Expired Canadian patentCanada
Method for the removal and recovery of promoter from crude phthalic anhydride made by the vapor phase oxidation of orthoxylene in the presence of promoter
CA 786357 A · Owner: Chemical Process Corporation · Inventors: Robert B. Egbert
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 May 28, 1968. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 28, 1985.
- 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—
GrantedMay 28, 1968
Term endedMay 28, 1985
Patent numberCA 786357 A
Classification (IPC)C07D307/89
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.