Various materials and their products in the process of processing, transportation, storage, its surface is easy to produce or
stick foreign matter, such as machining burr, oxide skin, oil, etc., these surface contaminants will affect the compactness of the coating and the bonding strength with the matrix. Coating pretreatment of the mainThe objective is to remove these substances and perform the appropriate surface chemical conversion to provide suitableCoating requirements of the substrate, in order to increase the adhesion of the film, prolong the service life of the film, Give full play to the protective effect and decorative effect of coating.
Therefore, spray the content before processing. It mainly includes the following aspects:
phosphating film was able to provide a very appropriate base for paint coating, is due to the following effect ：
1) Provides a clean, uniform, grease-free surface on the basis of complete degreasing
2) enhances the adhesion of organic film to the substrate due to physical and chemical action It is not difficult to understand that the porous structure of phosphating film increases the surface area of the substrate, so that the connection area between the two increases correspondingly, and the beneficial mutual permeability between the two film layers is generated. At the same time, the chemical interaction between unsaturated resin and phosphate crystal also enhances its binding force
3) provide a stable non-conductive isolation layer, once the coating damage, it has the role of corrosion inhibition, especially for anode incision The first point is often neglected Only to completely to the best of the oil to form a satisfactory phosphating film So the phosphating film itself is the most intuitive effect of pretreatment technology of the most reliable a self-check.