Patents by Inventor Masahiro Tojo

Masahiro Tojo 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: 8148566
    Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: April 3, 2012
    Assignee: Asahi Kasei Chemicals Corporation
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Patent number: 7919644
    Abstract: A process for producing an aromatic carbonate, which comprises the steps of: (I) transesterifying a starting material selected from the group consisting of a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof with a reactant selected from the group consisting of an aromatic monohydroxy compound, an alkyl aryl carbonate and a mixture thereof, in the presence of a catalyst, to thereby obtain a high boiling point reaction mixture comprising an aromatic carbonate (a) and an aromatic carbonate ether (b), while withdrawing a low boiling point reaction mixture containing a low boiling point by-product; and (II) separating the aromatic carbonate ether (b) from the high boiling point reaction mixture to thereby obtain a high purity aromatic carbonate.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: April 5, 2011
    Assignee: Asahi Kasei Chemicals Corporation
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Publication number: 20100076213
    Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.
    Type: Application
    Filed: November 25, 2009
    Publication date: March 25, 2010
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Patent number: 7645896
    Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: January 12, 2010
    Assignee: Asahi Kasei Chemicals Corporation
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Publication number: 20080242882
    Abstract: A method for producing a dialkyl carbonate and a diol, comprising: (a) effecting a transesterification reaction between a cyclic carbonate and an aliphatic monohydric alcohol in the presence of a transesterification catalyst, thereby obtaining a reaction mixture containing a product dialkyl carbonate and a product diol, (b) withdrawing a dialkyl carbonate-containing liquid from the reaction mixture, followed by separation of the dialkyl carbonate from the dialkyl carbonate-containing liquid, and (c) withdrawing a diol-containing liquid from the reaction mixture, followed by separation of the diol from the diol-containing liquid, wherein the cyclic carbonate contains a cyclic ether in an amount of from 0.1 to 3,000 ppm by weight, and the product dialkyl carbonate contains a carbonate ether of not more than 10,000 ppm by weight.
    Type: Application
    Filed: June 17, 2005
    Publication date: October 2, 2008
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Publication number: 20070185164
    Abstract: A process for producing an aromatic carbonate, which comprises the steps of: (I) transesterifying a starting material selected from the group consisting of a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof with a reactant selected from the group consisting of an aromatic monohydroxy compound, an alkyl aryl carbonate and a mixture thereof, in the presence of a catalyst, to thereby obtain a high boiling point reaction mixture comprising an aromatic carbonate (a) and an aromatic carbonate ether (b), while withdrawing a low boiling point reaction mixture containing a low boiling point by-product; and (II) separating the aromatic carbonate ether (b) from the high boiling point reaction mixture to thereby obtain a high purity aromatic carbonate.
    Type: Application
    Filed: June 17, 2005
    Publication date: August 9, 2007
    Inventors: Masahiro Tojo, Hironori Miyaji
  • Patent number: 6479689
    Abstract: A method for continuously producing a dialkyl carbonate and a diol, comprising: (1) continuously feeding a cyclic carbonate and an aliphatic monohydric alcohol to a continuous multi-stage distillation column, and continuously effecting a transesterification between the cyclic carbonate and the aliphatic monohydric alcohol in the presence of a transesterification catalyst in the distillation column, while continuously withdrawing a low boiling point mixture in a gaseous form containing the produced dialkyl carbonate and the unreacted aliphatic monohydric alcohol from an upper portion of the distillation column and continuously withdrawing a high boiling point mixture in a liquid form containing the produced diol and the unreacted cyclic carbonate from a lower portion of the distillation column, and (2) continuously feeding the high boiling point mixture withdrawn from the lower portion of the distillation column to a continuous etherification reactor, to thereby effect a continuous etherification reaction betw
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: November 12, 2002
    Assignee: Asahi Kasei Kabushiki Kaisha
    Inventors: Masahiro Tojo, Kazuhiro Oonishi
  • Patent number: 6472525
    Abstract: Disclosed is an acyl group-containing hexaazaisowurtzitane derivative represented by the following formula (I): W At Q(6−t), wherein t represents an integer of from 4 to 6, A independently represents an acyl group having 1 to 10 carbon atoms, each Q independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and W represents a hexavalent hexaazaisowurtzitane residue represented by the following formula (II): Also disclosed is a method for producing the above-mentioned acyl group-containing hexaazaisowurtzitane derivative. The acyl group-containing hexaazaisowurtzitane derivative of the present invention is useful as a precursor of a polynitrohexaazaisowurtzitane derivative which can be used not only as a material for explosives but also as an additive for propellants and explosives.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: October 29, 2002
    Assignee: Asahi Kasei Kabushiki Kaisha
    Inventors: Tamotsu Kodama, Masahiro Tojo, Masanori Ikeda
  • Patent number: 6346638
    Abstract: A method for continuously producing a (A) dialkyl carbonate and a (B) diol, comprising continuously feeding a cyclic carbonate and an aliphatic monohydric alcohol to a continuous multi-stage distillation column to thereby effect a transesterification therebetween, thereby continuously producing a dialkyl carbonate and a diol, while continuously withdrawing a low boiling point mixture containing the produced dialkyl carbonate (A) in a gaseous form from an upper portion of the distillation column and continuously withdrawing a high boiling point mixture containing the produced diol (B) in a liquid form from a lower portion of the distillation column, wherein the transesterification is performed under conditions wherein: (a) the reaction pressure of the column bottom is 5×104 Pa or less; (b) the reaction temperature of the column bottom is in the range of from −20° C. to less than 60° C.; and (c) the distillation column has an F-factor in the range of from 0.2 to 5.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: February 12, 2002
    Assignee: Asahi Kasel Kabushiki Kaisha
    Inventors: Masahiro Tojo, Kazuhiro Oonishi
  • Patent number: 6262210
    Abstract: A process for producing aromatic carbonates, which comprises transesterifying, in the presence of a metal-containing catalyst, a starting material selected from a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof with a reactant selected from an aromatic monohydroxy compound, an alkyl aryl carbonate and a mixture thereof, characterized in that: at least one type of catalyst-containing liquid is taken out, wherein the catalyst-containing liquid is selected from a portion of a high boiling point reaction mixture obtained by the above transesterification and containing the desired aromatic carbonate and the metal-containing catalyst, and a portion of a liquid catalyst fraction obtained by separating the desired aromatic carbonate from the high boiling point reaction mixture, wherein each portion contains (A) high boiling point substance having a boiling point higher than the boiling point of the produced aromatic carbonate and (B) the metal-containing catalyst; (C) a functional substance capable o
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: July 17, 2001
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Masahiro Tojo, Kazuhiro Oonishi, Kyosuke Komiya
  • Patent number: 5872275
    Abstract: Disclosed is a process for producing an aromatic carbonate which comprises transesterifying, in the presence of a metal-containing catalyst, a starting material selected from the group consisting of a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof with a reactant selected from the group consisting of an aromatic monohydroxy compound, an alkyl aryl carbonate and a mixture thereof, wherein the transesterification is conducted while maintaining a weight ratio (WR) of at least one aromatic group-containing substance selected from the group consisting of a specific aromatic polyhydroxy compound and a residue thereof to the metal of the metal-containing catalyst at 2.0 or less, wherein the weight ratio (WR) is measured with respect to a catalyst-containing liquid-phase mixture in a system for the transesterification, and wherein the aromatic group-containing substance originates from the starting material, the reactant and/or a by-product of the transesterification.
    Type: Grant
    Filed: September 24, 1997
    Date of Patent: February 16, 1999
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Kyosuke Komiya, Masahiro Tojo, Shinsuke Fukuoka
  • Patent number: 5847189
    Abstract: Disclosed is a method for continuously producing a dialkyl carbonate and a diol, comprising: (1) feeding a cyclic carbonate and an aliphatic monohydric alcohol to a continuous multi-stage distillation column, and effecting a transesterification in the presence of a catalyst in the multi-stage distillation column and/or at least one transesterification reactor which communicates fluid-tightly with the distillation column, while continuously withdrawing a low boiling point gaseous mixture containing the produced dialkyl carbonate from a upper portion of the distillation column and a high boiling point liquid mixture from a lower portion of the distillation column; and (2) continuously feeding water and the high boiling point mixture to a hydrolysis reactor, to thereby effect a continuous hydrolysis of the unreacted cyclic carbonate contained therein and produce a diol and carbon dioxide.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: December 8, 1998
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Masahiro Tojo, Shinsuke Fukuoka, Mamoru Kawamura
  • Patent number: 5210268
    Abstract: Disclosed is a process for producing an aromatic carbonate or aromatic carbonate mixture by a transesterification reaction between a starting material selected from a dialkyl carbonate, an alkyl aryl carbonate and a mixture thereof and a reactant selected from an aromatic hydroxy compound, an alkyl aryl carbonate and a mixture thereof, wherein the starting material and the reactant are continuously fed to a continuous multi-stage distillation column to effect a transesterification reaction therebetween in the presence of a catalyst in the distillation column, while continuously withdrawing the produced aromatic carbonate or aromatic carbonate mixture as a high boiling point product in a liquid form from a lower portion of the distillation column and continuously withdrawing the by-product as a low boiling point product in a gaseous form from an upper portion of the distillation column by distillation, thereby enabling the aromatic carbonate or aromatic carbonate mixture to be produced continuously.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: May 11, 1993
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Shinsuke Fukuoka, Masahiro Tojo, Mamoru Kawamura
  • Patent number: 5166393
    Abstract: A process for producing a diaryl carbonate in high yield and with high selectivity which comprises disproportionating an alkylaryl carbonate in the presence of a lead catalyst to produce a diaryl carbonate and a dialkyl carbonate and recovering the diaryl carbonate from the reaction products. Use of the lead catalyst is effective in avoiding corrosion problems normally caused by other catalyst systems.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: November 24, 1992
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Shinsuke Fukuoka, Ryoji Deguchi, Masahiro Tojo
  • Patent number: 4661639
    Abstract: A process for producing cyclic olefins by catalytic hydration of cyclic olefins is disclosed, wherein the hydration is conducted in the presence of a crystalline aluminosilicate containing at least one member selected from the group consisting of titanium, zirconium, hafnium, chromium, molybdenum, tungsten, and thorium. The hydration reaction achieves high conversions and selectivities, and the catalytic activity is retained for a long time.
    Type: Grant
    Filed: May 28, 1985
    Date of Patent: April 28, 1987
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Masahiro Tojo, Yohei Fukuoka