Patents by Inventor Alain Sigismondi

Alain Sigismondi 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).

  • Preparation of citraconic anhydride
    Patent number: 5670659
    Abstract: Citraconic anhydride is prepared in a single step by heating itaconic acid, optionally in an inert organic solvent medium, in the presence of a catalytically effective amount of an at least partially organic acid/base catalyst compound having a pKa ranging from 4 to 10, in particular a salt catalyst such as pyridinium tosylate, itaconate or hydrochloride, ammonium itaconate, or phosphinium hydrobromide.
    Type: Grant
    Filed: January 30, 1995
    Date of Patent: September 23, 1997
    Assignee: Rhone-Poulenc Chimie
    Inventors: Michel Alas, Alain Sigismondi, Philippe-Jean Tirel