Polyisocyanates blocked with ch-acidic esters and stabilized against thermal yellowing
CA 2266250 A1 · Owner: Kuttner, Wolfram · Inventors: Konig, Eberhard; Kobusch, Claus; Kuttner, Wolfram
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 a stabilized aliphatic and/or, cycloaliphatic, blocked polyisocyanates which have i) isocyanate groups blocked with CH-acidic esters ii) a content of blocked isocyanate groups (calculated as NCO MW 42) of, 5 to 20, preferably 7 to 15 wt.% based on the solids content of the, blocked polyisocyanate and iii) a content of formaldehyde of 0.1 to 5 wt.% based on the solids content, of the blocked polyisocyanate. The present invention also related to a process for the preparation of these stabilized, blocked polyisocyanates and to their use in one-component polyurethane stoving compositions, which may be cured at relatively low stoving temperature of about 100°C, …
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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 March 22, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 22, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 22, 2021.
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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.