Catalyst for purifying exhaust gas
CA 2096328 C · Owner: N.E. Chemcat Corporation · Inventors: Shiokawa, Kazuhiko; Itoh, Takashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A catalyst for purifying exhaust gas, comprising a zeolite carrier having a mole ratio of SiO2/Al2O3 of from 20 to 200, and a compound oxide of copper and silicon supported on the carrier. The catalyst has high activity for elimination of nitrogen oxides (NOX) even in the presence of both oxygen and water vapor, and also has excellent durability at high temperatures. The catalyst is therefore effective in eliminating nitrogen oxides from exhaust gases from automobiles, boilers and the like.
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 May 14, 1993 and granted April 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 14, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 14, 2015.
- 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.