defoamer

chemistry

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June 25, 2026

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In chemistry, a defoamer is a substance that destabilizes or breaks down foams. Foams are colloidal systems where gas bubbles are dispersed in a liquid. While some substances, like soaps, detergents, and proteins, act as foam stabilizers, defoamers counteract this effect.1

Defoamers are often used in liquid coatings to prevent problems during manufacturing, packaging, and application, such as film defects caused by bubbles. The exact mechanism of defoamers is not fully understood, but they are thought to work by destabilizing the surface films of bubbles or by spreading on these films and breaking them. Some defoamers are based on silicone oils with added silica particles. Certain types of surfactants can also function as defoamers.23

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surface coating
Defoamers
One problem with specialty additives is that they often have a surfactant nature and consequently stabilize foam in the liquid coating. Portions of the coating polymer also have a surfactant nature, and they, too, contribute to foam stability. Foam often causes problems during manufacture…
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One problem with specialty additives is that they often have a surfactant nature and consequently stabilize foam in the liquid coating. Portions of the coating polymer also have a surfactant nature, and they, too, contribute to foam stability. Foam often causes problems during manufacture…
Read More