Method of producing paper, paperboard and cardboard
CA 2382672 A1 · Owner: Linhart, Friedrich · Inventors: Mohr, Bernhard; Fehringer, Dietrich; Dirks, Bernd
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method of producing paper paperboard and cardboard , by dewatering a paper material in the presence of condensation products of basic amino acids and sheet forming. The inventive method especially uses homoand co-condensation products of lysine and the cross-linked condensation products obtained therefrom by reaction with cross-linking agents in an amount of from 0.01 to 5 wt.- % based on the dry paper material to increase the dry and wet strength and the absorbency of paper. These materials are also used to fixate anionic dyes and interfering substances in the paper to increase the , dewatering rate and the retention and the efficacy of synthetic anionic and …
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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 16, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 16, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 16, 2022.
- 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.