Amides of acids of phosphorus for the extraction of metals
CA 2177064 A1 · Owner: Quan, Peter Michael · Inventors: Campbell, John; Cupertino, Domenico Carlo; Dalton, Raymond Frederick
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compounds of formula (I), wherein R1 is an optionally substituted 2alkylphenoxy group, each of R2, R3 and R4 is a group selected from optionally substituted 2-alkylphenoxy, optionally substituted phenyl optionally , substituted alkyl and optionally substituted alkoxy and at least one optionally substituted 2-alkylphenoxy group has a tertiary alkyl substituent except the compound wherein each of R1 and R2 is 2-isopropyl-4-<u>tert</u>nonylphenoxy and each of R3 and R4 is phenyl and the compound wherein R1 is 2methyl-4-<u>tert</u>-nonylphenoxy, R2 is 2,4-dimethylphenoxy and each of R3 and R4 is phenyl. Compounds of formula (I) are useful for the solvent extraction of metals, especially …
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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 November 11, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 11, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 11, 2016.
- 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.