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Post Rinsing

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Post rinsing, using a closed loop rinse system, is the most effective method to remove the loosely adhering cream-coat, and to recover nearly 100% of the "carry out," retaining it in the system for maximum efficiency.

An ultrafilter, which extracts water, solvent and low molecular weight species of the paint as a clear solution called "permeate", is the basis of the closed loop rinse system.

The permeate is used to rinse the workpiece in a succession of individual spray and/or immersion rinse stations enclosed in a rinse tunnel following the dip tank. The final rinse in this system is virgin deionized water. Sufficient drain time is allowed between each rinse station, and following the final rinse, to recover nearly all of the rinse material and retain it in the system. Following the final deionized water rinse, and after sufficient drain time, most electrodeposition systems utilize an automatic air blow-off to remove water from the exterior surfaces before baking to avoid water-spotting.

DuPont expresses appreciation to Xcel Industries for use of photograph.