Method of using aldehyde-functionalized polymers to enhance paper machine dewatering
CA 2551160 C · Owner: Nalco Company · Inventors: St. John, Michael R.; Zagala, Angela P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of enhancing the dewatering of a paper sheet on a paper machine comprising adding to the paper sheet about 0.05 lb/ton to about 15 lb/ton based on dry fiber, of one or more aldehyde functionalized polymers comprising amino or amido groups wherein at least about 15 mole percent of the amino or amido groups are functionalized by reacting with one or more aldehydes and wherein the aldehyde functionalized polymers have a molecular weight of at least about 100,000.
Read the whole patent
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 January 21, 2005 and granted June 16, 2015. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 21, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.