WHITE POLYESTER FILM FOR SOLAR CELL, BACK-SEALING SHEET COMPRISING SAME FOR SOLAR CELL, AND SOLAR CELL MODULE

摘要

The object of the present invention is to provide a white polyester film for a solar cell that is excellent in transfer-mark concealment properties (properties that transferred irregularities are hard to be seen) while having high whiteness, and exhibiting good light resistance and hydrolysis resistance, a sealing sheet for a back surface of a solar cell and a solar cell module using the same. The white polyester film for a solar cell of the present invention has whiteness of 50 or more, an average reflectance of 50 to 95% in a range of wavelength of 400 to 800 nm, an acid value of 1 to 50 eq/ton, and a thickness of 30 to 380 µm, and the film has a multilayer structure in which a polyester resin layer containing inorganic fine particles in an amount of 10 to 38% by mass is disposed as at least one outermost layer, and a half-value width of protrusion distribution on a surface of the polyester resin layer is 200 to 1000 nm, the protrusion distribution being obtained by plotting the number density of protrusions with respect to protrusion height.