Terpolymer of itaconic acid for high ph scale control
CA 2067533 A1 · Owner: Yorke, Monica · Inventors: Persinski, Leonard J.; Yorke, Monica; Matz, Gary F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
0980H C-1518, TITLE OF THE INVENTION, TERPOLYMER OF ITACONIC ACID FOR HIGH pH SCALE CONTROL ABSTRACT OF THE DISCLOSURE, A particular terpolymer of itaconic acid (IA) with acrylic acid (AA) and methacrylic acid (MAA) with a molar ratio of monomers of 25-35 M : 30-40 MAA : 30-45 IA, has been found to give excellent inhibition of scale, especially CaCO3 scale at, elevated pH I 8 of 8.5 - 9.5, when used either alone or in combination with phosphonates and acrylate based copolymers.
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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 29, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 29, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 29, 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.