With contact angles smaller than 90°, the surface is wetted at least to a small extent. This state is still described as hydrophilic. bezeichnet. With a contact angle >90°, the cohesion in the drop of liquid is in any case greater than the adhesion on the surface. This is a hydrophobic behaviour. By means of plasma polymerisation, coats can be generated which repel the water to a much higher degree than that. Drops of liquid on the surface retain their spherical shape which is flattened not in consequence of wetting but simply because of gravitation. This type of surface is referred to as super-hydrophobic or ultra-hydrophobic.