In ceramics, leveling agents, defoamers, and surfactants represent three key categories of additives that ensure suspension stability, proper application performance, and the desired aesthetic quality of the finished product.
Used individually or in combination, they generally improve wettability and spreading of suspensions while at the same time preventing the occurrence of surface defects.
Below is an overview of these three families.

Surfactants

They reduce the surface tension of liquids, improving wettability and promoting a more uniform distribution. Thanks to their molecular structure—comprising a hydrophilic and a hydrophobic part—they enhance dispersion efficiency.

Defoamers

They counteract foam formation by destabilizing bubbles and preventing their development. This function is crucial for avoiding defects caused by entrapped air in ceramic suspensions.

Levelling agents

They optimize surface appearance by eliminating irregularities and unevenness during drying. In many cases, they also provide a secondary defoaming action, ensuring a smooth and consistent glaze application.