Membrane made from multiblock polymer
CA 2096439 A1 · Owner: Schucker, Robert C. · Inventors: Schucker, Robert C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a multi-block polymeric material comprising a first amide acid prepolymer made by combining , A) a diamine with B) a dianhydride or its corresponding tetraacid or diacid-diester in an A/B mole ratio ranging from about 2.0 to 1.05, preferably about 2.0 to 1.1, chain extended with a second different, compatible prepolymer selected from the group of prepolymers comprising A) a dianhydride or its corresponding tetraacid or diacid-diester combined with a monomer selected from B) epoxy, diisocyanate and polyester in an A/B mole ratio ranging from about 2.0 to 1.05, preferably about 2.0 to 1.1. The present invention is also directed to membranes of the above …
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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 November 15, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 15, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 15, 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.
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.