Transition-metal-catalyzed process for the preparation of sterically hindered n-substituted alkoxyamines
CA 2443064 C · Owner: Ciba Specialty Chemicals Holding Inc. · Inventors: Shum, Sai Ping; Pastor, Stephen Daniel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Sterically hindered N-substituted alkoxyamines are prepared by the transitionmetal-catalyzed decomposition of diazonium salts in the presence of a sterically hindered nitroxyl radical. These compounds are useful as thermal and light stabilizers for a variety of organic substrates.
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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 March 25, 2002 and granted June 14, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 25, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 25, 2024.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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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.