Mouldings based on pyrogenic silicon dioxide
CA 2253952 A1 · Owner: Degussa-Huls Aktiengesellschaft · Inventors: Krause, Helmfried; Feuer, Oliver; Panster, Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Mouldings based on pyrogenic silicon dioxide with a pore volume of 0.5 to 1.8 ml/g are prepared by homogenising pyrogenic silicon dioxide with methylhydroxyethyl cellulose, wax and polyethylene glycol with the addition of water, which then is subject to a compounding and shaping process, and is extruded. The extrudant is dried at a temperature of 70 to 150°C, and conditioned for a period of 30 minutes to 10 hours at a temperature of 400 to 1200°C. These mouldings may be used as catalysts or as catalyst supports, for the preparation of vinyl acetate monomer the, hydration of ethylene and the hydration of propylene.
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 12, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 12, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 12, 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.