The Problem of a Peeling-off Coating
When you have the problem of a peeling-off coating, it can be caused by an ineffective combination of two powder coating layers. In order to optimally protect a metal substrate from corrosion, a two-layered coating can be applied. In the case of using a transparent topcoat, you need to take into account that transparent layers do not hold back UV-light.
As UV-light passes through the transparent topcoat, it will get reflected and absorbed by the underlying layer. When, for example, a transparent outdoor durable topcoat (polyester, polyurethane) is applied on an epoxy or epoxy/polyester first layer (non-outdoor durable layer), then the applied topcoat cannot prevent the discolouring and chalking of the underlying painted material. The chalking process will consequently result in a peeling off of the transparent topcoat. Make sure that your outdoor coated objects are painted with the appropriate paint components. Whenever you have questions on this, you can ask Protech Oxyplast.