US Patent 9206320 Matte-appearance powder coating compositions with chemical agent resistance

Matte-appearance chemical-agent-resistant powder coating compositions are described. In embodiments, powder coating compositions comprise a resin component, a polyisocyanate-containing uretdione cross-linking agent, catalyst, and flattening agent. The resin component may comprise a hydroxyl-containing resin and a hydroxyl-containing halogenated copolymer resin. Catalyzed cross-linking of the uretdione isocyanate groups and resins of the resin component during curing preferably yields a finished-form film with low levels of gloss and sheen and chemical-agent resistance.