Process for the preparation of polyisocyanates with biuret structure
CA 1248544 A · Owner: Bayer Aktiengesellschaft · Inventors: Pedain, Josef; Woynar, Helmut; Konig, Klaus
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 process for the preparation of polyisocyanates which have a biuret structure by reacting excess quantities of aliphatic diisocyanates with biuretizing agents at elevated temperature, characterized in that the biuretizing agent contains, a) .alpha..alpha..alpha.-trisubstituted acetic acids which do not contain isocyanate-reactive groups apart from the carboxyl group, and optionally, b) water wherein the molar ratio of biuretizing components a) to b) is within the range of from 1:0 to 1:2.5.
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
- Granted January 10, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 10, 2006.
- 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.