Stabilized aqueous solutions of unsaturated quaternary ammonium salts
CA 2209769 C · Owner: Legros, Robert · Inventors: Riondel, Alain; Legros, Robert
Overview
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Open the CIPO recordAbstract From the Canadian patent
The invention relates to an stabilized aqueous solution of at least one unsaturated quaternary ammonium salt of the formula: (SEE FIG. I) wherein R1 represents a hydrogen atom or methyl radical R represents a methyl radical or benzyl radical and X is one of Cl, Br, I or -CH3-SO4, the quaternary salts of the formula (I) having been obtained by reaction in the presence of water, from N,N-dimethylaminoethyl (meth)acrylate of the formula (II): (See FIG. II) wherein R1 is as defined above with a quaternizing agent of the formula (III): R-X (III) wherein R and X are as defined above. This aqueous solution contains at least one stabilizer associated with the monomer of the formula (II) and …
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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 July 8, 1997 and granted April 17, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 8, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 8, 2019.
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