Patent ID: 9440937
Filing Date: 2016-09-13
CPC Classification: C07D,C08G

Claim Text:
1. A method for preparing polyisocyanates comprising iminooxadiazinedione groups by oligomerization of monomeric di- and/or triisocyanates comprising utilizing a catalyst, wherein the catalyst is a quaternary phosphonium polyfluoride of the formula R 4 P + F − .n(HF), where R are the same or different, optionally branched, aliphatic, aromatic and/or araliphatic C 1 -C 20 residues and optionally two or more substituents R may also form saturated or unsaturated rings with one another and with the phosphorus atom and n can have any values between 0.1 and 20, and wherein the water content of the catalyst added to the isocyanates to be oligomerized does not exceed 1000 ppm.