U-V Filtering Glass
	Ultra Violet filtering within the covering is a specific protection guarding the art from the fading effects of ultra violet light (UV). Some pigments, dye based as well as watercolors, airbrush inks and many digital inks now popular in desktop publishing are unstable or fade in sunlight-even ambient sunlight. Glass companies offer a film-covered glass to block out ultraviolet light but it does not filter the extreme ends of the spectrum, which are the most damaging. In addition, glass breaks and could cut paper art, if breakage occurs.