Process of producing isopropylnaphthols
CA 2003780 C · Owner: Ishibashi, Masayasu · Inventors: Taniguchi, Katsuo; Tanaka, Michio; Ishibashi, Masayasu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a process of producing isopropylnaphthols by oxidizing diisopropylnaphthalenes with molecular oxygen in a liquid phase to form a reaction mixture which contains therein diisopropylnaphthalene monohydroperoxides and then decomposing the monohydroperoxides with acids to isopropylnaphthols. An organic layer is separated from the reaction mixture lower, aliphatic alcohols of 1-4 carbons are added to the organic layer and the diisopropylnaphthalenes are crystallized while allowing the diisopropylnaphthalene monohydroperoxides to remain dissolved in the lower aliphatic alcohols, thereby to separate the mono-hydroperoxides from the diisopropylnaphthalenes. The isopropylnaphthols may …
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 24, 1989 and granted September 14, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 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.