The SrAl2O4: Eu2+, Dy3+ as a known strontium mono-aluminate europium dysprosium based phosphor widely used in paints and coating formulation as a photoluminescence pigment. It has two major drawbacks, un-proper dispersion in organic based paints and weak water and moisture resistance. To improve mentioned drawbacks, the surface coating of phosphor with polyethylene and polystyrene individually, and in combination using a solution technique was performed. The FT-IR spectrums showed that used polymers were coated on the phosphor properly. Also, the EDS spectra represented elemental carbon for the treated phosphors with different amounts. No regular trend was observed for elements ratios when the polyethylene content in coating layer reduced from 100 to 0%. Based on XRD patterns, the crystalline structure of the coated phosphors had not affected by polymeric coated layer. In SEM micrographs, the sharp and rough edges of the un-coated phosphor changed to a smooth and soft state for the coated phosphors. The brightness of the most coated phosphors was independent of the time and was not changed during 5 minutes after UV irradiation. This property makes the polymeric coated phosphors suitable for photoluminescence pigment in all kind of the paints and coatings.

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