| 摘要 |
The present invention is directed to a polyisocyanate mixture which i) is prepared from a monomeric starting material containing a) 95 to 100% by weight, based on the weight of a) and b), of an aliphatic diisocyanate having 4 to 18 carbons in the hydrocarbon chain and b) 0 to 5% by weight, based on the weight of a) and b), of a diisocyanate other component a), ii) has an equivalent weight that is at least 30% greater than the average molecular weight of the monomeric starting material and a viscosity of greater than 10,000 to 100,000 mPa.s when determined at 25.degree.C on a sample having a solids content of 100% and containing less than 2% by weight of unreacted diisocyanates a) and b), and iii) contains isocyanurate groups and allophanate groups in a molar ratio of 10:1 to 1:10, wherein the allophanate groups are derived from urethane groups that are the reaction product of starting material i) with 0.01 to 0.6 moles, per mole of starting material i), of a monoalcohol having a molecular weight of up to 2500. The present invention also relates to the use of these polyisocyanate mixtures, optionally in blocked form, as an isocyanate component in one- or two-component coating compositions.
|
