Production of oriented plastics by roll-drawing
CA 2195580 C · Owner: Dumoulin, Michel M. · Inventors: Ajii, Abdellah; Dumoulin, Michel M.; Dufour, Jacques
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process and apparatus for the continuous solid state forming of semicrystalline polymers using roll-drawing is disclosed. The output of an extruded thick polymer profile is stabilized by a gear pump. The profile is passed through a die for the desired geometry and a cooling calibrator. The profile is heat conditioned in heating tunnels to a temperature below the melting point prior to deformation between sets of rolls. A plurality e.g. four, pairs of rolls apply both compression and tension to the polymer profile. The tension applied on the profile the, roll gap, the linear speed of the profile and its temperature are monitored and controlled for the amount of polymer deformation and …
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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 January 8, 1997 and granted June 12, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 8, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 8, 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.