Blister packaging materials called hard film or film, commonly used are: PET (polyethylene terephthalate) hard film, PVC (polyvinyl chloride) hard film, PS (polystyrene) hard film.

PS hard film has low density, poor toughness, and is easy to burn. When it is burned, it will produce styrene gas (which is a harmful gas), so it is generally used to produce various industrial plastic trays.

PVC hard sheet has moderate toughness, is not easy to burn, and generates chlorine when it is burned, which has a certain impact on the environment. PVC is easy to heat and can be sealed by a sealing machine and high-frequency machine. It is the main raw material for producing transparent plastic products.

PET hard film has good toughness, high transparency, easy to burn, does not produce harmful gases when burning, and belongs to environmental protection materials, but its price is high, and it is suitable for high-grade plastic products. Generally, PET plastic film is required for plastic blister in European and American countries, but It is difficult to heat-seal, and it brings great difficulties to the packaging. To solve this problem, people use a material called PETG-glycol modified-polyethylene terephthalate. This material has both the advantages of PVC. Heat-sealing, but also PET's environmental protection and transparency, but the price is higher.