ABSTRACT
Foam is an especially severe problem in both water-based and water/solvent-based paints particularly where emulsion polymers are used as binders. The paint manufacturer will use small particle size emulsion polymers for most paints. Industrial paints are applied by for example spraying, flood-coating, electrocoating, dipping, curtain coating, and machine reverse roller coating. The main products of the industry are water-based emulsion paints for household use, solvent-based household paints, and mixed water/solvent-based paints for industrial use. Development of antifoams for aqueous emulsion paints has followed essentially empirical lines. In the case of aqueous media the active antifoam ingredient must also be hydrophobic. Blends consisting of hydrocarbons with fatty acids and various other ingredients formed the basis of the early antifoams used in the paint industry. Potential storage problems are always possible with multiphase antifoam systems. Use of a single-phase system avoids many of these problems.
