Overview

Chalking effects on coated surfaces generally depend on the composition of the coating (binder, pigment, extender, additives, pigment volume concentration), the surface finish, the application method and the weathering conditions the coating is exposed to. The standard specifies a method by which the degree of chalking of coloured and non-coloured paint coatings is determined. The swollen gelatine side of a piece of special photographic paper is placed on the coating under test; the paper is pressed down by a test facility. In this process, exposed, pigment particles which are no longer bound by the binder are absorbed by the gelatine layer. The chalking impression which appears on the gelatine layer is assessed visually and assigned to a degree of chalking. The Committee responsible for this standard is NA 002-00-07 AA "Allgemeine Prüfverfahren für Beschichtungsstoffe und Beschichtungen" ("General test methods for coating materials and coatings") at DIN.

Document: references other documents

Responsible national committee

NA 002-00-07 AA - General test methods for coating materials and coatings