When buying protective films, are you ever caught between choices? Worry not, as today's editor is here to reveal the essential attributes that a protective film should possess.

Protective film materials come in a variety of types; we won't list them all here. Let's take a three-layer PET protective film as an example to explain.

The three-layer PET protective film gets its name from the material PET. The PET high-pressure spray gun protective films we commonly see are treated for hardness, so when evaluating the quality of this type of protective film, the following criteria are used:

1. The better the light transmission, the higher the quality of the material. Light transmission cannot be discerned by the naked eye but requires a specialized instrument—the 3M Light Meter.

2. The surface hardening degree of the protective film represents the level of scratching that the protective film of this continuous UV curing equipment will experience when scraped. The higher the hardness, the greater the level of scratch resistance.

3. Check the protective film's adhesion by observing how quickly air is expelled. The faster the air is released, the stronger the adhesion of the film.

4. Inspect for the presence of crystal spots or rainbow patterns on the protective film; the more of these you find, the bigger the issue. Therefore, avoid selecting protective films with these problems.