Process for producing extruded foam with co2 as a blowing agent
CA 2344338 C · Owner: Owens Corning Intellectual Capital, Llc · Inventors: Breindel, Raymond M.; Miller, Larry M.; Weekley, Mitchell Z.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In one embodiment, the present invention relates to a process for preparing a foam product involving the steps of (A) forming a foamable mixture of (1) a polymer comprising about 10 % to about 90 % monomers of at least one of metasubstituted styrene and para-substituted styrene and 0 % to about 90 % monomers of styrene, and (2) a blowing agent containing a major amount of carbon dioxide under a pressure sufficient to prevent prefoaming of the mixture and (B) foaming the mixture into a region of reduced pressure to form the foam product.
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 12, 1999 and granted November 15, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 12, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 12, 2021.
- 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.