3 Functions of Surface Coatings

15th January 2024

Coatings can be applied to the surface of objects using various application techniques, forming an adherent and solid film. It can provide protection, decoration, and functional enhancement to the substrate, including metal, wood, concrete, plastic, leather, paper, glass, and other materials.

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The primary function of coatings is to protect the substrates. Objects exposed to the atmospheric environment are subjected to various corrosive factors. Metals undergo electrochemical corrosion caused by oxygen, water, electrolytes, acid rain, salt spray, etc. Plastics, wood, and paper degrade due to ultraviolet radiation. Concrete weathers and deteriorates due to carbon dioxide and acid rain in the air. Microorganisms and their metabolic by-products have a significant destructive effect on all substrates, tarnishing their appearance. Inner walls of containers exposed to various corrosive media (such as oil tanks, solvent storage tanks, facilities for storing and transporting water, acids, alkalis, salts, etc., as well as pipes for oil, gas, water, etc.), sewage treatment tanks, harbor facilities, etc., are constantly subjected to corrosion.

The basic function for coating is to provide a barrier against corrision so as to enhance the durability and longevity of the substrates. Coatings can isolate and shield the corrosive agents like oxygen, water, electrolytes, acid rain, salt spray, or protecting the substrate by slowing down corrosion through the addition of special additives. Furniture and plastic products often come into contact with corrosive materials such as detergents, alcohol, vinegar, etc. Coatings can help provide appropriate protection. Products and equipment subjected to mechanical impacts, scratches, scouring from heavy rainstorms, and abrasion from wind and sand, can be protected through coatings.


Metal Corrosion without Coatings


Coatings can significantly improve the appearance of the substrate, providing vibrant colors, varying degrees of gloss, rich textures, surface patterns, and other artistic and decorative effects. This meets the increasingly diverse and personalized demands of users. High decorative coatings, commonly used in automobiles, plastics, furniture, instruments, leather, and high-grade paper, often constitute a crucial part of the added value of products. The combination of coating performance and application processes forms the foundation for achieving the intended decorative effects.

Garage Floor Coatings

Garage Floor Coatings

Functional Role

Protection and decoration, while constituting a category of functions, refer here specifically to the functionalities of specialty coatings materials, predominantly showcased in applications related to national defense and military industries. Examples include electromagnetic shielding, radar wave absorption, sonar wave absorption, invisibility and camouflage coatings, solar heat reflection or absorption coatings, ship anti-fouling coatings, fire-resistant coatings, high-temperature-resistant coatings (200~2000°C), thermal insulation, ablative coatings, damping and noise reduction coatings, deck non-slip and anti-icing coatings, and self-cleaning, heat-reflective ship hull coatings.

There is an increasing demand in the market for specialty functional coatings, such as waterproof, thermal insulation, and heat-reflective coatings for roofs in architectural paints, as well as waterproof, insect-resistant, and mold-resistant coatings for interior walls.