A process for the production of paper
CA 2194680 C · Owner: Nilsson, Lennart · Inventors: Norell, Maria; Nilsson, Lennart
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the production of paper by mixing an aqueous phase comprising white water with cellulose containing fibres and optinal fillers, in a mixing , stage to form an aqueous suspension draining the suspension in the presence of a drainage or retention aid to form a fibre containing sheet or web and white water, and recirculating at least part of the white water to the mixing stage, whereby at least part of the white water is subjected to electrodialysis before the mixing stage.
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 7, 1996 and granted July 17, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 7, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 7, 2018.
- 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.