Patents by Inventor Yves Darche

Yves Darche 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 the production of lower dialkyl disulphides
    Patent number: 5001269
    Abstract: The invention relates to the production of dialkyl disulphides of the R-SS-R type where R represents an alkyl radical having from 1 to 3 carbon atoms, by oxidation of the corresponding alkyl mercaptan R--SH by sulphur in the presence of a catalyst.A combination of an alkyl mercantap R'--SH with an alkylene oxide and an alkaline base is used as catalyst, R' representing an alkyl radical having from 6 to 18 carbon atoms.This catalyst enables a lower dialkyl disulphide of excellent quality to be obtained (absence of amine and coloration).
    Type: Grant
    Filed: April 3, 1989
    Date of Patent: March 19, 1991
    Assignee: Societe Nationale Elf Aquitaine (Production)
    Inventors: Henri Gongora, Yves Darche
  • Process for the production of organic polysulphides and catalyst system for its use
    Patent number: 4876389
    Abstract: Process for the production of organic polysulphides of the type R--S.sub.n --R, where R is a hydrocarbon group and n a number from 2 to 8, by heating one or more mercaptans with sulphur, in the presence of a catalyst; the catalyst consists of the combination of a mercaptan with an alkene oxide and an alkaline base.
    Type: Grant
    Filed: November 27, 1987
    Date of Patent: October 24, 1989
    Assignee: Societe Nationale Elf Aquitaine (Production)
    Inventors: Henri Gongora, Yves Darche