Patents by Inventor Hiromasa Yamamoto

Hiromasa Yamamoto 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).

  • Patent number: 6861552
    Abstract: The present invention discloses an adamantyl ester monomer composition characterized by containing at least an adamantyl ester monomer having at least one polymerizable unsaturated bond in the molecule, and a compound represented by the following general formula (1): (in the formula, R1 is an alkyl group of 1 to 5 carbon atoms, R2 is an alkyl group of 1 to 5 carbon atoms, R3 is a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, and R4 is a hydrogen atom or a methyl group). The composition has high storage stability and, by subjecting it to distillation, an adamantyl ester monomer of high purity can be obtained easily.
    Type: Grant
    Filed: July 18, 2001
    Date of Patent: March 1, 2005
    Assignee: Tokuyama Corporation
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Yoshihiro Hirota
  • Patent number: 6852885
    Abstract: There is provided a method for obtaining a target organic compound such as an alkyladamantyl ester efficiently by purifying a crude organic compound which contains, as impurities, sublimable materials which start to sublime at temperatures lower than a boiling point of the target organic compound by use of such a simple method as distillation during its production process, without being adversely affected by adherence of the sublimable materials. The distillation is carried out in the presence of a compound having a boiling point which is lower than a boiling point of the target organic compound, e.g., a carbonyl-group-containing compound. For example, 2-methyl-2-adamantyl methacrylate (boiling point: 92° C./0.3 mmHg) containing sublimable impurities such as adamantane (sublimation starting temperature: room temperature or lower) is distilled in the presence of 1,3-dimethyl-2-imidazolidinone (boiling point: 225° C.).
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: February 8, 2005
    Assignee: Tokuyama Corporation
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Hideki Kikuchi
  • Patent number: 6781016
    Abstract: A high-purity alicyclic ketone which is a raw material for an alkyl-substituted alicyclic ester such as an alkyl adamantyl ester compound which is useful as a resist raw material can be obtained by a simple operation such as extraction without a special purification step such as distillation or recrystallization. In this process, when an alicyclic hydrocarbon is oxidized with concentrated sulfuric acid or fuming sulfuric acid, the reaction solution after oxidation is poured into water and a solid is extracted with an organic solvent, the concentration of sulfuric acid in the water layer at the time of extraction is adjusted to 60 to 90 wt % to carry out extraction so as to obtain an alicyclic ketone.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: August 24, 2004
    Assignee: Tokuyama Corporation
    Inventors: Masao Yamaguchi, Hiromasa Yamamoto, Hideki Kikuchi, Yoshihiro Hirota, Atsushi Kadokura, Takashi Matsumura
  • Publication number: 20040077898
    Abstract: There is provided a method for obtaining a high-purity alkyladamantyl ester from an alkyladamantyl ester composition containing a large quantity of alkyladamantyl halide obtained by, for example, alkylating raw material 2-adamantanone obtained through oxidation of adamantane by use of an organic metal reagent and then causing an acid halide to react with the resulting product, efficiently by a simple process.
    Type: Application
    Filed: July 25, 2003
    Publication date: April 22, 2004
    Inventors: Masao Yamaguchi, Hiromasa Yamamoto, Hideki Kikuchi, Yoshihiro Hirota
  • Patent number: 6696595
    Abstract: There is provided a method for obtaining an alkyladamantyl ester efficiently by distilling and purifying a crude alkyladamantyl ester containing impurities which decompose the alkyladamantyl ester without decomposing the alkyladamantyl ester. The crude alkyladamantyl ester such as crude 2-methyl-2-adamantyl methacrylate is distilled in the presence of a heterocyclic compound and/or a basic compound such as 3-ethyl-3-hydroxymethyloxetane or diglycidyl bisphenol A.
    Type: Grant
    Filed: November 22, 2002
    Date of Patent: February 24, 2004
    Assignee: Tokuyama Corporation
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Yoshihiro Hirota, Takashi Kobayakawa
  • Publication number: 20040015008
    Abstract: The present invention discloses an adamantyl ester monomer composition characterized by containing at least an adamantyl ester monomer having at least one polymerizable unsaturated bond in the molecule, and a compound represented by the following general formula (1): 1
    Type: Application
    Filed: February 3, 2003
    Publication date: January 22, 2004
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Yoshihito Hirota
  • Patent number: 6635683
    Abstract: A memberane sensitive to anions is obtained by forming into a membrane either a composition comprising an onium salt compound such as trioctylmethylammonium chloride or tetraoctylammonium bromide, and an aromatic boric diester compound such as (p-alkyloxy)phenyl borate, or a composition which comprises these two ingredients and a membrane-forming polymer such as polyvinyl chloride or polystyrene, and may further contain a fat-soluble anion salt such as tetraphenyl borate. This membrane can yield an ion-selective electrode which permits hydrogencarbonate ions contained in body fluids to be rapidly determined with high sensitivity and high selectivity and which has a long life.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: October 21, 2003
    Assignee: Tokuyama Corporation
    Inventors: Hiroaki Taira, Kazuya Ibaragi, Hiromasa Yamamoto, Hiroyuki Yanagi
  • Publication number: 20030158437
    Abstract: A magnesium halide salt of a 2-alkyl-2-adamantanol is reacted with a carboxylic acid halide such as acrylic chloride or the like in the presence of a tertiary amine to produce a 2-alkyl-2-adamantyl ester (the first invention).
    Type: Application
    Filed: January 27, 2003
    Publication date: August 21, 2003
    Inventors: Masao Yamaguchi, Yoshihiro Hirota, Hiromasa Yamamoto
  • Publication number: 20030135068
    Abstract: There is provided a method for obtaining a target organic compound such as an alkyladamantyl ester efficiently by purifying a crude organic compound which contains, as impurities, sublimable materials which start to sublime at temperatures lower than a boiling point of the target organic compound by use of such a simple method as distillation during its production process, without being adversely affected by adherence of the sublimable materials.
    Type: Application
    Filed: November 22, 2002
    Publication date: July 17, 2003
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Hideki Kikuchi
  • Publication number: 20030120107
    Abstract: There is provided a method for obtaining an alkyladamantyl ester efficiently by distilling and purifying a crude alkyladamantyl ester containing impurities which decompose the alkyladamantyl ester without decomposing the alkyladamantyl ester.
    Type: Application
    Filed: November 22, 2002
    Publication date: June 26, 2003
    Inventors: Hiromasa Yamamoto, Masao Yamaguchi, Yoshihiro Hirota, Takashi Kobayakawa
  • Publication number: 20030109747
    Abstract: A high-purity alicyclic ketone which is a raw material for an alkyl-substituted alicyclic ester such as an alkyl adamantyl ester compound which is useful as a resist raw material can be obtained by a simple operation such as extraction without a special purification step such as distillation or recrystallization. In this process, when an alicyclic hydrocarbon is oxidized with concentrated sulfuric acid or fuming sulfuric acid, the reaction solution after oxidation is poured into water and a solid is extracted with an organic solvent, the concentration of sulfuric acid in the water layer at the time of extraction is adjusted to 60 to 90 wt % to carry out extraction so as to obtain an alicyclic ketone.
    Type: Application
    Filed: October 28, 2002
    Publication date: June 12, 2003
    Inventors: Masao Yamaguchi, Hiromasa Yamamoto, Hideki Kikuchi, Yoshihiro Hirota, Atsushi Kadokura, Takashi Matsumura
  • Publication number: 20030052765
    Abstract: An inductance component comprising a column-shaped magnetic material substrate 21, conductor layer 24 covering ends and a peripheral surface of the substrate, coil portion 27 having groove portion 25 and wire conductor portion 26 formed in the conductor layer covering the peripheral surface, electrode portions 28 including the conductor layer covering the ends of the substrate, and magnetic material portion 31 made of sintered magnetic material on the coil portion, wherein the conductor layer has a melting point higher than a sintering temperature of the sintered magnetic material. The manufacturing process comprises; forming a substrate, forming a conductor layer, forming a coil portion, forming electrode portions at ends of the substrate, and forming a magnetic material portion of sintered magnetic material on the coil portion. The present invention provides an inductance component with high inductance, low magnetic flux leakage, and less bad magnetic effects to adjacent components.
    Type: Application
    Filed: August 1, 2002
    Publication date: March 20, 2003
    Inventors: Toyonori Kanetaka, Toshihiro Yoshizawa, Hiromasa Yamamoto
  • Patent number: 6528003
    Abstract: A core sphere or a wound-string core is held by a pair of bottom rollers and a pair of concave top rollers. Then, the bottom rollers are reciprocated in opposite directions respectively and rotated to rotate the core sphere or the wound-string core and wind rubber string, and a wound-string core of a predetermined diameter is obtained by pressurizing the core sphere or the wound-string core intermittently by the pair of top rollers with a predetermined pressure. Rotation frequency of the bottom roller is set to be 1100 rpm to 200 rpm, ratio of the rotation frequency of the bottom roller to number of the horizontal movement of the bottom roller is set to be 10:15 to 15:10, and ratio of pressurizing number of the top rollers to the number of the horizontal movement of the bottom roller is set to be 1:14 to 1:5.
    Type: Grant
    Filed: January 14, 2000
    Date of Patent: March 4, 2003
    Assignee: Sumitomo Rubber Industries, Ltd.
    Inventors: Hideki Sano, Takayuki Saimen, Hiromasa Yamamoto, Hiroaki Tanaka
  • Publication number: 20020151114
    Abstract: Manufacturing method of the present invention comprises the steps of a conductive layer forming process for forming conductive layer 4 on outer periphery 2 and end surfaces 3 of substrate 1, a coil portion forming process for forming coil portion 7 having conductor 5 and groove 6 by cutting spirally the conductive layer 4, an etching process for etching the substrate 1 having the coil portion 7 formed thereon; an insulation resin coating process for forming outer coating 8 by coating a surface of the conductive layer 4 with insulation resin 13; and an electrode forming process for forming electrodes 9 at both ends of the coil portion 7, and for making electric contacts between electrodes 9 and the conductive layer 4. A chip inductor having a flattened mounting surface of the outer coating is obtained when insulation resin layer 8 is formed by an electrodeposition in the insulation resin coating process. The chip inductor can be securely mounted to a circuit board.
    Type: Application
    Filed: April 30, 2002
    Publication date: October 17, 2002
    Inventors: Toyonori Kanetaka, Toshihiro Yoshizawa, Akira Fujimori, Hideaki Nakayama, Hiromasa Yamamoto, Mikio Taoka, Kenichi Yamada
  • Patent number: 5728011
    Abstract: Disclosed is a thread wound golf ball comprising a center, a thread rubber layer formed by winding a thread rubber around the center and a cover formed on the thread rubber layer, wherein the thread rubber is obtained by cutting, into a suitable width, a rubber sheet for thread rubber which is obtained by vulcanizing a raw rubber sheet for thread rubber using a pressure rotary drum type continuous vulcanizing device.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: March 17, 1998
    Assignee: Sumitomo Rubber Industries, Ltd.
    Inventors: Kazushige Sugimoto, Hiromasa Yamamoto, Tsutomu Nosaka
  • Patent number: 5294817
    Abstract: In an output circuit for a charge transfer device, a floating diffusion region is connected to a source side gate electrode of a double-gate read-out field effect transistor having its drain side gate electrode connected to the drain of the read-out transistor itself. Thus, the capacitance between the gate of the read-out transistor connected to the floating diffusion region and the drain of the read-out transistor can be made small, so that the total capacitance of the floating diffusion region is correspondingly reduced, with the result that a high detection sensitivity can be realized.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: March 15, 1994
    Assignee: NEC Corporation
    Inventor: Hiromasa Yamamoto
  • Patent number: 5219632
    Abstract: According to the present invention, an ingot of the compound semiconductor single crystal grown by the LEC method or the HB method, or a block/blocks or wafers cut from the ingot is subjected to a high temperature annealing at any temperature in the range not less than 1100.degree. C. and not more than the melting point, and then the ingot is cooled at the cooling rate of 15.degree..about.30.degree. C./min. This method ensures that the egg-shape etch pit density revealed in the single crystal by AB etchant is 5.times.10.sup.4 cm.sup.-2 or less, preferably 5.times.10.sup.3 cm.sup.-2 or less. As a result, the device employing the single crystal as its substrate can be possessed of homogeneous property.
    Type: Grant
    Filed: October 20, 1989
    Date of Patent: June 15, 1993
    Inventors: Haruhito Shimakura, Gaku Kano, Hiromasa Yamamoto, Osamu Oda
  • Patent number: 5047370
    Abstract: A method for producing compound semiconductor single crystal substrates which comprises the following steps, wafers of a compound semiconductor single crystal grown by the LEC method are installed in an evacuated and sealed quartz ampoule and subjected to a first annealing step at the predetermined temperature for the predetermined period, then the wafers are gradually cooled down to room temperature at the predetermined cooling speed, the cooled wafers are then subjected to etching, the etched wafers are subjected to a second annealing step at the predetermined temperature for the predetermined period in a non-oxidizing atmosphere, and finally, the wafers are gradually cooled down to room temperature.
    Type: Grant
    Filed: July 3, 1990
    Date of Patent: September 10, 1991
    Assignee: Nippon Mining Co., Ltd.
    Inventors: Hiromasa Yamamoto, Masayuki Mori, Osamu Oda
  • Patent number: 4755784
    Abstract: A leadless chip inductor having metallic terminal plates and a coil element fixed to the metallic terminal plates, the metallic terminal plates being partially enclosed, together with the coil element, by a resin molded cover, the portions of the metallic terminal plates exposed to the outside of the molded outer cover being bent along the edge of the molded cover so as to form terminals for connection to an external circuit. The mechanical and electrical connection between the metallic terminal plates and the lead lines led from the coil is achieved by brazing or welding the lead lines to the undersides of a narrow strip-shaped tabs which is projected from each metallic terminal plate. With this arrangement, the coil lead lines are securely connected to the metallic terminal plates.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: July 5, 1988
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mikio Taoka, Hiromasa Yamamoto, Hiroshi Otake, Hironori Arima
  • Patent number: 4696100
    Abstract: A method of manufacturing a chip coil, including a coil element which includes a magnetic core, a winding wire, and internal terminal electrodes, a fired mass of magnetic material surrounding and encapsulating the coil element, and external terminal electrodes electrically connected to the internal terminal electrodes. The winding wire is coated with a heat-resistive electrically insulating film and is wound around the magnetic core. The internal terminal electrodes are electrically connected to opposite ends of the winding wire and are exposed to the exterior of the mass at opposite ends of the core where they are electrically connected to the external terminal electrodes.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: September 29, 1987
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiromasa Yamamoto, Sankichi Shida, Tsunehiko Todoroki