Process for the inhibition of scale in harsh systems and novel antiscalants for same
CA 2340057 A1 · Owner: Morris, John David · Inventors: Reed, Peter Edward; Duggirala, Prasad Yogendra; Morris, John David
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Improved process for inhibiting calcium carbonate scaling in aqueous systems such as that employed in the Kraft pulping process. Such an improved process is achieved by the addition of at least one antiscalant comprising one monomer unit derived from the group consisting of 1,2-dihydroxy-3-butene N-, (hydroxymethyl)acrylamide and N-(sulfoxymethyl)acrylamide and at least one , monomer unit derived from the group consisting of maleic acid acrylic acid, acrylamide, methacrylic acid itaconic acid, vinyl sulfonic acid, styrene sulfonic acid, N-tertbutylacrylamide, butoxymethylacrylamide N,N-, dimethylacrylamide, sodium acrylamidomethyl propane sulfonic acid and salts , thereof.
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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 June 21, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 21, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 21, 2021.
- 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.