Patent No. U.S. 7,736,745 B2
Hontek Corporation has been granted a patent for a solid and liquid erosion resistant article comprised of an airfoil shaped substrate having a leading edge surface exposed in use to high speed impingement of liquid and/or solid particles, the leading edge surface covered with a protective coating comprised of a matte topcoat layer comprised of a polyurethane or polyurea composition forming a coating disposed on the leading edge surface having a tensile strength greater than 1000 psi (70 kg/cm2), an elongation at break greater than 400%, a tensile set of less than 150%, and a Shore A hardness of 44A to 95A as measured at 68° F and having a matte finish as measured according to ASTM D 523-89 (1999) with an 85 degree surface gloss less than 15, wherein the polyurethane or polyurea coating composition is selected from the group consisting of a water dispersion of a pre-reacted polyurethane and a polyisocyanate or an isocyanate-terminated prepolymer cured with a curing agent selected from a group consisting of an aldimine, a ketimine, a polyaspartic ester and mixtures thereof and an optional cocuring agent selected from the group consisting of a polyamine, a polyol and mixtures thereof.