It Will Not Wash Off . It contains two layers of non-colored vinyl laminated together under intense pressure and heat. This material is soft and easily scratches, absorbs a wide range of gasses, U.V. rays, liquids, acids and other environmental elements. It will yellow and become brittle in time if you do not maintain it properly. UV protection added in the manufacturing process become less effective each day .
All manufacturers recommend first rinsing off the vinyl to remove the elements of nature and man.
Be careful not to touch the vinyl plastic window when grit appears. Use a very mild natural soap in bucket of cool water. With a soft clean cotton cloth, wash the vinyl window and immediately rinse with cool water. Repeat for the inside vinyl window. Dry your vinyl window with a clean, dry, cotton soft cloth or synthetic chamois.