Membrane
CA 1269485 C · Owner: Hendy, Brian N. · Inventors: Hendy, Brian N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
MEMBRANE", In a sulphonated aromatic polymer contains repeating units (Ar-Y) (where Y is SO2 and/or CO) at least half of, groups Ar contain a group SO3 M and M is 1/m of a polyvalent metal cation in at least 80% of such groups SO3 M. The polyvalent cation compound is formed by heating the corresponding sulphonic acid or monovalent cation compound with a salt of a polyvalent metal. The polymer is useful as a membane and the polyvalent metal salt addition and/or the heat treatment may be applied to polymer in membrane form.
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
- Granted May 22, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 22, 2007.
- 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.