Recovery of herbicidal esters
CA 1106392 A · Owner: Shell Canada Limited · Inventors: Wood, Derek A.; Montijn, Paulus P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for the recovery of N-benzoyl-N-(3,4-dihalophenyl)-2aminopropionic acid esters from mixtures by treatment with an aqueous base, followed by treatment with a water-immiscible organic solvent; acidifying the aqueous phase with a mineral acid; esterifying the liberated carboxylic acid(s) with a lower alkanol and optionally benzoylating the esterified product.
Read the whole patent
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 August 4, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 4, 1998.
- 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.