Polyfluoro nitrogen-containing organic compounds
CA 2032813 C · Owner: E. I. Du Pont De Nemours And Company · Inventors: Kirchner, Jack R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polyfluoro organic compound having at least one urea linkage derived from: (1) at least one polyisocyanate containing at least three isocyanate groups, (2) at least one fluorochemical compound which contains per molecule (a) a single functional group having one or more Zerewitinoff hydrogen atoms and (b) at least two carbon atoms each of which contains at least two fluorine atoms, and (3) water in an amount sufficient to to react with from about 5% to about 60% of the isocyanate groups.
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 December 20, 1990 and granted September 24, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 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.