Crosslinked polymeric ammonium salts
CA 2179712 C · Owner: E.I. Du Pont De Nemours And Company · Inventors: Khasat, Nitya Prakash; Figuly, Garret Daniel; Royce, Susan Durkee
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed are novel crosslinked polymeric ammonium salts wherein in said polymeric salt: about 25 % or more of the segments which link ammonium nitrogen atoms are group Y wherein Y is an n-alkylene group or alkyl substituted n-alkylene group wherein said, n-alkylene group has 7 to about 20 carbon atoms; zero to about 75 % of segments which link ammonium nitrogen atoms are group Z wherein Z is a hydrocarbylene radical containing 2 or more carbon atoms said hydrocarbylene radical optionally containing one or more hydroxyl, ether, amino, thioether, keto or silyl groups or heterocyclic rings; and about 25 % or more of the ammonium atoms are secondary ammonium atoms.
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 January 18, 1995 and granted November 27, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 18, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 18, 2017.
- 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.