Naphthylamine polycarboxylic acids
CA 2074335 A1 · Owner: Carter, Charles Garvie · Inventors: Carter, Charles Garvie; Fan, Lai-Duien Grace; Kreh, Robert Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A composition useful for treating aqueous systems comprising a naphthylamine polycarboxylic acid having the formula:, wherein X is CO2H or SO3H, Y is H C1 to C6 alkyl, CO2H or, SO3H, R is H, C1 to C6 alkyl CO2R' or COR', R' is C1 to C6, alkyl, n is an integer from 1 to 20 and water soluble, salts thereof.
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
- Filed July 21, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 21, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 21, 2014.
- 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.