Polyethers and polysiloxane copolymers manufactured with double metal cyanide catalysts
CA 2211775 C · Owner: Miller, Glenn A. · Inventors: Jorgenson, Michael W.; Budnik, Richard; Miller, Glenn A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention discloses a new class of silicone surfactants and their use for the preparation of flexible urethane foam. The surfactants incorporate high molecular weight polyethers prepared with narrower molecular weight distributions than conventional polyethers. These polyethers are prepared using a double metal cyanide (DMC) catalyst. These surfactants are better foam stabilizers than the analogoussurfactants prepared from conventional polyethers.
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 July 30, 1997 and granted November 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 30, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 30, 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.