The influence of packing material wettability on the dispersion transient flow in a disc and doughnut pulsed column has been studied. The outlet Bow rate of the dispersed organic phase has been measured vs time until steady-state is reached (outlet Bow rate equals inlet dow rate). Experiments have been carried out with two types of packing materials, namely stainless steel (non-wetting) and PTFE (wetting). Comparisions and integral analysis of the results exhibit the effect of toluene wettability on the dispersion residence time with a PTFE packing. Considering the fact that no redispersion of the wetting film occurs, it is possible to derive the volume of toluene wetting the PTFE packing during the column filling. Two major effects are observed : on the one hand, the wetting process generates an apparent delay in the outlet Bow rate curve obtained with PTFE plates compared to that obtained with stainless-steel plates (transient regime). On the other hand, the slope of the outlet how rate is decreasing as the output dow rate value tends toward the inlet how rate (steady state). The first effect is due to drop-plate coalescence, whereas the second effect has been identified as drop-wetting film coalescence. From the experimental outlet Bow rate curves and observations, a wetting process model has been postulated to predict the wetting phase flow rate as the column is filled with the dispersed phase. The main parameters of the model are the wetting coefficient k(w), and the volumetric Fraction of the wetting phase Phi(w). The fitting of these parameters with experimental results reveals that the wetting rate of the drop-plate coalescence (transient regime) is two orders of magnitude larger than the drop-him coalescence rate (steady state).