Polyvinylidene fluoride membrane
CA 2082511 C · Owner: Lee, Matthew B. · Inventors: Beck, Thomas W.; Grant, Richard D.; Lee, Matthew B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of making a porous polymeric material by heating a mixture comprising polyvinylidene fluoride and a solvent system initially comprising a first component that is a latent solvent far polyvinylidene fluoride and a second component that is a non-solvent for polyvinylidene fluoride wherein, at elevated temperature, polyvinylidene fluoride dissolves in the solvent system to provide an optically clear solution. The solution is then rapidly cooled so that nonequilibrium liquid-liquid phase separation takes place to form a continuous polymer rich phase and a continuous polymer lean phase with the two phases being intermingled in the form of bicontinuous matrix of large interfacial area …
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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 May 9, 1991 and granted September 10, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 9, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 9, 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.