Maintenance of texture preparation paint film

In addition to the embellishment effect, the pigment can significantly improve the function and function of the paint film, such as improving the adhesion of the paint film to the applied surface, improving the mechanical strength, anti-corrosion ability, temperature resistance, water resistance, oil resistance and anti-aging function of the paint film. These are the maintenance of the paint film. For metals, especially for steel, the most important is the anti-corrosion function of the paint film. The anti-corrosion function of the paint film is accomplished by a polymer resin and a pigment. This section analyzes the mechanism of anti-corrosion of paint film, as well as the demand for polymer resin and pigment. It also analyzes the anti-corrosion method of paint film commonly used in industry.

For corrosion protection, sandblasting or preparation of chemical conversion layers (such as phosphating) is required before steel painting; then primer is applied, and the primer film is supplied with a basic corrosion control; a medium coating is applied between the primer layer and the topcoat layer. The medium texture preparation coating and the topcoat layer reduce the oxygen and moisture permeability, and improve the anti-corrosion effect; the topcoat imparts the gloss of the paint film, the field fire resistance and the wear resistance.

texture preparation paint film anti-corrosion concept

In 1950, it was generally thought that the coating relied on the shielding effect to maintain steel and prevent water and oxygen from reaching the steel surface. However, later research found that the permeability of the paint film is high enough, the rate of water and oxygen passing through the paint film is higher than the rate of water and oxygen consumed by bare steel corrosion, that is, the shielding effect of the paint film cannot explain the effective maintenance of the paint film. Sex. Through the discussion, the concept of wet adhesion is heard. When water passes through the paint film, it can replace some of the orientations occupied by the paint on the steel surface. This is the wet adhesion of the paint film to the steel surface. If the wet adhesion is small, the paint film is foamed and dropped from the steel surface. If the wet adhesion is large enough, the steel can be kept from corrosion due to no displacement on the steel surface. Therefore, it is important to prevent corrosion of the paint film from reaching a high level of wet adhesion. In addition, low water permeability and oxygen permeability also contribute to corrosion resistance because they can delay the loss of wet adhesion.

The complete paint film maintains the metal by improving the wet adhesion of the paint film and by reducing the water permeability of the paint film and the oxygen permeability of the texture preparation. However, in some cases, because of other depiction requirements, the paint film can not completely cover the appearance of steel, and some paint film will break due to mechanical damage or other factors during the service period. In these cases, the selected skills are three types: ruthenium delamination, primer with passivating pigment, and zinc-rich primer. Therefore, the anti-corrosion of the paint film is divided into two aspects: the anti-corrosion of the paint film and the anti-corrosion of the paint film.