Liquid bridge at the microscale significantly influences adhesion and separation behavior between particles and surfaces, particularly in miniature devices operating under humid environments. In this study, we employed total reflection imaging to observe, with high spatial resolution from below, the dynamic changes in the wetted area during the formation and rupture of liquid bridges. Simultaneously, we recorded the bridge shape from the side and measured the time-dependent variation in adhesion force. Experiments were conducted using distilled water and hexadecane, with each liquid placed between a spherical glass surface and a plate, which were brought into contact and then separated. The results indicated that the adhesion force is influenced by both the wetted area and the curvature of the liquid bridge. In particular, it was confirmed that the direction of curvature is associated with variations in the magnitude of the attractive force. This approach provides a useful framework for understanding the mechanical behavior of liquid bridges and their influence on interface dynamics in microscale applications.
Igarashi et al. (Wed,) studied this question.