Cataphoretic and anaphoretic emulsions

Manufacturers of cataphoretic and anaphoretic resists have previously reported the benefits of their own particular processes, and in doing so some of the advantages of their product and disadvantages of competitors products seem to have been rather exaggerated [4]. Many of these advantages and disadvantages are not relevant [5]. 

However, the major potential problems associated with each type of resist do depend on whether it is coating the reducing (cathode) or oxidizing (anode) electrode. 

In cataphoretic deposition no metal ions are incorporated into the coating from electrode dissolution, but the volume of hydrogen produced can cause problems through the formation of resist defects (pinholes) if it is not removed. 

In anaphoretic deposition much less gas is evolved from the anode, but metal ions dissolved from the anode are incorporated into the film, very few of them passing through into the resist bath. It has been recognized in the electrodeposition of paints [3] that anaphoretic coatings are more susceptible to corrosion than cataphoretic coatings, and they result in poorer performance. 

In fact, both of these potential problems have solutions described in section 2.4.9. 

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