Polyamide of disulfonated diamine and permselective membrane thereof
CA 1203941 A · Owner: E. I. Du Pont De Nemours And Company · Inventors: Christell, Lance A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aromatic polyamides which include units based on disulfonated aromatic diamines, the sulfonate groups being present as sulfonic acid groups or alkali metal, alkaline earth metal, transition metal aluminum, ammonium or lower alkyl quaternary ammonium salts thereof, are provided. Permselective membranes fabricated from such polyamides are also provided. The membranes are suitable for reverse osmosis especially for purification of water.
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
- Granted April 29, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 29, 2003.
- 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.