Elevated temperature dimensionally stable polyester with low gas permeability
CA 2129446 C · Owner: Dalgewicz, Edward J. Iii · Inventors: Freundlich, Richard A.; Dalgewicz, Edward J. Iii; Bond, John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides crystalline polyester articles having an oxygen permeability of from about 0.2 to about 4.9 cc-mil/ (00 in2-24 hr-atm, and an enthalpy of recrystallization of from about 0 to about -2.1 cal/g. They are prepared by; a) heating a crystallizable polyester above the temperature of its peak rate of crystallization from melt, b) shaping it at or above this crystallization temperature in a heated form and c) cooling it at a rate of about 5 °C to 80 °C per minute. The polyester articles are useful as containers for microwavable ovenable and/or frozen , foods. They have good gas barrier properties and, postmold dimensional sta bility from about -60 °C to about 200 °C.
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 February 3, 1993 and granted April 17, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 3, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 2015.
- 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.