Ceramics Art + Perception, Ceramics Technical, vol.34, pp.94-99, 2012 (AHCI)
Phosphors have great potential in several applications for devices and luminous
paints and have been widely studied. They are a kind of energy storing material that can absorb both ultraviolet (UV) and visible lights from the sunlight and
gradually release the energy in the dark at a certain wavelength. A phosphorescent
material, such as the ZnS matrix, has been well known as a long lasting phosphor but
did not show sufficient brightness and long phosphorescent behaviour.1–2 As is known,
strontium aluminates doped with divalent europium ions possess high quantum efficiency, long phosphorescence persistence and good stability, indicating their good
practical prospects. For specific dark vision applications involving signage, blackouts,
emergency rescue guidance systems and luminous watches, the phosphor with appreciable brightness and a long persistence duration for more than five hours is strongly
requested.3
The photo luminescent particles preferably consist of non-radioactive photo
luminescent pigments. Suitable pigments are formed from rare earth materials. They are
characterised by low toxicity, short excitation time, high brightness and long glow life.4