Additives:

1. dispersants – to separate and stabilize pigment particles (acrylic polymers )
2. driers – to accelerate drying time.
3. anti-settling agents – to prevent pigment settling.
4. bactericides – to preserve water based paints in the can
5. defoamers :  defoamer or an anti-foaming agent is a chemical additive that
   reduces and hinders the formation of foam in industrial processliquids. The terms
   anti-foam agent and defoamer are often used interchangeably. Commonly used
   agents are insoluble oils, polydimethylsiloxanes and other silicones, certain alcohols,
   stearates and glycols. The additive is used to prevent formation of foam or is added
   to break a foam already formed.