The second reason is that the screen has residual micro-dust particles, which occasionally absorb suspended particles in the air.
If encounter this kind of situation first tear the face as far as possible stick to the protective layer, stick attachment work to stop down, with the adhesive tape tape sticky side gently will wool flocs, particles stick out (adhesive tape than adsorption layer gravity).Then continue to attach, used to remove wool, particles of tape can only be used once, the next time the need for tape again from the tape roll out.Be careful when sticking the film to the final edge. Bubbles are most likely to appear.This step and try not to use the card to wipe cloth, try to use both hands inclined to press the protective film, the film adsorption up slowly, try to make sure no bubbles, in the middle of edges don't try so hard, the entire film such as adsorption go up again after processing edges of the bubble, this time with a small blade gently push the air out of.