# Each specialty colorant has a specific attribute that makes them stand out when compared to regular colorants and pigments. To be able to describe these attributes, the following definitions must be understood.1 Luminescence: Fluorescence and phosphorescence.
# Luminescent Colorant: A material that emits light (visible, IR or UV) upon suitable excitation, without becoming incandescent.
# Excitation: A means of causing a luminescent colorant to emit light.
# Fluorescence: The emission of light by a luminescent pigment under excitation (e.g., daylight fluorescent).
# Phosphorescence: The emission of light by a luminescent pigment after excitation has ceased (e.g., glow-in-the-dark).
# Thermochromic: Reversibly altering color upon exposure to a heat source.
# Photochromic: Reversibly altering color upon exposure to a uv rich light source.
There are many forms of energy that selected luminescent pigments can absorb and convert to luminescence, such as radioactive (radioluminescence); X-ray.