Isotropic rigid foams
CA 2410367 A1 · Owner: Steppan, David D. · Inventors: Steppan, David D.; Ball, Edward E.; Bushmire, Alan D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a process for the preparation of an isotropic rigid foam comprising the step of reacting: (A) an organic polyisocyanate component selected from the group consisting of: (1) a polymethylene poly(phenylisocyanate) and (2) an NCO-terminated prepolymer and, comprising the reaction product of: (a) a polyester comprising the reaction product of (i) pure ortho-phthalic acid or phthalic anhydride and (ii) a glycol, and (b) a polymethylene poly(phenylisocyanate); with (B) an isocyanatereactive component comprising: (1) a liquid OH-terminated prepolymer having a viscosity of more than about 100,000 mPa.s at 25°C and which , comprises, the reaction product of: (a) an organic …
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 October 30, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 30, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 30, 2024.
- 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.