Chalking

On coating systems, the problem is characterised by white to greyish discolouration, this is referred to as ‘’chalking’’. It seems as if the intensity of the colour disappears. This can, for example, be evident as stains and markings. The coating is severely damaged by UV radiation.

You know the phenomenon with the red car; it eventually changes colour to a dull pink. This occurs on roofs and facades with high pigment colours, blue, red, yellow and anthracite and is usually due to environmental factors, such as UV radiation, excessive contamination and poor maintenance. Treatment with osmosis water can also result in damage. Osmosis is actually water in its purest form separated from additives such as lime, etc. This can have a negative effect on coated facade parts and result in an oxide layer.

What risk do you run?

The emerging corrosion damages the coating. This results in a dull layer on top of the paint. This dull layer becomes increasingly thicker if no remedial action is taken. The aging then becomes evident increasingly deeper into the paint, also often deeper than the scratches. Eventually small cracks appear in the paint, clearly visible as the Craquelé effect. If you do not treat these parts in time, the coating will become so damaged that it will have to be resprayed.

Where does this occur?

On high pigment colours, red, green, blue, yellow. On coatings that are not or are poorly maintained and that are not or do not remain UV-resistant.

Can it be prevented?

Chalking can, in many cases, be minimized and/or prevented by performing correct and periodic maintenance. Modern-day paint systems continue to be improved, and chalking is thus less evident than it was before.