High-luminosity stress-luminescent material

Abstract

Disclosed is a high-efficiency stress-luminescent material capable of emitting luminescence by receiving a mechanical stress such as compression, shearing and rubbing. The stress-luminescent material is an alkaline earth aluminate of a non-stoichiometric composition deficient in the content of the alkaline earth element by 0.01 to 20% by moles from stoichiometry. The efficiency of stress-luminescence emission can be further enhanced when the non-stoichiometric alkaline earth aluminate contains 0.01 to 10% by moles of rare earth metal ions or transition metal ions. The stress-luminescent material is prepared by subjecting a non-stoichiometric composite oxide of aluminum oxide and an alkaline earth oxide to a calcination treatment at 800 to 1700° C. in a reducing atmosphere.

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