DIN CEN/TS 16360 DIN SPEC 91031:2012-10

This document specifies a test method for assessing the discoloration of coatings on wood by tannin staining due to wood extractives. Bleeding of wood extractives can be assessed in two phases, after coating application and after cyclic climate exposure. It is allowed to carry out the assessment only after coating application without additional climate exposure. A qualification of colour differences that can be attributed to bleeding of extractives, low opacity of the coating film or general yellowing in climate exposure is included. This document does not specify values of colour differences that can be tolerated and it is not applicable to staining of knots.