Static window film can provide an easy and cost effective way to create privacy without blocking light coming in a window, and the designs available also provide for a home décor option that is quick to apply, can be cut to fit, and can be removed and reused at will.
There are two types of backing that come on static window film to prevent it from sticking to itself. Both are peel and stick; but one is a PE and silicone coated release paper, and the other is a fine PET film. The paper is probably the most familiar to people who have been using static cling film for years – however the second type is becoming more and more common as designs multiply and there arises the necessity to match designs and make cuts in appropriate places to allow for patterns.
Backing paper has going for it the fact that it is extremely easy to peel off, and it can be printed with a brand logo, materials data sheet, a cutting grid, or application instructions on the back. This is beneficial when trying to eliminate the need for paper printed inserts in the packaging and allows the film to be sold by the foot off of a roll if desired. However, the backing paper is hard to see through, making it difficult in cases when precise matching is desired and multiple cuts must be made to pattern match.
Backing film is only slightly harder than backing paper to remove (getting started in a corner may take a minute or two, but then it should peel free easily) and film has several advantages paper does not, including a see through quality that makes cutting and matching patterns a simple task without having to continually flip the film over and jigsaw the pieces. A grid can still be printed in faint colors to provide a straight edge guide.
A clear polyester release liner is the obvious choice when dealing with intricately designed window film.
However for basic projects using a simple tinted or colored film, the paper backing may be perfectly sufficient.
Of course, once a plant is set up to produce one or the other, the challenge becomes figuring out which would be the most beneficial, and in the end the more flexible option is probably best, meaning a clear backing film is likely the best possible solution for home décor and privacy films alike.