25 июля, 2015 
Malyar There are a number of excellent books on paint formulation and this chapter is not the place to go into detail on such a complex subject.. The basic principles of formulating electrodeposition paints are the same as used in formulating any other paint, but the parameters such as pigment volume concentration tend to be somewhat different from those of dipping and spraying paints.
Pigment/binder ratios are normally in the range 0.5:1 to 0.3:1, the lower values being the more usual. This results in a much lower pigment volume concentration, and these tend to be in the region of 10%. In fact a pvc of 10% and a P/В ratio of 0.3/1 make a good starting point for formulating a paint.
Also to be taken into consideration is the degree of neutralisation of the resin. This should be the minimum consistent with stability of the bath. This will be a little higher than the minimum necessary to prevent the resin precipitating when first made up, because in most cases some of the neutralising agent will be lost from the tank when in use. This can be made up, of course, and if the counter electrode is not in its own compartment, then there will be a build up of the neutralising agent in the tank.
The pigments must be chosen not only for their opacity, colour, etc. but must be free of contamination by electrolytes. Pigment manufacturers normally sell special electrodeposition grade pigments where this is likely to be a problem.
Electrolyte contamination is a serious problem in an electrodeposition tank and quantities of the order of 50 ppm will give rise to fill defects, as well as reducing the rupture voltage and the coulombic efficiency. This is a matter which is relevant to running the tanks rather than formulating either resins or paints.
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