Benetzungsmuster

Benetzungsmuster refers to spatial patterns formed by the distribution of a liquid on a solid substrate caused by variations in wettability, surface energy and topography. On chemically or geometrically heterogeneous surfaces, the liquid does not spread uniformly; instead, it forms stripes, patches, or labyrinthine patterns determined by local contact angles, hysteresis and capillary forces. The phenomenon is studied in surface science and fluid mechanics, with theoretical models including the Young–Dupré equation for the intrinsic contact angle, along with effective models such as Wenzel and Cassie–Baxter for rough or heterogeneous surfaces. Dynamic effects such as contact-line pinning, evaporation and Marangoni flows can further sculpt the pattern during spreading or drying.

Benetzungsmuster are encountered in coatings, inkjet or screen printing, and microfluidics, where controlled wetting is used to guide liquid flow or confinement. Patterned substrates—such as hydrophilic/isotropic stripes or micropillared textures—enable selective spreading, confinement or self-alignment of droplets, enabling applications in biosensors, lab-on-a-chip devices and optical surfaces.

Measuring and characterizing benetzungsmuster involves contact-angle measurements, high-speed or confocal microscopy, and imaging of droplet footprints, sometimes combined with surface-energy mapping. In practice, the design of benetzungsmuster requires consideration of the surface chemistry, texture scale relative to the liquid’s capillary length, and the desired functional outcome.

See also: wetting, contact angle, Cassie–Baxter, Wenzel, capillarity, surface patterning, microfluidics.