Electrophoretic coating lines for decorative application

Electrophoretic coating lines for decorative application: what they are and how they work

The development of electrodeposition technologies plays an increasingly important role in various different industries. These technologies involve the presence of both “anaphoresis”, during which the item constitutes the negative pole, and “cataphoresis”, where the item is the positive pole. Electrophoretic coating lines for decorative application are one of the most important machines used in the industry.

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Electrophoretic coating lines for decorative application work in a similar way to immersion tanks. In practice, the pieces are completely immersed in a tank filled with paint that has been diluted with water. Obviously there is a continuous flow of electric current inside the tank.

At a later stage, the coating deposits on the item, which is one of the two electrodes; the solubilising agent in the binder, on the other hand, is discharged onto the other electrode and opportunely removed. Consequently, the agent that has deposited on the item will already be insoluble when removed from the tank.

Following electrodeposition, the item passes through a tunnel where it is mechanically sprayed to remove and recover any residues. As with immersion tanks, the item is placed in a furnace to promote the reticulation of the coating.

However, unlike immersion tanks, items to be coated with an electrodeposition process carried out by an electrophoretic coating line for decorative application, must be of the same shape and size, or only slightly different. This practice helps to avoid dangerous distortions in the electric field.

The coating method used by electrophoretic coating lines for decorative application guarantees an even coating, with a thin film and excellent corrosion resistance. Used as a base coating for products in the automotive industry and in the household appliance and agricultural machinery sectors, today this type of coating is used more and more often as a single final coat for pumps and lighting fixtures.