Expired Canadian patentCanada
1-isopropylamino-anthraquinone-5-sulphonic acid, its alkali metal salts and process for the production thereof
CA 888717 A · Owner: Farbenfabriken Bayer Aktiengesellschaft · Inventors: Hans-Samuel Bien; Klaus Wunderlich
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 December 21, 1971. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 21, 1988.
- 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—
GrantedDecember 21, 1971
Term endedDecember 21, 1988
Patent numberCA 888717 A
Classification (IPC)C09B
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.