Polyester film is divided into biaxially stretched polyester film and unidirectionally stretched polyester film. Yongda shenghang's is biaxially stretched polyester film. Biaxially stretched polyester film: excellent wear resistance, folding resistance, pinhole resistance and tear resistance; The heat shrinkability is very small, with good antistatic property, and it is easy to vacuum aluminize. Unidirectional stretched polyester film: it is a film made of semi matting material through drying, melting, extrusion, casting and longitudinal stretching. It has the lowest grade and price in polyester film. It is mainly used for drug tablet packaging. Due to less usage and less large-scale production by manufacturers, it accounts for about 5 percent of the polyester film field. Chinese enterprises also import less, and the standard thickness is 150 μ m.
