| 摘要 |
PURPOSE:To operate a full-color display by a simple method by forming a luminescence layer combinationally dispersing at least one or several kinds of pigments in the luminescence layer and covering the visible light region widely to the utmost. CONSTITUTION:This device is constituted of a hole transportation layer 7, an electron transporting white luminescence layer 6, and a metal electrode 1 on an ITO transparent electrode 3. When plus DC voltage is applied to the ITO transparent electrode 3 and minus DC voltage is applied to the metal electrode 1, white luminescence is obtained. The hold transportation layer 7 is made of polyvinyl carbazole and has a high hole transportation property and no electron transportation property. The luminescence layer 6 contains small quantities of fluorescence dyes of an electron transporting oxadiazole derivative, tetraphenyl butadiene serving as the luminescence center, coumarin 6, DCM 1, and nile red in polymethyl methacrylate. These fluorescence dyes illuminate in blue, green, yellow, and red respectively, and white is obtained when they concurrently illuminate. |
