Application and precautions of electrophoretic coating processing

Electrophoretic coating is a widely used process in metal surface coating. It has relatively high requirements for process operation and equipment, but its application effect is also excellent. In the processing, occasional defects in the appearance of workpieces may occur. Today, let s briefly discuss the reasons for these problems.

Normally, the surface of the workpiece after processing should be smooth and free from particles, spots, or any abnormalities. If these defects are present, it not only indicates the presence of such flaws but also means that the coating may have uneven gloss or smoothness, making the paint surface itself appear rough with an uneven texture.

This is actually due to the poor leveling effect and poor thermal compression performance of the re-dissolved or electrophoretic coating film. Additionally, it s because the bath liquid contains pigments in relatively high amounts and low solvent content. Another reason is that the flow rate of the bath liquid around the coating is relatively low, or it s due to the presence of fine particles and poor filterability. In other words, during the electrophoretic coating process, the coating film is re-dissolved, resulting in thinning of the coating film, leading to light loss and edge opening phenomenon.