JP6028668B2 - Transparent electrodes, electronic devices and organic electroluminescence devices - Google Patents

Description

The present invention relates to a transparent electrode, an electronic device and an organic electroluminescence device, and particularly to a transparent electrode having both conductivity and light transmission and excellent durability, and an electronic device and an organic electroluminescence device using the transparent electrode. ..

An organic EL element (also referred to as an organic electroluminescent element) using an organic material electroluminescence (hereinafter referred to as EL) is a thin film type capable of emitting light at a low voltage of about several V to several tens of V. It is a completely solid element and has many excellent features such as high brightness, high emission efficiency, thinness, and light weight. For this reason, it has been attracting attention in recent years as a backlight for various displays, a display board for signboards and emergency lights, and a surface emitter such as an illumination light source.

Such an organic EL element has a configuration in which a light emitting layer made of an organic material is arranged between two electrodes, and the light emitted from the light emitting layer passes through the electrodes and is taken out to the outside. Therefore, at least one of the two electrodes is configured as a transparent electrode.

As the transparent electrode, _{an oxide semiconductor-based material such as indium tin oxide (SnO 2-In 2} O ₃ : Indium Tin Oxide: ITO) is generally used, but it is low by laminating ITO and silver. Studies aimed at resistance have also been made (see, for example, Patent Documents 1 and 2). However, since ITO uses indium, which is a rare metal, the material cost is high, and in order to reduce the resistance, it is necessary to perform annealing treatment at about 300 ° C. after film formation.

Therefore, a technique for achieving both transmittance and conductivity by forming a thin film using an alloy of silver (Ag) and magnesium (Mg) having high electric conductivity (see, for example, Patent Document 3), and A technique for forming a thin film using inexpensive and easily available zinc (Zn) or tin (Sn) as a raw material (see, for example, Patent Document 4), and a short wavelength region by forming a thin film using an alloy of silver and aluminum. (For example, see Patent Document 5) and the like have been proposed.
However, the resistance value of the electrode disclosed in Patent Document 3 is at most about 100Ω / □, which is insufficient for the conductivity of the electrode. In addition, magnesium is easily oxidized, so that there is a problem that deterioration with time is remarkable. there were.
The electrode disclosed in Patent Document 4 has a problem that a sufficient resistance value cannot be obtained. Further, the Zn-containing ZnO-based thin film reacts with water and its performance tends to fluctuate, and the Sn-containing SnO _2- based thin film has a problem that etching is difficult.
The resistance value of the electrode disclosed in Patent Document 5 immediately after fabrication is 128 Ω / □ at most, and it cannot be said that the electrode is a transparent electrode having sufficient conductivity and light transmission.

On the other hand, an organic EL device in which silver is deposited with a film thickness of 15 nm as a cathode is disclosed (see, for example, Patent Document 6).
However, in the silver film disclosed in Patent Document 6, it is difficult to maintain the electrode characteristics because silver easily migrates when the film is thinned, and the development of a new technique is desired.

JP-A-2002-015623 Japanese Unexamined Patent Publication No. 2006-164961 Japanese Unexamined Patent Publication No. 2006-344497 Japanese Unexamined Patent Publication No. 2007-031786 Japanese Unexamined Patent Publication No. 2009-151963 U.S. Patent Application Publication 2011/0260148

The present invention has been made in view of the above problems and situations, and the problem to be solved thereof is a transparent electrode having sufficient conductivity and light transmittance and excellent durability, an electronic device provided with the transparent electrode, and the like. It is to provide an organic electroluminescence element.

As a result of investigating the causes of the above problems in order to solve the above problems, the present inventor is a transparent electrode including a conductive layer and an intermediate layer provided adjacent to the conductive layer, and is conductive. Excellent conductivity because the layer contains silver as a main component and the intermediate layer contains an aromatic heterocyclic compound having two or more aromatic heterocyclic groups having three or more heteroatoms in the molecule. We have found that it is possible to achieve both light transmittance and excellent durability, and have arrived at the present invention.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. 1. An intermediate layer, a transparent electrode and a deposited electrically conductive layer adjacent to on the intermediate layer,
The conductive layer contains silver as a main component and contains silver as a main component.
The intermediate layer is a transparent electrode containing an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms.

〔一般式（１）において、Ｅ_１〜Ｅ_６は炭素原子又は窒素原子を表し、このうち少なくとも二つは炭素原子を表す。Ｒ_１は置換基を表す。ｍ１は０〜４の整数を表す。ｍ１が２以上の場合、Ｒ_１は同じ置換基であっても異なる置換基であってもよい。Ｄ_１はヘテロ原子を３個以上有する芳香族複素環基を表す。ｎ１は２〜６の整数を表す。複数のＤ_１は、同じであっても異なっていてもよい。〕 2. 2. The transparent electrode according to Item 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (1).

[In the general formula (1), E _{1 to} E ₆ represent carbon atoms or nitrogen atoms, and at least two of them represent carbon atoms. R ₁ represents a substituent. m1 represents an integer from 0 to 4. If m1 is 2 or more, R ₁ may be a different substituents be the same substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents an integer of 2 to 6. The plurality of D _1s may be the same or different. ]

〔一般式（２）において、ＸはＮＲ_１２、酸素原子又は硫黄原子を表す。Ｒ_１２は水素原子若しくは置換基を表す。Ｅ_１１〜Ｅ_１８は炭素原子又は窒素原子を表し、このうち少なくとも二つは炭素原子を表す。ｍ１１は０〜６の整数を表す。Ｒ_１１は置換基を表す。ｍ１１が２以上の場合、Ｒ_１１は同じであっても異なっていてもよい。Ｄ_１１はヘテロ原子を３個以上有する芳香族複素環基を表す。ｎ１１は２〜８の整数を表す。複数のＤ_１１は、同じであっても異なっていてもよい。〕 3. 3. The transparent electrode according to Item 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (2).

[In the general formula (2), X represents NR ₁₂ , an oxygen atom or a sulfur atom. R ₁₂ represents a hydrogen atom or a substituent. E _{11 to} E ₁₈ represent carbon atoms or nitrogen atoms, of which at least two represent carbon atoms. m11 represents an integer from 0 to 6. R ₁₁ represents a substituent. If m11 is 2 or more, R ₁₁ may be different even in the same. D ₁₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n11 represents an integer of 2-8. The plurality of D _11s may be the same or different. ]

〔一般式（３）において、Ｅ_２１〜Ｅ_３０は炭素原子又は窒素原子を表し、このうち少なくとも二つは炭素原子を表す。Ｒ_２１は置換基を表す。ｍ２１は０〜８の整数を表す。ｍ１１が２以上の場合、Ｒ_２１は、同じであっても異なってもよい。Ｄ_２１はヘテロ原子を３個以上有する芳香族複素環基を表す。ｎ２１は２〜１０の整数を表す。複数のＤ_１１は、同じであっても異なっていてもよい。〕 4. The transparent electrode according to Item 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (3).

[In the general formula (3), E _{21 to} E ₃₀ represent a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. R ₂₁ represents a substituent. m21 represents an integer from 0 to 8. If m11 is 2 or _{more, R 21} may be the same or different. D ₂₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n21 represents an integer of 2 to 10. The plurality of D _11s may be the same or different. ]

5. The transparent electrode according to the first to fourth paragraphs, wherein the hetero atom is a nitrogen atom, an oxygen atom or a sulfur atom.

6. The transparent electrode according to the first to fifth terms, wherein the aromatic heterocyclic group is a five-membered ring.

7. An electronic device comprising the transparent electrode according to any one of items 1 to 6.

8. An organic electroluminescence device comprising the transparent electrode according to any one of items 1 to 6.

According to the present invention, it is possible to provide a transparent electrode having sufficient conductivity and light transmittance and excellent durability, an electronic device provided with the transparent electrode, and an organic electroluminescence device.

Although the mechanism of expression and the mechanism of action of the effects of the present invention have not been clarified, it is presumed as follows.

That is, the transparent electrode of the present invention is provided with a conductive layer composed mainly of silver on the upper part of the intermediate layer, and the intermediate layer is an aromatic heterocyclic group having three or more heteroatoms. The composition is such that an aromatic heterocyclic compound having two or more of the above is contained in the molecule.
As a result, when a conductive layer is formed on the upper part of the intermediate layer, two aromatic heterocyclic groups having three or more heteroatoms containing silver atoms constituting the conductive layer in the intermediate layer are contained in the molecule. By interacting with an aromatic heterocyclic compound having more than one, the diffusion distance of silver atoms on the surface of the intermediate layer was reduced, and the aggregation of silver at specific points could be suppressed.
That is, the silver atom first forms a two-dimensional nucleus on the surface of the intermediate layer containing the silver-affinity compound having a component having an affinity for the silver atom, and forms a two-dimensional single crystal layer around it. The film is formed by the layered growth type (Frank-van der Merwe: FM type) film growth.

In general, an island-like growth type (Volumer-) in which silver atoms attached on the surface of the intermediate layer are bonded while diffusing on the surface to form a three-dimensional nucleus and grow in a three-dimensional island shape. It is considered that an island-shaped film is easily formed by the film growth in Weber: VW type).
However, in the present invention, the island-like growth is caused by the aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms, which are silver-affinitive compounds contained in the intermediate layer. Is suppressed and stratified growth is promoted.
Therefore, a conductive layer having a thin layer thickness but a uniform layer thickness can be obtained. As a result, it is possible to obtain a transparent electrode in which conductivity is ensured while maintaining light transmittance with a thinner layer thickness.
The present invention is also a proposal of a new compound capable of suppressing the aggregation of silver.

Schematic cross-sectional view showing an example of the configuration of the transparent electrode of the present invention. Schematic cross-sectional view showing a first example of an organic EL device using the transparent electrode of the present invention. Schematic cross-sectional view showing a second example of an organic EL device using the transparent electrode of the present invention. Schematic cross-sectional view showing a third example of an organic EL device using the transparent electrode of the present invention. Schematic cross-sectional view of an illuminating device having a large light emitting surface using an organic EL element provided with the transparent electrode of the present invention. Schematic cross-sectional view of a light emitting panel provided with the organic EL element produced in the examples.

The transparent electrode of the present invention, an intermediate layer, a transparent electrode and a deposited electrically conductive layer adjacent to on the intermediate layer,
The conductive layer contains silver as a main component and contains silver as a main component.
The intermediate layer is characterized by containing an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms. This feature is a technical feature common to the inventions according to claims 1 to 8.

In an embodiment of the present invention, the aromatic heterocyclic compound is preferably a compound having a structure represented by the general formula (1) in terms of affinity with silver and stability.

Further, in the present invention, the aromatic heterocyclic compound is preferably a compound having a structure represented by the general formula (2) in terms of affinity with silver and stability.

Further, in the present invention, the aromatic heterocyclic compound is preferably a compound having a structure represented by the general formula (3) in terms of affinity with silver and stability.

Further, in the present invention, it is preferable that the hetero atom is a nitrogen atom, an oxygen atom or a sulfur atom from the viewpoint of exhibiting the effect of the present invention.

Further, in the present invention, it is preferable that the aromatic heterocyclic group is a five-membered ring from the viewpoint of exhibiting the effect of the present invention.

The transparent electrode of the present invention can be suitably provided in an electronic device. As a result, it is possible to obtain an electronic device having sufficient conductivity and light transmission and having excellent durability.

The transparent electrode of the present invention can be suitably provided in an organic electroluminescence device. As a result, it is possible to obtain an organic electroluminescence element having sufficient conductivity and light transmittance and excellent durability.

Hereinafter, the present invention, its constituent elements, and modes and modes for carrying out the present invention will be described in detail.
In addition, "~" shown in this invention is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value.

≪1. Transparent electrode ≫
<Structure of transparent electrode>
FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the transparent electrode of the present invention.
As shown in FIG. 1, the transparent electrode 1 has a two-layer structure in which an intermediate layer 1a and a conductive layer 1b are laminated on the intermediate layer 1a. For example, the intermediate layer 1a is formed on the upper part of the substrate 11. , The conductive layer 1b is provided in this order. Of these, the intermediate layer 1a is a layer containing an aromatic heterocyclic compound, and the conductive layer 1b is a layer containing silver as a main component.
In the present invention, the main component of the conductive layer 1b means the component having the highest composition ratio among the components constituting the conductive layer. The conductive layer 1b of the present invention contains silver as a main component, and the composition ratio thereof is preferably 60% by mass or more, more preferably 90% by mass or more, and preferably 98% by mass or more. Especially preferable.
Further, the transparency of the transparent electrode 1 of the present invention means that the light transmittance at a wavelength of 550 nm is 50% or more.

Next, a detailed configuration will be described in the order of the substrate 11 on which the transparent electrode 1 having such a laminated structure is provided, the intermediate layer 1a constituting the transparent electrode 1, and the conductive layer 1b.

[substrate]
Examples of the substrate 11 on which the transparent electrode 1 of the present invention is formed include, but are not limited to, glass, plastic, and the like. Further, the substrate 11 may be transparent or opaque. When the transparent electrode 1 of the present invention is used for an electronic device that extracts light from the substrate 11 side, the substrate 11 is preferably transparent. Examples of the transparent substrate 11 preferably used include glass, quartz, and a transparent resin film.

Examples of the glass include silica glass, soda lime silica glass, lead glass, borosilicate glass, non-alkali glass and the like. From the viewpoint of adhesion to the intermediate layer 1a, durability, and smoothness, the surface of these glass materials may be subjected to physical treatment such as polishing, if necessary, from inorganic substances or organic substances. Or a hybrid coating obtained by combining these coatings may be formed.

Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, and cellulose acetate propionate. CAP), cellulose acetate phthalate, cellulose esters such as cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyether sulfone (PES), polyphenylene sulfide, polysulfones, polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylates, Arton (trade name: JSR) or Appel Cycloolefin resins such as (trade name: manufactured by Mitsui Chemicals, Inc.) can be mentioned.

As described above, a film made of an inorganic substance or an organic substance or a hybrid film combining these films may be formed on the surface of the resin film. Such coating films and hybrid coating films have a water vapor permeability (25 ± 0.5 ° C., relative humidity 90 ± 2% RH) of 0.01 g / m ² and measured by a method in accordance with JIS K 7129-1992. A barrier film (also referred to as a barrier film or the like) of 24 hours or less is preferable. Further, JIS K 7126-1987 oxygen permeability measured in compliance with the method provided in the ^{1 × 10 -3 ml / m 2} · 24h · atm or less, the water vapor permeability of ^{1 × 10 -5 g / m 2} · 24h The following high barrier film is preferable.

The material for forming the barrier film as described above may be any material having a function of suppressing the infiltration of factors that cause deterioration of electronic devices and organic EL elements such as moisture and oxygen, and for example, silicon oxide and dioxide. Silicon, silicon nitride and the like can be used. Further, in order to improve the brittleness of the barrier film, it is more preferable to have a laminated structure of these inorganic layers and a layer made of an organic material (organic layer). The stacking order of the inorganic layer and the organic layer is not particularly limited, but it is preferable to stack the inorganic layer and the organic layer alternately a plurality of times.

The method for producing the barrier film is not particularly limited, and for example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight. Although legal, plasma CVD method, laser CVD method, thermal CVD method, coating method and the like can be used, the atmospheric pressure plasma polymerization method described in JP-A-2004-68143 is particularly preferable.

On the other hand, when the substrate 11 is made of an opaque material, for example, a metal substrate such as aluminum or stainless steel, a film or opaque resin substrate, a ceramic substrate, or the like can be used.

[Middle layer]
The intermediate layer 1a according to the present invention is a layer formed by using an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule containing three or more heteroatoms.
When such an intermediate layer 1a is formed on the substrate 11, the film forming method includes a method using a wet process such as a coating method, an inkjet method, a coating method, and a dip method, or a vapor deposition method ( Resistance heating, EB method, etc.), sputtering method, CVD method, and other methods using a dry process can be mentioned. Of these, the thin-film deposition method is preferably applied.

Next, the aromatic heterocyclic compounds represented by the general formulas (1) to (3) will be described in detail.

The aromatic heterocyclic compound is preferably a compound having a structure represented by the following general formula (1).

In the general formula (1), E _{1 to} E ₆ represent a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. R ₁ represents a substituent. m1 represents an integer from 0 to 4. If m1 is 2 or more, R ₁ may be a different substituents be the same substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents an integer of 2 to 6. The plurality of D _1s may be the same or different.

In the general formula (1), the _{substituent represented by R 1} is an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl). Group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, propargyl group, etc.) Etc.), aromatic hydrocarbon groups (also referred to as aromatic carbocyclic groups, aryl groups, etc., for example, phenyl group, p-chlorophenyl group, mesityl group, trill group, xsilyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl Group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, frill group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group) , Pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating one of any carbon atoms constituting the carbolin ring of the carbolinyl group replaced with a nitrogen atom), phthalazinyl. Groups, etc.), heterocyclic groups (eg, pyrrolidyl group, imidazolidyl group, morpholic group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group). , Dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio) Group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, phenylthio group, naphthylthio group, etc.) , Methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (sulfamoyl group, etc.) For example, aminosulfonyl group, methylaminosul Honyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.) , Acyl group (eg, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group Etc.), acyloxy group (eg, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (eg, methylcarbonylamino group, ethyl) Carbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group Etc.), carbamoyl group (eg aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecyl Aminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methyl ureido group, ethyl ureido group, pentyl ureido group, cyclohexyl ureido group, octyl ureido group, dodecyl ureido group) , A phenylureid group, a naphthylureid group, a 2-pyridylaminoureid group, etc.), a sulfinyl group (for example, a methylsulfinyl group, an ethylsulfinyl group, a butylsulfinyl group, a cyclohexylsulfinyl group, a 2-ethylhexylsulfinyl group, a dodecylsulfinyl group, a phenylsulfinyl group. , Naftylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group) , Cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (eg, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, amino) Group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, piperidyl group (also called piperidinyl group), 2 , 2,6,6-tetramethylpiperidinyl group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, penta) Fluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphoric acid Examples thereof include an ester group (for example, a dihexylphosphoryl group, etc.), a phosphite ester group (for example, a diphenylphosphinyl group, etc.), a phosphono group, and the like.

In the general formula (1), _{examples of the ring formed by E 1 to} E ₆ include benzene, naphthalene, pyridine, pyridazine, pyrimidine, pyrazine, 1,3,5-triazine, quinoxaline, quinazoline, quinoline and the like.
In the general formula (1), the aromatic heterocyclic group represented by _{D 1 is preferably as follows.}

R ₃₁ , R ₃₂ , R ₃₃ and R ₃₄ represent a hydrogen atom or a substituent. As the substituent, the same group as R ₁ is represented. L represents a bond or a divalent linking group. Linking group as for example an alkylene group, a cycloalkylene group, an arylene group, a group containing a hetero atom (e.g., -O -, - 2 divalent group containing a chalcogen atom S- like, -N (R 35) _- group, wherein R ₃₅ represents a hydrogen atom or an alkyl group), an amide group, a carbamoyl group and the like. Note that * represents a binding site.

It is also preferable that the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (2).

In the general formula (2), X represents NR ₁₂ , an oxygen atom or a sulfur atom. R ₁₂ represents a hydrogen atom or a substituent. E _{11 to} E ₁₈ represent carbon atoms or nitrogen atoms, of which at least two represent carbon atoms. m11 represents an integer from 0 to 6. R ₁₁ represents a substituent. If m11 is 2 or more, R ₁₁ may be different even in the same. D ₁₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n11 represents an integer of 2-8. The plurality of D _11s may be the same or different.

In the general formula (2), examples of the _{aromatic heterocyclic group represented by D 11} include the same groups as D _1.

In the general formula (2), examples of the substituent represented _{by R 11} include the same substituents represented by R _1.
In the general formula (2), the _{rings formed by E 11 to} E ₁₈ are preferably as follows.

It is also preferable that the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (3).

In the general formula (3), E _{21 to} E ₃₀ represent a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. R ₂₁ represents a substituent. m21 represents an integer from 0 to 8. If m11 is 2 or _{more, R 21} may be the same or different. D ₂₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n21 represents an integer of 2 to 10. The plurality of D _11s may be the same or different.

In the general formula (3), examples of the substituent represented by _{R 21} include those similar to those represented by _{R 1.}
In the general formula (3), _{examples of the ring formed by E 21 to} E ₃₀ include 1,1'-biphenyl, 2-phenylpyridine, 3-phenylpyridine, 4-phenylpyridine, 2,2'-bipyridine, and 3 , 3'-bipyridine, 4,4'-bipyridine and the like.
In the general formula (3), examples of the _{aromatic heterocyclic group represented by D 21} include the same groups as D _1.

_{The substituents (D 11} and R ₁₁ ) included in the general formula (2) may include either a ring formed by _{E 11} to ₁₄ or a ring formed by E _{15 to} E _18. It represents that. That is, for example, _{only the ring formed by E 11} to ₁₄ may have a plurality of substituents, or either the ring formed by _{E 11} to ₁₄ or the ring formed by E _{15 to} E _{18 may be present.} It can also have a substituent. The same applies to the general formula (3).

[Specific examples of compounds contained in the intermediate layer]
The hetero atom contained in the aromatic heterocyclic compound is preferably a nitrogen atom, an oxygen atom or a sulfur atom. The aromatic heterocyclic group is preferably a five-membered ring.
Specific examples of the aromatic heterocyclic compound contained in the intermediate layer 1a of the present invention are shown below, but the present invention is not limited thereto.

The organic compound according to the present invention can be easily synthesized according to a conventionally known synthesis method.

Synthesis Example 1 (Synthesis of I-7)
3.14 g of 1,3,5-tribromobenzene, 4.20 g of benzotriazole, 1.43 g of cuprous oxide, 1.30 g of dipivaloylmethane, 6.36 g of potassium phosphate, 50 ml of dimethyl sulfoxide (DMSO). The mixture was heated and stirred at 160 ° C. under a nitrogen stream for 24 hours. The reaction mixture was filtered to remove insoluble matter, THF was added, and the mixture was washed with saturated brine. The solvent was removed by vacuum distillation, and the obtained crude crystals were purified by column chromatography (SiO ₂ , developing solution THF / toluene) to obtain 2.27 g (yield 53.0%, pale yellow crystals) of the target product. It was.

Synthesis Example 2 (Synthesis of I-29)
4.36 g of diiododibenzothiophene, 4.45 g of mercaptophenyltetrazole, 1.10 g of cuprous oxide, 1.00 g of dipivaloyl methane, 4.36 g of potassium phosphate, and 50 ml of DMSO at 160 ° C. for 24 hours under a nitrogen stream. It was heated and stirred. The reaction mixture was filtered to remove insoluble matter, THF was added, and the mixture was washed with saturated brine. The solvent was removed by vacuum distillation, and the obtained crude crystals were purified by column chromatography (SiO ₂ , developing solution THF / toluene) to obtain 3.00 g (yield 56.0%, pale yellow crystals) of the target product. It was.

Synthesis Example 3 (Synthesis of I-41)
4,4'-diiodo-1,1'-biphenyl 4.06 g, mercaptophenyloxadiazole 3.80 g, cuprous oxide 1.10 g, dipivaloyl methane 1.00 g, potassium phosphate 4.36 g, 50 ml of DMSO was heated and stirred at 160 ° C. under a nitrogen stream for 24 hours. The reaction mixture was filtered to remove insoluble matter, THF was added, and the mixture was washed with saturated brine. The solvent was removed by vacuum distillation, and the obtained crude crystals were purified by column chromatography (SiO ₂ , developing solution THF / toluene) to obtain 2.43 g (yield 48.0%, pale yellow crystals) of the target product. It was.

[Conductive layer]
The conductive layer 1b is a layer composed of silver as a main component, and is a layer formed on the intermediate layer 1a.
Examples of the film forming method of the conductive layer 1b include a method using a wet process such as a coating method, an inkjet method, a coating method, and a dip method, a vapor deposition method (resistive heating, EB method, etc.), a sputtering method, and a CVD method. And the like using a dry process such as. Of these, the thin-film deposition method is preferably applied.
Further, since the conductive layer 1b is formed on the intermediate layer 1a, it is sufficiently conductive even if there is no high temperature annealing treatment (for example, a heating process of 150 ° C. or higher) after the film formation of the conductive layer 1b. However, if necessary, a high-temperature annealing treatment or the like may be performed after the film formation.

The conductive layer 1b may be composed of an alloy containing silver (Ag), and examples of such an alloy include silver magnesium (AgMg), silver copper (AgCu), silver palladium (AgPd), and silver palladium. Examples thereof include copper (AgPdCu) and silver indium (AgIn).

The conductive layer 1b as described above may have a structure in which a layer composed of silver as a main component is divided into a plurality of layers and laminated as needed.

Further, the conductive layer 1b preferably has a layer thickness in the range of 5 to 20 nm, and more preferably in the range of 5 to 12 nm.
When the layer thickness is thinner than 20 nm, the absorption component or the reflection component of the layer is reduced, and the transmittance of the transparent electrode is improved, which is more preferable. Further, it is preferable that the layer thickness is thicker than 5 nm because the conductivity of the layer becomes sufficient.

In the transparent electrode 1 having a laminated structure composed of the intermediate layer 1a and the conductive layer 1b formed on the intermediate layer 1a as described above, the upper part of the conductive layer 1b may be covered with a protective film. Another conductive layer may be laminated. In this case, it is preferable that the protective film and another conductive layer have light transmission so as not to impair the light transmission of the transparent electrode 1. Further, a layer may be provided in the lower part of the intermediate layer 1a, that is, between the intermediate layer 1a and the substrate 11, if necessary.

<Effect of transparent electrode>
The transparent electrode 1 having the above configuration contains silver as a main component on an intermediate layer 1a containing an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms. The conductive layer 1b containing the mixture is provided. As a result, when the conductive layer 1b is formed on the upper part of the intermediate layer 1a, the silver atoms constituting the conductive layer 1b interact with the organic compound contained in the intermediate layer 1a, and the intermediate layer of the silver atoms is formed. The diffusion distance on the surface of 1a is reduced, and silver aggregation is suppressed.

Here, in general, in the film formation of the conductive layer containing silver as a main component, the thin film grows in an island-like growth type (Volumer-Weber: VW type), so that the silver particles are easily isolated in an island shape. When the layer thickness (thickness) is thin, it is difficult to obtain conductivity, and the sheet resistance value becomes high.
Therefore, it is necessary to increase the film thickness in order to secure the conductivity, but if the film thickness is increased, the light transmittance decreases, so that it is not suitable as a transparent electrode.

However, according to the transparent electrode 1 of the present invention, since silver aggregation is suppressed on the intermediate layer 1a as described above, layered growth occurs in the film formation of the conductive layer 1b composed of silver as a main component. A thin film grows in a mold (Frank-van der Merwe: FM type).

Further, here, the transparency of the transparent electrode 1 of the present invention means that the light transmittance at a wavelength of 550 nm is 50% or more, but each of the above-mentioned materials used as the intermediate layer 1a contains silver as a main component. A film having sufficiently good light transmittance is formed as compared with the conductive layer 1b. On the other hand, the conductivity of the transparent electrode 1 is mainly ensured by the conductive layer 1b. Therefore, as described above, the conductive layer 1b composed of silver as a main component has a thinner layer thickness to ensure conductivity, thereby improving the conductivity of the transparent electrode 1 and transmitting light. It is possible to achieve both improvement and improvement.

≪2. Applications of transparent electrodes ≫
The transparent electrode 1 having the above-described configuration can be used in various electronic devices. Examples of electronic devices include organic EL elements, LEDs (Light Emitting Diodes), liquid crystal elements, solar cells, touch panels, and the like, and the above-mentioned transparent electrode members are examples of electrode members that require light transmission in these electronic devices. The electrode 1 can be used.
Hereinafter, as an example of the application, an embodiment of an organic EL device using the transparent electrode 1 of the present invention will be described.

≪3. First example of organic EL element ≫
<Structure of organic EL element>
FIG. 2 is a schematic cross-sectional view showing a first example of an organic EL device using the above-mentioned transparent electrode 1 as an example of the electronic device of the present invention.
The configuration of the organic EL element will be described below based on this figure.

As shown in FIG. 2, the organic EL element 100 is provided on the transparent substrate (substrate) 13, and the transparent electrode 1 and the light emitting functional layer 3 formed of an organic material are used in this order from the transparent substrate 13 side. And the counter electrode 5a are laminated in this order. In the organic EL element 100, the transparent electrode 1 of the present invention described above is used as the transparent electrode 1. Therefore, the organic EL element 100 is configured to take out the generated light (hereinafter referred to as emission light h) from at least the transparent substrate 13 side.

Further, the layer structure of the organic EL element 100 is not limited to the examples described below, and may be a general layer structure. Here, the transparent electrode 1 functions as an anode (that is, an anode), and the counter electrode 5a functions as a cathode (that is, a cathode). In this case, for example, the light emitting functional layer 3 has a structure in which the hole injection layer 3a / hole transport layer 3b / light emitting layer 3c / electron transport layer 3d / electron injection layer 3e are laminated in this order from the transparent electrode 1 side which is the anode. Although exemplified, it is essential to have at least a light emitting layer 3c constructed by using an organic material. The hole injection layer 3a and the hole transport layer 3b may be provided as the hole transport injection layer. The electron transport layer 3d and the electron injection layer 3e may be provided as an electron transport injection layer. Further, among these light emitting functional layers 3, for example, the electron injection layer 3e may be made of an inorganic material.

Further, in the light emitting functional layer 3, in addition to these layers, a hole blocking layer, an electron blocking layer and the like may be laminated at necessary positions as needed. Further, the light emitting layer 3c may have each color light emitting layer that generates light emitted in each wavelength region, and each of these color light emitting layers may be laminated via a non-light emitting auxiliary layer. The auxiliary layer may function as a hole blocking layer and an electron blocking layer. Further, the counter electrode 5a, which is a cathode, may also have a laminated structure, if necessary. In such a configuration, only the portion where the light emitting functional layer 3 is sandwiched between the transparent electrode 1 and the counter electrode 5a is the light emitting region in the organic EL element 100.

Further, in the layer structure as described above, the auxiliary electrode 15 may be provided in contact with the conductive layer 1b of the transparent electrode 1 for the purpose of reducing the resistance of the transparent electrode 1.

The organic EL element 100 having the above configuration is sealed on the transparent substrate 13 with a sealing material 17 described later for the purpose of preventing deterioration of the light emitting functional layer 3 constructed by using an organic material or the like. ing. The sealing material 17 is fixed to the transparent substrate 13 side via an adhesive 19. However, it is assumed that the terminal portions of the transparent electrode 1 and the counter electrode 5a are provided on the transparent substrate 13 in a state of being exposed from the sealing material 17 in a state of being insulated from each other by the light emitting functional layer 3.

Hereinafter, the details of each of the main layers for forming the above-mentioned organic EL element 100 are described in the transparent substrate 13, the transparent electrode 1, the counter electrode 5a, the light emitting layer 3c of the light emitting functional layer 3, the other layer of the light emitting functional layer 3, and the auxiliary. The electrode 15 and the sealing material 17 will be described in this order.

[Transparent board]
The transparent substrate 13 is a substrate 11 on which the transparent electrode 1 of the present invention described above is provided, and among the substrates 11 described above, the transparent substrate 11 having light transmission is used.

[Transparent electrode (anode)]
The transparent electrode 1 is the transparent electrode 1 of the present invention described above, and has a configuration in which an intermediate layer 1a and a conductive layer 1b are formed in order from the transparent substrate 13 side. Here, in particular, the transparent electrode 1 functions as an anode, and the conductive layer 1b becomes a substantial anode.

[Counter electrode (cathode)]
The counter electrode 5a is an electrode film that functions as a cathode that supplies electrons to the light emitting functional layer 3, and is composed of a metal, an alloy, an organic or inorganic conductive compound, a mixture thereof, or the like. Specifically, aluminum, silver, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, indium, lithium / aluminum mixture, rare earth metals, ITO, ZnO, TiO ₂ , Examples thereof include oxide semiconductors such as _{SnO 2.}

The counter electrode 5a can be produced by forming a thin film of these conductive materials by a method such as vapor deposition or sputtering. The sheet resistance value of the counter electrode 5a is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 5 nm to 5 μm, preferably 5 to 200 nm.

When the organic EL element 100 also extracts the emitted light h from the counter electrode 5a side, the counter electrode is made of a conductive material having good light transmission selected from the above-mentioned conductive materials. It suffices that 5a is configured.

[Light emitting layer]
The light emitting layer 3c used in the present invention contains a light emitting material, and among them, a phosphorescent compound (phosphorescent material, phosphorescent compound, phosphorescent compound) is contained as the light emitting material. Is preferable.

The light emitting layer 3c is a layer in which the electrons injected from the electrode or the electron transport layer 3d and the holes injected from the hole transport layer 3b recombine to emit light, and the light emitting portion is the light emitting layer 3c. It may be in the layer or at the interface between the light emitting layer 3c and the adjacent layer.

The configuration of such a light emitting layer 3c is not particularly limited as long as the contained light emitting material satisfies the light emitting requirements. Further, there may be a plurality of layers having the same emission spectrum and emission maximum wavelength. In this case, it is preferable to have a non-luminescent auxiliary layer (not shown) between the light emitting layers 3c.

The total layer thickness of the light emitting layer 3c is preferably in the range of 1 to 100 nm, and more preferably in the range of 1 to 30 nm because a lower driving voltage can be obtained. The total layer thickness of the light emitting layer 3c is the layer thickness including the auxiliary layer when a non-light emitting auxiliary layer is present between the light emitting layers 3c.

In the case of the light emitting layer 3c having a structure in which a plurality of layers are laminated, the layer thickness of each light emitting layer is preferably adjusted in the range of 1 to 50 nm, and more preferably adjusted in the range of 1 to 20 nm. When the plurality of laminated light emitting layers correspond to the respective light emitting colors of blue, green, and red, there is no particular limitation on the relationship between the layer thicknesses of the blue, green, and red light emitting layers.

The light emitting layer 3c configured as described above is formed by forming a light emitting material or host compound described later by a known thin film forming method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an inkjet method. Can be formed.

Further, the light emitting layer 3c may be formed by mixing a plurality of light emitting materials, or may be formed by mixing a phosphorescent compound and a fluorescent compound (fluorescent light emitting material, fluorescent dopant). ..

It is preferable that the light emitting layer 3c contains a host compound (light emitting host) and a light emitting material (light emitting dopant compound) and emits light from the light emitting material.

(Host compound)
As the host compound contained in the light emitting layer 3c, a compound having a phosphorescent quantum yield of phosphorescent emission at room temperature (25 ° C.) of less than 0.1 is preferable. More preferably, the phosphorus photon yield is less than 0.01. Further, among the compounds contained in the light emitting layer 3c, the volume ratio in the layer is preferably 50% or more.

As the host compound, a known host compound may be used alone, or a plurality of kinds may be used. By using a plurality of types of host compounds, it is possible to adjust the movement of electric charges, and it is possible to improve the efficiency of the organic EL device. Further, by using a plurality of types of light emitting materials described later, it is possible to mix different light emitting materials, whereby an arbitrary light emitting color can be obtained.

The host compound used may be a conventionally known low molecular weight compound, a high molecular weight compound having a repeating unit, or a low molecular weight compound having a polymerizable group such as a vinyl group or an epoxy group (vapor deposition polymerizable light emitting host). ..

As the known host compound, a compound having a hole transporting ability and an electron transporting ability, which prevents the wavelength of light emission from being lengthened and has a high Tg (glass transition temperature) is preferable.
The glass transition temperature referred to here is a value obtained by a method based on JIS K 7121-1987 using DSC (Differential Scanning Colorimetry).

Specific examples (H1 to H79) of the host compound that can be used in the present invention are shown below, but the present invention is not limited thereto. In addition, x and y in the host compound H68 and p, q and r in the host compound H69 represent the ratio of the random copolymer. The ratio can be, for example, x: y = 1:10 or the like.

As a specific example of the known host compound, the compounds described in the following documents can also be used. For example, Japanese Patent Application Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357977, 2002-334786, 2002-8860. Publication No. 2002-334787, No. 2002-15871, No. 2002-334788, No. 2002-43056, No. 2002-334789, No. 2002-75645, No. 2002-338579. 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227, 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183, 2002-299060, 2002. Examples thereof include Publication No. 2002-302516, Publication No. 2002-305083, Publication No. 2002-305084, and Publication No. 2002-308837.

(Luminescent material)
(1) Phosphorescent compound Examples of the light emitting material that can be used in the present invention include a phosphorescent compound.

The phosphorescent compound is a compound in which light emission from the excited triplet is observed, specifically, a compound that emits phosphorescence at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. It is defined as a compound of 0.01 or more, but a preferable phosphorescence quantum yield is 0.1 or more.

The phosphorus photon yield can be measured by the method described on page 398 (1992 edition, Maruzen) of Spectroscopy II of the 4th edition Experimental Chemistry Course 7. The phosphorescence quantum yield in a solution can be measured using various solvents, but when the phosphorescence luminescent compound is used in the present invention, the phosphorescence quantum yield (0.01 or more) is determined in any of the solvents. It should be achieved.

There are two types of luminescence principles of phosphorescent compounds.
One is that carrier recombination occurs on the host compound to which the carrier is transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent compound to emit light from the phosphorescent compound. It is an energy transfer type that obtains.
The other is a carrier trap type in which a phosphorescent compound serves as a carrier trap, carriers are recombined on the phosphorescent compound, and light emission from the phosphorescent compound is obtained. In either case, the excited state energy of the phosphorescent compound must be lower than the excited state energy of the host compound.

The phosphorescent compound can be appropriately selected from known compounds used for the light emitting layer of a general organic EL element, and preferably contains a metal of Group 8 to 10 in the periodic table of the element. It is a complex-based compound, more preferably an iridium complex, an osmium complex, a platinum complex, or a rare earth complex, and the most preferable is an iridium complex.

In the present invention, at least one light emitting layer 3c may contain two or more kinds of phosphorescent compounds, and the concentration ratio of the phosphorescent compounds in the light emitting layer 3c is in the thickness direction of the light emitting layer 3c. It may be changing.

The phosphorescent compound is preferably 0.1% by volume or more and less than 30% by volume with respect to the total amount of the light emitting layer 3c.

(1.1) Compound represented by the general formula (A) The compound (phosphorescent compound) contained in the light emitting layer 3c is preferably a compound represented by the following general formula (A).

The phosphorescent compound represented by the general formula (A) (also referred to as a phosphorescent metal complex) is preferably contained as a light emitting dopant in the light emitting layer 3c of the organic EL element 100. However, it may be contained in a light emitting functional layer other than the light emitting layer 3c.

In the general formula (A), P and Q represent carbon atoms or nitrogen atoms, respectively, and A ₁ represents a group of atoms forming an aromatic hydrocarbon ring or an aromatic heterocycle together with PCC. A ₂ represents a group of atoms forming an aromatic heterocycle with Q-N. P _1- L _1- P ₂ represents a bidentate ligand, and P ₁ and P ₂ independently represent a carbon atom, a nitrogen atom or an oxygen atom, respectively. L ₁ represents a group of atoms forming a bidentate ligand together with P ₁ and P _2. j1 represents an integer of 1 to 3 and j2 represents an integer of 0 to 2, while j1 + j2 is 2 or 3. M ₁ represents a transition metal element of Group 8 to Group 10 in the Periodic Table of the Elements.

In the general formula (A), _{the aromatic hydrocarbon rings formed by A 1} together with PC include a benzene ring, a biphenyl ring, a naphthalene ring, an azulene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a chrysen ring, and a naphthalene ring. , Triphenylene ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphene ring, coronen ring, fluorene ring, fluorantrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphene ring, pyrene ring , Pyrene ring, pyrenethrene ring, anthranetrene ring and the like.
These rings may further have a substituent represented by R ₁ in the general formula (1).

In formula (A), A ₁ is the aromatic heterocyclic ring formed together with the P-C, a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring , Benzimidazole ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, phthalazine ring, carbazole ring, aza Examples include a carbazole ring.
Here, the azacarbazole ring refers to one in which one or more carbon atoms of the benzene ring constituting the carbazole ring are replaced with nitrogen atoms.
These rings may further have a substituent represented by R ₁ in the general formula (1).

In the general formula (A) _{, examples of the aromatic heterocycle formed by A 2} together with Q-N include an oxadiazole ring, an oxadiazole ring, an oxatriazole ring, an isooxazole ring, a tetrazole ring, a thiatriazole ring, and a thiatriazole ring. Examples thereof include an isothiazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazole ring, an imidazole ring, a pyrazole ring, and a triazole ring.
These rings may further have a substituent represented by R ₁ in the general formula (1).

Examples of the bidentate ligand represented by P _1- L _1- P ₂ include phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, phenyltetrazole, pyrazabol, acetylacetone, picolinic acid and the like.

In the general formula (A), j2 represents an integer of 0 to 2, and among them, j2 is preferably 0.

In the general formula (A), M ₁ uses a transition metal element of Group 8 to 10 in the Periodic Table of the Elements (also simply referred to as a transition metal), and among them, iridium is preferable.

(1.2) Compound represented by the general formula (B) The compound represented by the general formula (A) is preferably a compound represented by the following general formula (B).

In the general formula (B), Z represents a hydrocarbon ring group or a heterocyclic group. P and Q represent carbon atoms or nitrogen atoms, respectively, and A ₁ represents a group of atoms forming an aromatic hydrocarbon ring or an aromatic heterocycle together with PCC. A ₃ represents -C (R ₀₁ ) = C (R ₀₂ )-, -N = C (R ₀₂ )-, -C (R ₀₁ ) = N- or -N = N-, and R ₀₁ , R ₀₂ represents a hydrogen atom or a substituent, respectively. P _1- L _1- P ₂ represents a bidentate ligand, and P ₁ and P ₂ independently represent a carbon atom, a nitrogen atom, or an oxygen atom. L ₁ represents a group of atoms forming a bidentate ligand together with P ₁ and P _2. j1 represents an integer of 1 to 3 and j2 represents an integer of 0 to 2, while j1 + j2 is 2 or 3. M ₁ represents a transition metal element of Group 8 to Group 10 in the Periodic Table of the Elements.

In the general formula (B), examples of the hydrocarbon ring group represented by Z include a non-aromatic hydrocarbon ring group and an aromatic hydrocarbon ring group, and examples of the non-aromatic hydrocarbon ring group include a cyclopropyl group. , Cyclopentyl group, cyclohexyl group and the like.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

Examples of the aromatic hydrocarbon ring group (also referred to as an aromatic hydrocarbon group, an aryl group, etc.) include a phenyl group, a p-chlorophenyl group, a mesityl group, a trill group, a xsilyl group, a naphthyl group, an anthryl group, and azulenyl group. Examples thereof include a group, an acenaphthenyl group, a fluorenyl group, a phenanthryl group, an indenyl group, a pyrenyl group, a biphenylyl group and the like.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

In the general formula (B), examples of the heterocyclic group represented by Z include a non-aromatic heterocyclic group, an aromatic heterocyclic group and the like, and examples of the non-aromatic heterocyclic group include an epoxy ring and aziridine. Ring, thiirane ring, oxetane ring, azetidine ring, thietan ring, tetrahydrofuran ring, dioxolan ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolan ring, thiazolidine ring, ε-caprolactone ring, ε- Caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholin Examples thereof include groups derived from a ring, a thiomorpholine-1,1-dioxide ring, a pyranose ring, a diazabicyclo [2,2,2] -octane ring and the like.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

Examples of the aromatic heterocyclic group include pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group and triazolyl group (for example, 1,2,4-triazole-1-yl). Group, 1,2,3-triazole-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isooxazolyl group, isothiazolyl group, frazayl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group. , Benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating one of the carbon atoms constituting the carbolin ring of the carbolinyl group replaced with a nitrogen atom), quinoxalinyl. Examples thereof include a group, a pyridadinyl group, a triazineyl group, a quinazolinyl group, a phthalazinyl group and the like.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

The group represented by Z is preferably an aromatic hydrocarbon ring group or an aromatic heterocyclic group.

In the general formula (B), _{the aromatic hydrocarbon rings formed by A 1} together with PC include a benzene ring, a biphenyl ring, a naphthalene ring, an azulene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, a chrysen ring, and a naphthacene ring. Ring, triphenylene ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphene ring, coronen ring, fluorene ring, fluorantrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphene ring, pyrene ring. Examples include a ring, a pyrene ring, a pyrenethrene ring, an anthranetrene ring and the like.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

In Formula (B), the aromatic heterocyclic ring A ₁ forms together with the P-C, a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, Benzimidazole ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, phthalazine ring, carbazole ring, carbazole ring. , Azacarbazole ring and the like.
Here, the azacarbazole ring refers to one in which one or more carbon atoms of the benzene ring constituting the carbazole ring are replaced with nitrogen atoms.
These groups may be unsubstituted, or may have a substituent represented by R ₁ in the general formula (1).

_{In -C (R 01} ) = C (R ₀₂ )-, -N = C (R ₀₂ )-, and -C (R ₀₁ ) = N-, which are represented by _{A 3} of the general formula (B) _{, R 01} , R ₀₂ are synonymous with the substituents represented by _{R 1} in the general formula (1).

In the general formula (B) _{, examples of the bidentate ligand represented by P 1-} L _1- P ₂ include phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, phenyltetrazole, pyrazabol, acetylacetone, picolinic acid and the like. Can be mentioned.

In the general formula (B), j2 represents an integer of 0 to 2, and among them, j2 is preferably 0.

In the general formula (B), (also referred to simply as a transition metal) group 8-10 transition metal elements in the periodic table represented by M _1, the periodic In the formula (A), represented by M ₁ It is synonymous with the transition metal elements of groups 8 to 10 in the table.

(1.3) Compound represented by the general formula (C) The compound represented by the general formula (B) is preferably a compound represented by the following general formula (C).

In the general formula (C), R ₀₃ represents a substituent, R ₀₄ represents a hydrogen atom or a substituent, and a plurality of R ₀₄ may be bonded to each other to form a ring. n01 represents an integer of 1 to 4. R ₀₅ represents a hydrogen atom or a substituent, and a plurality of R ₀₅ may be bonded to each other to form a ring. n02 represents 1 or 2. R ₀₆ represents a hydrogen atom or a substituent and may be bonded to each other to form a ring. n03 represents an integer of 1 to 4. Z ₁ represents a group of atoms required to form a six-membered aromatic hydrocarbon ring or a five- or six-membered aromatic heterocycle together with CC. Z ₂ represents a group of atoms required to form a hydrocarbon ring group or a heterocyclic group. P _1- L _1- P ₂ represents a bidentate ligand, and P ₁ and P ₂ independently represent a carbon atom, a nitrogen atom or an oxygen atom, respectively. L ₁ represents a group of atoms forming a bidentate ligand together with P ₁ and P _2. j1 represents an integer of 1 to 3 and j2 represents an integer of 0 to 2, while j1 + j2 is 2 or 3. M ₁ represents a transition metal element of Group 8 to Group 10 in the Periodic Table of the Elements. R ₀₃ and R ₀₆ , R ₀₄ and R _06, and R ₀₅ and R ₀₆ may be coupled to each other to form a ring.

In the general formula (C), the _{substituents represented by R 03} , R ₀₄ , R ₀₅ , and R ₀₆ are synonymous with the substituents represented by _{R 1} in the general formula (1).

In the general formula (C), examples of the six-membered aromatic hydrocarbon ring formed by _{Z 1 together with CC include a benzene ring and the like.}
These rings may further have a substituent, and examples of the substituent include those in the general formula (1) similar to the substituents represented by R ₁ can be mentioned.

In the general formula (C) _{, examples of the five- or six-membered aromatic heterocycle formed by Z 1} together with CC include an oxadiazole ring, an oxadiazole ring, an oxatriazole ring, an isooxazole ring, and a tetrazole ring. Examples thereof include a thiazizole ring, a thitriazole ring, an isothiazole ring, a thiophene ring, a furan ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an imidazole ring, a pyrazole ring and a triazole ring.
These rings may further have a substituent, and examples of the substituent include those in the general formula (1) similar to the substituents represented by R ₁ can be mentioned.

In the general formula (C), _{examples of the hydrocarbon ring group represented by Z 2} include a non-aromatic hydrocarbon ring group and an aromatic hydrocarbon ring group, and examples of the non-aromatic hydrocarbon ring group include cyclopropyl. Groups, cyclopentyl groups, cyclohexyl groups and the like can be mentioned.
These groups may be unsubstituted, may have a substituent, and examples of the substituent include those similar to the substituents represented by R ₁ in the general formula (1) ..

Examples of the aromatic hydrocarbon ring group (also referred to as an aromatic hydrocarbon group, an aryl group, etc.) include a phenyl group, a p-chlorophenyl group, a mesityl group, a trill group, a xsilyl group, a naphthyl group, an anthryl group, and azulenyl group. Examples thereof include a group, an acenaphthenyl group, a fluorenyl group, a phenanthryl group, an indenyl group, a pyrenyl group, a biphenylyl group and the like.
These groups may be unsubstituted, may have a substituent, and examples of the substituent include those similar to the substituents represented by R ₁ in the general formula (1) ..

In the general formula (C), _{examples of the heterocyclic group represented by Z 2} include a non-aromatic heterocyclic group, an aromatic heterocyclic group, and the like, and examples of the non-aromatic heterocyclic group include an epoxy ring. Aziridine ring, thiirane ring, oxetane ring, azetidine ring, thietan ring, tetrahydrofuran ring, dioxolan ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolan ring, thiazolidine ring, ε-caprolactone ring, ε -Caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thio Groups derived from morpholine rings, thiomorpholin-1,1-dioxide rings, pyranose rings, diazabicyclo [2,2,2] -octane rings and the like can be mentioned.
It may be these groups are unsubstituted, may have a substituent, and examples of the substituent include those in the general formula (1) similar to the substituents represented by R ₁ can be mentioned.

Examples of the aromatic heterocyclic group include pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group and triazolyl group (for example, 1,2,4-triazole-1-yl). Group, 1,2,3-triazole-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isooxazolyl group, isothiazolyl group, frazayl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group. , Benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating one of the carbon atoms constituting the carboline ring of the carbolinyl group replaced with a nitrogen atom), quinoxalinyl group , Pyridadinyl group, triazinyl group, quinazolinyl group, phthalazinyl group and the like.
May be the these rings unsubstituted, it may have a substituent, and examples of the substituent include those in the general formula (1) similar to the substituents represented by R ₁ can be mentioned.

In the general formula (C), a benzene ring is preferable as the group formed by _{Z 1} and Z _2.

In formula _(C), bidentate ligand represented by P 1 _-L 1 -P ₂ is In formula _(A), coordination of bidentate represented by P 1 _-L 1 -P ₂ It is synonymous with rank child.

In formula (C), 8 Group 10 transition metal elements of the periodic table represented by _{M 1} are the compounds of formula (A), 8 Group 10 Group in the periodic table represented by _{M 1} It is synonymous with the transition metal element of.

Further, the phosphorescent compound can be appropriately selected and used from known compounds used for the light emitting layer 3c of the organic EL element 100.

Specific examples of the phosphorescent compound according to the present invention (Pt-1 to Pt-3, A-1, Ir-1 to Ir-45) are shown below, but the present invention is not limited thereto. In these compounds, m and n represent the number of repetitions.

The above-mentioned phosphorescent compounds (also referred to as phosphorescent metal complexes and the like) are described, for example, in Organic Letters, vol3, No. 16, 2579-2581 (2001), Inorganic Chemistry, Vol. 30, No. 8, pp. 1685-1687 (1991), J. Mol. Am. Chem. Soc. , 123, 4304 (2001), Inorganic Chemistry, 40, 7, 1704-1711 (2001), Inorganic Chemistry, 41, 12, 3055-3066 (2002). , New Journal of Chemistry. , Vol. 26, p. 1171 (2002), European Journal of Organic Chemistry, Vol. 4, p. 695-709 (2004), and synthesized by applying the methods such as references described in these documents. it can.

(2) Fluorescent compounds Examples of fluorescent compounds include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, and pyrylium dyes. Examples thereof include perylene-based dyes, fluorescein-based dyes, polythiophene-based dyes, and rare earth complex-based phosphors.

[Injection layer: hole injection layer, electron injection layer]
The injection layer is a layer provided between the electrode and the light emitting layer 3c in order to reduce the driving voltage and improve the light emitting brightness. It is described in detail in Volume 2, Chapter 2, "Electrode Materials" (pages 123 to 166) of "S Co., Ltd.", and includes a hole injection layer 3a and an electron injection layer 3e.

The injection layer can be provided as needed. In the case of the hole injection layer 3a, it may be present between the anode and the light emitting layer 3c or the hole transport layer 3b, and in the case of the electron injection layer 3e, it may be present between the cathode and the light emitting layer 3c or the electron transport layer 3d. ..

The details of the hole injection layer 3a are also described in JP-A-9-45479, 9-2660062, 8-288609, etc., and as a specific example, phthalocyanine typified by copper phthalocyanine. Examples thereof include a layer, an oxide layer typified by vanadium oxide, an amorphous carbon layer, and a polymer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

The details of the electron injection layer 3e are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, etc., and specifically, typified by strontium, aluminum, and the like. Examples thereof include a metal layer, an alkali metal halide layer typified by potassium fluoride, an alkaline earth metal compound layer typified by magnesium fluoride, and an oxide layer typified by molybdenum oxide. The electron injection layer 3e is preferably a very thin film, and the layer thickness is preferably in the range of 1 nm to 10 μm, although it depends on the material.

[Hole transport layer]
The hole transport layer 3b is made of a hole transport material having a function of transporting holes, and in a broad sense, the hole injection layer 3a and the electron blocking layer are also included in the hole transport layer 3b. The hole transport layer 3b may be provided as a single layer or a plurality of layers.

The hole transporting material has either injection or transport of holes or an electron barrier property, and may be either an organic substance or an inorganic substance. For example, triazole derivatives, oxaziazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stillben derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers.

As the hole transporting material, the above-mentioned ones can be used, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Typical examples of aromatic tertiary amine compounds and styrylamine compounds are N, N, N', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'-. Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-Di-p-tolylaminophenyl) cyclohexane; N, N, N', N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N' -Di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadri Phenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4'-[4- (di-p-tolylamino) styryl] Stilben; 4-N, N-diphenyl Amino- (2-diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostillbenzene; N-phenylcarbazole, as well as the two condensed fragrances described in US Pat. No. 5,061569. Those having a group ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), triphenyl described in JP-A-4-308688. Examples thereof include 4,4', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA) in which an amine unit is linked in a three-star burst type.

Further, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. Inorganic compounds such as p-type-Si and p-type-SiC can also be used as hole injection materials and hole transport materials.

In addition, Japanese Patent Application Laid-Open No. 11-251067, J. Am. Hung et. al. , Applied Physics Letters, 80 (2002), p. So-called p-type hole transporting materials, such as those described in 139, can also be used. In the present invention, it is preferable to use these materials because a light emitting device with higher efficiency can be obtained.

The hole transport layer 3b is formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an inkjet method, or an LB method. be able to. The thickness of the hole transport layer 3b is not particularly limited, but is usually about 5 nm to 5 μm, preferably 5 to 200 nm. The hole transport layer 3b may have a one-layer structure composed of one or more of the above materials.

Further, the material of the hole transport layer 3b can be doped with impurities to increase the p property. Examples thereof include JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, J. Am. Apple. Phys. , 95, 5773 (2004) and the like.

As described above, it is preferable to increase the p property of the hole transport layer 3b because an element having lower power consumption can be manufactured.

[Electron transport layer]
The electron transport layer 3d is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer 3e and a hole blocking layer are also included in the electron transport layer 3d. The electron transport layer 3d can be provided as a single-layer structure or a multi-layer laminated structure.

As the electron transporting material (also serving as the hole blocking material) constituting the layer portion adjacent to the light emitting layer 3c in the electron transporting layer 3d having a single layer structure and the electron transporting layer 3d having a laminated structure, electrons injected from the cathode are used. It suffices to have a function of transmitting to the light emitting layer 3c. As such a material, any of conventionally known compounds can be selected and used. Examples thereof include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, carbodiimides, freolenidene methane derivatives, anthracinodimethanes, anthrone derivatives and oxadiazole derivatives. Further, among the above oxadiazole derivatives, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is replaced with a sulfur atom, and a quinoxalin derivative having a quinoxalin ring known as an electron-withdrawing group are also used as materials for the electron transport layer 3d. Can be done. Further, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

Also, metal complexes of 8-quinolinol derivatives, such as tris (8-quinolinol) aluminum (Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol). Aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metals of these metal complexes are In, Mg. , Cu, Ca, Sn, Ga or Pb can also be used as the material for the electron transport layer 3d.

In addition, metal-free or metal phthalocyanine, or those whose terminals are substituted with an alkyl group, a sulfonic acid group, or the like can also be preferably used as a material for the electron transport layer 3d. In addition, a distyrylpyrazine derivative that is also used as a material for the light emitting layer 3c can also be used as a material for the electron transport layer 3d, and is n-type-Si or n-type like the hole injection layer 3a and the hole transport layer 3b. -Inorganic semiconductors such as SiC can also be used as the material for the electron transport layer 3d.

The electron transport layer 3d can be formed by thinning the material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an inkjet method, or an LB method. The layer thickness of the electron transport layer 3d is not particularly limited, but is usually in the range of about 5 nm to 5 μm, preferably in the range of 5 to 200 nm. The electron transport layer 3d may have a one-layer structure composed of one or more of the above materials.

Further, the electron transport layer 3d can be doped with impurities to increase the n property. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, JP-A-2001-102175, J. Am. Apple. Phys. , 95, 5773 (2004) and the like. Further, it is preferable that the electron transport layer 3d contains potassium, a potassium compound, or the like. As the potassium compound, for example, potassium fluoride or the like can be used. By increasing the n property of the electron transport layer 3d in this way, it is possible to manufacture an element having lower power consumption.

Further, as the material (electron transporting compound) of the electron transporting layer 3d, the same material as the material constituting the intermediate layer 1a described above may be used. This also applies to the electron transport layer 3d that also serves as the electron injection layer 3e, and the same material as that constituting the intermediate layer 1a described above may be used.

[Blocking layer: hole blocking layer, electron blocking layer]
The blocking layer is provided as needed in addition to the basic constituent layer of the light emitting functional layer 3 described above. For example, it is described in JP-A-11-204258, No. 11-204359, and page 237 of "Organic EL Element and Its Industrialization Frontline (November 30, 1998, published by NTS Co., Ltd.)". There is a hole blocking (hole block) layer.

The hole blocking layer has a function of the electron transport layer 3d in a broad sense. The hole blocking layer is made of a hole blocking material that has a function of transporting electrons and a significantly small ability to transport holes, and recombines electrons and holes by blocking holes while transporting electrons. The probability can be improved. Further, the configuration of the electron transport layer 3d described above can be used as a hole blocking layer, if necessary. The hole blocking layer is preferably provided adjacent to the light emitting layer 3c.

On the other hand, the electron blocking layer has a function of the hole transport layer 3b in a broad sense. The electron blocking layer is made of a material that has a function of transporting holes and a significantly small ability to transport electrons, and improves the probability of recombination of electrons and holes by blocking electrons while transporting holes. be able to. Further, the structure of the hole transport layer 3b described above can be used as an electron blocking layer as needed. The thickness of the hole blocking layer is preferably in the range of 3 to 100 nm, and more preferably in the range of 5 to 30 nm.

[Auxiliary electrode]
The auxiliary electrode 15 is provided for the purpose of lowering the resistance of the transparent electrode 1, and is provided in contact with the conductive layer 1b of the transparent electrode 1. As the material for forming the auxiliary electrode 15, a metal having a low resistance such as gold, platinum, silver, copper, and aluminum is preferable. Since these metals have low light transmission, a pattern is formed within a range not affected by the extraction of the emitted light h from the light extraction surface 13a. Examples of the method for producing such an auxiliary electrode 15 include a vapor deposition method, a sputtering method, a printing method, an inkjet method, an aerosol jet method, and the like. The line width of the auxiliary electrode 15 is preferably 50 μm or less from the viewpoint of the aperture ratio for extracting light, and the thickness of the auxiliary electrode 15 is preferably 1 μm or more from the viewpoint of conductivity.

[Encapsulant]
The sealing material 17 covers the organic EL element 100, and may be a plate-shaped (film-shaped) sealing member that is fixed to the transparent substrate 13 side by the adhesive 19, and is sealed. It may be a still film. Such a sealing material 17 is provided so as to cover at least the light emitting functional layer 3 in a state where the terminal portions of the transparent electrode 1 and the counter electrode 5a in the organic EL element 100 are exposed. Further, an electrode may be provided on the sealing material 17 so that the terminal portion of the transparent electrode 1 and the counter electrode 5a of the organic EL element 100 and this electrode are made conductive.

Specific examples of the plate-shaped (film-shaped) encapsulant 17 include a glass substrate, a polymer substrate, a metal substrate, and the like, and these substrate materials may be used in the form of a thinner film. Examples of the glass substrate include soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer substrate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, polysulfone and the like. Examples of the metal substrate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium and tantalum.

Above all, since the element can be thinned, a polymer substrate or a metal substrate in the form of a thin film can be preferably used as the sealing material.

Furthermore, the polymer substrate having a film shape, the oxygen permeability was measured by the method based on JIS K 7126-1987 is ^{1 × 10 -3 ml / m 2} · 24h · atm or less, conforming to JIS K 7129-1992 was measured by the method, the water vapor transmission rate (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) is preferably one of the following ^{1 × 10 -3 g / m 2} · 24h.

Further, the substrate material as described above may be processed into an intaglio shape and used as the sealing material 17. In this case, the above-mentioned substrate material is subjected to processing such as sandblasting and chemical etching to form a concave shape.

Further, the adhesive 19 for fixing the plate-shaped sealing material 17 to the transparent substrate 13 side is for sealing the organic EL element 100 sandwiched between the sealing material 17 and the transparent substrate 13. It is used as a sealant for. Specifically, such an adhesive 19 is a photocurable and thermosetting adhesive having a reactive vinyl group of an acrylic acid-based oligomer, a methacrylic acid-based oligomer, a moisture-curable type such as 2-cyanoacrylic acid ester, and the like. Adhesives can be mentioned.
Further, heat and chemical curing type (two-component mixing) such as epoxy type, hot melt type polyamide, polyester, polyolefin, and cationic curing type ultraviolet curable epoxy resin adhesive can also be mentioned.

The organic material constituting the organic EL element 100 may be deteriorated by heat treatment. Therefore, the adhesive 19 is preferably one that can be adhesively cured from room temperature to 80 ° C. Further, the desiccant may be dispersed in the adhesive 19.

The adhesive 19 may be applied to the adhesive portion between the sealing material 17 and the transparent substrate 13 by using a commercially available dispenser or by printing as in screen printing.

Further, when a gap is formed between the plate-shaped sealing material 17, the transparent substrate 13, and the adhesive 19, in the gas phase and the liquid phase, an inert gas such as nitrogen or argon or a foot is formed in the gap. It is preferable to inject an inert liquid such as hydrogenated hydrocarbon or silicon oil. It is also possible to create a vacuum. Further, a hygroscopic compound can be enclosed inside.

Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide, etc.) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate, etc.). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide, etc.), perchlorates (eg, perchloric acid) Barium, magnesium perchlorate, etc.) and the like, and anhydrous salts are preferably used for sulfates, metal halides and perchlorates.

On the other hand, when a sealing film is used as the sealing material 17, the light emitting functional layer 3 of the organic EL element 100 is completely covered, and the terminal portions of the transparent electrode 1 and the counter electrode 5a of the organic EL element 100 are exposed. A sealing film is provided on the transparent substrate 13.

Such a sealing film is constructed by using an inorganic material or an organic material. In particular, it is made of a material having a function of suppressing the infiltration of substances such as water and oxygen that cause deterioration of the light emitting functional layer 3 in the organic EL element 100. As such a material, for example, an inorganic material such as silicon oxide, silicon dioxide, or silicon nitride is used. Further, in order to improve the brittleness of the sealing film, a film made of an organic material may be used together with the film made of these inorganic materials to form a laminated structure.

The method for producing these films is not particularly limited, and for example, vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma. A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method and the like can be used.

[Protective film, protective plate]
A protective film or a protective plate may be provided so as to sandwich the organic EL element 100 and the sealing material 17 together with the transparent substrate 13. This protective film or protective plate is for mechanically protecting the organic EL element 100, and particularly when the sealing material 17 is a sealing film, the mechanical protection for the organic EL element 100 is sufficient. Therefore, it is preferable to provide such a protective film or protective plate.

As the protective film or protective plate as described above, a glass plate, a polymer plate, a thinner polymer film, a metal plate, a thinner metal film, or a polymer material film or a metal material film is applied. Of these, it is particularly preferable to use a polymer film because it is lightweight and thin.

<Manufacturing method of organic EL element>
Here, as an example, a method for manufacturing the organic EL element 100 shown in FIG. 2 will be described.

First, on the transparent substrate 13, an intermediate layer 1a composed of an aromatic heterocyclic compound having two or more aromatic heterocyclic groups having three or more heteroatoms in the molecule is formed in a layer of 1 μm or less, preferably 10 to 100 nm. It is formed by an appropriate method such as a vapor deposition method so as to be thick. Next, the conductive layer 1b made of silver (or an alloy containing silver) is placed on the intermediate layer 1a by an appropriate method such as a vapor deposition method so that the layer thickness is in the range of 5 to 20 nm, preferably in the range of 5 to 12 nm. A transparent electrode 1 which is formed in the above and serves as an anode is produced.

Next, the hole injection layer 3a, the hole transport layer 3b, the light emitting layer 3c, the electron transport layer 3d, and the electron injection layer 3e are formed in this order to form the light emitting functional layer 3. The film formation of each of these layers includes a spin coating method, a casting method, an inkjet method, a vapor deposition method, a printing method, etc., but vacuum deposition is performed because a homogeneous film can be easily obtained and pinholes are unlikely to be formed. The method or spin coating method is particularly preferable. Further, a different film forming method may be applied for each layer. The case of employing an evaporation method in the deposition of these layers, the depositing conditions thereof are varied according to kinds of materials used, generally boat temperature 50 to 450 ° C., vacuum ¹ × 10 -6 ~1 × 10 ^-2 It is desirable to appropriately select each condition in the range of Pa, the vapor deposition rate of 0.01 to 50 nm / sec, the substrate temperature of -50 to 300 ° C., and the layer thickness of 0.1 to 5 μm.

After the light emitting functional layer 3 is formed as described above, the counter electrode 5a serving as a cathode is formed on the upper portion by an appropriate film forming method such as a vapor deposition method or a sputtering method. At this time, the counter electrode 5a forms a pattern in a shape in which the terminal portion is pulled out from above the light emitting functional layer 3 to the peripheral edge of the transparent substrate 13 while maintaining an insulating state with respect to the transparent electrode 1 by the light emitting functional layer 3. As a result, the organic EL element 100 is obtained. After that, a sealing material 17 that covers at least the light emitting functional layer 3 is provided in a state where the terminal portions of the transparent electrode 1 and the counter electrode 5a in the organic EL element 100 are exposed.

As described above, a desired organic EL element can be obtained on the transparent substrate 13. In the production of such an organic EL element 100, it is preferable to consistently produce the light emitting functional layer 3 to the counter electrode 5a by one vacuum drawing, but the transparent substrate 13 is taken out from the vacuum atmosphere in the middle of the process and is different. A membrane method may be applied. At that time, consideration must be given to performing the work in a dry inert gas atmosphere.

When a DC voltage is applied to the organic EL element 100 thus obtained, the transparent electrode 1 as the anode has a positive polarity and the counter electrode 5a as the cathode has a negative polarity, and the voltage is about 2 to 40 V. When is applied, luminescence can be observed. Further, an AC voltage may be applied. The waveform of the alternating current to be applied may be arbitrary.

<Effect of organic EL element>
The organic EL element 100 described above has a configuration in which a transparent electrode 1 having both conductivity and light transmission of the present invention is used as an anode, and a light emitting functional layer 3 and a counter electrode 5a serving as a cathode are provided above the transparent electrode 1. is there. Therefore, a sufficient voltage is applied between the transparent electrode 1 and the counter electrode 5a to realize high-luminance light emission by the organic EL element 100, and the efficiency of extracting the emitted light h from the transparent electrode 1 side is improved. It is possible to increase the brightness by this. Further, it is possible to improve the light emission life by reducing the driving voltage for obtaining a predetermined brightness.
As will be described later, the intermediate layer 1a of the present invention may be provided with an anode or a cathode, or an electron transporting layer 3d having an electron injecting property may be provided as an intermediate layer 1a in the transparent electrode 1. In particular, it is preferable that the anode not involved in light emission includes the intermediate layer 1a because the layer thickness can be appropriately changed.

≪4. Second example of organic EL element ≫
<Structure of organic EL element>
FIG. 3 is a schematic cross-sectional view showing a second example of the organic EL element using the transparent electrode 1 described above as an example of the electronic device of the present invention. The difference between the organic EL element 200 of the second example shown in FIG. 3 and the organic EL element 100 of the first example shown in FIG. 2 is that the transparent electrode 1 is used as a cathode. Hereinafter, the overlapping detailed description of the same components as in the first example will be omitted, and the characteristic configuration of the organic EL element 200 in the second example will be described.

As shown in FIG. 3, the organic EL element 200 is provided on the transparent substrate 13, and similarly to the first example, the transparent electrode 1 of the present invention described above is used as the transparent electrode 1 on the transparent substrate 13. ing. Therefore, the organic EL element 200 is configured so that the emitted light h can be extracted from at least the transparent substrate 13 side. However, the transparent electrode 1 is used as a cathode. Therefore, the counter electrode 5b is used as an anode.

The layer structure of the organic EL element 200 configured in this way is not limited to the examples described below, and may be a general layer structure, as in the first example.

As an example of the second example, the electron injection layer 3e / electron transport layer 3d / light emitting layer 3c / hole transport layer 3b / hole injection layer 3a are laminated in this order on the transparent electrode 1 that functions as a cathode. The configuration is illustrated. However, it is essential to have at least a light emitting layer 3c made of an organic material.

In addition to these layers, the light emitting functional layer 3 adopts various configurations as required, as described in the first example. In such a configuration, it is the same as the first example that only the portion where the light emitting functional layer 3 is sandwiched between the transparent electrode 1 and the counter electrode 5b becomes the light emitting region in the organic EL element 200.

Further, in the layer structure as described above, the auxiliary electrode 15 may be provided in contact with the conductive layer 1b of the transparent electrode 1 for the purpose of reducing the resistance of the transparent electrode 1. Similar to the example.

Here, the counter electrode 5b used as the anode is composed of a metal, an alloy, an organic or inorganic conductive compound, a mixture thereof, or the like. Specific examples thereof include metals such as gold (Au), oxide semiconductors such as _{copper iodide (CuI), ITO, ZnO, TiO 2} and SnO _2.

The counter electrode 5b configured as described above can be manufactured by forming a thin film of these conductive materials by a method such as vapor deposition or sputtering. The sheet resistance value of the counter electrode 5b is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 5 nm to 5 μm, preferably 5 to 200 nm.

When the organic EL element 200 is configured so that the emitted light h can be taken out from the counter electrode 5b side as well, the material constituting the counter electrode 5b has good light transmission among the above-mentioned conductive materials. Conductive material is selected and used.

The organic EL element 200 having the above configuration is sealed with a sealing material 17 as in the first example for the purpose of preventing deterioration of the light emitting functional layer 3.

Among the main layers constituting the organic EL element 200 described above, the detailed configuration of the components other than the counter electrode 5b used as the anode and the manufacturing method of the organic EL element 200 are the same as those in the first example. Therefore, detailed description thereof will be omitted.

<Effect of organic EL element>
The organic EL element 200 described above has a configuration in which a transparent electrode 1 having both conductivity and light transmission of the present invention is used as a cathode, and a light emitting functional layer 3 and a counter electrode 5b serving as an anode are provided above the transparent electrode 1. is there. Therefore, as in the first example, a sufficient voltage is applied between the transparent electrode 1 and the counter electrode 5b to realize high-luminance light emission in the organic EL element 200, and the light emitted from the transparent electrode 1 side. It is possible to increase the brightness by improving the extraction efficiency of h. Further, it is possible to improve the light emission life by reducing the driving voltage for obtaining a predetermined brightness.

≪5. Third example of organic EL element ≫
<Structure of organic EL element>
FIG. 4 is a schematic cross-sectional view showing a third example of the organic EL element using the transparent electrode 1 described above as an example of the electronic device of the present invention. The difference between the organic EL element 300 of the third example shown in FIG. 4 and the organic EL element 100 of the first example shown in FIG. 2 is that a counter electrode 5c is provided on the substrate 131 side, and a light emitting functional layer 3 is provided above the counter electrode 5c. The transparent electrodes 1 are laminated in this order. Hereinafter, the overlapping detailed description of the same components as in the first example will be omitted, and the characteristic configuration of the organic EL element 300 in the third example will be described.

The organic EL element 300 shown in FIG. 4 is provided on the substrate 131, and the counter electrode 5c serving as the anode, the light emitting functional layer 3 and the transparent electrode 1 serving as the cathode are laminated in this order from the substrate 131 side. .. Of these, the transparent electrode 1 of the present invention described above is used as the transparent electrode 1. Therefore, the organic EL element 300 is configured so that the emitted light h can be extracted from at least the transparent electrode 1 side opposite to the substrate 131.

The layer structure of the organic EL element 300 configured in this way is not limited to the examples described below, and may be a general layer structure, as in the first example.

As an example of the case of the third example, a configuration in which a hole injection layer 3a / a hole transport layer 3b / a light emitting layer 3c / an electron transport layer 3d are laminated in this order is exemplified on an upper portion of a counter electrode 5c that functions as an anode. To. However, it is essential to have at least a light emitting layer 3c constructed by using an organic material. Further, the electron transport layer 3d also serves as an electron injection layer 3e, and is provided as an electron transport layer 3d having an electron injection property.

In particular, as a characteristic configuration of the organic EL element 300 of the third example, an electron transport layer 3d having an electron injecting property is provided as an intermediate layer 1a in the transparent electrode 1. That is, in the third example, the transparent electrode 1 used as a cathode is composed of an intermediate layer 1a that also serves as an electron transporting layer 3d having electron injectability, and a conductive layer 1b provided above the intermediate layer 1a. Is.

Such an electron transport layer 3d is constructed by using the material constituting the intermediate layer 1a of the transparent electrode 1 described above.

In addition to these layers, the light emitting functional layer 3 adopts various configurations as required as described in the first example, but electron transport that also serves as the intermediate layer 1a of the transparent electrode 1. No electron injection layer or hole blocking layer is provided between the layer 3d and the conductive layer 1b of the transparent electrode 1. In the above configuration, it is the same as the first example that only the portion where the light emitting functional layer 3 is sandwiched between the transparent electrode 1 and the counter electrode 5c becomes the light emitting region in the organic EL element 300.

Further, in the layer structure as described above, the auxiliary electrode 15 may be provided in contact with the conductive layer 1b of the transparent electrode 1 for the purpose of reducing the resistance of the transparent electrode 1. It is the same as one example.

Further, the counter electrode 5c used as an anode is composed of a metal, an alloy, an organic or inorganic conductive compound, a mixture thereof, or the like. Specific examples thereof include metals such as gold (Au), oxide semiconductors such as _{copper iodide (CuI), ITO, ZnO, TiO 2} and SnO _2.

The counter electrode 5c configured as described above can be manufactured by forming a thin film of these conductive materials by a method such as vapor deposition or sputtering. The sheet resistance value of the counter electrode 5c is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 5 nm to 5 μm, preferably 5 to 200 nm.

When the organic EL element 300 is configured so that the emitted light h can be taken out from the counter electrode 5c side as well, the material constituting the counter electrode 5c has good light transmission among the above-mentioned conductive materials. Conductive material is selected and used. Further, in this case, as the substrate 131, the same substrate as the transparent substrate 13 described in the first example is used.

The organic EL element 300 having the above configuration is sealed with a sealing material 17 as in the first example for the purpose of preventing deterioration of the light emitting functional layer 3. Further, in the organic EL element 300, the surface of the sealing material 17 that is substantially parallel to the substrate 131 and that is opposite to the organic EL element 300 is the light extraction surface 17a.

<Effect of organic EL element>
In the organic EL element 300 described above, the electron transporting layer 3d having an electron injecting property forming the uppermost portion of the light emitting functional layer 3 is used as an intermediate layer 1a, and the conductive layer 1b is provided on the intermediate layer 1a. The transparent electrode 1 formed of the upper conductive layer 1b is provided as a cathode. Therefore, as in the first and second examples, a sufficient voltage is applied between the transparent electrode 1 and the counter electrode 5c to realize high-luminance light emission in the organic EL element 300, and the transparent electrode 1 side. It is possible to increase the brightness by improving the extraction efficiency of the emitted light h from the light emitting light h. Further, it is possible to improve the light emission life by reducing the driving voltage for obtaining a predetermined brightness. Further, when the counter electrode 5c has light transmission property, the emitted light h can be extracted from the counter electrode 5c as well.

In the third example described above, it has been described that the intermediate layer 1a of the transparent electrode 1 also serves as the electron transport layer 3d having electron injectability, but this example is not limited to this, and the intermediate layer is not limited to this. 1a may also serve as an electron-transporting layer 3d having no electron-injecting property, or the intermediate layer 1a may also serve as an electron-injecting layer instead of an electron-transporting layer. Further, the intermediate layer 1a may be formed as an ultrathin film that does not affect the light emitting function of the organic EL element. In this case, the intermediate layer 1a has electron transporting property and electron injecting property. Not.

Further, when the intermediate layer 1a of the transparent electrode 1 is formed as an ultrathin film that does not affect the light emitting function of the organic EL element, the counter electrode 5c on the substrate 131 side is used as a cathode on the light emitting function layer 3. The transparent electrode 1 of the above may be used as an anode. In this case, the light emitting functional layer 3 is formed in order from the counter electrode (cathode) 5c side on the substrate 131, for example, electron injection layer 3e / electron transport layer 3d / light emitting layer 3c / hole transport layer 3b / hole injection layer 3a. Are laminated. A transparent electrode 1 having a laminated structure of an extremely thin intermediate layer 1a and a conductive layer 1b is provided on the upper portion as an anode.

≪6. Applications of organic EL elements ≫
Since the organic EL element having each of the above-described configurations is a surface-emitting body as described above, it can be used as various light-emitting light sources. For example, lighting devices such as household lighting and interior lighting, backlights for clocks and liquid crystals, lighting for signage advertisements, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, etc. Examples include the light source of an optical sensor. In particular, it can be effectively used as a backlight of a liquid crystal display device combined with a color filter and a light source for lighting.

Further, the organic EL element of the present invention may be used as a kind of lamp such as for lighting or an exposure light source, a projection device of a type for projecting an image, or a type for directly visually recognizing a still image or a moving image. It may be used as a display device (display). In this case, with the recent increase in size of lighting devices and displays, the area of the light emitting surface may be increased by so-called tiling, in which light emitting panels provided with organic EL elements are joined in a plane.

When used as a display device for video reproduction, the drive system may be either a simple matrix (passive matrix) system or an active matrix system. Further, a color or full-color display device can be manufactured by using two or more kinds of organic EL elements of the present invention having different emission colors.

In the following, a lighting device will be described as an example of its application, and then a lighting device in which the light emitting surface has a large area by tiling will be described.

≪6-1. Lighting device-1 >>
The lighting device can be equipped with the organic EL element of the present invention.

The organic EL element used in the lighting device may be designed so that each organic EL element having the above-described configuration has a resonator structure. The purpose of use of the organic EL element configured to have a resonator structure includes a light source of an optical storage medium, a light source of an electrophotographic copying machine, a light source of an optical communication processor, a light source of an optical sensor, and the like. Not limited to. Further, it may be used for the above purpose by oscillating a laser.

The material used for the organic EL element of the present invention can be applied to an organic EL element (white organic EL element) that emits substantially white light. For example, it is possible to simultaneously emit a plurality of emission colors with a plurality of light emitting materials and obtain white emission by mixing the colors. The combination of a plurality of emission colors may include three emission maximum wavelengths of the three primary colors of red, green, and blue, or two emissions using the relationship of complementary colors such as blue and yellow and blue-green and orange. It may contain a maximum wavelength.

The combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or phosphorescent materials, a light emitting material that emits fluorescence or phosphorescence, and an excitation of light from the light emitting material. Any combination with a dye material that emits light as light may be used, but in the white organic EL element, a plurality of light emitting dopants may be combined and mixed.

Such a white organic EL element is different from the configuration in which the organic EL elements of each color emission are individually arranged in parallel in an array to obtain white emission, and the organic EL element itself emits white light. Therefore, a mask is not required for film formation of most of the layers constituting the element, and film formation can be performed on one surface by a thin film deposition method, a casting method, a spin coating method, an inkjet method, a printing method, etc., and productivity is also improved. To do.

Further, the light emitting material used for the light emitting layer of such a white organic EL element is not particularly limited, and for example, a backlight in a liquid crystal display element is adapted to a wavelength range corresponding to CF (color filter) characteristics. In addition, any of the above-mentioned metal complexes and known light-emitting materials may be selected and combined for whitening.

By using the white organic EL element described above, it is possible to manufacture a lighting device that emits substantially white light.

≪6-2. Lighting device-2 >>
FIG. 5 is a schematic cross-sectional view of an illuminating device in which a plurality of organic EL elements having the above configurations are used to increase the area of the light emitting surface.
As shown in FIG. 5, the lighting device 21 has a large area of the light emitting surface by arranging (tiling) a plurality of light emitting panels 22 having the organic EL element 100 on the transparent substrate 13 on the support substrate 23. It is a modified configuration. The support substrate 23 may also serve as a sealing material 17, and each light emitting panel 22 is tied with the organic EL element 100 sandwiched between the support substrate 23 and the transparent substrate 13 of the light emitting panel 22. Ring. An adhesive 19 may be filled between the support substrate 23 and the transparent substrate 13, thereby sealing the organic EL element 100. The ends of the transparent electrode 1 as the anode and the counter electrode 5a as the cathode are exposed around the light emitting panel 22. However, in FIG. 5, only the exposed portion of the counter electrode 5a is shown.
In FIG. 5, as the light emitting functional layer 3 constituting the organic EL element 100, the hole injection layer 3a / hole transport layer 3b / light emitting layer 3c / electron transport layer 3d / electron injection layer 3e are placed on the transparent electrode 1. Are shown as an example in a configuration in which the above are sequentially laminated.

In the lighting device 21 having such a configuration, the center of each light emitting panel 22 is the light emitting region A, and the non-light emitting region B is generated between the light emitting panels 22. Therefore, a light extraction member for increasing the amount of light extracted from the non-light emitting region B may be provided in the non-light emitting region B of the light extraction surface 13a. As the light extraction member, a light condensing sheet or a light diffusion sheet can be used.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

[Example 1]
<< Fabrication of transparent electrode >>
As described below, the transparent electrodes 1-1 to 1-19 were manufactured so that the area of the conductive region was 5 cm × 5 cm. The transparent electrodes 1-1 to 1-4 are manufactured as transparent electrodes having a single-layer structure consisting of only a conductive layer, and the transparent electrodes 1 to 5 to 1-19 are transparent with a laminated structure of an intermediate layer and a conductive layer. Made as an electrode.

(1) Preparation of Transparent Electrode 1-1 First, a transparent non-alkali glass substrate was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus and attached to a vacuum chamber of the vacuum vapor deposition apparatus. Further, a tungsten resistance heating board was filled with silver (Ag) and installed in the vacuum chamber. Next, after depressurizing the vacuum chamber to 4 × 10 ^-4 Pa, the resistance heating board is energized and heated, and the layer thickness is 5 nm on the substrate within the vapor deposition rate of 0.1 to 0.2 nm / sec. A conductive layer made of silver was formed to form a transparent electrode 1-1 having a single-layer structure.

(2) Preparation of Transparent Electrode 1-2 to 1-4 In the production of the transparent electrode 1-1, the transparent electrode 1-2 is similarly formed except that the thickness of the conductive layer is changed to 8 nm, 10 nm, and 15 nm, respectively. ~ 1-4 were prepared.

(3) Preparation of Transparent Electrode 1-5 A transparent non-alkali glass substrate is fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus, and the compound I-47 of the present invention is filled in a tantalum resistance heating board. The substrate holder and the heating board were attached to the first vacuum chamber of the vacuum vapor deposition apparatus. Further, a tungsten resistance heating board was filled with silver and installed in a second vacuum chamber.

In this state, first, the first vacuum chamber ^{was depressurized to 4 × 10 -4} Pa, and then the heating board containing the compound I-47 was energized and heated, and the vapor deposition rate was 0.1 to 0.2 nm / sec. Within the range, an intermediate layer made of compound I-47 having a layer thickness of 20 nm was provided on the substrate.

Next, the substrate on which the film was formed up to the intermediate layer was transferred to the second vacuum chamber in a vacuum, the second vacuum chamber ^{was depressurized to 4 × 10 -4} Pa, and then a heating board containing silver was energized to heat it. A conductive layer made of silver having a layer thickness of 5 nm was formed within a vapor deposition rate of 0.1 to 0.2 nm / sec, and a transparent electrode 1-5 having a laminated structure of an intermediate layer and a conductive layer was produced. ..

(4) Preparation of Transparent Electrodes 1-6 to 1-8 In the production of the transparent electrode 5, the transparent electrodes 1-6 to 1 are similarly formed except that the thickness of the conductive layer is changed to 8 nm, 10 nm, and 15 nm, respectively. -8 was prepared.

(5) Preparation of Transparent Electrodes 1-9 to 1-16 In the production of transparent electrodes 1-6, the transparent electrodes 1-9 are similarly prepared except that the constituent materials of the intermediate layers are changed to the compounds shown in Table 1. ~ 1-16 was prepared.

(6) Preparation of transparent electrodes 1-17 to 1-19 In the production of transparent electrodes 1-17 to 1-19, the transparent electrodes are similarly prepared except that the substrate is changed from non-alkali glass to PET (polyethylene terephthalate) film. 1-17 to 1-19 were prepared.

<< Evaluation of transparent electrode >>
With respect to the produced transparent electrodes 1-1 to 1-19, the element transmittance, the sheet resistance value and the durability (electrode life) were measured according to the following methods.

(1) Measurement of light transmittance For each of the manufactured transparent electrodes, the light transmittance (%) at a wavelength of 550 nm was measured using a spectrophotometer (U-3300 manufactured by Hitachi, Ltd.) with the substrate of each transparent electrode as a reference. .. The measurement results are shown in Table 1.

(2) Measurement of sheet resistance value For each of the manufactured transparent electrodes, the sheet resistance value (Ω / □) was measured using a resistivity meter (MCP-T610 manufactured by Mitsubishi Chemical Co., Ltd.) by a 4-probe method constant current application method.
The measurement results are shown in Table 1.

(3) Measurement of electrode life under constant current Measure the time required for the sheet resistance value to become twice the initial value by continuing to apply a constant current of 10 A to each of the manufactured transparent electrodes in the atmosphere. did.
The measurement results are shown in Table 1.
The electrode life is shown as a relative value with the electrode life of the transparent electrodes 1-4 as 100.

(4) Summary As is clear from Table 1, the transparent electrodes 1-5 to 1-19 of the present invention are provided with a conductive layer containing silver (Ag) as a main component on an intermediate layer using the compound of the present invention. All have good light transmittance and the sheet resistance value is kept low. On the other hand, it can be seen that the transparent electrodes 1-1 to 1-4 of the comparative example all have low light transmittance and high sheet resistance value.
It can also be seen that the transparent electrodes 1-5 to 1-19 of the present invention are superior in durability (electrode life) to the transparent electrodes 1-1 to 1-4 of the comparative example.

From the above, it was confirmed that the transparent electrode of the present invention has both high light transmittance and conductivity and is excellent in durability.

[Example 2]
<< Fabrication of light emitting panel >>
Double-sided light emitting panels 2-1 to 2-19 were produced using a transparent electrode produced in the same manner as in Example 1 as an anode. Hereinafter, the manufacturing procedure will be described with reference to FIG.

(1) Preparation of Light Emitting Panel 2-1 First, the transparent substrate 13 on which the transparent electrode 1 having only the conductive layer 1b, which was produced in Example 1, was formed, was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus. A thin-film deposition mask was placed facing each other on the forming surface side of the transparent electrode 1. In addition, each of the heating boards in the vacuum vapor deposition apparatus was filled with each material constituting the light emitting functional layer 3 in an optimum amount for film formation of each layer. The heating board used was made of a tungsten resistance heating material.

Next, the vapor deposition chamber of the vacuum vapor deposition apparatus ^{was depressurized to a degree of vacuum of 4 × 10 -4} Pa, and a heating board containing each material was sequentially energized and heated to form a film of each layer as follows.

First, as a hole transport injection material, a heating board containing α-NPD shown in the following structural formula is energized and heated, and hole transport injection that also serves as a hole injection layer and a hole transport layer made of α-NPD is performed. The layer 31 was formed on the conductive layer 1b constituting the transparent electrode 1. At this time, the vapor deposition rate was 0.1 to 0.2 nm / sec and the layer thickness was 20 nm.

Next, the heating board containing the host material H4 and the heating board containing the phosphorescent compound Ir-4 are independently energized, and the host material H4 and the phosphorescent compound Ir-4 emit light. The layer 3c was formed on the hole transport injection layer 31. At this time, the energization of the heating board was adjusted so that the vapor deposition rate was the host material H4: phosphorescent compound Ir-4 = 100: 6. The layer thickness was 30 nm.

Next, a heating board containing BAlq represented by the following structural formula as a hole blocking material was energized and heated to form a hole blocking layer 33 made of BAlq on the light emitting layer 3c. At this time, the vapor deposition rate was 0.1 to 0.2 nm / sec and the layer thickness was 10 nm.

After that, the heating board containing ET-4 shown in the following structural formula and the heating board containing potassium fluoride are independently energized as electron transport materials, and electron transport consisting of ET-4 and potassium fluoride is performed. The layer 3d was formed on the hole blocking layer 33. At this time, the energization of the heating board was adjusted so that the vapor deposition rate was ET-4: potassium fluoride = 75:25. The layer thickness was 30 nm.

Next, a heating board containing potassium fluoride as an electron injection material was energized and heated to form an electron injection layer 3e made of potassium fluoride on the electron transport layer 3d. At this time, the vapor deposition rate was 0.01 to 0.02 nm / sec, and the layer thickness was 1 nm.

After that, the transparent substrate 13 formed up to the electron injection layer 3e was moved from the vapor deposition chamber of the vacuum vapor deposition apparatus to the processing chamber of the sputtering apparatus to which the ITO target was attached as the counter electrode material while maintaining the vacuum state. .. Next, in the processing chamber, a film was formed using a light-transmitting counter electrode 5a made of ITO having a layer thickness of 150 nm as a cathode at a film formation rate of 0.3 to 0.5 nm / sec. As described above, the organic EL element 400 is formed on the transparent substrate 13.

After that, the organic EL element 400 is covered with a sealing material 17 made of a glass substrate having a thickness of 300 μm, and the adhesive 19 (sealing material) is placed between the sealing material 17 and the transparent substrate 13 in a state of surrounding the organic EL element 400. ) Was filled. As the adhesive 19, an epoxy-based photocurable adhesive (Luxtrac LC0629B manufactured by Toagosei Co., Ltd.) was used. The adhesive 19 filled between the sealing material 17 and the transparent substrate 13 is irradiated with UV light from the glass substrate (sealing material 17) side to cure the adhesive 19 and seal the organic EL element 400. I stopped.

In the formation of the organic EL element 400, a thin-film mask is used to form each layer, and the central 4.5 cm × 4.5 cm of the transparent substrate 13 of 5 cm × 5 cm is set as the light emitting region A, and the entire circumference of the light emitting region A is set. A non-emissive region B having a width of 0.25 cm was provided in the above. Further, the transparent electrode 1 as the anode and the counter electrode 5a as the cathode are in a state of being insulated by the light emitting functional layer 3 from the hole transport injection layer 31 to the electron injection layer 3e, and the terminal portion is formed on the peripheral edge of the transparent substrate 13. Was formed in a pulled-out shape.

As described above, the organic EL element 400 was provided on the transparent substrate 13, and the light emitting panel 2-1 was prepared by sealing the organic EL element 400 with the sealing material 17 and the adhesive 19.
In the light emitting panel 2-1 the light emitting light h of each color generated in the light emitting layer 3c is taken out from both the transparent electrode 1 side, that is, the transparent substrate 13 side, and the counter electrode 5a side, that is, the sealing material 17 side.

(2) Preparation of light emitting panel 2-2-2-2-19 In the production of the light emitting panel 2-1 in the same manner except that the transparent electrode shown in Table 2 was used, the light emitting panel 2-2-2-16 was formed in the same manner. Made.
Further, in the production of the light emitting panels 2-17 to 2-19, the light emitting panels 2-17 to 2-19 were produced in the same manner except that the substrate was changed from non-alkali glass to PET (polyethylene terephthalate) film.

<< Evaluation of light emitting panel >>
With respect to the produced light emitting panels 2-1 to 2-19, the light transmittance, the driving voltage, and the durability (luminance half life) were measured according to the following methods.

(1) Measurement of light transmittance For each light emitting panel manufactured, a spectrophotometer (U-3300 manufactured by Hitachi, Ltd.) was used, and the light transmittance (%) at a wavelength of 550 nm was used as a reference with the substrate of the transparent electrode of each light emitting panel as a reference. Was measured.
The measurement results are shown in Table 2.

(2) Measurement of drive voltage For each light emitting panel produced, the front luminance on both sides of the transparent electrode 1 side (that is, the transparent substrate 13 side) and the counter electrode 5a side (that is, the sealing material 17 side) of each light emitting panel. Was measured, and the voltage when the sum was 1000 cd / m ² was measured as the drive voltage (V). A spectral radiance meter CS-1000 (manufactured by Konica Minolta) was used for the measurement of the brightness. The smaller the value of the obtained drive voltage, the more preferable the result.
The measurement results are shown in Table 2.

(3) Measurement of half-luminance life The ^{time required for each of the manufactured light-emitting panels to continuously emit light under a constant current condition of 2.5} mA / cm 2 at room temperature to achieve half the brightness of the initial brightness (τ1 / 2). ) Was measured.
The measurement results are shown in Table 2.
The luminance half-life is shown as a relative value with the luminance half-life of the light emitting panel 2-4 as 100.

(4) Summary As is clear from Table 2, all of the light emitting panels 2-5 to 2-19 of the present invention using the transparent electrode of the present invention as the anode of the organic EL element have good light transmittance. Moreover, it can be seen that the drive voltage is kept low.
It can also be seen that the light emitting panels 2-5 to 2-19 of the present invention are superior to the light emitting panels 2-1 to 2-4 of the comparative example in terms of durability (luminance half life).

As a result, it was confirmed that the light emitting panel using the transparent electrode of the present invention can emit high-intensity light with a low driving voltage. It was also confirmed that this is expected to reduce the drive voltage for obtaining a predetermined brightness and improve the light emission life.

[Example 3]
<< Production of light emitting panel 3-1 >>
A double-sided light emitting panel 3-1 to 3-19 was produced using a transparent electrode produced in the same manner as in Example 1 as a cathode (opposite electrode 5a). The production procedure will be described below.

(1) Preparation of light emitting panel 3-1 On a glass substrate of 100 mm × 100 mm × 1.1 mm, patterning was performed on a substrate (NA-45 manufactured by AvanStrate Inc.) in which ITO (indium tin oxide) was deposited at 100 nm as an anode. went. Then, the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed for 5 minutes.
The transparent substrate 13 was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus, and a vapor deposition mask was placed facing the formation surface side of the transparent electrode 1. In addition, each of the heating boards in the vacuum vapor deposition apparatus was filled with each material constituting the light emitting functional layer 3 in an optimum amount for film formation of each layer. The heating board used was made of a tungsten resistance heating material.

Next, the vapor deposition chamber of the vacuum vapor deposition apparatus ^{was depressurized to a degree of vacuum of 4 × 10 -4} Pa, and a heating board containing each material was sequentially energized and heated to form a film of each layer as follows.

First, a heating board containing α-NPD as a hole transport injection material is energized and heated, and the hole transport injection layer 31 composed of α-NPD and also serves as a hole transport layer is transparent. A film was formed on the conductive layer 1b constituting the electrode 1. At this time, the vapor deposition rate was 0.1 to 0.2 nm / sec and the layer thickness was 20 nm.

Next, the heating board containing the host material H4 and the heating board containing the phosphorescent compound Ir-4 are independently energized, and the host material H4 and the phosphorescent compound Ir-4 emit light. The layer 3c was formed on the hole transport injection layer 31. At this time, the energization of the heating board was adjusted so that the vapor deposition rate was the host material H4: phosphorescent compound Ir-4 = 100: 6. The layer thickness was 30 nm.

Next, a heating board containing BAlq as a hole blocking material was energized and heated to form a hole blocking layer 33 made of BAlq on the light emitting layer 3c. At this time, the vapor deposition rate was 0.1 to 0.2 nm / sec and the layer thickness was 10 nm.

After that, the heating board containing ET-6 shown in the following structural formula and the heating board containing potassium fluoride are independently energized as electron transport materials, and electron transport consisting of ET-6 and potassium fluoride is performed. The layer 3d was formed on the hole blocking layer 33. At this time, the energization of the heating board was adjusted so that the vapor deposition rate was ET-6: potassium fluoride = 75:25. The layer thickness was 30 nm.

Next, a heating board containing potassium fluoride as an electron injection material was energized and heated to form an electron injection layer 3e made of potassium fluoride on the electron transport layer 3d. At this time, the vapor deposition rate was 0.01 to 0.02 nm / sec, and the layer thickness was 1 nm.

Then, the transparent substrate 13 formed up to the electron injection layer 3e was moved from the vapor deposition chamber of the vacuum vapor deposition apparatus to the processing chamber of the sputtering apparatus to which Ag was attached as the counter electrode material while maintaining the vacuum state. Next, in the same manner as in Example 1, a conductive layer 1b was used as a cathode as a light-transmitting counter electrode 5a made of Ag having a layer thickness of 5 nm at a film formation rate of 0.1 to 0.2 nm / sec. A film was formed. As described above, the organic EL element 400 is formed on the transparent substrate 13.

After that, the organic EL element 400 is covered with a sealing material 17 made of a glass substrate having a thickness of 300 μm, and an adhesive 19 (seal material) is placed between the sealing material 17 and the transparent substrate 13 in a state of surrounding the organic EL element 400. ) Was filled. As the adhesive 19, an epoxy-based photocurable adhesive (Luxtrac LC0629B manufactured by Toagosei Co., Ltd.) was used. The adhesive 19 filled between the sealing material 17 and the transparent substrate 13 is irradiated with UV light from the glass substrate (sealing material 17) side to cure the adhesive 19 and seal the organic EL element 400. I stopped.

In the formation of the organic EL element 400, a thin-film mask is used to form each layer, and the central 4.5 cm × 4.5 cm of the transparent substrate 13 of 5 cm × 5 cm is set as the light emitting region A, and the entire circumference of the light emitting region A is set. A non-emissive region B having a width of 0.25 cm was provided in the above. Further, the counter electrode 5a composed of the ITO transparent electrode 1 as the anode and the Ag as the cathode is insulated from the light emitting functional layer 3 from the hole transport injection layer 31 to the electron injection layer 3e on the transparent substrate 13. The terminal portion was formed in a pulled-out shape on the peripheral edge.

As described above, the organic EL element 400 was provided on the transparent substrate 13, and the light emitting panel 2-1 was prepared by sealing the organic EL element 400 with the sealing material 17 and the adhesive 19.
In the light emitting panel 1, the light emitted h of each color generated in the light emitting layer 3c is taken out from both the transparent electrode 1 side, that is, the transparent substrate 13 side, and the counter electrode 5a side, that is, the sealing material 17 side.

(2) Preparation of light emitting panel 3-2-3-19 In the production of the light emitting panel 3-1 in the same manner except that the counter electrode 5a was changed to the transparent electrode shown in Table 3, the light emitting panel 3-2-3- 16 was made.
Further, in the production of the light emitting panels 3-17 to 3-19, the light emitting panels 3-17 to 3-19 were produced in the same manner except that the substrate was changed from non-alkali glass to PET (polyethylene terephthalate) film.

<< Evaluation of light emitting panel >>
With respect to the produced light emitting panel 3-2-3-19, the light transmittance, the driving voltage, and the half-luminance life were measured according to the following methods.

(1) Measurement of light transmittance For each light emitting panel manufactured, a spectrophotometer (U-3300 manufactured by Hitachi, Ltd.) was used, and the light transmittance (%) at a wavelength of 550 nm was used as a reference with the substrate of the transparent electrode of each light emitting panel as a reference. Was measured.
The measurement results are shown in Table 3.

(2) Measurement of drive voltage For each light emitting panel produced, the front luminance on both sides of the transparent electrode 1 side (that is, the transparent substrate 13 side) and the counter electrode 5a side (that is, the sealing material 17 side) of each light emitting panel. Was measured, and the voltage when the sum was 1000 cd / m ² was measured as the drive voltage (V). A spectral radiance meter CS-1000 (manufactured by Konica Minolta) was used for the measurement of the brightness. The smaller the value of the obtained drive voltage, the more preferable the result.
The measurement results are shown in Table 3.

(3) Measurement of half-luminance life The ^{time required for each of the manufactured light-emitting panels to continuously emit light under a constant current condition of 2.5} mA / cm 2 at room temperature to achieve half the brightness of the initial brightness (τ1 / 2). ) Was measured.
The measurement results are shown in Table 3.
The luminance half-life is shown as a relative value with the luminance half-life of the light emitting panel 3-4 as 100.

(4) Summary As is clear from Table 3, all of the light emitting panels 3-5 to 3-19 using the transparent electrode of the present invention as the cathode of the organic EL element have good light transmittance and drive voltage. Is kept low.
It can also be seen that the light emitting panels 3-5 to 3-19 are superior to the light emitting panels 3 to 3 to 4 of the comparative example in terms of durability (luminance half life).

As a result, it was confirmed that the light emitting panel using the transparent electrode of the present invention can emit high-intensity light with a low driving voltage. It was also confirmed that this is expected to reduce the drive voltage for obtaining a predetermined brightness and improve the light emission life.

1 Transparent electrode 1a Intermediate layer 1b Conductive layer 3 Light emitting functional layer 3a Hole injection layer 3b Hole transport layer 3c Light emitting layer 3d Electron transport layer 3e Electron injection layer 5a, 5b, 5c Opposite electrode 11 Substrate 13, 131 Transparent substrate ( substrate)
13a, 17a Light extraction surface 15 Auxiliary electrode 17 Encapsulant 19 Adhesive 21 Lighting device 22 Light emitting panel 23 Support substrate 31 Hole transport injection layer 33 Hole blocking layer 100, 200, 300, 400 Organic EL element A Light emitting region B Non-emission area h Emission light

Claims (8)

An intermediate layer, a transparent electrode and a deposited electrically conductive layer adjacent to on the intermediate layer,
The conductive layer contains silver as a main component and contains silver as a main component.
The intermediate layer is a transparent electrode containing an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms. The transparent electrode according to claim 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (1).

[In the general formula (1), E _{1 to} E ₆ represent carbon atoms or nitrogen atoms, and at least two of them represent carbon atoms. R ₁ represents a substituent. m1 represents an integer from 0 to 4. If m1 is 2 or more, R ₁ may be a different substituents be the same substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents an integer of 2 to 6. The plurality of D _1s may be the same or different. ] The transparent electrode according to claim 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (2).

[In the general formula (2), X represents NR ₁₂ , an oxygen atom or a sulfur atom. R ₁₂ represents a hydrogen atom or a substituent. E _{11 to} E ₁₈ represent carbon atoms or nitrogen atoms, of which at least two represent carbon atoms. m11 represents an integer from 0 to 6. R ₁₁ represents a substituent. If m11 is 2 or more, R ₁₁ may be different even in the same. D ₁₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n11 represents an integer of 2-8. The plurality of D _11s may be the same or different. ] The transparent electrode according to claim 1, wherein the aromatic heterocyclic compound is a compound having a structure represented by the following general formula (3).

[In the general formula (3), E _{21 to} E ₃₀ represent a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. R ₂₁ represents a substituent. m21 represents an integer from 0 to 8. If m11 is 2 or _{more, R 21} may be the same or different. D ₂₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n21 represents an integer of 2 to 10. The plurality of D _11s may be the same or different. ] The transparent electrode according to claim 1 to 4, wherein the hetero atom is a nitrogen atom, an oxygen atom, or a sulfur atom. The transparent electrode according to claim 1 to 5, wherein the aromatic heterocyclic group is a five-membered ring. An electronic device comprising the transparent electrode according to any one of claims 1 to 6. An organic electroluminescence device comprising the transparent electrode according to any one of claims 1 to 6.

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