Self-Aligned Bank Formation of Organic Electroluminescent Devices Using Ink-Jet Printing Method

The self-aligned bank formation of organic electroluminescent devices using the ink-jet printing method was proposed and investigated. A solution of organic materials mixed with host and emission materials was printed on an indium–tin–oxide-coated glass substrate covered with an insulating polymer layer. The insulating material was dissolved in a solvent, and a mixture of organic materials was formed at the same position as that of the ink-jet-printed region, that is, a self-aligned organic electroluminescent device was realized. The diameter of the emission region was 200 µm and a luminance of 9,070 cd/m2 was obtained using an electrophosphorescent material.