Graffiti has become increasingly common in the exterior of building and construction, especially in urban areas. It is, however, unpleasant, and imposes huge costs for its removal. Apart from the economic aspects, interaction of graffiti with substrates, as well as removal procedures endanger the lifetime of historical buildings. For example, post-graffiti actions may result in solvent penetration and in the modification or degradation of the underlying material, which are unacceptable side effects for surfaces of cultural or historical relevance Therefore, developing coatings with anti-graffiti properties has been the focus for many years. Wax or micro-wax coatings (treatments that are removed with the paint) and polyurethane substances (permanent treatments) have kept graffiti painters at bay for years. However, such conventional anti-graffiti products have not solved the problem altogether due to certain drawbacks, including their limited durability. Currently, one of the main challenges in the anti-graffiti coating industry is to find efficient coating materials that have good capabilities in preventing the paint from interacting or combining chemically with air pollution, which renders cleaning more difficult.
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