Effect of a second protective layer in AC EL display structures on their characteristics

Abstract

Alternating current electroluminescent (AC EL) structures with yellow emission containing a second protective plasma polymer layer were investigated. An original hybrid technology and a plasma polymerization process were used for preparation of these structures.Plasma polymerization, used for preparation of the second protective layer of the AC EL structure, is a modern method for obtaining thin films, exhibiting many valuable practical properties: mechanical and thermal stability, chemical resistance, good adhesion to any substrate, etc. Moreover, by varying different plasma parameters of the plasma polymerization process, materials with different chemical compositions and different structures can be obtained. The monomer used was hexamethyldisiloxane. Thus, very stable thin protective polymer layers with thickness of about 0.5μm were synthesized.The inclusion of a protective silicon containing polymer layer in the composition of the AC EL structure led to an improvement of the brightness and the stability, as well as of the lifetime with about 5000h of operation. These AC EL structures can be used for displaying visible light information with various size, shape and configuration in different areas of style of living and industry.