Electrophoretic painting technology is widely used in industrial production due to its efficiency, uniformity, and environmental friendliness. However, the issue of surface roughness in electrophoretic coatings sometimes occurs, affecting the product’s appearance and protective performance. This article will delve into the causes of roughness on electrophoretic paint surfaces and explore solutions.

　　The causes of roughness on electrophoretic paint surfaces are diverse, mainly including the following aspects. Firstly, issues with the paint itself are a significant factor. Poor pigment dispersion can lead to granular protrusions on the coating surface. This can be caused by factors such as the nature of the pigment itself, the selection or incorrect amount of dispersant, and insufficient dispersion time. In addition, poor paint stability can also lead to problems. The paint may deteriorate during storage or use, causing pigment precipitation, resin precipitation, etc., which in turn affects the smoothness of the coating. Paint stability is affected by factors such as temperature, pH value, and solvent content. Impurity contamination should not be overlooked. Impurities in the paint, such as dust, oil污, and agglomerates, can adhere to the workpiece surface during the coating process, forming protrusions and resulting in a rough surface.

　　Secondly, improper pretreatment is also a key factor. Inadequate degreasing can lead to residual oil on the workpiece surface, which affects the adhesion and flowability of the electrophoretic paint, resulting in defects such as shrinkage holes and orange peel on the coating surface. Uneven or defective phosphating film can also affect the smoothness of the coating.

　　Thirdly, improper control of electrophoretic process parameters can also lead to surface roughness. Improper selection and control of parameters such as voltage, electrophoretic time, solid content, and paint temperature can result in uneven coating thickness and poor surface leveling.

　　Finally, equipment maintenance and baking processes also require attention. Regular cleaning of electrodes, the proper operation of the tank liquid circulation filtration system and ultrafiltration system, as well as appropriate baking temperature and time, all affect the final quality of the coating.

　　To address the above-mentioned causes, the following measures can be taken to solve the problem of roughness on electrophoretic paint surfaces. Firstly, optimize the paint formulation and preparation process to ensure uniform pigment dispersion. Control the storage and use conditions of the paint to maintain its stability. Strengthen paint filtration to remove impurities. Secondly, strengthen the quality control of pretreatment to ensure that the workpiece surface is clean and free of oil污, and that the phosphating film is uniform and dense. Thirdly, strictly control electrophoretic process parameters. In addition, regularly maintain equipment, clean electrodes regularly to ensure uniformity of the electric field, and regularly check and maintain the tank liquid circulation filtration system and ultrafiltration system. Finally, optimize the baking process to ensure proper curing of the coating.

　　In conclusion, roughness on electrophoretic paintsurfaces is a complex and comprehensive problem that requires analysis and solutions from multiple aspects. By optimizing the paint, strengthening pretreatment, controlling process parameters, maintaining equipment, and optimizing the baking process, the problem of roughness on electrophoretic paint surfaces can be effectively improved, enhancing the product’s appearance quality and protective performance.