Expired Canadian patentCanada
Protective atmosphere process for annealing and/or hardening ferrous metals
CA 1268690 C · Owner: Berger, Kerry R. · Inventors: Bannos, Thomas S.; Shay, Robert H.; Berger, Kerry R.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for heating steel under atmosphere for annealing or hardening wherein the atmosphere is generated by injecting a mixture of dimethyl ether and nitrogen into the furnace.
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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 8, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 8, 2007.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 9, 1986
GrantedMay 8, 1990
Term endedMay 8, 2007
Patent numberCA 1268690 C
Classification (IPC)C21D1/61 +2 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.