Method for rapid ozone bleaching of wood pulp
CA 2132165 A1 · Owner: Beloit Technologies, Inc. · Inventors: Shackford, Lewis D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for rapid bleaching of high consistency wood pulp using ozone gas provides for generating ozone in a carrier gas at a concentration of five percent to fifteen percent by weight, introducing the ozone in its carrier gas together with the wood pulp into a bleaching reactor at a pressure of more than one atmosphere retaining the pulp and ozone gas in the bleaching reactor for a required bleaching time, and discharging the bleached pulp to a receiving vessel for further processing.
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 September 15, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 15, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 15, 2016.
- 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.