A process for polymerizing isocyanates
CA 2212074 A1 · Owner: Quiring, Bernd · Inventors: Nefzger, Hartmut; Quiring, Bernd
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Isocyanates are polymerized in a simple manner by polymerizing aliphatic and/or aromatic isocyanates in the presence of metallocenes at temperatures from20 to 220°C optionally subject to increased or reduced pressure and optionally in the presence of an inert organic solvent the metallocene being used in an amount of 5 to 50,000 ppm relative to the amount of isocyanates used.
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 July 31, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 31, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 31, 2019.
- 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.