1, electrophoretic coating can realize complete mechanization and automation, which not only reduces labor intensity, but also greatly improves labor productivity, and is suitable for a large number of assembly line operations.
2. The electrophoretic coating has high permeability, can be completely dissolved or emulsified in water, and the viscosity of the prepared bath solution is very low, which can easily penetrate into the bag-like structure and gaps of the coated object, and is especially suitable for surface coating of special-shaped conductive materials.
3. The electrophoresis tank has high conductivity, coating ions can swim quickly under the action of electric field, and the surface of the coated object is neutralized to form an electrically neutral wet paint film. With the increase of thickening resistance of wet paint film, the deposition amount of coating particles gradually decreases, thus forming a uniform and detailed paint film.
4. The coating utilization rate is high, up to more than 95% or even 100%. Due to the low solid content and viscosity of tank liquid, less paint is brought out by coating, especially the application of ultrafiltration technology, the closed cycle of coating process is realized and the paint recovery rate is high.
5. The coating has strong corrosion resistance. Electrophoretic coating can form a uniform film under the action of electric field, so electrophoretic coating can significantly improve the corrosion resistance of the inner cavity, weld and edge of the workpiece.
6. The electrophoretic coating has low solvent content, which is beneficial to environmental protection and good production safety.
After 30 years' development, international coating suppliers, represented by the United States, constantly adopt new technologies and develop new products, so that electrophoretic coatings are constantly updated. A new generation of cathodic electrophoretic coatings should have the following characteristics:
A the swimming permeability of a new generation of cathodic electrophoretic coatings should be further improved. The higher the swimming permeability, the more uniform the film thickness inside the car body, thus improving the overall corrosion resistance of the car body, reducing the construction voltage and reducing the amount of paint.
B. improve the corrosion resistance of the edge. In the process of electrophoresis, due to the electrochemical effect of the coating, some edge parts are particularly thin, so corrosion is easy to occur here. The anticorrosion ability can be improved by improving the performance of the coating.
C. reduce the Yan-base ratio. Yan-base ratio is the ratio of pigment to resin in coatings. Reducing it can increase the content of resin, improve the fluidity of coating, reduce the settling speed of colloid, reduce pigment flocculation and pump protection, and reduce material consumption.
D. reduce the amount of solvent. The higher the solvent content, the greater the environmental pollution, which is not conducive to work. Reducing it is beneficial to protect the environment and save investment.
E. lead-free Wuxi is more environmentally friendly. Lead plays an important role in anticorrosion catalysis, passivation and accelerated crosslinking of electrophoretic coatings, but lead-containing pigments have a great influence on the anticorrosion of bare steel plates, and lead itself is a highly toxic element, which is strictly limited by environmental protection. The performance of tin is close to that of lead, and they are usually mixed.
limit
1, electrophoresis can only be carried out when electricity is on, so it is suitable for conductive coated objects (usually metals).
2. Electrophoretic coating process is not suitable for coated objects composed of various metals with different conductive characteristics. If some electrophoretic coatings are allergic to metal ions such as copper and tin.
3, electrophoretic coating wet film must be baked to form a dense paint film, so the coating object that can't withstand high temperature can't use electrophoretic coating process.
4. The renewal period of electrophoresis tank bottom is less than 6 months, so electrophoresis coating is not suitable for small batch production.
5. The properties of electrophoretic coatings on different substrates are different.
6. Strong technical force is needed as support, especially color electrophoresis. If you are not a professional, it is difficult to achieve the expected color effect.