Allophanate group-containing polyisocyanates having improved compatability with aldimines

Abstract From the Canadian patent

The present invention relates to coating compositions containing a) aldimines and, b) polyisocyanates which i) contain 2 to 35 % by weight of allophanate groups based, on the weight of the polyisocyanates ii) have a viscosity of less than 3000 mPa~s at 25°C when measured at a solids content of 100%, iii) are based on the reaction products of aliphatic polyisocyanates with, 1) 10 to 90 mole percent of monohydroxy compounds and, 2) 10 to 90 mole percent of polyhydric alcohols wherein the mole percentages of 1) and 2) add up to 100 and the percentages are based on the total moles of monohydroxy compounds 1) and polyhydric alcohols 2) and iv) contain less than 10 mole percent of urethane groups …