Method of treatment of waste paper of the like
CA 2098092 C · Owner: Mascoma Canada Inc. · Inventors: Yu, Ernest K. C.; Bouchette, Michael P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Method is disclosed of treatment of waste paper or the like at high temperatures in the range of 160°C to about 230°C. The furnish is treated in a digester with or without added chemicals but in the presence of saturated steam. The preferred dwell times are in the range of about 1 minute to about 6 minutes. The treated furnish is then discharged from the digester preferably, but not exclusively, by an explosive discharge. The advance in the art is in an improved de-inking effect reduced consumption of, chemicals and power. Also some furnishes previously unsuitable for re-cycling have been successfully processed by the method of the invention.
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 December 9, 1991 and granted December 16, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 9, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 9, 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.