According to the materials used in the production of polyester film and the production process classification.

According to the different raw materials and drawing processes used in the production of polyester film can be divided into the following two types.

1. Bidirectional Stretch Polyester film (BOPET)

General BOPET film is the use of light material (also known as large light material, that is, the raw material polyester chip titanium dioxide content of 0.1%, after drying, melting, extrusion, casting and vertical and horizontal stretching of high-grade film, widely used). BOPET film has the characteristics of high strength, good rigidity, transparency and high gloss. Odorless, tasteless, colorless, non-toxic, outstanding strength and toughness; Its tensile strength is 3 times that of PC film, nylon film, impact strength is 3 to 5 times that of BOPP film, has excellent wear resistance, folding resistance, pinhole resistance and tear resistance; The thermal shrinkage is very small, at 120℃, only 1.25% shrinkage after 15min; It has good antistatic property, easy to vacuum aluminization, and can be coated with PVDC to improve its heat sealing, barrier property and printing adhesion; BOPET also has good heat resistance, excellent cooking resistance, low temperature freezing resistance, good oil resistance and chemical resistance. BOPET film in addition to nitrobenzene, chloroform, benzyl alcohol, most chemicals can not make it dissolve. However, BOPET will be eroded by strong alkali, and should be paid attention to when using. BOPET film has low water absorption, good water resistance, and is suitable for packaging foods with high water content.

2. Unidirectional Stretch Polyester Film (CPET)

General CPET film is the use of semi-matting material (raw material polyester chips add titanium dioxide), after drying, melting, extrusion, casting and longitudinal stretching of the film, the lowest grade and price in polyester film, mainly used for pharmaceutical tablet packaging. Due to the use of less, manufacturers less large-scale production, accounting for about 5% of the polyester film field, Chinese enterprises are also less imported, the standard thickness of 150μm.