Process for the preparation of fluorinated polyethers
CA 2073359 A1 · Owner: Hoechst Aktiengesellschaft · Inventors: Gries, Thomas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the disclosure: Process for the preparation of fluorinated polyethers The invention relates to a process for the preparation of fluorinated polyethers of the formula I Rf-O-(C2F4)-(C2F4)-O-Rf (I), in which Rf is a straight-chain branched or cyclic, fluoroalkyl or fluoroalkyl ether radical and the two (C2F4) groups, independently of each other have the, structure (CF2-CF2) or (CF(CF3)) from fluorovinyl ethers, of the formula II Rf-O-CF=CF2 (II), in which Rf has the same meaning as in formula I. For this, the liquid fluorovinyl ether (II) or the, fluorovinyl ether (II) dissolved in an inert solvent is reacted with gaseous elemental fluorine which is used, undiluted or diluted with …
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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 July 8, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 8, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 8, 2014.
- 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.