Methods and devices for purifying polyolefin
CA 2129451 C · Owner: Lorenz, Arnulf · Inventors: Lorenz, Arnulf
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Described are methods of removing solvent residues and/or nitrocellulose residues from a pre-purified polyolefin, in particular from pre-purified polyethylene recycling cuts, the polyolefin either being treated with washing water, the solvent driven off and simultaneously the nitrocellulose washed out of the polyolefin or the, polyolefin being washed with purified solvent the solvent, separated off mechanically and the solvent residues remaining with the polyolefin expelled by a stream of nitrogen. Also described are devices for carrying out these methods.
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 16, 1993 and granted April 6, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 16, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 16, 2015.
- 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.