A material for use in fabricating three-dimensional objects includes a mixture of thermoplastic particles and a water-soluble polymer matrix formed as a film that is fusible into a non-water soluble state when exposed to heating. The film further includes a surfactant system bound to the thermoplastic particles, the surfactant system providing an inversion property such that the thermoplastic particles are hydrophilic but, upon a fusing of the film, become hydrophobic as the surfactant become incorporated into the bulk.