Expired Canadian patentCanada
Treatment of waste liquor from pulp production
CA 958159 A · Owner: Sonoco Products Company · Inventors: Sheeley, Donald R.; Biggs, William A. (Jr.); Cook, William R.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead 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 November 26, 1974. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 26, 1991.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedNovember 26, 1974
Term endedNovember 26, 1991
Patent numberCA 958159 A
Classification (IPC)D21C11/00
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.