| abstract |
There is disclosed a water-reducible, chrome-free coating composition fornproviding corrosion protection to a substrate, such as a metal substrate. The depositedncoating film is corrosion-resistant and, for coated articles which are threaded, e.g., steelnfasteners, the coating provides a non-thread-filling coating. The coating compositionncontains particulate metal, such as particulate zinc or aluminum. Although substituentsncan be separately packaged, the composition is virtually always a one-package coatingncomposition. The composition is water-based, while also containing low-boiling organicnliquid. The composition also contains water-reducible organofunctional silane,nparticularly an epoxy functional silane, as a binding agent. The composition has highlyndesirable, extended shelf life. The composition can be easily applied in usual manner,nsuch as dip-drain or dip-spin technique, and readily cures at elevated temperature. |