POLYESTER RESIN COMPOSITION AND FILM, OR POLYESTER COMPOSITE FILM AND METAL LAMINATE USING THE SAME, AND METHOD FOR REDUCING LOW-MOLECULAR COMPOUND IN POLYESTER

摘要

PURPOSE: A polyester resin composition and film is excellent in heat resistance, spreading, adhesion, shock resistance, flavor and extrusion workability and used for coating the inner and outer surfaces of a metal can. CONSTITUTION: The polyester resin composition comprises 30 to 90 wt.% of polyester A having a melting point of above 220°C based on ethylene terephthalate containing 0.1 to 2.0 mole % of a compound having 3 or 4 ester bonding functional groups; 70 to 10 wt.% of copolymer polyester B having a melting point of 150 to 210°C and a glass transition temperature of less than 20°C based on butylene terephthalate; and a hindered-phenol-based organic compound and/or tocopherol. The free terephthalate content is less than 20 ppm, the bishydroxyethyl terephthalate content is less than 60 ppm and the bishydroxyethyl terephthalate dimer content is less than 300 ppm.