Comments on "an essay on contact angle measurements" by Strobel and Lyons

The potential of contact angle measurements (CAM) as an analytical tool to characterize surface treatments or modifications is often not fully exploited. Agreeing with Strobel and Lyons, comparing contact angles is often much more reasonable than comparing deduced data like surface energies, because the latter are based on models, in turn involving the influence and knowledge of intermolecular forces at the respective interfaces. For a comprehensive picture, the measurement of contact angles itself has to be considered together with the appropriate model and the available techniques to carry out CAM. An appropriate measurement procedure will be given and a brief discussion of some models to derive free surface energy from CAM. The information that could be derived from contact angle measurements is very useful to characterize the outermost layer of a surface until it is carried out carefully. To compare the results with other working groups it is essential to describe t he measurement procedure properly.