|MadSci Network: Engineering|
You are correct white paint is best. Basically white is best because when it fluoresces it emits white light which is why whites appear "whiter that white"! If however you don't want to use white paint and still want to get a good glow the next best thing is to use a DAYGLO product or similar products that are impregnated with pigament that glows when black light is used. So you can have a blue paint that contains a fluorescent pigament that will do the job the white paint does. Obviously the disadvantage of this is cost as white paint is very cheap where as a speacialist paint such as dayglo is always going to be more expensive. As for the science bit, well here it comes: For an object to glow under black light (also known as ultraviolet light or UV light)the object must fluoresce. Fluorescence is defined as an atomic process in which an orbital electron is excited to a higher energy level by an external photon, spontaneously de-excites to a lower energy, and emits a characteristic low-energy photon. This process can continue, with low-energy photons emitted for each drop in electron energy,until the electron reaches the ground state.
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