Microporous membrane, method of manufacture, and method of use
CA 2086759 C · Owner: Degen, Peter John · Inventors: Gsell, Thomas C.; Degen, Peter John; Chambers, Jeffrey K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Microporous membranes having positive zeta potentials in alkaline pH are provided by radiation grafting diallyldimethylammonium dimethyl ammonium chloride to the surfaces of a microporous, polyamide membrane using ionizing radiation. The membranes have particular use in microelectronics manufacture where quick rinse up times with ultrapure water are required.
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 May 14, 1992 and granted December 16, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 14, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 14, 2014.
- 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.