UV Absorbers

UV Absorbers and their Impact on Fading Overview This section provides a list of basic facts about the nature, use, importance, measurement, and effectiveness of ultraviolet (UV) absorbers as incorporated into the chemical composition of window films. Issues relating to product longevity and fade control are discussed. Please use it as needed as a reference guide in your sales presentations and discussions with your customers. UV Absorbers Ultraviolet light is stopped at the film by the use of ultraviolet absorbers in the film. Absorbers function by absorbing UV energy. All ultraviolet absorbers decrease in effectiveness over time in use. The type, amount, and location of the UV absorbers determine the relative stability of these absorbers. Many companies put ultraviolet absorbers into their adhesives instead of the film itself. We have found these absorbers to be much less stable than absorbers in the film. CPFilms impregnates the film structure with UV absorbers so that its designated films absorb 99% of all ultraviolet radiation between 280nm and 380nm. CPFilms accelerated testing indicates our films are still rejecting 98% of the ultraviolet radiation after 2000 hours of exposure in a xenon accelerated test chamber. This roughly equates to 3-5 years of normal exposure, depending on location. Similar testing has shown that films with absorbers only in the adhesive absorb between 96% and 98% of the radiation at installation and have dropped to as little as 93% after only 900 hours of exposure. After several years of exposure, there is very little ultraviolet protection left in these films. The CPFilms products will be protecting from UV long after the other products have lost their ability to screen UV. Fading Films do not eliminate fading—they reduce fading. Fading is only eliminated in a cool, dry totally dark environment. Most experts agree that the same amount of damage will be produced whether by high radiant light over a short period or a weak light over a longer period. Installing film alters the time it takes for the damage to occur. Certain fabrics and colors (dyes) are more susceptible to damage than other. Fade rates vary from item to item. Some fabrics and chemical dyes may be more susceptible to fading at specific wavelengths of light than others. Ultraviolet light, visible light, and heat are all significant contributors to fade. The most effective installation decreases all three of these elements. Curators are generally much more knowledgeable about their needs than the average homeowner. Museums are willing to exist in a much darker environment than the average individual, to protect their items. Papers, inks, natural plant dyes, and natural fibers are much more susceptible to fading and chemical breakdown than synthetics. Standard interior lighting can fade papers and inks. Most standard light fixtures emit ultraviolet radiation and are screened by special absorbing films for museum use. Hand-held UV meters are available through your distributor. Please contact your distributor for more information. Summary Note Fading is a complicated process but we have a great product that can significantly slow down the rate at which damage occurs. We will continue our search for better tools for you to use in showing these advantages to your customers. If you would like to read more about UV light degradation, try: Thomson, Garry. 1986. The Museum Environment. 2nd ed. Butterworth Series on Conservation in the Arts, Archaeology and Architecture. London: Butterworths. Standard reference work. Identifies issues and includes the scientific basis of sound practice. Covers light, humidity and air pollution.