The Direct Fluorescence method was used to study the healing process during latex film formation above the glass transition temperature. The latex film was prepared from pyrene (P)-labeled poly(methyl methacrylate) (PMMA) particles. Heptane was used as a mixing agent. The steady-state fluorescence technique was employed to measure the density of polymer chains crossing the particle-particle interface. Various latex films with different latex content were used to study the transparency below and above the healing temperature. Crossing density was found to depend linearly on (time)(1/2), which was proposed by Prager and Tirrell. (C) 1996 John Wiley & Sons, Inc.