Mechanism on Splitting of Liquid Film Sprayed from Mist Aerosol Containing Oil-in-water Emulsions as Mist Aerosol Formulation

We examine the effect of surfactants on spray characteristics of mist aerosol containing oil-in-water (O/W) emulsions to evaluate the mechanism on the splitting of liquid film sprayed from mist aerosol containing O/W emulsions as mist aerosol formulation. We proposed that the splitting of liquid film sprayed from mist aerosol containing O/W emulsions as mist aerosol formulation was attributed to the adsorption of oil droplets to air/water interface in liquid film sprayed from mist aerosol. The splitting of liquid film sprayed from mist aerosol containing O/W emulsions differed with type of surfactants. This indicates that the adsorption of oil droplets to air/water interface in liquid film sprayed from mist aerosol is controlled by surfactants. We also found that the prompt adsorption of surfactant molecules themselves to air/water interface enhanced the splitting of liquid film sprayed from mist aerosol. Namely, the prompt adsorption of oil droplets and surfactants to air/water interface in liquid film leads to the earlier splitting of liquid film, and the resulting larger angle and area of mist sprayed from mist aerosol containing O/W emulsions.