Ion-conducting membrane for fuel cell
CA 2337860 A1 · Owner: Dais Analytic Corporation · Inventors: Sheikh-Ali, Bashir Musse; Wnek, Gary Edmund
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Ion-conducting membranes for fuel cells are disclosed. The membrane is composed of a hydrogenated and sulfonated statistical copolymer of styrene and butadiene. A preferred membrane is obtained by hydrogenating a copolymer of styrene and butadiene to obtain less than five percent residual unsaturation then sulfonating the polymer with an acetyl sulfate sulfonation agent to a level of at least 30 mo1 percent sulfonate.
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, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 28, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2021.
- 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.