1. The protective function of packaging materials is the most important, the most basic function, it can be no exaggeration to say that if the packaging of plastic film protection of goods is not reliable, then it loses the value of the packaging material.

2. Plastic film in the protection of the function of merchandise is multi-faceted, different products, different packaging, the focus of the functional requirements of plastics packaging film protection is different.

3. Reliable protection functions, including packaging, to prevent commercial leakage or external material destruction and pollution of packaging goods, directly reflecting the mechanical protection of plastic film function, performance indicators, mainly the mechanical strength of the film, such as tensile strength, tearing strength, impact strength and puncture strength.

4. Strength and plastic film bags and reliable protective products welding good condition, if the weld strength is insufficient, the weld will plastic film bags fatal weakness, and plastic bags of merchandise because of the loss of protective welding cracks.