Production of supported thin film membranes
CA 2045109 A1 · Owner: Exxon Research And Engineering Company · Inventors: Feimer, Joseph Louis; Koenitzer, Bernd Alfred
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Supported thin film membranes of polyurethane, polyurea/urethane, polyurea/polyurethane alloy blends are prepared by depositing a solution of the appropriate polymer on a microporous hydrophobic support. The solution wets but does not soak through the hydrophobic support because the amounts and ratios of solvents and surfactant used to produce the solution have been adjusted to produce a solution having optimum coating properties (for example, surface tension solvency, viscosity). The polymer solution is optionally aged at least 1 day prior to being coated on the microporous support.
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 June 20, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 20, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 20, 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.