Patents by Inventor Etsuo Yoshioka

Etsuo Yoshioka 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: 9340630
    Abstract: A solid polymethylaluminoxane composition is provided having uniform particle diameter in the form of fine particles of less than 5 ?m employed to polymerize olefins with high polymerization activity without silica. A method for manufacturing thereof, a polymerization catalyst, and a method for manufacturing a polyolefin are also provided. The solid polymethylaluminoxane composition: has an aluminum content within a range of 36 mass % to 43 mass %; has a mole fraction of methyl groups derived from trimethylaluminum moieties relative to the total number of mols of methyl groups of 12 mol % or less; and is particulate having a median diameter based on volume within a range of 0.1 ?m to less than 5 ?m. In a step of heating an aromatic hydrocarbon solution containing trimethylaluminum and the polymethylaluminoxane to cause solid polymethylaluminoxane composition to precipitate, prior to or during the heat treating step, a dry, inert gas is bubbled through.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: May 17, 2016
    Assignee: TOSOH FINECHEM CORPORATION
    Inventors: Eiichi Kaji, Etsuo Yoshioka
  • Patent number: 8975209
    Abstract: Disclosed is a solid support-polymethylaluminoxane complex exhibiting a higher polymerization activity than a conventional substance and being homogeneous. Also disclosed is a method for producing an olefin-based polymer having a favorable quality using the complex and a transition metal compound. The complex comprises a coating layer containing polymethylaluminoxane and trimethylaluminum on the surface of a solid support. The coating layer comprises a solid polymethylaluminoxane composition in which (i) the content of aluminum is in a range of 36 to 41 mass % and (ii) the molar fraction of methyl groups derived from a trimethylaluminum moiety to the total number of moles of methyl groups is 12 mol % or less. Also disclosed is an olefin polymerization catalyst comprising the complex and a transition metal compound represented by general formula (III): MR5R6R7R8 as catalyst components, and a method for producing a polyolefin comprising polymerizing an olefin using the catalyst.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: March 10, 2015
    Assignee: Tosoh Finechem Corporation
    Inventors: Eiichi Kaji, Etsuo Yoshioka
  • Publication number: 20150057418
    Abstract: A solid polymethylaluminoxane composition is provided having uniform particle diameter in the form of fine particles of less than 5 ?m employed to polymerize olefins with high polymerization activity without silica. A method for manufacturing thereof, a polymerization catalyst, and a method for manufacturing a polyolefin are also provided. The solid polymethylaluminoxane composition: has an aluminum content within a range of 36 mass % to 43 mass %; has a mole fraction of methyl groups derived from trimethylaluminum moieties relative to the total number of mols of methyl groups of 12 mol % or less; and is particulate having a median diameter based on volume within a range of 0.1 ?m to less than 5 ?m. In a step of heating an aromatic hydrocarbon solution containing trimethylaluminum and the polymethylaluminoxane to cause solid polymethylaluminoxane composition to precipitate, prior to or during the heat treating step, a dry, inert gas is bubbled through.
    Type: Application
    Filed: March 15, 2013
    Publication date: February 26, 2015
    Inventors: Eiichi Kaji, Etsuo Yoshioka
  • Patent number: 8404880
    Abstract: Disclosed are: a solid polymethylaluminoxane composition which does not utilize silica or the like, has the form of relatively fine particles, has more uniform particle sizes, and exhibits a high polymerization activity when used in the preparation of an olefin polymer; a process for producing the solid polymethylaluminoxane composition; a polymerization catalyst; and a process for producing an olefin polymer.
    Type: Grant
    Filed: November 11, 2009
    Date of Patent: March 26, 2013
    Assignee: Tosoh Finechem Corporation
    Inventors: Eiichi Kaji, Etsuo Yoshioka
  • Publication number: 20130059990
    Abstract: Disclosed is a solid support-polymethylaluminoxane complex exhibiting a higher polymerization activity than a conventional substance and being homogeneous. Also disclosed is a method for producing an olefin-based polymer having a favorable quality using the complex and a transition metal compound. The complex comprises a coating layer containing polymethylaluminoxane and trimethylaluminum on the surface of a solid support. The coating layer comprises a solid polymethylaluminoxane composition in which (i) the content of aluminum is in a range of 36 to 41 mass % and (ii) the molar fraction of methyl groups derived from a trimethylaluminum moiety to the total number of moles of methyl groups is 12 mol % or less. Also disclosed is an olefin polymerization catalyst comprising the complex and a transition metal compound represented by general formula (III): MR5R6R7R8 as catalyst components, and a method for producing a polyolefin comprising polymerizing an olefin using the catalyst.
    Type: Application
    Filed: May 11, 2011
    Publication date: March 7, 2013
    Applicant: Tosoh Finechem Corporation
    Inventors: Eiichi Kaji, Etsuo Yoshioka
  • Publication number: 20110282017
    Abstract: Disclosed are: a solid polymethylaluminoxane composition which does not utilize silica or the like, has the form of relatively fine particles, has more uniform particle sizes, and exhibits a high polymerization activity when used in the preparation of an olefin polymer; a process for producing the solid polymethylaluminoxane composition; a polymerization catalyst; and a process for producing an olefin polymer.
    Type: Application
    Filed: November 11, 2009
    Publication date: November 17, 2011
    Applicant: Tosoh Finechem Corporation
    Inventors: Eiichi Kaji, Etsuo Yoshioka