Catalyst and process for the preparation of aromatic carbonates
CA 2298654 A1 · Owner: Teijin Limited · Inventors: Yoshisato, Eishin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aromatic carbonates can be prepared economically and efficiently by reacting an aromatic hydroxyl compound with carbon monoxide and oxygen in the presence of a catalyst which comprises a perovskitic composite oxide represented by the following general formula (1): M(1-x)M'xM''Oy (wherein M is a group IIIB metal; x is a number of 0 to 1; M' is a metal having an ionic radius of 0.90 .ANG. or above; M'' is Mn, Cr, Co, Fe, Ni or Cu; and y is a number of 2.5 to 3.5) or formula (1'): L(1-x)L'xL''Oy (wherein L is a group IIA or IVA metal taking a divalent state in the form of an oxide; x is a number of 0 to 1; L' is a metal having an ionic radius of 0.90 .ANG. or above; L'' is a group IVA …
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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 August 4, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 4, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 4, 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.