Process for producing 1,4-butanediol and tetrahydrofuran
CA 2030999 C · Owner: Suzuki, Sadakatsu · Inventors: Ichiki, Tatsumi; Ueno, Hiroshi; Suzuki, Sadakatsu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is disclosed a process for the production of 1,4-butanediol and tetrahydrofuran by the catalytic hydrogenation in the gas phase of .gamma.-butyrolactone using a solid catalyst comprising copper and silicon copper, chromium, and manganese or copper chromium, manganese and, barium.
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 28, 1990 and granted January 1, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 28, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 28, 2012.
- 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.