TWO-COMPONENT URETHANE COATING SYSTEM

摘要

The present invention contemplates the provision of two-compo-nent urethane coating compositions comprising a first component comprising an organic polyfunctional isocyanate, and a second component comprising an acidic ester of a phosphoric acid, the alcohol portions of said acidic acid being selected from the group consisting of hydrocarbyloxy and hydroxysubstituted hydrocarbyloxy compounds, such compositions providing enhanced corrosion resistance properties as well as improved flame retardency and metal adhesion characteristics over the two-component urethane systems of the prior art. An essential ingredient in the compositions of the invention is a non-Newtonian colloidal disperse system which can be provided with either the first component and/or the second component parts of the compositions of the invention. The non-Newtonian colloidal disperse systems provided in accordance with the present invention comprise (1) solid metal-containing colloidal particles predispersed in (2) a disperse medium of at least one inert organic liquid and (3) as an essential third component at least one member selected from the class consisting of organic compounds which are substantially soluble in said disperse medium, the molecules of said organic compound being characterized by polar substituents and hydrophobic portions. The invention also relates to a method of coating a substrate comprising mixing the foregoing components and depositing the resulting composition on said substrate.