7. Coating Failures

7.4 Types of Failures

Types of Failures

Coating failures can be divided into the following categories

  1. Formulation related failures

  2. Substrate related failures

  3. Design related failures

  4. Adhesion related failures

  5. Application related failures

1. Formulation related failures

These types of failures arise from the improper formulations such as pigment/binder ratio, volume of solvent, additives in excess or deficient amounts. Four types of failures as described below belong to this category.

  1. Chalking

  2. Checking

  3. Alligatoring

  4. Cracking and

  5. Mud Cracking

(A) Chalking


A chalky deposit on the surface which can be removed by a slight application of pressure.




The entire coating surface turns into a powder after a period of exposure. The binder disintegrates by the active rays of the sun and leaves residues of pigments on the surface. The process of chalking is accelerated by alternate wet-dry cycles and improper mixing ratio of pigment to binder.

Fortunately, the coating film underneath the chalky surface remains intact. The process is very slow which affords a chance of repair before the damage reaches the substrate.



  • Remove the powder from the surface

  • Apply chalk resistant binders such as acrylics and polyurethanes in a proper ratio with pigments.

  • Do not add more than the recommended quantity of thinners.