Improved chemical pulping process
CA 2271900 A1 · Owner: Habermehl, James · Inventors: Habermehl, James; Burow, Richard Frederick; Elms, Russell Allen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention claims the use of an oxyalkylene-modified organopolysiloxane in combination with, an alkylated sulfonated diphenyloxide surfactant as, chemical pulping additives. These pulping additives surprisingly improve the physical properties of wood pulp and products produced therefrom.
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 May 11, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 11, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 11, 2021.
- 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.