As described in a provisional CSP p

As described in a provisional CSP patent [49], several solvents such as organic alcohols, ketones, esters, water and/or mixtures can be used to densify materials at low temperature. The pH of an aqueous solvent may be modified by the introduction of additives to promote the dissolution of the target compound. Several polar (ε’ > 50) and semi-polar solvents (20 > ε’ > 50) (Fig. 2) have been employed in cold sintering as a high relative permittivity of the liquid phase promotes the dissolution of inorganic compounds. The boiling point ofthe solvent should also be considered, as this property must be within the attainable temperature window of the cold sintering apparatus.