First of all, the paper for making paper containers must be food-grade paper, which is mostly imported from Europe and the United States, and is the best grade in paper. Then, it is necessary to go through the film process and coat the oil-water resistant material on the paper before the subsequent molding step can be carried out.
After the film treatment, the desired pattern and color will be printed on the paper roll. The printing method can be divided into three ways: gravure plate, convex plate and flat plate. Intaglio plate cost is too high, now less used; Convex plate printing with paper rolls for continuous printing, the required printing volume is large. Lithography is the paper cut into pieces and then printed, suitable for the manufacture of small quantities of products. After the ink is finished, a layer of water and light treatment will be printed as protection.