Paint Primer Layers Contamination

Primer-coating contamination forms when zinc-rich and epoxy-based layers degrade on metal surfaces after environmental exposure, creating adhesive buildup that bonds tightly to substrate. Unlike rust, which flakes loosely, this contamination exhibits sticky resilience and uneven thickness, so it distinguishes by requiring targeted removal to avoid surface scarring. On steel, adhesion persists strongly while on aluminum and galvanized metal, peeling occurs faster because of weaker interfacial links, yet challenges arise from potential heat-induced cracking during cleaning. Laser cleaning succeeds so because focused pulses vaporize coating selectively, preserving underlying material integrity.