Haze free polyether polyol compositions and a method for their preparation
CA 2298264 C · Owner: Betke, Brian J. · Inventors: Thankachan, Chacko; Welch, Michael C.; Betke, Brian J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Most generally, the invention provides a method for making a neutralized polyether polyol comprising the steps of a) Polymerizing one or more alkylene oxides in the presence of an alkaline catalyst to form a polyalkylene oxide intermediate; and b) Neutralizing the intermediate after the polymerization step a) is complete with an organic acid of general formula where R1 is hydrogen, methyl, or ethyl; R2 is methyl or ethyl; and R3 is an alkyl aryl, or aralkyl group containing one to twelve carbon atoms. The invention also comprises the novel compositions made by the above process.
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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 February 7, 2000 and granted September 23, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 7, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 7, 2022.
- 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.