Phosphorescent pigments are materials that can absorb light and then re-emit it over time, creating a glow-in-the-dark effect. These pigments are commonly used in various applications, such as safety signs, watch dials, and toys. They work by storing energy from light sources, like sunlight or artificial light, and releasing it slowly in the dark. The glow from phosphorescent pigments can last from a few minutes to several hours, depending on the specific formulation and environmental conditions. Unlike fluorescent pigments, which emit light only while exposed to a light source, phosphorescent pigments continue to shine even after the light source is removed.