinyl group or a (meth)acryloyl group and an alkoxy group. This organic positive temperature coefficient thermistor has sufficiently low resistance at room temperature and a large rate of resistance change between an operating state and a non-operating state, and can be operated at less than 100.degree. C. with a reduced temperature vs. resistance curve hysteresis, ease of control of operating temperature, and high performance stability.Type: GrantFiled: January 28, 1999Date of Patent: November 7, 2000Assignee: TDK CorporationInventors: Tokuhiko Handa, Yukie Yoshinari