An improved image resolution in thermo-transfer duplicating processes is accomplished by means of dispersing a plurality of thermally conductive particles in the dye-wax layer of transfer material used in such processes and applying an electrical or magnetic field to the transfer material layer sufficient to orient and align the particles parallel to the direction of the field. In this way the improved dye-wax layer of transfer material is capable of greater thermal conductivity in the direction transverse to the layer than in the lateral direction of the layer.