Comparative study of the variation of the hydric properties and aspect of natural stone and brick after the application of 4 types of anti-graffiti

In this article a comparative study of the behaviour of different commercial anti-graffiti on natural stone and brick is presented. 8 different European substrates were selected and 4 commercial anti-graffiti of different chemical nature were applied on these substrates. The variations of their hydric properties and aspect (colour and gloss) with regard to the untreated substrates were later studied in the laboratory. The results obtained permitted to assess the suitability of 4 of the main types of chemical formulations employed to be used as anti-graffiti. This study concludes that the sacrificial anti-graffiti with polymeric paraffins in its composition presents the lowest reductions of the hydric properties of the studied substrates, being also the variations in colour the least perceptible.