Chromium-free impregnated activated universal respirator carbon for adsorption of toxic gases and/or vapors
CA 2124192 C · Owner: Cobes, John W. Iii · Inventors: Knebel, William J.; Cobes, John W. Iii; Doughty, David T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Impregnated activated carbon adsorbents for the removal of toxic materials from gas streams are used in a variety of respiration and collective filter applications. The impregnated activated carbon adsorbents of the present invention remain effective in removing toxic gases and/or vapors in industrial and other applications and , are free of chromium and its potential health hazards. Generally, these activated carbons are comprised of an activated carbon adsorbent impregnated so as to result in an activated carbon generally containing up to 10 % molybdenum and up to 10 % sulfate, 0 to 20 % copper, 0 to 20 % zinc optionally, supplemented according to the desired characteristics with …
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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
- Filed November 24, 1992 and granted February 1, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 2014.
- 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.