Removal of ferric chloride from halopyridines
CA 1264756 C · Owner: The Dow Chemical Company · Inventors: Friese, David D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Ferric chloride is removed from mixtures with chlorinated and/or fluorinated pyridines and methylpyridines by extraction with diol solvents. For example the ferric chloride in halopyridine mixtures containing 2,3,5,6-tetrachloropyridine was removed by extraction with ethylene glycol. The purified halopyridines are useful intermediates for the production of insecticides herbicides, and fungicides.
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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
- Granted January 23, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 23, 2007.
- 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.