Wet-strength finishing agents for paper
CA 2447136 A1 · Owner: Basf Aktiengesellschaft · Inventors: Wendker, Martin; Frenzel, Stefan; Boettcher, Claus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to wet-strength finishing agents for paper containing , a) between 1 and 99.9 wt. % of a water-soluble polamidoamine which is crosslinked with an epihalohydrin, and b) between 0.1 and 20 wt. % of at least one other cationic polymer. The invention also relates to a method for producing paper having increased wet-strength, and to the use of said wet-strength finishing agents as additives to the paper stock during the production of paper.
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 May 29, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 29, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 29, 2024.
- 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.