Electrophoretic paint (E Coat) is now the finish of choice within the automotive industry where high corrosion resistance is required on sub frame components. This is generally far more durable and offers a low cost alternative to powder coating and is becoming ever more popular is general industrial or retail applications where a high corrosion resistance and aesthetically pleasing finish is required.
E-coat Epoxy Type (electrophoretic painting) offers a high corrosion resistance, normally in excess of 1000 hours salt spray resistance as well as an excellent aesthetic appearance. When applied to such coatings such as phosphate, zinc or zinc-nickel the corrosion properties can be increased even further. In addition, unlike sprayed or dipped coatings the E-coat finish gives a uniform density of coating over the whole part regardless of the complexity of the product. This surface finish provides a hard surface coupled with good chemical resistance giving excellent wear properties and is an excellent alternative to powder coating on many applications.
E-coating is a method of painting which uses electrical current to deposit the paint. The process works on the principal of "Opposites Attract". This process is also known as electrodeposition or KTL (Kathodische Tauchlackierung) cathodic dip painting
The e-coat process can be separated into four basic zones:
Pre-treatment
Electrocoat Bath and Ancillary Equipment
Post Rinses
Bake Cure Dry Oven
Typical Ecoat Process Sequence
1. Spray degreasing
2. Immersion degreasing
3. Water rinse.
4. Surface activation
5. Zinc phosphate coating (chromium free).
6. Demineralised water rinse dip
7. Demineralised water rinse dip
8. Demineralised water rinse spray
9. E-coating coating thickness from 10 up to 40 µm
10. UF cascade spray rinse.
11. UF rinse.
12. Demineralised water rinse spray
13. Drying of the parts – compressed air blow.
14. Three stage electric or gas baking of coating with thermal, infrared stove drying oven