Process for obtaining bleached vegetal pulps
CA 2023809 C · Owner: Atochem · Inventors: Devic, Michel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns the production of bleached dried plant pulp, in which bleaching by hydrogen peroxide takes place at the same time as drying by vaporization of water from the pulp by means of a dry gas atmosphere circulating in contact with the pulp. This process does not have the same disadvantages as existing processes simplifies operational steps to obtain dry bleached pulp, and produces pulp with a high degree of brightness for the technical field concerned.
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 August 22, 1990 and granted July 22, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 22, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 22, 2012.
- 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.