High activity staged reactor process
CA 2199078 C · Owner: Spriggs, Thomas Edward · Inventors: Tilston, Michael William; Spriggs, Thomas Edward
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process comprising contacting ethylene and at least one alpha-olefin comonomer having 3 to 8 carbon atoms with a transition metal based catalyst system in two fluidized bed reactors connected in series in the gas phase, under polymerization conditions with the provisos, that:, (a) the first reactor is operated at a temperature at or above the dew point of the mixture of monomers, but no higher than about 5 degrees C above said dew point;, (b) the mixture of ethylene copolymer matrix and active catalyst formed in the first reactor in the series is transferred to the second reactor in the series;, (c) other than the active catalyst referred to in proviso (b) no, additional catalyst is …
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 March 4, 1997 and granted November 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 4, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 4, 2019.
- 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.