| 摘要 |
Photoactivatable water born coating composition comprising a) a (meth)acryloyl-functional polyurethane dispersion, with the (meth)acryloyl-functional polyurethane comprising 5 to 18 wt. % of alkylene oxide groups while the (meth)acryloyl functionality is in the range of 2 to 40, and b) a UV-initiator. Preferably, the (meth)acryloyl-functional polyurethane comprises 8 to 18 wt. % of alkylene oxide groups. More preferably, the coating composition comprises a reactive diluent. The (meth)acryloyl-functional polyurethane is obtainable by reaction of: a) at least one organic polyisocyanate, b) optionally, at least one organic compound containing at least two isocyanate-reactive groups and having a number average molecular weight in the range of 400 to 6,000, c) at least one isocyanate-reactive and/or isocyanate-functional compound bearing non-ionic dispersing groups, d) at least one isocyanate-reactive (meth)acryloyl-functional compound, e) optionally, at least one active hydrogen-containing chain extender, and f) optionally, at least one active hydrogen-containing compound bearing ionic groups. The water born coating composition is especially suitable for application as a clear coat. |
