Improved method for making cyclohexanol and cyclohexanone
CA 2295656 C · Owner: E.I. Du Pont De Nemours And Company · Inventors: Ostermaier, John Joseph; Russell, George Crumbaugh Iii
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved method for making cyclohexanone and cyclohexanol from oxidation of cyclohexane in which a polyprotic acid is used to neutralize caustic to prevent oligomerization of cyclohexanone during fractional distillation.
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 August 19, 1998 and granted December 24, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 19, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 19, 2020.
- 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.