TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The crosslinking agent is divinylbenzene. The blowing agent is a mixture of two or more selected from butane, pentane1 and cyclohexane. The pentane is a mixture of n-pentane and isopentane in a weight ratio of 60:40 to 70:30. The styrene monomer is a styrene monomer alone or a mixture of a styrene monomer as a main component and acrylonitrile or alphamethyl styrene.    TECHNOLOGY FOCUS - POLYMERS - Preferred Process: The process further comprising coating the EPS resin with a coating agent of glycerol monostearate, glycerol tristearate, zinc stearate and/or hydrogenated castor oil (HCO), where the coating agent is used in an amount of 2000 to 10000 parts per million, based on 100 parts by weight of the EPS resin. The polyoxyethylene sorbitan monolaurate is added when a polymerization ratio reaches 70-90%. Preferred Composition: (II) further comprises polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate and/or a fatty acid ester of glycerine acetic acid. The molecular weight of the EPS resin is 250000-350000. EXAMPLE - Styrene monomers (250 kg), polystyrene recycle beads (6.6 kg) (molecular weight: 250000-350000), benzoyl peroxide (825 g), t-butyl perbenzoate (125 g) and dicumyl peroxide (750 g) as initiators, divinylbenzene (61 g) as a crosslinking agent, Sasol-wax (250 g) and hexabromocyclododecane (1.5 kg) were injected into a reactor (700 l) equipped with an agitator and stirred for 30 minutes to prepare a dispersion solution. Then, tricalcium phosphate (400 g) as a dispersing agent and ionized water (250 kg) were added and stirred for 30 minutes. The reaction solution was elevated to 90degreesC for one hour and maintained at the same temperature for 30 minutes. Then, a 10% aqueous solution of potassium persulfate (6.1 g) as a dispersion aid was added to the reaction solution. At 3 hours after the addition of the dispersion aid, tricalcium phosphate (400 g) as a dispersing agent was added and the reaction solution was maintained at 90degreesC for 4 hours and then elevated to 100degreesC for 50 minutes. In the course of the elevation of the reaction temperature, polyoxyethylene sorbitan monolaurate (200 g), a 10% aqueous solution of alkyldiphenylether disulfate (0.61 g) as a dispersion aid and dibutyltin dimaleate (6.1 g) as a thermal stabilizer were added. When the elevation of the reaction temperature to 100degreesC was completed, a mixture of butane (5 kg), cyclohexane (1.25 g) and pentane (13.75 kg) as a blowing agent was added. The reaction solution was maintained at 100degreesC for 40 minutes, elevated to a temperature of 125degreesC for 50 minutes and maintained at the same temperature for 1.5 hours and then cooled to room temperature for 2 hours to give the expanded polystyrene resin.