Process to reduce propenyl polyethers in hydroxy-functional polyethers
CA 2046945 C · Owner: Plepys, Raymond A. · Inventors: Mcclure, Craig A.; Chavez, Johnny Jr.; Gerstle, Richard N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for reducing the amount of propenyl polyethers in hydroxy-functional polyethers comprising (1) contacting a neutral hydroxy-functional polyether containing a propenyl polyether and water and an acid, catalyst soluble in the hydroxy-functional polyether under reaction conditions sufficient to convert at least a portion of the propenyl polyether to propionaldehyde; (2) contacting the product of step (1) and an epoxy compound to substantially scavenge the acid catalyst; and (3) stripping the product of step (2) to substantially remove the epoxy compound and the propionaldehyde. The resulting hydroxy-functional polyethers contain reduced amounts of propenyl polyethers and can …
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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 July 12, 1991 and granted July 10, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 12, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 12, 2013.
- 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.