Argon purification
CA 2004263 C · Owner: Corduan, Horst · Inventors: Corduan, Horst; Rohde, Wilhelm
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure A process and apparatus for air separation by low temperature rectification are described in which argon is obtained exclusively by rectification. A crude argon column (24) is equipped with at least 150 theoretical plates in the form of low pressure drop packing so that in it, a, substantially complete separation of the oxygen is possible e.g. less than about 10 ppm, preferably less than 1 ppm oxygen.
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
- Filed November 30, 1989 and granted February 1, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 30, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 30, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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.