Dirt-repellent Surfaces

Dirt-repellent Surfaces for Paints/Lacquers

Contamination of surfaces: Insects as test objects
© Fraunhofer IFAM
Contamination of surfaces: Insects as test objects
© Fraunhofer IFAM
Assessment of the cleanability of a coating surface

Dirt-repellent and easy-to-clean coatings have been used for many years, for example for sanitary products and glass. The priority here is to reduce the cleaning costs and amount of cleaning work involved.

In the car and aircraft manufacturing industries the main focus for dirt-repellent surfaces is functionality preservation and easy removal of dirt and contamination from components.


The specialists at Fraunhofer IFAM are developing so-called "easy-to-clean coatings" using the following approaches:

  • Hydrophobic surfaces with poor wetting for water which markedly reduce the contact between dirt and the surface. This means easier cleaning and less contamination of surfaces.
  • Superhydrophobic surfaces with additional micro-nanostructuring can cause dirt to fall off the surface. The best known example here is the "Lotus effect".
  • Hydrophilic, photocatalytic surfaces with good water wetting which facilitate dirt removal from the surface. There is also decomposition of organic contaminants by photocatalytic degradation on the surface.
  • Hydrophilic/oleophobic surfaces from which oily contaminants can be removed with pure water.

Fraunhofer IFAM studies the tendency of surfaces to become dirty and the ease of cleaning those surfaces. Self-developed test methods are employed here, following defined contamination with insects or dirt particles.