Glyoxalated polyacrylamide compositions
CA 2498021 C · Owner: Saddler, Lakeisha · Inventors: Johnston, James; Townsend, David; Jenkins, Donald
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for making a storage-stable glyoxalated polyacrylamide composition suitable for use as a strengthening agent for paper in which the glyoxal is added to the base polyacrylamide polymer in two portions and a scavenger for aldehyde groups is used. Aldehyde scavengers which are adducts of choline or a choline salt and an optionally substituted acrylamide monomer can be used to stabilize glyoxalated polyacrylamide compositions and to provide supplementary cationic charges for the polymer backbone. Compositions comprising a blend of a storage-stable glyoxalated polyacrylamide and a polymeric paper strengthening agent can be used to enhance the strength of paper particularly the wet …
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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 February 23, 2005 and granted November 12, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 23, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
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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.