There are normally three layers of coatings on a modern automobile: primer, paint, and the clear coat. The primer acts as a base layer for the paint, assisting with adhesion, provides a predictable surface for coating, and provides additional protection for the underlying metal. The paint is the color coat. The clear coat provides a hard "shell" that protects the paint from oxidization, minor scratches, and increases the longevity of the aesthetic benefits of the colored paint. Car paint peeling (delamination) occurs when one or more of these layers lose adhesion with the surface under it. Primer may lose adhesion to the bare metal, paint may lose adhesion to the primer, and the clear coat can lose adhesion to the paint. When this happens, large sections or flakes of paint can slough off the vehicle.
There are two primary causes for car paint peeling: