Process for melt extrusion of polymers
CA 2027098 C · Owner: Priester, Donnan Edwin · Inventors: Chapman, George Richard, Jr.; Mcminn, Rita Sue; Priester, Donnan Edwin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
TITLE, Improved Process For Melt Extrusion of Polymers ABSTRACT OF THE DISCLOSURE, The invention is a process comprising melt extruding through an extrusion die a composition comprising a difficulty-melt-processible polymer and 0.002 - 2 parts by weight, based on the weight of the polymer, of at least one melt-processible fluorocarbon polymer processing aid, said fluorocarbon polymer processing aid having a fluorine to carbon ratio of at least 1:2, wherein the extruder die surface is coated with one or more metal oxides, MxOy, wherein M is a metal selected from the group Ti, Zr, Cr Fe, Ni, Pd, Pt, Cu, Ag, Au, Al and Si, and x and y are selected to satisfy the valencies of M, and wherein …
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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 October 5, 1990 and granted August 16, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 5, 2012.
- 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.