Solvent scrubbing recovery of lactide and other dimeric cyclic esters
CA 2093354 A1 · Owner: Bhatia, Kamlesh Kumar · Inventors: Kosak, John Richard; Bhatia, Kamlesh Kumar; Drysdale, Neville Everton
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved process for the recovery of lactide or other dimeric cyclic ester from a gas stream containing the cyclic ester and such hydroxylic impurities as water and open-chain hydroxycarboxylic acids by scrubbing the gas stream with a nonpolar water-immiscible solvent at a temperature at which the cyclic ester is removed from the solvent and any water present in the gas stream is vaporized from the solvent. The cyclic ester is recovered from the solvent in a high state of optical purity.
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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 October 15, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 15, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 15, 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.