A method for manufacturing a three-dimensional object includes steps of: a) providing a digital description of the object as a set of voxels; b) sequentially creating an actual set of voxels corresponding to the digital set of voxels; wherein at least one voxel comprises a water-soluble poly urea derived from: i) a polymer or mixture of polymers and a composition ii) selected from the group consisting of: urea, diisocyanate (methylene diphenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate) and mixtures thereof.