Classification of polyester film in many ways, among them, according to the production of polyester film used for raw material and process can be divided into two categories.
1. biaxially oriented polyester film (BOPET for short), is the use of light materials drying, melting, extrusion, casting, and vertical and horizontal stretching of high-grade films, wide range of uses. BOPET film has strength high, and rigid good, and transparent, and gloss degrees high features; while can do no olfactory, and tasteless, and colorless, and nontoxic and highlight of strong toughness; its stretch strength is PC film, and nylon film of 3 times times, impact strength is BOPP film of 3-5 times, has very good of wear sex, and resistance folding sex, and resistance pinhole sex and anti-tear sex,; hot contraction sex minimum and has good of antistatic sex, easy for vacuum plating aluminum, can coated cloth PVDC, to improve its hot seal sex, and barrier sex and printing of adhesion ; BOPET has good heat resistance, excellent resistance to cooking, freezing, good oil resistance and chemical resistance, and so on. Outside of benzyl alcohol, chloroform, nitrobenzene, BOPET film, most of the dissolved chemicals can make it. However, BOPET is alkali erosion, should pay attention to. BOPET film low water absorption, good water resistance, suitable for packing foods high in water content.
2. tensile polyester film (referred to as CPET), is the use of semi dull (raw material of polyester slices add titanium dioxide), after drying, melting and longitudinally stretched film, extrusion, casting, grade and the lowest prices in the polyester film, mainly used in pharmaceutical tablet packaging. Due to the use of less and fewer factory mass production, Chinese enterprises are also less imports.