absorption rate is low, and the light transmittance can reach 88-92%. It is resistant to organic acids, alkalis, salts and lower alcohols, and soluble in esters and ketones.

3. PET hard sheet has good toughness and is a new type of material developed in recent years. With its excellent toughness, high strength, high transparency, and recyclable recycling, it is easy to burn. It does not produce harmful gases when burned. It is an environmentally friendly material and gradually bans PVC, but the price is high. It is suitable for high-grade plastic products. The plastic blister in Europe and the United States generally requires PET materials, but its high thermal melting point brings great difficulties to high-frequency packaging. In order to solve this problem, people are compounded on PET surface. The layer of PVC film, named PETG, but the price is higher. Mainly used in electronics, food, toys, color box window, collar, footwear packaging. The advantages are as follows: