The role of the coating is determined by the performance of the coating. Of course, the performance and role of the coating need to be manifested by the coating that is firmly attached to the surface of the product after painting, in order to play the real role of the coating. The role of the coating is also greatly related to the thickness and density of the coating. Except for powder coatings and high-solids coatings that form thicker coatings after being coated together, for tower types and varieties of solvent-based coatings, the coating formed after one coating is generally not more than 25um thick, and such thin coatings cannot be used. Resist the intrusion of external corrosive media, the erosion of chemicals and the impact and collision of machinery for a long time, etc., and cannot protect the surface of the product, let alone have good decorative properties.
Therefore, almost all products coated with high solid content and powder coatings are coated with multi-layer coatings (also known as composite coatings). Using different types of coatings with different properties and uses, the respective coatings formed after coating play the role of their own coatings and together form a dense coating with a left and rear thickness, which truly plays the important purpose of coating protection and decorative products.
Choice of primer
1. The choice of primer is in direct contact with the surface of the product material. Generally, anti-rust pigments and inhibitory pigments are added to prevent rust and passivation on the metal surface. The performance of primer has strong adhesion to the surface of metal or other materials, and also has good adhesion with the upper coating.
Choice of intermediate coating
2. The choice of intermediate coating requires the coating of products with high decorative or strong protective properties or when the coating is required to have certain decorative and protective properties due to insufficient surface flatness of the material, the intermediate coating is used. This coating has the function of linking the previous and the next, and is generally called the second primer (or second pulp).
Paint selection for surface coatings
3. The selection of surface coatings requires excellent resistance to external corrosion, certain physical and mechanical properties or special properties and functions. Improper surface coating is the first barrier to protect the surface from external corrosion and mechanical impact, and it also requires a decorative coating appearance with bright colors and luster.
[Recommended coating thickness measuring instrument]
