Pulping process
CA 1232109 A · Owner: Kauppi, Peter K. · Inventors: Kauppi, Peter K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention is concerned with an improved pulping process for producing high yield pulps from woody lignocellulosic material wherein the lignocellulosic material is treated with a pulping chemical and mechanically defibrated. The improvement comprises pre-treating the lignocellulosic material by impregnating same with a water-miscible loweralkanolamine and ammonium hydroxide so as to cause softening of lignin in the material and to promote fiber separation. As a result, pulping chemical and refining energy consumption as well as vapor and liquid effluent pollution are significantly reduced.
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
- Granted February 2, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 2, 2005.
- 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.