Improved method for producing polytetrahydrofuran
CA 2297726 A1 · Owner: Hesse, Michael · Inventors: Hesse, Michael; Eller, Karsten; Becker, Rainer
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 polymerising tetrahydrofuran in the presence of at least one telogen and/or comonomer on a heterogeneous catalyst. The invention is characterised in that the catalyst used is hectorite.
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 August 21, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 21, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 21, 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.