Contact Angle Testing
Contact angle is a measurement used to determine a surfaces hydrophilic or hydrophobic properties. The ability of a liquid to spread over a surface with out forming droplets determines its hydrophilic characteristics. In contrast to this, a surface that does not allow the water to spread and instead creates water droplets or beading is considered to be hydrophobic.
The contact angles are precise measurements of the surface energy of the material itself vs. the cohesive forces associated with water or other liquids being tested.