Motion of colloidal particles near a plateau border in a freely suspended liquid thin film

The motion of a mcron-sized polstylene latex particle near the plateau bord er of a free-standing liquid thin film is experimentally studied. As the pa rticle approaches the plateau border, it is accelerated toward the border, Using an optical microscope and interference phenomena, we measure the defo rmed surface area and the position of the particle. From a simple geometric al model, we can calculate the capillary force on the colloidal particle in the film and the energy difference between the deformed film and the undef ormed film. Also, we find that tile friction coefficient of the particle in the liquid thin film is different from friction coefficient in the bulk.