POLYESTER RESIN COMPOSITION

PURPOSE:To provide a polyester resin composition extremely excellent in heat sealability, flavoring property, film formability (extrusion processability) and mechanical strength. CONSTITUTION:The polyester resin composition comprises 100 pts.wt. of a branched polyester resin mixture and 5-50 pts.wt. of an ethylenic polymer, the branched polyester resin mixture consisting of (A) a polyester resin comprising an aromatic dicarboxylic acid component containing terephthalic acid as a main dicarboxylic acid and a glycol component containing ethylene glycol as a main glycol, containing a tri- or higher-functional polycarboxylic acid or polyol in an amount of 0.1-1.5mol/% based on the whole acid components or the whole glycol components, and having a reducing viscosity (etasp/c) of >=0.7 and a polystyrene-converted average mol.wt. (Mz) of 250X10 to 600X10 and (B) a non-branched polyester resin having a reducing viscosity (etasp/c) of >=0.7 in an (A)/(B) weight ratio of 95/5 to 40/60.