Process for the recovery of perfluoroethercarboxylic acids
CA 2058338 A1 · Owner: Ginzel, Klaus-Dieter · Inventors: Ebmeyer, Frank; Ginzel, Klaus-Dieter; Gries, Thomas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract:, Process for the recovery of perfluoroethercarboxylic acids, The invention relates to a process for the recovery of perfluoroethercarboxylic acids from the crude product of the electrochemical conversion of these acids or of one of their soluble salts to perfluorinated ethers in which, the perfluoroethercarboxylic acids and their esters contained in the crude product are separated off with the aid of a solid basic alkali metal salt or its solution and converted, by reaction of the resulting salts with a strong acid, to the corresponding perfluoroethercarboxylic acids.
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 December 23, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 23, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 23, 2013.
- 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.