A dispersion of phase-change materials is proposed as an experimental biphasic refrigerant. The phase-change material is water stabilized by a tri-dimensional network of polymer, obtained by using a polymerizing process. The particle contains 90 per cent of water and has the consistency of a viscoelastic solid above the phase-change temperature. The measured values of the physical properties of the biphasic refrigerant, that is, specific heat, latent heat, density and viscosity, are presented and discussed for the considered temperature range. A supercooling phenomena is observed if the size of the particles becomes lower than 1 mm. The degree of supercooling however does not exceed 3 degreesC. The various advantages of this slurry are presented and the comparison with a common single-phase carrier fluid has proved how great its properties are as a secondary refrigerant. This material appears well adapted for a wide variety of schemes where the production involves low-temperature intervals, such as the refrigeration industry. Copyright (C) 2001 John Wiley & Sons, Ltd.