Triboluminescent inorganic material and a method for preparation thereof

Abstract

Provided by the invention is a novel synthetic inorganic triboluminescent material in the form of a powder, sintered block or thin film, of which the matrix phase is a piezoelectric crystalline material of a wurtzite structure such as zinc sulfide and the activator to serve as the center of luminescence is a transition metal element such as manganese, copper and rare earth elements in an amount of 0.01 to 10% by weight. The triboluminescent material is prepared by subjecting a powder blend of the matrix phase material and a thermally decomposable compound of the activator element first to a preparatory calcination treatment at 500 to 800.degree. C. and then, preferably in the form of a powder compact, to a second calcination treatment at 900 to 1700.degree. C., preferably, in vacuum under a sealed condition, when the material is liable to cause sublimation, or in an atmosphere of a reducing gas. The thus obtained triboluminescent material can be used as a source material for the formation of a thin film on a substrate, for example, by ion plating. The efficiency of the triboluminescence is increased by increasing the crystallinity of the material by controlling the conditions of film deposition and/or by undertaking a heat treatment of the thin film as deposited.

Dependencies are inferred from the claim text.