Method for producing polytetrahydrofuran
CA 2294028 A1 · Owner: Becker, Rainer · Inventors: Becker, Rainer; Plitzko, Klaus-Dieter; Sigwart, Christoph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method for producing polytetrahydrofuran polytetrahydrofuran copolymers, diesters or monoesters of these polymers by polymerization of tetrahydrofuran in the presence of at least one telogene and/or comonomer on a sulfate-containing heterogeneous supported catalyst. A sulfate-containing heterogeneous supported catalyst is used containing at least one metal sulfate, metal hydrogen sulfate metal oxide sulfate or , mixtures thereof.
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 June 10, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 10, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 10, 2020.
- 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.