Where the
world gathers for metal finishing
Q&As since 1989


-----

Electro-deposition painting

2003

Hello,
I'm researching about EDP for new project. Could you tell me briefly about EDP (Electro-deposition paint) and its process?

Thank you

Naruemol Chaiparsitthikul
-Nakhon-Ratchasima, Thailand

---

Hi, Naruemol

Electro-deposition painting is also sometimes called e-coating, electrophoretic lacquering, cationic electropainting and a few other terms. The component is electrified and submerged into a tank, and the oxidation or reduction process (very similar to electroplating) changes the soluble organic paint molecules to a thin "dry" non-conductive paint on the component.

Some of the advantages are that no solvents are required; 100 percent coverage is routine because once the paint has deposited in one spot it is insulative and the current flows to other areas; and the coatings are very thin compared to competitive technologies like powder coating. Disadvantage are that the paint must be kept quite pure and the required filter membranes can be a headache, and changeover of colors may not be real easy. The changeover issue may sometimes be addressed by post-dyes instead of coloring the electrodeposited paint. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 12, 2011