2. Materials used for paper-plastic packaging generally contain plastic components, mainly ethylene, and the treated coating can become plastic packaging film.

3. The name of "TPU" is thermoplastic polyurethane elastomer rubber, which can be softened under certain heat, but can remain unchanged at room temperature. When used in shoes, it has many functions of stable support. Features The main feature of TPU is that products with different hardness can be obtained by changing the ratio of various reaction components of TPU, and with the increase of hardness, its products still maintain good elasticity and wear resistance.