Anti-graffiti paints: what are they and how do they work?

Date: 10/03/2022
Categories: Coatings

Vandalism is a widespread phenomenon in almost all urban settings, where graffiti, writings, and tags often deface building façades, street furniture, and public transport. Anti-graffiti paint is one solution to counteract and discourage them. In this article, we will look at what anti-graffiti coatings are, how they work, and where to apply them.

Anti-graffiti paints are special coatings designed to protect public buildings and street furniture against graffiti, making it easier to clean their surfaces without having to repaint them.

Anti-graffiti coatings are normally available in a wide range of colours and finishes, including transparent and metallic ones. Both liquid and powder products are available. The latter, be they polyester or polyurethane, are generally the most common ones.

They can be divided into two main types:

  • Sacrificial anti-graffiti coatings, called this way because they are applied and then “sacrificed”, i.e. removed together with the graffiti.
  • Permanent anti-graffiti coatings, which do not degrade when the graffiti is removed.

The type of paint to be applied depends on the substrate and the desired effect. However, permanent anti-graffiti coatings are more popular, as they allow graffiti to be removed with a commonly used solvent without damaging the underlying surface or compromising the coating. This means that permanent anti-graffiti paints do not have to be reapplied later, which optimises application times and costs.

How anti-graffiti paints work

When applied on an object to be protected, an anti-graffiti coating creates a special, highly cross-linked film, which prevents the chemicals that normally make up sprays and permanent markers from penetrating the paint and thus staining the surface beneath.

Whereas in the past the cross-linking of these products made them inelastic and therefore not suitable for painting components that had to undergo post-forming, technological progress has now made anti-graffiti coatings ideal also for surfaces that need further processing, without compromising their functionality.

Moreover, anti-graffiti paints do not ensure only excellent chemical resistance to commonly used solvents such as xylene, acetone, turpentine, and methyl ethyl ketone, but also good corrosion protection.

The test method for determining whether a certain product can be actually considered a permanent anti-graffiti coating is regulated in the UNI 11246:2007 standard, “Aluminium and aluminium alloys - Evaluating procedure for permanent anti-graffiti products”. In particular, anti-graffiti paints must guarantee at least 10 cycles of soiling and subsequent cleaning without the coating and its chemical and physical properties being affected.

How and on which materials to apply anti-graffiti paints

Anti-graffiti paints can be used on many surfaces, including metal, concrete, stone, and marble.

Anti-graffiti coatings, which can be easily applied with brushes or rollers or by spraying, especially in industrial applications, are the ideal protective solution for any surface located in easily accessible public places and usually subject to vandalism, including for example:

  • railway and underground stations;
  • public transport wagons;
  • street signs and furniture;
  • benches, recreational equipment, and other public park furniture;
  • shutters and fences;
  • monuments and building façades.

To find out more on this subject and get to know the main manufacturers of anti-graffiti paints, you can check out our website and magazines.