Patents by Inventor Norio Kondo

Norio Kondo 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).

  • Production of wet-strength paper with aqueous solutions of cationic thermosetting resins
    Patent number: 4336835
    Abstract: A durable aqueous solution of a thermosetting resin having a relatively high solid content which imparts a high degree of wet strength to paper, is produced by the reaction of an aliphatic dicarboxylic acid with a polyalkylenepolyamine to form a polyamidopolyamine, which is successively subjected to reaction with epichlorohydrin, the first reaction being carried out using a molar ratio of aliphatic dicarboxylic acid to polyalkylenepolyamine of 1:1.0 to 1.2 and continued until the viscosity at 25.degree. C. of 50% aqueous solution of resulting polyamidopolyamine reaches 400 to 1,000 cps, and the second reaction being carried out using epichlorohydrin in an amount of 1.6 to 1.7 moles per mole of the polyamide secondary amine and continued until the viscosity at 25.degree. C. of 15% aqueous solution of the resulting product reaches 30 to 150 cps.
    Type: Grant
    Filed: April 14, 1981
    Date of Patent: June 29, 1982
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Hisao Takagishi, Norio Kondo
  • Production of aqueous solutions of cationic thermosetting resins
    Patent number: 4287110
    Abstract: A durable aqueous solution of a thermosetting resin having a relatively high solid content which imparts a high degree of wet strength to paper, is produced by the reaction of an aliphatic dicarboxylic acid with a polyalkylenepolyamine to form a polyamidopolyamine, which is successively subjected to reaction with epichlorohydrin, the first reaction being carried out using a molar ratio of aliphatic dicarboxylic acid to polyalkylenepolyamine of 1:1.0 to 1.2 and continued until the viscosity at 25.degree. C. of 50% aqueous solution of resulting polyamidopolyamine reaches 400 to 1,000 cps, and the second reaction being carried out using epichlorohydrin in an amount of 1.6 to 1.7 moles per mole of the polyamide secondary amine and continued until the viscosity at 25.degree. C. of 15% aqueous solution of the resulting product reaches 30 to 150 cps.
    Type: Grant
    Filed: September 25, 1979
    Date of Patent: September 1, 1981
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Hisao Takagishi, Norio Kondo
  • Transparentizing agent for paper
    Patent number: 4128437
    Abstract: A transparentizing composition for paper comprising a compound having the formula: ##STR1## or salts thereof and a solvent.
    Type: Grant
    Filed: May 28, 1976
    Date of Patent: December 5, 1978
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Shigeru Ura, Norio Kondo, Yoshiya Fukuyama, Makoto Nakahara