Autodeposition is a unique, waterborne organic coating process
which uses chemical reactions to achieve deposition of a high
quality finish on an assortment of substrates. The autodeposition
process is simple in comparison to other processes used for
applying corrosion-resistant coatings.
Autodeposition tanks
Following conventional cleaning and rinsing stages, metal
parts are immersed in a coating chemical bath where the deposition
of pigment and resin particles takes place. The growth in thickness
of the film is time dependent. There is an initially rapid deposition
rate followed by a decrease in growth limited by the diffusion
of ions on the metal surface and then "self-sealing"
of the coating. A protective barrier film is formed wherever
the coating bath makes contact with the metal workpiece.
The autodeposition coating process reduces the complexity
required by competing technologies. It requires no electric
current, because self-limiting organic coatings are developed
through a chemical reaction with the metal surface. Because
the process coats anywhere it wets, it generates exceptionally
uniform protective coatings even on difficult to coat parts.
These parts are coated at a fraction of the conventional energy
costs of competing technologies.
No conversion coating is required; the only pretreatment necessary
is cleaning. With no Volatile Organic Compounds (VOCs), no toxic
heavy metals, and low-temperature curing, air emissions are
minimized and the work environment is improved.
