Process for making pen/pet blends and transparent articles therefrom
CA 2274127 A1 · Owner: Schmidt, Steven L. · Inventors: Agrawal, Amit S.; Schmidt, Steven L.; Lynch, Brian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for controlling the change of intrinsic viscosity and transesterification during solid stating of a polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) blend with an effective amount of an , alkylene glycol compound. The process enables the production of a copolymer based on predefined initial and final IV's and final transesterification level, by varying the solid-stating time and/or effective amount of alkylene glycol. In one embodiment, a relatively greater amount of post-consumer PET (e.g. 70 %) having an IV of on the order of 0.72-0.73 is incorporated in the , blend to provide a final IV on the order of 0.80-0.85 and a moderate, controlled level of …
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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 December 5, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 5, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 5, 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.