Method for manufacturing a partitioned paperboard food tray
CA 2173004 C · Owner: Westvaco Corporation · Inventors: Rigby, William Roger
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for manufacturing a composite food packaging article having internal partitioning walls constructed from flat, machine formed paperboard. A pair of die-cut and folded paperboard blanks are inserted within the opposing cavities of a blow mold. A hot-flow parison between the cavities expands to structurally unitize the folded paper blank into a fluid impermeable tray vessel.
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 August 24, 1993 and granted February 3, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 24, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 24, 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.