| abstract |
There is disclosed a chrome-free, water-reducible coating composition for application to, and heat curing on, a substrate for providing corrosion protection thereto, said composition comprising, including the aqueous medium: (A) aqueous medium; (B) 1 to 30 weight percent, basis total composition weight, of high-boiling organic liquid;( C ) from 10 to 37, weight percent particulate metal, basis total composition weight; (D) 0.05 to 2 weight percent, basis total composition weight, of thickener; and (E) silane binding agent contributing from 3 to 23 weight percent of the total composition weight, and uses and preparations thereof. The deposited coating film is corrosion-resistant and for coated articles which are threaded, e.g., steel fasteners, the coating provides a non-thread-filling coating. The coating composition contains particulate metal, such as particulate zinc or aluminum. Although substituents can be separately packaged, the composition is virtually always a one-package coating composition. The composition contains water-reducible organofunctional silane, particularly an epoxy functional silane, as a binding agent. The composition has highly desirable, extended shelf life. The composition can be easily applied in the usual manner, such as dip-drain or dip-spin technique, and readily cures at elevated temperature. |