Additives Common to both Emulsions and Water Reducible Systems

Additives Common to both Emulsions and Water Reducible Systems (i) DispersingAVetting Agents 

It is difficult, if not impossible, to accurately define the difference between a dispersant and a wetting aid. One simple, but general, definition is that dispersants keep the dispersed particles apart, whereas wetting aids reduce surface tension which may permit dispersion. A wetting aid can be a dispersant, but a dispersant cannot be a wetting aid. 

Dispersing aids are almost invariably a necessity in aqueous systems, since the polymers have an inherently poor ability to wet and disperse pigments. 

They fall into two distinct types, namely  

The first category is used to enhance the performance of the second category. However, there are additives which can be used without a resin. For example, some pigment dispersions use propylene glycol as the binder with additives to help disperse the pigments. 

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