| abstract |
A varnish containing a charge-transporting organicnmaterial and a solvent is used as a charge-transportingnvarnish. The charge-transporting organic material isncomposed of a charge-transporting substance comprising ancharge-transporting monomer, or charge-transporting oligomernor polymer having a number average molecular weight of 200 ton500,000, or is composed of such a charge-transportingnsubstance and an electron- or hole-accepting dopant substance.nThe solvent contains at least one type of high-viscositynsolvent having a viscosity of 10 to 200 mPa·s at 20°C. Thencharge-transporting substance or the charge-transportingnorganic material is dissolved or uniformly dispersed in thensolvent. The varnish has a high uniform film formingncapability even in a system using a charge-transportingnsubstance of low molecular weight and a charge-acceptingndopant substance. When the varnish is used in, particularlynan OLED device or PLED device, excellent EL devicencharacteristics, namely a low drive voltage, a high luminancenefficiency, and a long life are realized. |