Semi-continuous process for the preparation of polyurethane-urea aqueous dispersions
CA 2020785 A1 · Owner: Ruetman, Sven H. · Inventors: Anand, Joginder N.; Ruetman, Sven H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A semi-continuous process for the preparation of polyurethane ionomer or polyurethane-urea ionomer aqueous dispersions which comprises:, 1) forming an isocyanate-terminated ionic prepolymer in a reaction zone A by, contacting (i) an excess of an aliphatic or cycloaliphatic diisocyanate, or mixture of an aliphatic or cycloaliphatic diisocyanate with an aromatic diisocyanate; (ii) an organic polyol, and (iii) a difunctional isocyanate-reactive component containing an ionic group or potential ionic group, with the proviso that where an aromatic, diisocyanate is used the equivalents of, aromatic diisocyanate used are less that the equivalents of the organic polyol and difunctional …
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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 10, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 10, 2012.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.