| 摘要 |
Provided is a polyester composition having polyester as a main component. The polyester composition is characterized by: comprising phosphoric acid and an alkali metal phosphate, with a phosphorous element content P (mol/t) at 1.8-5.0 mol/t with respect to the whole polyester composition; containing one type of metal element of either Mn and Ca, with the respective contents of divalent metal elements other than Mn and Ca of 5 ppm or lower with respect to the whole polyester composition; wherein, if the alkali metal element content with respect to the whole polyester composition is M1 (mol/t), and the total sum of the Mn element content and the Ca element content with respect to the whole polyester composition is M2 (mol/t), a metal content M (mol/t) and the phosphorous element content P (mol/t) in the polyester composition found using formula (i) satisfy formula (ii). (i) M=M1/2+M2 (ii) 1.1‰¤M/P‰¤3.0. Further provided is a film using the polyester compound, a sheet-like structure, an electric insulation sheet, and a solar cell back sheet for use with the polyester composition, and manufacturing method therefor. The polyester composition and the film, the sheet-like structure, the electric insulation sheet, and the solar cell back sheet using the polyester composition exhibit excellent heat resistance and moist heat resistance. |
