Selection of leveling agent

The leveling of water-based coatings is a problem. Solvent based systems can promote leveling through surface tension differences and low viscosity. By selecting the appropriate solvent, the evaporation of the solvent can cause changes in surface tension. Therefore, the difference in solvent evaporation between peaks and valleys can lead to differences in surface tension, promoting system leveling.

Unfortunately, we found that the evaporation of water in water-based coatings resulted in minimal changes in the surface tension of the system, which remained relatively uniform at a low level. This caused water-based coatings to lose an important leveling force. Therefore, the leveling of water-based coatings will depend more on viscosity.

During the drying process of water-based coatings, after the high shear force disappears, the viscosity increases sharply with the evaporation of water, especially for spraying systems. The leveling time in low viscosity states is relatively short, which is not conducive to leveling.

Given the above reasons, it is completely necessary to make such complex and meticulous designs in the selection of rheological agents, the combination of film-forming agents, pH regulators, and the selection of pH values.

The leveling of water-based systems does not rely solely on low viscosity leveling. There are also plenty of leveling agents available on the market for everyone to choose from, including hydrocarbons, fluorocarbons, silicones, esters, and acrylics.