3M window film is designed to block or filter sunlight from entering through windows. If the film becomes scratched or is peeling, it should be removed before applying a new layer of film. Once saturated in soapy water for several hours, the film will simply peel off the window. Once the film is removed, a thin layer of adhesive may remain, which must also be removed.
Cut a plastic drop sheet or garbage bag to the size of the window, using scissors.
Fill a spray bottle with warm water and a squirt of any liquid soap, such as hand soap or liquid dish soap. Spray the 3M window film with the soapy water until it becomes saturated. Position the plastic drop sheet or garbage bag over the film and soapy water. This helps lock in the moisture.
Allow the soapy water to work into the film for eight hours, or overnight.
Lift the plastic sheet or garbage bag off the window. Beginning in any corner, gently peel back the 3M window film. If needed, lift the corner or any stuck pieces with a plastic scraper.
Spray any remaining window film or adhesive with a citrus- or ammonia-based window cleaning product. Use a rag or soft cloth to wipe away the adhesive or film.