(per) fluoropolyether carboxylic acids and use thereof for the oleo-repellent paper sizing
CA 2469242 C · Owner: Russo, Antonio · Inventors: Russo, Antonio; Visca, Mario; Tonelli, Claudio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Carboxylic acids comprising perfluoropolyether chains of for- mula: T1-CFW1-O-Rf-CFW2-T2 (I) wherein T1 T2, equal to or different from each other are selected from the group formed of -CH2-B-Y- (COOH) n -CH (CF3} O- Y (COOH) n, -F, -CF3, -C2F5 - (C2F4} C1, wherein B = -O- or -S-; y - Cl-C20 alkylene chain n = 1-4; with the proviso that at least one of the two end groups T1 T2 be -CH2-B-Y-(COOH)n, -CH(CF3)O-Y(COOH)n; W1 W2, equal to or different from each other are -F or -CF3; Rf is a (per)fluoropolyoxyalkylene chain formed of one or more repeating units statistically distributed along the chain having a number average molecular weight in the range 500-10,000.
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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 31, 2004 and granted July 24, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 31, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 31, 2026.
- 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
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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.