Membrane from polyphenylsulfone (radel-r)
CA 2096276 A1 · Owner: Dal-Cin, Mauro · Inventors: Tweddle, Thomas A.; Dal-Cin, Mauro; Tam, Chung M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In general the pore size of polysulfone, ultrafiltration membranes is increased by the addition of polyvinylpyrrolidone to the casting solution used to form the membranes. It has been found that a polyphenylsulfone and polyvinylpyrrolidone mixture can be used to produce an ultrafiltration membrane having relatively high permeability in the small pore size range, e.g. less than 2 mn.
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 14, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 14, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 14, 2015.
- 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.