Method of producing polyurethane foam
CA 2265641 A1 · Owner: Yokota, Hiroshi · Inventors: Yokota, Hiroshi; Nishikawa, Shinji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A low-density semi-rigid polyurethane foam having excellent wear resistance which is demolded in a short time, can be prepared by a method of producing a polyurethane foam having microcell and a density of 0.3 to 0.9/cm3 by a reaction injection molding process from, a polyisocyanate, and a polyol mixture containing a polyol a catalyst, a blowing agent, and optionally a cross-linking agent an internal, mold release agent, a reinforcing agent and an other aid characterized in that a trifunctional polyether polyol having an active hydrogen equivalent of 300 to 1,000 and an ethylene oxide content of 5 to 30 % by weight is contained in an amount of at least 40 % by weight based on the polyether …
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 September 9, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 9, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 9, 2019.
- 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.