Draft tube, direct contact cryogenic crystallizer
CA 2114446 C · Owner: Cheng, Alan T. · Inventors: Cheng, Alan T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A direct contact cryogenic crystallizer having a vertically oriented draft tube into which cryogenic fluid is injected at a high velocity along with warm gas and through which a crystal slurry is drawn for subsequent cooling and agitation for the production of crystals.
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 January 28, 1994 and granted July 27, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2016.
- 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.