JP2014211964A - Transparent electrode, electronic device and organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent electrode having both sufficient conductivity and light permeability, and also having excellent durability, and an electronic device and an organic electroluminescent element which include the transparent electrode.SOLUTION: A transparent electrode 1 of the present invention includes a conductive layer 1b, and an intermediate layer 1a provided to be adjacent to the conductive layer 1b. The conductive layer 1b contains silver as a main component, and the intermediate layer 1a contains an aromatic heterocyclic compound which has two or more aromatic heterocyclic groups in the molecule, each aromatic heterocyclic group having three or more heteroatoms.

Description

  The present invention relates to a transparent electrode, an electronic device, and an organic electroluminescence element, and more particularly to a transparent electrode that has both conductivity and light transmittance and excellent durability, and an electronic device and an organic electroluminescence element using the transparent electrode. .

  An organic EL element (also referred to as an organic electroluminescent element) using electroluminescence of an organic material (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 V. It is a complete solid-state device and has many excellent features such as high brightness, high luminous efficiency, thinness, and light weight. For this reason, it has been attracting attention in recent years as surface light emitters such as backlights for various displays, display boards such as signboards and emergency lights, and illumination light sources.

  Such an organic EL element has a configuration in which a light emitting layer made of an organic material is disposed between two electrodes, and emitted light generated in the light emitting layer passes through the electrode and is extracted outside. For this reason, at least one of the two electrodes is configured as a transparent electrode.

As the transparent electrode, an oxide semiconductor material such as indium tin oxide (SnO ₂ -In ₂ O ₃ : Indium Tin Oxide: ITO) is generally used. Studies aiming at resistance have also been made (for example, see Patent Documents 1 and 2). However, since ITO uses rare metal indium, the material cost is high, and it is necessary to anneal at about 300 ° C. after film formation in order to reduce resistance.

Then, the technique (for example, refer patent document 3) which aimed at coexistence of the transmittance | permeability and electroconductivity by comprising a thin film using the alloy of silver (Ag) and magnesium (Mg) with high electrical conductivity, Short-wavelength region by forming a thin film using a technique of forming a thin film using zinc (Zn) or tin (Sn), which are inexpensive and easily available, as an raw material (see, for example, Patent Document 4), and an alloy of silver and aluminum. A technique (for example, refer to Patent Document 5) that transmits the light is proposed.
However, the resistance value of the electrode disclosed in Patent Document 3 is at most about 100Ω / □, which is insufficient as the conductivity of the electrode. In addition, since magnesium is easily oxidized, 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. In addition, ZnO-based thin films containing Zn are likely to react with water and change their performance, and SnO ₂ -based thin films containing Sn are difficult to etch.
The resistance value immediately after the production of the electrode disclosed in Patent Document 5 is 128Ω / □ at most, and it cannot be said that the electrode is a transparent electrode having both sufficient conductivity and light transmittance.

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

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

  The present invention has been made in view of the above-mentioned problems and circumstances, and the solution to the problem is a transparent electrode having sufficient conductivity and light transmittance and excellent in durability, an electronic device including the transparent electrode, and An organic electroluminescence device is provided.

  As a result of studying the cause of the above-mentioned problem in order to solve the above-mentioned problems, the inventor is a transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer, the conductive electrode The layer contains silver as a main component, and the intermediate layer contains an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms. And the light transmittance can be realized, and excellent durability can be realized, and the present invention has been achieved.

  That is, the said subject which concerns on this invention is solved by the following means.

1. A transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer,
The conductive layer contains silver as a main component,
The said intermediate | middle layer contains the aromatic heterocyclic compound which has 2 or more of aromatic heterocyclic groups which have 3 or more hetero atoms in a molecule | numerator, The transparent electrode characterized by the above-mentioned.

〔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 [Formula _(1), E 1 ~E ₆ represents a carbon atom or a nitrogen atom, of which at least two represents a carbon atom. R ₁ represents a substituent. m1 represents an integer of 0 to 4. When m1 is 2 or more, R ₁ may be the same or different substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents the integer of 2-6. The plurality of D ₁ 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. 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 (2).

[In 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 a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. m11 represents an integer of 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 to 8. The plurality of D ₁₁ 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). 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 (3).

In [Formula _{(3), E} 21 ~E ₃₀ represents a carbon atom or a nitrogen atom, of which at least two represents a carbon atom. R ₂₁ represents a substituent. m21 represents an integer of 0 to 8. When 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 ₁₁ may be the same or different. ]

  5. The transparent electrode according to any one of Items 1 to 4, wherein the heteroatom is a nitrogen atom, an oxygen atom, or a sulfur atom.

  6). The transparent electrode according to any one of Items 1 to 5, 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 in durability, an electronic device provided with the transparent electrode, and an organic electroluminescence element.

  Although the expression mechanism and action mechanism of the effect of the present invention are not clarified, it is presumed as follows.

That is, the transparent electrode of the present invention is provided with an electrically conductive layer composed mainly of silver on the intermediate layer, and the intermediate layer has an aromatic heterocyclic group having 3 or more heteroatoms. The structure is that an aromatic heterocyclic compound having 2 or more in the molecule is contained.
Accordingly, when forming a conductive layer on the upper part of the intermediate layer, an aromatic heterocyclic group having 3 or more heteroatoms in which the silver atoms constituting the conductive layer are contained in the intermediate layer is contained in the molecule. By interacting with the aromatic heterocyclic compound having at least one, the diffusion distance of silver atoms on the surface of the intermediate layer is reduced, and the aggregation of silver at specific locations can 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 a two-dimensional single crystal layer is formed around it. The film is formed by the layer growth type (Frank-van der Merwe: FM type) film growth.

In general, silver atoms attached on the surface of the intermediate layer are bonded while diffusing on the surface to form three-dimensional nuclei and grow into three-dimensional islands (Volume- It is considered that the film is easily formed into an island shape by the film growth using the Weber (VW type).
However, in the present invention, the island-like growth is achieved by the aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule, which is a silver affinity compound contained in the intermediate layer. Is suppressed, and it is assumed that layer growth is promoted.
Accordingly, it is possible to obtain a conductive layer having a uniform thickness even though the layer thickness is thin. 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 that can suppress aggregation of silver.

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

The transparent electrode of the present invention is a transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer,
The conductive layer contains silver as a main component,
The intermediate layer contains an aromatic heterocyclic compound having two or more aromatic heterocyclic groups having 3 or more heteroatoms in the molecule. This feature is a technical feature common to the inventions according to claims 1 to 8.

  As an embodiment of the present invention, it is preferable that the aromatic heterocyclic compound is a compound having a structure represented by the general formula (1) in view of affinity with silver and stability.

  Moreover, in this invention, it is preferable that the said aromatic heterocyclic compound is a compound which has a structure represented by the said General formula (2) from the point of affinity and stability with silver.

  Moreover, in this invention, it is preferable that the said aromatic heterocyclic compound is a compound which has a structure represented by the said General formula (3) from the point of affinity with silver and stability.

  Moreover, in this invention, it is preferable from a viewpoint of the effect expression of this invention that the said hetero atom is a nitrogen atom, an oxygen atom, or a sulfur atom.

  Moreover, in this invention, it is preferable from the viewpoint of the effect expression of this invention that the said aromatic heterocyclic group is a 5-membered ring.

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

  The transparent electrode of the present invention can be suitably included in an organic electroluminescence element. Thereby, it is possible to obtain an organic electroluminescence element having both sufficient conductivity and light transmittance and excellent durability.

Hereinafter, the present invention, its components, 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 value described before and behind that as a lower limit and an upper limit.

<< 1. Transparent electrode >>
<Configuration 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 stacked on the intermediate layer 1a. The conductive layer 1b is provided in this order. Among 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 refers to a component having the highest component 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 is preferably 60% by mass or more, more preferably 90% by mass or more, and 98% by mass or more. Particularly preferred.
Moreover, 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, the 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 and plastic. The substrate 11 may be transparent or opaque. When the transparent electrode 1 of the present invention is used in 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, and alkali-free glass. From the viewpoints 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, or from an inorganic or organic material. Or a hybrid film obtained by combining these films 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, cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones, Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Is mentioned.

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

  The material for forming the barrier film as described above may be any material that has a function of suppressing intrusion of factors that cause deterioration of electronic devices such as moisture and oxygen and organic EL elements. Silicon, silicon nitride, or the like can be used. Furthermore, in order to improve the brittleness of the barrier film, it is more preferable to have a laminated structure of these inorganic layers and layers (organic layers) made of an organic material. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for producing the barrier film is not particularly limited. For example, the vacuum deposition method, the sputtering method, the reactive sputtering method, the molecular beam epitaxy method, the cluster ion beam method, the ion plating method, the plasma polymerization method, the atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an 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, an 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 using an aromatic heterocyclic compound having two or more aromatic heterocyclic groups containing 3 or more heteroatoms in the molecule.
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 ink jet method, a coating method, a dip method, a vapor deposition method ( Resistance heating, EB method, etc.), sputtering methods, methods using dry processes such as CVD methods, and the like. Of these, the vapor 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 of 0 to 4. When m1 is 2 or more, R ₁ may be the same or different substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents the integer of 2-6. The plurality of D ₁ may be the same or different.

In the general formula (1), examples of the substituent represented by R ₁ include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group). 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 called aromatic carbocyclic groups, aryl groups, etc.), for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group Group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl Group), aromatic heterocyclic group (for example, furyl 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) , A diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), a phthalazinyl group, etc.), a heterocyclic group (eg, pyrrolidyl group, imidazolidyl group) , Morpholyl 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) Group, cyclohexyloxy group, etc.) An aryloxy group (for example, phenoxy group, naphthyloxy group, etc.), an alkylthio group (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (for example, cyclopentyl group) Thio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxy group) Carbonyl group etc.), aryloxycarbonyl group (eg phenyloxycarbonyl group, naphthyloxycarbonyl group etc.), sulfamoyl group (eg aminosulfonyl group, methylaminosulfur group) Nyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.) An acyl group (for example, 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 (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dode Silcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexyl) Carbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, Pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylamino Sulfonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, Phenylureido group naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, Naphthylsulfinyl 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), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (for example, fluoromethyl group, trifluoromethyl group, pentafluoro) Ethyl group, pentaful Orophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (eg, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphate ester group (eg, dihexyl) Phosphoryl group, etc.), phosphite group (for example, diphenylphosphinyl group, etc.), 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 the following.

R ₃₁ , R ₃₂ , R ₃₃ and R ₃₄ represent a hydrogen atom or a substituent. The substituent is the same group as R ₁ described above. L represents a bond or a divalent linking group. As the linking group, for example, an alkylene group, a cycloalkylene group, an arylene group, a group containing a hetero atom (for example, a divalent group containing a chalcogen atom such as —O— or —S—, —N (R ₃₅ ) — group, 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.

  Moreover, it is also preferable that an aromatic heterocyclic compound is a compound which has a structure represented by 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 a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. m11 represents an integer of 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 to 8. The plurality of D ₁₁ 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 ring formed by E _{11 to} E ₁₈ is preferably the following.

  Moreover, it is also preferable that an aromatic heterocyclic compound is a compound which has a structure represented by 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 of 0 to 8. When 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 ₁₁ may be the same or different.

In the general formula (3), examples of the substituent represented by R ₂₁ include those similar to the substituent 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, 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 .

In general formula (2) substituents provided in _{(D 11} and _{R 11)} need _only comprise one of the rings is formed by ring or _E 15 _{to E 18} are formed by _E 11 _{~ 14} Represents that. That is, for example, only the ring formed by E ₁₁ to ₁₄ may have a plurality of substituents, and either the ring formed by E ₁₁ to ₁₄ or the ring formed by E _{15 to} E ₁₈ It can also have a substituent. The same applies to the general formula (3).

[Specific examples of compounds contained in 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.
Although the specific example of the aromatic heterocyclic compound contained in the intermediate | middle layer 1a of this invention is shown below, it is not limited to these.

  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. for 24 hours under a nitrogen stream. The reaction solution was filtered to remove insolubles, THF was added, and the mixture was washed with saturated brine. The solvent was removed by distillation under reduced pressure, and the resulting 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 desired product. It was.

Synthesis Example 2 (Synthesis of I-29)
Diiododibenzothiophene 4.36g, mercaptophenyltetrazole 4.45g, cuprous oxide 1.10g, dipivaloylmethane 1.00g, potassium phosphate 4.36g, DMSO 50ml under nitrogen flow at 160 ° C for 24 hours Stir with heating. The reaction solution was filtered to remove insolubles, THF was added, and the mixture was washed with saturated brine. The solvent was removed by distillation under reduced pressure, and the resulting crude crystals were purified by column chromatography (SiO ₂ , developing solution THF / toluene) to obtain 3.00 g of the desired product (yield 56.0%, pale yellow crystals). 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, dipivaloylmethane 1.00 g, potassium phosphate 4.36 g, 50 ml of DMSO was heated and stirred at 160 ° C. for 24 hours under a nitrogen stream. The reaction solution was filtered to remove insolubles, THF was added, and the mixture was washed with saturated brine. The solvent was removed by distillation under reduced pressure, and the resulting crude crystals were purified by column chromatography (SiO ₂ , developing solution THF / toluene) to obtain 2.43 g of the desired product (yield 48.0%, pale yellow crystals). It was.

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

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

  The conductive layer 1b as described above may have a configuration in which a layer composed mainly of silver is divided into a plurality of layers as necessary.

Furthermore, 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 reflection component of the layer is reduced, and the transmittance of the transparent electrode is improved, which is more preferable. Moreover, it is preferable that the layer thickness is thicker than 5 nm because the conductivity of the layer becomes sufficient.

  In addition, in the transparent electrode 1 having a laminated structure including the intermediate layer 1a and the conductive layer 1b formed thereon, 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 transmittance so that the light transmittance of the transparent electrode 1 is not impaired. Moreover, it is good also as a structure which provided the layer as needed also under the intermediate | middle layer 1a, ie, between the intermediate | middle layer 1a and the board | substrate 11. FIG.

<Effect of transparent electrode>
The transparent electrode 1 having the above-described configuration has silver as a main component on the intermediate layer 1a containing an aromatic heterocyclic compound having two or more aromatic heterocyclic groups in the molecule having three or more heteroatoms. A conductive layer 1b is provided. As a result, when the conductive layer 1b is formed on 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 silver atoms The diffusion distance on the surface of 1a is reduced, and aggregation of silver is suppressed.

Here, in general, in the formation of a conductive layer containing silver as a main component, an island-shaped growth type (Volume-Weber: VW type) thin film grows, so that silver particles are easily isolated in an island shape, When the layer thickness (film thickness) is small, 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 ensure conductivity. However, if the film thickness is increased, the light transmittance is lowered, which is not suitable as a transparent electrode.

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

  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. However, each of the above materials used as the intermediate layer 1a has silver as a main component. Compared with the conductive layer 1b, a film having sufficiently good light transmittance is formed. On the other hand, the conductivity of the transparent electrode 1 is ensured mainly by the conductive layer 1b. Therefore, as described above, the conductive layer 1b composed mainly of silver has a thinner layer to ensure conductivity, thereby improving the conductivity of the transparent electrode 1 and the light transmittance. It is possible to achieve a balance with improvement of the above.

≪2. Applications of transparent electrodes >>
The transparent electrode 1 having the above-described configuration can be used for various electronic devices. Examples of electronic devices include organic EL elements, LEDs (Light Emitting Diodes), liquid crystal elements, solar cells, touch panels, etc. As electrode members that require light transmission in these electronic devices, the above-mentioned transparent The electrode 1 can be used.
Below, embodiment of the organic EL element using the transparent electrode 1 of this invention is described as an example of a use.

≪3. First example of organic EL element >>
<Configuration of organic EL element>
FIG. 2 is a schematic cross-sectional view showing a first example of an organic EL element using the transparent electrode 1 described above as an example of the electronic device of the present invention.
Below, the structure of an organic EL element is demonstrated based on this figure.

  As shown in FIG. 2, the organic EL element 100 is provided on a transparent substrate (substrate) 13, and in order from the transparent substrate 13 side, the light emitting functional layer 3 configured using the transparent electrode 1, an organic material, The counter electrode 5a is 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. For this reason, the organic EL element 100 is configured to extract 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 example 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 a hole injection layer 3a / a hole transport layer 3b / a light emitting layer 3c / an electron transport layer 3d / an electron injection layer 3e are stacked in this order from the transparent electrode 1 side that is an anode. Although illustrated, it is essential to have at least the light emitting layer 3c composed of an organic material. The hole injection layer 3a and the hole transport layer 3b may be provided as a hole transport injection layer. The electron transport layer 3d and the electron injection layer 3e may be provided as an electron transport injection layer. Of these light emitting functional layers 3, for example, the electron injection layer 3e may be made of an inorganic material.

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

  In the layer configuration as described above, the auxiliary electrode 15 may be provided in contact with the conductive layer 1 b 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 with a sealing material 17 described later on the transparent substrate 13 for the purpose of preventing deterioration of the light emitting functional layer 3 formed using an organic material or the like. ing. The sealing material 17 is fixed to the transparent substrate 13 side with an adhesive 19. However, the terminal portions of the transparent electrode 1 and the counter electrode 5a are provided on the transparent substrate 13 so as to be exposed from the sealing material 17 while being insulated from each other by the light emitting functional layer 3.

  Hereinafter, the details of the main layers for constituting the organic EL element 100 described above will be described in terms of 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 layers 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 substrate]
The transparent substrate 13 is the substrate 11 on which the transparent electrode 1 of the present invention described above is provided, and the transparent substrate 11 having light transmittance among the substrates 11 described above 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 sequentially formed from the transparent substrate 13 side. Here, in particular, the transparent electrode 1 functions as an anode, and the conductive layer 1b is a substantial anode.

[Counter electrode (cathode)]
The counter electrode 5a is an electrode film that functions as a cathode for supplying electrons to the light emitting functional layer 3, and is made of a metal, an alloy, an organic or inorganic conductive compound, or a mixture thereof. Specifically, aluminum, silver, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, indium, lithium / aluminum mixture, rare earth metal, ITO, ZnO, TiO ₂ , An oxide semiconductor such as SnO ₂ can be given.

  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 as 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.

  In addition, when this organic EL element 100 takes out the emitted light h also from the counter electrode 5a side, the counter electrode is made of a conductive material having a good light transmission property selected from the above-described conductive materials. 5a should just be comprised.

[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 preferred.

  The light emitting layer 3c is a layer that emits light by recombination of electrons injected from the electrode or the electron transport layer 3d and holes injected from the hole transport layer 3b, and the light emitting portion is the light emitting layer 3c. Even within the layer, it may be the interface between the light emitting layer 3c and the adjacent layer.

  There is no restriction | limiting in particular in the structure as such a light emitting layer 3c, if the light emitting material contained satisfies the light emission requirements. Moreover, 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-light emitting auxiliary layer (not shown) between the light emitting layers 3c.

  The total 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. In addition, the sum total of the layer thickness of the light emitting layer 3c is a layer thickness also including the said auxiliary layer, when a nonluminous auxiliary layer exists between the light emitting layers 3c.

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

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

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

  As a structure of the light emitting layer 3c, it is preferable to contain a host compound (light emitting host) and a light emitting material (light emitting dopant compound) and to emit light from the light emitting material.

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

  As a host compound, a well-known host compound may be used independently, or multiple types may be used. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. In addition, by using a plurality of kinds of light emitting materials described later, it is possible to mix different light emission, thereby obtaining an arbitrary light emission color.

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

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

  Although the specific example (H1-H79) of the host compound which can be used by this invention below is shown, it is not limited to these. Note that 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.

  As specific examples of known host compounds, compounds described in the following documents may be used. For example, Japanese Patent Application Laid-Open Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860 Gazette, 2002-334787 gazette, 2002-15871 gazette, 2002-334788 gazette, 2002-43056 gazette, 2002-334789 gazette, 2002-75645 gazette, 2002-338579 gazette. No. 2002-105445, No. 2002-343568, No. 2002-141173, No. 2002-352957, No. 2002-203683, No. 2002-363227, No. 2002-231453. No. 2003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060. 2002-302516, 2002-305083, 2002-305084, 2002-308837, and the like.

(Luminescent material)
(1) Phosphorescent compound As the luminescent material that can be used in the present invention, a phosphorescent compound is exemplified.

  A phosphorescent compound is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. A preferred phosphorescence quantum yield is 0.1 or more, although it is defined as 0.01 or more compounds.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, when the phosphorescent compound is used in the present invention, the above phosphorescence quantum yield (0.01 or more) is obtained in any solvent. It only has to be achieved.

There are two types of light emission principles of the phosphorescent compound.
One is that recombination of carriers occurs on the host compound to which carriers are 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. Energy transfer type.
The other is a carrier trap type in which the phosphorescent compound becomes a carrier trap, and recombination of carriers occurs on the phosphorescent compound, and light emission from the phosphorescent compound is obtained. In either case, the condition is that the excited state energy of the phosphorescent compound is 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 device, but preferably contains a group 8-10 metal in the periodic table of elements. More preferred are iridium complexes, osmium complexes, platinum complexes, and rare earth complexes, and most preferred are iridium complexes.

  In the present invention, at least one light emitting layer 3c may contain two or more 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 have changed.

  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 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).

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

In general formula (A), P and Q each represent a carbon atom or a nitrogen atom, and A ₁ represents an atomic group that forms an aromatic hydrocarbon ring or an aromatic heterocycle together with P—C. A ₂ represents an atomic group that forms an aromatic heterocycle with QN. P ₁ -L ₁ -P ₂ represents a bidentate ligand, and P ₁ and P ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L ₁ represents an atomic group that forms a bidentate ligand together with P ₁ and P ₂ . j1 represents an integer of 1 to 3, j2 represents an integer of 0 to 2, and j1 + j2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table.

In the general formula (A), the aromatic hydrocarbon ring formed by A ₁ together with P—C includes benzene ring, biphenyl ring, naphthalene ring, azulene ring, anthracene ring, phenanthrene ring, pyrene ring, chrysene ring, naphthacene ring , Triphenylene ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphthene ring, coronene ring, fluorene ring, fluoranthrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphen ring, picene ring , Pyrene ring, pyranthrene ring, anthraanthrene ring and the like.
These rings may further have a substituent represented by R ₁ in the general formula (1).

In the general formula (A), the aromatic heterocycle formed by A ₁ together with P—C includes a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and 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 And a carbazole ring.
Here, the azacarbazole ring refers to one in which at least one carbon atom of the benzene ring constituting the carbazole ring is replaced with a nitrogen atom.
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 QN include an oxazole ring, an oxadiazole ring, an oxatriazole ring, an isoxazole ring, a tetrazole ring, a thiadiazole ring, a thiatriazole ring, Examples include isothiazole ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, imidazole ring, pyrazole ring, and 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, and picolinic acid.

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

In the general formula (A), M ₁ is a transition metal element of Group 8 to Group 10 (also referred to simply as a transition metal) in the periodic table, and iridium is particularly preferable.

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

In general formula (B), Z represents a hydrocarbon ring group or a heterocyclic group. P and Q each represent a carbon atom or a nitrogen atom, and A ₁ represents an atomic group that forms an aromatic hydrocarbon ring or an aromatic heterocyclic ring together with P—C. 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 each represents a hydrogen atom or a substituent. P ₁ -L ₁ -P ₂ represents a bidentate ligand, and P ₁ and P ₂ each independently represent a carbon atom, a nitrogen atom, or an oxygen atom. L ₁ represents an atomic group that forms a bidentate ligand together with P ₁ and P ₂ . j1 represents an integer of 1 to 3, j2 represents an integer of 0 to 2, and j1 + j2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table.

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 aromatic hydrocarbon group, aryl group, etc.) include, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl. Group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, 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 and an aromatic heterocyclic group. Examples of the non-aromatic heterocyclic group include an epoxy ring and an aziridine group. Ring, thiirane ring, oxetane ring, azetidine ring, thietane ring, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane 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, thiomorpholine Ring, thiomorpholine-1,1-dioxide And groups derived from a 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, triazolyl group (for example, 1,2,4-triazol-1-yl). Group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group , Benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), quinoxalinyl Group, pyridazinyl group, triazinyl group, key Zoriniru group, 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 ring formed by A ₁ together with P—C includes benzene ring, biphenyl ring, naphthalene ring, azulene ring, anthracene ring, phenanthrene ring, pyrene ring, chrysene ring, naphthacene. Ring, triphenylene ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphthene ring, coronene ring, fluorene ring, fluoranthrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphen ring, picene And a ring, a pyrene ring, a pyranthrene ring, and an anthraanthrene ring.
These groups may be unsubstituted or may have a substituent represented by R ₁ in the general formula (1).

In the general formula (B), the aromatic heterocycle formed by A ₁ together with P—C includes 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, carboline ring And azacarbazole ring.
Here, the azacarbazole ring refers to one in which at least one carbon atom of the benzene ring constituting the carbazole ring is replaced with a nitrogen atom.
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 )-, -C (R ₀₁ ) = N- represented by A ₃ in the general formula (B), R ₀₁ , R ₀₂ each has the same meaning as the substituent 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. Is mentioned.

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

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

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

In 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 combine with each other to form a ring. n03 represents an integer of 1 to 4. Z ₁ represents an atomic group necessary for forming a 6-membered aromatic hydrocarbon ring or a 5-membered or 6-membered aromatic heterocyclic ring together with C—C. Z ₂ represents an atomic group necessary for forming a hydrocarbon ring group or a heterocyclic group. P ₁ -L ₁ -P ₂ represents a bidentate ligand, and P ₁ and P ₂ each independently represent a carbon atom, a nitrogen atom or an oxygen atom. L ₁ represents an atomic group forming a bidentate ligand together with P ₁ and P ₂ . j1 represents an integer of 1 to 3, j2 represents an integer of 0 to 2, and j1 + j2 is 2 or 3. M ₁ represents a group 8-10 transition metal element in the periodic table. R ₀₃ and R ₀₆ , R ₀₄ and R _06, and R ₀₅ and R ₀₆ may be bonded to each other to form a ring.

In the general formula (C), each of the substituents represented by R ₀₃ , R ₀₄ , R ₀₅ , and R ₀₆ has the same meaning as the substituent represented by R ₁ in the general formula (1).

In the general formula (C), examples of the 6-membered aromatic hydrocarbon ring formed by Z ₁ together with C—C include a benzene ring.
These rings may further have a substituent, and examples of such a substituent include the same substituents represented by R ₁ in the general formula (1).

In the general formula (C), examples of the 5-membered or 6-membered aromatic heterocycle formed by Z ₁ together with C—C include an oxazole ring, an oxadiazole ring, an oxatriazole ring, an isoxazole ring, a tetrazole ring, Examples include thiadiazole ring, thiatriazole ring, isothiazole ring, thiophene ring, furan ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, imidazole ring, pyrazole ring, triazole ring and the like.
These rings may further have a substituent, and examples of such a substituent include the same substituents represented by R ₁ in the general formula (1).

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. Group, cyclopentyl group, cyclohexyl group and the like.
These groups may be unsubstituted or may have a substituent, and examples of such a substituent include the same substituents represented by R ₁ in the general formula (1). .

Examples of the aromatic hydrocarbon ring group (also referred to as aromatic hydrocarbon group, aryl group, etc.) include, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl. Group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group and the like.
These groups may be unsubstituted or may have a substituent, and examples of such a substituent include the same 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 and an aromatic heterocyclic group. Examples of the non-aromatic heterocyclic group include an epoxy ring, Aziridine ring, thiirane ring, oxetane ring, azetidine ring, thietane ring, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane 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 Morpholine ring, thiomorpholine-1,1-dioxy De ring, pyranose ring, a diazabicyclo [2,2,2] - and the groups derived from the octane ring.
These groups may be unsubstituted or may have a substituent, and examples of such a substituent include the same substituents 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, triazolyl group (for example, 1,2,4-triazol-1-yl). Group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group , Benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group , Pyridazinyl group, triazinyl group, quinazo Group, phthalazinyl group, and the like.
These rings may be unsubstituted or may have a substituent. Examples of such a substituent include the same substituents represented by R ₁ in the general formula (1).

In the general formula (C), the group formed by Z ₁ and Z ₂ is preferably a benzene ring.

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 Synonymous with rank.

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.

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

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

  The phosphorescent compound (also referred to as a phosphorescent metal complex or the like) is described in, for example, Organic Letter, vol. 16, 2579-2581 (2001), Inorganic Chemistry, Vol. 30, No. 8, 1685-1687 (1991), J. Am. Am. Chem. Soc. , 123, 4304 (2001), Inorganic Chemistry, Vol. 40, No. 7, 1704-1711 (2001), Inorganic Chemistry, Vol. 41, No. 12, 3055-3066 (2002) , New Journal of Chemistry. , Vol. 26, 1171 (2002), European Journal of Organic Chemistry, Vol. 4, pages 695-709 (2004), and synthesis by applying methods such as references described in these documents. it can.

(2) Fluorescent compounds Fluorescent compounds include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, Examples include perylene dyes, stilbene dyes, polythiophene dyes, and rare earth complex 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 lower the driving voltage and improve the light emission luminance. “The organic EL element and the forefront of its industrialization (November 30, 1998, NT. 2) Chapter 2 “Electrode Materials” (pages 123 to 166) of the 2nd volume of “S. Co., Ltd.”, which includes a hole injection layer 3a and an electron injection layer 3e.

  The injection layer can be provided as necessary. The hole injection layer 3a may be present between the anode and the light emitting layer 3c or the hole transport layer 3b, and the electron injection layer 3e 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 described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069, and the like. Specific examples thereof include phthalocyanine represented 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 described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like, and specifically represented 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 desirably 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 can be provided as a single layer or a plurality of layers.

  The hole transport material has any of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole 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 stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  Although the above-mentioned thing can be used as a positive hole transport material, It is preferable to use a porphyrin compound, an aromatic tertiary amine compound, and a styryl amine compound, especially an aromatic tertiary amine compound.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include 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 ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostilbenzene; N-phenylcarbazole and also two fused aromatic rings described in US Pat. No. 5,061,569 In the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-30868 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA) in which three triphenylamine units described in Japanese Patent Publication are linked in a starburst type ) And the like.

  Furthermore, 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. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. , Applied Physics Letters, 80 (2002), p. A so-called p-type hole transport material as described in 139 can also be used. In the present invention, it is preferable to use these materials because a light-emitting element 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 ink jet method, or an LB method. be able to. Although there is no restriction | limiting in particular about the layer thickness of the positive hole transport layer 3b, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The hole transport layer 3b may have a single layer structure composed of one or more of the above materials.

  Also, the p-type can be enhanced by doping impurities into the material of the hole transport layer 3b. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  Thus, it is preferable to increase the p property of the hole transport layer 3b because an element with 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, the electron injection layer 3e and the 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 structure.

  As an electron transport material (also serving as a hole blocking material) constituting the layer portion adjacent to the light emitting layer 3c in the electron transport layer 3d having a single layer structure and the electron transport layer 3d having a multilayer structure, electrons injected from the cathode are used. What is necessary is just to have the function to transmit to the light emitting layer 3c. As such a material, any one of conventionally known compounds can be selected and used. Examples include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane, anthrone derivatives, and oxadiazole derivatives. Further, in the above oxadiazole derivative, a thiadiazole derivative in which an oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group are also used as the material for the electron transport layer 3d. Can do. Furthermore, 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.

In addition, 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 Metal complexes replaced by 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 having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the material for the electron transport layer 3d. Further, a distyrylpyrazine derivative that is also used as a material for the light emitting layer 3c can be used as a material for the electron transport layer 3d. An inorganic semiconductor such as -SiC can also be used as the material of the electron transport layer 3d.

  The electron transport layer 3d can be formed by thinning the above material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the layer thickness of 3 d of electron carrying layers, Usually, 5 nm-about 5 micrometers, Preferably it is the range of 5-200 nm. The electron transport layer 3d may have a single layer structure composed of one or more of the above materials.

  In addition, 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, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like. Furthermore, 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 can be used. Thus, when the n property of the electron transport layer 3d is increased, an element with lower power consumption can be manufactured.

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

[Blocking layer: hole blocking layer, electron blocking layer]
The blocking layer is provided as necessary in addition to the basic constituent layer of the light emitting functional layer 3 described above. For example, it is described in JP-A Nos. 11-204258, 11-204359, and “Organic EL elements and their forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). There is a hole blocking (hole blocking) layer.

  The hole blocking layer has the 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 but has a very small ability to transport holes, and recombines electrons and holes by blocking holes while transporting electrons. Probability can be improved. Moreover, the structure of said electron carrying layer 3d can be used as a hole-blocking layer as needed. The hole blocking layer is preferably provided adjacent to the light emitting layer 3c.

  On the other hand, the electron blocking layer has the 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 but has a very small ability to transport electrons, and improves the probability of recombination of electrons and holes by blocking electrons while transporting holes. be able to. Moreover, the structure of said positive hole transport layer 3b can be used as an electron blocking layer as needed. The layer 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 reducing the resistance of the transparent electrode 1, and is provided in contact with the conductive layer 1 b of the transparent electrode 1. The material for forming the auxiliary electrode 15 is preferably a metal with low resistance such as gold, platinum, silver, copper, or aluminum. Since these metals have low light transmittance, a pattern is formed in a range not affected by extraction of the emitted light h from the light extraction surface 13a. Examples of a method for producing such an auxiliary electrode 15 include a vapor deposition method, a sputtering method, a printing method, an ink jet 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-like (film-like) sealing member that is fixed to the transparent substrate 13 side by the adhesive 19. It may be a stop 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 transparent electrode 1 of the organic EL element 100 and the terminal portions of the counter electrode 5a are electrically connected to this electrode.

  Specific examples of the plate-like (film-like) sealing material 17 include a glass substrate, a polymer substrate, a metal substrate, and the like. These substrate materials may be used in the form of a thin 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, and polysulfone. 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.

  Among them, since the element can be thinned, a thin film-like polymer substrate or metal substrate can be preferably used as the sealing material.

Further, the polymer substrate in the form of a film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / m ² · 24 h · atm or less, according to JIS K 7129-1992. The water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured by the above method is preferably 1 × 10 ⁻³ g / m ² · 24 h or less.

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

An adhesive 19 for fixing such a plate-shaped sealing material 17 to the transparent substrate 13 side seals the organic EL element 100 sandwiched between the sealing material 17 and the transparent substrate 13. Used as a sealing agent. Specifically, such an adhesive 19 is a photocuring and thermosetting adhesive having a reactive vinyl group of an acrylic acid-based oligomer, a methacrylic acid-based oligomer, a moisture-curing type such as 2-cyanoacrylic acid ester, or the like. Can be mentioned.
In addition, epoxy-based heat and chemical curing type (two-component mixing), hot-melt type polyamide, polyester, polyolefin, and cationic curing type UV-curable epoxy resin adhesive can also be exemplified.

  In addition, the organic material which comprises the organic EL element 100 may deteriorate with heat processing. For this reason, the adhesive 19 is preferably one that can be adhesively cured from room temperature to 80 ° C. Further, a desiccant may be dispersed in the adhesive 19.

  Application | coating of the adhesive agent 19 to the adhesion part of the sealing material 17 and the transparent substrate 13 may use a commercially available dispenser, and may print like screen printing.

  In addition, when a gap is formed between the plate-shaped sealing material 17, the transparent substrate 13, and the adhesive 19, in this gap, in the gas phase and the liquid phase, an inert gas such as nitrogen or argon or a fluorine is used. It is preferable to inject an inert liquid such as activated hydrocarbon or silicon oil. A vacuum can also be used. Moreover, a hygroscopic compound can also 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) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

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

  Such a sealing film is configured using an inorganic material or an organic material. In particular, it is made of a material having a function of suppressing intrusion of a substance that causes deterioration of the light emitting functional layer 3 in the organic EL element 100 such as moisture and oxygen. As such a material, for example, inorganic materials such as silicon oxide, silicon dioxide, and silicon nitride are used. Furthermore, in order to improve the brittleness of the sealing film, a laminated structure may be formed by using a film made of an organic material together with a film made of these inorganic materials.

  The method for producing these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or 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 in particular when the sealing material 17 is a sealing film, sufficient mechanical protection is provided for the organic EL element 100. 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, a polymer material film or a metal material film is applied. Among these, it is particularly preferable to use a polymer film because it is light and thin.

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

  First, an intermediate layer 1a made of an aromatic heterocyclic compound having two or more aromatic heterocyclic groups having 3 or more heteroatoms in the molecule is formed on the transparent substrate 13 at a layer of 1 μm or less, preferably 10 to 100 nm. It forms by appropriate methods, such as a vapor deposition method, so that it may become thick. Next, the conductive layer 1b made of silver (or an alloy containing silver) is formed on the intermediate layer 1a by an appropriate method such as vapor deposition so as to have a layer thickness in the range of 5 to 20 nm, preferably in the range of 5 to 12 nm. And forming a transparent electrode 1 to be an anode.

Next, a hole injection layer 3 a, a hole transport layer 3 b, a light emitting layer 3 c, an electron transport layer 3 d, and an electron injection layer 3 e are formed in this order to form the light emitting functional layer 3. The film formation of each of these layers includes spin coating, casting, ink jet, vapor deposition, and printing, but vacuum vapor deposition is easy because a homogeneous film is easily obtained and pinholes are difficult to generate. The method or spin coating method is particularly preferred. Further, different film formation methods may be applied for each layer. When employing a vapor deposition method for forming each of these layers, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 to 450 ° C. and a degree of vacuum of 1 × 10 ⁻⁶ to 1 × 10 ^−2. It is desirable to appropriately select each condition in the ranges of Pa, vapor deposition rate of 0.01 to 50 nm / second, substrate temperature of −50 to 300 ° C., and 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 thereon by an appropriate film forming method such as a vapor deposition method or a sputtering method. At this time, the counter electrode 5 a is patterned in a shape in which a terminal portion is drawn from the upper side of the light emitting functional layer 3 to the periphery of the transparent substrate 13 while maintaining the insulating state with respect to the transparent electrode 1 by the light emitting functional layer 3. Thereby, the organic EL element 100 is obtained. Thereafter, 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 is obtained on the transparent substrate 13. In the production of such an organic EL element 100, it is preferable to produce from the light emitting functional layer 3 to the counter electrode 5a consistently by a single evacuation. However, the transparent substrate 13 is taken out from the vacuum atmosphere in the middle to perform different formations. A film method may be applied. At that time, it is necessary to consider that the work is performed 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 an anode has a positive polarity, the counter electrode 5a as a cathode has a negative polarity, and a voltage of about 2 to 40V. Luminescence can be observed by applying. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

<Effect of organic EL element>
The organic EL element 100 described above has a configuration in which the transparent electrode 1 having both conductivity and light transmittance according to 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 thereon. is there. For this reason, the extraction efficiency of the emitted light h from the transparent electrode 1 side is improved while applying a sufficient voltage between the transparent electrode 1 and the counter electrode 5a to realize high luminance light emission in the organic EL element 100. Therefore, it is possible to increase the luminance. Further, it is possible to improve the light emission life by reducing the drive voltage for obtaining a predetermined luminance.
As will be described later, the intermediate layer 1a of the present invention may be provided in an anode or a cathode, or an electron transport layer 3d having electron injection properties may be provided as the intermediate layer 1a in the transparent electrode 1. In particular, it is preferable that the anode that does not participate in light emission includes the intermediate layer 1a in that the layer thickness can be appropriately changed.

<< 4. Second example of organic EL element >>
<Configuration of organic EL element>
FIG. 3 is a schematic cross-sectional view showing a second example of an organic EL element using the transparent electrode 1 described above as an example of the electronic device of the present invention. The organic EL element 200 of the second example shown in FIG. 3 is different from the organic EL element 100 of the first example shown in FIG. 2 in that the transparent electrode 1 is used as a cathode. Hereinafter, a detailed description of the same components as those in the first example will be omitted, and a 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 the transparent electrode 1 of the present invention described above is used as the transparent electrode 1 on the transparent substrate 13 as in the first example. ing. For this reason, the organic EL element 200 is configured to extract the emitted light h from at least the transparent substrate 13 side. However, the transparent electrode 1 is used as a cathode (cathode). For this reason, the counter electrode 5b is used as an anode.

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

  As an example of the second example, an 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 functioning as a cathode. The configuration is exemplified. However, it is essential to have at least the 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 in the same manner as described in the first example. 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 5 b becomes the light emitting region in the organic EL element 200 as in the first example.

  In the layer configuration 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, or a mixture thereof. Specific examples 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 produced by forming a thin film of these conductive materials by a method such as vapor deposition or sputtering. Further, the sheet resistance value as 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.

  In addition, when this organic EL element 200 is comprised so that emitted light h can be taken out also from the counter electrode 5b side, as a material which comprises the counter electrode 5b, favorable light transmittance is mentioned among the electrically conductive materials mentioned above. A suitable conductive material is selected and used.

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

  Of the main layers constituting the organic EL element 200 described above, the detailed structure of the constituent elements other than the counter electrode 5b used as the anode and the method for manufacturing the organic EL element 200 are the same as in the first example. Therefore, detailed description is omitted.

<Effect of organic EL element>
The organic EL element 200 described above has a configuration in which the transparent electrode 1 having both conductivity and light transmittance according to the present invention is used as a cathode, and the light emitting functional layer 3 and the counter electrode 5b serving as an anode are provided on the transparent electrode 1. is there. For this reason, 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 light emitted from the transparent electrode 1 side. It is possible to increase the luminance by improving the extraction efficiency of h. Further, it is possible to improve the light emission life by reducing the drive voltage for obtaining a predetermined luminance.

≪5. Third example of organic EL element >>
<Configuration 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 organic EL element 300 of the third example shown in FIG. 4 is different from the organic EL element 100 of the first example shown in FIG. 2 in that a counter electrode 5c is provided on the substrate 131 side, and the light emitting functional layer 3 and It is in the place which laminated | stacked the transparent electrode 1 in this order. Hereinafter, the detailed description of the same components as those 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 a substrate 131, and the counter electrode 5c serving as an anode, the light emitting functional layer 3, and the transparent electrode 1 serving as a cathode are laminated in this order from the substrate 131 side. . Among these, the transparent electrode 1 of the present invention described above is used as the transparent electrode 1. For this reason, the organic EL element 300 is configured to extract the emitted light h from at least the transparent electrode 1 side opposite to the substrate 131.

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

  An example of the case of the third example is 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 stacked in this order on the counter electrode 5c functioning as an anode. The However, it is essential to have at least the light emitting layer 3c configured using an organic material. The electron transport layer 3d also serves as the electron injection layer 3e, and is provided as an electron transport layer 3d having electron injection properties.

  In particular, the characteristic structure of the organic EL element 300 of the third example is that an electron transport layer 3 d having electron injection properties is provided as the intermediate layer 1 a 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 also serving as an electron transport layer 3d having electron injection properties, and a conductive layer 1b provided on the intermediate layer 1a. It is.

  Such an electron transport layer 3d is configured 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 necessary, as described in the first example. However, the electron transport also serving as the intermediate layer 1a of the transparent electrode 1 is used. 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 configuration as described above, 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, as in the first example.

  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 same as in the example.

Furthermore, the counter electrode 5c used as the anode is composed of a metal, an alloy, an organic or inorganic conductive compound, or a mixture thereof. Specific examples 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 produced by forming a thin film of these conductive materials by a method such as vapor deposition or sputtering. Further, the sheet resistance value as 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.

  In addition, when this organic EL element 300 is comprised so that the emitted light h can be taken out also from the counter electrode 5c side, as a material which comprises the counter electrode 5c, light transmittance is favorable among the electrically conductive materials mentioned above. A suitable conductive material is selected and used. In this case, the substrate 131 is the same as the transparent substrate 13 described in the first example.

  The organic EL element 300 having the above configuration is sealed with the sealing material 17 in the same manner 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 opposite to the organic EL element 300 in a portion substantially parallel to the substrate 131 of the sealing material 17 is used as the light extraction surface 17a.

<Effect of organic EL element>
In the organic EL element 300 described above, the electron transporting layer 3d having the electron injecting property constituting the uppermost part of the light emitting functional layer 3 is used as the intermediate layer 1a, and the conductive layer 1b is provided on the upper layer, thereby providing the intermediate layer 1a and The transparent electrode 1 composed of the upper conductive layer 1b is provided as a cathode. Therefore, similarly to the first example and the second example, 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, while the transparent electrode 1 side. It is possible to increase the luminance by improving the extraction efficiency of the emitted light h from the light source. Further, it is possible to improve the light emission life by reducing the drive voltage for obtaining a predetermined luminance. Further, when the counter electrode 5c is light transmissive, the emitted light h can be extracted from the counter electrode 5c.

  In the third example described above, the intermediate layer 1a of the transparent electrode 1 has been described as also serving as the electron transport layer 3d having electron injection properties. However, the present example is not limited to this, and the intermediate layer 1a may also serve as an electron transport layer 3d that does not have electron injection properties, or the intermediate layer 1a may serve as an electron injection layer instead of an electron transport layer. In addition, the intermediate layer 1a may be formed as an extremely thin film that does not affect the light emitting function of the organic EL element. In this case, the intermediate layer 1a has electron transport properties and electron injection properties. Not.

  Further, when the intermediate layer 1a of the transparent electrode 1 is formed as an extremely thin 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, and the light emitting functional layer 3 The transparent electrode 1 may be an anode. In this case, the light emitting functional layer 3 is, for example, 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 stacked. A transparent electrode 1 having a laminated structure of an extremely thin intermediate layer 1a and a conductive layer 1b is provided as an anode on the top.

≪6. Applications of organic EL elements >>
Since the organic EL elements having the above-described configurations are surface light emitters as described above, they can be used as various light emission sources. For example, lighting devices such as home lighting and interior lighting, backlights for watches and liquid crystals, lighting for billboard advertisements, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, Examples include a light source of an optical sensor. In particular, it can be effectively used for a backlight of a liquid crystal display device combined with a color filter and a light source for illumination.

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

  The driving method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. In addition, a color or full-color display device can be manufactured by using two or more organic EL elements of the present invention having different emission colors.

  Hereinafter, a lighting device will be described as an example of the application, and then a lighting device in which the light emitting surface is enlarged by tiling will be described.

<< 6-1. Lighting device-1 >>
The illumination device can include the organic EL element of the present invention.

  The organic EL element used in the lighting device may be designed such 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, etc. It is not limited to. Moreover, you may use for the said use by making a laser oscillation.

  In addition, the material used for the organic EL element of this invention is applicable to the organic EL element (white organic EL element) which produces substantially white light emission. For example, a plurality of luminescent colors can be simultaneously emitted by a plurality of luminescent materials, and white light emission can be obtained by mixing colors. As a combination of a plurality of emission colors, those containing the three emission maximum wavelengths of the three primary colors of red, green and blue may be used, or two emission using the complementary colors such as blue and yellow, blue green and orange, etc. It may contain a maximum wavelength.

  In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and excitation of light from the light emitting materials. Any combination with a pigment material that emits light as light may be used, but in a white organic EL element, a combination of a plurality of light-emitting dopants may be used.

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

  Moreover, there is no restriction | limiting in particular as a light emitting material used for the light emitting layer of such a white organic EL element, For example, if it is a backlight in a liquid crystal display element, it will adapt to the wavelength range corresponding to CF (color filter) characteristic. In addition, any one of the above metal complexes and known light emitting materials may be selected and combined to be whitened.

  If the white organic EL element demonstrated above is used, it is possible to produce the illuminating device which produces substantially white light emission.

≪6-2. Lighting device-2 >>
FIG. 5 is a schematic cross-sectional view of an illuminating device having a large light emitting surface using a plurality of organic EL elements having the above-described configurations.
As shown in FIG. 5, the illuminating device 21 has a light emitting surface having a large area by arranging a plurality of light emitting panels 22 including the organic EL elements 100 on the transparent substrate 13 on the support substrate 23 (tiling). This is a structured. The support substrate 23 may also serve as the 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. In addition, the edge part of the transparent electrode 1 which is an anode, and the counter electrode 5a which is a cathode are exposed around the light emission panel 22. FIG. However, only the exposed part of the counter electrode 5a is shown in FIG.
In FIG. 5, as the light emitting functional layer 3 constituting the organic EL element 100, the hole injection layer 3a / the hole transport layer 3b / the light emitting layer 3c / the electron transport layer 3d / the electron injection layer 3e are formed on the transparent electrode 1. A configuration in which the layers are sequentially stacked is shown as an example.

  In the lighting device 21 having such a configuration, the center of each light emitting panel 22 is a light emitting area A, and a non-light emitting area B is generated between the light emitting panels 22. For this reason, a light extraction member for increasing the light extraction amount 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 collecting sheet or a light diffusion sheet can be used.

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

[Example 1]
<< Preparation of transparent electrode >>
As will be described below, the transparent electrodes 1-1 to 1-19 were fabricated so that the area of the conductive region was 5 cm × 5 cm. The transparent electrodes 1-1 to 1-4 are produced as a single-layer transparent electrode composed of only a conductive layer, and the transparent electrodes 1-5 to 1-19 are transparent in a laminated structure of an intermediate layer and a conductive layer. It produced as an electrode.

(1) Production of transparent electrode 1-1 First, a transparent non-alkali glass substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus and attached to a vacuum chamber of the vacuum deposition apparatus. Moreover, silver (Ag) was filled in the resistance heating board made from tungsten, and it attached in the said vacuum chamber. Next, after reducing 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 range of the deposition rate of 0.1 to 0.2 nm / second. A conductive layer made of silver was formed to produce a transparent electrode 1-1 having a single layer structure.

(2) Preparation of transparent electrodes 1-2 to 1-4 Transparent electrode 1-2 was prepared in the same manner except that the thickness of the conductive layer was changed to 8 nm, 10 nm, and 15 nm, respectively. ˜1-4 were prepared.

(3) Production of transparent electrode 1-5 A transparent non-alkali glass substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, and the compound I-47 of the present invention was filled in a resistance heating board made of tantalum. The substrate holder and the heating board were attached to the 1st vacuum chamber of a vacuum evaporation system. Moreover, silver was filled in the resistance heating board made from tungsten, and it attached in the 2nd vacuum chamber.

In this state, first, the first vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa, and then heated by energizing the heating board containing Compound I-47, with a deposition rate of 0.1 to 0.2 nm / second. 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 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 the heating board containing silver was energized and heated, A conductive layer made of silver having a layer thickness of 5 nm was formed within a range of the deposition rate of 0.1 to 0.2 nm / second, and a transparent electrode 1-5 having a laminated structure of an intermediate layer and a conductive layer was produced. .

(4) Production of transparent electrodes 1-6 to 1-8 In production of the transparent electrode 5, the transparent electrodes 1-6 to 1 were prepared in the same manner except that the thickness of the conductive layer was changed to 8 nm, 10 nm, and 15 nm, respectively. -8 was produced.

(5) Production of transparent electrodes 1-9 to 1-16 In production of transparent electrode 1-6, transparent electrode 1-9 was similarly produced except that the constituent materials of the intermediate layer were changed to the compounds shown in Table 1, respectively. ˜1-16 were produced.

(6) Preparation of transparent electrodes 1-17 to 1-19 In the preparation of transparent electrodes 1-17 to 1-19, the transparent electrode was changed in the same manner except that the substrate was changed from non-alkali glass to a PET (polyethylene terephthalate) film. 1-17 to 1-19 were produced.

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

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

(2) Measurement of sheet resistance value About each produced transparent electrode, sheet resistance value (ohm / square) was measured by the 4-probe method constant current application system using the resistivity meter (MCP-T610 by Mitsubishi Chemical Corporation).
The measurement results are shown in Table 1.

(3) Measurement of electrode life under a constant current A constant current of 10 A is continuously supplied to each transparent electrode produced under the atmosphere, and the time required for the sheet resistance value to be double the initial value is measured. did.
The measurement results are shown in Table 1.
The electrode life is shown as a relative value where the electrode life of the transparent electrode 1-4 is 100.

(4) Summary As is clear from Table 1, the transparent electrodes 1-5 to 1-19 of the present invention in which a conductive layer mainly composed of silver (Ag) is provided on the 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 examples all have low light transmittance and high sheet resistance.
Moreover, also in durability (electrode lifetime), it turns out that the transparent electrodes 1-5 to 1-19 of this invention are excellent compared with the transparent electrodes 1-1 to 1-4 of a comparative example.

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

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

(1) Production of light-emitting panel 2-1 First, the transparent substrate 13 produced in Example 1 on which the transparent electrode 1 having only the conductive layer 1b was formed was fixed to a substrate holder of a commercially available vacuum deposition apparatus. A vapor deposition mask was disposed opposite to the formation surface side of the transparent electrode 1. 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 forming each layer. In addition, the heating board used what was produced with the resistance heating material made from tungsten.

Next, the inside of the vapor deposition chamber of the vacuum vapor deposition apparatus was depressurized to a vacuum degree of 4 × 10 ⁻⁴ Pa, and each layer was formed as follows by sequentially energizing and heating the heating board containing each material.

  First, as a hole transport injection material, a heating board containing α-NPD represented by the following structural formula is energized and heated, and hole transport injection serving as both a hole injection layer and a hole transport layer made of α-NPD The layer 31 was formed on the conductive layer 1 b constituting the transparent electrode 1. At this time, the deposition rate was 0.1 to 0.2 nm / second, 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 energized independently to emit light composed of the host material H4 and the phosphorescent compound Ir-4. 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 deposition rate was 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 deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 10 nm.

  Thereafter, a heating board containing ET-4 represented by the following structural formula as an electron transporting material and a heating board containing potassium fluoride are energized independently to transport electrons consisting of ET-4 and potassium fluoride. Layer 3d was deposited on hole blocking layer 33. At this time, the energization of the heating board was adjusted so that the 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 deposition rate was 0.01 to 0.02 nm / second, and the layer thickness was 1 nm.

  Thereafter, 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 as a counter electrode material was attached while maintaining the vacuum state. . Next, in the processing chamber, a film was formed at a film forming rate of 0.3 to 0.5 nm / second, and a light-transmitting counter electrode 5a made of ITO having a layer thickness of 150 nm was formed as a cathode. Thus, the organic EL element 400 was formed on the transparent substrate 13.

  Thereafter, 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 interposed between the sealing material 17 and the transparent substrate 13 so as to surround the organic EL element 400. ). As the adhesive 19, an epoxy photocurable adhesive (Lux Track 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. Stopped.

  In forming the organic EL element 400, an evaporation mask is used for forming each layer, and the central 4.5 cm × 4.5 cm of the 5 cm × 5 cm transparent substrate 13 is defined as the light emitting region A, and the entire circumference of the light emitting region A is formed. A non-light emitting region B having a width of 0.25 cm was provided. Further, the transparent electrode 1 serving as the anode and the counter electrode 5a serving as the cathode are insulated by the light emitting functional layer 3 from the hole transport injection layer 31 to the electron injection layer 3e, and a terminal portion is provided on the periphery of the transparent substrate 13. Was formed in a drawn shape.

As described above, the organic EL element 400 was provided on the transparent substrate 13, and the light emitting panel 2-1 was sealed with the sealing material 17 and the adhesive 19.
In the light emitting panel 2-1, the emitted light h of each color generated in the light emitting layer 3c is extracted 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) Production of light-emitting panels 2-2 to 2-2-19 In the production of the light-emitting panels 2-1, except that the transparent electrodes shown in Table 2 were changed, the light-emitting panels 2-2 to 2-16 were formed in the same manner. Produced.
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 a PET (polyethylene terephthalate) film.

<Evaluation of luminous panel>
About the produced light emitting panels 2-1 to 2-19, according to the following method, the light transmittance, the drive voltage, and durability (luminance half life) were measured.

(1) Measurement of light transmittance About each produced light emission panel, the light transmittance (%) in wavelength 550nm is set using the spectrophotometer (U-3300 by Hitachi, Ltd.) and the board | substrate of the transparent electrode of each light emission panel as a reference. Was measured.
The measurement results are shown in Table 2.

(2) Measurement of drive voltage For each of the produced light-emitting panels, front luminance on 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) 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). For the measurement of luminance, a spectral radiance meter CS-1000 (manufactured by Konica Minolta) was used. It represents that it is so preferable that the numerical value of the obtained drive voltage is small.
The measurement results are shown in Table 2.

(3) Measurement of luminance half-life The time required for each manufactured light-emitting panel to emit light continuously under a constant current condition of ^2.5 mA / cm ² at room temperature to obtain half the initial luminance (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, each 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 an organic EL element has good light transmittance, It can also be seen that the drive voltage is kept low.
Moreover, also in durability (luminance half life), it turns out that the light emission panels 2-5 to 2-19 of this invention are excellent compared with the light emission panels 2-1 to 2-4 of a comparative example.

  Accordingly, it was confirmed that the light-emitting panel using the transparent electrode of the present invention can emit light with high luminance at a low driving voltage. In addition, it was confirmed that the driving voltage for obtaining the predetermined luminance can be reduced and the light emission life can be improved.

[Example 3]
<< Preparation of light emitting panel 3-1 >>
Double-sided light emitting panels 3-1 to 3-19 using a transparent electrode manufactured in the same manner as in Example 1 as a cathode (counter electrode 5a) were manufactured. Hereinafter, the production procedure will be described.

(1) Production of light-emitting panel 3-1 Patterning is performed on a substrate (NA-45, manufactured by AvanState Co., Ltd.) in which ITO (indium tin oxide) is formed as a 100 nm film on a 100 mm × 100 mm × 1.1 mm glass substrate. went. Thereafter, the transparent support substrate provided with the ITO transparent electrode was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.
This transparent substrate 13 was fixed to a substrate holder of a commercially available vacuum vapor deposition apparatus, and a vapor deposition mask was disposed opposite to the surface on which the transparent electrode 1 was formed. 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 forming each layer. In addition, the heating board used what was produced with the resistance heating material made from tungsten.

Next, the inside of the vapor deposition chamber of the vacuum vapor deposition apparatus was depressurized to a vacuum degree of 4 × 10 ⁻⁴ Pa, and each layer was formed as follows by sequentially energizing and heating the heating board containing each material.

  First, a heating board containing α-NPD as a hole transport injection material is energized and heated, and a hole transport injection layer 31 serving as both a hole injection layer and a hole transport layer made of α-NPD is transparent. A film was formed on the conductive layer 1 b constituting the electrode 1. At this time, the deposition rate was 0.1 to 0.2 nm / second, 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 energized independently to emit light composed of the host material H4 and the phosphorescent compound Ir-4. 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 deposition rate was 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 deposition rate was 0.1 to 0.2 nm / second, and the layer thickness was 10 nm.

  Thereafter, a heating board containing ET-6 represented by the following structural formula as an electron transporting material and a heating board containing potassium fluoride are energized independently to transport electrons composed of ET-6 and potassium fluoride. Layer 3d was deposited on hole blocking layer 33. At this time, the energization of the heating board was adjusted so that the 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 deposition rate was 0.01 to 0.02 nm / second, and the layer thickness was 1 nm.

  Thereafter, 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, the conductive layer 1b is used as the cathode as the light-transmitting counter electrode 5a made of Ag with a film thickness of 0.1 to 0.2 nm / second and a layer thickness of 5 nm in the processing chamber. A film was formed. Thus, the organic EL element 400 was formed on the transparent substrate 13.

  Thereafter, 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 interposed between the sealing material 17 and the transparent substrate 13 so as to surround the organic EL element 400. ). As the adhesive 19, an epoxy photocurable adhesive (Lux Track 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. Stopped.

  In forming the organic EL element 400, an evaporation mask is used for forming each layer, and the central 4.5 cm × 4.5 cm of the 5 cm × 5 cm transparent substrate 13 is defined as the light emitting region A, and the entire circumference of the light emitting region A is formed. A non-light emitting region B having a width of 0.25 cm was provided. Further, the ITO transparent electrode 1 serving as the anode and the counter electrode 5a made of Ag serving as the cathode are insulated by the light emitting functional layer 3 from the hole transport injection layer 31 to the electron injection layer 3e. The terminal part was formed in the shape pulled out to the periphery.

As described above, the organic EL element 400 was provided on the transparent substrate 13, and the light emitting panel 2-1 was sealed with the sealing material 17 and the adhesive 19.
In the light emitting panel 1, the emitted light h of each color generated in the light emitting layer 3c is extracted 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) Production of light-emitting panels 3-2 to 3-19 In production of the light-emitting panel 3-1, the light-emitting panels 3-2 to 3-3- were similarly performed except that the counter electrode 5a was changed to the transparent electrode shown in Table 3. 16 was produced.
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 a PET (polyethylene terephthalate) film.

<Evaluation of luminous panel>
About the produced light emitting panels 3-2 to 3-19, according to the following method, the light transmittance, the drive voltage, and the brightness | luminance half-life were measured.

(1) Measurement of light transmittance About each produced light emission panel, the light transmittance (%) in wavelength 550nm is set using the spectrophotometer (U-3300 by Hitachi, Ltd.) and the board | substrate of the transparent electrode of each light emission panel as a reference. Was measured.
Table 3 shows the measurement results.

(2) Measurement of drive voltage For each of the produced light-emitting panels, front luminance on 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) 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). For the measurement of luminance, a spectral radiance meter CS-1000 (manufactured by Konica Minolta) was used. It represents that it is so preferable that the numerical value of the obtained drive voltage is small.
Table 3 shows the measurement results.

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

(4) Summary As is apparent from Table 3, each 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 has a good light transmittance and a driving voltage. Is kept low.
Moreover, also in durability (luminance half life), it turns out that the light emission panels 3-5 to 3-19 are excellent compared with the light emission panels 3-1 to 3-4 of a comparative example.

  Accordingly, it was confirmed that the light-emitting panel using the transparent electrode of the present invention can emit light with high luminance at a low driving voltage. In addition, it was confirmed that the driving voltage for obtaining the predetermined luminance can be reduced and the light emission life can be improved.

DESCRIPTION OF SYMBOLS 1 Transparent electrode 1a Intermediate | middle layer 1b Conductive layer 3 Light emission functional layer 3a Hole injection layer 3b Hole transport layer 3c Light emission layer 3d Electron transport layer 3e Electron injection layer 5a, 5b, 5c Counter electrode 11 Substrate 13, 131 Transparent substrate ( substrate)
13a, 17a Light extraction surface 15 Auxiliary electrode 17 Sealing material 19 Adhesive 21 Illumination 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)

A transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer,
The conductive layer contains silver as a main component,
The said intermediate | middle layer contains the aromatic heterocyclic compound which has 2 or more of aromatic heterocyclic groups which have 3 or more hetero atoms in a molecule | numerator, The transparent electrode characterized by the above-mentioned. 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 [Formula _(1), E 1 ~E ₆ represents a carbon atom or a nitrogen atom, of which at least two represents a carbon atom. R ₁ represents a substituent. m1 represents an integer of 0 to 4. When m1 is 2 or more, R ₁ may be the same or different substituent. D ₁ represents an aromatic heterocyclic group having 3 or more heteroatoms. n1 represents the integer of 2-6. The plurality of D ₁ 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 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 a carbon atom or a nitrogen atom, and at least two of them represent a carbon atom. m11 represents an integer of 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 to 8. The plurality of D ₁₁ 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 [Formula _{(3), E} 21 ~E ₃₀ represents a carbon atom or a nitrogen atom, of which at least two represents a carbon atom. R ₂₁ represents a substituent. m21 represents an integer of 0 to 8. When 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 ₁₁ may be the same or different. ]   The transparent electrode according to claim 1, wherein the hetero atom is a nitrogen atom, an oxygen atom, or a sulfur atom.   The transparent electrode according to claim 1, 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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