Biobleaching process
CA 2044100 A1 · Owner: Senior, David John · Inventors: Du Manoir, John R.; Senior, David John; Hamilton, Janice
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
ICICA 794, ABSTRACT, "Biobleaching Process" A process for the production of a bleached lignocellulosic material is provided which comprises the biological treatment of a chemical pulp with xylanase followed by a chlorination stage conducted with chlorine and chlorine dioxide. The chlorination stage is characterized by the timing of addition of the chlorine prior to the addition of the chlorine dioxide. A process to produce bleached pulp at a lower chemical consumption and cost results.
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 June 7, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 7, 2013.
- 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.