Membrane fabrication
CA 2040409 A1 · Owner: Wilkes, John S. · Inventors: Wilkes, John S.; Pacynko, Witold F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
57) Abstract, Process for the fabrication of a hollow fibre asymmetric membrane comprising extruding a polymer dope solution and a coagulating core liquid into a support fluid. The support fluid is usually of a higher density than the polymer solution. The direction of extrusion is generally upwards into the body of the support fluid. Polymer dope solutions comprise polyimides, polysulphones, polyamides and cellulose acetates and the hollow fibres formed are suitable for use in a separation module.
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 September 13, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 13, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 13, 2012.
- 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.