The degree of chalking, a measure for the amount of particles exposed by chalking, is determined by the reduction in the intensity of light passing through the adhesive tape after having applied to the coating.
Chalking is the appearance of a loosely adherent fine powder on the surface of a paint coating arising from the degradation of one or more of its constituents (EN DIN ISO 4628).
The chalking tester which measures the chalking resulting from natural or artificial weathering of coatings is based on the analytical principle of nephelometry and the adhesive tape method according to Helmen.
