Osmotic Blisters in Coatings and Adhesives

摘要

Blistering is one of the main causes of the failure of heavy industrial coatings and of decorative coatings on polyester laminates. When one sees blisters forming, the immediate thought is generally that this is either due to poor chemical resistance of the coating or to poor adhesion at the interface. However, the driving mechanism is the solubiliza-tion of materials, water diffusing into the coatings to equilibrate the concentration, and then water collecting at the interface to initiate and grow delamination.