Expired Canadian patentCanada
Prevention of vacuum collapse in flexible containers
CA 1237391 A · Owner: The Procter & Gamble Company · Inventors: Letton, James C.; Robinson, Melzie L.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Vacuum collapse in packages containing oxygen-absorbing compositions is prevented by incorporating certain antioxidants into the compositions.
Read 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 31, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 31, 2005.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJanuary 3, 1985
GrantedMay 31, 1988
Term endedMay 31, 2005
Patent numberCA 1237391 A
Classification (IPC)B65D81/00 +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.