| 摘要 |
The present invention provides a biaxially oriented polyester film for a backsheet of photovoltaics which exhibits an excellent hydrolysis resistance and a low shrinkage rate. The present invention relates to a biaxially oriented polyester film for a backsheet of photovoltaics, comprising a polyester having an intrinsic viscosity of 0.65 to 0.90 dL/g as measured in a mixed solvent comprising phenol and tetrachloroethane at a mass ratio of 50/50 at 23°C, a carboxyl end group content of 0 to 26 equivalents/t, and a phosphorus element content of 0 to 170 ppm, which biaxially oriented polyester film has a shrinkage rate of not more than 0.8% as measured in a longitudinal direction thereof after subjected to heat treatment at 150°C for 30 min. |
