JP6390373B2 - Transparent electrode, electronic device, and organic electroluminescence element - Google Patents

Description

  The present invention relates to a transparent electrode, an electronic device, and an organic electroluminescence element. More specifically, the present invention relates to a transparent electrode that has both light transmittance and conductivity and is excellent in durability, and an electronic device and an organic electroluminescence element including the transparent electrode.

  An organic EL element (also referred to as an organic electroluminescence element) using organic electroluminescence (hereinafter referred to as EL) is a thin-film type that can emit light at a low voltage of several volts to several tens of volts. It is a solid element 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 (see, for example, 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.

Therefore, by providing silver (Ag) having a high electrical conductivity as a conductive layer, and providing an intermediate layer made of a nitrogen-containing organic compound having a lone pair not involved in aromaticity under the conductive layer, Technologies that can produce a transparent electrode that has both excellent light transmittance and conductivity due to a strong interaction between the nitrogen-containing organic compound and silver have been proposed (see, for example, Patent Documents 3 to 6). .)
However, the nitrogen-containing organic compounds disclosed in Patent Documents 3 to 6 are compatible with the strong interaction force with silver and the industrial production suitability of the vacuum deposition method, which is the main formation method of the intermediate layer. A new problem has arisen that is insufficient.

One of the industrial production aptitudes of the vacuum deposition method is the stability of the intermediate layer material in a long-term overheated state. Similarly to the normal organic electroluminescence element material, the transparent electrode can be produced using the vacuum deposition method in the intermediate layer material of the present invention.
In the vacuum vapor deposition method, at the laboratory level, a small tungsten boat or the like is filled with a small amount of solid sample of about 100 mg, and current is applied to the boat until resistance reaches a desired vapor deposition rate (volatilization rate) to perform resistance heating. . On the other hand, in an industrial production method, a large crucible is filled with a large amount of sample in grams, and the material may be kept in an overheated state for several days to several weeks. Stability without thermal decomposition is required even if it is below.

In consideration of filling a large crucible with a large amount of sample, it is difficult for the heat to be transmitted to the sample to be uniform, and it is expected that the temperature is higher than a desired deposition temperature depending on the location.
In this way, the industrial production environment and production method are significantly different from those in laboratories, and materials with superior industrial production suitability from the viewpoint of stability in a superheated state over a long period of time and high heat resistance. It was sought after.

JP 2002-015623 A Japanese Unexamined Patent Publication No. 2006-164961 International Publication No. 2013/105569 International Publication No. 2013/141097 International Publication No. 2013/161750 International Publication No. 2013/180020

  The present invention has been made in view of the above problems and situations, and the solution is to use a material excellent in production suitability, which has both sufficient light transmission and conductivity, and excellent durability. To provide a transparent electrode, an electronic device including the transparent electrode, and an organic electroluminescence element.

As a result of examining the cause of the above-mentioned problem in order to solve the above-mentioned problems, the present inventor is a transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer, The conductive layer contains a metal as a main component, and the intermediate layer contains a compound having a structure represented by the following general formula (1) or general formula (2). The present inventors have found that a transparent electrode having both conductivity 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.

〔一般式（１）中、Ｘ_１〜Ｘ_３は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_１〜Ｘ_３が、それぞれ独立に、炭素原子を表す場合、Ｒ_１ａ〜Ｒ_３ａは水素原子を表す。Ｘ_１〜Ｘ_３が、それぞれ独立に、窒素原子を表す場合、Ｒ_１ａ〜Ｒ_３ａは非共有電子対を表す。Ｙ_１〜Ｙ_７は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｚ_１〜Ｚ_５は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_１〜Ｙ_７及びＺ_１〜Ｚ_５が炭素原子の場合、Ｒ_１〜Ｒ_１１は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_１〜Ｙ_７及びＺ_１〜Ｚ_５が窒素原子の場合、Ｒ_１〜Ｒ_１１は、それぞれ独立に、非共有電子対を表す。環Ａは、炭素原子とともに形成される芳香族環を表し、さらに置換基を有していてもよく、それらの置換基が互いに結合して環を形成してもよい。〕

〔一般式（２）中、Ｘ_４〜Ｘ_６は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_４〜Ｘ_６が、それぞれ独立に、炭素原子を表す場合、Ｒ_４ａ〜Ｒ_６ａは水素原子を表す。Ｘ_４〜Ｘ_６が、それぞれ独立に、窒素原子を表す場合、Ｒ_４ａ〜Ｒ_６ａは非共有電子対を表す。Ｙ_８〜Ｙ_１４は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｚ_６〜Ｚ_１０は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_８〜Ｙ_１４及びＺ_６〜Ｚ_１０が炭素原子の場合、Ｒ_１２〜Ｒ_２２は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_８〜Ｙ_１４及びＺ_６〜Ｚ_１０が窒素原子の場合、Ｒ_１２〜Ｒ_２２は、それぞれ独立に、非共有電子対を表す。環Ｂは、炭素原子とともに形成される芳香族環を表し、さらに置換基を有していてもよく、それらの置換基が互いに結合して環を形成してもよい。〕 1. A transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer,
The conductive layer contains a metal as a main component,
The said intermediate | middle layer contains the compound which has a structure represented by following General formula (1) or General formula (2), The transparent electrode characterized by the above-mentioned.

[In General Formula (1), X < ₁ > -X < ₃ > represents a carbon atom or a nitrogen atom each independently. X ₁ to X ₃ are each independently, may represent a carbon _atom, R 1a _{to R 3a} represents a hydrogen atom. When X _{1 to} X ₃ each independently represent a nitrogen atom, R _{1a to} R _3a represent an unshared electron pair. Y _{1 to} Y ₇ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{1 to} Z ₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are carbon atoms, R _{1 to} R ₁₁ each independently represent a hydrogen atom or a substituent. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are nitrogen atoms, R _{1 to} R ₁₁ each independently represent an unshared electron pair. Ring A represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring. ]

[In General Formula (2), X _{4 to} X ₆ each independently represents a carbon atom or a nitrogen atom. When X < ₄ > -X < ₆ > represents a carbon atom each independently, R < _4a > -R < _6a > represents a hydrogen atom. When X _{4 to} X ₆ each independently represent a nitrogen atom, R _{4a to} R _6a represent an unshared electron pair. Y _{8 to} Y ₁₄ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{6 to} Z ₁₀ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₈ > -Y < ₁₄ > and Z < ₆ > -Z < ₁₀ > are carbon atoms, R < ₁₂ > -R < ₂₂ > represents a hydrogen atom or a substituent each independently. When Y _{8 to} Y ₁₄ and Z _{6 to} Z ₁₀ are nitrogen atoms, R _{12 to} R ₂₂ each independently represent an unshared electron pair. Ring B represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring. ]

  2. 2. The transparent electrode according to claim 1, wherein the conductive layer contains at least one of gold, silver and copper as a main component.

  3. 3. The transparent electrode according to item 1 or 2, wherein the conductive layer contains silver as a main component.

4). Two or more of X _{1 to} X _{3 in} the general formula (1) represent a nitrogen atom, and two or more of X _{4 to} X _{6 in} the general formula (2) are nitrogen. The transparent electrode according to any one of Items 1 to 3, which represents an atom.

〔一般式（３）中、Ｘ_７〜Ｘ_９は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_７〜Ｘ_９が、それぞれ独立に、炭素原子を表す場合、Ｒ_７ａ〜Ｒ_９ａは水素原子を表す。Ｘ_７〜Ｘ_９が、それぞれ独立に、窒素原子を表す場合、Ｒ_７ａ〜Ｒ_９ａは非共有電子対を表す。Ｙ_１５〜Ｙ_２１は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_１５〜Ｙ_２１が炭素原子の場合、Ｒ_２３〜Ｒ_２９は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_１５〜Ｙ_２１が窒素原子の場合、Ｒ_２３〜Ｒ_２９は、それぞれ独立に、非共有電子対を表す。Ｙ_２２〜Ｙ_２８は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_２２〜Ｙ_２８が炭素原子の場合、Ｒ_３０〜Ｒ_３６は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_２２〜Ｙ_２８が窒素原子の場合、Ｒ_３０〜Ｒ_３６は、それぞれ独立に、非共有電子対を表す。Ｚ_１１〜Ｚ_１５は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｒ_３７〜Ｒ_４０は、それぞれ独立に、水素原子、置換基又は非共有電子対のいずれかを表す。〕

〔一般式（４）中、Ｘ_１０〜Ｘ_１２は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_１０〜Ｘ_１２が、それぞれ独立に、炭素原子を表す場合、Ｒ_１０ａ〜Ｒ_１２ａは水素原子を表す。Ｘ_１０〜Ｘ_１２が、それぞれ独立に、窒素原子を表す場合、Ｒ_１０ａ〜Ｒ_１２ａは非共有電子対を表す。Ｙ_２９〜Ｙ_３５は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_２９〜Ｙ_３５が炭素原子の場合、Ｒ_４１〜Ｒ_４７は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_２９〜Ｙ_３５が窒素原子の場合、Ｒ_４１〜Ｒ_４７は、それぞれ独立に、非共有電子対を表す。Ｙ_３６〜Ｙ_４２は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_３６〜Ｙ_４２が炭素原子の場合、Ｒ_４８〜Ｒ_５４は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_３６〜Ｙ_４２が窒素原子の場合、Ｒ_４８〜Ｒ_５４は、それぞれ独立に、非共有電子対を表す。Ｚ_１６〜Ｚ_２０は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｒ_５５〜Ｒ_５８は、それぞれ独立に、水素原子、置換基又は非共有電子対のいずれかを表す。〕 5. The compound having the structure represented by the general formula (1) has a structure represented by the following general formula (3),
The compound having the structure represented by the general formula (2) has a structure represented by the following general formula (4), according to any one of the first to third aspects, Transparent electrode.

[In General Formula (3), X _{7 to} X ₉ each independently represent a carbon atom or a nitrogen atom. When X < ₇ > -X < ₉ > represents a carbon atom each independently, R _<7a > -R < _9a > represents a hydrogen atom. When X < ₇ > -X < ₉ > represents a nitrogen atom each independently, R _<7a > -R < _9a > represents a lone pair. Y _{15 to} Y ₂₁ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₁₅ to Y ₂₁ is a carbon _atom, R 23 _{to R 29} each independently represent a hydrogen atom or a substituent. When Y < ₁₅ > -Y < ₂₁ > is a nitrogen atom, R < ₂₃ > -R < ₂₉ > represents an unshared electron pair each independently. Y _{22 to} Y ₂₈ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₂ > -Y < ₂₈ > is a carbon atom, R < ₃₀ > -R < ₃₆ > represents a hydrogen atom or a substituent each independently. When Y < ₂₂ > -Y < ₂₈ > is a nitrogen atom, R < ₃₀ > -R < ₃₆ > represents an unshared electron pair each independently. Z _{11 to} Z ₁₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. R < ₃₇ > -R < ₄₀ > represents either a hydrogen atom, a substituent, or an unshared electron pair each independently. ]

[In General Formula (4), X < ₁₀ > -X < ₁₂ > represents a carbon atom or a nitrogen atom each independently. When X < ₁₀ > -X < ₁₂ > represents a carbon atom each independently, R _<10a > -R < _12a > represents a hydrogen atom. When X < ₁₀ > -X < ₁₂ > represents a nitrogen atom each independently, R _<10a > -R < _12a > represents a lone pair. Y _{29 to} Y ₃₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₉ > -Y < ₃₅ > is a carbon atom, R < ₄₁ > -R < ₄₇ > represents a hydrogen atom or a substituent each independently. When Y < ₂₉ > -Y < ₃₅ > is a nitrogen atom, R < ₄₁ > -R < ₄₇ > represents an unshared electron pair each independently. Y _{36 to} Y ₄₂ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₃₆ to Y ₄₂ is a carbon _atom, R 48 _{to R 54} each independently represent a hydrogen atom or a substituent. When Y < ₃₆ > -Y < ₄₂ > is a nitrogen atom, R < ₄₈ > -R < ₅₄ > represents an unshared electron pair each independently. Z ₁₆ to Z ₂₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. R ₅₅ to R ₅₈ each independently represents any of a hydrogen atom, a substituent or an unshared electron pair. ]

〔一般式（５）中、Ｘ_１３〜Ｘ_１５は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_１３〜Ｘ_１５が、それぞれ独立に、炭素原子を表す場合、Ｒ_１３ａ〜Ｒ_１５ａは水素原子を表す。Ｘ_１３〜Ｘ_１５が、それぞれ独立に、窒素原子を表す場合、Ｒ_１３ａ〜Ｒ_１５ａは非共有電子対を表す。Ｙ_４３〜Ｙ_４９は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_４３〜Ｙ_４９が炭素原子の場合、Ｒ_５９〜Ｒ_６５は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_４３〜Ｙ_４９が窒素原子の場合、Ｒ_５９〜Ｒ_６５は、それぞれ独立に、非共有電子対を表す。Ｙ_５０〜Ｙ_５６は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_５０〜Ｙ_５６が炭素原子の場合、Ｒ_６６〜Ｒ_７２は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_５０〜Ｙ_５６が窒素原子の場合、Ｒ_６６〜Ｒ_７２は、それぞれ独立に、非共有電子対を表す。Ｒ_７３及びＲ_７４は、それぞれ独立に、水素原子又は置換基のいずれかを表す。〕

〔一般式（６）中、Ｘ_１６〜Ｘ_１８は、それぞれ独立に、炭素原子又は窒素原子を表す。Ｘ_１６〜Ｘ_１８が、それぞれ独立に、炭素原子を表す場合、Ｒ_１６ａ〜Ｒ_１８ａは水素原子を表す。Ｘ_１６〜Ｘ_１８が、それぞれ独立に、窒素原子を表す場合、Ｒ_１６ａ〜Ｒ_１８ａは非共有電子対を表す。Ｙ_５７〜Ｙ_６３は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_５７〜Ｙ_６３が炭素原子の場合、Ｒ_７５〜Ｒ_８１は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_５７〜Ｙ_６３が窒素原子の場合、Ｒ_７５〜Ｒ_８１は、それぞれ独立に、非共有電子対を表す。Ｙ_６４〜Ｙ_７０は、それぞれ独立に、炭素原子又は窒素原子を表し、少なくとも一つは窒素原子を表す。Ｙ_６４〜Ｙ_７０が炭素原子の場合、Ｒ_８２〜Ｒ_８８は、それぞれ独立に、水素原子又は置換基を表す。Ｙ_６４〜Ｙ_７０が窒素原子の場合、Ｒ_８２〜Ｒ_８８は、それぞれ独立に、非共有電子対を表す。Ｒ_８９及びＲ_９０は、それぞれ独立に、水素原子又は置換基のいずれかを表す。〕 6). The compound having a structure represented by the general formula (3) has a structure represented by the following general formula (5),
6. The transparent electrode according to item 5, wherein the compound having a structure represented by the general formula (4) has a structure represented by the following general formula (6).

[In General Formula (5), X < ₁₃ > -X < ₁₅ > represents a carbon atom or a nitrogen atom each independently. When X < ₁₃ > -X < ₁₅ > represents a carbon atom each independently, R _<13a > -R < _15a > represents a hydrogen atom. When X < ₁₃ > -X < ₁₅ > represents a nitrogen atom each independently, R _<13a > -R < _15a > represents a lone pair. Y _{43 to} Y ₄₉ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₄₃ to Y ₄₉ is a carbon _atom, R 59 _{to R 65} each independently represent a hydrogen atom or a substituent. If Y ₄₃ to Y ₄₉ is a nitrogen _atom, R 59 _{to R 65} each independently represent a non-covalent electron pair. Y _{50 to} Y ₅₆ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₀ to Y ₅₆ is a carbon _atom, R 66 _{to R 72} each independently represent a hydrogen atom or a substituent. If Y ₅₀ to Y ₅₆ is a nitrogen _atom, R 66 _{to R 72} each independently represent a non-covalent electron pair. R ₇₃ and R ₇₄ each independently represent either a hydrogen atom or a substituent. ]

[In General Formula (6), X _{16 to} X ₁₈ each independently represents a carbon atom or a nitrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a carbon _atom, R 16a _{to R 18a} represents a hydrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a nitrogen _atom, R 16a _{to R 18a} represents a lone pair. Y _{57 to} Y ₆₃ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₇ to Y ₆₃ is a carbon _atom, R 75 _{to R 81} each independently represent a hydrogen atom or a substituent. If Y ₅₇ to Y ₆₃ is a nitrogen _atom, R 75 _{to R 81} each independently represent a non-covalent electron pair. Y ₆₄ to Y ₇₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. If Y ₆₄ to Y ₇₀ is a carbon _atom, R 82 _{to R 88} each independently represent a hydrogen atom or a substituent. If Y ₆₄ to Y ₇₀ is a nitrogen _atom, R 82 _{to R 88} each independently represent a non-covalent electron pair. R ₈₉ and R ₉₀ each independently represent either a hydrogen atom or a substituent. ]

7). At least two of X _{13 to} X _{15 in} the general formula (5) represent a nitrogen atom, and at least two of X _{16 to} X _{18 in} the general formula (6). 7. The transparent electrode according to item 6, characterized in that represents a nitrogen atom.

8). In the general formula (5), at least one of R _{59 to} R ₇₄ , and in the general formula (6), at least one of R _{75 to} R ₉₀ is a linear substituent or branched. Item 8. The transparent electrode according to Item 6 or 7, wherein the transparent electrode is a substituent.

10. An electronic device comprising the transparent electrode according to any one of items 1 to 8 .

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

  According to the present invention, by using a material excellent in production suitability, a transparent electrode having sufficient light transmittance and conductivity and excellent in durability, an electronic device including the transparent electrode, and organic electroluminescence An element can be provided.

Although the expression mechanism and action mechanism of the effect of the present invention are not clarified, it is presumed as follows.
In the transparent electrode of the present invention, a conductive layer containing a metal as a main component is provided adjacent to the intermediate layer, and the intermediate layer is represented by the general formula (1) or the general formula (2). The compound which has a structure is contained.
When the compound according to the present invention is used for the intermediate layer, the metal atom first forms a two-dimensional nucleus on the surface of the intermediate layer containing the metal affinity compound having an atom having an affinity for the metal atom. The film is formed by a layer growth type (Frank-van der Merwe: FM type) film growth in which a two-dimensional single crystal layer is formed at the center.

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 suppressed by the compound having the structure represented by the general formula (1) or the general formula (2) which is a metal affinity compound contained in the intermediate layer, and the layer growth is performed. Is presumed to be 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.
Furthermore, the number of carbon-nitrogen bonds contained in the structure of the metal affinity compound is reduced as compared with the conventional one, and the heat-resistant stability of the compound is improved by increasing the carbon-carbon bonds, making it more industrial. It is presumed that production aptitude was excellent.

Schematic sectional view showing an example of the configuration of the transparent electrode of the present invention 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 comprises a conductive layer and an intermediate layer provided adjacent to the conductive layer, the conductive layer contains a metal as a main component, and the intermediate layer has the general formula ( It contains a compound having a structure represented by 1) or general formula (2). This feature is a technical feature common to the inventions according to claims 1 to 11.

  As an embodiment of the present invention, it is represented by the general formula (1) or the general formula (2) that the conductive layer contains at least one of gold, silver and copper as a main component. This is preferable because a strong interaction with a compound having a structure is formed.

  As an embodiment of the present invention, it is preferable that the conductive layer contains silver as a main component from the viewpoints of transparency and conductivity.

As an embodiment of the present invention, two or more of X _{1 to} X _{3 in} the general formula (1) represent a nitrogen atom, and X _{4 to} X _{6 in the} general formula (2). Of these, it is preferable that two or more of them represent nitrogen atoms from the viewpoint of strengthening the interaction with the metal that is the main component of the conductive layer.

  As an embodiment of the present invention, the compound having the structure represented by the general formula (1) has a structure represented by the general formula (3), and is represented by the general formula (2). It is preferable from a viewpoint of effect expression that the compound which has a structure which has a structure represented by the said General formula (4).

  As an embodiment of the present invention, a compound having a structure represented by the general formula (3) has a structure represented by the following general formula (5), and is represented by the general formula (4). It is preferable that the compound which has a structure which has a structure represented by following General formula (6) from a viewpoint of an effect expression.

As an embodiment of the present invention, at least two of X _{13 to} X _{15 in} the general formula (5) represent a nitrogen atom, and X ₁₆ in the general formula (6) It is possible that at least two or more of X ₁₈ represent nitrogen atoms, a strong mutual relationship between the compound having the structure represented by the general formula (5) or the general formula (6) and the metal contained in the intermediate layer It is preferable from the point that an action is formed.

In the embodiment of the present invention, at least one of R _{59 to} R _{74 in} the general formula (5) and at least one of R _{75 to} R _{90 in} the general formula (6) A chain-like substituent or a branched substituent is preferable from the viewpoint of increasing the compatibility with the solvent.

  Moreover, as an embodiment of the present invention, it is preferable that the conductive layer and the intermediate layer are both formed by a wet method from the viewpoint of the effect of the present invention.

  Moreover, the transparent electrode of this invention can be comprised suitably for an electronic device. Thereby, it is possible to obtain an electronic device having both sufficient light transmission and conductivity and excellent durability.

  Moreover, the transparent electrode of this invention can be comprised suitably for an organic electroluminescent element. Thereby, it is possible to obtain an organic electroluminescence element having both sufficient light transmittance and conductivity and excellent in 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>
As shown in FIG. 1A, the transparent electrode 1 includes a conductive layer 1b and an intermediate layer 1a provided adjacent to the conductive layer 1b. Specifically, 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 layers 1b are provided in this order.
The intermediate layer 1a is a layer containing a compound having a structure represented by the general formula (1) or the general formula (2). The conductive layer 1b is a layer composed of a metal as a main component, preferably gold, silver or copper, and most preferably based on silver. In the following description, silver will be described as an example.
The main component of the conductive layer 1b is a component having the highest component ratio among the components constituting the conductive layer 1b. The composition ratio of silver in the conductive layer 1b is preferably 60% by mass or more, more preferably 90% by mass or more, and particularly preferably 98% by mass or more.

Moreover, the transparency of the transparent electrode 1 means that the light transmittance at a measurement light wavelength of 550 nm is 50% or more.
Further, the sheet resistance value as the transparent electrode 1 is preferably 20Ω / □ or less, and the film thickness is usually selected in the range of 5 to 20 nm, preferably 5 to 12 nm.
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. Further, 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 that is 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, polysulfone , Polyether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylates, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Etc.

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%) measured by a method according to JIS K 7129-1992 of 0.01 g / m ² · 24 h or less. It is preferably a gas barrier film (also referred to as a gas barrier film). 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 gas barrier films are preferred.

  The material for forming the gas 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, such as silicon oxide, Silicon dioxide, silicon nitride, or the like can be used. Furthermore, in order to improve the brittleness of the gas barrier film, it is more preferable to have a laminated structure of a layer made of these inorganic materials (inorganic layer) and a layer made of organic material (organic layer). 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 gas barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but the method based on the atmospheric pressure plasma polymerization method described in JP-A-2004-68143 is particularly preferable.
On the other hand, when the substrate 11 is made of an opaque material, for example, a metal substrate such as aluminum or stainless steel, a film, an opaque resin substrate, a ceramic substrate, or the like can be used.

(Middle layer)
In the transparent electrode of the present invention, a conductive layer containing a metal as a main component is provided adjacent to the intermediate layer, and the intermediate layer is represented by the following general formula (1) or the following general formula (2). The compound which has a structure is contained.

In General Formula (1), X _{1 to} X ₃ each independently represent a carbon atom or a nitrogen atom. X ₁ to X ₃ are each independently, may represent a carbon _atom, R 1a _{to R 3a} represents a hydrogen atom. When X _{1 to} X ₃ each independently represent a nitrogen atom, R _{1a to} R _3a represent an unshared electron pair. Y _{1 to} Y ₇ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{1 to} Z ₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are carbon atoms, R _{1 to} R ₁₁ each independently represent a hydrogen atom or a substituent. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are nitrogen atoms, R _{1 to} R ₁₁ each independently represent an unshared electron pair. Ring A represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring.

In General Formula (2), X _{4 to} X ₆ each independently represent a carbon atom or a nitrogen atom. When X < ₄ > -X < ₆ > represents a carbon atom each independently, R < _4a > -R < _6a > represents a hydrogen atom. When X _{4 to} X ₆ each independently represent a nitrogen atom, R _{4a to} R _6a represent an unshared electron pair. Y _{8 to} Y ₁₄ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{6 to} Z ₁₀ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₈ > -Y < ₁₄ > and Z < ₆ > -Z < ₁₀ > are carbon atoms, R < ₁₂ > -R < ₂₂ > represents a hydrogen atom or a substituent each independently. When Y _{8 to} Y ₁₄ and Z _{6 to} Z ₁₀ are nitrogen atoms, R _{12 to} R ₂₂ each independently represent an unshared electron pair. Ring B represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring.

  The ring A contained in the general formula (1) and the ring B contained in the general formula (2) are preferably substituents having an aromatic six-membered ring skeleton. As an aromatic six-membered ring skeleton, for example, an aromatic hydrocarbon group (also called an aromatic carbocyclic group, an aryl group, etc., for example, a phenyl group, a p-chlorophenyl group, a mesityl group, a tolyl group, a xylyl group, a naphthyl group. , Anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.) or aromatic heterocyclic group (also referred to as heteroaryl group, for example, pyridyl group, pyridadyl group, pyrimidyl group , Pyrazyl group, triazyl group, etc.) are preferable, and it is particularly preferable to have a benzene ring skeleton or a triazine ring skeleton. Here, the aromatic six-membered ring skeleton, the benzene ring skeleton, and the triazine ring skeleton represent that each partial structure is included.

  In the present invention, at least one of the compounds having the structure represented by the general formula (1) or the general formula (2) has a nitrogen atom. When this nitrogen atom is a nitrogen atom having an unshared electron pair, it may be “a nitrogen atom having an unshared electron pair not involved in aromaticity”. “Nitrogen atom having an unshared electron pair not involved in aromaticity” refers to a nitrogen atom in which the unshared electron pair is not directly involved as an essential element in the aromaticity of the unsaturated cyclic compound. . That is, a non-localized π electron system on a conjugated unsaturated ring structure (aromatic ring) has a nitrogen atom in which a lone pair is not involved as an essential element for aromatic expression in the chemical structural formula Say.

  By having such a nitrogen atom, when the conductive layer is formed adjacent to the intermediate layer, the silver atoms constituting the conductive layer are not shared with the aromaticity contained in the intermediate layer. By interacting with nitrogen atoms having electron pairs, the diffusion distance of silver atoms on the surface of the intermediate layer was reduced, and aggregation of silver at specific locations could be suppressed.

Hereinafter, the “nitrogen atom having an unshared electron pair not involved in aromaticity” in the present invention will be described.
The nitrogen atom is a Group 15 element and has 5 electrons in the outermost shell. Of these, three unpaired electrons are used for covalent bonds with other atoms, and the remaining two become a pair of unshared electron pairs, so that the number of bonds of nitrogen atoms is usually three.

For example, an amino group (—NR ¹ R ² ), an amide group (—C (═O) NR ¹ R ² ), a nitro group (—NO ₂ ), a cyano group (—CN), a diazo group (—N ₂ ), An azide group (—N ₃ ), a urea bond (—NR ¹ C═ONR ² —), an isothiocyanate group (—N═C═S), a thioamide group (—C (═S) NR ¹ R ² ), and the like. These correspond to the “nitrogen atom having an unshared electron pair not involved in aromaticity” in the present invention. R ¹ and R ² each represent a substituent.
Among these, for example, the resonance formula of a nitro group (—NO ₂ ) can be expressed as follows. Strictly speaking, the unshared electron pair of the nitrogen atom in the nitro group is used for the resonance structure with the oxygen atom, but in the present invention, it is defined that the nitrogen atom of the nitro group also has an unshared electron pair.

On the other hand, a nitrogen atom can also create a fourth bond by utilizing an unshared electron pair. For example, as shown below, tetrabutylammonium chloride (abbreviation: TBAC) is a quaternary ammonium salt in which a fourth butyl group is ionically bonded to a nitrogen atom and has a chloride ion as a counter ion. . Tris (2-phenylpyridine) iridium (III) (abbreviation: Ir (ppy) ₃ ) is a neutral metal complex in which an iridium atom and a nitrogen atom are coordinated. Although these compounds have a nitrogen atom, the unshared electron pair is used for ionic bond and coordination bond, respectively. Therefore, in the present invention, “a nitrogen atom having an unshared electron pair not involved in aromaticity”. Is not applicable.

That is, the present invention effectively uses a lone pair of nitrogen atoms that are not used for bonding.
In the structural formulas shown below, the left side shows the structure of tetrabutylammonium chloride (abbreviation: TBAC), and the right side shows the structure of tris (2-phenylpyridine) iridium (III) (abbreviation: Ir (ppy) ₃ ).

  Moreover, a nitrogen atom is general as a hetero atom which can comprise an aromatic ring, and can contribute to the expression of aromaticity. Examples of the “nitrogen-containing aromatic ring” include pyridine ring, pyrazine ring, pyrimidine ring, triazine ring, pyrrole ring, imidazole ring, pyrazole ring, triazole ring, and tetrazole ring.

In the case of a pyridine ring, as shown below, in the conjugated (resonant) unsaturated ring structure arranged in a six-membered ring, the number of delocalized π electrons is 6, so 4n + 2 (n = 0 or natural number) ) Satisfies the Hückel rule. Since the nitrogen atom in the six-membered ring is substituted with —CH═, only one unpaired electron is mobilized to the 6π electron system, and an unshared electron pair is essential for aromatic expression. Not involved as a thing.
Therefore, the nitrogen atom of the pyridine ring corresponds to the “nitrogen atom having an unshared electron pair not involved in aromaticity” in the present invention. The molecular orbital of the pyridine ring is shown below.

In the case of a pyrrole ring, as shown below, one of the carbon atoms constituting the five-membered ring is substituted with a nitrogen atom, but the number of π electrons is six, which satisfies the Hückel rule. A nitrogen-containing aromatic ring. Since the nitrogen atom of the pyrrole ring is also bonded to a hydrogen atom, an unshared electron pair is mobilized to the 6π electron system.
Therefore, although the nitrogen atom of the pyrrole ring has an unshared electron pair, it has been utilized as an essential element for the expression of aromaticity. Therefore, in the present invention, the “unshared electron pair not involved in aromaticity” Does not correspond to "nitrogen atom having".
The molecular orbital of the pyrrole ring is shown below.

On the other hand, as shown below, the imidazole ring has a structure in which two nitrogen atoms in a five-membered ring are substituted at the 1-position and 3-position, and is also a nitrogen-containing aromatic ring having 6 π electrons. is there. The nitrogen atom N ¹ is a pyridine ring-type nitrogen atom in which only one unpaired electron is mobilized to the 6π-electron system, and the unshared electron pair is not used for aromaticity expression. On the other hand, the nitrogen atom N ² is a pyrrole-ring nitrogen atom that mobilizes an unshared electron pair to the 6π electron system.
Therefore, the nitrogen atom N ¹ of the imidazole ring corresponds to “a nitrogen atom having an unshared electron pair not involved in aromaticity” in the present invention. The molecular orbital of the imidazole ring is shown below.

The same applies to a condensed ring compound having a nitrogen-containing aromatic ring skeleton. For example, as shown below, δ-carboline is an azacarbazole compound in which a benzene ring skeleton, a pyrrole ring skeleton, and a pyridine ring skeleton are condensed in this order. The nitrogen atom N ³ of the pyridine ring mobilizes only one unpaired electron, and the nitrogen atom N ⁴ of the pyrrole ring mobilizes an unshared electron pair to the π-electron system, respectively, to form a ring. Together with 11 π electrons from the atoms, the total number of π electrons is 14 aromatic rings.

Therefore, among the two nitrogen atoms of δ-carboline, the nitrogen atom N ³ of the pyridine ring corresponds to the “nitrogen atom having an unshared electron pair not involved in aromaticity” in the present invention, but the nitrogen atom of the pyrrole ring N ⁴ does not fall into this category.
Thus, even when the pyridine ring or pyrrole ring is incorporated in a condensed ring compound, its effect is not inhibited or suppressed, and there is no difference from when it is used as a single ring. Absent. The molecular orbital of δ-carboline is shown below.

  As described above, the “nitrogen atom having an unshared electron pair not involved in aromaticity” defined in the present invention expresses a strong interaction between the unshared electron pair and the metal that is the main component of the conductive layer. Is important for. Such a nitrogen atom is preferably a nitrogen atom in a nitrogen-containing aromatic ring from the viewpoint of stability and durability.

The strength of the interaction between the nitrogen atom and the metal, particularly silver, can be inferred from the nucleophilic strength of the nitrogen atom. That is, the stronger the nucleophilicity, the stronger the coordination power to silver atoms and the stronger the interaction.
Furthermore, it is known that the strength of nucleophilicity is correlated with the strength of basicity. The basicity according to the definition of Bronsted Raleigh is the property of receiving protons. In other words, it can be said that the attack target is protons.

In order to quantitatively understand the basic strength, it is preferable to refer to the pKa value (acid dissociation constant) of the conjugate acid. The conjugate acid is a form in which protons are added to the base, and the pKa value indicates that the smaller the value, the stronger the acidity (proton releasing ability).
Therefore, the larger the pKa value of the conjugate acid, the stronger the basicity.

HA represents an acid, B represents a base, A ⁻ represents a conjugate base, and HB ⁺ represents a conjugate acid.
The present invention utilizes the interaction between the nitrogen-containing aromatic ring compound in the intermediate layer and the metal. Therefore, from the above viewpoint, the pKa value of the conjugate acid of the main nitrogen-containing aromatic ring compound was referred. For the pKa value, the list at the end of the volume was used (see Table 1), Hiroshi Yamanaka, Satoshi Hino, Masako Nakagawa, Naoko Sakamoto, “New edition of heterocyclic compounds”, Kodansha Scientific, March 1, 2004. .

From the above viewpoint, imidazole, pyridine, quinoline, and isoquinoline are preferable when an aromatic heterocycle having a large pKa value of the conjugate acid, high availability of the reagent as a raw material, and easy organic synthesis is considered.
Furthermore, examples of the simplest structure in which as many of these aromatic heterocycles are introduced into the molecule as possible and considering the ease of organic synthesis include the following compounds.

In the compounds (1) to (4), the central aromatic six-membered ring is a triazine ring and has the same substituents at the 2, 4, and 6 positions of the triazine ring. This structure has quinoline at different positions as a substituent.
Although the compounds (1) to (4) were considered to have a structure sufficient to expect a strong interaction with silver, low resistance and high light transmission were obtained even when a transparent electrode was produced using the intermediate layer. It was not possible to make a transparent electrode satisfying the rate. The reason for this is that the symmetry of the molecular structure is too high, leading to aggregation and crystallization of the compound, and the intermediate layer using the compound is effective for forming a continuous and uniform conductive layer. Guess not to work.

  Next, compounds (5) and (6) were devised in which one of the three identical substituents was changed to a different substituent. These are structures in which at least one imidazole (see Table 1), which has the largest pKa value of the conjugate acid of the aromatic heterocyclic ring, is introduced as a substituent, and the remaining substituent is pyridine.

When a transparent electrode was produced by using the compound (5) and the compound (6) for the intermediate layer, it was not possible to produce a transparent electrode sufficiently satisfying low resistance and high light transmittance. This is a compound (5) and compound (6) that are thought to suppress aggregation and crystallinity by reducing intramolecular symmetry and to improve thin film stability, but are derived from the effects of low molecular weight and the like. This is probably because the heat stability is small.
Therefore, a compound (7) and compound (8) in which three substituents were changed to one imidazole and two quinolines were devised, and a transparent electrode was produced using the intermediate layer. It was found that an excellent transparent electrode that achieves transmittance can be produced.

The reason why it is preferable to use a compound having a structure such as compound (7) or compound (8) in the intermediate layer can be described from the viewpoint of improving heat resistance stability.
First, since the compound (7) and the compound (8) have a quinoline ring, which is a double condensed ring structure of an aromatic six-membered ring, as a substituent, the molecular weight is larger than that of a monocyclic pyridine ring. Further, a quinoline ring having a condensed ring structure, which is a wider π-conjugated ring, is considered to be a delocalized and more stable compound because an electron cloud spreads over a relatively wide range in the molecule.

  Furthermore, paying attention to the bonding mode of the compound (7) and the compound (8) with the central six-membered ring, by introducing two quinoline rings as substituents, the central six-membered ring and the three substituents are It is formed from a C—C bond and one C—N bond. In general, a C—C bond is a more stable and stronger bond mode compared to a C—N bond that has a large charge bias due to a difference in electronegativity between a carbon atom and a nitrogen atom. I can say that. For example, from the molecular orbitals of the compounds (5) and (7) shown above, the compound (1) in which the bonding mode between the central six-membered ring and the three substituents consists of three CN bonds, It is presumed that the compound has a stronger bond and improved heat stability than the compound (5) comprising two CN bonds.

The energy levels of HOMO and LUMO in the present invention are Gaussian 03 (Gaussian 03, Revision D02, MJ Frisch, et al, Gaussian, Inc., Wallingford CT, software for molecular orbital calculation manufactured by Gaussian, USA). 2004.) and using B3LYP / 6-31G * as a keyword, the structure of the target molecular structure was optimized (eV unit converted value).
It is known that the correlation between the calculated value obtained by this method and the experimental value is high as a background to the effectiveness of this calculated value.

  Compound (1), Compound (12), Compound (7) and Compound (3) shown below have a triazine ring center in common, and 0, 1, 2, and 3 quinolines as substituents, respectively. It is a compound having a number. Focusing on the atoms around the bond axis between these triazine rings and each substituent, the charge was calculated by molecular calculation.

The nitrogen atom of imidazole bonded to the carbon atom of the triazine ring has a negative charge of -0.52 to -0.53 due to its high electronegativity.
And since the carbon atom of the triazine ring is bonded to the two nitrogen atoms at both ends constituting the triazine ring, when the charge is originally large and the substituent is quinoline (bonded to the carbon atom), Although it is +0.43, when the substituent is imidazole (bonded with a nitrogen atom), the charge is further positively increased to +0.73 to +0.74.
The strength of the covalent bond can be determined by the difference in charge between the two atoms. For example, in the compound (1), the difference in charge between the carbon atom of the triazine ring and the nitrogen atom of the imidazole becomes very large as Δ1.27, while in the compound (12), the carbon atom of the triazine ring and the carbon atom of the quinoline Since the difference in charge is as small as Δ0.47, it can be said that the latter bond is stronger and more stable.

  Furthermore, these effects become more prominent as the number of nitrogen atoms constituting the central six-membered ring increases. The compound (9), compound (10), compound (11) and compound (7) shown below are compounds in which the central six-membered ring has a benzene ring, a pyridine ring, a pyrimidine ring and a triazine ring, respectively. In the same way as above, the charge around the bond axis between the central six-membered ring and the substituent was focused on and the charge was calculated by molecular calculation.

The charge of carbon atoms at the 2, 4, and 6 positions of the central six-membered ring increases positively as the number of nitrogen atoms in the central six-membered ring increases. For example, in the compound (7), when the substituent is quinoline (bonded to a carbon atom), the difference is as small as Δ0.47, but when the substituent is imidazole (bonded to a nitrogen atom), it is extremely large as Δ1.13. Become.
In other words, when a pyrimidine ring or triazine ring composed of many nitrogen atoms is used, the charge of carbon atoms on the ring inevitably increases due to the electron withdrawing properties, When it is bonded to the bonded substituent, the charge is further positively increased.
In order to improve the thermal stability as a more stable and strong bond by reducing the difference in charge of atoms around the bond axis, the number of C—C bonds in the molecule is increased, ie at least two C—C. It is necessary to introduce a bond.

  For several reasons listed above, the intermediate layer contains compounds having a structure represented by the general formula (1) or the general formula (2) (for example, the compounds (7) and (8)), The present inventors have found that a transparent electrode having excellent thermal stability and excellent industrial productivity can be realized, and the present invention has been achieved.

From the above viewpoint, two or more of X _{1 to} X _{3 in} the general formula (1) represent a nitrogen atom, and among X _{4 to} X _{6 in} the general formula (2), It is preferable that two or more represent a nitrogen atom from the point which can form interaction effectively with metals, such as gold | metal | money, silver, or copper contained in an intermediate | middle layer.

  In a more preferred embodiment of the present invention, the compound having a structure represented by the general formula (1) has a structure represented by the general formula (3) and has a structure represented by the general formula (2). Is having a structure represented by the general formula (4).

In General Formula (3), X _{7 to} X ₉ each independently represent a carbon atom or a nitrogen atom. When X < ₇ > -X < ₉ > represents a carbon atom each independently, R _<7a > -R < _9a > represents a hydrogen atom. When X < ₇ > -X < ₉ > represents a nitrogen atom each independently, R _<7a > -R < _9a > represents a lone pair. Y _{15 to} Y ₂₁ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₁₅ to Y ₂₁ is a carbon _atom, R 23 _{to R 29} each independently represent a hydrogen atom or a substituent. When Y < ₁₅ > -Y < ₂₁ > is a nitrogen atom, R < ₂₃ > -R < ₂₉ > represents an unshared electron pair each independently. Y _{22 to} Y ₂₈ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₂ > -Y < ₂₈ > is a carbon atom, R < ₃₀ > -R < ₃₆ > represents a hydrogen atom or a substituent each independently. When Y < ₂₂ > -Y < ₂₈ > is a nitrogen atom, R < ₃₀ > -R < ₃₆ > represents an unshared electron pair each independently. Z _{11 to} Z ₁₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. R < ₃₇ > -R < ₄₀ > represents either a hydrogen atom, a substituent, or an unshared electron pair each independently.

In general formula (4), X < ₁₀ > -X < ₁₂ > represents a carbon atom or a nitrogen atom each independently. When X < ₁₀ > -X < ₁₂ > represents a carbon atom each independently, R _<10a > -R < _12a > represents a hydrogen atom. When X < ₁₀ > -X < ₁₂ > represents a nitrogen atom each independently, R _<10a > -R < _12a > represents a lone pair. Y _{29 to} Y ₃₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₉ > -Y < ₃₅ > is a carbon atom, R < ₄₁ > -R < ₄₇ > represents a hydrogen atom or a substituent each independently. When Y < ₂₉ > -Y < ₃₅ > is a nitrogen atom, R < ₄₁ > -R < ₄₇ > represents an unshared electron pair each independently. Y _{36 to} Y ₄₂ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₃₆ to Y ₄₂ is a carbon _atom, R 48 _{to R 54} each independently represent a hydrogen atom or a substituent. When Y < ₃₆ > -Y < ₄₂ > is a nitrogen atom, R < ₄₈ > -R < ₅₄ > represents an unshared electron pair each independently. Z ₁₆ to Z ₂₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. R ₅₅ to R ₅₈ each independently represents any of a hydrogen atom, a substituent or an unshared electron pair.

  In addition, the compound having the structure represented by the general formula (3) has the structure represented by the general formula (5), and the compound having the structure represented by the general formula (4) is represented by the general formula (6). It is preferable to have a structure represented by

In General Formula (5), X _{13 to} X ₁₅ each independently represent a carbon atom or a nitrogen atom. When X < ₁₃ > -X < ₁₅ > represents a carbon atom each independently, R _<13a > -R < _15a > represents a hydrogen atom. When X < ₁₃ > -X < ₁₅ > represents a nitrogen atom each independently, R _<13a > -R < _15a > represents a lone pair. Y _{43 to} Y ₄₉ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₄₃ to Y ₄₉ is a carbon _atom, R 59 _{to R 65} each independently represent a hydrogen atom or a substituent. If Y ₄₃ to Y ₄₉ is a nitrogen _atom, R 59 _{to R 65} each independently represent a non-covalent electron pair. Y _{50 to} Y ₅₆ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₀ to Y ₅₆ is a carbon _atom, R 66 _{to R 72} each independently represent a hydrogen atom or a substituent. If Y ₅₀ to Y ₅₆ is a nitrogen _atom, R 66 _{to R 72} each independently represent a non-covalent electron pair. R ₇₃ and R ₇₄ each independently represent either a hydrogen atom or a substituent.

In the general formula _{(6), X} 16 ~X ₁₈ each independently represents a carbon atom or a nitrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a carbon _atom, R 16a _{to R 18a} represents a hydrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a nitrogen _atom, R 16a _{to R 18a} represents a lone pair. Y _{57 to} Y ₆₃ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₇ to Y ₆₃ is a carbon _atom, R 75 _{to R 81} each independently represent a hydrogen atom or a substituent. If Y ₅₇ to Y ₆₃ is a nitrogen _atom, R 75 _{to R 81} each independently represent a non-covalent electron pair. Y ₆₄ to Y ₇₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. If Y ₆₄ to Y ₇₀ is a carbon _atom, R 82 _{to R 88} each independently represent a hydrogen atom or a substituent. If Y ₆₄ to Y ₇₀ is a nitrogen _atom, R 82 _{to R 88} each independently represent a non-covalent electron pair. R ₈₉ and R ₉₀ each independently represent either a hydrogen atom or a substituent.

At least two of X _{13 to} X _{15 in} the general formula (5) represent a nitrogen atom, and at least two of X _{16 to} X _{18 in} the general formula (6). Represents a nitrogen atom from the viewpoint that a stronger interaction can be formed.

In the general formula (5), at least one of R _{59 to} R ₇₄ , and in the general formula (6), at least one of R _{75 to} R ₉₀ is a linear substituent or branched. A substituent is preferred.

In the general formulas (1) to (6), examples of the substituent represented by R _{1 to} R ₉₀ include an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, Hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, etc.), alkynyl group ( For example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (also called aromatic carbocyclic group, aryl group, etc.), for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, Anthryl, azulenyl, acenaphthenyl, fluorenyl, phenanthryl, indenyl, pyrenyl Group, biphenylyl group, etc.), 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 , A 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, a pyrrolidyl group) Imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (for example, , Cyclopentyloxy group, cyclohe Siloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group etc.), cycloalkylthio Groups (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio groups (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl groups (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxy) Carbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, Methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group Etc.), 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, pyridyl) Carbonyl group, etc.), acyloxy groups (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbo group) Ruoxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylamino) Carbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl , Dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecyl group) Ureido 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, phenyl) Sulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, Acetylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group ( For example, 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 (eg, fluorine atom, chlorine atom, bromine atom), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl) Group, pentafluoroe Group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphate ester Examples include a group (for example, dihexyl phosphoryl group), a phosphite group (for example, diphenylphosphinyl group), a phosphono group, and the like.

Substituents represented by R ₁ to R ₉₀ may be substituted with a substituent represented by _R 1 _{to R 90.}
The compound having the structure represented by the general formulas (1) to (6) has a linear or branched substitution in the molecule from the viewpoint of improved solubility and excellent long-term storage after film formation. It preferably has a group.
Examples of the substituent having a branched structure include a branched alkyl group, a silyl group having two or more substitutions (for example, a trialkylsilyl group, a triarylsilyl group, etc.), a disubstituted amino group (for example, a dialkylamino group, a diarylamino group). Etc.) Disubstituted phosphoryl groups (for example, dialkyl phosphoryl group, diaryl phosphoryl group, etc.), and two or more substituents such as tolyl group, xylyl group, dimethylpyridyl group (preferably linear or branched substituents) ) And the like. In addition, as long as the branched structure is maintained, the constituent atoms contained in these branched substituents can be appropriately replaced with other atoms such as an oxygen atom, a nitrogen atom, and a sulfur atom.

Particularly preferred is a branched alkyl group having 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, such as isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, neopentyl group, dimethyl group. A hexyl group etc. are mentioned.
Although the specific example (I-1 to I-116) of the organic compound contained in the intermediate | middle layer 1a which concerns on this invention below is shown, it is not limited to this.

The organic compound according to the present invention can be easily synthesized according to a conventionally known synthesis method.
Hereinafter, although an example of the synthesis | combining method of the organic compound contained in the intermediate | middle layer 1a which concerns on this invention is shown, this invention is not limited to this.

[Synthesis Example: Synthesis of Exemplified Compound I-15]
(1) Synthesis of Intermediate-1 In a 100 ml eggplant flask, 6-bromoquinoline (5.0 g, 0.024 mol), Bis pinacolato diboron (15 g, 0.060 mol), Pd (dppf) ₂ (2.0 g, 0. 0024 mol) and K ₂ CO ₃ (5.0 g, 0.036 mol) in THF (50 ml) were stirred at 80 ° C. for 16 h.
Thereafter, the solution was transferred to a separatory funnel and extracted. Ethyl acetate and saturated brine were added to separate the organic phase and the aqueous phase, and then the organic phase was taken out and evaporated under reduced pressure. The obtained solid was purified by silica gel column chromatography to obtain a white solid of Intermediate-1 (5.4 g, yield 84%).

(2) Synthesis of Intermediate-2 In a 50 ml eggplant flask, 2,4,6-Trichloropyrimidine (1.7 g, 0.0093 mol), Intermediate-1 (5.0 g, 0.020 mol), Pd (PPh ₃ ) _A solution of ₄ (1.1 g, 0.93 mmol) and K ₂ CO ₃ (6.4 g, 0.047 mol) in Toluene (30 ml) was stirred at 90 ° C. for 16 hours.
Thereafter, the solution was transferred to a separatory funnel and extracted. Saturated saline was added to separate the organic phase and the aqueous phase, and then the organic phase was taken out and evaporated under reduced pressure. The obtained solid was purified by silica gel column chromatography to obtain a white solid of Intermediate-2 (1.6 g, yield 43%).

(3) Synthesis of Exemplified Compound I-15 In a 50 ml eggplant flask, Intermediate-2 (1.6 g, 0.0043 mol), Imidazole (0.89 g, 0.013 mol) and NaH (0.31 g, 0.013 mmol) Of DMF (20 ml) was stirred at 80 ° C. for 16 hours.
Thereafter, the solution was transferred to a separatory funnel and extracted. After adding THF and saturated saline to separate the organic phase and the aqueous phase, the organic phase was taken out and evaporated under reduced pressure. The obtained solid was purified by silica gel column chromatography to obtain a white solid (1.0 g, yield 58%) of exemplary compound I-15.

(Conductive layer)
The conductive layer 1b according to the present invention contains a metal as a main component, preferably contains gold, silver or copper as a main component, and particularly preferably contains silver as a main component. The conductive layer 1b is a layer formed on the intermediate layer 1a.
The conductive layer 1b may have a configuration in which a layer mainly composed of a metal is divided into a plurality of layers as needed.

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 less than 20 nm, the absorption component or reflection component of the layer is reduced, and the light transmittance of the transparent electrode 1 is preferably improved. Further, it is preferable that the layer thickness is thicker than 5 nm because the conductivity of the layer becomes sufficient.

  Note that, in the transparent electrode 1 having a laminated structure including the intermediate layer 1a as described above 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.

  The conductive layer 1b may be made of an alloy. Examples of such an alloy include silver magnesium (AgMg), silver copper (AgCu), silver palladium (AgPd), silver palladium copper (AgPdCu), silver, and the like. Indium (AgIn) and the like can be mentioned, and an alloy can be similarly used for gold and copper.

As a method for forming the conductive layer 1b, a wet process such as a coating method, an inkjet method, a coating method, or a dip method, a dry method such as a vapor deposition method (resistance heating, EB method, etc.), a sputtering method, a CVD method, or the like is used. Examples include a method using a process.
When the conductive layer 1b is formed by a wet method, it is preferable to use a conductive ink containing, for example, silver as a main component and an organic solvent. As an organic solvent, a conventionally well-known thing can be especially used without a restriction | limiting, unless the effect of the transparent electrode 1 of this invention is inhibited.

  When the conductive layer is formed using a wet method, it is preferable to use a conductive ink containing gold, silver, and copper as main components. These are not particularly limited as long as the object of the present invention is satisfied, but in the present configuration that realizes high light transmittance by reducing the film thickness of the conductive layer, nanoparticles having a small particle size of around 10 nm It is particularly preferable to use a conductive ink made of or a conductive ink made of a complex.

However, since many of the commercially available conductive inks are mainly used for the production of electric circuits and light reflection films, etc., they can be used in the usual way to produce thin films with excellent light transmittance. It is difficult to do. Therefore, it is necessary to devise a method of diluting the conductive ink with a solvent and optimizing thin film formation process conditions.
As the solvent to be diluted, a conventionally known solvent such as an organic solvent or an aqueous solvent can be used without particular limitation as long as the effect of the transparent electrode 1 of the present invention is not impaired.
Further, the conductive layer 1b is formed on the intermediate layer 1a, so that a high-temperature annealing treatment (for example, a heating process at 100 ° C. or higher) after the formation of the conductive layer is performed as necessary. Good.

<Effect of transparent electrode>
The transparent electrode 1 having the above-described configuration is configured with a metal as a main component on the intermediate layer 1a containing a compound having a structure represented by any one of the general formulas (1) to (6). A conductive layer 1b is provided. Thus, when the conductive layer 1b is formed on the intermediate layer 1a, the metal atoms contained in the conductive layer 1b are represented by the general formulas (1) to (6). It interacts with a compound having a structure represented by any of them, the diffusion distance of the metal atoms on the surface of the intermediate layer 1a is reduced, and metal aggregation is suppressed.

For example, in the formation of a conductive layer generally composed of silver as a main component, an island-like growth type (VW type) thin film is grown, so that silver particles are easily isolated in an island shape and the film thickness is increased. When it is thin, it is difficult to obtain conductivity, and the sheet resistance value becomes high.
Therefore, it is necessary to increase the film thickness in order to 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 having the configuration of the present invention, the aggregation of a metal, for example, silver, is suppressed on the intermediate layer 1a as described above, so that the conductive layer 1b composed mainly of silver is formed. In this case, a thin film is grown by a layer growth type (FM type).

  In addition, the transparency of the transparent electrode 1 of the present invention means that the light transmittance at a measurement light wavelength of 550 nm is 50% or more. However, each of the materials used as the intermediate layer 1a has a metal 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 of a metal as a main component has a thinner layer to ensure conductivity, thereby improving the conductivity of the transparent electrode 1 and light transmission. It is possible to achieve a balance with improvement in performance.

(Optical adjustment layer)
As shown in FIG. 1B, the transparent electrode 2 of the present invention preferably further includes an optical adjustment layer 2c on the substrate 12 in addition to the intermediate layer 2a and the conductive layer 2b. The optical adjustment layer 2c is a layer formed on the conductive layer 2b.
The optical adjustment layer may contain either an organic compound or an inorganic compound as a main component, and the layer constituting the optical adjustment layer may have a configuration in which a plurality of layers are laminated as necessary.

The optical adjustment layer is configured to sandwich the conductive layer together with the intermediate layer. In order to improve the light transmittance by reducing the reflection component of the conductive layer containing metal as a main component, such a configuration is preferable.
In order to produce an excellent transparent electrode with the maximum improvement in light transmittance, it is necessary to optimize it in consideration of the refractive index and film thickness of the compound contained in the intermediate layer and the optical adjustment layer. These can be estimated by optical simulation.

The optical adjustment layer is provided as appropriate for improving light transmittance. However, in view of being an adjacent layer of the conductive layer, a metal, particularly gold or silver, which is the main component of the conductive layer. Alternatively, it is preferable to contain a compound that interacts strongly with copper from the viewpoints of adhesion, scratch resistance, long-term storage, and the like.
Therefore, it is particularly preferable to use an aromatic heterocyclic compound containing a nitrogen atom having an unshared electron pair not involved in aromaticity.
In the following description, the transparent electrode 2 including the optical adjustment layer 2c can be used in the same manner even when the transparent electrode 1 including no optical adjustment layer is described.

≪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, an organic functional layer 3 configured using the transparent electrode 1, an organic material, and the like. 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 organic 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 which 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 organic functional layers 3, for example, the electron injection layer 3e may be made of an inorganic material.

In addition to these layers, the organic functional layer 3 may be laminated with a hole blocking layer, an electron blocking layer, or the like as necessary. Furthermore, the light emitting layer 3c may have a structure in which each color light emitting layer that generates light emitted in each wavelength region is laminated, and each of these color light emitting layers is laminated via a non-light emitting auxiliary layer. The auxiliary layer may function as a hole blocking layer or an electron blocking layer. Furthermore, the counter electrode 5a as a cathode may also have a laminated structure as necessary. In such a configuration, only a portion where the organic 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 organic functional layer 3 configured 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, it is assumed that 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 in a state of being insulated from each other by the organic 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 organic functional layer 3, the other layers of the organic 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 among the substrates 11 described above, the transparent substrate 11 having optical transparency 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 organic 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.
Further, the sheet resistance value as the counter electrode 5a is preferably several hundred Ω / □ or less, and the film thickness is usually selected within a 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 contains a light emitting material, and among them, it is preferable that a phosphorescent dopant (phosphorescent material, phosphorescent compound, phosphorescent compound) is contained as the light emitting material.
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 within a range of 1 to 50 nm, and more preferably adjusted within 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, and a phosphorescent light emitting dopant (phosphorescent compound) and a fluorescent dopant (fluorescent light emitting material, fluorescent compound) are mixed. It may be configured.
The light emitting layer 3c contains a host compound (light emitting host) and a light emitting material (light emitting dopant), and it is preferable that the light emitting material emits more light.

(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 and 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 7121-2012 using DSC (Differential Scanning Colorimetry).

  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. No. 2002-302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, No. 2003/0175553, No. 2006/0280965. US Patent Application Publication No. 2005/0112407, US Patent Application Publication No. 2009/0017330, US Patent Application Publication No. 2009/0030202, US Patent Application Publication No. 2005/0238919 ,Country Publication No. 2001/039234, International Publication No. 2009/021126, International Publication No. 2008/056746, International Publication No. 2004/093207, International Publication No. 2005/089025, International Publication No. 2007/063796, International Publication No. International Publication No. 2007/063754, International Publication No. 2004/107822, International Publication No. 2005/030900, International Publication No. 2006/114966, International Publication No. 2009/086028, International Publication No. 2009/003898, International Publication No. Examples include 2012/023947, JP 2008-074939 A, JP 2007-254297 A, and European Patent No. 2034538.

(Luminescent material)
(1) Phosphorescence emission dopant As a luminescent material which can be used by this invention, a phosphorescence emission dopant is mentioned.
A phosphorescent dopant 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.). Although defined as being a compound of 01 or more, a preferable phosphorescence quantum yield is 0.1 or more.
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. The phosphorescence quantum yield in a solution can be measured using various solvents, but when using a phosphorescent dopant in the present invention, the above phosphorescence quantum yield (0.01 or more) is achieved in any solvent. It only has to be done.

There are two types of light emission principles of the phosphorescent dopant.
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 dopant to obtain light emission from the phosphorescent dopant. It is an energy transfer type.
The other is a carrier trap type in which the phosphorescent dopant becomes a carrier trap, and carrier recombination occurs on the phosphorescent dopant to emit light from the phosphorescent dopant. In any case, it is a condition that the excited state energy of the phosphorescent dopant is lower than the excited state energy of the host compound.

  The phosphorescent light emitting dopant can be appropriately selected from known materials used for the light emitting layer of a general organic EL device, and preferably contains a group 8-10 metal in the periodic table of elements. A complex compound, more preferably an iridium compound, an osmium compound, a platinum compound (platinum complex compound), or a rare earth complex, and most preferably an iridium compound.

In the present invention, at least one light emitting layer 3c may contain two or more phosphorescent light emitting dopants, and the concentration ratio of the phosphorescent light emitting dopant in the light emitting layer 3c varies in the thickness direction of the light emitting layer 3c. It may be.
The phosphorescent dopant 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.

Specific examples of known phosphorescent dopants that can be used in the present invention include compounds described in the following documents.
Nature, 395, 151 (1998), Appl. Phys. Lett. 78, 1622 (2001), Adv. Mater. , 19, 739 (2007), Chem. Mater. 17, 3532 (2005), Adv. Mater. , 17, 1059 (2005), International Publication No. 2009/100991, International Publication No. 2008/101842, International Publication No. 2003/040257, US Patent Application Publication No. 2006/835469, US Patent Application Publication No. 2006. No. 0202194, U.S. Patent Application Publication No. 2007/0087321, U.S. Patent Application Publication No. 2005/0244673, Inorg. Chem. , 40, 1704 (2001), Chem. Mater. 16, 2480 (2004), Adv. Mater. 16, 2003 (2004), Angew. Chem. lnt. Ed. , 2006, 45, 7800, Appl. Phys. Lett. 86, 153505 (2005), Chem. Lett. , 34, 592 (2005), Chem. Commun. , 2906 (2005), Inorg. Chem. , 42, 1248 (2003), International Publication No. 2009/050290, International Publication No. 2002/015645, International Publication No. 2009/000673, US Patent Application Publication No. 2002/0034656, and US Pat. No. 7,332,232. United States Patent Application Publication No. 2009/0108737, United States Patent Application Publication No. 2009/0039776, United States Patent No. 6921915, United States Patent No. 6,687,266, United States Patent Application Publication No. 2007/0190359. No., US Patent Application Publication No. 2006/0008670, US Patent Application Publication No. 2009/0165846, US Patent Application Publication No. 2008/0015355, US Pat. No. 7,250,226, US Patent No. 7396598 Writing, U.S. Patent Application Publication No. 2006/0263635, U.S. Patent Application Publication No. 2003/0138657, U.S. Patent Application Publication No. 2003/0152802, U.S. Patent No. 7090928, Angew. Chem. lnt. Ed. 47, 1 (2008), Chem. Mater. , 18, 5119 (2006), Inorg. Chem. 46, 4308 (2007), Organometallics, 23, 3745 (2004), Appl. Phys. Lett. , 74, 1361 (1999), International Publication No. 2002/002714, International Publication No. 2006/009024, International Publication No. 2006/056418, International Publication No. 2005/019373, International Publication No. 2005/123873, International Publication. No. 2005/123873, International Publication No. 2007/004380, International Publication No. 2006/082742, US Patent Application Publication No. 2006/0251923, US Patent Application Publication No. 2005/0260441, US Pat. No. 7,393,599. No. 7, U.S. Pat. No. 7,534,505, U.S. Pat. No. 7,445,855, U.S. Patent Application Publication No. 2007/0190359, U.S. Patent Application Publication No. 2008/0297033, U.S. Pat. No. 7,338,722. Letter, United States Published Patent Application No. 2002/0134984, U.S. Pat. No. 7,279,704, U.S. Patent Application Publication No. 2006/098120, U.S. Patent Application Publication No. 2006/103874, International Publication No. 2005/076380. International Publication No. 2010/032663, International Publication No. 2008/140115, International Publication No. 2007/052431, International Publication No. 2011/134013, International Publication No. 2011/157339, International Publication No. 2010/086089, International Publication No. Publication No. 2009/113646, International Publication No. 2012/020327, International Publication No. 2011/051404, International Publication No. 2011/004639, International Publication No. 2011/073149, US Patent Application Publication No. 2012/228583 , Rice Japanese Patent Application Publication No. 2012/212126, Japanese Patent Application Laid-Open No. 2012-069737, Japanese Patent Application Laid-Open No. 2011-181303, Japanese Patent Application Laid-Open No. 2009-114086, Japanese Patent Application Laid-Open No. 2003-81988, Japanese Patent Application Laid-Open No. 2002-302671. Japanese Patent Laid-Open No. 2002-363552.
Among these, a preferable phosphorescent dopant includes an organometallic complex having Ir as a central metal. More preferably, a complex containing at least one coordination mode among a metal-carbon bond, a metal-nitrogen bond, a metal-oxygen bond, and a metal-sulfur bond is preferable.

(2) Fluorescent dopant The fluorescent luminescent dopant (henceforth "fluorescent dopant") used for this invention is demonstrated.
The fluorescent dopant used in the present invention is a compound that can emit light from an excited singlet, and is not particularly limited as long as light emission from the excited singlet is observed.
Fluorescent dopants used in the present invention include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes Examples thereof include dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.
In recent years, light emitting dopants utilizing delayed fluorescence have been developed, and these may be used.
Specific examples of the luminescent dopant using delayed fluorescence include, for example, the compounds described in International Publication No. 2011/156793, Japanese Patent Application Laid-Open No. 2011-213643, Japanese Patent Application Laid-Open No. 2010-93181, and the like. Is not limited to these.

(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. Good.

  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 preferably a very thin film, and the layer thickness is preferably in the range of 1 nm to 10 μm, although it depends on the material.

(Hole transport layer)
The hole transport layer 3b is made of a hole transport material having a function of transporting holes, and in a broad sense, the hole injection layer 3a and the electron blocking layer are also included in the hole transport layer 3b. The hole transport layer 3b 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-4-308688 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA) in which three triphenylamine units described in the publication are linked in a starburst type Etc.

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 exists in the range of 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 multilayer structure of a plurality of layers.

As an electron transport material (also serving as a hole blocking material) constituting an electron transport material of the electron transport layer 3d having a single layer structure and a layer portion adjacent to the light emitting layer 3c in the electron transport layer 3d having a multilayer structure, it is injected from the cathode. It has only to have a function of transmitting electrons 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) The central metals of aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc. and these metal complexes are In, Mg, A metal complex replaced with Cu, Ca, Sn, Ga, or Pb can also be used as the material of 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 the material of the light emitting layer 3c can be used as the material of the electron transport layer 3d, and n-type-Si, n-type as in the case of the hole injection layer 3a and the hole transport layer 3b. 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 exists in the range of 5-200 nm. The electron transport layer 3d may have a single-layer structure made 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 also serving as the electron injection layer 3e.

(Blocking layer: hole blocking layer, electron blocking layer)
The blocking layer is provided as necessary in addition to the basic constituent layer of the organic functional layer 3 described above. For example, as described in JP-A Nos. 11-204258 and 11-204359, and “Organic EL elements and the forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). There is a 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 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 in a state of covering at least the organic functional layer 3 in a state in which the terminal portions of the transparent electrode 1 and the counter electrode 5a in the organic EL element 100 are exposed. In addition, an electrode may be provided on the sealing material 17 so that the transparent electrode 1 and the terminal portion of the counter electrode 5a of the organic EL element 100 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 and conforms to JIS K 7129-1992. The water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)%) 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.

The adhesive 19 for fixing the 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. It is 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 (25 ° C.) 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 organic 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 entry of a substance that causes deterioration of the organic 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. In particular, it is preferable to use a polymer film because it is lightweight 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 containing a compound having a structure represented by any one of the general formulas (1) to (3) on the transparent substrate 13 is 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 containing silver (or an alloy containing silver) as a main component is appropriately formed by an evaporation method or the like so as to have a layer thickness within a range of 5 to 20 nm, preferably within a range of 8 to 12 nm. A transparent electrode 1 which is formed on the intermediate layer 1a by the method and serves as an anode is produced.

Next, a hole injection layer 3a, a hole transport layer 3b, a light emitting layer 3c, an electron transport layer 3d, and an electron injection layer 3e are formed in this order on this, and the organic functional layer 3 is formed. 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 within 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 organic 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 organic functional layer 3 to the periphery of the transparent substrate 13 while being kept insulated from the transparent electrode 1 by the organic functional layer 3. Thereby, the organic EL element 100 is obtained. Thereafter, the sealing material 17 that covers at least the organic 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 that the organic functional layer 3 is consistently produced from the counter electrode 5a 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 light transmittance and conductivity according to the present invention is used as an anode, and an organic 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.

<< 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 organic functional layer 3 employs various configurations as necessary, as described in the first example. In such a configuration, only the portion where the organic 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 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.
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 within a 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 the deterioration of the organic functional layer 3.

  Among 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. For this reason, 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 light transmittance and conductivity according to the present invention is used as a cathode, and an organic functional layer 3 and a counter electrode 5b serving as an anode are provided thereon. 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 the counter electrode 5c is provided on the substrate 131 side, and the organic 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 organic 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 organic 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 above configuration, only the portion where the organic 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 silver (Ag) and gold (Au), and 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, and the surface facing the outside of the substrate 131 is the light extraction surface 131a.

<Effect of organic EL element>
In the organic EL element 300 described above, the electron transport layer 3d having the electron injecting property constituting the uppermost part of the organic functional layer 3 is used as the intermediate layer 1a, and the conductive layer 1b is provided on the intermediate layer 1a. The transparent electrode 1 composed of the 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, The transparent electrode 1 may be an anode. In this case, the organic functional layer 3 is, for example, in order from the counter electrode (cathode) 5c side on the substrate 131, for example, an electron injection layer 3e / electron transport layer 3d / light emitting layer 3c / hole transport layer 3b / hole injection layer 3a. Are stacked. And the transparent electrode 1 which consists of a laminated structure of the ultra-thin intermediate | middle layer 1a and the electroconductive layer 1b is provided in this upper part as an anode.

≪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.

≪7. Lighting device-1 >>
The organic EL element of the present invention can be used for a lighting device.
The organic EL element of the present invention 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 fit in the wavelength range corresponding to CF (color filter) characteristic. As described above, any one of the above-described 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.

≪8. 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 organic 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. In addition, although the display of "%" is used in an Example, unless otherwise indicated, "mass%" is represented.

[Example 1]
<< Preparation of transparent electrode >>
As described below, the transparent electrodes 101 to 123 were fabricated so that the area of the conductive region was 5 cm × 5 cm. The transparent electrode 101 was produced as a transparent electrode having a single layer structure consisting only of a conductive layer, and the transparent electrodes 102 to 123 were produced as transparent electrodes having a laminated structure of an intermediate layer and a conductive layer.

(1) Production of transparent electrode 101 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, the resistance heating boat made from tungsten was filled with silver (Ag), and was attached in the said vacuum chamber. Next, after depressurizing the vacuum tank to 4 × 10 ⁻⁴ Pa, the resistance heating boat is energized and heated, and the layer thickness is 8 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 101 having a single layer structure.

(2) Production of transparent electrode 102 A transparent non-alkali glass substrate is fixed to a substrate holder of a commercially available vacuum deposition apparatus, and the following comparative compound (1) is filled in a resistance heating boat made of tantalum, and these substrates The holder and the heating boat were attached to the first vacuum chamber of the vacuum evaporation apparatus. Moreover, the resistance heating boat made from tungsten was filled with silver, 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 the heating boat containing the comparative compound (1) was energized and heated, and the deposition rate was 0.1 to 0.2 nm / second. In this range, an intermediate layer made of the comparative compound (1) having a layer thickness of 30 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 boat containing silver was energized and heated, A conductive layer made of silver having a layer thickness of 8 nm was formed within the range of the deposition rate of 0.1 to 0.2 nm / second, and a transparent electrode 102 having a laminated structure of an intermediate layer and a conductive layer was produced.

(3) Production of transparent electrodes 103 and 104 Transparent electrodes 103 and 104 were produced in the same manner except that the thickness of the conductive layer was changed to 10 nm and 15 nm, respectively.

(4) Preparation of transparent electrodes 105 to 107 Transparent electrodes 105 to 107 were prepared in the same manner as in the preparation of the transparent electrodes 102 to 104 except that the constituent material of the intermediate layer was changed to the exemplified compound I-1.

(5) Production of transparent electrodes 108 to 115 Transparent electrodes 108 to 115 were produced in the same manner as the production of the transparent electrode 105 except that the constituent material of the intermediate layer was changed to the compounds shown in Table 2.

(6) Production of Transparent Electrode 116 A thin film was formed on a non-alkali glass base material by spin coating using a toluene solution of I-7. An intermediate layer containing I-7 having a layer thickness of 30 nm was provided by heating and drying at 150 ° C. for 1 hour.
On this intermediate layer, 1.0 ml of inkjet ink (TEC-IJ-010, manufactured by Ink Tec Co., Ltd.) made of complex silver as a conductive layer material was diluted 10 times with ethanol. After applying and patterning 0.1 ml of this diluted solution by spin coating, baking is performed at 120 ° C. for 30 minutes to form a conductive layer made of silver having a layer thickness of 8 nm, and a laminated structure of an intermediate layer and a conductive layer A transparent electrode 116 made of was prepared.

(7) Production of transparent electrode 117 A thin film was formed on a base made of alkali-free glass by using a toluene solution of I-8 by a spin coating method. An intermediate layer containing I-8 having a layer thickness of 30 nm was provided by heating and drying at 150 ° C. for 1 hour.
Next, after transferring the substrate formed up to the intermediate layer to a vacuum chamber and depressurizing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing silver was energized and heated, and the deposition rate was 0.1 to 0. A conductive layer made of silver having a layer thickness of 8 nm was formed within a range of 0.2 nm / second, and a transparent electrode 117 having a laminated structure of an intermediate layer and a conductive layer was produced.

(8) Production of Transparent Electrode 118 Transparent electrode 118 was produced in the same manner as production of transparent electrode 117 except that the constituent material of the intermediate layer was changed to the compounds shown in Table 2.

(9) Production of transparent electrodes 119 and 120 Transparent electrodes 119 and 120 were produced in the same manner except that the conductive layer was changed to the material shown in Table 2 in the production of the transparent electrode 105.

(10) Production of transparent electrodes 121 to 123 Transparent electrodes 121 to 123 were produced in the same manner except that the substrate was changed from non-alkali glass to PET (polyethylene terephthalate) film in the production of transparent electrodes 109, 114, and 117. .

<< Evaluation of transparent electrode >>
About the produced transparent electrodes 101-123, according to the following method, the light transmittance, sheet resistance value, and the light transmittance change (durability) under high temperature, high humidity were measured.

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

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

(3) Measurement of sheet resistance value change under high temperature and high humidity About each produced transparent electrode, it preserve | saved in temperature 100 degreeC / relative humidity 90% atmosphere, and measured sheet resistance value change. Specifically, the sheet resistance values before the start of the test and after the lapse of 500 hours were compared, the change was evaluated, and the results are shown in Table 2. The sheet resistance value was measured using a resistivity meter (MCP-T610 manufactured by Mitsubishi Chemical Analytech Co., Ltd.) and the sheet resistance value (Ω / □) was measured by a four-point probe constant current application method, and the change in resistance value from the initial sheet Was calculated. The change in the sheet resistance value of each transparent electrode under high temperature and high humidity is shown as a relative value with the change in the sheet resistance value of the transparent electrode 119 as 100, indicating that the smaller the value, the smaller the change and the better the durability. ing.

(4) Summary As is clear from Table 2, the transparent electrodes 109 to 123 of the present invention in which a conductive layer mainly composed of silver (Ag) is provided on the intermediate layer have a light transmittance of 50% or more. The sheet resistance value is suppressed to 38.2 Ω / □ or less. On the other hand, some of the transparent electrodes 101 to 104 of the comparative example had a light transmittance of less than 50%, and the sheet resistance value showed a value exceeding 38.2Ω / □.
Further, in terms of durability (change in sheet resistance value under high temperature and high humidity), the transparent electrodes 105 to 123 of the present invention are small and excellent in comparison with the transparent electrodes 101 to 104 of the comparative example. I understood.

In addition, even in a resin film such as PET (polyethylene terephthalate), by using the compound of the present invention for the intermediate layer, an evaluation result equivalent to that of non-alkali glass was obtained, so that the effect is exhibited regardless of the substrate. I was able to confirm.
From the above, it was confirmed that the transparent electrode of the present invention has high light transmittance and conductivity, and is further excellent in durability.

[Example 2]
<Production of light emitting panel>
Double-sided light emitting panels 401 to 423 using the transparent electrode of the present invention as an anode were manufactured. Hereinafter, the manufacturing procedure will be described with reference to FIG.

(1) Production of Light-Emitting Panel 401 First, the transparent substrate 101 produced in Example 1, that is, the transparent substrate 13 on which the transparent electrode 1 having only the conductive layer 1b is formed is used as a substrate holder of a commercially available vacuum deposition apparatus. It fixed and the vapor deposition mask was arrange | positioned facing the formation surface side of the transparent electrode 1. Moreover, each material which comprises the organic functional layer 3 was filled in each heating boat in a vacuum evaporation apparatus in the optimal quantity for film-forming of each layer. In addition, what was produced with the resistance heating material made from tungsten was used for the heating boat.

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 boat containing each material.
First, a heating boat containing α-NPD (4,4′-Bis [phenyl (1-naphthyl) amino] -1,1′-biphenyl) as a hole transport injection material is energized and heated, and α-NPD A hole transport injection layer 31 serving as both a hole injection layer and a hole transport layer 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 boat containing the host material H4 and the heating boat containing the phosphorescent dopant Ir-4 are energized independently, and the light emitting layer 3c containing the host material H4 and the phosphorescent dopant Ir-4. Was formed on the hole transport injection layer 31. At this time, the energization of the heating boat was adjusted so that the deposition rate was host material H4: phosphorescent dopant Ir-4 = 100: 6. The layer thickness was 30 nm.

  Next, the hole blocking layer 33 made of BAlq is heated by energizing a heating boat containing BAlq ([Bis (2-methyl-8-quinolinolate) -4- (phenylphenolato) aluminum]) as a hole blocking material. A film was formed 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 boat containing ET-6 shown below as an electron transporting material and a heating boat containing potassium fluoride were energized independently, and an electron transporting layer 3d containing ET-6 and potassium fluoride. Was formed on the hole blocking layer 33. At this time, the energization of the heating boat was adjusted so that the deposition rate was ET-6: potassium fluoride = 75: 25. The layer thickness was 30 nm.

  Next, a heating boat 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 transferred from the vapor deposition chamber of the vacuum vapor deposition apparatus to the processing chamber of the sputtering apparatus to which an 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 film thickness of 150 nm was formed as a cathode. As described above, 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 organic 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 light emitting panel 401 in which the organic EL element 400 was provided on the transparent substrate 13 and sealed with the sealing material 17 and the adhesive 19 was manufactured.
In the light emitting panel 401, 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 panel 402 The production of the light emitting panel 401 was the same except that the structural material of the intermediate layer 1a was changed to the comparative compound (2) and the transparent electrode 102 having a layer thickness changed to 40 nm was used. Thus, a light-emitting panel 402 was manufactured.

(3) Production of Light-Emitting Panels 403 and 404 Light-emitting panels 403 to 404 were produced in the same manner except that the thickness of the conductive layer 1b was changed to 10 nm and 15 nm, respectively.

(4) Production of light-emitting panels 405 to 407 Light-emitting panels 405 to 407 were produced in the same manner as in the production of the light-emitting panels 402 to 404 except that the constituent material of the intermediate layer 1a was changed to Exemplified Compound I-9.

(5) Production of light-emitting panels 408 to 415 Light-emitting panels 408 to 415 were produced in the same manner as the light-emitting panel 405 except that the constituent material of the intermediate layer 1a was changed to the compounds shown in Table 3.

(6) Production of Light-Emitting Panel 416 A thin film was formed by spin coating using a toluene solution of I-15 on a non-alkali glass substrate. An intermediate layer containing I-15 having a layer thickness of 40 nm was provided by heating and drying at 150 ° C. for 1 hour.
On this intermediate layer, 1.0 ml of inkjet ink (TEC-IJ-010, manufactured by Ink Tec Co., Ltd.) made of complex silver as a conductive layer material was diluted 10 times with ethanol. After applying and patterning 0.1 ml of this diluted solution by spin coating, baking is performed at 120 ° C. for 30 minutes to form a conductive layer made of silver having a layer thickness of 8 nm, and a laminated structure of an intermediate layer and a conductive layer A transparent electrode comprising:
In manufacturing the light-emitting panel 405, a light-emitting panel 416 was manufactured in the same manner except that the transparent electrode was used.

(7) Production of Light-Emitting Panel 417 A thin film was formed on a non-alkali glass base material by spin coating using a toluene solution of I-16. An intermediate layer containing I-16 having a layer thickness of 40 nm was provided by heating and drying at 150 ° C. for 1 hour.
Next, after transferring the substrate formed up to the intermediate layer to a vacuum chamber and depressurizing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing silver was energized and heated, and the deposition rate was 0.1 to 0. A conductive layer made of silver having a layer thickness of 8 nm was formed within a range of .2 nm / second, and a transparent electrode having a laminated structure of an intermediate layer and a conductive layer was produced.
In the manufacture of the light-emitting panel 405, a light-emitting panel 417 was manufactured in the same manner except that the transparent electrode was used.
(8) Production of Light-Emitting Panel 418 A light-emitting panel 418 was produced in the same manner as in the production of the light-emitting panel 417 except that the constituent material of the intermediate layer 1a was changed to the compounds shown in Table 3.

(9) Production of Light-Emitting Panels 419 and 420 Light-emitting panels 419 and 420 were produced in the same manner as the light-emitting panel 405 except that the constituent material of the conductive layer 1b was changed to the compounds shown in Table 3.

(10) Production of light-emitting panels 421 to 423 Light-emitting panels 421 to 423 were produced in the same manner except that the substrate was changed from non-alkali glass to PET (polyethylene terephthalate) film in the production of light-emitting panels 410, 414 and 417. .

<Evaluation of luminous panel>
About the produced light emitting panels 401-423, according to the following method, the external transmittance | permeability (durability) under a light transmittance, a drive voltage, and high temperature / humidity was measured.

(1) Measurement of light transmittance About each produced light emitting panel, using a spectrophotometer (U-3300 by Hitachi High-Technologies Corporation), with the transparent electrode substrate of each light emitting panel as a reference, light transmission at a measuring light wavelength of 550 nm The rate (%) was measured. The measurement results are shown in Table 3.

(2) Measurement of driving voltage The front luminance on both sides of the transparent electrode 1 side (that is, the transparent substrate 13 side) and the counter electrode 5a side (that is, the sealing material 17 side) of each of the produced light emitting panels is measured. 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 3.

(3) Measurement of change in external quantum efficiency (EQE) under high temperature and high humidity Each of the organic EL devices prepared above was allowed to emit light at 100 ° C. and 90% relative humidity under a constant current condition of ^2.5 mA / cm ^2. The emission luminance immediately after the start of light emission and the emission luminance after 500 hours from the start were measured using a spectral radiance meter CS-2000 (manufactured by Konica Minolta).
Relative light emission luminance after 500 hours from the light emission luminance immediately after the start of light emission was obtained, and this was used as a measure of External Quantum Efficiency (EQE). The change in EQE of each light-emitting panel under high temperature and high humidity is shown as a relative value where the EQE change of the light-emitting panel 419 is 100. The smaller the value, the smaller the change in emission luminance and the better the external quantum efficiency. Represents that. The measurement results are shown in Table 3.

(4) Summary As is clear from Table 3, each of the light emitting panels 405 to 423 of the present invention using the transparent electrode of the present invention as the anode of an organic EL element has a light transmittance of 61% or more, and a driving voltage. Is suppressed to 7.5 V or less. On the other hand, the light emitting panels 401 to 404 using the transparent electrode of the comparative example as the anode of the organic EL element have a light transmittance of less than 61%, and the driving voltage is higher than 7.5V. There was something.
Moreover, it turned out that the light emission panels 405-423 of this invention are excellent also in durability (external quantum efficiency change under high temperature, high humidity) compared with the light emission panels 401-404 of a comparative example.

The transparent electrode using the compound having the structure represented by the general formula (1) or (2) of the present invention can be used for various electronic devices. Among these, it has been found that the transparent electrode of the present invention can be effectively used in an organic electroluminescence element having the most severe restrictions among electronic devices from the viewpoint of sheet resistance.
Accordingly, the transparent electrode using the compound having the structure represented by the general formula (1) or (2) of the present invention is also applied to other electronic devices such as a liquid crystal display device, a solar cell, electronic paper, and a touch panel. It is considered possible.

An organic thin film solar cell and a touch panel were actually produced using the electrode produced with the transparent electrode 105 of Example 1 and confirmed to work well.
Thereby, it was confirmed that the light emitting panel using the transparent electrode of the present invention can emit light with high luminance with a low sheet resistance value.

[Example 3]
(1) Stability test in a long-term overheated state In order to evaluate the industrial productivity of the intermediate layer material of the present invention, the compound (1), the compound (5), the compound (7), the compound (8) and examples Compounds I-1 to I-8 were subjected to a stability test in a superheated state for a long time (referred to as test numbers 501 to 512, respectively). In Table 4, the number of C—C bonds represents the number of carbon-carbon bonds of the central aromatic six-membered ring of each compound. Hereinafter, the production procedure will be described.

The intermediate layer material shown in Table 4 was filled in a crucible by 1 g each and set in the material chamber of the thermo ball valved cell. Next, the inside of the vapor deposition chamber was depressurized to a vacuum degree of 4 × 10 ⁻⁴ Pa, and the crucible containing the intermediate layer material was energized. The energization was continued until the temperature indicated by the thermometer attached to the crucible reached a desired temperature described later.
The magnitude of the current applied to the crucible, that is, the temperature finally applied to the intermediate layer material is higher than the temperature when the deposition rate of the material is stabilized at 0.1 nm / second (within ± 0.05 nm / second). The temperature was 30 ° C higher. This is because it is presumed that the heat load applied to the material is larger in industrial production than in small scale production at the laboratory level.

  The thermo ball valved cell includes a material chamber, a valve control chamber, and a steam introduction path, and the flow rate of the material vapor generated from the material chamber can be adjusted by a valve. Therefore, when the value of energization to the crucible (temperature during resistance heating) is made constant, the deposition rate can be changed by opening and closing the valve, and if the valve is completely closed, the steam flows to the outside. There is nothing. This time, the valve was fully closed, and a desired temperature was continuously applied to the crucible for a total of 100 hours.

(2) Purity evaluation The above materials that have been subjected to a stability test in a superheated state for a long period of time are measured by high-performance liquid chromatography (HPLC), and the magnitude of the difference from the purity before the start of the test is compared. did. Each purity change is shown as a relative value with the value before the test being 100, and the closer the value is to 100, the smaller the change in purity and the better the stability.
On the other hand, when the numerical value of the purity change is small, it is suggested that many by-products derived from the pyrolyzate were generated after the test.
Moreover, in HPLC measurement, there is a restriction that the purity cannot be measured unless the sample is completely dissolved in a solvent. After the test, some of the collected samples were carbonized, and some insoluble components that were thought to be derived from the polymer were also found. In such cases, it is natural to analyze the dissolved components to obtain an accurate purity. Since it was not possible, the presence or absence of insoluble components was also shown. The measurement results are shown in Table 4.

(3) Summary As is clear from Table 4, the compound (7), the compound (8) and the materials I-1 to I-8 according to the present invention all have a purity change of 98.54 or more, almost 100. It was close to. Moreover, since there was no insoluble component, it was found that no thermal decomposition product or polymer was generated, and the material was excellent in industrial productivity.

1, 2 Transparent electrodes 1a, 2a Intermediate layer 1b, 2b Conductive layer 2c Optical adjustment layer 3 Organic functional layer 3a Hole injection layer 3b Hole transport layer 3c Light emitting layer 3d Electron transport layer 3e Electron injection layer 31 Hole transport injection Layer 33 Hole blocking layer 5a, 5b, 5c Counter electrode 11, 12 Substrate 13, 131 Transparent substrate (substrate)
13a, 131a Light extraction surface 15 Auxiliary electrode 17 Sealing material 19 Adhesive 21 Illumination device 22 Light emitting panel 23 Support substrate 100, 200, 300, 400 Organic EL element A Light emitting region B Non-light emitting region h Light emitting light

Claims (10)

A transparent electrode comprising a conductive layer and an intermediate layer provided adjacent to the conductive layer,
The conductive layer contains a metal as a main component,
The said intermediate | middle layer contains the compound which has a structure represented by following General formula (1) or General formula (2), The transparent electrode characterized by the above-mentioned.

[In General Formula (1), X < ₁ > -X < ₃ > represents a carbon atom or a nitrogen atom each independently. X ₁ to X ₃ are each independently, may represent a carbon _atom, R 1a _{to R 3a} represents a hydrogen atom. When X _{1 to} X ₃ each independently represent a nitrogen atom, R _{1a to} R _3a represent an unshared electron pair. Y _{1 to} Y ₇ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{1 to} Z ₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are carbon atoms, R _{1 to} R ₁₁ each independently represent a hydrogen atom or a substituent. When Y _{1 to} Y ₇ and Z _{1 to} Z ₅ are nitrogen atoms, R _{1 to} R ₁₁ each independently represent an unshared electron pair. Ring A represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring. ]

[In General Formula (2), X _{4 to} X ₆ each independently represents a carbon atom or a nitrogen atom. When X < ₄ > -X < ₆ > represents a carbon atom each independently, R < _4a > -R < _6a > represents a hydrogen atom. When X _{4 to} X ₆ each independently represent a nitrogen atom, R _{4a to} R _6a represent an unshared electron pair. Y _{8 to} Y ₁₄ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. Z _{6 to} Z ₁₀ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₈ > -Y < ₁₄ > and Z < ₆ > -Z < ₁₀ > are carbon atoms, R < ₁₂ > -R < ₂₂ > represents a hydrogen atom or a substituent each independently. When Y _{8 to} Y ₁₄ and Z _{6 to} Z ₁₀ are nitrogen atoms, R _{12 to} R ₂₂ each independently represent an unshared electron pair. Ring B represents an aromatic ring formed with a carbon atom, and may further have a substituent, and these substituents may be bonded to each other to form a ring. ]   The transparent electrode according to claim 1, wherein the conductive layer contains at least one of gold, silver, and copper as a main component.   The transparent electrode according to claim 1, wherein the conductive layer contains silver as a main component. Two or more of X _{1 to} X _{3 in} the general formula (1) represent a nitrogen atom, and two or more of X _{4 to} X _{6 in} the general formula (2) are nitrogen. The transparent electrode according to any one of claims 1 to 3, wherein the transparent electrode represents an atom. The compound having the structure represented by the general formula (1) has a structure represented by the following general formula (3),
The compound having the structure represented by the general formula (2) has a structure represented by the following general formula (4), according to any one of claims 1 to 3. Transparent electrode.

[In General Formula (3), X _{7 to} X ₉ each independently represent a carbon atom or a nitrogen atom. When X < ₇ > -X < ₉ > represents a carbon atom each independently, R _<7a > -R < _9a > represents a hydrogen atom. When X < ₇ > -X < ₉ > represents a nitrogen atom each independently, R _<7a > -R < _9a > represents a lone pair. Y _{15 to} Y ₂₁ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₁₅ to Y ₂₁ is a carbon _atom, R 23 _{to R 29} each independently represent a hydrogen atom or a substituent. When Y < ₁₅ > -Y < ₂₁ > is a nitrogen atom, R < ₂₃ > -R < ₂₉ > represents an unshared electron pair each independently. Y _{22 to} Y ₂₈ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₂ > -Y < ₂₈ > is a carbon atom, R < ₃₀ > -R < ₃₆ > represents a hydrogen atom or a substituent each independently. When Y < ₂₂ > -Y < ₂₈ > is a nitrogen atom, R < ₃₀ > -R < ₃₆ > represents an unshared electron pair each independently. Z _{11 to} Z ₁₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. R < ₃₇ > -R < ₄₀ > represents either a hydrogen atom, a substituent, or an unshared electron pair each independently. ]

[In General Formula (4), X < ₁₀ > -X < ₁₂ > represents a carbon atom or a nitrogen atom each independently. When X < ₁₀ > -X < ₁₂ > represents a carbon atom each independently, R _<10a > -R < _12a > represents a hydrogen atom. When X < ₁₀ > -X < ₁₂ > represents a nitrogen atom each independently, R _<10a > -R < _12a > represents a lone pair. Y _{29 to} Y ₃₅ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. When Y < ₂₉ > -Y < ₃₅ > is a carbon atom, R < ₄₁ > -R < ₄₇ > represents a hydrogen atom or a substituent each independently. When Y < ₂₉ > -Y < ₃₅ > is a nitrogen atom, R < ₄₁ > -R < ₄₇ > represents an unshared electron pair each independently. Y _{36 to} Y ₄₂ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₃₆ to Y ₄₂ is a carbon _atom, R 48 _{to R 54} each independently represent a hydrogen atom or a substituent. When Y < ₃₆ > -Y < ₄₂ > is a nitrogen atom, R < ₄₈ > -R < ₅₄ > represents an unshared electron pair each independently. Z ₁₆ to Z ₂₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. R ₅₅ to R ₅₈ each independently represents any of a hydrogen atom, a substituent or an unshared electron pair. ] The compound having a structure represented by the general formula (3) has a structure represented by the following general formula (5),
The transparent electrode according to claim 5, wherein the compound having the structure represented by the general formula (4) has a structure represented by the following general formula (6).

[In General Formula (5), X < ₁₃ > -X < ₁₅ > represents a carbon atom or a nitrogen atom each independently. When X < ₁₃ > -X < ₁₅ > represents a carbon atom each independently, R _<13a > -R < _15a > represents a hydrogen atom. When X < ₁₃ > -X < ₁₅ > represents a nitrogen atom each independently, R _<13a > -R < _15a > represents a lone pair. Y _{43 to} Y ₄₉ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₄₃ to Y ₄₉ is a carbon _atom, R 59 _{to R 65} each independently represent a hydrogen atom or a substituent. If Y ₄₃ to Y ₄₉ is a nitrogen _atom, R 59 _{to R 65} each independently represent a non-covalent electron pair. Y _{50 to} Y ₅₆ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₀ to Y ₅₆ is a carbon _atom, R 66 _{to R 72} each independently represent a hydrogen atom or a substituent. If Y ₅₀ to Y ₅₆ is a nitrogen _atom, R 66 _{to R 72} each independently represent a non-covalent electron pair. R ₇₃ and R ₇₄ each independently represent either a hydrogen atom or a substituent. ]

[In General Formula (6), X _{16 to} X ₁₈ each independently represents a carbon atom or a nitrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a carbon _atom, R 16a _{to R 18a} represents a hydrogen atom. X ₁₆ to X ₁₈ are each independently, it may represent a nitrogen _atom, R 16a _{to R 18a} represents a lone pair. Y _{57 to} Y ₆₃ each independently represent a carbon atom or a nitrogen atom, and at least one represents a nitrogen atom. If Y ₅₇ to Y ₆₃ is a carbon _atom, R 75 _{to R 81} each independently represent a hydrogen atom or a substituent. If Y ₅₇ to Y ₆₃ is a nitrogen _atom, R 75 _{to R 81} each independently represent a non-covalent electron pair. Y ₆₄ to Y ₇₀ each independently represents a carbon atom or a nitrogen atom, at least one nitrogen atom. If Y ₆₄ to Y ₇₀ is a carbon _atom, R 82 _{to R 88} each independently represent a hydrogen atom or a substituent. If Y ₆₄ to Y ₇₀ is a nitrogen _atom, R 82 _{to R 88} each independently represent a non-covalent electron pair. R ₈₉ and R ₉₀ each independently represent either a hydrogen atom or a substituent. ] At least two of X _{13 to} X _{15 in} the general formula (5) represent a nitrogen atom, and at least two of X _{16 to} X _{18 in} the general formula (6). Represents a nitrogen atom, The transparent electrode according to claim 6. In the general formula (5), at least one of R _{59 to} R ₇₄ , and in the general formula (6), at least one of R _{75 to} R ₉₀ is a linear substituent or branched. The transparent electrode according to claim 6, wherein the transparent electrode is a substituent. An electronic device comprising the transparent electrode according to any one of claims 1 to 8 . An organic electroluminescence device comprising the transparent electrode according to any one of claims 1 to 8 .

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