Polyurethane foam laminates
CA 2120983 A1 · Owner: Arthurs, Trevor Curtis · Inventors: Arthurs, Trevor Curtis
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A structure is disclosed comprising a layer of polyurethane foam bonded to at least one layer of another material, especially a layer of fibreglass matte, a layer of cellulosic material e.g. cardboard and/or a layer of polyurethane foam. The layers are bonded together with an adhesive of polyethylene or polypropylene that has been grafted with an ethylenically unsaturated dicarboxylic acid or anhydride thereof, the adhesive containing at least 0.03% by weight of said acid or anhydride. The structure exhibits a temperature for heat-fail resistance in shear of at least 90°C. In embodiments the polyurethane foam is a rigid polyurethane foam and, the polyethylene and polypropylene have been …
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 April 11, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 11, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 11, 2016.
- 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.