NOVELTY - The multilayer biaxially oriented white polyester film comprises a core layer (4.2), two outer layers (4.1, 4.3), a radical scavenger, and a coating that is obtained by coextrusion coating, extrusion coating, corona treatment under ambient air or gases, vacuum evaporation, plasma treatment or physicochemical vacuum deposition. The white polyester film contains titanium dioxide (TiO2) particles, has an intrinsic viscosity of 0.5-0.85 dl/g, 0.55-0.8 dl/g, 0.6-0.75 dl/g and 0.65-0.75, and a global planar sonic sheet tester modulus of 440-465 kgf/mm2, 445-465 kgf/mm2 and 450-465 kgf/mm2.    USE - The multilayer biaxially oriented white polyester film is useful in a back sheet laminate of solar or photovoltaic cell or battery (all claimed), which is useful on domestic or industrial building roof tops and for electric or electronic parts, where the polyester film is polyethylene terephthalate film, polyethylene naphthalate film or polybutylene terephthalate.    ADVANTAGE - The multilayer biaxially oriented white polyester film is cost-effective, exhibits improved adhesion properties, high opacity level, excellent whiteness and reflectance, increased hydrolysis resistance, good light stability, and enhanced antistatic, slip and winding performances, improves the mechanical integrity, electrical transduction efficiency and durability of the photovoltaic battery, and provides good protection to the battery.    DETAILED DESCRIPTION - The multilayer biaxially oriented white polyester film comprises a core layer (4.2), two outer layers (4.1, 4.3), a radical scavenger, and a coating that is obtained by coextrusion coating, extrusion coating, corona treatment under ambient air or gases, vacuum evaporation, plasma treatment or physicochemical vacuum deposition. The white polyester film contains titanium dioxide (TiO2) particles, has an intrinsic viscosity of 0.5-0.85 dl/g, 0.55-0.8 dl/g, 0.6-0.75 dl/g and 0.65-0.75, a global planar sonic sheet tester modulus of 440-465 kgf/mm2, 445-465 kgf/mm2 and 450-465 kgf/mm2, and a total thickness of 10-500 mu m, 20-300 mu m and 35-250 mu m, and further comprises a flame retardant. One of the core and outer layers includes polyethylene terephthalate having: an average molecular weight of 18500-40000, 19000-35000 and 20000-30000; an intrinsic viscosity of greater than 0.70 dL/g, greater than 0.75 dL/g, greater than 0.78 dL/g and 0.78-1.20 dL/g; and a carboxyl group content of less than 30 eq/T, less than 25 eq/T, less than 21 eq/T, less than 15 eq/T and 5-15 eq/T. The core layer includes TiO2 particles having concentration of 0.1-40 w/w.%, 0.5-30 w/w.%, 1-20 w/w.% and 2-10 w/w.%. A small endothermic peak temperature (Tmeta) measured on the film is 180-220 degrees C. A light stabilizer is added in one of the outer layers in a total concentration of 0.1-35 w/w.%, 0.2-25 w/w.%, 0.3-20 w/w.%, 0.4-10 w/w.% and 0.5-5 w/w.%. One of the outer layers contains TiO2 particles in a concentration of less than 5 w/w.%, less than 4 w/w.% and 0.01-3 w/w.%. No chalking phenomenon, represented by a powdering on the surface of the film, is observed before or after natural or accelerated ageing. An INDEPENDENT CLAIM is included for a method for manufacturing a multilayer biaxially oriented white polyester film.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic cross-sectional view of a multilayered white polyester film.    Outer layers (4.1, 4.3)    Core layer. (4.2)