| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a binary polyurethane coating composition which improves the solvent resistance and water resistance, exerts a high gloss, reduces haze, extends the pot-life, has a high coating stability and has an appropriate blister- free coating thickness. SOLUTION: A coating composition contains A) from 30 to 90 wt.% aqueous dispersion of a hydroxy-and/or amino-functional resin and (B) 1 to 70 wt.% water-dispersible polyisocyanate mixture having (a) an average isocyanate functional value of at least 2.0, (b) 5.0 to 25.0 wt.%, based on the resin solid component, isocyanate group and (c) 2 to 50 wt.%, based on the resin solid component, ethylene oxide unit incorporated in a polyether chain having an average of 5 to 35 ethylene oxide units. Here, at least 60 mol.% of the polyether chain is linked to two polyisocyanate molecules, each made from at least two diisocyanate molecules, via allophanate groups.</p> |
