Valspar Patents Crush Resistant Latex Topcoat for Fiber Cement

April 1, 2013

U.S. 8,202,578 B2
Valspar Sourcing has been granted a patent for a method of making topcoated fiber cement articles comprised of providing an unattached fiber cement board substrate having a first major surface; providing a topcoat coating composition comprised of a multistage latex polymer having a soft stage Tg such that the coating composition will coalesce at a Minimum Film Forming Temperature (MFFT) between approximately 0°C and about 55°C without requiring more than 10% VOCs for acceptable film formation, and a hard stage Tg such that cement board substrates topcoated with the coating composition may be stacked without exhibiting evidence of crush damage; applying the coating composition to at least a portion of the first major surface; drying or otherwise hardening the coating composition to form a crush resistant final topcoat that is color change resistant when exposed outdoors; and wherein the final topcoat has a Crush Resistance value of at least 3 when two face-to-face coated embossed fiber cement board substrates are subjected to a pressure of 6 kg/cm2; and stacking more than two of the thus-coated boards on a pallet or other horizontal supporting surface.