EL ELEMENT AND ITS LUMINESCENT DISPLAY PATTERN RECORDING /ERASING/DISPLAYING METHOD

PROBLEM TO BE SOLVED: To obtain an EL element capable of reloading a luminescent pattern, driving a simple matrix, and realizing a low cost, high brightness, and long life by installing a conductive memory layer between an EL layer and either one electrode of facing electrodes, and using the conductive memory layer capable of forming a pattern by the difference between conductivities.

SOLUTION: Conductivity is varied by exposure, temperature change, and applied voltage. Conductivity can be varied in the direction increasing conductivity or in the direction decreasing conductivity, and use of a conductive memory having remaining conductivity even after exposure or heating is finished, i.e., having conductive memory effect is preferable. A conductive memory layer can actually be constituted by combining a charge transport material, a charge accepting material and others. A charge generating material, binder resin, antioxidant, and photo-deterioration inhibitor or sensitizing coloring matter may furthermore be mixed to the conductive memory layer.

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