Corrosion inhibition in highly acidic environments
CA 2067313 C · Owner: Zetlmeisl, Michael J. · Inventors: French, Eddie C.; Zetlmeisl, Michael J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for inhibiting corrosion of ferrous surfaces in an acidic, aqueous medium having a temperature of at least about 200°F is disclosed. The method comprises incorporating into the medium a corrosion inhibiting amount of a corrosion inhibitor comprising the reaction product of an aldehyde and a composition corresponding to the formula:, (see fig. I), wherein R1 is a hydrocarbon group R2 and R3 are independently, selected from H and alkyl R4 is H, alkyl, alkanol, or (alkylene-N)nH wherein n is at least one and x is 2 or, 3. The present invention is also directed to a such method in which the corrosion inhibitor comprises a compound corresponding to the formula: (see fig.II), wherein R1, …
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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 April 27, 1992 and granted September 29, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 27, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 27, 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
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.