Arylamine compound and organic electroluminescent element

Abstract

The purpose of the present invention is to provide, as a material for high-efficiency and high-durability organic EL elements, a material for organic EL elements, which has excellent hole injection / transport performance, electron blocking ability, high stability in a thin film state, and excellent durability, and to provide a high-efficiency and high-durability organic EL element using the compound. The present invention is an arylamine compound represented by general formula (1). (In the formula, Ar1, Ar2, Ar3 and Ar4 represent a substituted or unsubstituted aromatic hydrocarbon group or the like, L1 and L2 represent a divalent substituted or unsubstituted aromatic hydrocarbon group or the like, R1 to R7 represent a hydrogen atom or a heavy hydrogen atom or the like, m and n represent integers of 0 to 2, which may be the same as or different from each other, L1 represents a single bond when m is 0, and L2 represents a single bond when n is 0. )

Description

Technical field [0001] The present invention involves the compounds and components that are suitable for the organic electrical glow elements (hereinafter referred to as organic EL components) suitable for the optical components that are suitable for various display devices. Organic EL component. Background technique [0002] Organic EL components are spontaneous optical components. Therefore, compared with LCD components, it is bright and visual. It can be displayed sharply, so active research is conducted. [0003] In 1987, C.W.tang, Eastman Kodak, developed a layered structure component that divided various functions to various materials, which made organic EL elements using organic materials into practical components. They will be able to transmit electronics fluorescent body and organic objects that can be transmitted to the ground, and inject the charge of the two into the layer of the fluorescent body to glow, thereby using the voltage below 10V 2 The above high brightness...

AI Technical Summary

Problems solved by technology

However, although NPD has good hole-transporting ability, its glass transition temperature (Tg), which is an index of heat resistance, is as low as 96°C, and degradation of device characteristics due to crystallization occurs under high-temperature conditions (see, for example, Non-Patent Document 4)

[0010] In addition, in the aromatic amine derivatives described in the above-mentioned patent documents, the mobility of holes is 10 -3 cm 2 Compounds having excellent mobility above / Vs (for example, refer to Patent Document 1 and Patent Document 2), but due to insufficient electron blocking properties, there are problems such as a part of electrons passing through the light-emitting layer, and improvement in luminous efficiency cannot be expected, In order to further increase efficiency, materials with higher electron barrier properties, more stable thin films, and high heat resistance are sought

In addition, there are reports of highly durable aromatic amine derivatives (for example, refer to Patent Document 3), but they are used as charge transport materials used in electrophotographic photoreceptors, and there are no examples of their use as organic EL devices.

[0011] In order to solve this problem, arylamine compounds having a substituted carbazole structure and a triarylbenzene structure have been proposed as compounds having improved properties such as heat resistance and hole injection properties (for example, refer to Patent Document 4 and Patent Document 5), However, for devices using these compounds in the hole injection layer or hole transport layer, although improvements in device life, luminous efficiency, etc. have been achieved, it is still not sufficient, and further lower driving voltage and higher luminous efficiency are required. and longer life of components

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