Low monomer polyurethane prepolymer and process therefor
CA 2276523 A1 · Owner: Henkel Kommanditgesellschaft Auf Aktien · Inventors: Omoruyi, Astrid; Kruedenscheidt, Markus; Bolte, Gerd
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a monomer-poor polyurethane prepolymer comprising , free NCO groups. Said prepolymer is produced from polyvalent alcohols and diisocyanates having different reactivity and is characterized by the proportion of the NCO groups of the partially less reactive diisocyanate with respect to the NCO groups of the more reactive diisocyanate the proportion , being greater than 6 to 1. However the inventive prepolymer hardens faster than a known polymer containing primarily more reactive NCO groups. Preferably, TDI is used as partially less reactive diisocyanate and MDI as more reactive diisocyanate. The production of the prepolymers occurs in two stages. The inventive …
Read the whole patent
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 December 18, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 18, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 18, 2019.
- 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
Timeline From CIPO dates
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.