By coating surfaces with, e.g. lacquers, these can be protected against ambient media and/or their appearance can be changed and/or equipped with various other special functions.
An efficient and inexpensive corrosion protection measure for metallic materials is coating with polymer-based varnishes. These can be liquid systems (aqueous, solvent-based), powder coating systems or UV coatings.
The barrier effect prevents involved media such as oxygen, water or acids from reaching the surface of the substrate. In addition to this barrier effect, further corrosion protection mechanisms can be realized in coating layers, such as:
An essential prerequisite for good corrosion protection of the coatings is, among other things, their adhesion to the substrate, which is tested by means of cross-cutting.
Besides a protective function for the material, another reason for a coating is the adjustment of certain functional surface properties, such as:
- Electrical conductivity
- Dirt-repellent behavior
- Gloss retention of galvanized steel
- Optical properties of surfaces
- Improvement of resistance to abrasion or chemical attack
The development and optimization of coating systems is carried out application-oriented. For example, a highly chemical-resistant coating was developed for use in biogas reactors. In addition to stability and resistance against the aggressive conditions, the sealing effect on concrete played a major role.