Conservators and chemists are studying the unstable pigments used in glow-in-the-dark and fluorescent art and fashion, including works by punk-era designer Stephen Sprouse, to understand why the colours fade and how they might be preserved. The research, presented this week at an American Chemical Society meeting in Chicago, matters because these bright pigments have been widely used since the mid-20th century in art, fashion, wartime equipment and safety gear, yet museums have lacked a clear scientific basis for conserving them as they degrade over time.

The work is led by photochemist Sarah Schmidtke Sobeck of The College of Wooster and conservation scientist Gregory Smith of the Indianapolis Museum of Art, who have collaborated for a decade, focusing partly on Sprouse pieces held in the museum's Newfields textile collection. Earlier studies found that the optical brighteners giving fluorescent pigments their vibrancy break down faster than the underlying dyes, making colours appear to dull even without pigment loss. Newer research into phosphorescent (glow-in-the-dark) pigments shows they are chemically distinct, relying on mineral-based and inorganic compounds rather than the organic dyes used in fluorescent pigments, with humidity identified as a key factor driving their deterioration.