Process for isolating polycarbonates_with co2 under pressure
CA 2069721 A1 · Owner: Bayer Aktiengesellschaft · Inventors: Paul, Hanns-Ingolf; Herrig, Wolfgang; Treckmann, Rolf
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Mo-3738, LeA 28,369, A PROCESS FOR ISOLATING POLYCARBONATES ABSTRACT OF THE DISCLOSURE, A continuous process for the isolation of polycarbonates from a solution of polycarbonate in methylene chloride at temperatures of 30 to 80°C is disclosed. The process which yields polycarbonate in powder form having residual solvent content of less than 5% by weight, is characterized in that it entails the following steps:, a) obtaining a solution of polycarbonate in methylene chloride containing 10 to 40 percent polycarbonate said, percent being relative to the total weight of the polycarbonate solution, b) mixing into said solution under pressures of 10 to 50 bar and at temperaturesof 30 to 50°C 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 May 27, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 27, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2014.
- 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
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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.