摘要 |
<p>An aqueous, two component system for coating a substrate includes either a filler incorporated in both components prior to combining the components or an elevated amount of a filler, such as 50% by dry volume, in either component. The filler is preferably calcium carbonate, but may also be selected from titanium dioxide, sand, clay, mica, dolomite, silica, talc, perlite, gypsum, wallastonite, aluminum trihydrate, zinc oxide, barium sulfate, zinc sulfate, and combinations thereof. The first component includes a first polymer containing hydroxyl functional groups or amine functional groups and, optionally, a catalyst, preferably an organotin catalyst. The first polymer is selected from a polyester polyol, an acrylic polyol, a urethane polyol, a polyother polyol, a polyamine, an aldimine, a short oil alkyd, a silicone polyol, a cellulose ester, a vinyl polyol, and combinations thereof and preferably is a polyaspartic ester. The second component includes a second polymer which is polyisocyanate containing isocyanate functional groups. The coating can be applied by applying to the substrate the first component then separately applying the second component shortly thereafter. Alternatively, the components can first be mixed then applied to the substrate as a mixture.</p> |