Materials
Common pigments used in phosphorescent materials include zinc sulfide and strontium aluminate. Use of zinc sulfide for safety related products dates back to the 1930s. However, the development of strontium aluminate, with a luminance approximately 10 times greater than zinc sulfide, has relegated most zinc sulfide based products to the novelty category. Strontium aluminate based pigments are now used in exit signs, pathway marking, and other safety related signage.
- Phosphorescent pigments - comparison ZnS vs. aluminate
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left: Zinc sulfide, right: SrAl2O4
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pigments in the dark
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pigments in the dark after 4 min
- Phosphorescent pigments red and blue
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phosphorescent pigment red (Calcium sulfide)
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phosphorescent pigment red in the dark
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phosphorescent pigment blue (alkaline earth metal silicate )
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phosphorescent pigment blue in the dark
Read more about this topic: Phosphorescence
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