Patents by Inventor Kunitoshi Wakabayashi

Kunitoshi Wakabayashi 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: 6153708
    Abstract: A highly polymerizable N-vinylcarboxylic acid amide having an N-1,3-butadienylcarboxylic acid amide content of 30 ppm or less, a process for producing the same, and a process for producing a homopolymer of N-vinylcarboxylic acid amide or a copolymer thereof with another copolymerizable monomer using the same. Also, a highly polymerizable N-vinyl-carboxylic acid amide is produced by thermal cracking or catalytic cracking of N-(1-alkoxyethyl)carboxylic acid amide or ethylidenebiscarboxylic acid amide, wherein the N-vinyl-carboxylic acid amide content of the N-(1-alkoxyethyl)-carboxylic acid amide or ethylenebiscarboxylic acid amide is 10 wt % or less.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: November 28, 2000
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Tetsuo Kudo, Kunitoshi Wakabayashi, Kenji Shimamura, Shun-ichi Nagamatsu
  • Patent number: 6143836
    Abstract: A highly polymerizable N-vinylcarboxylic acid amide having an N-1,3-butadienylcarboxylic acid amide content of 30 ppm or less, a process for producing the same, and a process for producing a homopolymer of N-vinylcarboxylic acid amide or a copolymer thereof with another copolymerizable monomer using the same. Also, a highly polymerizable N-vinylcarboxylic acid amide is produced by thermal cracking or catalytic cracking of N-(1-alkoxyethyl)carboxylic acid amide or ethylidenebiscarboxylic acid amide, wherein the N-vinylcarboxylic acid amide content of the N-(1-alkoxyethyl)carboxylic acid amide or ethylenebiscarboxylic acid amide is 10 wt % or less.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: November 7, 2000
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Tetsuo Kudo, Kunitoshi Wakabayashi, Kenji Shimamura, Shun-ichi Nagamatsu
  • Patent number: 6072084
    Abstract: A highly polymerizable N-vinylcarboxylic acid amide having an N-1,3-butadienylcarboxylic acid amide content of 30 ppm or less, a process for producing the same, and a process for producing a homopolymer of N-vinylcarboxylic acid amide or a copolymer thereof with another copolymerizable monomer using the same. Also, a highly polymerizable N-vinylcarboxylic acid amide is produced by thermal cracking or catalytic cracking of N-(1-alkoxyethyl)carboxylic acid amide or ethylidenebiscarboxylic acid amide, wherein the N-vinylcarboxylic acid amide content of the N-(1-alkoxyethyl)carboxylic acid amide or ethylenebiscarboxylic acid amide is 10 wt % or less.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: June 6, 2000
    Assignee: Showa Denko K.K.
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Tetsuo Kudo, Kunitoshi Wakabayashi, Kenji Shimamura, Shun-ichi Nagamatsu
  • Patent number: 5892115
    Abstract: A highly polymerizable N-vinylcarboxylic acid amide having an N-1,3-butadienylcarboxylic acid amide content of 30 ppm or less, a process for producing the same, and a process for producing a homopolymer of N-vinylcarboxylic acid amide or a copolymer thereof with another copolymerizable monomer using the same. Also, a highly polymerizable N-vinylcarboxylic acid amide is produced by thermal cracking or catalytic cracking of N-(1-alkoxyethyl)carboxylic acid amide or ethylidenebiscarboxylic acid amide, wherein the N-vinylcarboxylic acid amide content of the N-(1-alkoxyethyl)carboxylic acid amide or ethylenebiscarboxylic acid amide is 10 wt % or less.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: April 6, 1999
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Tetsuo Kudo, Kunitoshi Wakabayashi, Kenji Shimamura, Shun-ichi Nagamatsu
  • Patent number: 5789619
    Abstract: A highly polymerizable N-vinylcarboxylic acid amide having an N-1,3-butadienylcarboxylic acid amide content of 30 ppm or less, a process for producing the same, and a process for producing a homopolymer of N-vinylcarboxylic acid amide or a copolymer thereof with another copolymerizable monomer using the same. Also, a highly polymerizable N-vinyl carboxylic acid amide is produced by thermal cracking or catalytic cracking of N-(1-alkoxyethyl)carboxylic acid amide or ethylidenebiscarboxylic acid amide, wherein the N-vinylcarboxylic acid amide content of the N-(1-alkoxyethyl)carboxylic acid amide or ethylenebiscarboxylic acid amide is 10 wt % or less.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: August 4, 1998
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Tetsuo Kudo, Kunitoshi Wakabayashi, Kenji Shimamura, Shun-ichi Nagamatsu
  • Patent number: 5362918
    Abstract: A process for producing acetaldehyde dimethylacetal comprising reacting acetaldehyde and methanol in the presence of an acid catalyst is disclosed, in which the reaction is carried out in a part of a rectification tower while conducting rectification to withdraw the water by-produced from the bottom of the tower and to recover a distillate containing the acetaldehyde dimethylacetal produced from the top of the tower. The distillate is subjected to azeotropic distillation in the presence of n-hexane or cyclohexane to separate methanol as an azeotrope with n-hexane or cyclohexane and a small amount of the acetaldehyde dimethylacetal and to recover high purity acetaldehyde dimethylacetal as a bottom.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: November 8, 1994
    Assignee: Showa Denko K.K.
    Inventors: Toshiyuki Aizawa, Hitoshi Nakamura, Kunitoshi Wakabayashi, Tetsuo Kudo, Hiroyuki Hasegawa