According to the quality of polyester film

Different manufacturers can have different classification names according to the quality of polyester film. Chinese manufacturers are generally divided into superior products, first-class products and qualified products, while foreign manufacturers are generally classified into A-grade, B-grade and C-grade products. Among the products sold by general manufacturers, grade A products account for 97-98%, grade B products account for only 2-3%, and grade C products are substandard products and cannot be sold in the circulation field. The main reason is that the price of raw materials is high. Generally, manufacturers re-use them as raw materials or sell them as staple fibers to textile mills as textile raw materials. Foreign manufacturers sometimes sell their stocked film quarterly or half-yearly as Grade B products. This is a consistent practice of some manufacturers in Southeast Asian countries to reduce inventory.