PURPOSE: To improve the dressing and grinding quality by dispersing the fine bubbles, coarse abrasive material, and fine abrasive material in the matrix of the synthetic resin.

CONSTITUTION: Powder of nylon 6 and the abrasive material of alumina are mixed together. This mixed powder 3 is packed in pattern holes 2 formed in a mold plate 1, and placed between electrodes to execute the high frequency heating to melt the powders of synthetic resin. The heating for a short time does not melt the powders 3 of synthetic resin perfectly, and the fine bubbles are dispersed within the media to be formed, and no skin layers are formed on the media surface. After the high frequency heating, the mixed stuff packed in the pattern holes 2 of the mold plate 1 is slightly pressed with a pressing pattern to arrange the media shape, and after cooling, the formed media is taken out of the pattern holes 2 of the mold plate 1.