Water-soluble allylphosphonate copolymers
CA 2050205 A1 · Owner: Grace (W. R.) & Co.-Conn. · Inventors: Quach, Loc
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to water-soluble allylphosphonate copolymers which are useful for treating aqueous systems. The allylphosphonate copolymers are characterized as having the formula:, wherein the molar percentage of x in the copolymer is from 1 to 90 percent, the molar percentage of y in the copolymer is from 10 to 99 percent, and the total of x and y being 100 percent; and wherein each R1 is independently selected from the group consisting of hydrogen, lower alkyl groups having from 1 to about 4 carbon atoms and a salt forming cation R2 and R3 are, independently selected from the group consisting of hydrogen, halogen, COOH, CH2COOH, lower alkyl groups having from 1 to about 4 carbon …
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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 August 29, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 29, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 2013.
- 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.