Patents Assigned to Hidefumi Hirai
  • Patent number: 6051614
    Abstract: Disclosed is a method for preparing a non-aqueous dispersion of particles of a metal and/or a metal compound, which comprises contacting an aqueous dispersion of particles of a metal and/or a metal compound with a water-immiscible, non-aqueous liquid in the presence of a surfactant and in the presence or absence of a water-soluble inorganic acid salt and/or a water-soluble organic acid salt exhibiting substantially no surface activity, wherein when the contacting of the aqueous dispersion with the non-aqueous liquid is conducted in the absence of the salt, the salt is added after the contacting, thereby causing the particles to be migrated from the aqueous dispersion into the non-aqueous liquid.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: April 18, 2000
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Hyoya Shiozaki, Hotaka Aizawa
  • Patent number: 5319134
    Abstract: Disclosed is a process for introducing a carboxyl group to an aromatic carboxylic acid or a derivative thereof, which comprises reacting a starting aromatic carboxylic acid, such as a benzoic acid, a biphenylcarboxylic acid, a naphthalenecarboxylic acid, a diphenylcarboxylic acid, or a derivative thereof, with a carbon tetrahalide in the presence of a cyclodextrin and an alkali metal hydroxide, thereby introducing a carboxyl group to the aromatic ring of the starting aromatic carboxylic acid or the derivative thereof in substitution for a hydrogen atom bonded thereto. By the process of the present invention, a desired aromatic polycarboxylic acid or a derivative thereof can be easily obtained with high selectivity.
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: June 7, 1994
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Rikinori Terakado, Hisashi Mihori, Tsutomu Nakamura, Kazuhiro Saito
  • Patent number: 4902776
    Abstract: Poly-p-phenylene is produced by reaction of benzene with oxygen gas in the presence of a chloride of a metal having a lower valence and aluminum chloride.
    Type: Grant
    Filed: January 12, 1988
    Date of Patent: February 20, 1990
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Naoki Toshima, Keiichi Kanaka, Atsunori Koshirai
  • Patent number: 4888248
    Abstract: There is disclosed a novel colloidal metal dispersion in which colloidal particles of a metal are protected by specific polymers including hydrazide polymers, acrylic ester polymers and acrylamide polymers. The colloidal metal dispersion is highly stable, and the colloidal metal particles protected by such specific polymers can be easily and strongly bound to various amino group-containing compounds to give stable colloidal metal complexes, which have a wide variety of uses, such as the use as a solid catalyst, the use for the treatment and diagnosis of various diseases, the use for studying tissues of living bodies, the use for including mutation of microorganisms, etc.
    Type: Grant
    Filed: May 7, 1987
    Date of Patent: December 19, 1989
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Michitaka Otaki
  • Patent number: 4864071
    Abstract: A solid adsorbent for an unsaturated hydrocarbon comprising (a) (i) a silver or copper(I) halide or (ii) a silver or copper(I) halide and the halide of a bivalent metal, or (iii) a silver or copper(I) halide and an aluminum halide, and (b) polystyrene or a derivative thereof.This solid adsorbent can effectively adsorb an unsaturated hydrocarbon such as ethylene from a gas mixture by contacting the gas mixture therewith at a temperature of -40.degree. C. to 140.degree. C. under normal pressures.
    Type: Grant
    Filed: September 4, 1987
    Date of Patent: September 5, 1989
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Susumu Hara
  • Patent number: 4747855
    Abstract: A solid adsorbent for an unsaturated hydrocarbon including (a) (i) a copper(I) halide or oxide or (ii) a halide, carboxylate, sulfate, basic salt, oxide, or amine complex salt of copper(II) and (b) activated carbon or graphite is described.This solid adsorbent can effectively adsorb an unsaturated hydrocarbon such as ethylene from a gas mixture by being placed in contact with the gas mixture at a temperature of -40.degree. C. to 90.degree. C. under normal pressure.
    Type: Grant
    Filed: January 21, 1987
    Date of Patent: May 31, 1988
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Keiichiro Wada
  • Patent number: 4675309
    Abstract: There is disclosed an adsorbent comprising a macroreticular polystyrene type resin having amino groups selected from the group consisting of primary, secondary and tertiary amino groups and combinations thereof, and a copper(I) halide fixed to the macroreticular polystyrene type resin. Such an adsorbent has been found to be advantageously employed for the selective adsorption-separation of a gas from a gaseous mixture.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: June 23, 1987
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Kazunori Kurima, Keiichiro Wada
  • Patent number: 4587114
    Abstract: A solid form adsorbent of carbon monoxide, that is obtained by the process including the following steps. First, copper salts or copper oxide is stirred in a solvent. Then, into the solution or suspension thus obtained, active carbon is added. Finally, the solvent is removed by means of pressure reduction, distillation, etc. The carbon monoxide adsorbent produced according to this invention adsorbs carbon monoxide rapidly when it is brought into contact with a mixed gas. The adsorbed carbon monoxide can be readily separated and discharged through either heating the carbon monoxide adsorbent to above 60.degree. C. or reducing the partial pressure of carbon monoxide. The carbon monoxide obtained in accordance with the present invention is stable relative to the water content in the mixed gas, and it is capable of separating carbon monoxide directly from the mixed gas containing the water. Also, the separated carbon monoxide does not contain the vapor of the solvent from the carbon monoxide adsorbent.
    Type: Grant
    Filed: March 14, 1983
    Date of Patent: May 6, 1986
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Keiichiro Wada
  • Patent number: 4546094
    Abstract: A solid adsorbent for an unsaturated hydrocarbon comprising (a) (i) a silver or copper(I) halide or (ii) a silver or copper(I) halide and the halide of a bivalent metal, or (iii) a silver or copper(I) halide and an aluminum halide, and (b) polystyrene or a derivative thereof.This solid adsorbent can effectively adsorb an unsaturated hydrocarbon such as ethylene from a gas mixture by contacting the gas mixture therewith at a temperature of -40.degree. C. to 140.degree. C. under normal pressures.
    Type: Grant
    Filed: March 8, 1984
    Date of Patent: October 8, 1985
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Susumu Hara
  • Patent number: 4525180
    Abstract: With application of new liquid absorbent, comprised of a compound selected from a group composed of silver halide and cuprous halide, an aluminium halide, a polymer selected from a group composed of styrene and styrene derivatives, and an aromatic hydrocarbon, it is possible to recover ethylene by absorbing ethylene from gaseous mixture containing ethylene such as FCC off gas, ethylene plant off gas and coke oven gas. In particular, said liquid absorbent is neither diluted nor reduced its capability to absorb ethylene by water or its vapor contained in the said gaseous mixture, so the liquid absorbent can be used repeatedly for the recovery of ethylene from gaseous mixture containing ethylene and water or its vapor, without any pretreatment to reduce the water content of said gaseous mixture.
    Type: Grant
    Filed: March 15, 1984
    Date of Patent: June 25, 1985
    Assignee: Hidefumi Hirai
    Inventors: Hidefumi Hirai, Makoto Komiyama, Susumu Hara