Patents by Inventor Katsuhiro Kamakari

Katsuhiro Kamakari 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).

  • Process for producing a polyvinyl acetacetal resin for use in a heat transfer sheet
    Patent number: 5068282
    Abstract: A heat transfer sheet comprises a substrate sheet and a heat transfer layer laminated on the substrate sheet and containing a dye which can be caused to migrate by heating to be transferred onto a transferable sheet, said heat transfer sheet containing a polyvinyl acetacetal resin as a binder component, the acetal moiety of said polyvinyl acetacetal resin being 50% by weight or more based on the total amount of the resin, and 80% by weight or more of said acetal moiety comprising polyvinyl acetacetal.A process for producing a polyvinyl acetacetal resin by the reaction of a polyvinyl alcohol and acetaldehyde in an aqueous phase in the presence of 4 to 10% by weight of an acid catalyst comprises initiating precipitation of an acetalated product by maintaining the reaction system at a temperature of 8.degree. to 17.degree. C. for 30 minutes or longer, and then maintaining said reaction at a temperature of 25.degree. to 40.degree. C.
    Type: Grant
    Filed: October 30, 1989
    Date of Patent: November 26, 1991
    Assignees: Dai Nippon Insatsu Kabushiki Kaisha, Sekisui Kagaku Kogyo Kabushiki Kaisha
    Inventors: Jumpei Kanto, Masanori Akada, Katsuhiro Kamakari, Kenichi Asahina, Katsuaki Sakashita, Yoshihisa Watanabe
  • Heat transfer sheet
    Patent number: 4933315
    Abstract: A heat transfer sheet to be used for heat-sensitive transfer, comprising a substrate sheet and a dye layer formed on said substrate sheet, said dye layer being constituted of a layer containing a yellow dye, a cyan dye, and a magenta dye comprising a specific compound having phenylene-diamine or its derivative as the developer.
    Type: Grant
    Filed: February 17, 1988
    Date of Patent: June 12, 1990
    Assignee: Dai Nippon Insatsu Kabushiki Kaisha
    Inventors: Jumpei Kanto, Hitoshi Saito, Nobuhisa Nishitani, Masaki Kutsukake, Tatsuya Kita, Masanori Akada, Masayuki Nakamura, Katsuhiro Kamakari
  • Heat transfer sheet
    Patent number: 4902670
    Abstract: A heat transfer sheet comprises a substrate sheet and a heat transfer layer laminated on the substrate sheet and containing a dye which can be caused to migrate by heating to be transferred onto a transferable sheet, said heat transfer sheet containing a polyvinyl acetacetal resin as a binder component, the acetal moiety of said polyvinyl acetacetal resin being 50% by weight or more based on the total amount of the resin, and 80% by weight or more of said acetal moiety comprising polyvinyl acetacetal.A process for producing a polyvinyl acetacetal resin by the reaction of a polyvinyl alcohol and acetaldehyde in an aqueous phase in the presence of 4 to 10% by weight of an acid catalyst comprises initiating precipitation of an acetalated product by maintaining the reaction system at a temperature of 8.degree. to 17.degree. C. for 30 minutes or longer, and then maintaining said reaction at a temperature of 25.degree. to 40.degree. C.
    Type: Grant
    Filed: December 11, 1987
    Date of Patent: February 20, 1990
    Assignees: Dai Nippon Insatsu Kabushiki Kaisha, Sekisui Kagaku Kogyo Kabushiki Kaisha
    Inventors: Jumpei Kanto, Masanori Akada, Katsuhiro Kamakari, Kenichi Asahina, Katsuaki Sakashita, Yoshihisa Watanabe