Expired Canadian patentCanada
Process for the production of low viscosity water-soluble cellulose ethers
CA 839258 A · Owner: Kalle Aktiengesellschaft · Inventors: Siegfried Janocha; Hans Macholdt
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 April 14, 1970. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 14, 1987.
- 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—
GrantedApril 14, 1970
Term endedApril 14, 1987
Patent numberCA 839258 A
Classification (IPC)C08B11/14 +1 more
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.