When you buy plastic sheets such as acrylics, polycarbonate sheets etc, they come with a paper/plastic protective film. Like in this image :
Protective Film for Acrylic Sheet PMMA Panel
You notice that there is no adhesive (at least not something tacky) that is present on the sheets, and there is no residue when the sheet is peeled off, I was wondering if anyone can shed some light on how these protective films are applied ?
The material is called "Electrostatic Protective Film".
It is manufactured by letting the plastic film cool in a strong electrostatic field: there are high-voltage electrodes on top and bottom of the plastic. This causes the polar molecules in the plastic to align so that one side of the film has a positive charge and the other side has a negative one.
This charge will persist quite long, and will keep the film adhered to the plastic sheet by electrostatic forces. However, because the electrostatic force is quickly reduced by distance, it is important that no dust gets between the protective film and the base plastic during manufacturing.
