Preparation of caprolactam
CA 2003552 C · Owner: Merger, Franz · Inventors: Fischer, Rolf; Priester, Claus-Ulrich; Merger, Franz
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Caprolactam is prepared by, heating a 6-aminocaproic ester in liquid phase in the presence of water to 230-350°C under superatmospheric pressure in a reaction medium comprising a liquid aromatic hydrocarbon having a boiling point of from 80 to 240°C which is inert under reaction conditions and, isolating caprolactam from the reaction mixture.
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 20, 1989 and granted May 4, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 20, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 20, 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.