Patents by Inventor Ryuichi Ishikawa

Ryuichi Ishikawa 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: 5833813
    Abstract: A method of recovering ethylene sulfide from a hydrous stock solution (solution) containing ethylene sulfide, toluene (hydrophobic organic compound) having a higher boiling point than ethylene sulfide, and a compound having a higher boiling point than toluene, by distilling the stock solution continuously using a continuous fractionating tower 2, a fractionating tower 4, and a rectifying tower 5. Ethylene sulfide is distilled out with toluene and water from the continuous fractionating tower 2, and the distillate is allowed to separate into an oil layer and a water layer in a separating tank 3. The oil layer is distilled continuously by the fractionating tower 4 without being subjected to a reflux operation to distill out water with a part of ethylene sulfide. The bottom product from the fractionating tower 4 is rectified by the rectifying tower 5 to recover ethylene sulfide.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: November 10, 1998
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hitoshi Yano, Yoshinari Yamaguchi, Hirokazu Ito, Ryuichi Ishikawa, Yukihiro Matsumoto, Teruhisa Kaziwara
  • Patent number: 5821382
    Abstract: In order to manufacture a thiol compound by causing reaction between an unsaturated compound and hydrogen sulfide, the unsaturated compound and the thiol compound being expressed by following formulas (1) and (2), respectively:CH.sub.2 .dbd.CR.sup.1 --COOR.sup.2 (1)HS--CH.sub.2 --CHR.sup.1 --COOR.sup.2 (2)where R.sup.1 represents a hydrogen atom or a methyl group, and R.sup.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: October 13, 1998
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Youichi Hino, Ryuichi Ishikawa, Norihiro Wakao
  • Patent number: 5763620
    Abstract: A process for producing an alkylene sulfide, which comprises the step of subjecting a mercaptoalkanol to an intramolecular dehydration reaction in the presence of an acidic dehydration catalyst, to produce the alkylene sulfide, in which the intramolecular dehydration reaction is conducted under at least one conditions of (1) to (3). (1) The intramolecular dehydration reaction is conducted in at least one solvent selected from the group consisting of compounds having an amide group N-substituted with a hydrocarbon group having from 1 to 6 carbon atoms, compounds having an unsubstituted amide group, compounds having a ureylene group N-substituted with a hydrocarbon group having from 1 to 6 carbon atoms, and compounds having an unsubstituted ureylene group. (2) The intramolecular dehydration reaction is conducted in a solvent under such temperature and pressure conditions that the reaction temperature T (.degree.C.) and the boiling point tb (.degree.C.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: June 9, 1998
    Inventors: Youichi Hino, Yoshitaka Arita, Norihiro Wakao, Ryuichi Ishikawa
  • Patent number: 5478912
    Abstract: A process for producing a modified polyaminoamide with markedly increased reactivity as an epoxy resin curing agent is disclosed. The process comprises introducing amino groups and mercapto groups into a polyaminoamide by using an aziridine compound and a thiirane compound. The modified polyaminoamide is capable of curing an epoxy resin at a low temperature and at a high rate to provide a cured epoxy resin excellent in anticorrosion and chemical resistance.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: December 26, 1995
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazumasa Kimura, Takashi Kai, Hitoshi Yano, Ryuichi Ishikawa, Kazuaki Abe, Yoshihiro Arita
  • Patent number: 5304656
    Abstract: In a process for preparing alkylene sulfides through the intramolecular dehydration reaction of mercaptoalkanols in a gaseous phase, catalysts are used, which are represented by the formula: M.sub.a X.sub.b Y.sub.c O.sub.d, where M represents at least one element selected from the group of alkali metals, alkaline earth metals and thallium; X represents at least one element selected from the group of Al, B, Si and P; Y represents at least one element selected from the group consisting of lanthanides, IIIA group, IVA group, VA group, IIIB group, IVB group, VB group and VIB group, excluding an element contained in M or X; O represents oxygen; and a and b are numerical values not equal to 0; b=0.2-100 and c=0-50 when a=1; and d is a numerical value determined according to a, b and c.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: April 19, 1994
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hitoshi Yano, Yoshinari Yamaguchi, Kimio Ariyoshi, Yuuji Shimasaki, Ryuichi Ishikawa, Michio Ueshima
  • Patent number: 5288299
    Abstract: A compact exhaust gas treating apparatus which is improved in the bag filter performance in order to reduce the amount of dioxin contained in exhaust gas discharged from municipal refuse incineration equipment, industrial waste incineration equipment, etc. An activated carbon filter is disposed along the filter cloth of the bag filter at the purified gas outlet side of the filter cloth so that exhaust gas passes through the activated carbon filter after passing through the filter cloth, thereby being purified.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: February 22, 1994
    Assignee: Ebara Corporation
    Inventors: Hiroshi Yoshida, Mitsuyoshi Kaneko, Ryuichi Ishikawa
  • Patent number: 5127345
    Abstract: A combustion apparatus has a combustion furnace section, a free board section which is downstream of the combustion furnace section, and a post-combustion chamber which is downstream of the free board section, the post-combustion chamber being disposed at a position offset from the position directly above the free board section, wherein the apparatus is characterized in that a gas blowing structure is provided in the vicinity of the boundary between the free board section and the post-combustion chamber, the gas blowing structure having a plurality of pipes disposed parallel to each other at a predetermined spacing, each pipe being provided with a gas outlet hole for blowing a gas, for example, air, counter to the combustion gas flowing toward a discharge port.
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: July 7, 1992
    Assignee: Ebara Corporation
    Inventors: Ryuichi Ishikawa, Takahiro Ohshita, Chikao Goke, Kiyoshi Asai
  • Patent number: 5107757
    Abstract: A method of and apparatus for dewatering a substance which is to be dewatered such as sludge wherein the substance to be dewatered is pressed between a pair of rollers (11, 212) or plate-shaped press members (331) each having its press surface formed from a rigid porous material (6, C, 331) having water absorption and retention properties based on the capillary action; water squeezed from the substance by pressing is permeated into the rigid porous material due to water absorption based on the capillary action or water pressure and the permeated water is retained by virtue of the water retention properties based on the capillary action, thereby dewatering the substance; and the water retained by the rigid porous material is discharged by sending pressurized air to regenerate the capillary tubes.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: April 28, 1992
    Assignees: Ebara Corporation, Ibiden Co., Ltd.
    Inventors: Takahiro Ohshita, Ryuichi Ishikawa, Tetsuhisa Hirose, Kiyoshi Asai
  • Patent number: 4324759
    Abstract: There is disclosed an apparatus for treating waste gas containing nitrogen oxides and sulfur dioxide by irradiation with electron beams with the addition of ammonia, which apparatus comprises a reactor having an inlet and an outlet for the waste gas and a window through which electron beams pass to irradiate the waste gas inside the reactor, an electron beam accelerator as a source of said electron beams and a dust collector which receives the irradiated waste gas and removes solid particles therefrom, characterized in that said apparatus further comprises two independently operating automatic controlling systems and a judging system; the first controlling system operates under normal conditions; the second controlling system operates only in the case of emergency when the judging system has detected abnormal changes with respect to the concentrations of NO.sub.x, SO.sub.2 and NH.sub.3 of the waste gas.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: April 13, 1982
    Assignees: Ebara Corp, Japan Iron and Steel Federation
    Inventors: Shinji Aoki, Ryuichi Ishikawa, Yasuhiro Sawada