CONTACT LINE DISTORTION BY NONWETTING DEFECTS ON A COMPLETELY WETTED VERTICAL WALL - AN EXPERIMENTAL-STUDY

We present a study of contact line configurations on a completely wetted vertical plate near non-wetting vertical-line defects of varying width. The contact line shape is compared with a recently obtained solution for distortions caused by a localized force. Fits to the theory are excellent after the introduction of a new characteristic length scale depending on the defect width w. Two regimes are observed as w is varied: for narrow defects, the behaviour of the characteristic healing length correlates well with the defect width, while for wide defects, the healing length saturates to a constant value.