Organic electroluminescence element, process for preparation of the same, and electrode film

A process for preparation of an organic electroluminescence element comprising the steps of:

• preparing a positive electrode substrate comprising a transparent substrate, a transparent positive electrode formed on the substrate, and a light-emitting organic material layer formed on the positive electrode;
• preparing a rolled negative electrode film comprising an outer resin film, a metal layer formed on the resin film, and an inner opaque negative electrode layer formed on the metal layer, the rolled negative electrode film being wound up around a core tube of metal or a core tube covered with a metal film with a tension of 2.5×105 to 4.0×107 N/m2 in vacuum or in an atmosphere of an inactive gas;
• unwinding the rolled negative electrode film;
• placing the unwound negative electrode film on the positive electrode substrate under the condition that the negative electrode is placed on the light-emitting organic material layer;
• and
• pressing the positive electrode substrate and the negative electrode film while heating the organic material layer to soften the organic material layer whereby causing the negative electrode film to adhere to the positive electrode substrate.