An ion exchange membrane used for a fuel cell
CA 2124839 C · Owner: Okamoto, Saburo · Inventors: Noaki, Yasuhide; Okamoto, Saburo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides an ion exchange membrane used for a proton exchange membrane type fuel cell comprising a repeating unit represented by the following formula (See Fig. 1) (1), wherein X: is 0, 1 or 2 y is 2 or 3, L and m are positive numbers and L/m is a positive number of 10 or less; and having an electrical conductivity of 0.11 to 0.30 .OMEGA.-1 cm-1 at 25° C a permeability coefficient to hydrogen gas of 9.0 x 10-9 to 24.0 x 10-9 CC cm/(cm~ sec cmHg) at 40° C, a permeability coefficient to oxygen gas of 5.0 x 10-9 to 11.0 x 10-9 CC cm/(cm~ sec cmHg) at 40° C and a water content of more than 100 to 250% by weight. According to the present invention the ion exchange, membrane …
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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 February 25, 1994 and granted October 7, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 25, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 25, 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
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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.