|MadSci Network: Chemistry|
Yes, an optical brightener could certainly be considered a dye if you consider what a dye is and does... A dye "stains" a material, and when light hits the surface of the material, certain wavelengths are absorbed by the dye and the rest of the wavelengths reflect (bounce off). Wavelengths that bounce off are the ones that reach our eyes and are detected (seen). An optical brightener is similar in a lot of ways: Its molecular structure is similar, and it will "stain" (stick to) certain materials. An optical brightener is basically a fluorescent dye: Light hits the optical brightener, in turn causing it to generate its own wavelengths of light that are radiated outward (emitted).
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