Polyether resins, and process for preparing the same
CA 2005477 C · Owner: Andre, Olivier L.P. · Inventors: Andre, Olivier L.P.; Scholten, Henricus P.H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the preparation of a polyether resin having an epoxy group content of less than 0.2 meq/g and containing on average from (see formula I)to (see formula II) primary hydroxyl groups, by reacting a glycidyl ester of a C9-11 branched aliphatic acid with an aliphatic primary polyhydric alcohol having n primary hydroxyl groups, and 5 to 16 carbon atoms, n having a value of 3 to 6, in the presence of an etherification catalyst characterised in that the etherification catalyst is a tin, zinc or iron compound.
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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 December 14, 1989 and granted August 29, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 14, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 14, 2011.
- 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.