TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The polyester film further comprises titanium atoms (1-30 ppm). The polyester film has: at least one white layer (formed by coating) with a thickness of 1-10 mu m; at least one adhesion layer on the white layer, which exhibits adhesion to an adherend containing an ethylene-vinyl acetate copolymer; at least one inorganic layer having a moisture permeability of 10-6 to 1 g/m2.d; and at least one layer comprising a fluororesin layer having a thickness of 1-10 mu m or a silicon resin layer having a thickness of 1-10 mu m. Preferred Components: The hydroxy groups on the surface of the film are present at 0.05-0.3 equivalents/t. The intrinsic viscosity of the film is 0.6-0.9 and the thickness of the film is 200-400 mu m. The inorganic layer is a vapor deposition film formed by vacuum deposition. Preferred Method: The method further comprises synthesizing the polyester by carrying out an esterification reaction of a dicarboxylic acid or its ester derivative and a diol compound in the presence of a titanium catalyst, before the solid phase polymerization. The synthesis of polyester is performed in the presence of titanium catalyst at 1-30 ppm, which corresponds to the amount of titanium atoms. EXAMPLE - Terephthalic acid (17.3 kg) and ethylene glycol (8.4 kg) were supplied to an esterification reaction vessel, then ethylene glycol solution of a titanium alkoxide compound (2 wt.%), and an ethylene glycol solution of magnesium acetate were added to the vessel. The esterification reaction vessel was adjusted to 250 degrees C and the pressure of 3x 105 (Pa). Then, it was confirmed that water was distilled by the esterification reaction, and then the reaction was performed for 3 hours. The obtained esterification reaction product was transferred, to a condensation polymerization reaction vessel, and ethylene glycol solution of trimethyl phosphate (25 mass%) was added. Then the temperature was gradually increased to 280 degrees C and the pressure was reduced to 20 Pa. When reaching a given stirring torque, the reaction system was purged with nitrogen, the pressure was returned to a normal pressure, and the condensation polymerization reaction was stopped. The polymer polyethylene terephthalate (PET) was discharged in cold water in the shape of a strand, and immediately cut to prepare pellets of the polymer. The polyethylene-2,6-naphthalate (PEN) was also obtained by polymerization using a stibium catalyst and formed into pellets. The resin pellets were charged in a container and solid phase polymerization was carried out, dried and then extruded, solidified, biaxially stretched, heat fixed, heat relaxed, and subjected to press processing to form films.