Can a surface treated with silane-based water repellents be painted?
Yes and no – the answer depends both on the type of water-repellent and paint formulation used. With the exception of Protectosil® CHEM-TRETE® 40D, Protectosil® BHN Plus, Protectosil® AQUA-TRETE® SG and Protectosil® ANTIGRAFFITI, all Protectosil® silane-based water repellents are compatible with most resins used in acrylic, epoxy or oil-based paints. A more important issue is the carrier, or solvent, employed in the paint formulation and its ability to “wet-out” and spread the paint evenly over the treated surface. Solvent-based paint formulations (with an alcohol, ketone, toluene, mineral spirit or other solvent carrier) will usually spread readily over silane-treated surfaces. Water-based paint formulations are more difficult, since wet-out depends on the type of surfactant used. Because of variation in paint formulations, substrate conditions and enviromental factors, it is recommended to apply a test section of the paint over the Protectosil® CHEM-TRETE® or Protectosil® AQUA-TRETE®
