Process for preparation of resorcinol
CA 2080697 C · Owner: Sumner, Charles E. Jr. · Inventors: Hitch, Brenda J.; Bernard, Bobby L.; Sumner, Charles E. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for preparation of resorcinol bis(hydroxyethyl)ether by first contacting resorcinol with ethylene carbonate in the presence of water and an alkali metal carbonate and then adding a solution of water and an alkali metal hydroxide and then recovering the resorcinol bis(hydroxyethyl)ether by crystallization.
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 April 3, 1991 and granted August 11, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 3, 2013.
- 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.