Expired Canadian patentCanada
Composition and process for preventing or restoring lost circulation
CA 722575 A · Owner: Bert Borcherdt · Inventors: Bert Borcherdt
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 30, 1965. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 30, 1982.
- 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 30, 1965
Term endedNovember 30, 1982
Patent numberCA 722575 A
Classification (IPC)C09K3/00 +2 more
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.