Process for continuously producing an aromatic carbonate
CA 2041646 C · Owner: Tojo, Masahiro · Inventors: Kawamura, Mamoru; Tojo, Masahiro; Fukuoka, Shinsuke
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a process for producing an aromatic carbonate or aromatic carbonate mixture by a transesterification reaction between a starting material, selected from a dialkyl carbonate an alkyl aryl, carbonate and a mixture thereof and a reactant selected from an aromatic hydroxy compound, an alkyl aryl carbonate and a mixture thereof, wherein the starting material and the reactant are continuously fed to a continuous multi-stage distillation column to effect a transesterification reaction therebetween in the presence of a catalyst in the distillation column while continuously withdrawing the produced aromatic carbonate or aromatic carbonate mixture as a high boiling point product in a …
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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 December 28, 1990 and granted June 15, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 28, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 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.