Pe protective film why crystal points

In PE protective film, if the present crystal point, then the detailed reasons, is due to: reason one: the material of the protective film used on cleanliness is not up to standard, perhaps by the dust pollution. Reason two: on the selection of raw materials, no choose appropriate, may be owe good compatibility between several kinds of raw materials, and then attack point. Three reasons: on the protective film processing, about the processing temperature, were not very good control, and then makes the material plasticizing, perhaps plasticizing excessive, crystal point and then attack. Reason 4: presented problems on processing equipment, quality problems with the device itself, perhaps equipment processing ability not line, etc.