During the production and application of paint systems, foam is an undesired side-effect. This part gives you the theory of defoaming technology.

Foam created by surfactants, polymers, or solids that impart a stretchy skin to the liquid, inhibit drainage and capture small bubbles. Defoamers create weak spots in the bubble wall, and/or able to promote gravitational flow of water from the bubble wall, or release micro-bubbles.