500 mm min hardness 12 mm at obtained by a spring thickness type a testertear strength 2 mm at obtained by tensile thickness speed 500 mm min ______________________________________ in examples i and ii the thermoplastic resin was used as the base high molecular compound and in example iii the thermoplastic rubber was used as the base highmolecular compound and the above two materials were injection molded the compounding amount of the water soluble electrolyte and the water soluble high molecular compound respectively is most preferably from 1 to 5 weight parts fig2 shows a relative humidity surface resistance curve in which the compounding amount of the water soluble electrolyte and the water soluble high molecular compound respectively is varied in the scope of from 0 5 to 6 weight parts when the above compounding amount becomes less than 1 weight part the surface resistance becomes higher thereby the composition thus obtained is not available for practical use when the above compounding amount is over 5 weight parts the surface resistance becomes lower but both the inorganic salt and the water soluble high molecular absorb a water content in the atmosphere thereby the surface of the composition thus formed becomes whitely turbid accordingly its plastic deformation occurs and the quality as well as the outer appearance is deteriorated the same kind of test for the other examples was carried out and the nearly similar results were obtained in example iv the so called rubber was used as the base high molecular compound and molded by the compression molding fig3 shows a graph showing a relationship of the amount of additives with the surface resistance according to example iv in which the compounding amount of the water soluble.