Sophisticated process for the production of alkyl (meth)acrylates by direct esterification
CA 2114277 C · Owner: Richard, Norbert · Inventors: Richard, Norbert; Colin, Nadine; Esch, Marc
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to the preparation of an alkyl methacrylate by direct esterification (in 1) of methacrylic acid by the corresponding alcohol catalyzed by H2S04. A base is added (in 3) to the crude reaction mixture (B1) which contains the ester in question, alcohol methacrylic acid, alkyl acid sulphate and traces of H2S04 to neutralize the acid species. The resulting salts pass into the aqueous phase (A1) which is separated from the organic phase (01) containing the ester in question. The light products (L1) containing alcohol are recovered (in 4) from the aqueous phase and the waste waters (E2) are eliminated. The alkyl sulphate acid present in the aqueous phase (A1) resulting from …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 26, 1994 and granted June 23, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 26, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 26, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.