Expired Canadian patentCanada
Draft tube, direct contact crystallizer
CA 2041676 C · Owner: Praxair Technology, Inc. · Inventors: Cheng, Alan Tat-Yan
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A direct contact crystallizer having a vertically oriented draft tube into which gas or vaporized liquid is injected and through which a crystal slurry is drawn for cooling and agitation.
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 May 2, 1991 and granted July 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 2, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 2, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 2, 1991
GrantedJuly 7, 1998
Term endedMay 2, 2011
Patent numberCA 2041676 C
Classification (IPC)B01D9/02 +2 more
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.