Fluorochemical proprietary coatings create tension between the microspheres and the surrounding resins which repels the sphere to the surface. This "floating" effect positions the sphere to maximize the light transmission and enhance retroreflectivity of each sphere. Unless metallized spheres are at the surface of a formulation, light cannot travel through the clear hemisphere to bounce off the metallized shell and create a retroreflective effect. Metallized beads dispersed throughout the resin provide reduced benefit in terms of retroreflectivity. Placement at the surface allows for a reduction in the amount of microspheres needed to achieve the desired level of retroreflectivity.
Fluorochemical coatings increase hydrophobicity of retroreflective microspheres and are specifically designed for use in solvent-based (as opposed to aqueous) systems.