Patents by Inventor Hirofumi Higuchi

Hirofumi Higuchi 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: 6121939
    Abstract: When a converter 14 is rotated via a rotation mechanism 17, the arrangement inclination angle of two primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. with respect to an axis which is in parallel with the ground. Also the reception polarization angle due to probes of the primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. while maintaining a preset difference in polarization angle among the satellites. Therefore, the arrangement inclination angle of the primary radiators 15a and 15b for respectively receiving signals from the two satellites, and the reception polarization angle in the primary radiators 15a and 15b can be simultaneously easily adjusted by rotating the converter 14 via the rotation mechanism 17.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: September 19, 2000
    Assignee: Yagi Antenna Co., Ltd.
    Inventors: Hiroaki Imaizumi, Koji Sakauchi, Shuji Hagiwara, Hirofumi Higuchi, Ryotaro Manabe
  • Patent number: 6114143
    Abstract: A monoclonal antibody useful for clinical application which recognizes the conserved region of V3-PND region of glycoprotein antigen having a molecular weight of about 1.2.times.10.sup.5 daltons (gp120) on a coating membrane of human immunodeficiency virus (HIV) and which has an ability to neutralize a broad range of various HIV variants, or a fragment thereof, and the chimeric and humanized antibodies derived therefrom are provided. By using as an immunogen a plurality of peptides having PND-Tip region containing the highly conserved GPGR sequence within PND of HIV gp120, a monoclonal antibody having a neutralizing activity to many HIV variants can be prepared. By transplanting the gene fragment coding for the variable region of said monoclonal antibody or complementarity determining region (CDR) of said region to a human antibody gene, a chimeric antibody or a reshaped antibody having an anti-HIV neutralizing activity which are effective for clinical application can be obtained.
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: September 5, 2000
    Assignee: Juridical Foundation The Chemo-Sero-Therapeutic Research Institute
    Inventors: Yasuyuki Eda, Hiroaki Maeda, Keiichi Makizumi, Kouichi Shiosaki, Kiyoshi Osatomi, Kazuhiko Kimachi, Hirofumi Higuchi, Sachio Tokiyoshi
  • Patent number: 6052099
    Abstract: When a converter 14 is rotated via a rotation mechanism 17, the arrangement inclination angle of two primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. with respect to an axis which is in parallel with the ground. Also the reception polarization angle due to probes of the primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. while maintaining a preset difference in polarization angle among the satellites. Therefore, the arrangement inclination angle of the primary radiators 15a and 15b for respectively receiving signals from the two satellites, and the reception polarization angle in the primary radiators 15a and 15b can be simultaneously easily adjusted by rotating the converter 14 via the rotation mechanism 17.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: April 18, 2000
    Assignee: Yagi Antenna Co., Ltd.
    Inventors: Hiroaki Imaizumi, Koji Sakauchi, Shuji Hagiwara, Hirofumi Higuchi, Ryotaro Manabe
  • Patent number: 5824818
    Abstract: A process for preparing a lactate which includes: (a) preparing lactonitrile from prussic acid and acetaldehyde, (b) hydrating the lactonitrile to form lactamide, (c) forming the desired lactate and formamide from lactamide and formate (or methanol and carbon monoxide), (d) separating and collecting components, having a lower boiling point than that of lactate from the reaction liquid in step (c), by distillation under specified conditions, and (e) dehydrating formamide from step (d) to form prussic acid and recycling the prussic acid to step (a). Heretofore, lactates had been manufactured by forming lactonitrile (cyanohydrin) from acetaldehyde and prussic acid, and then esterifying lactonitrile with a mineral acid or the like. However, in this conventional process, ammonium salts were formed as by-products in an amount equal to that of the lactate.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: October 20, 1998
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Takafumi Abe, Toshiyuki Gotoh, Takako Uchiyama, Hirofumi Higuchi, Yoshikazu Shima, Kazuto Ikemoto
  • Patent number: 5703272
    Abstract: A process for preparing a carboxylic acid ester which includes subjecting a carboxylic acid and an alcohol or a phenol to an esterification reaction in the presence of a silica-titania catalyst. The silica-titania catalyst is prepared by adding an acidic solution containing a silicon compound and a titanium compound dissolved therein to a solution of a basic compound to bring about co-precipitation, in which the acidic solution is a nitric acid-acidic solution or a sulfuric acid-acidic solution, a ratio of the amount (gram equivalent) of nitric acid or sulfuric acid to the amount (mol) of the silicon compound in the acidic solution is 0.5 to 50 and the amount of the titanium compound in the acidic solution is such that a ratio of titania (TiO.sub.2) in the silica-titania catalyst is 1 to 50% by weight.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: December 30, 1997
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Mariko Abe, Shuji Ebata, Takafumi Abe, Hirofumi Higuchi
  • Patent number: 5587349
    Abstract: A process for preparing a silica-titania catalyst by adding an acidic solution containing a silicon compound such as sodium silicate and a titanium compound such as titanium sulfate dissolved therein to a solution of a compound such as ammonium bicarbonate to bring about co-precipitation, in which the acidic solution is a highly concentrated nitric acid-acidic or sulfuric acid-acidic solution, and a ratio of the dissolved titanium compound in the acidic solution is regulated in a certain range.According to this process, a catalyst capable of exerting a high performance in an esterification reaction and the like can be efficiently obtained.
    Type: Grant
    Filed: December 30, 1994
    Date of Patent: December 24, 1996
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Mariko Abe, Shuji Ebata, Takafumi Abe, Hirofumi Higuchi
  • Patent number: 5463123
    Abstract: There is disclosed a process for producing .alpha.-hydroxyisobutyramide by hydration reaction of acetone cyanohydrin in the presence of a catalyst consisting essentially of manganese dioxide which process comprises pretreating the catalyst with a reducing agent. The above process is capable of eliminating the catalyst clogging trouble due to the deposition of the by-produced oxamide and thus proceeding with long-term reaction with the stabilized catalyst performance.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: October 31, 1995
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Takako Uchiyama, Hirofumi Higuchi
  • Patent number: 5439661
    Abstract: There is disclosed a process for efficiently producing hydrogen cyanide at a reaction temperature of preferably 250.degree. to 550.degree. C. by a catalytic dehydrative reaction of formamide which comprises employing as a catalyst, a manganese oxide (MnO) and/or a magnesium oxide (MgO) each modified with an alkali metal (Na, K, Rb, Cs, etc. ). The above process is capable of producing hydrogen cyanide at an enhanced conversion efficiency of formamide and at a high selectivity while minimizing the by-production of ammonia. The use of the catalyst comprising as a principal component, MnO modified with an alkali metal is particularly effective in prolonging its service life and enables a long-term stable operation.
    Type: Grant
    Filed: October 27, 1994
    Date of Patent: August 8, 1995
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Takafumi Abe, Shuji Ebata, Kazuhiro Sugamura, Taiji Matsuzaki, Hirofumi Higuchi
  • Patent number: 5434620
    Abstract: An image sensor can reduce fixed pattern noise (FPN) caused by transistors used for reading pixel signals. The image sensor comprises photodiodes D.sub.1, D.sub.2, . . . connected to a precharge line L.sub.PR through respective precharge transistors (Tr1).sub.1, (Tr1).sub.2 ; and pixel amplification transistors (Tr2).sub.1, (Tr2).sub.2, . . . , one end thereof being connected to a signal read line L.sub.RE, the other end thereof being grounded through respective pixel switching transistors (Tr3).sub.1, (Tr3).sub.2, . . . , and the gates thereof being connected to respective nodes between the precharge transistors Tr1, (Tr1).sub.2, . . . and the photodiodes D.sub.1, D.sub.2, . . . According to signals provided by a timing signal generator 3, the pixel switching transistors (Tr3).sub.1, (Tr3).sub.2, . . . are sequentially turned ON and OFF one after another.
    Type: Grant
    Filed: September 28, 1993
    Date of Patent: July 18, 1995
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hirofumi Higuchi, Yasuaki Makino
  • Patent number: 5391813
    Abstract: There is disclosed a process for efficiently producing methyl .alpha.-hydroxyisobutyrate from .alpha.-hydroxyisobutyramide and methyl formate by means of reaction distillation which comprises feeding .alpha.-hydroxyisobutyramide and an alkali metal hydroxide in a continuous distillation column to prepare therein the dehydrated condensate of .alpha.-hydroxyisobutyramide with the alkali metal hydroxide as the catalyst and reacting remaining .alpha.-hydroxyisobutyramide with methyl formate in the presence of the dehydrated condensate as the catalyst.According to the above process, the objective methyl .alpha.-hydroxyisobutyrate is continuously obtained in high yield and high selectivity without any operational trouble.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: February 21, 1995
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Nobuyuki Muro, Takafumi Abe, Hirofumi Higuchi
  • Patent number: 5371273
    Abstract: There is disclosed a process for producing methyl methacrylate through gas-phase catalytic reaction of methyl .alpha.-hydroxyisobutyrate which comprises feeding methanol in an amount by weight of 0.1 to 3.0 times the methyl .alpha.-hydroxyisobutyrate in a reactor along therewith and proceeding with the reaction at a reaction temperature in the range of 230.degree. to 300.degree. C. by the use of a transition-type synthetic faujasite zeolite having a specific lattice constant and a specific Na content (Na/Al) as the catalyst. The process is capable of stably producing the objective product having excellent quality in high yield for a long period of time while preventing the problems of early deterioration of the catalyst and coloring of reaction product.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: December 6, 1994
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Yoshikazu Shima, Takafumi Abe, Hirofumi Higuchi
  • Patent number: 5312966
    Abstract: There is disclosed a process for efficiently producing a carboxylic acid ester and formamide by reacting a carboxylic acid amide with a formic acid ester or with an alcohol and carbon monoxide in the presence of a strongly basic anion-exchange resin. By the use of the strongly basic anion-exchange resin as the catalyst, the process of the present invention enables the efficient production of the carboxylic acid ester as well as formamide from the Carboxylic acid amide and Formic acid ester, etc. with a high selectivity under mild reaction conditions and facilitates the separation of the catalyst from the reaction product, thereby greatly enhancing the industrial significance of itself.
    Type: Grant
    Filed: September 14, 1992
    Date of Patent: May 17, 1994
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Takafumi Abe, Yoshiyuki Nishide, Nobuyuki Muro, Hirofumi Higuchi
  • Patent number: 5225594
    Abstract: A process for producing methacrylic acid which comprises: (I) producing acetonecyanohydrin from prussic acid and acetone; (II) hydrating the acetonecyanohydrin obtained in step (I) to form .alpha.-hydroxyisobutyric acid amide; (III) reacting the .alpha.-hydroxyisobutyric acid amide obtained in step (II) with methyl formate or with methanol and carbon monoxide to form methyl .alpha.-hydroxyisobutyrate and formamide; (IV) hydrolyzing the methyl .alpha.-hydroxyisobutyrate obtained in step (III) to form .alpha.-hydroxyisobutyric acid; (V) dehydrating the .alpha.-hydroxyisobutyric acid obtained in step (IV) to form methacrylic acid; and (VI) dehydrating the formamide separated from the products obtained in step (III) to form prussic acid and recycling the prussic acid to step (I) as a starting material. The process is capable of producing methacrylic acid from readily available starting materials with a high yield and selectivity, without forming undesirable by-product or waste materials, such as ammonium sulfate.
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: July 6, 1993
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Yoshikazu Shima, Takafumi Abe, Hirofumi Higuchi
  • Patent number: 5194668
    Abstract: Carboxylic acid esters and formamide are efficiently obtained by reacting carboxylic acid amides and formic acid esters, or by reacting carboxylic acid amides, alcohols and carbon monoxide in the presence of a dehydrated condensate of carboxylic acid amide with an alkali metal hydroxide or an alkaline earth metal hydroxide catalyst.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: March 16, 1993
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Hideo Ikarashi, Hirofumi Higuchi, Koichi Kida
  • Patent number: 5175366
    Abstract: A process for preparing an amide by hydrating a cyanohydrin with a denatured manganese dioxide catalyst. The catalyst is prepared by reacting an aqueous permanganate solution and an aqueous manganese (II) compound solution in an acidic aqueous solution at a temperature of 70.degree. C. to 150.degree. C.
    Type: Grant
    Filed: August 14, 1991
    Date of Patent: December 29, 1992
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Shuji Ebata, Hiroyuki Hirayama, Hirofumi Higuchi, Koichi Kida
  • Patent number: 5087737
    Abstract: Disclosed is a process for producing methyl methacrylate which comprises:(I) a step of reacting prussic acid and acetone to form acetonecyanhydrin;(II) a step of hydrating the acetonecyanhydrin obtained in the step (I) to form .alpha.-hydroxyisobutyric acid amide;(III) a step of dehydrating the .alpha.-hydroxyisobutyric acid amide obtained in the step (II) to form methacrylic acid amide;(IV) a step of reacting the methacrylic acid amide obtained in the step (III) and methyl formate to form methyl methacrylate and formamide; and(V) a step of dehydrating formamide separated from the product obtained in the step (IV) to form prussic acid and recycling said prussic acid as a starting material in the step (I).The process produces methyl methacrylate with high selectivity without undesirable by-product such as ammonium sulfate.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: February 11, 1992
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Hirofumi Higuchi, Koichi Kida, Shuji Ebata
  • Patent number: 5087750
    Abstract: A process for producing .alpha.-hydroisobutyric acid amide by a hydration reaction of acetonecyanohydrin in the presence of a catalyst containing manganese dioxide as a main component, and also in the presence of an oxidizing agent. In accordance with the process, the service life of the catalyst is increased, and the .alpha.-hydroxyisobutyric acid amide is produced in a high yield.
    Type: Grant
    Filed: September 24, 1990
    Date of Patent: February 11, 1992
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Akitomo Uda, Shuji Ebata, Hirofumi Higuchi
  • Patent number: 5087736
    Abstract: Disclosed is a process for producing methyl methacrylate which comprises:(I) a step of reacting acetone and prussic acid to form acetonecyanhydrin;(II) a step of hydrating the acetonecyanhydrin obtained in the step (I) to form .alpha.-hydroxyisobutyric acid amide;(III) a step of reacting the .alpha.-hydroxyisobutyric acid amide obtained in the step (II) which methyl formate to form methyl .alpha.-hydroxyisobutyrate and formamide;(IV) a step of dehydrating the methyl .alpha.-hydroxyisobutyrate obtained in the step (III) to form methyl methancrylate; and(V) a step of decomposing the formamide obtained in the step (IV) into ammonia and carbon monoxide.The process can produce methyl methacrylate at high yields without by-production of acidic ammonium sulfate.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: February 11, 1992
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Hirofumi Higuchi, Koichi Kida
  • Patent number: 5075493
    Abstract: A process for producing .alpha., .beta.-unsaturated carboxylic acid ester which comprises catalytically reacting .alpha.-hydroxycarboxylic acid ester with crystalline aluminosilicate catalyst, and then catalytic reacting the resulting reaction product with solid acid catalyst.According to the process, .alpha., .beta.-unsaturated carboxylic acid ester of a high purity, and a high quality, without by-product, can be produced efficiently.
    Type: Grant
    Filed: November 23, 1990
    Date of Patent: December 24, 1991
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Yoshikazu Shima, Takafumi Abe, Hirofumi Higuchi, Koichi Kida
  • Patent number: 5061675
    Abstract: A process for producing a denatured manganese dioxide for the hydration reaction of cyanohydrins comprising reacting an aqueous permanganate salt solution and an aqueous manganese (II) compound in an acidic aqueous solution at a temperature of 70.degree. C. to 130.degree. C. is disclosed. The manganese dioxide catalyst obtained by the process exhibits a high activity over a long period in the preparation of an amide by the hydration of the corresponding cyanohydrin.
    Type: Grant
    Filed: June 25, 1990
    Date of Patent: October 29, 1991
    Assignee: Mitsubishi Gas Chemical Company, Inc.
    Inventors: Shuji Ebata, Hiroyuki Hirayama, Hirofumi Higuchi, Koichi Kida