Copolymers containing hydroxyl, epoxide and anhydride groups, a process for their production and their use as binders or binder components
CA 2015044 C · Owner: Bayer Aktiengesellschaft · Inventors: Blum, Harald; Pedain, Josef; Wamprecht, Christian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to copolymers which have a weight average molecular weight of about 1,500 to 75,000, are prepared from olefinically unsaturated compounds and contain in chemically bound form, i) about 0.2 to 6.0% by weight of free hydroxyl groups ii) about 1 to 30% by weight of carboxylic anhydride groups (expressed as C4H2O3) and, iii) about 0.4 to 13% by weight of epoxide groups (expressed as C2H2O). The present invention also relates to a process for the production of these copolymers by copolymerizing a mixture of olefinically unsaturated compounds at about 60 to 120°C in the presence of compounds which initiate the polymerization reaction: Finally, the present invention …
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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 April 20, 1990 and granted August 15, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 20, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 20, 2012.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.