Process for preparing a cationically modified (meth)acrylamide polymer and use of the polymer
CA 2306797 A1 · Owner: Ahlgren, Jonni · Inventors: Petander, Lars; Ahlgren, Jonni; Nikkarinen, Jussi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a process for preparing a cationically modified (meth)acrylamide polymer by the Mannich reaction. There is prepared in advance a stable aldehyde-secondary amine adduct which is obtained as a reaction , product of an aqueous solution of the secondary amine and an aqueous solution of the aldehyde, and which, after the formation of the adduct is stabilized , to endure storage, by lowering the pH of the mixture of 7 or below and/or by adding methanol, and the adduct thus prepared is added to an aqueous solution of the (meth)acrylamide polymer and the pH is adjusted to an alkaline level whereupon modification occurs. The invention also relates to the use of the …
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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 October 29, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 29, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 29, 2020.
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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.