ORGANIC ELEMENT FOR ELECTROLUMINESCENT DEVICES

• Main Authors: GIESEN, DAVID, JOHN, PARTON, RICHARD, LEE, TANG, CHING, WAN
• Format: Patent
• Language: English; French
• Published: 23.06.2005
• Edition: 7
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; ADHESIVES; CHEMISTRY; DYES; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC CHEMISTRY; PAINTS; POLISHES

Disclosed is an electroluminescent device comprising a cathode, an anode, and located therebetween a light emitting layer (LEL) containing (1) a host material that comprises a N,N,N',N'-tetra-aromatic benzidine group substituted in at least one position ortho to the biphenyl linkage between the phenyl groups of the benzidine nucleus and (2) a phosphorescent light emitting material, wherein the triplet state energy of the benzidine nucleus is higher than the triplet state energy of the phosphorescent emitting material. L'invention concerne un dispositif électroluminescent comprenant une cathode, une anode et, placées entre ces dernières, une couche électroluminescente (LEL) contenant (1) un matériau hôte renfermant un groupe N,N,N',N'- tétra-aromatique benzidine substitué en au moins une position ortho par rapport à la liaison entre les groupes phényle du noyau benzidine et (2) un matériau électroluminescent phosphorescent, l'énergie d'état triplet du noyau benzidine étant supérieure à celle du matériau à émission phosphorescente.