Cracking

Defect of a coating film resulting in breaks on its surface and/or in depth. It may be caused by:
– movements of the substrate that the coating film cannot stand;
– excess of hardening agents resulting in too fast drying and/or too brittle dry film;
– solvents still present in UV coatings when they are passed under UV lamps for immediate curing;
– improper coating system (failure to observe the drying times or use of coatings other than those recommended).