JP2006032758A - Organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting element improved in light emitting efficiency and durability. <P>SOLUTION: The organic electroluminescent element having a light emitting layer and at least one organic layer between an anode and a cathode comprises at least one organic layer containing at least one kind of periods 5 or 6 and a group 5 or 11 metal complex or a rare earth metal complex between the light emitting layer and the cathode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an organic electroluminescent element capable of emitting light by converting electric energy into light.

  An organic electroluminescence element (also referred to as a light-emitting element, an organic EL element, or an EL element in the present invention) has been actively researched and developed in recent years because it emits light with high luminance when driven at a low voltage. In general, an organic EL element is composed of a light-emitting layer or a counter electrode sandwiching a plurality of organic layers including a light-emitting layer (a layer containing an organic compound). Electrons injected from a cathode and holes injected from an anode are One that utilizes light emission from excitons generated by recombination in the light-emitting layer, or one that utilizes light emission from excitons of other molecules generated by energy transfer from the excitons. Such an organic electroluminescent element can display an image using light emitted from an organic layer by applying an electric field between a pair of electrodes having an organic layer.

  As a means for improving the driving durability of an organic electroluminescent device, a metal complex (for example, an Al complex that is in the third period and group 13 or a Zn complex that is in the fourth period and group 12 is used as a host material in the light emitting layer) ) Has been reported (for example, Patent Document 1), but further improvements are desired in terms of efficiency and durability.

As a means for improving the driving durability of the organic electroluminescent device, a means using a zirconium complex that is in the fifth period and the fourth group in the electron transport layer has been reported (for example, Patent Documents 2 and 3). Further improvements are desired in terms of durability.
JP 2002-305083 A JP 2001-43976 A JP 2001-76879 A

  An object of the present invention is to provide a light-emitting element having good luminous efficiency and durability by containing a specific metal complex in a light-emitting layer.

This object has been achieved by the following means.
<1>
An organic electroluminescence device having a light emitting layer and at least one organic layer between an anode and a cathode, wherein at least one kind of the fifth to sixth periods and the fifth group is disposed between the light emitting layer and the cathode. An organic electroluminescence device having at least one organic layer containing a metal complex of Group 11 to Group 11 or a rare earth metal complex.
<2>
The central metal of the metal complex is selected from the group consisting of iron, manganese, nickel, copper, molybdenum, ruthenium, rhodium, palladium, silver, indium, tin, antimony, rare earth metal, tungsten, rhenium, osmium, iridium, platinum, and gold. The organic electroluminescent element according to <1>, which is selected.
<3>
The organic electroluminescent element according to <1> or <2>, wherein the metal complex is an organometallic complex.
<4>
The metal complex is represented by the following general formula (1), the following general formula (2), the following general formula (3), the following general formula (4), the following general formula (5), or the following general formula (6). The organic electroluminescent element as described in any one of <1> to <3>, which is a compound.

In the formula, Q ¹¹ , Q ²¹ , Q ⁴¹ and Q ⁶¹ each represent a group forming a nitrogen-containing heterocycle, and Z ¹¹ , Z ²¹ , Z ³¹ , Z ⁴¹ , Z ⁵¹ and Z ⁶¹ each represent a linking group. , M ¹¹ , M ²¹ , M ³¹ , M ⁴¹ , M ⁵¹ , and M ⁶¹ each represent a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, ¹¹ , L ²¹ , L ³¹ , L ⁴¹ , L ⁵¹ , L ⁶¹ each represents a ligand, R ²¹ , R ³² , R ⁵² each represents a hydrogen atom or a substituent, and X ⁴¹ , X ⁵¹ , X ⁶¹ Each represents a substituted carbon atom or a substituted nitrogen atom. n ¹¹ , n ²¹ , n ³¹ , n ⁴¹ , n ⁵¹ , and n ⁶¹ each represent an integer of 0 to 2, and m ¹¹ , m ²¹ , m ³¹ , m ⁴¹ , m ⁵¹ , and m ⁶¹ each represent 1 to 4 An integer is represented, and m ¹² , m ²² , m ³² , m ⁴² , m ⁵² , and m ⁶² each represent an integer of 0 to 6.
<5>
The organic electroluminescent element according to any one of <1> to <4>, wherein the organic layer containing the metal complex is adjacent to the light emitting layer.
<6>
The organic electroluminescent element according to any one of <1> to <5>, further comprising an electron transport layer between the organic layer containing the metal complex and the cathode.
<7>
The organic electroluminescent element according to any one of <1> to <6>, wherein the organic layer containing the metal complex is a hole blocking layer.
<8>
The organic electroluminescent element according to any one of <1> to <7>, wherein the organic layer containing the metal complex is an electron transport layer.
<9>
The organic electroluminescence device according to any one of <1> to <8>, wherein an ionization potential (Ip value) of the metal complex is 5.9 eV or more.
<10>
The organic electroluminescent element according to any one of <1> to <9>, wherein the light emitting material in the light emitting layer is at least one phosphorescent light emitting compound.
<11>
<10> wherein the T ₁ value of the metal complex is 60 kcal / mol (251 kJ / mol) or more, and λmax (the maximum emission wavelength) of phosphorescence obtained from the phosphorescent compound is shorter than 550 nm. Organic electroluminescent element.
<12>
The organic electroluminescent element according to <10> or <11>, wherein the light emitting layer does not contain a fluorescent light emitting compound, and at least one phosphorescent light emitting compound substantially emits light.
<13>
The organic electroluminescent element according to <10> to <12>, wherein the phosphorescent compound is an iridium complex, a platinum complex, a rhenium complex, a palladium complex, a rhodium complex, or a rare earth complex.
<14>
The organic electroluminescent element according to <1> to <13>, wherein the metal complex is a compound represented by the following general formula (7).

In the formula, Q ⁷¹ represents a group that forms an aromatic ring, M ⁷¹ represents a metal ion of Group 5 to Group 11 or a metal ion of Period 5 to 6 in the periodic table, L ⁷¹ Represents a ligand, and Y ⁷¹ , Y ⁷² , Y ⁷³ , and Y ⁷⁴ each represent a substituted or unsubstituted carbon atom or a nitrogen atom. m ⁷¹ represents an integer of 1 to 4, m ⁷² represents an integer of 0 to 6.
<14>
The organic electroluminescent element according to <1> to <12>, wherein the metal complex is a compound represented by the following general formula (8).

In the formula, Q ⁸¹ represents a group that forms an aromatic ring, M ⁸¹ represents a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, and L ⁸¹ represents Represents a ligand, and Y ⁸¹ , Y ⁸² , Y ⁸³ and Y ⁸⁴ each represents a substituted or unsubstituted carbon atom or a nitrogen atom. X ⁸¹ represents an oxygen atom, a sulfur atom, or a substituted or unsubstituted nitrogen atom. m ⁸¹ represents an integer of 1 to 4, m ⁸² represents an integer of 0 to 6.
<15>
The organic electroluminescent element according to <1> to <12>, wherein the metal complex is a compound represented by the following general formula (9).

In the formula, Q ⁹¹ represents a group that forms an aromatic ring, M ⁹¹ represents a metal ion or a rare earth metal ion of Groups 5 to 11 and 5 to 6 in the periodic table, and L ⁹¹ represents Y ⁹¹ represents an oxygen atom, a substituted or unsubstituted carbon atom, or a substituted or unsubstituted nitrogen atom; Y ⁹² and Y ⁹³ represent a substituted or unsubstituted carbon atom or nitrogen, respectively. Represents an atom. m ⁹¹ represents an integer of 1 to 4, and m ⁹² represents an integer of 0 to 6.
<16>
The organic electroluminescent element according to <1> to <12>, wherein the metal complex is a compound represented by the following general formula (10).

In the formula, Q ¹⁰¹ represents a group forming an aromatic ring, M ¹⁰¹ represents a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, and L ¹⁰¹ represents Y ¹⁰¹ represents an oxygen atom, a substituted or unsubstituted carbon atom, or a substituted or unsubstituted nitrogen atom, Y ¹⁰² and Y ¹⁰³ represent a substituted or unsubstituted carbon atom or nitrogen, respectively. X ¹⁰¹ represents an oxygen atom, a sulfur atom, or a substituted or unsubstituted nitrogen atom. m ¹⁰¹ represents an integer of 1 to 4, and m ¹⁰² represents an integer of 0 to 6.
<17>
The organic electroluminescent element according to <1> to <12>, wherein the metal complex is a compound represented by the following general formula (11).

In the formula, Q ¹¹¹ represents a group that forms an aromatic ring, M ¹¹¹ represents a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, and L ¹¹¹ represents Represents a ligand, and Y ¹¹¹ , Y ¹¹² , and Y ¹¹³ each represents a substituted or unsubstituted carbon atom or a nitrogen atom. m ¹¹¹ represents an integer of 1 to 4, and m ¹¹² represents an integer of 0 to 6.
<18>
The organic electroluminescent element according to <1> to <12>, wherein the metal complex is a compound represented by the following general formula (12).

In the formula, Q ¹²¹ represents a group that forms an aromatic ring, M ¹²¹ represents a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, and L ¹²¹ represents Represents a ligand, Y ¹²¹ , Y ¹²² , and Y ¹²³ each represent a substituted or unsubstituted carbon atom or a nitrogen atom; X ¹²¹ represents an oxygen atom, a sulfur atom, or a substituted or unsubstituted nitrogen atom; To express. m ¹²¹ represents an integer of 1 to 4, and m ¹²² represents an integer of 0 to 6.

  ADVANTAGE OF THE INVENTION According to this invention, the organic electroluminescent element which shows high luminous efficiency (high brightness | luminance, high external quantum efficiency), and was excellent in durability can be provided.

  The present invention is an organic electroluminescent device having at least one organic layer including a light emitting layer between a pair of electrodes, and has at least one organic layer between the light emitting layer and the cathode in addition to the light emitting layer. In the organic layer, a metal complex containing metal ions or rare earth metal ions of Group 5 to Group 11 and Group 5 to Group 6 in the periodic table (hereinafter referred to as the metal complex of the present invention). In particular, the present invention relates to an organic electroluminescent element characterized by containing at least one kind of

  In the present invention, the function of the “layer containing the metal complex of the present invention” is not limited, but is preferably provided as an electron injection layer, an electron transport layer, or a hole blocking layer, more preferably an electron. A transport layer and a hole blocking layer are preferable, and a hole blocking layer is more preferable. In addition to the light emitting layer and the layer containing the metal complex of the present invention, the organic electroluminescent device of the present invention has a desired layer, for example, a hole transport layer, a hole injection layer, an electron injection layer, etc. depending on the use of the device. You may add suitably. Preferably anode / hole transport layer / light emitting layer / electron transport layer / cathode, more preferably anode / hole injection layer / hole transport layer / light emitting layer / hole block layer / electron transport layer / electron injection layer / cathode And more preferably anode / hole injection layer / hole transport layer / electron block layer / light emitting layer / hole block layer / electron transport layer / electron injection layer / cathode, and the electron injection layer and electron transport layer. The hole blocking layer and the electron blocking layer can appropriately be a layer containing the metal complex of the present invention.

  The concentration of the metal complex of the present invention in the “layer containing the metal complex of the present invention” is not particularly limited, but is preferably the main component (the component having the largest content) in the light emitting layer, and has a mass of 50 mass. % To 100% by mass is more preferable, 70% to 100% by mass is more preferable, 80% to 100% by mass is particularly preferable, and 90% to 100% by mass is most preferable.

The glass transition point of the metal complex of the present invention is preferably 100 ° C. or higher and 500 ° C. or lower, more preferably 110 ° C. or higher and 300 ° C. or lower, and further preferably 120 ° C. or higher and 250 ° C. or lower.
The metal complex of the present invention may be luminescent or non-luminescent, but it is preferable that it does not contribute to light emission in an actual device.

  The Ip of the metal complex of the present invention is preferably 5.9 eV or more, more preferably 6.0 eV or more, and even more preferably 6.1 eV or more.

  The metal contained in the metal complex of the present invention is not particularly limited as long as it is a metal or rare earth metal of Group 5 to Group 11 and Period 5 to 6 in the periodic table, but iron, manganese, nickel, Copper, molybdenum, ruthenium, rhodium, palladium, silver, indium, tin, antimony, rare earth metal, tungsten, rhenium, osmium, iridium, platinum, gold are preferred, rhodium, palladium, barium, cerium, thorium, gadolinium, rhenium, iridium Platinum is more preferable, rhodium, palladium, rhenium, iridium and platinum are more preferable, and rhodium and palladium are particularly preferable.

  The metal complex of the present invention is preferably a complex containing a multidentate ligand, a bidentate ligand coordinated by a nitrogen atom and a nitrogen atom, and a bidentate coordinated by a nitrogen atom and an oxygen atom. Ligand, bidentate ligand coordinated by oxygen atom and oxygen atom, bidentate ligand coordinated by carbon atom and nitrogen atom, or bidentate coordinated by carbon atom and oxygen atom It is more preferable that it is a complex containing the ligand of General formula (1), General formula (2), General formula (3), General formula (4), General formula (5), or General formula (6) It is more preferable that it is a compound represented by general formula (7), general formula (8), general formula (9), general formula (10), general formula (11), or general formula (12). Particularly preferred are the compounds represented.

The general formula (1) will be described. Q ¹¹ represents a group that forms a nitrogen-containing heterocycle (Q ¹¹ is a group that includes the atom to which the dotted line shown in the formula is bonded to form a nitrogen-containing heterocycle). Q ¹¹ may have a substituent on. As the substituent on Q ¹¹ , the following substituent group A is preferable.

(Substituent group A)
An alkyl group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, n-octyl, n- Decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.), an alkenyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms, For example, vinyl, allyl, 2-butenyl, 3-pentenyl, etc.), alkynyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, particularly preferably 2 to 10 carbon atoms, For example, propargyl, 3-pentynyl, etc.), aryl groups (preferably having 6 to 30 carbon atoms, more preferably A prime number of 6 to 20, particularly preferably a carbon number of 6 to 12, such as phenyl, p-methylphenyl, naphthyl, anthranyl, etc.), an acyl group (preferably having a carbon number of 1 to 30, more preferably a carbon number). 1 to 20, particularly preferably 1 to 12 carbon atoms, such as acetyl, benzoyl, formyl, pivaloyl, etc.), a sulfonyl group (preferably 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, Particularly preferably, it has 1 to 12 carbon atoms, such as mesyl, tosyl, etc.), a heterocyclic group (preferably 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, For example, nitrogen atom, oxygen atom, sulfur atom, specifically imidazolyl, pyridyl, quinolyl, furyl, thienyl, piperidyl, mol Rino, benzoxazolyl, benzimidazolyl, benzthiazolyl, carbazolyl group, azepinyl group, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 3 carbon atoms). 24, and examples thereof include trimethylsilyl, triphenylsilyl, and the like. These substituents may be further substituted.

The nitrogen-containing heterocycle formed by Q ¹¹ is preferably an aromatic nitrogen-containing heterocycle, more preferably a pyrrole ring, a pyrazole ring, an imidazole ring, a triazole ring, an oxazole ring, a thiazole ring, or an oxadiazole ring. , Thiadiazole ring, pyridine ring, pyrazine ring, pyrimidine ring and condensed rings thereof (for example, benzoxazole ring, quinoline ring, pyrazoimidazole ring), more preferably pyrazole ring, imidazole ring, pyridine ring, pyrazine ring , Pyrimidine rings and condensed rings thereof, more preferably pyridine rings and condensed rings thereof.

Z ¹¹ represents a linking group. Examples of the linking group include an alkyl linking group, an alkenyl linking group, an oxygen linking group, a sulfur linking group, a nitrogen linking group, a carbonyl linking group, a sulfonyl linking group, a sulfoxide linking group, an aryl linking group, and a heterocyclic linking group.

Z ¹¹ is preferably an alkyl linking group, an alkenyl linking group, a carbonyl linking group, an aryl linking group or an aromatic heterocyclic linking group, and more preferably an alkenyl linking group, a carbonyl linking group or an aryl linking group.

M ¹¹ represents a metal ion or a rare earth metal ion of Groups 5 to 11 and 5 to 6 in the periodic table. Represents the metal ions described in the metal contained in the metal complex constituting the host material of the present invention, iron ion, manganese ion, nickel ion, copper ion, molybdenum ion, ruthenium ion, rhodium ion, palladium ion, silver ion , Indium ion, tin ion, antimony ion, rare earth metal ion, tungsten ion, rhenium ion, osmium ion, iridium ion, platinum ion, gold ion are preferable, rhodium ion, palladium ion, barium ion, cerium ion, thorium ion, gadolinium Ion, rhenium ion, iridium ion and platinum ion are more preferable, rhodium ion, palladium ion, rhenium ion, iridium ion and platinum ion are more preferable, rhodium ion and palladium. On it is particularly preferred.

L ¹¹ represents a ligand. As ligands, for example, “Photochemistry and Photophysics of Coordination Compounds” published by Springer-Verlag H. Yersin in 1987, “Organic Metal Chemistry-Fundamentals and Applications”, published by Akio Yamamoto in 1982 And preferably include a halogen ligand (preferably a chlorine ligand or a fluorine ligand), a nitrogen-containing heterocyclic ligand (for example, bipyridyl, phenanthroline, phenylpyridine, pyrazolylpyridine, benzine). Imidazolylpyridine, etc.), diketone ligand, nitrile ligand, CO ligand, isonitrile ligand, phosphorus ligand (eg, phosphine derivatives, phosphite derivatives, phosphinin derivatives, etc.), carboxylic acid coordination More preferably a bidentate nitrogen-containing heterocyclic ligand (eg bipyridyl, phenanthroline, Phenyl pyridine, pyrazolyl pyridine, benzimidazolyl pyridine, picolinic acid ligand, and the like) and diketone ligands (for example, acetylacetone ligand). L ¹¹ is also preferably a ligand described in the general formulas (1) to (12) (a ligand in which m ^{11 to} m ¹²¹ are coordinated).

n ¹¹ represents an integer of 0 to 2. When n ¹¹ is 2, the plurality of Z ¹¹ may be the same or different. n ¹¹ is preferably 1 or 2.

m ¹¹ represents an integer of 1 to 4. m ¹¹ is preferably 1 to 3, and more preferably 1 or 2.

m ¹² represents an integer of 0 to 6. m ¹² is preferably 0 to 3, more preferably 0 to 2, and still more preferably 0 or 1.

The general formula (2) will be described. Q ²¹ , M ²¹ , L ²¹ , n ²¹ , m ²¹ and m ²² have the same meanings as Q ¹¹ , M ¹¹ , L ¹¹ , n ¹¹ , m ¹¹ and m ¹² , and the preferred ranges are also the same.

Z ²¹ represents a linking group. Examples of the linking group include an alkyl linking group, an alkenyl linking group, an oxygen linking group, a sulfur linking group, a nitrogen linking group, a carbonyl linking group, a sulfonyl linking group, a sulfoxide linking group, an aryl linking group, and a heterocyclic linking group. Z ²¹ may combine with R ²¹ to form a nitrogen-containing heterocycle (eg, pyrazole ring, imidazole ring, etc.).

Z ²¹ is preferably an alkyl linking group, an alkenyl linking group, a carbonyl linking group, an aryl linking group, an aromatic heterocyclic linking group, or a group that combines with R ²¹ to form a nitrogen-containing heterocyclic ring, more preferably An alkenyl linking group, a carbonyl linking group, an aryl linking group, or a group that combines with R ²¹ to form a nitrogen-containing heterocycle.

R ²¹ represents a hydrogen atom or a substituent. It may combine with Z ²¹ to form a nitrogen-containing heterocycle. Examples of the substituent represented by R ²¹ include alkyl groups, aryl groups, aromatic heterocyclic groups, acyl groups (eg, acetyl group, benzoyl group, trifluoroacetyl group), sulfonyl groups (methanesulfonyl group, pentafluorobenzene). A sulfonyl group, etc.), a hydroxy group, an alkoxy group, an amino group, and an imino group, and these may further have a substituent (for example, a group described as a substituent on Q ¹¹ ). R ²¹ is preferably an acyl group, a sulfonyl group, a group bonded to Z ²¹ to form a nitrogen-containing heterocyclic ring, more preferably a group capable of forming a nitrogen-containing heterocyclic ring bonded to Z ^21.

The general formula (3) will be described. Z ³¹ , M ³¹ , L ³¹ , n ³¹ , m ³¹ and m ³² have the same meanings as Z ¹¹ , M ¹¹ , L ¹¹ , n ¹¹ , m ¹¹ and m ¹² , respectively, and preferred ranges are also the same.

R ³² represents a hydrogen atom or a substituent, and examples of the substituent include the groups described above for the substituent on Q ¹¹ . R ³² is preferably an alkyl group, an aryl group, an aromatic heterocyclic group, an alkoxy group or an amino group, more preferably an alkyl group, an aryl group or an aromatic heterocyclic group, further preferably an alkyl group.

The general formula (4) will be described. Q ⁴¹ , M ⁴¹ , L ⁴¹ , n ⁴¹ , m ⁴¹ , and m ⁴² are synonymous with Q ¹¹ , M ¹¹ , L ¹¹ , n ¹¹ , m ¹¹ , and m ¹² , respectively, and the preferred ranges are also the same.

Z ⁴¹ represents a linking group. Examples of the linking group include an alkyl linking group, an alkenyl linking group, an oxygen linking group, a sulfur linking group, a nitrogen linking group, a carbonyl linking group, a sulfonyl linking group, a sulfoxide linking group, an aryl linking group, and a heterocyclic linking group. Z ⁴¹ may combine with X ⁴¹ to form a ring structure (eg, a benzene ring, a cyclohexene ring, a pyridine ring, etc.). Z ⁴¹ is preferably an alkyl linking group, an alkenyl linking group, a carbonyl linking group, an aryl linking group, an aromatic heterocyclic linking group, or a group that combines with X ⁴¹ to form a ring structure, and more preferably an alkenyl linking group. Group, a carbonyl linking group, an aryl linking group, or a group that combines with X ⁴¹ to form a ring structure, and more preferably a group that combines with X ⁴¹ to form an aromatic ring.

X ⁴¹ represents a substituted carbon atom or a substituted nitrogen atom. Examples of the substituent on the carbon atom include the group described for the substituent on Q ^11. Examples of the substituent on the nitrogen atom include the group described for R ²¹ . It may combine with Z ⁴¹ to form a ring structure (eg, benzene ring, cyclohexene ring, pyridine ring, etc.).

X ⁴¹ is preferably a group that forms a ring structure by bonding to a substituted carbon atom, Z ^41, and more preferably a group that forms an aromatic ring by bonding to Z ⁴¹ .

The general formula (5) will be described. R ⁵² , Z ⁵¹ , X ⁵¹ , M ⁵¹ , L ⁵¹ , n ⁵¹ , m ⁵¹ , and m ⁵² are R ³² , Z ⁴¹ , X ⁴¹ , M ⁴¹ , L ⁴¹ , n ⁴¹ , m ⁴¹ , and m ⁴² , respectively. It is synonymous and the preferable range is also the same.

The general formula (6) will be described. M ⁶¹ , L ⁶¹ , X ⁶¹ , n ⁶¹ , m ⁶¹ , and m ⁶² are the same as M ¹¹ , L ¹¹ , X ⁴¹ , n ¹¹ , m ¹¹ , and m ¹² , respectively, and the preferred ranges are also the same.

Q ⁶¹ represents a group forming a nitrogen-containing heterocycle. Q ⁶¹ may further have a substituent (examples of substituents, preferred ranges thereof are the same as the substituents on Q ¹¹ ). The ring formed by Q ⁶¹ is preferably a pyrazole ring (or a condensed ring thereof) or a triazole ring, and more preferably a pyrazole ring.

The general formula (7) will be described. M ⁷¹ , L ⁷¹ , m ⁷¹ and m ⁷² have the same meanings as M ¹¹ , L ¹¹ , m ¹¹ and m ¹² , respectively, and the preferred ranges are also the same.

Q ⁷¹ represents a group that forms an aromatic ring. The aromatic ring formed by Q ^71, an aromatic hydrocarbon ring (benzene ring, naphthalene ring, phenanthrene ring, anthracene ring, triphenylene ring, pyrene ring, etc.), aromatic nitrogen-containing hetero ring (pyridine ring, pyrazine ring, A pyrrole ring, a pyrazole ring, a quinoline ring, an indole ring, etc.), an aromatic sulfur-containing heterocycle (thiophene ring, benzothiophene ring, etc.), and an aromatic oxygen-containing heterocycle (furan ring, etc.), an aromatic hydrocarbon ring, An aromatic nitrogen-containing heterocycle is more preferable, and an aromatic hydrocarbon ring is more preferable.

Y ⁷¹ , Y ⁷² , Y ⁷³ and Y ⁷⁴ each represent a substituted or unsubstituted carbon atom or a nitrogen atom. Substituents on the carbon atom may be bonded to form a condensed ring structure (eg, quinoline ring, isoquinoline ring, etc.). Y ⁷¹ , Y ⁷² , Y ⁷³ and Y ⁷⁴ are preferably substituted or unsubstituted carbon atoms.

The general formula (8) will be described. Q ⁸¹ , M ⁸¹ , L ⁸¹ , Y ⁸¹ , Y ⁸² , Y ⁸³ , Y ⁸⁴ , m ⁸¹ , and m ⁸² are Q ⁷¹ , M ⁷¹ , L ⁷¹ , Y ⁷¹ , Y ⁷² , Y ⁷³ , Y ⁷⁴ , respectively. It has the same meaning as m ^71, m ^72, and the preferred range is also the same.

X ⁸¹ represents an oxygen atom, a sulfur atom, or a substituted or unsubstituted nitrogen atom, preferably an oxygen atom or a substituted nitrogen atom (a substituted acyl group or a substituted sulfonyl group is preferred as a substituent on the nitrogen atom), oxygen Atoms are more preferred.

The general formula (9) will be described. Q ⁹¹ , M ⁹¹ , L ⁹¹ , m ⁹¹ and m ⁹² have the same meanings as Q ⁷¹ , M ⁷¹ , L ⁷¹ , m ⁷¹ and m ⁷² , respectively, and the preferred ranges are also the same.

Y ⁹¹ represents an oxygen atom, a substituted or unsubstituted carbon atom (the substituent on the carbon atom is preferably an alkyl group, an aryl group or an aromatic heterocyclic group), or a substituted or unsubstituted nitrogen atom. A nitrogen atom (an alkyl group, an aryl group or an aromatic heterocyclic group is preferred as a substituent on the nitrogen atom) is preferable.

Y ⁹² and Y ⁹³ each represent a substituted or unsubstituted carbon atom or a nitrogen atom. A substituent on a carbon atom may be bonded to form a condensed ring structure (benzo condensed ring, pyridine condensed ring, etc.). Y ⁹² and Y ⁹³ are preferably a substituted carbon atom, and it is preferred that a substituted carbon atom and a substituent on the carbon atom are bonded to form an aromatic ring.

The general formula (10) will be described. Q ¹⁰¹ , M ¹⁰¹ , L ¹⁰¹ , Y ¹⁰¹ , Y ¹⁰² , Y ¹⁰³ , X ¹⁰¹ , m ¹⁰¹ , and m ¹⁰² are Q ⁷¹ , M ⁸¹ , L ⁷¹ , Y ⁹¹ , Y ⁹² , Y ⁹³ , X ⁸¹ , It has the same meaning as m ^71, m ^72, and the preferred range is also the same.

The general formula (11) will be described. Q ¹¹¹ , M ¹¹¹ , L ¹¹¹ , m ¹¹¹ , and m ¹¹² are synonymous with Q ⁷¹ , M ⁷¹ , L ⁷¹ , m ⁷¹ , and m ⁷² , respectively, and preferred ranges are also the same.

Y ¹¹¹ , Y ¹¹² and Y ¹¹³ each represent a substituted or unsubstituted carbon atom or a nitrogen atom, and a substituted or unsubstituted carbon atom is preferred.

The general formula (12) will be described. Q ¹²¹ , M ¹²¹ , L ¹²¹ , Y ¹²¹ , Y ¹²² , Y ¹²³ , X ¹²¹ , m ¹²¹ , and m ¹²² are Q ⁷¹ , M ⁷¹ , L ⁷¹ , Y ¹¹¹ , Y ¹¹² , Y ¹¹³ , X ⁸¹ , respectively. It has the same meaning as m ^71, m ^72, and the preferred range is also the same.

  In addition to the above, the compounds described in the general formulas (1) to (10) described in JP-A No. 2001-247859 can also be suitably used as the metal complex of the present invention.

The light emitting layer of the organic electroluminescent element of the present invention is preferably formed from a light emitting material and a host material.
Here, the host material is a material other than the fluorescent agent and the amplifying agent among the materials forming the light emitting layer. The function of dispersing and holding the fluorescent agent and the amplifying agent in the layer, the anode and the hole transport layer The function of receiving holes from the cathode, the function of receiving electrons from the cathode, the electron transport layer, etc., the function of transporting holes or electrons, the function of providing a field for recombination of holes and electrons, and the excitons generated by recombination A material having at least one function among the function of transferring the energy of the light to the light emitting material and the function of transporting holes or electrons to the light emitting material.

  The host material is preferably stable with respect to electrochemical oxidation or reduction (preferably oxidation and reduction) because a cation radical and / or an anion radical is generated in terms of its function. In addition, when recombination occurs on the host material, a singlet and triplet excited state of the host material is generated, and therefore, it is preferable that decomposition from a singlet and triplet excited state hardly occurs. In addition, since material decomposition and thin film destruction due to heat generated during driving are one of the major causes of deterioration of the device, the host material is also a material that is stable against heat and can remain amorphous up to high temperatures. Preferably there is.

  Although it does not specifically limit as host material, Compound (1-1)-(1-34) as described in Unexamined-Japanese-Patent No. 2003-27048, Compound (A-1)-(A-33) as described in Unexamined-Japanese-Patent No. 2002-1000047 , (B-1) to (B-62), (C-1) to (C-72), (D-1) to (D-75), (E-1) to (E-5), Exemplified compounds 1-60 described in JP-A-2002-193952, compounds 1-381 described in JP-A-2002-319491, compounds 1-37 described in JP-A-2000-119644, compounds 1- 1 described in JP-A-2003-217856 58, compounds (I-1) to (I-12) described in Japanese Patent Application No. 2002-241663, and compounds (I-1) to (I-16) and (II-1) described in Japanese Patent Application No. 2002-241662 (II-9), described in Japanese Patent Application No. 2002-252803 Compounds 1 to 26, Compounds 1 to 82 described in JP-A No. 2002-38141, Compounds 1 to 47 described in JP-A No. 2001-24758, Compounds 1 to 99 described in JP-A No. 2001-192653, JP-A No. 2001-284051 Compounds (HT-1) to (HT-20) described in JP-A-2002-140589, compounds (H-1) to (H-24) described in JP-A-2002-140589, and compounds (H-1 described in JP-A-2002-140590) ) To (H-26), compounds (E-1) to (E-66) described in JP-A No. 2002-338579, compounds (E-1) to (E-53) described in JP-A No. 2002-356589, Compounds (1-1) to (1-44) described in JP-A No. 2001-192651, Compounds (1-1) to (1-30) and (2-1) to (2) described in JP-A No. 12-351966 -22), (3-1) (3-13), (4-1) to (4-35), (5-1) to (5-8), and compounds (1-1) to (1-26) described in JP-A No. 2001-192652 In addition, compounds (H-1) to (H-38) described in JP-A No. 2002-305084 and complex host materials described in Japanese Patent Application No. 2003-285755 are preferably used.

  The light emitting material of the present invention will be described. The light emitting material is at least one compound that has a function of substantially emitting light in the light emitting layer, and the light emission may be fluorescent, phosphorescent, or both. At least one phosphorescent compound that substantially emits phosphorescence is preferred. The organic electroluminescent element of the present invention is more preferably an element in which the light emitting layer does not contain a fluorescent light emitting compound and at least one phosphorescent light emitting compound substantially emits light.

  The concentration of the light emitting material in the light emitting layer is not particularly limited, but is preferably equal to or less than the host material that is the main component, more preferably 0.1% by mass or more and 50% by mass or less, and 0.2% by mass. % To 30% by mass is more preferable, 0.3% to 20% by mass is particularly preferable, and 0.5% to 10% by mass is most preferable.

  The phosphorescent compound is not particularly limited, but is preferably a transition metal complex, more preferably an iridium complex, a platinum complex, a rhenium complex, a ruthenium complex, a palladium complex, a rhodium complex, or a rare earth complex, and more preferably an iridium complex or a platinum complex. . Further, orthocarbometalated iridium complexes having a difluorophenylpyridine ligand described in JP-A-2002-235076, JP-A-2002-170684, Japanese Patent Application No. 2001-239281, and Japanese Patent Application No. 2001-248165 are preferable.

  Also, US 6303238 B1, US 6097147, WO 00/57676, WO 00/70655, WO 01/08230, WO 01/39234 A2, WO 01/41512 A1, WO 02/02714 A2, WO 02/15645 A1, JP 2001 -247859, Japanese Patent Application No. 2000-33561, Japanese Patent Application No. 2002-117978, Japanese Patent Application No. 2001-248165, Japanese Patent Application No. 2002-233501, Japanese Patent Application No. 2001-239281, Japanese Patent Application No. 2002-170684, Japanese Patent Application Laid-Open No. 2002-226495, Japanese Patent Application Laid-Open No. 2002-226495. 2002-234894, JP-A-2001-247659, JP-A-2001-298470, JP-A-2002-173675, JP-A-2002-203678, JP-A-2002-203679, etc. A phosphorescent compound can also be used suitably.

  The phosphorescence lifetime (room temperature) of the phosphorescent compound of the present invention is not particularly limited, but is preferably 1 ms or less, more preferably 100 μs or less, and even more preferably 10 μs.

In the organic EL device of the present invention, the host material and the phosphorescent compound have a T ₁ value (the lowest triplet excited state energy value) of 60 kcal / mol (251 kJ / mol) or more, and from the phosphorescent compound. It is preferable that λmax (emission maximum wavelength) of the obtained phosphorescence is shorter than 550 nm, the T ₁ value of the host material and the phosphorescent compound is 62 kcal / mol (259 kJ / mol) or more, and More preferably, the λmax (maximum emission wavelength) of phosphorescence obtained from the phosphorescent compound is shorter than 500 nm, and the T ₁ value of the host material and phosphorescent compound is 65 kcal / mol (272 kJ / mol). In addition, the λmax (maximum emission wavelength) of phosphorescence obtained from the phosphorescent compound is 480 nm or less. Theft is more preferable.

  The Ip value of the metal complex of the present invention is preferably 5.9 eV or more, more preferably 6.0 eV or more, and even more preferably 6.1 eV or more.

  It is also preferable that the light emitting device of the present invention has at least two kinds of host materials. The use of two or more types of host materials is particularly advantageous in terms of durability.

  The metal complex, the host material, and the light emitting material of the present invention may be a low molecular compound, and an oligomer compound or a polymer compound (weight average molecular weight (polystyrene conversion) is preferably 1000 to 5000000, more preferably 2000 to 1000000, More preferably, it is 3000 to 100,000. In the case of a polymer compound, structures represented by the general formulas (1) to (12) may be included in the polymer main chain, or may be included in the polymer side chain. In the case of a polymer compound, it may be a homopolymer compound or a copolymer. The metal complex, host material, and light emitting material of the present invention are preferably low molecular compounds.

  next. Although the compound example of the metal complex of this invention is shown, this invention is not limited to this. In the compound examples, “Ph” represents a phenyl group.

  The compound of the present invention can be synthesized by various known methods.

  The organic EL element of the present invention is not particularly limited as long as it satisfies the requirements of the present invention, such as a system, a driving method, and a usage form.

  The method for forming the organic layer of the organic EL device containing the metal complex of the present invention is not particularly limited, but resistance heating vapor deposition, electron beam, sputtering, molecular lamination method, coating method (spray coating method, dip coating) Method, impregnation method, roll coat method, gravure coat method, reverse coat method, roll brush method, air knife coat method, curtain coat method, spin coat method, flow coat method, bar coat method, micro gravure coat method, air doctor coat , Blade coating method, squeeze coating method, transfer roll coating method, kiss coating method, cast coating method, extrusion coating method, wire bar coating method, screen coating method, etc.), inkjet method, printing method, transfer method, etc. are used Resistance heating vapor deposition in terms of characteristics and manufacturing, Computing method, a transfer method is preferable.

  The organic EL device of the present invention may have a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, a protective layer, etc. in addition to the light emitting layer, and each of these layers has other functions. It may be provided. Various materials can be used for forming each layer.

  The light-emitting element of the present invention can improve the light extraction efficiency by various known devices. For example, when the substrate surface shape is processed (for example, a fine uneven pattern is formed), or when ITO is used as an electrode, the refractive index of the substrate / ITO layer / organic layer is controlled. By controlling the film thickness of the organic layer, etc., it is possible to improve light extraction efficiency and external quantum efficiency.

  The light emitting element of the present invention takes out light emission from the cathode side, so-called top emission method (see Japanese Patent Application Laid-Open Nos. 2003-208109, 2003-248441, 2003-257651, and 2003-282261). It may be.

  In the light emitting device of the present invention, the device may be formed by providing at least one electrode on the substrate. In this case, the substrate used in the light-emitting device of the present invention is not particularly limited, but inorganic materials such as yttrium-stabilized zirconia and glass, polyethylene terephthalate, polybutylene terephthalate, polyester such as polyethylene naphthalate, polyethylene, polycarbonate, High molecular weight materials such as polyethersulfone, polyarylate, allyl diglycol carbonate, polyimide, polycycloolefin, norbornene resin, poly (chlorotrifluoroethylene), teflon, polytetrafluoroethylene-polyethylene copolymer may be used. .

  The organic electroluminescent element of the present invention may be used in combination with a singlet blue light emitting element. For example, the light emitting element of the present invention and the singlet blue light emitting element may be arranged in a pixel shape or a stripe shape to form a multicolor display or a full color display.

  The light emitting layer of the organic electroluminescent element of the present invention may have at least one laminated structure. The number of stacked layers is preferably 2 or more and 50 or less, more preferably 4 or more and 30 or less, and still more preferably 6 or more and 20 or less.

  The thickness of each layer constituting the stack is not particularly limited, but is preferably 0.2 nm or more and 20 nm or less, more preferably 0.4 nm or more and 15 nm or less, further preferably 0.5 nm or more and 10 nm or less, and particularly preferably 1 nm or more and 5 nm or less. .

  The light emitting layer of the organic electroluminescent element of the present invention may have a host material, a light emitting material, and other materials, and a domain structure (a micro region composed of a host material, a material such as a light emitting material, and a mixture thereof) made of each. Good. The light emitting layer may have a plurality of domain structures made of the same material, or may have a plurality of domain structures made of different materials. The diameter of each domain is preferably from 0.2 nm to 10 nm, more preferably from 0.3 nm to 5 nm, still more preferably from 0.5 nm to 3 nm, and particularly preferably from 0.7 nm to 2 nm.

  The anode supplies holes to a hole injection layer, a hole transport layer, a light emitting layer, and the like, and a metal, an alloy, a metal oxide, an electrically conductive compound, or a mixture thereof can be used. Is a material having a work function of 4 eV or more. Specific examples include conductive metal oxides such as tin oxide, zinc oxide, indium oxide and indium tin oxide (ITO), metals such as gold, silver, chromium and nickel, and these metals and conductive metal oxides. Inorganic conductive materials such as copper iodide and copper sulfide, organic conductive materials such as polyaniline, polythiophene, and polypyrrole, and laminates of these with ITO, preferably conductive metals It is an oxide, and ITO is particularly preferable from the viewpoint of productivity, high conductivity, transparency, and the like. Although the film thickness of the anode can be appropriately selected depending on the material, it is usually preferably in the range of 10 nm to 5 μm, more preferably 50 nm to 1 μm, still more preferably 100 nm to 500 nm.

As the anode, a layer formed on a base material such as soda lime glass, alkali-free glass, or transparent resin substrate is usually used. When glass is used, it is preferable to use non-alkali glass as the material in order to reduce ions eluted from the glass. Moreover, when using soda-lime glass, it is preferable to use what gave barrier coatings, such as a silica. The thickness of the substrate is not particularly limited as long as it is sufficient to maintain the mechanical strength, but when glass is used, a thickness of 0.2 mm or more, preferably 0.7 mm or more is usually used.
Various methods are used for producing the anode depending on the material. For example, in the case of ITO, an electron beam method, a sputtering method, a resistance heating vapor deposition method, a chemical reaction method (sol-gel method, etc.), a coating of a dispersion of indium tin oxide, etc. A film is formed by this method.
The anode can be subjected to cleaning or other treatments to lower the drive voltage of the element or increase the light emission efficiency. For example, in the case of ITO, UV-ozone treatment, plasma treatment, etc. are effective.

The cathode supplies electrons to the electron injection layer, the electron transport layer, the light emitting layer, etc., and the adhesion, ionization potential, stability, etc., between the negative electrode and the adjacent layer such as the electron injection layer, electron transport layer, light emitting layer, etc. Selected in consideration of As a material for the cathode, a metal, an alloy, a metal halide, a metal oxide, an electrically conductive compound, or a mixture thereof can be used. Specific examples include an alkali metal (for example, Li, Na, K, etc.) and its fluoride. Or oxides, alkaline earth metals (eg, Mg, Ca, etc.) and fluorides or oxides thereof, gold, silver, lead, aluminum, sodium-potassium alloys or their mixed metals, lithium-aluminum alloys or their mixtures Examples thereof include metals, magnesium-silver alloys or mixed metals thereof, rare earth metals such as indium and ytterbium, preferably materials having a work function of 4 eV or less, more preferably aluminum, lithium-aluminum alloys or mixed metals thereof. , Magnesium-silver alloys or mixed metals thereof. The cathode can take not only a single layer structure of the compound and the mixture but also a laminated structure including the compound and the mixture. For example, a laminated structure of aluminum / lithium fluoride and aluminum / lithium oxide is preferable. The film thickness of the cathode can be appropriately selected depending on the material, but is usually preferably in the range of 10 nm to 5 μm, more preferably 50 nm to 1 μm, still more preferably 100 nm to 1 μm.
For production of the cathode, methods such as an electron beam method, a sputtering method, a resistance heating vapor deposition method, a coating method, and a transfer method are used, and a metal can be vapor-deposited alone or two or more components can be vapor-deposited simultaneously. Further, it is possible to simultaneously deposit a plurality of metals to form an alloy electrode, or a previously prepared alloy may be deposited.
The sheet resistance of the anode and the cathode is preferably low, and is preferably several hundred Ω / □ or less.

The material of the light emitting layer is a function capable of injecting holes from the anode or hole injection layer, hole transport layer and cathode or electron injection layer, electron transport layer when an electric field is applied, Any material can be used as long as it can form a layer having a function of transferring injected charges and a function of emitting light by providing a recombination field of holes and electrons, such as benzoxazole, benzimidazole, and benzothiazole. , Styrylbenzene, polyphenyl, diphenylbutadiene, tetraphenylbutadiene, naphthalimide, coumarin, perylene, perinone, oxadiazole, aldazine, pyralidine, cyclopentadiene, bisstyrylanthracene, quinacridone, pyrrolopyridine, thiadiazolopyridine, cyclopentadiene , Styrylamine, fragrance Dimethylidin compounds, various metal complexes represented by 8-quinolinol metal complexes and rare earth complexes, polymer compounds such as polythiophene, polyphenylene, and polyphenylene vinylene, organic silanes, iridium trisphenylpyridine complexes, and transitions represented by platinum porphyrin complexes Examples of the light emitting material include a metal complex and a derivative thereof. As described above, it is preferable to substantially use a phosphorescent light emitting compound. Although the film thickness of a light emitting layer is not specifically limited, Usually, the thing of the range of 1 nm-5 micrometers is preferable, More preferably, it is 5 nm-1 micrometer, More preferably, it is 10 nm-500 nm.
The method for forming the light emitting layer is not particularly limited, and methods such as resistance heating vapor deposition, electron beam, sputtering, molecular lamination method, coating method, ink jet method, printing method, LB method, and transfer method are used. Of these, resistance heating vapor deposition and coating are preferred.

  The solvent used in the coating method of the light emitting layer forming method is preferably a solvent capable of dissolving or uniformly dispersing the host material and the light emitting material. The light emitting layer of the present invention is preferably in a state where the host material and the light emitting material are uniformly dispersed.

  There may be one or a plurality of light emitting layers, and each layer may emit light with different emission colors, for example, may emit white as a whole. Further, white light may be emitted from a single light emitting layer.

The material of the hole injection layer and the hole transport layer may be any one having a function of injecting holes from the anode, a function of transporting holes, or a function of blocking electrons injected from the cathode. Good. Specific examples include carbazole, triazole, oxazole, oxadiazole, imidazole, polyarylalkane, pyrazoline, pyrazolone, phenylenediamine, arylamine, amino-substituted chalcone, styrylanthracene, fluorenone, hydrazone, stilbene, silazane, aromatic group Tertiary amine compounds, styrylamine compounds, aromatic dimethylidin compounds, porphyrin compounds, polysilane compounds, poly (N-vinylcarbazole), aniline copolymers, thiophene oligomers, conductive polymer oligomers such as polythiophene, organic Examples include silane, carbon films, compounds of the present invention, and derivatives thereof. The film thicknesses of the hole injection layer and the hole transport layer are not particularly limited, but are usually preferably in the range of 1 nm to 5 μm, more preferably 5 nm to 1 μm, and still more preferably 10 nm to 500 nm. . The hole injection layer and the hole transport layer may have a single layer structure composed of one or more of the materials described above, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.
As a method for forming the hole injection layer and the hole transport layer, a vacuum deposition method, an LB method, a method in which the hole injection transport material is dissolved or dispersed in a solvent, a coating method, an ink jet method, a printing method, or a transfer method is used. It is done. In the case of the coating method, it can be dissolved or dispersed together with the resin component. Examples of the resin component include polyvinyl chloride, polycarbonate, polystyrene, polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, and poly (N -Vinyl carbazole), hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate, ABS resin, polyurethane, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, silicone resin, and the like.

The material for the electron injection layer and the electron transport layer may be any material having any one of a function of injecting electrons from the cathode, a function of transporting electrons, and a function of blocking holes injected from the anode. Specific examples thereof include triazole, oxazole, oxadiazole, imidazole, fluorenone, anthraquinodimethane, anthrone, diphenylquinone, thiopyran dioxide, carbodiimide, fluorenylidenemethane, distyryl in addition to the metal complex of the present invention. Various metal complexes such as pyrazine, naphthalene, perylene and other aromatic ring tetracarboxylic anhydrides, metal complexes of phthalocyanine, 8-quinolinol, metal phthalocyanine, metal complexes having benzoxazole and benzothiazole as ligands, organic silanes And derivatives thereof. Although the film thickness of an electron injection layer and an electron carrying layer is not specifically limited, The thing of the range of 1 nm-5 micrometers is preferable normally, More preferably, it is 5 nm-1 micrometer, More preferably, it is 10 nm-500 nm. The electron injection layer and the electron transport layer may have a single layer structure composed of one or more of the above-described materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.
As a method for forming the electron injection layer and the electron transport layer, a vacuum deposition method, an LB method, a method in which the electron injection / transport material is dissolved or dispersed in a solvent, a coating method, an ink jet method, a printing method, a transfer method, and the like are used. In the case of the coating method, it can be dissolved or dispersed together with the resin component. As the resin component, for example, those exemplified in the case of the hole injection transport layer can be applied.

As a material for the protective layer, any material may be used as long as it has a function of preventing substances that promote device deterioration such as moisture and oxygen from entering the device. Specific examples thereof include metals such as In, Sn, Pb, Au, Cu, Ag, Al, Ti, and Ni, MgO, SiO, SiO ₂ , Al ₂ O ₃ , GeO, NiO, CaO, BaO, and Fe ₂ O. ₃ , metal oxides such as Y ₂ O ₃ , TiO ₂ , metal fluorides such as MgF ₂ , LiF, AlF ₃ , CaF ₂ , nitrides such as SiN _x , SiO _x N _y , polyethylene, polypropylene, polymethyl methacrylate A monomer mixture comprising polyimide, polyurea, polytetrafluoroethylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, a copolymer of chlorotrifluoroethylene and dichlorodifluoroethylene, tetrafluoroethylene and at least one comonomer Copolymer obtained by copolymerization, fluorine-containing copolymer having a cyclic structure in the main chain Polymer, 1% by weight of the water absorbing water absorption material, water absorption of 0.1% or less of moisture-proof material, and the like.
There is no particular limitation on the method for forming the protective layer. For example, vacuum deposition, sputtering, reactive sputtering, MBE (molecular beam epitaxy), cluster ion beam, ion plating, plasma polymerization (high frequency excitation ions) Plating method), plasma CVD method, laser CVD method, thermal CVD method, gas source CVD method, coating method, printing method, and transfer method can be applied.

  Examples The present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to the following examples.

Comparative Example 1
Copper phthalocyanine was evaporated on the ITO substrate to a thickness of 10 nm, NPD was evaporated to a thickness of 50 nm, and CBP and Ir (ppy) ₃ (Tris-Ortho-Metalated Complex of Iridium (III) with 2-Phenylpyridine) 10: The film was evaporated at a ratio of 1 (mass ratio) of 36 nm, and Alq was evaporated thereon at 36 nm. A patterned mask (mask with a light emitting area of 4 mm x 5 mm) is placed on the organic thin film, and a cathode is deposited (LiF is deposited to a thickness of about 1 nm, and aluminum is deposited to a thickness of about 200 nm). The organic electroluminescent element of Comparative Example 1 was produced. Using a source measure unit model 2400 made by Toyo Technica, applying a DC constant voltage to the EL element to emit light, using a luminance meter BM-8 from Topcon and a spectrum analyzer PMA-11 from Hamamatsu Photonics. Measured. As a result, green light emission of λ _max = 514 nm was obtained.

Example 1
An organic electroluminescent element of Example 1 was produced in the same manner as in Comparative Example 1 except that the compound (1-28) of the present invention was used instead of Alq. When the device was evaluated in the same manner as in Comparative Example 1, green light emission of λmax = 514 nm was obtained, and the luminance when 12 V was applied was 1.8 times that of Comparative Example 1.

Example 2
An organic electroluminescent element of Example 2 was prepared in the same manner as Comparative Example 1 except that the compound (1-24) of the present invention was used instead of Alq. When the device was evaluated in the same manner as in Comparative Example 1, green light emission of λmax = 515 nm was obtained, and the luminance when 12 V was applied was 8.5 times that of Comparative Example 1.

Example 3
An organic electroluminescent element of Example 3 was prepared in the same manner as in Comparative Example 1 except that the compound (1-58) of the present invention was used instead of Alq. When the device was evaluated in the same manner as in Comparative Example 1, green light emission of λmax = 514 nm was obtained, and the luminance when 12 V was applied was 3.0 times that of Comparative Example 1.

Example 4
An organic electroluminescent element of Example 4 was produced in the same manner as in Comparative Example 1 except that the compound (1-66) of the present invention was used instead of Alq. When the device was evaluated in the same manner as in Comparative Example 1, green light emission of λmax = 514 nm was obtained, and the luminance when 12 V was applied was 7.7 times that of Comparative Example 1.

Example 5
Organic electroluminescence of Example 5 in the same manner as in Comparative Example 1 except that the compound (1-24) of the present invention was used instead of Alq and the compound (1-65) of the present invention was used instead of CBP. A device was created. When the device was evaluated in the same manner as in Comparative Example 1, green light emission of λmax = 516 nm was obtained, and the luminance when 12 V was applied was 11 times that of Comparative Example 1.

Example 6
When the number of dark spots after the organic electroluminescent elements of Comparative Example 1 and Examples 1 to 5 were driven for 10 hours was compared, the elements of Examples 1 to 5 generated dark spots compared to Comparative Example 1. The number was small.

Comparative Example 2
Copper phthalocyanine is deposited on the ITO substrate by 10 nm, NPD is deposited by 50 nm thereon, CBP and Ir (ppy) ₃ are deposited by 36 nm at a ratio (mass ratio) of 10: 1, and BAlq is deposited thereon. 10nm was vapor-deposited, and also Alq was vapor-deposited 26nm on this. A patterned mask (mask with a light emitting area of 4 mm x 5 mm) is placed on the organic thin film, and a cathode is deposited (LiF is deposited to a thickness of about 1 nm, and aluminum is deposited to a thickness of about 200 nm). The organic electroluminescent element of Comparative Example 1 was produced. Using a source measure unit model 2400 made by Toyo Technica, applying a DC constant voltage to the EL element to emit light, using a luminance meter BM-8 from Topcon and a spectrum analyzer PMA-11 from Hamamatsu Photonics. Measured. As a result, green light emission of λ _max = 514 nm was obtained.

Example 7
An organic electroluminescent element of Example 7 was produced in the same manner as in Comparative Example 2 except that the compound (1-67) of the present invention was used instead of BAlq. When the element of Example 6 was evaluated in the same manner as in Comparative Example 2, green light emission of λ _max = 514 nm was obtained, and the luminance when 12 V was applied was 4.5 times that of Comparative Example 2.

Example 8
An organic electroluminescent element of Example 8 was produced in the same manner as in Comparative Example 2 except that the compound (1-56) of the present invention was used instead of BAlq. When the element of Example 6 was evaluated in the same manner as in Comparative Example 2, green light emission of λ _max = 515 nm was obtained, and the luminance when 12 V was applied was 4.6 times that of Comparative Example 2.

Example 9
An organic electroluminescent element of Example 9 was produced in the same manner as in Comparative Example 2 except that the compound (1-70) of the present invention was used instead of Alq. When the element of Example 6 was evaluated in the same manner as in Comparative Example 2, green light emission of λ _max = 515 nm was obtained, and the luminance when 12 V was applied was 1.7 times that of Comparative Example 2.

Example 10
The organic electric field of Example 10 was the same as Comparative Example 2 except that the compound (1-67) of the present invention was used instead of BAlq and the compound (1-74) of the present invention was used instead of Alq. A light emitting device was prepared. When the element of Example 6 was evaluated in the same manner as in Comparative Example 2, green light emission of λ _max = 515 nm was obtained, and the luminance when 12 V was applied was 10.6 times that of Comparative Example 2.

Example 11
When the number of dark spots generated after the devices of Comparative Example 2 and Examples 7 to 10 were driven for 10 hours was compared, the device of Examples 7 to 10 was compared with the device of Comparative Example 2. There were few occurrences.

Claims (9)

  An organic electroluminescence device having a light emitting layer and at least one organic layer between an anode and a cathode, wherein at least one kind of the fifth to sixth periods and the fifth group is disposed between the light emitting layer and the cathode. An organic electroluminescence device having at least one organic layer containing a metal complex of Group 11 to Group 11 or a rare earth metal complex.   The central metal of the metal complex is selected from the group consisting of iron, manganese, nickel, copper, molybdenum, ruthenium, rhodium, palladium, silver, indium, tin, antimony, rare earth metal, tungsten, rhenium, osmium, iridium, platinum, and gold. The organic electroluminescent element according to claim 1, which is selected.   The organic electroluminescent element according to claim 1, wherein the metal complex is an organometallic complex. The metal complex is represented by the following general formula (1), the following general formula (2), the following general formula (3), the following general formula (4), the following general formula (5), or the following general formula (6). The organic electroluminescent element according to claim 1, wherein the organic electroluminescent element is a compound.

In the formula, Q ¹¹ , Q ²¹ , Q ⁴¹ and Q ⁶¹ each represent a group forming a nitrogen-containing heterocycle, and Z ¹¹ , Z ²¹ , Z ³¹ , Z ⁴¹ , Z ⁵¹ and Z ⁶¹ each represent a linking group. , M ¹¹ , M ²¹ , M ³¹ , M ⁴¹ , M ⁵¹ , and M ⁶¹ each represent a metal ion or a rare earth metal ion in Groups 5 to 11 and 5 to 6 in the periodic table, ¹¹ , L ²¹ , L ³¹ , L ⁴¹ , L ⁵¹ , L ⁶¹ each represents a ligand, R ²¹ , R ³² , R ⁵² each represents a hydrogen atom or a substituent, and X ⁴¹ , X ⁵¹ , X ⁶¹ Each represents a substituted carbon atom or a substituted nitrogen atom. n ¹¹ , n ²¹ , n ³¹ , n ⁴¹ , n ⁵¹ , and n ⁶¹ each represent an integer of 0 to 2, and m ¹¹ , m ²¹ , m ³¹ , m ⁴¹ , m ⁵¹ , and m ⁶¹ each represent 1 to 4 An integer is represented, and m ¹² , m ²² , m ³² , m ⁴² , m ⁵² , and m ⁶² each represent an integer of 0 to 6.   The organic electroluminescent element as described in any one of Claims 1-4 with which the organic layer containing the said metal complex is adjacent to the light emitting layer.   The organic electroluminescent element according to claim 1, further comprising an electron transport layer between the organic layer containing the metal complex and the cathode.   The organic electroluminescent element according to claim 1, wherein the light emitting material in the light emitting layer is at least one phosphorescent light emitting compound. The T ₁ value of the metal complex is 60 kcal / mol (251 kJ / mol) or more, and λmax (the maximum emission wavelength) of phosphorescence obtained from the phosphorescent compound is shorter than 550 nm. Organic electroluminescent element.   The organic electroluminescent element according to claim 7 or 8, wherein the light emitting layer does not contain a fluorescent light emitting compound, and at least one phosphorescent light emitting compound substantially emits light.