Patents by Inventor Jean-Louis Herisson

Jean-Louis Herisson 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: 4481343
    Abstract: The process for the polymerization in aqueous dispersion of tetrafluoroethylene in the presence of an emulsifier and an initiator, with the latter yielding free radicals between 0.degree. and 45.degree. C. and being destroyed for a temperature above 45.degree. C., characterized by the fact that the temperature of the reaction medium as a function of polymerization time is made to follow an ascending curve, Temperature .degree.C. versus t (time in minutes) whose slope (.DELTA.T/.DELTA.t) cannot be less than 1/6, .DELTA.T representing the temperature in .degree.C. at a given time in minutes .DELTA.t, with this ascending curve being situated inside of a sector limited by two straight lines y=(7/12)x and y=(15/7)x+45, in which y and x respectively represent the temperature in .degree.C. and the time expressed in minutes, and by the fact that the initiator is destroyed before the concentration of polytetrafluoroethylene in the dispersion has reached 20%.
    Type: Grant
    Filed: November 12, 1980
    Date of Patent: November 6, 1984
    Assignee: Produits Chimiques Ugine Kuhlmann
    Inventor: Jean-Louis Herisson
  • Patent number: 4384092
    Abstract: A treatment procedure for aqueous colloidal polytetrafluoroethylene dispersions obtained by polymerization of tetrafluoroethylene in the presence of the lithium salt of a perfluoroalkanesulfonic acid as the emulsifier, characterized by the fact that a basic hydroxide or a soluble ammonium, alkali metal or alkaline-earth salt, with the exception of lithium hydroxide or a lithium salt, is added to the dispersion.
    Type: Grant
    Filed: April 24, 1981
    Date of Patent: May 17, 1983
    Assignee: Produits Chimiques Ugine Kuhlmann
    Inventors: Jean Blaise, Jean-Louis Herisson