Polyamines and a process for their production
CA 1248546 A · Owner: Bayer Aktiengesellschaft · Inventors: Rasshofer, Werner
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polyamines containing aromatically bound primary amino groups are prepared in a single stage process by hydrolyzing an isocyanate in the presence of a compound containing an amidine and/or guanidine group and a water-miscible, aprotic-dipolar solvent. This hydrolysis is carried out at from 20 to 210°C with the reactants being in substantially homogeneous phase. The isocyanate starting material contains aromatically bound NCO groups and has NCO content of from 0.5 to 40 wt. %. The compound containing amidine and/or guanidine groups functions as a catalyst and is used in a quantity of at least 0.001 parts by weight for every 100 parts by weight of isocyanate. The water-miscible solvent is …
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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
- 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.