Drying temperature independent polytetrafluoroethylene
CA 2059593 A1 · Owner: Mellish, Walter George · Inventors: Mellish, Walter George
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a product and method of incrementally adding comonomers to co-polytetrafluoroethylene (PTFE) by an improved process, resulting in a PTFE product independent and/or much less dependent upon drying temperatures. The improved PTFE exhibits increased green strength at substantially constant extrusion pressures and an extrusion pressure that is substantially independent of drying temperatures of the wet PTFE.
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 January 17, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 17, 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.