Protective paint is used for its protective rather than aesthetic properties. They are different from domestic paints and need to be applied by professional painters. Protective painting is used to prevent corrosion of steel and other metal structures and protect concrete and masonry surfaces. Protective paint should have good adhesion, water and vapour resistance, resistance to impact and chemical attack and capability to withstand the environment for which they were chosen. A typical protective coating system should have a primer, intermediate coat and top coat. The following are some features that each of the coatings should have to make a good protective painting system.

Primer

Before application of a primer, a process known as abrasive blasting is carried out. This roughens and cleans the surface in preparation for the primer. A primer is used to wet the surface and create a base for the intermediate coating. A good primer for protective painting should have good adhesion to the surface. It also needs to be compatible with the intermediate and top coats chosen for protective painting. It may also need to provide corrosion resistance and protection to the surface being painted.

Intermediate coat

Intermediate coating comes after the primer. It can consist of epoxy polyamide among other chemical substances and is used to provide a system thickness build and prevent permeability in order to protect the surface. A good intermediate paint should be cohesive to the primer coat. It should be able to fill any irregularities in the primer coat, provide resistance to water and vapor and act as a barrier to any corrosive agents. In addition, it should be compatible with the chosen top coat.

Top coat

When getting a top coat for protective painting, factors such as aesthetics come into play. You need a top coat that acts as a protective coat and also gives the surface a pleasing appearance. Depending on the conditions of exposure, it must provide the first line defence to the surface. It should be adhesive to the intermediate coat that is being used. It also needs to offer excellent resistance to water vapor and corrosion from chemicals and other environmental agents. It also needs to offer protection against Ultra Violet (UV) rays from the sun. Glossier top coats are long-lasting and resistant to scratches. When choosing a top coat for the protective painting kit, you need to ensure it is aesthetically pleasing, and matches the style of the surface being painted.

The process of protective painting goes beyond ensuring structures looking beautiful; it also involves protecting against weather, sunlight, condensation and open exposure. For this reason, an effective protective painting system is essential. The various coats within the painting system need to be compatible with each other. This way, they will achieve the intended purpose of offering protection to the painted surfaces.

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