Dynamic Surface Tension and Spray Application: Why Wetting Agent Selection Determines Coating Quality
In spray application, atomized droplets strike the substrate and spread within tens of milliseconds. Whether the surfactant has time to adsorb onto the newly formed gas-liquid interface determines whether the droplet can effectively wet the substrate — this is the significance of dynamic surface tension.
Static vs Dynamic Surface Tension
Static surface tension is the equilibrium value; dynamic surface tension reflects the adsorption rate of the surfactant onto newly formed interfaces. For a highly dynamic process like spraying, if the surfactant diffuses too slowly, the surface tension is still high when the droplet reaches the substrate, causing cratering and bare spots.
Advantages of Acetylenic Diols
Acetylenic diol surfactants diffuse quickly and can reduce dynamic surface tension within milliseconds, making them particularly suitable for spray application systems.
Related Products
Toynol Superwet-320 (low-foam acetylenic diol wetting) and BWA-925 (substrate wetting) perform excellently in spray waterborne systems.