Easily tearable biaxially oriented polyester film

摘要

The present invention provides a biaxially oriented polyester film having a linearly tearable property at least in a longitudinal direction, and excellent in the producability at mass production scale, which can be produced from the mixture of polybutylene terephthalate containing 5 to 20% by weight of a polytetramethylene glycol (PTMG) unit having a molecular weight of 600 to 4,000 (modified PBT) and polyethylene terephthalate (PET) in a weight ratio (PET/modified PBT) of 70/30 to 95/5.