Thin foamed polyethylene sheets
CA 2531557 C · Owner: Martinez, Felipe · Inventors: Martinez, Felipe
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to the use of particular blends of LLDPE and LDPE together with specific fabrication conditions to make foamed sheets of thin gauge with MD tear properties similar to an equivalent gauge non-foamed sheet of the same composition. In particular blends which combine a high MI , LLDPE rich fraction with a low MI branched LDPE minor fraction provide the adequate balance of mechanical strength of the polymer base with its melt strength, extensibility and stress relaxation allowing a thin foam film with , MD tear strength which is comparable to non foamed counterparts of similar gauge and composition. The foamed films of the present invention are thin …
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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 June 30, 2004 and granted February 19, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 30, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 30, 2026.
- 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.