Causes of Darkness on the Protective Film

- Jan 31, 2020-

With the rapid development of smart products, the popularization of smart products such as smart phones and smart TVs has greatly promoted the rapid development of the decoration industry, especially the protective film industry. However, when attaching a protective film, many times the protective film will appear dark, so what are the reasons for the protective film to appear dark? Here is a brief introduction for everyone.

(1) The longer the time, the more likely it is to form

The longer the time passes, the larger the contact surface between ordinary small bubbles and air, and the higher the possibility of shadow formation. Therefore, it is necessary to avoid the generation of small air bubbles when applying the film, and use a good quality, uniformly coated protective film, which can delay the appearance of shadows.


After the emulsifier migrates, shadows will be generated, and the surfactant will act as an external plasticizer in the coating film, making the coating film soft and elastic. It is advantageous if the plasticizer is evenly distributed during coating. However, due to the surface activity of the surfactant, the molecules will migrate out of the bulk phase and concentrate on the surface, which tends to be concentrated at the air interface, thus forming a dark shadow.

③ temperature

The protective film is held up at 80 ° C due to air bubbles, that is, the protective film has begun to tear slowly under high temperature. If the heat resistance or cohesion of the protective film adhesive is not good, It is very easy for the glue or shadow to appear around the protective film bubbles. Generally, the place where the shadows appear is the place where the protective film bubbles are formed.