Patents Assigned to Showa Kagaku Kogyo Co., Ltd
  • Color salt-containing optical brightener composition
    Patent number: 4388079
    Abstract: This invention relates to an optical brightener composition comprising at least one optical brightener and at least one color salt consisting of an optical brightener component having at least one anionic group and a color component having at least one basic group capable of forming a slat with the anionic group, which composition has an excellent brightening effect capable of giving a clearer whiteness as well as a high light fastness.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: June 14, 1983
    Assignee: Showa Kagaku Kogyo Co., Ltd.
    Inventors: Kazuaki Suzuki, Shohei Kuwabara
  • Color salts of basic dyes with acidic optical brighteners of stilbene type
    Patent number: 4374643
    Abstract: This invention relates to a novel color salt or color complex consisting of an optical brightener component having at least one anionic group and a color component having at least one basic group capable of forming a salt with the anionic group. This color salt is capable of coloring various fibrous articles, paper, pulp, leathers, rubbers, adhesives and plastics in clear and brightened color.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: February 22, 1983
    Assignee: Showa Kagaku Kogyo Co., Ltd
    Inventors: Kazuaki Suzuki, Shohei Kuwabara