Processes for producing citrate esters
CA 2290092 A1 · Owner: Chiu, Kuen-Wai · Inventors: Scriven, Eric F. V.; Grendze, Martin; Wyeth, John T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Described are processes for producing citrate esters in an economic fashion. Esters are prepared by esterification of a citric acid-containing fermentation broth having been treated to remove cations and optionally other impurities but containing sugar(s). Esters are also prepared by reacting an impure aqueous citric acid source with an alcohol to provide a heterogeneous acqueous/organic reacted mixture, wherein the organic phase contains the ester and the acqueous phase retains water-soluble impurities. A liquid phase separation is then used to separate the organic and aqueous phases conveniently separating the impurities from the product and avoiding the energy-intensive …
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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 May 12, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 12, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 12, 2020.
- 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.