The polyvinyl chloride resin has a polymerization degree of 300 to 2,000, preferably 600 to 1,500, and includes a polyvinyl chloride resin alone and a resin obtained by the copolymerization of vinyl chloride and other monomer such as an olefin monomer, a dierio monomer, a halogenated vinyl monomer, an acrylic ester monomer, a methacrylic ester monomer, a vinyl ester monomer or a styrene monomer.