A: Surface preparation, such as phosphating, for E-coating is more thorough than for either liquid or powder painting. Prior to applying the E-coat the metal surface MUST be pristine clean so that the E-coat dipping bath is not contaminated by the metal that will be coated.
E-coating is a dipping process, whereas liquid and powder coatings are usually spray applied using equipment that is specific to each coating technology.
The following web site
http://www.electrocoat.org/faq.html provides you will several Q&As that you can read. Also, the Electrocoat Association has compiled a book on the topic.