JP6003021B2 - Organic electroluminescent device, organic EL module, organic EL display device, and method of manufacturing organic EL lighting - Google Patents

Description

  The present invention relates to an organic electroluminescent element, an organic EL module, an organic EL display device, and organic EL illumination. More specifically, an organic electroluminescent device provided with a scattering layer for improving light extraction efficiency, which has improved dark spot generation and short circuit between the anode and the cathode due to the provision of the scattering layer. The present invention relates to an element, an organic EL module including the organic electroluminescent element, an organic EL display device, and organic EL illumination.

  Since the launch of Kodak's stacked organic electroluminescent device (hereinafter sometimes referred to as “organic EL”) using the vapor deposition method, organic EL displays and organic EL lighting have been actively developed and are now in practical use. It is being done. The organic electroluminescent element has a thin film shape and has features such as small size, light weight, and high luminous efficiency. Therefore, the organic electroluminescent element has great expectations not only for flat display applications but also for illumination applications.

  In addition, due to social demands such as low carbon dioxide emission environmental problems and energy savings in recent years, organic electroluminescent devices are also required to have higher luminous efficiency. With the development of light emitting materials, optical devices with high light extraction efficiency are required. Structures and optical device structures are also being developed.

  An organic electroluminescent element comprises an anode, a cathode and a light emitting layer formed between both electrodes on a glass substrate, and a part of the light generated by energizing both electrodes is a high refractive index anode ( For example, it is reflected to the ITO side at the interface between the transparent electrode such as ITO) and the glass substrate, and the remainder enters the glass substrate. When the light that has passed through the glass substrate is emitted from the glass substrate to the atmosphere, it is further reflected to the inside of the glass substrate at the interface between the glass substrate and the low refractive index air. Finally, only about 20% of the light is reflected on the glass substrate. To the atmosphere.

  Conventionally, in order to improve the light extraction efficiency of an organic electroluminescence device, a scattering layer containing a scatterer is provided between a transparent electrode such as ITO as an anode and a glass substrate, or on the atmosphere side surface of the glass substrate. Attempts have been reported to efficiently guide light from the transparent electrode into the glass substrate or from the glass substrate to the atmosphere.

For example, in Patent Document 1, glass frit (powder) is used as a kneaded ink together with resin, applied onto a glass substrate, fired and heated at a high temperature, thereby melting the glass frit. It has been reported that CO ₂ -derived bubbles having a scattering function are formed in a glass scattering layer by using a CO ₂ gas generated by burning out the resin.

  In addition, in this patent document 1, as a formation method of the organic layer on a transparent electrode, "Here, an organic layer is formed by the combined use of a coating method and a vapor deposition method. For example, one or more layers with an organic layer are formed. If the layer is formed by the coating method, the other layers are formed by the vapor deposition method.If the layer above the layer formed by the coating method is formed by the vapor deposition method, before forming the organic layer by the vapor deposition method, Further, the organic layer may be formed only by a coating method or a vapor deposition method only, and a specific method for forming a hole injection layer and a hole transport layer is described. There is no mention of.

If it is the technique which uses the bubble described in patent document 1 as the scatterer of a scattering layer, there exists the following advantages.
(1) In forming the scattering layer, it is not necessary to add a scatterer such as transparent inorganic particles, and if bubbles derived from CO ₂ are used as the scatterer, the stability over time of the scatterer and the scattering layer itself is secured. As a result, deterioration of the organic electroluminescent element can be prevented.
(2) It is possible to easily generate CO ₂ -derived bubbles, that is, scatterers necessary for light extraction.
(3) CO ₂ -derived bubbles have a large difference in refractive index from the glass component forming the scattering layer, and thus have a large light diffusion effect. Also, the bubbles themselves have high transparency, and therefore backscattering is small. The light extraction efficiency from the transparent electrode to the scattering layer is high.

International Publication 2009/060916 Pamphlet

However, the technique of Patent Document 1 has the following problems.
(1) When bubbles are generated with the ink forming the scattering layer, the bubbles are unevenly distributed on the glass substrate side, so that the bubbles cannot act strongly on the light captured near the transparent electrode. Therefore, the light from the transparent electrode side cannot be efficiently taken into the glass substrate.
(2) The surface flatness of the formed scattering layer is poor due to the shrinkage of the glass component derived from the ink in the cooling process during the formation of the scattering layer and the influence of bubbles near the surface. In such an organic electroluminescent device in which an organic layer is laminated on the scattering layer by a normal vacuum vapor deposition method, a dark spot or a defect such as a short circuit is easily generated between the transparent electrode and the cathode.

  The present invention relates to an organic electroluminescent device provided with a scattering layer to improve light extraction efficiency, and an organic electric field in which the generation of dark spots and short circuit between the anode and the cathode due to the provision of the scattering layer is improved. A light emitting element, and further, an organic electroluminescent element that further improves the light extraction efficiency by controlling the distribution of scatterers in the scattering layer, an organic EL module including the organic electroluminescent element, an organic EL display device, and It is an object to provide organic EL lighting.

  As a result of intensive studies to solve the above problems, the present inventors have found that a hole injection layer and / or a hole transport layer close to the scattering layer (hereinafter referred to as a “underlayer” together with a hole injection layer and a hole transport layer). ) Is formed by a wet film formation method (hereinafter also referred to as “coating method”), whereby the underlayer is formed so as to follow the irregularities on the surface of the scattering layer, Demonstrating the function as a protective film, as a result, it is possible to prevent a film formation defect of each layer formed on the underlayer, and to realize a long-life organic electroluminescence element free from dark spots and short-circuit problems, In addition, by adjusting the distribution of scatterers in the scattering layer, light can be guided more effectively from the transparent electrode to the glass substrate, and the light extraction efficiency can be further improved. I found it.

  The present invention has been achieved on the basis of such findings, and the gist thereof is as follows.

[1] In the method of manufacturing an organic electroluminescent device having a laminate including a scattering layer, a hole injection layer, a hole transport layer, and a light emitting layer, the scattering layer is made of high refractive index glass and bubbles as a scatterer. is configured, and the hole injection layer and / or hole transporting layer to a method of fabricating an organic light emitting device you formed by a wet film-forming method, the organic electroluminescent device, supports the laminate glass A substrate, the scattering layer is formed adjacent to the glass substrate, a transparent electrode is further stacked adjacent to the surface of the scattering layer opposite to the glass substrate side, and The method of manufacturing an organic electroluminescent element (provided that “the number of scatterers”), wherein the number density of the scatterers in the thickness direction of the scattering layer increases toward the transparent electrode in the vicinity of the transparent electrode. "Number density" means "scatterers per unit volume of scattering layer" (Number of pieces / m ³ ) ”.)

[2] The hole injection layer and the hole transport layer, a method of manufacturing an organic electroluminescent device according to be formed using a polyaryl amino resin thermal insoluble characterized Rukoto [1].

[3] The difference between the number density of the scatterers in the central portion in the thickness direction of the scattering layer and the number density of the scatterers on the interface side of both of the scattering layers is 30% or less. The method for producing an organic electroluminescence device according to [1] or [2] (where “number density of scatterers” is “number of scatterers per unit volume of scattering layer (pieces / m ³ )”). ).

[4] An organic electroluminescent device is manufactured by the method for manufacturing an organic electroluminescent device according to any one of [1] to [3], and a plurality of the organic electroluminescent devices are crossed in the stacking direction and the crossing direction of the stack. a manufacturing method of an organic EL module that arranged parallel to, a method of manufacturing an organic EL module, wherein a light-emitting layer included in the organic electroluminescent device of said plurality of comprises a respective specific emission spectrum.

[5] An organic electroluminescence device is produced by the method for producing an organic electroluminescence device according to any one of [1] to [3], and an organic EL display device is produced using the organic electroluminescence device. A method for manufacturing an organic EL display device.

[6] [1] to features that you produce organic EL illumination using to prepare an organic electroluminescent device, the organic electroluminescent device by the manufacturing method of the organic electroluminescent device according to any one of [3] The manufacturing method of organic EL lighting.

[7] [4] to produce an organic EL module by the production method of the organic EL module according to manufacturing method of the organic EL lighting which is characterized that you produce organic EL illumination using the organic EL module.

  According to the present invention, the hole injection layer and / or the hole transport layer (underlying layer) close to the scattering layer is formed by a wet film forming method so that the underlayer follows the irregularities on the surface of the scattering layer. To achieve a long-life organic electroluminescence device free from problems of dark spots and short-circuits by preventing film formation defects in each layer formed on the underlying layer as a result. Can do. Further, by adjusting the distribution of the scatterers in the scattering layer, light can be guided more effectively from the transparent electrode to the glass substrate, and the light extraction efficiency can be further improved.

It is a schematic diagram of the cross section which shows the structural example of the organic electroluminescent element of this invention.

  Embodiments of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the invention.

[1] Organic electroluminescent device The organic electroluminescent device of the present invention is an organic electroluminescent device having a laminate including a scattering layer, a hole injection layer, a hole transport layer, and a light emitting layer. The body is a bubble or a glass particle, and the hole injection layer and / or the hole transport layer is formed by a wet film forming method.

  In the present invention, the wet film forming method includes, for example, a spin coating method, a dip coating method, a die coating method, a bar coating method, a blade coating method, a roll coating method, a spray coating method, a capillary coating method, a nozzle coating method, an inkjet method. This method is a wet film formation method such as a printing method, a screen printing method, a gravure printing method, or a flexographic printing method. Among these film forming methods, a spin coating method, a spray coating method, and an ink jet method are preferable. This is because the liquid property unique to the composition for wet film formation used in the organic electroluminescence device is met.

Below, with reference to FIG. 1 which is an example of embodiment of the organic electroluminescent element of this invention, the structure of each layer and its formation method are demonstrated.
FIG. 1 is a schematic cross-sectional view showing a structural example of an organic electroluminescent device 20 according to the present invention. In FIG. 1, 1 is a scattering layer, 2 is an anode, 3 is a hole injection layer, and 4 is a hole transport layer. Reference numeral 5 denotes a light emitting layer, 6 denotes a hole blocking layer, 7 denotes an electron transport layer, 8 denotes an electron injection layer, 9 denotes a cathode, and 10 denotes a substrate.

[substrate]
The substrate 10 serves as a support for the organic electroluminescent element, and a material having a high visible light transmittance, such as a glass substrate, is mainly used. Specifically, a plastic substrate is used as the material having a high transmittance in addition to the glass substrate. Examples of the material of the glass substrate include inorganic glass such as alkali glass, non-alkali glass, and quartz glass. Examples of the material for the plastic substrate include polyester, polycarbonate, polyether, polysulfone, polymethacrylate, polyethersulfone, polyvinyl alcohol, fluorine-containing polymers such as polyvinylidene fluoride and polyvinyl fluoride. Note that in order to prevent moisture from permeating through the substrate, the plastic substrate may have a barrier property. For this reason, a method of providing a gas barrier property by providing a dense silicon oxide film or the like on at least one surface of the plastic substrate is also a preferable method.

As a glass substrate, the thing which does not contain Pb from the point of environmental protection is preferable. Moreover, it is preferable that the refractive index of the glass substrate used for this invention is 1-2.5, especially 1.4-2.2. When the refractive index is not less than the above lower limit, total reflection at the interface between the scattering layer and the glass substrate is difficult to occur, and the light transmittance from the scattering layer to the glass substrate is increased. The greater the refractive index of the glass substrate, the better the light transmittance from the scattering layer to the glass substrate. However, since the refractive index is below the above upper limit, total reflection at the interface between the glass substrate and the atmosphere is less likely to occur. The transmittance of light from the glass substrate to the atmosphere can be increased.
In order to suppress total reflection at the interface between the scattering layer and the glass substrate, the interface between the scattering layer and the glass substrate is made non-uniform, or one or both sides of the interface between the scattering layer and the glass substrate are roughened. It is also effective to have a non-uniform interface, such as infiltrating a refractive index oil or adhesive.

  The thickness of a preferable glass substrate is 0.1-100 mm, More preferably, it is 0.2-50 mm, More preferably, it is 0.3-10 mm. When the thickness of the glass substrate is not more than the above upper limit, a decrease in light transmittance can be suppressed, and when it is not less than the above lower limit, physical strength can be maintained and cracking of the substrate can be prevented.

Incidentally, in order to produce the scattering layer with glass frit, the thermal expansion coefficient of the glass substrate is not less than 50 × 10 ⁻⁷ / ° C., preferably not less than 70 × 10 ⁻⁷ / ° C. More preferably, it is 80 × 10 ⁻⁷ / ° C. or higher. Furthermore, the average thermal expansion coefficient at 100 to 400 ° C. of the scattering layer is 70 × 10 ^{−7 to} 95 × 10 ⁻⁷ (° C. ⁻¹ ), and the glass transition temperature is 450 to 550 ° C. preferable.

[Scattering layer]
The scattering layer is formed to improve the light extraction efficiency of the organic electroluminescent element.

<Refractive index>
The refractive index of the scattering layer is preferably equal to or lower than the refractive index of the transparent electrode as the anode formed thereon, and the refractive index higher than the refractive index of the glass substrate is the interface between the transparent electrode and the scattering layer and the scattering layer. This is preferable because total reflection at the interface between the glass substrate and the glass substrate is suppressed.
In the present invention, by adjusting the difference between the refractive index of the base layer constituting the scattering layer and the refractive index of the scatterers distributed in the base layer, the refractive index of the scattering layer is changed to the refractive index of the transparent electrode. It can be equivalent or low.

The refractive index of the scatterer and the base layer may be high, but the difference in refractive index (Δn) is preferably 0.2 or more at least in a part of the emission spectrum range of the light emitting layer. In order to obtain sufficient scattering characteristics, the difference in refractive index (Δn) should be 0.2 or more over the entire emission spectrum range (430 nm to 650 nm) or the entire visible wavelength range (360 nm to 830 nm). More preferred.

  In order to obtain the maximum refractive index difference, the high light transmittance material (hereinafter sometimes referred to as “base material”) constituting the base layer of the scattering layer is a high refractive index glass, and the scatterer is a gas. It is desirable to have a configuration of an object, that is, a bubble.

In this invention, since the refractive index of a base material may be smaller than the refractive index of a transparent electrode, the freedom degree in selection of the material which can be used becomes high. However, also in this case, since it is desirable that the refractive index of the base material be as high as possible, it is preferable that the base material be glass having a high refractive index. As a high refractive index glass component, as a network former, one or more components selected from P ₂ O ₅ , SiO ₂ , B ₂ O ₃ , Ge ₂ O, TeO ₂ are used as a high refractive index component. , TiO ₂ , Nb ₂ O ₅ , WO ₃ , Bi ₂ O ₃ , La ₂ O ₃ , Gd ₂ O ₃ , Y ₂ O ₃ , ZrO ₂ , ZnO, BaO, PbO, Sb ₂ O ₃ Alternatively, a high refractive index glass containing two or more kinds of components can be used. In addition, in order to adjust the characteristics of the glass, alkali oxides, alkaline earth oxides, fluorides, and the like may be used as long as the physical properties required for the refractive index are not impaired. Specific glass systems include B ₂ O ₃ —ZnO—La ₂ O ₃ system, P ₂ O ₅ —B ₂ O ₃ —R ′ ₂ O—R ″ O—TiO ₂ —Nb ₂ O ₅ —WO _3- Bi ₂ O ₃ system, TeO ₂ —ZnO system, B ₂ O ₃ —Bi ₂ O ₃ system, SiO ₂ —Bi ₂ O ₃ system, SiO ₂ —ZnO system, B ₂ O ₃ —ZnO system, P ₂ Examples thereof include an O ₅ —ZnO system. Here, R ′ represents an alkali metal element, and R ″ represents an alkaline earth metal element. In addition, the above is an example, and if it is the structure which satisfy | fills said conditions, it will not be limited to this example.

  By giving the base material a specific transmittance spectrum, the color of light emission can be changed. As the colorant, known ones such as transition metal oxides, rare earth metal oxides and metal colloids can be used alone or in combination.

<Scatterer>
Examples of the scatterer in the scattering layer include bubbles or glass particles. Bubbles are formed by gas generation during the formation of the scattering layer, as will be described later. The glass grains are unmelted nuclei of the glass frit that remains without being melted in the heating and firing step when forming the scattering layer.

  The particle size of the scatterer is in the range of 0.1 to 10 μm, particularly 0.2 to 8 μm, and the average particle size is preferably 0.5 to 7 μm, particularly 1 to 5 μm.

  When the particle size of the scatterer is not less than the above lower limit, a high light scattering effect is obtained, and when the particle size is not more than the above upper limit, the scatterer is prevented from protruding to the surface of the scattering layer, and high flatness is maintained.

  Here, the particle size of the scatterer is the value of the diameter of the scatterer particles measured by electron microscope observation, and the average particle size is the number average value thereof.

The distribution of scatterers in the scattering layer is preferably as follows.
(1) In the thickness direction of the scattering layer, the number density of the scatterers decreases in the vicinity of the transparent electrode of the anode toward the transparent electrode.
(2) In the thickness direction of the scattering layer, the number density of the scatterers increases toward the transparent electrode near the transparent electrode of the scatterer.

Here, the number density is the number of scatterers (units / m ³ ) per unit volume of the scattering layer.

  Further, the vicinity of the transparent electrode of the anode refers to a portion from the transparent electrode side in the scattering layer to 1/3 in the thickness direction.

  A high light scattering effect is obtained with the scatterer distribution of (1) above.

  With the scatterer distribution of (2) above, in addition to a high light scattering effect, light constrained by the transparent electrode can be guided into the scattering layer, and further improvement in light extraction efficiency can be expected.

  However, the scatterers may be uniformly distributed in the scattering layer. In this case, in addition to the high light scattering and the effect of introducing the light constrained by the transparent electrode into the scattering layer, it is taken into the scattering layer. The light transmitted through the scatterer particles and efficiently guided into the glass substrate enables high light extraction efficiency to be realized.

In any case, the difference between the number density of the scatterers in the central portion in the thickness direction of the scattering layer and the number density of the scatterers on both interface sides of the scattering layer is 30% or less, that is, in the thickness direction of the scattering layer. The absolute value of the difference (A−B) between the number density A (number / m ³ ) of scatterers in the central portion and the number density B (number / m ³ ) of scatterers on the interface side of both scattering layers is A And B is preferably 30% or less of the larger value from the viewpoint of light extraction efficiency. Here, the central portion in the thickness direction of the scattering layer refers to a portion of 1/3 to 2/3 in the thickness direction from the transparent electrode side of the scattering layer.

<Surface roughness (Ra)>
The surface of the scattering layer (the surface on the transparent electrode forming side that is the anode) is preferably smooth, and the arithmetic average roughness (surface roughness: Ra) defined in JIS B0610-1994 between 10 μm is 30 nm or less. Preferably, it is 10 nm or less.
Here, “between 10 μm” on the surface of the scattering layer refers to a distance between two points arbitrarily selected on the surface of the scattering layer.

<Thickness of scattering layer>
The thickness of the scattering layer according to the present invention is preferably 2 to 100 μm, particularly preferably 5 to 70 μm.
When the thickness of the scattering layer is not less than the above lower limit, the light scattering efficiency is increased, and when it is not more than the above upper limit, cracking of the scattering layer can be suppressed.

<Method for forming scattering layer>
The scattering layer is formed by coating and baking. In particular, from the viewpoint of uniformly and rapidly forming a 10-100 μm thick, large-area scattering layer, a method of forming glass by frit paste is preferable.

  Here, the frit paste refers to a glass powder dispersed in a resin, a solvent, a filler or the like. The scattering layer can be coated with the glass layer by patterning and baking the frit paste using a pattern forming technique such as screen printing.

In order to suppress thermal deformation of the glass substrate when forming the scattering layer by the frit paste method, the glass softening point (Ts) of the scattering layer is lower than the strain point (SP) of the glass constituting the substrate, and thermal expansion is achieved. It is desirable that the difference in coefficient α is small. The difference between the softening point and the strain point is preferably 30 ° C. or higher, and more preferably 50 ° C. or higher. In addition, the difference in thermal tension between the scattering layer and the glass constituting the substrate is preferably ± 10 × 10 ⁻⁷ (1 / K) or less, and is ± 5 × 10 ⁻⁷ (1 / K) or less. It is more preferable.

  The technical outline of frit paste is shown below.

(Frit paste material)
<Glass powder>
The particle size of the glass powder used is usually 1 μm to 10 μm. In order to control the thermal expansion of the fired film, a filler may be added. Specifically, zircon, silica, alumina or the like is used as the filler, and the particle size thereof is 0.1 μm to 20 μm.

The glass material will be described below.
In the present invention, the scattering _layer, P ₂ O 5: _{0~30 mol%, B} 2 O 3: _0~14 mol%, the total amount of Li ₂ O, Na ₂ O and _{K 2} O: 0 to 20 mol%, Bi ₂ O ₃ : 10 to 20 mol%, TiO ₂ : 3 to 15 mol%, Nb ₂ O ₅ : 0 to 20 mol%, WO ₃ : 0 to 15 mol%, and the total amount of the above components is What is 90 mol% or more is also used suitably.

The glass composition for forming the scattering layer is not particularly limited as long as the desired scattering characteristics can be obtained and frit paste can be fired, but in order to maximize the extraction efficiency, for example, P ₂ O ₅ is used. A system containing one or more components of Nb ₂ O ₅ , Bi ₂ O ₃ , TiO ₂ , WO ₃ , B ₂ O ₃ , ZnO and La ₂ O ₃ as essential components A system containing one or more components of ₂ O ₅ , ZrO ₂ , Ta ₂ O ₅ , WO ₃ , a system containing SiO ₂ as an essential component, and containing one or more components of Nb ₂ O ₅ , TiO ₂ , Bi ₂ O ₃ as a main component, and a system containing SiO ₂ , B ₂ O ₃ or the like as a network forming component.

The glass composition for forming the scattering layer is not particularly limited as long as the desired scattering characteristics can be obtained and frit paste can be fired, but in order to maximize the extraction efficiency, for example, P ₂ O ₅ is used. Nb ₂ O ₅ , Bi ₂ O ₃ , TiO ₂ , a system containing one or more components of WO ₃ , B ₂ O ₃ , La ₂ O ₃ as essential components, Nb ₂ O ₅ , ZrO ₂ , Ta ₂ O ₅ , a system containing one or more components of WO ₃ , SiO ₂ as an essential component, Nb ₂ O ₅ , a system containing one or more components of TiO ₂ , Bi ₂ O ₃ as a main component, Examples of the glass forming aid include systems containing SiO ₂ , B ₂ O _{3 and the} like.

_[1] include _{P 2 O 5, Nb 2 O} 5, Bi 2 O 3, TiO 2, WO 3, scattering layer containing more than one component of, in mole percent _notation, P ₂ O 5 15 to 30% SiO ₂ 0-15%, B ₂ O ₃ 0-18%, Nb ₂ O ₅ 5-40%, TiO ₂ 0-15%, WO ₃ 0-50%, Bi ₂ O ₃ 0-30%, _{, Nb 2 O 5 + TiO 2} + WO 3 + Bi 2 O 3 20~60%, Li 2 O0~20%, Na 2 O0~20%, K 2 O0~20%, provided that _{Li 2 O + Na 2 O +} K 2 O5~40% A glass having a composition range of MgO 0 to 10%, CaO 0 to 10%, SrO 0 to 10%, BaO 0 to 20%, ZnO 0 to 20%, Ta ₂ O ₅ 0 to 10% is preferable.

  The effect of each component is as follows in terms of mol%.

P ₂ O ₅ is an essential component for forming and vitrifying the glass-based skeleton. In order to obtain glass without increasing the devitrification property of the glass, 15% or more is preferable, and 18% or more is more preferable. . In order to prevent a decrease in refractive index, the content is preferably 30% or less, and more preferably 28% or less.

B ₂ O ₃ is an optional component that improves devitrification resistance and decreases the coefficient of thermal expansion by adding it to the glass. However, in order to suppress a decrease in refractive index, the content is 18% or less. Preferably, 15% or less is more preferable.

SiO ₂ is an optional component that stabilizes the glass by adding a trace amount and improves devitrification resistance. However, in order to suppress a decrease in the refractive index, the content is preferably 15% or less, and 10% The following is more preferable, and 8% or less is particularly preferable.

Nb ₂ O ₅ is an essential component that simultaneously has the effects of improving the refractive index and enhancing weather resistance. Therefore, the content is preferably 5% or more, and more preferably 8% or more. On the other hand, in order to suppress devitrification and stably obtain glass, the content is preferably 40% or less, and more preferably 35% or less.

TiO ₂ is an optional component that improves the refractive index, but the content is preferably 15% or less in order to suppress the coloring of the glass, reduce the loss in the scattering layer, and improve the light extraction efficiency, 13% More preferably, it is as follows.

WO ₃ is an optional component that improves the refractive index, lowers the glass transition temperature, and lowers the firing temperature. However, in order to prevent the coloring of the glass and maintain the light extraction efficiency, its content is 50% or less. Is preferable, and 45% or less is more preferable.

Bi ₂ O ₃ is a component that improves the refractive index and can be introduced into the glass in a relatively large amount while maintaining the stability of the glass, but in order to suppress a decrease in transmittance due to the coloring of the glass, The content is preferably 30% or less, and more preferably 25% or less.

In order to make the refractive index higher than a desired value, one or more of Nb ₂ O ₅ , TiO ₂ , WO ₃ and Bi ₂ O ₃ must be included. Specifically, the total amount of (Nb ₂ O ₅ + TiO ₂ + WO ₃ + Bi ₂ O ₃ ) is preferably 20% or more, and more preferably 25% or more. On the other hand, in order to suppress coloring and devitrification, the total amount of these components is preferably 60% or less, and more preferably 55% or less.

Ta ₂ O ₅ is an optional component that improves the refractive index, but its content is preferably 10% or less, and more preferably 5% or less, in order to suppress a decrease in devitrification resistance and an increase in price.

Alkali metal oxides (R ₂ O) such as Li ₂ O, Na ₂ O, K ₂ O have the effect of improving the meltability and lowering the glass transition temperature, and at the same time, increasing the affinity with the glass substrate. And has the effect of increasing the adhesion. Therefore, it is desirable to contain one or more of these. The total amount of Li ₂ O + Na ₂ O + K ₂ O is desirably 5% or more, and more preferably 10% or more. Further, in order to maintain the stability of the glass and maintain the refractive index of the glass to improve the desired light extraction efficiency, the total content thereof is preferably 40% or less, and 35% or less. It is more preferable.

Li ₂ O is a component for lowering the glass transition temperature and improving the solubility. However, in order to suppress devitrification and obtain a homogeneous glass, the thermal expansion coefficient is suppressed, In order to reduce the difference in expansion coefficient and prevent a decrease in the refractive index to improve the desired light extraction efficiency, the content is desirably 20% or less, and more desirably 15% or less.

Na 2 _O, but neither _K 2 _O is an optional component for improving the meltability, in order to obtain the desired light-extraction efficiency by preventing a decrease in the refractive index, it is the content is 20% or less, respectively Preferably, it is 15% or less.

  ZnO is a component that improves the refractive index and lowers the glass transition temperature, but in order to reduce the devitrification of the glass and obtain a homogeneous glass, its content is preferably 20% or less, 18 % Or less is more preferable.

  BaO is a component that improves the refractive index and at the same time improves the solubility, but in order to maintain the stability of the glass, its content is preferably 20% or less, and 18% or less. Is more preferable.

  MgO, CaO, and SrO are optional components that improve the meltability, but are preferably 10% or less, and more preferably 8% or less, in order to prevent a decrease in the refractive index.

  In order to obtain a glass having a high refractive index and stability, the total amount of the above components is preferably 90% or more, more preferably 93% or more, and further preferably 95% or more.

In addition to the components described above, a small amount of a refining agent, a vitrification promoting component, a refractive index adjusting component, a wavelength converting component, or the like may be added within a range that does not impair the required glass properties. Specifically, Sb ₂ O ₃ and SnO ₂ are exemplified as the fining agent, GeO ₂ , Ga ₂ O ₃ , In ₂ O ₃ as the vitrification promoting component, ZrO ₂ as the refractive index adjusting component, Examples of Y ₂ O ₃ , La ₂ O ₃ , Gd ₂ O ₃ , Yb ₂ O ₃ , and wavelength conversion component include rare earth components such as CeO ₂ , Eu ₂ O ₃ , and Er ₂ O ₃ .

[2] The scattering layer containing B ₂ O ₃ , La ₂ O ₃ as essential components, and containing one or more components of Nb ₂ O ₅ , ZrO ₂ , Ta ₂ O ₅ , WO ₃ is expressed in mol%. _{B 2 O 3 20~60%, SiO} 2 0~20%, Li 2 O0~20%, Na 2 O0~10%, K 2 O0~10%, ZnO5~50%, La 2 O 3 5~25% Gd ₂ O ₃ 0-25%, Y ₂ O ₃ 0-20%, Yb ₂ O ₃ 0-20%, but La ₂ O ₃ + Gd ₂ O ₃ + Y ₂ O ₃ + Yb ₂ O ₃ 5% -30 %, ZrO ₂ 0-15%, Ta ₂ O ₅ 0-20%, Nb ₂ O ₅ 0-20%, WO ₃ 0-20%, Bi ₂ O ₃ 0-20%, BaO 0-20% The glass is preferred.

  The effect of each component is as follows in terms of mol%.

B ₂ O ₃ is a network forming oxide and is an essential component in this glass system. While forming glass, in order to prevent the fall of devitrification resistance of glass, the content is preferably 20% or more, and more preferably 25% or more. On the other hand, in order to prevent a decrease in refractive index and weather resistance, the content is 60% or less, more preferably 55% or less.

SiO ₂ is a component that improves the stability of the glass when added to the glass of this system, but its content is 20% or less in order to prevent a decrease in the refractive index and an increase in the glass transition temperature. It is preferable that it is 18% or less.

Li ₂ O is a component that lowers the glass transition temperature, but in order to prevent a decrease in the devitrification resistance of the glass, its content is preferably 20% or less, and 18% or less. More preferred.

Na ₂ O and K ₂ O improve solubility, but in order to maintain devitrification resistance and refractive index, their contents are each preferably 10% or less, more preferably 8% or less. preferable.

  ZnO is an essential component that improves the refractive index of the glass and lowers the glass transition temperature. Therefore, the content is preferably 5% or more, and more preferably 7% or more. On the other hand, in order to maintain the devitrification resistance and obtain a homogeneous glass, the content is preferably 50% or less, and more preferably 45% or less.

La ₂ O ₃ is an essential component that achieves a high refractive index and improves weather resistance when introduced into B ₂ O ₃ glass. Therefore, the content is preferably 5% or more, and more preferably 7% or more. On the other hand, in order to lower the glass transition temperature and maintain the devitrification resistance of the glass to obtain a homogeneous glass, the content is preferably 25% or less, and more preferably 22% or less.

Gd ₂ O ₃ is a component that achieves a high refractive index and improves weather resistance when introduced into B ₂ O ₃ glass, and improves the stability of the glass by coexisting with La ₂ O ₃ , In order to ensure the stability of the glass, the content is preferably 25% or less, and more preferably 22% or less.

Y ₂ O ₃ and Yb ₂ O ₃ achieve a high refractive index, improve the weather resistance when introduced into B ₂ O ₃ glass, and improve the stability of the glass by coexisting with La ₂ O ₃ . Although it is a component, in order to maintain the stability of the glass, the content thereof is preferably 20% or less, and more preferably 18% or less.

Rare earth oxides such as La ₂ O ₃ , Gd ₂ O ₃ , Y ₂ O ₃ and Yb ₂ O ₃ are essential components for achieving a high refractive index and improving the weather resistance of glass. The total amount of these components, La ₂ O ₃ + Gd ₂ O ₃ + Y ₂ O ₃ + Yb ₂ O ₃ is preferably 5% or more, and more preferably 8% or more. However, in order to maintain the devitrification resistance of the glass and obtain a homogeneous glass, the total amount of these components is preferably 30% or less, and more preferably 25% or less.

ZrO ₂ is a component for improving the refractive index, but its content is preferably 15% or less in order to suppress a decrease in devitrification resistance and an excessive increase in liquidus temperature, and is preferably 10% or less. It is more preferable that

Ta ₂ O ₅ is a component for improving the refractive index, but in order to suppress a decrease in devitrification resistance and an excessive increase in the liquidus temperature, its content is preferably 20% or less, 15 % Or less is more preferable.

Nb ₂ O ₅ is a component for improving the refractive index, but its content is preferably 20% or less in order to suppress a decrease in devitrification resistance and an excessive increase in liquidus temperature. % Or less is more preferable.

WO ₃ is a component for improving the refractive index. However, in order to suppress a decrease in devitrification resistance and an excessive increase in the liquidus temperature, the content is preferably 20% or less, and 15% or less. It is more preferable that

Bi ₂ O ₃ is a component for improving the refractive index, but its content is 20 in order to prevent devitrification resistance reduction, coloration of the glass and the resulting reduction in transmittance and maintain the extraction efficiency. % Or less is preferable, and 15% or less is more preferable.

  BaO is a component that improves the refractive index, but in order to ensure devitrification resistance, its content is preferably 20% or less, more preferably 15% or less.

The total amount of the components described above is preferably 90% or more, and more preferably 95% or more. Even components other than those described above may be added within the range not impairing the effects of the present invention for the purpose of clarifying and improving solubility. Examples of such components include Sb ₂ O ₃ , SnO ₂ , MgO, CaO, SrO, GeO ₂ , Ga ₂ O ₃ , In ₂ O ₃ , and fluorine.

[3] The scattering layer containing SiO ₂ as an essential component and containing one or more components of Nb ₂ O ₅ , TiO ₂ , and Bi ₂ O ₃ is expressed in terms of mol%, SiO ₂ 20 to 50%, B ₂ O. _{3 0~20%, Nb 2 O 5} 1~20%, TiO 2 1~20%, Bi 2 O 3 0~15%, ZrO 2 0~15%, Nb 2 O 5 + TiO 2 + Bi 2 O 3 + ZrO 2 _{5~40%, Li 2 O0~40%,} Na 2 O0~30%, K 2 O0~30%, Li 2 O + Na 2 O + K 2 O1~40%, MgO0~20%, CaO0~20%, SrO0~20 %, BaO 0 to 20%, ZnO 0 to 20% composition range glass is preferable.

  The effect of each component is as follows in terms of mol%.

SiO ₂ is an essential component that functions as a network former for forming glass, and is preferably 20% or more, and more preferably 22% or more in order to form glass. Further, it is preferable in order to suppress crystallization of SiO ₂ is 50% or less.

B ₂ O ₃ helps to form glass by adding a relatively small amount together with SiO ₂ to reduce devitrification, but in order to prevent a decrease in refractive index, its content is preferably 20% or less, More preferably, it is 18% or less.

Nb ₂ O ₅ is an essential component for improving the refractive index, and the content thereof is preferably 1% or more, and more preferably 3% or more. On the other hand, in order to maintain the devitrification resistance of the glass and obtain a homogeneous glass, its content is desirably 20% or less, and more desirably 18% or less.

TiO ₂ is an essential component for improving the refractive index, and its content is preferably 1% or more, and more preferably 3% or more. On the other hand, in order to maintain the devitrification resistance of the glass to obtain a homogeneous glass, to prevent coloring, and to reduce loss due to absorption when light propagates through the scattering layer, the content is 20% or less. It is desirable that it is 18% or less.

Bi ₂ O ₃ is a component for improving the refractive index. However, it maintains the devitrification resistance of the glass to obtain a homogeneous glass, and prevents absorption when light propagates through the scattering layer. In order to reduce the loss due to the above, the content is desirably 15% or less, and more desirably 12% or less.

ZrO ₂ is a component that improves the refractive index without deteriorating the degree of coloring, but in order to maintain the devitrification resistance of the glass and obtain a homogeneous glass, its content should be 15% or less. Preferably, it is 10% or less.

In order to obtain a glass having a high refractive index, Nb ₂ O ₅ + TiO ₂ + Bi ₂ O ₃ + ZrO ₂ is preferably 5% or more, and more preferably 8% or more. On the other hand, this total amount is preferably 40% or less, and more preferably 38% or less, in order to maintain the devitrification resistance of the glass and prevent coloring.

Li ₂ O, Na ₂ O, and K ₂ O are components that improve the solubility and lower the glass transition temperature, and further increase the affinity with the glass substrate. Therefore, the total amount Li ₂ O + Na ₂ O + K ₂ O of these components is preferably 1% or more, and more preferably 3% or more. On the other hand, in order to suppress the content of the alkali oxide component, maintain the devitrification resistance of the glass, and obtain a homogeneous glass, this total amount is preferably 40% or less, and 35% or less. It is more preferable.

  BaO is a component that improves the refractive index and at the same time improves the solubility, but in order to maintain the stability of the glass and obtain a homogeneous glass, its content is preferably 20% or less, 15 % Or less is more preferable.

  MgO, CaO, SrO, and ZnO are components that improve the solubility of the glass. If added appropriately, the devitrification resistance of the glass can be reduced, but in order to suppress the devitrification and obtain a homogeneous glass The content thereof is preferably 20% or less, and more preferably 15% or less.

In order to meet the object of the present invention, the total amount of the components described above is desirably 90% or more. In addition, components other than those described above may be added within the range not impairing the effects of the present invention for the purpose of clarifying and improving solubility. Examples of such components include Sb ₂ O ₃ , SnO ₂ , GeO ₂ , Ga ₂ O ₃ , In ₂ O ₃ , WO ₃ , Ta ₂ O ₅ , La ₂ O ₃ , Gd ₂ O ₃ , Y ₂ O. ₃ and Yb ₂ O ₃ .

[4] The scattering layer containing Bi ₂ O ₃ as a main component and containing SiO ₂ , B ₂ O _3, etc. as a glass forming aid is expressed in mol%, Bi ₂ O ₃ 10-50%, B ₂ O ₃ 1-95%, SiO ₂ 0-30%, but B ₂ O ₃ + SiO ₂ 10-40%, P ₂ O ₅ 0-20%, Li ₂ O 0-15%, Na ₂ O 0-15%, K ₂ O 0-15%, TiO ₂ 0-20%, Nb ₂ O ₅ 0-20%, TeO ₂ 0-20%, MgO 0-10%, CaO 0-10%, SrO 0-10%, BaO 0-10%, A glass having a composition range of GeO ₂ 0 to 10% and Ga ₂ O ₃ 0 to 10% is preferable.

  The effect of each component is as follows in terms of mol%.

Bi ₂ O ₃ is an essential component that achieves a high refractive index and stably forms glass even when introduced in a large amount. Therefore, the content is preferably 10% or more, and more preferably 15% or more. On the other hand, in order to prevent the coloring of the glass and the absorption of light thereby to maintain the extraction efficiency and to prevent the devitrification and obtain a homogeneous glass, its content is preferably 50% or less, 45 % Or less is more preferable.

B ₂ O ₃ is an essential component that works as a network former and assists glass formation in a glass containing a large amount of Bi ₂ O ₃ , and its content is preferably 1% or more, and more preferably 3% or more. On the other hand, in order to prevent a decrease in the refractive index of the glass, the content is preferably 95% or less, more preferably 90% or less.

SiO ₂ is a component that works to assist glass formation using Bi ₂ O ₃ as a network former, but in order to prevent a decrease in refractive index and suppress crystallization of SiO ₂ , its content is 30 % Or less, and more preferably 25% or less.

B ₂ O ₃ and SiO _2, for improving the glass formed by combining, total amount thereof is preferably 5% or more, more preferably 10% or more. On the other hand, in order to prevent a decrease in refractive index, the content is preferably 40% or less, and more preferably 38%.

  In addition, when the content of BaO is large, the crucible is eroded and dissolved, so that an expensive erosion-resistant crucible is required and the manufacturing cost is increased.

P ₂ O ₅ is a component that assists in glass formation and suppresses deterioration of the degree of coloring, but is preferably 20% or less, and more preferably 18% or less in order to maintain the refractive index. .

Li ₂ O, Na ₂ O, and K ₂ O are components for improving the glass solubility and further lowering the glass transition temperature. In order to maintain the devitrification resistance of the glass and obtain a homogeneous glass. Further, it is preferably 15% or less, more preferably 13% or less. Further, if the total amount of the above alkali oxide components, too much Li ₂ O + Na ₂ O + K ₂ O, the refractive index is lowered, and the devitrification resistance of the glass is further lowered. In view of the properties, it is preferably 30% or less, and more preferably 25% or less.

TiO ₂ is a component that improves the refractive index, but in order to prevent coloration, maintain devitrification resistance, and obtain a homogeneous glass, its content is preferably 20% or less, 18 % Or less is more preferable.

Nb ₂ O ₅ is a component that improves the refractive index, but in order to maintain the devitrification resistance of the glass and obtain a stable glass, its content is preferably 20% or less, and 18% or less. More preferably it is.

TeO ₂ is a component that improves the refractive index without deteriorating the degree of coloring, but its content is 20% in order to maintain devitrification resistance and prevent coloring when fired after frit formation. Or less, and more preferably 15% or less.

GeO ₂ is a component that improves the stability of the glass while maintaining a relatively high refractive index. However, since it is extremely expensive, its content is preferably 10% or less in order to reduce costs. More preferably, it is 8% or less, and even more preferably not.

Ga ₂ O ₃ is a component that improves the stability of the glass while maintaining a relatively high refractive index. However, since it is extremely expensive, its content is 10% or less in order to reduce costs. Is preferable, it is more preferable that it is 8% or less, and it is still more preferable not to contain.

In order to meet the object of the present invention, the total amount of the components described above is desirably 90% or more, and more preferably 95% or more. Even components other than those described above may be added within the range not impairing the effects of the present invention for purposes such as clarifying, improving solubility, and adjusting the refractive index. Examples of such components include Sb ₂ O ₃ , SnO ₂ , In ₂ O ₃ , ZrO ₂ , Ta ₂ O ₅ , WO ₃ , La ₂ O ₃ , Gd ₂ O ₃ , Y ₂ O ₃ , Yb ₂ O. ₃ and Al ₂ O ₃ .

In all glass systems used as the scattering layer in the present invention, As ₂ O ₃ , PbO, CdO, ThO ₂ , and HgO, which are components that adversely affect the environment, are inevitably mixed as impurities derived from the raw materials. It must not be included except when doing so.

Furthermore, when the refractive index may be low, R ₂ O—RO—BaO—B ₂ O ₃ —SiO ₂ , RO—Al ₂ O ₃ —P ₂ O ₅ , R ₂ O—B ₂ O ₃ — SiO ₂ (R ₂ O is any one of Li ₂ O, Na ₂ O, and K ₂ O, and RO is any one of MgO, CaO, and SrO) can be used.

  Preferred specific examples of the glass composition for forming the scattering layer according to the present invention are shown below, but are not limited thereto. In addition, the numerical value in the following table represents molar ratio.

<resin>
The resin is used to support the glass powder and filler in the coating film after screen printing. Specific examples of the resin include ethyl cellulose, nitrocellulose, acrylic resin, vinyl acetate, butyral resin, melamine resin, alkyd resin, and rosin resin. Examples of the resin used as the main agent include ethyl cellulose and nitrocellulose. Butyral resin, melamine resin, alkyd resin, and rosin resin are usually used as additives for improving the strength of the coating film. The binder removal temperature during firing is 350 ° C. to 400 ° C. for ethyl cellulose and 200 ° C. to 300 ° C. for nitrocellulose.

<solvent>
The solvent is used to dissolve the resin and adjust the frit paste to the viscosity required for printing. Moreover, the solvent to be used is not dried during printing, and is preferably dried quickly in the drying step, and preferably has a boiling point of 200 ° C. to 230 ° C. Two or more solvents may be blended for adjusting the viscosity, solid content ratio, and drying speed.

  Specific examples of the solvent include ether solvents (butyl carbitol (BC), butyl carbitol acetate (BCA), diethylene glycol di-n-butyl ether, dipropylene glycol butyl ether, tripropylene due to the dry compatibility of the paste during screen printing. Glycol butyl ether, butyl cellosolve), alcohol solvents (α-terpineol, pine oil, dawanol), ester solvents (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), phthalate ester solvents (DBP (dibutyl phthalate), DMP (dimethyl phthalate), DOP (dioctyl phthalate)) and the like. Mainly used solvents are α-terpineol and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate). DBP (dibutyl phthalate), DMP (dimethyl phthalate), and DOP (dioctyl phthalate) also function as a plasticizer.

<Others>
In the frit paste, a surfactant may be used for viscosity adjustment and frit dispersion promotion. A silane coupling agent may be used to modify the frit surface.

(Method for forming frit paste film)
<Frit paste>
Prepare the above glass powder and vehicle. Here, the vehicle refers to a mixture of the above resin, solvent, surfactant and the like. Specifically, a resin, a surfactant, and the like are put in a solvent heated to 50 ° C. to 80 ° C., and then allowed to stand for about 4 to 12 hours, and then filtered.

  Next, the glass powder and the vehicle are mixed with a planetary mixer and then uniformly dispersed with three rolls. Thereafter, the mixture is kneaded with a kneader to adjust the viscosity. Usually, the vehicle is 20 to 60% by weight with respect to 40 to 80% by weight of the glass material.

The glass powder used herein, in the particle diameter _{D 10} of 0.2μm or more and it is desirable to use a _{D 90} of at 5μm or less. If the particle size _D90 is 5 μm or less, the uniformity of the surface of the formed scattering layer will be good. On the other hand, if the particle diameter D ₁₀ of 0.2μm or more, lower the existence ratio of the interface, crystals hardly precipitate, loss hardly watermarks preferred.

<printing>
The frit paste prepared as described above is printed using a screen printer. At this time, it is possible to control the film thickness of the frit paste film formed by the screen plate mesh roughness, emulsion thickness, pressing pressure during printing, squeegee pressing amount, and the like. After printing, it is dried in a baking oven.

<Baking>
Next, the printed and dried substrate is baked in a baking furnace. Firing consists of a binder removal process for decomposing and disappearing the resin in the frit paste and a firing process for sintering and softening the glass powder. The binder removal temperature is 350 ° C. to 400 ° C. for ethyl cellulose and 200 ° C. to 300 ° C. for nitrocellulose, and heating is performed in an air atmosphere for 30 minutes to 1 hour. Thereafter, the temperature is raised to sinter and soften the glass. The firing temperature is from the softening temperature to the softening temperature + 20 ° C., and the shape and size of the bubbles remaining inside varies depending on the processing temperature, but the film uniformly applied to the entire surface is fired. It is formed so as to have a uniform bubble distribution over. Then, it cools and a glass layer is formed on a board | substrate. The thickness of the obtained film is 5 μm to 30 μm, but a thicker glass layer can be formed by laminating at the time of printing.

  If a doctor blade printing method or a die coat printing method is used for the printing process as described above, a thicker film can be formed (green sheet printing). For example, when a film is formed on a PET film or the like and then dried, a green sheet is obtained. Next, the green sheet is thermocompression-bonded on the substrate with a roller or the like, and a fired film is obtained through the same firing process as that of the frit paste. The thickness of the obtained film is 50 μm to 400 μm, but a thicker glass film can be formed by stacking green sheets.

In order to form the scattering layer having the scatterer distribution (1), the following method may be employed.
The ink containing the glass frit applied to the glass substrate is subjected to a heat treatment at a temperature 10 to 20 ° C. higher than the softening temperature of the glass frit ink, whereby the glass frit is made into a high-viscosity glass melt. At this time, pyrolytic gas bubbles having a diameter of 0.1 to 10 μm generated by thermal decomposition of the vehicle resin contained in the glass frit ink have a low moving speed in a glass material having a high viscosity. As a result, the bubbles near the transparent electrode in the layer formed by the glass ink move, release the gas into the atmosphere, and disappear, but the bubbles on the opposite side of the transparent electrode were formed by the glass ink. The scatterer distribution of (1) can be formed by remaining in the layer.

Moreover, in order to form the scattering layer having the scatterer distribution of (2), the following method may be employed.
When the glass frit ink layer applied to the glass substrate is baked at a temperature higher than the softening temperature of the ink, the viscosity of the glass frit melt in the layer decreases as the baking temperature increases. Along with this, the moving speed of the bubbles generated in the glass frit ink layer increases, the bubbles having a large diameter move to the surface of the layer, and the gas is discharged into the atmosphere and disappears. At the same time, the difference in the number density of bubbles (that is, scatterers) in the thickness direction of the layer becomes small, and when the temperature becomes higher by 100 ° C. or more than the softening temperature of the ink, the number density of scatterers in the layer is almost constant in the thickness direction It becomes.

  By utilizing such properties of the glass frit ink layer, for example, the steps of applying and baking the glass frit ink described in the method for forming a scatterer having the scatterer distribution in (1) above are repeated to form two layers. The above scattering layers are laminated. Since the scattering layer in the lower layer of the formed multilayer scattering layer has been fired twice, the number density of bubbles is lower than the number density of bubbles in the upper scattering layer. Therefore, the scatterer distribution of (2) is formed by making the thickness of the scattering layer in the upper layer thinner than that of the lower layer.

  In addition, a scattering layer in which scatterers are uniformly dispersed in the scattering layer can be formed by appropriately selecting the thickness of each scattering layer to be laminated, heating conditions, and the like.

Furthermore, in order to form a scattering layer in which scatterers made of glass unmelted nuclei are distributed, the following method may be employed.
When a layer formed of glass frit ink excluding resin components such as a vehicle is baked at a temperature about 10 ° C. higher than the softening point temperature of the glass material, the outside of the glass frit particles melts, but the central portion A glass frit melted layer in an unmelted state is formed.

The scattering layer according to the present invention may also serve as a glass substrate. In this case, a glass substrate having a light scattering function can be produced as follows.
A glass frit ink is applied on a porcelain plate so that the film thickness after drying is 10 to 20 mm, fired to form a scattering layer, and then naturally cooled, the porcelain plate is removed, and a glass substrate made of the scattering layer is formed. . Next, both surfaces of the glass substrate are polished and the thickness is adjusted to obtain a glass substrate having a light scattering function.

<Transmissivity>
With respect to the glass substrate on which the scattering layer is formed, the light transmittance at a wavelength of 610 nm measured by the method described in the Examples section below is preferably 90% or less, particularly preferably 80% or less because of high light scattering efficiency. .

<Flat film>
For the purpose of smoothing the surface of the scattering layer, the scattering layer according to the present invention may be further provided with a flat film by applying a light or thermosetting organic or inorganic coating material on the scattering layer. it can. The thickness of the flat film is preferably 0.001 to 5 μm, more preferably 0.005 to 2 μm, and still more preferably 0.01 to 1 μm.
As a coating material for forming the flat film, Yuka Denshi Co., Ltd. acrylic photo-curing resin UV1000, Osaka Gas Chemical Co., Ltd. thermosetting resin Ogsol 2A200, Dow Corning Co., Ltd. silicon-based thermosetting resin OE-6665A / B. , Nikko Co., Ltd. liquid glass deoscoat G etc. can be mentioned.

[anode]
The anode 2 plays the role of hole injection into the layer on the light emitting layer 5 side.

The anode is required to have a translucency of 80% or more in order to extract the light generated in the light emitting layer 5 to the outside. In addition, a high work function is required to inject many holes. Specifically, ITO, SnO ₂ , ZnO, IZO (Indium Zinc Oxide), AZO (ZnO—Al ₂ O ₃ : zinc oxide doped with aluminum), GZO (ZnO—Ga ₂ O ₃ : gallium doped) Zb oxide), Nb-doped TiO ₂ , Ta-doped TiO _{2 and the} like are used.

The refractive index of the anode is 1.9 to 2.2. Here, when the carrier concentration is increased, the refractive index of ITO can be lowered. In the case of commercially available ITO, SnO ₂ is 10% by weight as a standard. From this, the refractive index of ITO can be lowered by increasing the Sn concentration. However, although the carrier concentration increases with an increase in Sn concentration, there is a decrease in mobility and transmittance, so it is necessary to determine the Sn amount by balancing these. Here, the refractive index of ITO is preferably determined in consideration of the refractive index of the base material constituting the scattering layer and the refractive index of the cathode 9 serving as the reflective electrode. The difference between the refractive index of ITO of the anode 2 and the refractive index of the base material of the scattering layer 1 is preferably 0.2 or less and high.

In general, the anode is often formed by a sputtering method, a vacuum deposition method, a wet coating method, or the like.
The anode usually has a single-layer structure, but it can also have a laminated structure composed of a plurality of materials if desired.

  The thickness of the anode is usually 10 to 500 nm, preferably 70 to 150 nm. When the thickness of the anode is not less than the above lower limit, the light extraction efficiency can be improved, and the electric resistance can be lowered to reduce the voltage during device light emission. Transparency is enhanced when the thickness of the anode is not more than the above upper limit.

  The surface of the anode is treated with ultraviolet (UV) / ozone, oxygen plasma, or argon plasma for the purpose of removing impurities adhering to the anode and adjusting the ionization potential to improve hole injection. Is preferred.

[Hole injection layer]
The hole injection layer 3 is a layer that transports holes from the anode 2 to the light emitting layer 5, and is usually formed on the anode 2.

  The method for forming the hole injection layer according to the present invention may be either a vacuum deposition method or a wet film formation method, and is not particularly limited, but the hole injection layer is formed by a wet film formation method from the viewpoint of reducing dark spots and short-circuits between both electrodes. It is preferable to form by a method.

  The thickness of the hole injection layer is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less.

{Formation of hole injection layer by wet film formation method}
When the hole injection layer is formed by wet film formation, the material for forming the hole injection layer is usually mixed with an appropriate solvent (hole injection layer solvent) to form a composition for film formation (hole injection). Layer forming composition), and applying this hole injection layer forming composition onto a layer corresponding to the lower layer of the hole injection layer (usually an anode) by an appropriate technique, A hole injection layer is formed by drying.

{Hole transporting compound}
The composition for forming a hole injection layer usually contains a hole transporting compound and a solvent as a constituent material of the hole injection layer.

  The hole transporting compound is a compound having a hole transporting property that is usually used in a hole injection layer of an organic electroluminescence device, and may be a polymer compound or the like, a monomer or the like. Although it may be a low molecular weight compound, it is preferably a high molecular weight compound.

  The hole transporting compound is preferably a compound having an ionization potential of 4.5 eV to 6.0 eV from the viewpoint of a charge injection barrier from the anode to the hole injection layer. Examples of hole transporting compounds include aromatic amine derivatives, phthalocyanine derivatives, porphyrin derivatives, oligothiophene derivatives, polythiophene derivatives, benzylphenyl derivatives, compounds in which tertiary amines are linked by a fluorene group, hydrazone derivatives, silazane derivatives, silanamines Derivatives, phosphamine derivatives, quinacridone derivatives, polyaniline derivatives, polypyrrole derivatives, polyphenylene vinylene derivatives, polythienylene vinylene derivatives, polyquinoline derivatives, polyquinoxaline derivatives, carbon and the like.

  In the present invention, the derivative includes, for example, an aromatic amine derivative, and includes an aromatic amine itself and a compound having an aromatic amine as a main skeleton. It may be a mer.

  The hole transporting compound used as the material for the hole injection layer may contain any one of these compounds alone, or may contain two or more. In the case of containing two or more kinds of hole transporting compounds, the combination is arbitrary, but one or more kinds of aromatic tertiary amine polymer compounds and one or two kinds of other hole transporting compounds. It is preferable to use the above in combination.

  Among the above examples, an aromatic amine compound is preferable from the viewpoint of amorphousness and visible light transmittance, and an aromatic tertiary amine compound is particularly preferable. Here, the aromatic tertiary amine compound is a compound having an aromatic tertiary amine structure, and includes a compound having a group derived from an aromatic tertiary amine.

  The type of the aromatic tertiary amine compound is not particularly limited, but from the viewpoint of uniform light emission due to the surface smoothing effect, a polymer compound having a weight average molecular weight of 1,000 or more and 1,000,000 or less (a polymerizable compound in which repeating units are linked) is further included. preferable. Preferable examples of the aromatic tertiary amine polymer compound include a polymer compound having a repeating unit represented by the following formula (I).

(In the formula (I), Ar ¹ and Ar ² each independently represent an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. .Ar ³ to Ar ^5, the .Z ^b representing each independently, may have a which may have aromatic hydrocarbon group or a substituent substituted aromatic heterocyclic group, the following In addition, two groups bonded to the same N atom among Ar ^{1 to} Ar ⁵ may be bonded to each other to form a ring.

(In the above formulas, Ar ^{6 to} Ar ¹⁶ each independently represents an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. R ¹ and R ² each independently represents a hydrogen atom or an arbitrary substituent.))

As the aromatic hydrocarbon group and aromatic heterocyclic group of Ar ^{1 to} Ar ¹⁶ , a benzene ring, a naphthalene ring, a phenanthrene ring, a thiophene from the viewpoint of the solubility, heat resistance, hole injection / transport property of the polymer compound A group derived from a ring or a pyridine ring is preferred, and a group derived from a benzene ring or a naphthalene ring is more preferred.

The aromatic hydrocarbon group and aromatic heterocyclic group of Ar ^{1 to} Ar ¹⁶ may further have a substituent. The molecular weight of the substituent is usually 400 or less, preferably about 250 or less. As the substituent, an alkyl group, an alkenyl group, an alkoxy group, an aromatic hydrocarbon group, an aromatic heterocyclic group and the like are preferable.

When R ¹ and R ² are optional substituents, examples of the substituent include alkyl groups, alkenyl groups, alkoxy groups, silyl groups, siloxy groups, aromatic hydrocarbon groups, aromatic heterocyclic groups, and the like. .

  Specific examples of the aromatic tertiary amine polymer compound having a repeating unit represented by the formula (I) include those described in International Publication No. 2005/089024.

  In addition, as a hole transporting compound, a conductive polymer (PEDOT / PSS) obtained by polymerizing 3,4-ethylenedioxythiophene (3,4-ethylenedioxythiophene), which is a derivative of polythiophene, in high molecular weight polystyrene sulfonic acid. Is also preferred. Moreover, the end of this polymer may be capped with methacrylate or the like.

  The hole transporting compound may be a crosslinkable polymer described in the section <Hole transporting layer> below. The same applies to the film formation method when the crosslinkable polymer is used.

  The concentration of the hole transporting compound in the composition for forming a hole injection layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.01% by weight or more, preferably in terms of film thickness uniformity. Is 0.1% by weight or more, more preferably 0.5% by weight or more, and usually 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less. When this concentration is not more than the above upper limit, film thickness unevenness is prevented, and when it is not less than the above lower limit, defects in the formed hole injection layer are prevented.

{Electron-accepting compound}
The composition for forming a hole injection layer preferably contains an electron accepting compound as a constituent material of the hole injection layer.

  The electron-accepting compound is preferably a compound having an oxidizing power and the ability to accept one electron from the above-described hole transporting compound, specifically, a compound having an electron affinity of 4 eV or more is preferable, and 5 eV or more. The compound which is the compound of these is further more preferable.

  Examples of such electron-accepting compounds include triarylboron compounds, metal halides, Lewis acids, organic acids, onium salts, salts of arylamines and metal halides, and salts of arylamines and Lewis acids. Examples thereof include one or more compounds selected from the group. More specifically, an onium salt substituted with an organic group such as 4-isopropyl-4′-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate and triphenylsulfonium tetrafluoroborate (International Publication No. WO 2005/089024); High valent inorganic compounds such as iron (III) chloride (Japanese Patent Laid-Open No. 11-251067), ammonium peroxodisulfate; cyano compounds such as tetracyanoethylene, tris (pendafluorophenyl) borane (Japanese Patent Laid-Open No. 2003-31365) Aromatic boron compounds such as); fullerene derivatives; iodine; sulfonate ions such as polystyrene sulfonate ions, alkylbenzene sulfonate ions, camphor sulfonate ions, and the like.

  These electron accepting compounds can improve the conductivity of the hole injection layer by oxidizing the hole transporting compound.

  The content of the electron-accepting compound in the hole-injecting layer or the composition for forming a hole-injecting layer with respect to the hole-transporting compound is usually 0.1 mol% or more, preferably 1 mol% or more. However, it is usually 100 mol% or less, preferably 40 mol% or less.

{Other components}
As a material for the hole injection layer, other components may be further contained in addition to the above-described hole transporting compound and electron accepting compound as long as the effects of the present invention are not significantly impaired. Examples of other components include various light emitting materials, electron transporting compounds, binder resins, and coating property improving agents. In addition, only 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and ratios.

{solvent}
At least one of the solvents of the composition for forming a hole injection layer used in the wet film formation method is preferably a compound that can dissolve the constituent material of the hole injection layer. The boiling point of this solvent is usually 80 ° C. or higher, preferably 100 ° C. or higher, particularly 200 ° C. or higher, usually 400 ° C. or lower, and preferably 300 ° C. or lower. When the boiling point of the solvent is not less than the above lower limit, the drying speed is not too fast, and deterioration of the film quality is prevented. Moreover, when the boiling point of the solvent is not more than the above upper limit, it is not necessary to increase the temperature of the drying step, and there is no possibility of adversely affecting other layers and the substrate.

  Examples of the solvent include ether solvents, ester solvents, aromatic hydrocarbon solvents, amide solvents, and the like.

  Examples of ether solvents include aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA); 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole , Phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, aromatic ethers such as 2,4-dimethylanisole, and the like.

  Examples of the ester solvent include aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate.

  Examples of the aromatic hydrocarbon solvent include toluene, xylene, cyclohexylbenzene, 3-isopropylpropylphenyl, 1,2,3,4-tetramethylbenzene, 1,4-diisopropylbenzene, cyclohexylbenzene, and methylnaphthalene. Can be mentioned.

  Examples of the amide solvent include N, N-dimethylformamide, N, N-dimethylacetamide, and the like.

In addition, dimethyl sulfoxide and the like can also be used.
These solvent may use only 1 type and may use 2 or more types by arbitrary combinations and a ratio.

{Film formation method}
After preparing the composition for forming the hole injection layer, the composition is applied to the layer corresponding to the lower layer of the hole injection layer (usually an anode) by wet film formation, and dried to dry the hole. An injection layer is formed.

  The temperature in the coating step is preferably 10 ° C. or higher and preferably 50 ° C. or lower in order to prevent film loss due to the formation of crystals in the composition.

  Although the relative humidity in an application | coating process is not limited unless the effect of this invention is impaired remarkably, it is 0.01 ppm or more normally, and usually 80% or less.

  After coating, the film of the composition for forming a hole injection layer is usually dried by heating or the like. Examples of the heating means used in the heating step include a clean oven, a hot plate, infrared rays, a halogen heater, microwave irradiation and the like. Among them, a clean oven and a hot plate are preferable in order to uniformly apply heat to the entire film.

  The heating temperature in the heating step is preferably heated at a temperature equal to or higher than the boiling point of the solvent used in the composition for forming a hole injection layer as long as the effects of the present invention are not significantly impaired. In the case of a mixed solvent containing two or more types of solvents used in the hole injection layer, at least one type is preferably heated at a temperature equal to or higher than the boiling point of the solvent. In consideration of an increase in the boiling point of the solvent, the heating step is preferably performed at 120 ° C. or higher, preferably 410 ° C. or lower.

  In the heating step, the heating time is not limited as long as the heating temperature is not lower than the boiling point of the solvent of the composition for forming a hole injection layer and sufficient insolubilization of the coating film does not occur. Is less than a minute. If the heating time is too long, the components of the other layers tend to diffuse, and if it is too short, the hole injection layer tends to be inhomogeneous. Heating may be performed in two steps.

{Formation of hole injection layer by vacuum evaporation}
When forming the hole injection layer by vacuum deposition, one or more of the constituent materials of the hole injection layer (the aforementioned hole transporting compound, electron accepting compound, etc.) are placed in a vacuum vessel. Put in crucibles (in case of using two or more kinds of materials, put them in each crucible), evacuate the inside of the vacuum vessel to about 10 ⁻⁴ Pa with a suitable vacuum pump, and then heat the crucible (two or more kinds) When using materials, heat each crucible) and evaporate by controlling the amount of evaporation (when using two or more materials, evaporate by independently controlling the amount of evaporation) and place it facing the crucible. A hole injection layer is formed on the anode of the substrate. In addition, when using 2 or more types of materials, those hole mixture layers can also be formed by putting them in a crucible and heating and evaporating them.

The degree of vacuum at the time of vapor deposition is not limited as long as the effect of the present invention is not significantly impaired, but is usually 0.1 × 10 ⁻⁶ Torr (0.13 × 10 ⁻⁴ Pa) or more, usually 9.0 × 10 ⁻⁶ Torr. (12.0 × 10 ⁻⁴ Pa) or less. The deposition rate is not limited as long as the effect of the present invention is not significantly impaired, but is usually 0.1 Å / second or more and usually 5.0 Å / second or less. The film forming temperature at the time of vapor deposition is not limited as long as the effect of the present invention is not significantly impaired, but is preferably 10 ° C. or higher, preferably 50 ° C. or lower.

[Hole transport layer]
The hole transport layer 4 is formed on the hole injection layer 3.

  The method for forming the hole transport layer according to the present invention may be a vacuum deposition method or a wet film formation method, and is not particularly limited, but the hole transport layer is formed by wet film formation from the viewpoint of reducing dark spots and short-circuits between both electrodes. It is preferable to form by a method.

  The material for forming the hole transport layer is preferably a material having high hole transportability and capable of efficiently transporting injected holes. Therefore, it is preferable that the ionization potential is small, the transparency to visible light is high, the hole mobility is large, the stability is high, and impurities that become traps are not easily generated during manufacturing or use. In many cases, since it is in contact with the light emitting layer, it is preferable not to quench the light emitted from the light emitting layer or to reduce the efficiency by forming an exciplex with the light emitting layer.

  As a material of such a hole transport layer, any material that has been conventionally used as a constituent material of a hole transport layer may be used. For example, as a hole transport compound used in the above-described hole injection layer What was illustrated is mentioned. In addition, arylamine derivatives, fluorene derivatives, spiro derivatives, carbazole derivatives, pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, phthalocyanine derivatives, porphyrin derivatives, silole derivatives, oligothiophene derivatives, condensed polycyclic aromatics Group derivatives, metal complexes and the like.

In addition, for example, polyvinylcarbazole derivatives, polyarylamine derivatives, polyvinyltriphenylamine derivatives, polyfluorene derivatives, polyarylene derivatives, polyarylene ether sulfone derivatives containing tetraphenylbenzidine, polyarylene vinylene derivatives, polysiloxane derivatives, polythiophenes Derivatives, poly (p-phenylene vinylene) derivatives, and the like. These may be any of an alternating copolymer, a random polymer, a block polymer, or a graft copolymer. Further, it may be a polymer having a branched main chain and three or more terminal portions, or a so-called dendrimer.
Of these, polyarylamine derivatives and polyarylene derivatives are preferred.

The polyarylamine derivative is preferably a polymer containing a repeating unit represented by the following formula (II). In particular, a polymer composed of a repeating unit represented by the following formula (II) is preferable. In this case, Ar ^a or Ar ^b may be different in each repeating unit.

(In formula (II), Ar ^a and Ar ^b each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent.)

  Examples of the aromatic hydrocarbon group which may have a substituent include, for example, a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, and acenaphthene. Examples include a group derived from a 6-membered monocyclic ring or a 2-5 condensed ring, such as a ring, a fluoranthene ring, a fluorene ring, and a group in which these rings are linked by a direct bond.

  Examples of the aromatic heterocyclic group which may have a substituent include a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, and a carbazole ring. , Pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, benzoisoxazole ring, benzoisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine Ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, sinoline ring, quinoxaline ring, phenanthridine ring, benzimidazole ring, perimidine ring, quinazoline ring, quinazolinone ring, azulene ring, etc. ring Are those groups group and the rings of from 2-4 fused ring is linked by a direct bond or two or more rings.

From the viewpoints of solubility and heat resistance, Ar ^a and Ar ^b are each independently selected from the group consisting of a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, triphenylene ring, pyrene ring, thiophene ring, pyridine ring, and fluorene ring. A group derived from a selected ring or a group formed by linking two or more benzene rings (for example, a biphenyl group (biphenyl group) or a terphenylene group (terphenylene group)) is preferable.

  Among these, a group derived from a benzene ring (phenyl group), a group formed by connecting two benzene rings (biphenyl group), and a group derived from a fluorene ring (fluorenyl group) are preferable.

Examples of the substituent that the aromatic hydrocarbon group and aromatic heterocyclic group in Ar ^a and Ar ^b may have include an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, and a dialkyl. Examples thereof include an amino group, a diarylamino group, an acyl group, a halogen atom, a haloalkyl group, an alkylthio group, an arylthio group, a silyl group, a siloxy group, a cyano group, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group.

As a polyarylene derivative, an arylene group such as an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent exemplified as Ar ^a or Ar ^b in the formula (II) is used as ^a repeating unit. The polymer which has is mentioned.

  As the polyarylene derivative, a polymer having a repeating unit composed of the following formula (III-1) and / or the following formula (III-2) is preferable.

(In formula (III-1), R ^a , R ^b , R ^c and R ^d are each independently an alkyl group, an alkoxy group, a phenylalkyl group, a phenylalkoxy group, a phenyl group, a phenoxy group, an alkylphenyl group, Represents an alkoxyphenyl group, an alkylcarbonyl group, an alkoxycarbonyl group, or a carboxy group, and t and s each independently represent an integer of 0 to 3. When t or s is 2 or more, they are contained in one molecule. A plurality of R ^a or R ^b may be the same or different, and adjacent R ^a or R ^b may form a ring.)

(In the formula (III-2), R ^e and R ^f are each independently synonymous with R ^a , R ^b , R ^c or R ^d in the formula (III-1). Independently represents an integer of 0 to 3. When r or u is 2 or more, a plurality of R ^e and R ^f contained in one molecule may be the same or different, and adjacent R ^e or R ^f may form a ring, and X represents an atom or a group of atoms constituting a 5-membered ring or a 6-membered ring.)

Specific examples of X are —O—, —BR—, —NR—, —SiR ₂ —, —PR—, —SR—, —CR ₂ —, or a group formed by bonding thereof. R represents a hydrogen atom or an arbitrary organic group. The organic group in the present invention is a group containing at least one carbon atom.

  In addition to the repeating unit consisting of the formula (III-1) and / or the formula (III-2), the polyarylene derivative further has a repeating unit represented by the following formula (III-3). Is preferred.

(In the formula (III-3), Ar ^{c to} Ar ^j each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent. Independently represents 0 or 1.)

Specific examples of Ar ^{c to} Ar ^j are the same as Ar ^a and Ar ^b in the formula (II).

  Specific examples of the above formulas (III-1) to (III-3) and specific examples of polyarylene derivatives include those described in JP-A-2008-98619.

  When the hole transport layer is formed by a wet film formation method, a composition for forming a hole transport layer is prepared in the same manner as the formation of the hole injection layer, followed by heat drying after the wet film formation.

  The composition for forming a hole transport layer contains a solvent in addition to the above hole transport compound. The solvent used is the same as that used for the composition for forming a hole injection layer. The film forming conditions, heat drying conditions, and the like are the same as in the case of forming the hole injection layer.

  When the hole transport layer is formed by the vacuum deposition method, the film forming conditions are the same as those in the case of forming the hole injection layer.

  The hole transport layer may contain various light emitting materials, electron transport compounds, binder resins, coatability improvers, and the like in addition to the hole transport compound.

  The hole transport layer may also be a layer formed by crosslinking a crosslinkable compound. The crosslinkable compound is a compound having a crosslinkable group, and forms a network polymer compound by crosslinking. The crosslinkable group refers to a group that reacts with the same or different group of other molecules located nearby by irradiation with heat and / or active energy rays to form a new chemical bond.

  Examples of this crosslinkable group include groups derived from cyclic ethers such as oxetane and epoxy; groups derived from unsaturated double bonds such as vinyl, trifluorovinyl, styryl, acrylic, methacryloyl and cinnamoyl; benzo Examples include groups derived from cyclobutene. In terms of easy insolubilization, for example, groups shown in the following [Crosslinkable group T] can be mentioned.

[Crosslinkable group T]

(In formula, R < ¹¹ > -R < ¹⁵ > represents a hydrogen atom or an alkyl group each independently. Ar < ³¹ > may have the aromatic hydrocarbon group or substituent which may have a substituent. Represents an aromatic heterocyclic group.)

  As the crosslinkable group, a cyclic ether group such as an epoxy group or an oxetane group, or a group that is insolubilized by cationic polymerization such as a vinyl ether group is preferable in terms of high reactivity and easy insolubilization. Among these, an oxetane group is particularly preferable in terms of easy control of the rate of cationic polymerization, and a vinyl ether group is preferable in that a hydroxy group that may cause deterioration of the device during cationic polymerization is difficult to generate.

  As the crosslinkable group, an arylvinylcarbonyl group such as a cinnamoyl group and a group that undergoes a cycloaddition reaction such as a group derived from a benzocyclobutene ring are preferable from the viewpoint of further improving electrochemical stability.

  Among the crosslinkable groups, a group derived from a benzocyclobutene ring is particularly preferable in that the structure after insolubilization is particularly stable. Specifically, a group represented by the following formula (IV) is preferable.

(The benzocyclobutene ring in formula (IV) may have a substituent. The substituents may be bonded to each other to form a ring.)

  The crosslinkable compound may be any of a monomer, an oligomer, and a polymer. The crosslinkable compound may have only 1 type, and may have 2 or more types by arbitrary combinations and ratios.

  As the crosslinkable compound, a hole transporting compound having a crosslinkable group is preferably used. Examples of the hole transporting compound include those exemplified above, and those having a crosslinkable group bonded to the main chain or side chain with respect to these hole transporting compounds. In particular, the crosslinkable group is preferably bonded to the main chain via a linking group such as an alkylene group. In particular, the hole transporting compound is preferably a polymer containing a repeating unit having a crosslinkable group, and the above formula (II) and formulas (III-1) to (III-3) can be used as a crosslinkable group. Is preferably a polymer having a repeating unit bonded directly or via a linking group.

  As the crosslinkable compound, a hole transporting compound having a crosslinkable group is preferably used. Examples of hole transporting compounds include nitrogen-containing aromatic compound derivatives such as pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, carbazole derivatives, phthalocyanine derivatives, porphyrin derivatives; triphenylamine derivatives Silole derivatives; oligothiophene derivatives, condensed polycyclic aromatic derivatives, metal complexes and the like. Among them, nitrogen-containing aromatic derivatives such as pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, carbazole derivatives; triphenylamine derivatives, silole derivatives, condensed polycyclic aromatic derivatives, metal complexes, etc. Particularly preferred are triphenylamine derivatives.

  In order to form a hole transport layer by crosslinking a crosslinkable compound, a composition for forming a hole transport layer in which a crosslinkable compound is dissolved or dispersed in a solvent is usually prepared and formed by wet film formation. Crosslink.

  The composition for forming a hole transport layer may contain an additive for promoting a crosslinking reaction in addition to the crosslinking compound. Examples of additives that promote the crosslinking reaction include polymerization initiators and polymerization accelerators such as alkylphenone compounds, acylphosphine oxide compounds, metallocene compounds, oxime ester compounds, azo compounds, onium salts; condensed polycyclic hydrocarbons, And photosensitizers such as porphyrin compounds and diaryl ketone compounds.

  Further, it may contain a coating property improving agent such as a leveling agent and an antifoaming agent; an electron accepting compound; a binder resin;

  In the composition for forming a hole transport layer, the crosslinkable compound is usually 0.01% by weight or more, preferably 0.05% by weight or more, more preferably 0.1% by weight or more, usually 50% by weight or less, preferably 20%. It is contained in an amount of not more than wt%, more preferably not more than 10 wt%.

  After forming a composition for forming a hole transport layer containing a crosslinkable compound at such a concentration on a lower layer (usually a hole injection layer), the crosslinkable compound is formed by heating and / or irradiation with active energy such as light. A network polymer compound is formed by crosslinking.

  Conditions such as temperature and humidity during film formation are the same as those during wet film formation of the hole injection layer.

  The heating method after film formation is not particularly limited. As heating temperature conditions, it is 120 degreeC or more normally, Preferably it is 400 degrees C or less.

  The heating time is usually 1 minute or longer, preferably 24 hours or shorter. The heating means is not particularly limited, and means such as placing a laminated body having a deposited layer on a hot plate or heating in an oven is used. For example, conditions such as heating on a hot plate at 120 ° C. or more for 1 minute or more can be used.

  In the case of irradiation with active energy such as light, a method of irradiating directly using an ultraviolet / visible / infrared light source such as an ultra-high pressure mercury lamp, a high-pressure mercury lamp, a halogen lamp, an infrared lamp, or the above-mentioned light source is incorporated. Examples include a mask aligner and a method of irradiation using a conveyor type light irradiation device. In active energy irradiation other than light, for example, there is a method of irradiation using a so-called microwave oven that irradiates a microwave generated by a magnetron. As the irradiation time, it is preferable to set conditions necessary for reducing the solubility of the film, but irradiation is usually performed for 0.1 seconds or longer, preferably 10 hours or shorter.

  The irradiation of active energy such as heating and light may be performed alone or in combination. When combined, the order of implementation is not particularly limited.

  The film thickness of the hole transport layer thus formed is usually 5 nm or more, preferably 10 nm or more, and usually 300 nm or less, preferably 100 nm or less.

[Hole injection layer / hole transport layer]
In the present invention, the hole injection layer and / or the hole transport layer is formed by a wet film formation method. Preferably, both the hole injection layer and the hole transport layer are formed by a wet film formation method.

In the present invention, preferably, the hole injection layer and / or the hole transport layer, more preferably the hole injection layer and the hole transport layer are formed using a heat-insoluble polyarylamino resin.
Here, as a heat-insoluble polyarylamino resin, the conjugated polymer described in the international publication 2009/102027 pamphlet, the polymer described in the international publication 2010/016555 pamphlet, etc. are mentioned.
By using such a heat-insoluble polyarylamino resin, when forming another organic layer on the hole injection layer or hole transport layer, the lower layer heat-insoluble resin is dissolved in the upper layer coating solvent. The problem can be solved.

  The heat-insoluble polyarylamino resin in the present invention is a polymer having an insolubilizing group. The insolubilizing group is a group that reacts by irradiation with heat and / or active energy rays, and the solubility of the compound (polymer, etc.) to which the group is bonded in an organic solvent or water is higher after the reaction than before the reaction. It is a group having an effect of lowering. Specific examples include a dissociable group or a crosslinkable group.

  Examples of the crosslinkable group and the crosslinkable compound having the group include those described in the section of [Hole Transport Layer]. A crosslinkable group is preferable in that it can cause a large difference in solubility in a solvent of a compound to which the group is bonded before and after the insolubilization reaction.

  The dissociating group refers to a group that dissociates from a bonded aromatic hydrocarbon ring at 70 ° C. or higher and is soluble in a solvent. The dissociation temperature of the group is preferably 100 ° C. or higher, and usually 300 ° C. or lower. Here, being soluble in a solvent means that the compound is dissolved in toluene at 0.1% by weight or more at room temperature in a state before reacting by irradiation with heat and / or active energy rays. The solubility in is preferably 0.5% by weight or more, more preferably 1% by weight or more.

  When a compound having a dissociating group is used as the insolubilizing group, it is preferable in that the charge transport ability of the layer containing the compound after the insolubilizing reaction is excellent. Such a dissociating group is preferably a group that thermally dissociates without forming a polar group on the aromatic hydrocarbon ring side, and more preferably a group that dissociates thermally by a reverse Diels-Alder reaction.

  Specific examples of the dissociating group are shown below, but the dissociating group in the present invention is not limited to these.

  A specific example in the case where the dissociating group is a divalent group is as shown in <Divalent dissociating group group A> below.

<Divalent dissociation group A>

  A specific example in the case where the dissociating group is a monovalent group is as shown in <Monovalent dissociating group B> below.

<Monovalent dissociation group B>

  Such an insolubilizing group may be introduced not only in the hole injection layer and hole transport layer forming material, but also in the light emitting layer, hole blocking layer, electron transport layer, or electron injection layer forming material. it can. A layer obtained by performing wet film formation using a material having an insolubilizing group and insolubilizing this is preferable because another layer can be laminated by wet film formation because it is insoluble in a solvent.

[Light emitting layer]
A light emitting layer 5 is provided on the hole transport layer 4. The light emitting layer 5 is a layer that is excited by recombination of holes injected from the anode 2 and electrons injected from the cathode 9 between electrodes to which an electric field is applied, and becomes a main light emitting source.

{Light emitting layer material}
The light emitting layer contains at least a material having a light emitting property (light emitting material) as a constituent material, and preferably a compound having a hole transporting property (hole transporting compound) or an electron transporting material. Contains a compound having properties (electron transporting compound). A light emitting material may be used as a dopant material, and a hole transporting compound, an electron transporting compound, or the like may be used as a host material. There is no particular limitation on the light-emitting material, and a material that emits light at a desired light emission wavelength and has favorable light emission efficiency may be used. Furthermore, the light emitting layer may contain other components as long as the effects of the present invention are not significantly impaired. In addition, when forming a light emitting layer with a wet film-forming method, it is preferable to use a low molecular weight material in any case.

{Luminescent material}
Any known material can be applied as the light emitting material. For example, a fluorescent material or a phosphorescent material may be used, but a phosphorescent material is preferable from the viewpoint of internal quantum efficiency. Alternatively, blue may be used in combination, such as using a fluorescent material, and green and red using a phosphorescent material.

For the purpose of improving the solubility in a solvent, it is preferable to reduce the symmetry and rigidity of the molecules of the luminescent material, or to introduce a lipophilic substituent such as an alkyl group.
Hereinafter, examples of the fluorescent light emitting material among the light emitting materials will be given, but the fluorescent dye is not limited to the following examples.

  Examples of the fluorescent light-emitting material (blue fluorescent dye) that emits blue light include naphthalene, perylene, pyrene, chrysene, anthracene, coumarin, p-bis (2-phenylethenyl) benzene, and derivatives thereof.

Examples of the fluorescent light emitting material (green fluorescent dye) that gives green light emission include quinacridone derivatives, coumarin derivatives, and aluminum complexes such as Al (C ₉ H ₆ NO) ₃ .

  Examples of the fluorescent light emitting material (yellow fluorescent dye) that gives yellow light include rubrene, perimidone derivatives, and the like.

  Examples of the fluorescent light-emitting material (red fluorescent dye) that emits red light include, for example, DCM (4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran) -based compounds, benzopyran derivatives, rhodamine derivatives, Examples thereof include benzothioxanthene derivatives and azabenzothioxanthene.

  As the phosphorescent material, for example, a long-period type periodic table (hereinafter referred to as a long-period type periodic table when referred to as “periodic table” unless otherwise specified) is selected from the seventh to eleventh groups. And an organometallic complex containing a metal.

  Preferred examples of the metal selected from Groups 7 to 11 of the periodic table include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold.

  As the ligand of the complex, a ligand in which a (hetero) aryl group such as a (hetero) arylpyridine ligand or a (hetero) arylpyrazole ligand and a pyridine, pyrazole, phenanthroline, or the like is connected is preferable. A pyridine ligand and a phenylpyrazole ligand are preferable. Here, (hetero) aryl represents an aryl group or a heteroaryl group.

  Specific examples of the phosphorescent material include tris (2-phenylpyridine) iridium, tris (2-phenylpyridine) ruthenium, tris (2-phenylpyridine) palladium, bis (2-phenylpyridine) platinum, tris (2- Phenylpyridine) osmium, tris (2-phenylpyridine) rhenium, octaethyl platinum porphyrin, octaphenyl platinum porphyrin, octaethyl palladium porphyrin, octaphenyl palladium porphyrin, and the like.

  The molecular weight of the compound used as the light emitting material is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 10,000 or less, preferably 5000 or less, more preferably 4000 or less, still more preferably 3000 or less, and usually 100 or more, Preferably it is 200 or more, More preferably, it is 300 or more, More preferably, it is the range of 400 or more. When the molecular weight of the luminescent material is equal to or higher than the above lower limit, the heat resistance is prevented from being lowered, the gas generation is suppressed, the film quality is prevented from being lowered when the film is formed, and the morphology change of the organic electroluminescent element due to migration or the like. Is prevented. On the other hand, when the molecular weight of the light emitting material is not more than the above upper limit, the organic compound can be easily purified and easily dissolved in a solvent.

  In addition, any 1 type may be used for the luminescent material mentioned above, and 2 or more types may be used together by arbitrary combinations and a ratio.

  The ratio of the light emitting material in the light emitting layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.05% by weight or more and usually 35% by weight or less. When the luminescent material is at least the above lower limit, uneven luminescence is prevented, and when it is at the above upper limit, the luminous efficiency is increased. In addition, when using together 2 or more types of luminescent material, it is made for the total content of these to be contained in the said range.

{Hole transporting compound}
The light emitting layer may contain a hole transporting compound as a constituent material. Here, among the hole transporting compounds, examples of the low molecular weight hole transporting compound include various compounds exemplified as (low molecular weight hole transporting compound) in the above-described hole injection layer, For example, two or more condensed aromatic rings including two or more tertiary amines represented by 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl are substituted with nitrogen atoms. Aromatic amine compounds having a starburst structure (Journal of Luminescence, 1997) such as aromatic diamines (Japanese Patent Laid-Open No. 5-234811), 4,4 ′, 4 ″ -tris (1-naphthylphenylamino) triphenylamine , Vol.72-74, pp.985), an aromatic amine compound comprising a tetramer of triphenylamine (Chemical Communica) ions, 1996, pp. 2175), spiro compounds such as 2,2 ′, 7,7′-tetrakis- (diphenylamino) -9,9′-spirobifluorene (Synthetic Metals, 1997, Vol. 91, pp. 209) and the like.

  In the light emitting layer, only one hole transporting compound may be used, or two or more hole transporting compounds may be used in any combination and ratio.

  The ratio of the hole transporting compound in the light emitting layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.1% by weight or more and usually 65% by weight or less. When the hole transporting compound is at least the above lower limit, it is difficult to be affected by a short circuit, and when it is at most the above upper limit, film thickness unevenness is prevented. In addition, when using together 2 or more types of hole transportable compounds, it is made for the total content of these to be contained in the said range.

{Electron transporting compound}
The light emitting layer may contain an electron transporting compound as a constituent material. Here, among the electron transporting compounds, examples of low molecular weight electron transporting compounds include 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND), 2,5, -Bis (6 '-(2', 2 "-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole (PyPySPyPy), bathophenanthroline (BPhen), 2,9-dimethyl-4,7 -Diphenyl-1,10-phenanthroline (BCP, bathocuproin), 2- (4-biphenylyl) -5- (p-tertiarybutylphenyl) -1,3,4-oxadiazole (tBu-PBD), 4 , 4′-bis (9-carbazole) -biphenyl (CBP), etc. In the light emitting layer, only one type of electron transporting compound may be used, or two or more types may be combined in any combination. And it may be used in combination in a ratio.

  The ratio of the electron transporting compound in the light emitting layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.1% by weight or more and usually 65% by weight or less. When the electron transporting compound is not less than the above lower limit, it is difficult to be affected by a short circuit, and when it is not more than the above upper limit, film thickness unevenness is prevented. In addition, when using together 2 or more types of electron transport compounds, it is made for the total content of these to be contained in the said range.

{Formation of light emitting layer}
When the light emitting layer is formed by the wet film forming method according to the present invention, the above material is dissolved in a suitable solvent to prepare a light emitting layer forming composition, which is then formed into a film.

  As the luminescent layer solvent to be contained in the luminescent layer forming composition for forming the luminescent layer by the wet film forming method according to the present invention, any solvent can be used as long as the luminescent layer can be formed. Suitable examples of the solvent for the light emitting layer are the same as those described for the composition for forming a hole injection layer.

  The ratio of the light-emitting layer solvent to the light-emitting layer-forming composition for forming the light-emitting layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 30% by weight or more, usually 99.9% by weight or less, It is. In addition, when mixing and using 2 or more types of solvents as a solvent for light emitting layers, it is made for the sum total of these solvents to satisfy | fill this range.

  The solid content concentration of the light emitting material, hole transporting compound, electron transporting compound and the like in the composition for forming a light emitting layer is usually 0.01% by weight or more and usually 70% by weight or less. When this concentration is not more than the above upper limit, film thickness unevenness is prevented, and when it is not less than the above lower limit, film defects are prevented.

  After wet-deposition of the composition for forming a light emitting layer, the resulting coating film is dried and the solvent is removed to form a light emitting layer. Specifically, it is the same as the method described in the formation of the hole injection layer. The method of the wet film forming method is not limited as long as the effect of the present invention is not significantly impaired, and any of the methods described above can be used.

  The thickness of the light emitting layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 3 nm or more, preferably 5 nm or more, and usually 200 nm or less, preferably 100 nm or less. When the thickness of the light emitting layer is not less than the above lower limit, film defects are prevented, and when it is not more than the above upper limit, the driving voltage is suppressed.

[Hole blocking layer]
A hole blocking layer 6 may be provided between the light emitting layer 5 and an electron injection layer 8 described later. The hole blocking layer 6 is a layer laminated on the light emitting layer 5 so as to be in contact with the interface on the cathode side 9 of the light emitting layer 5.

  The hole blocking layer 6 has a role of blocking holes moving from the anode 2 from reaching the cathode 9 and a role of efficiently transporting electrons injected from the cathode 9 toward the light emitting layer 5. Have

  The physical properties required for the material constituting the hole blocking layer include high electron mobility, low hole mobility, large energy gap (difference between HOMO and LUMO), and excited triplet level (T1). It is expensive. Examples of the material for the hole blocking layer satisfying such conditions include bis (2-methyl-8-quinolinolato) (phenolato) aluminum, bis (2-methyl-8-quinolinolato) (triphenylsilanolato) aluminum, and the like. Mixed metal complexes such as bis (2-methyl-8-quinolato) aluminum-μ-oxo-bis- (2-methyl-8-quinolinato) aluminum binuclear metal complexes, distyrylbiphenyl derivatives, etc. Triazole derivatives such as styryl compounds (JP-A-11-242996), 3- (4-biphenylyl) -4-phenyl-5 (4-tert-butylphenyl) -1,2,4-triazole (JP-A-7 -41759), phenanthroline derivatives such as bathocuproine (JP-A-10-79297), and the like. That. Furthermore, compounds having at least one pyridine ring substituted at the 2,4,6-positions described in International Publication No. 2005-022962 are also preferable as the material for the hole blocking layer.

  In addition, the material of a hole-blocking layer may use only 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  There is no restriction | limiting in the formation method of a hole-blocking layer. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

  The thickness of the hole blocking layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.3 nm or more, preferably 0.5 nm or more, and usually 100 nm or less, preferably 50 nm or less.

[Electron transport layer]
An electron transport layer 7 may be provided between the light emitting layer 5 and an electron injection layer 8 described later.

  The electron transport layer 7 is provided for the purpose of further improving the light emission efficiency of the device, and efficiently transports electrons injected from the cathode 9 between the electrodes to which an electric field is applied in the direction of the light emitting layer 5. Formed from a compound capable of

  The electron transporting compound used for the electron transporting layer is usually a compound that has high electron injection efficiency from the cathode or the electron injection layer and has high electron mobility and can efficiently transport the injected electrons. Is used. Examples of the compound satisfying such conditions include metal complexes such as aluminum complexes of 8-hydroxyquinoline (Japanese Patent Laid-Open No. 59-194393), metal complexes of 10-hydroxybenzo [h] quinoline, oxadiazole derivatives , Distyrylbiphenyl derivatives, silole derivatives, 3-hydroxyflavone metal complexes, 5-hydroxyflavone metal complexes, benzoxazole metal complexes, benzothiazole metal complexes, trisbenzimidazolylbenzene (US Pat. No. 5,645,948), quinoxaline compounds ( JP-A-6-207169), phenanthroline derivative (JP-A-5-331459), 2-t-butyl-9,10-N, N'-dicyanoanthraquinonediimine, n-type hydrogenated amorphous silicon carbide , N-type zinc sulfide, n-type zinc Such as emissions of zinc, and the like.

  In addition, only 1 type may be used for the material of an electron carrying layer, and 2 or more types may be used together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of an electron carrying layer. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

  The thickness of the electron transport layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 1 nm or more, preferably 5 nm or more, and usually 300 nm or less, preferably 100 nm or less.

[Electron injection layer]
The electron injection layer 8 plays a role of efficiently injecting electrons injected from the cathode 9 into the light emitting layer 5.

  In order to perform electron injection efficiently, the material for forming the electron injection layer is preferably a metal having a low work function. Examples include alkali metals such as sodium and cesium, alkaline earth metals such as barium and calcium, and the film thickness is preferably from 0.1 nm to 5 nm.

  Furthermore, an organic electron transport compound represented by a metal complex such as a nitrogen-containing heterocyclic compound such as bathophenanthroline or an aluminum complex of 8-hydroxyquinoline is doped with an alkali metal such as sodium, potassium, cesium, lithium, or rubidium ( (As described in JP-A-10-270171, JP-A-2002-1000047, JP-A-2002-1000048, etc.), it is possible to improve the electron injection / transport properties and achieve excellent film quality. preferable. In this case, the film thickness is usually 5 nm or more, preferably 10 nm or more, and is usually 200 nm or less, preferably 100 nm or less.

  In addition, only 1 type may be used for the material of an electron injection layer, and 2 or more types may be used together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of an electron injection layer. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

[cathode]
The cathode 9 plays a role of injecting electrons into a layer on the light emitting layer 5 side (such as the electron injection layer 8 or the light emitting layer 5).

  As the material of the cathode, it is possible to use the material used for the anode described above, but in order to perform electron injection efficiently, a metal having a low work function is preferable, for example, tin, magnesium, indium, calcium, A suitable metal such as aluminum or silver or an alloy thereof is used. Specific examples include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, and aluminum-lithium alloy.

  In addition, only 1 type may be used for the material of a cathode, and 2 or more types may be used together by arbitrary combinations and a ratio.

  The thickness of the cathode is usually the same as that of the anode.

  Further, for the purpose of protecting the cathode made of a low work function metal, it is preferable to further stack a metal layer having a high work function and stable to the atmosphere because the stability of the device is increased. For this purpose, for example, metals such as aluminum, silver, copper, nickel, chromium, gold and platinum are used. In addition, these materials may be used only by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

[Other layers]
The organic electroluminescent element according to the present invention may have another configuration without departing from the gist thereof. For example, as long as the performance is not impaired, an arbitrary layer may be provided between the anode 2 and the cathode 9 in addition to the layers described above, and an arbitrary layer may be omitted. .

Examples of the layer that may be included include an electron blocking layer.
The electron blocking layer is provided between the hole injecting layer or the hole transporting layer and the light emitting layer, and prevents electrons moving from the light emitting layer from reaching the hole injecting layer. Increases the recombination probability of holes and electrons, and has the role of confining the generated excitons in the light-emitting layer and the role of efficiently transporting holes injected from the hole injection layer toward the light-emitting layer. . In particular, when a phosphorescent material or a blue light emitting material is used as the light emitting material, it is effective to provide an electron blocking layer.

  The characteristics required for the electron blocking layer include high hole transportability, a large energy gap (difference between HOMO and LUMO), and a high excited triplet level (T1). Furthermore, in the present invention, when the light emitting layer is formed as an organic layer according to the present invention by a wet film formation method, the electron blocking layer is also required to be compatible with the wet film formation. Examples of the material used for such an electron blocking layer include a copolymer of dioctylfluorene and triphenylamine typified by F8-TFB (International Publication No. 2004/084260).

  In addition, the material of an electron blocking layer may use only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of an electron blocking layer. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

Further, at the interface between the cathode and the light emitting layer or the electron transport layer, for example, lithium fluoride (LiF), magnesium fluoride (MgF ₂ ), lithium oxide (Li ₂ O), cesium carbonate (II) (CsCO ₃ ), etc. are formed. It is also an effective method to improve the efficiency of the device by inserting a very thin insulating film (0.1 to 5 nm) (Applied Physics Letters, 1997, Vol. 70, pp. 152; No. 74586; IEEE Transactions on Electron Devices, 1997, Vol. 44, pp. 1245; SID 04 Digest, pp. 154, etc.).

  Moreover, in the organic electroluminescent element of this invention, in order to make the color tone of light emission uniform, you may provide the light-diffusion sheet | seat in close contact with the surface on the opposite side to the light emitting layer of a board | substrate. Or you may install the said light-diffusion sheet | seat apart from an element, specifically, 0.1 to 100 mm away from the board | substrate. As the light diffusion sheet, a scatterer having a different refractive index is dispersed in the optical sheet, the surface of the optical sheet is sandblasted, or an uneven surface is formed by light or heat imprint (mold press), etc. The diffusion angle of the diffusion sheet is preferably 50 ° or more and more preferably 60 ° or more and 100 ° or less from the viewpoint of light extraction efficiency.

  In particular, the interference exposure method (Proceedings of SPIE-The International Society for Optical Engineering (1988), 883 (Hologr.Opt.:Des.Appl.)), 84-93, and Proceedings of SPIE- Using the International Society for Optical Engineering (1990), 1213 (Photopolym. Device Phys., Chem., Appl.), Technology similar to that described in 100-10), surface processing into a large area and roll (cylinder) shape Light diffusion control sheet (relief holographic diffusion sheet) (Lumit's Light Shaping Diffuser: LSD) obtained by using the applied master roll (mold) has high scattering efficiency, and light such as backscattering The light diffusion that lowers the extraction efficiency can be suppressed, which is most preferable.

Moreover, in the organic electroluminescent element of this invention, a light extraction sheet | seat can also be closely_contact | adhered and installed in the surface on the opposite side to the light emitting layer of a board | substrate. Examples of the light extraction sheet include a lens sheet having a lens diameter of 0.5 to 500 μm and a height / lens diameter of 0.2 to 2, and a prism sheet having a prism side of 0.5 to 500 μm and an apex angle of 50 to 150 °. A light diffusion sheet having a diffusion angle of 50 ° or more can be used. The relief holographic diffusion sheet is particularly preferable from the viewpoint of suppressing total reflection at the interface between the light extraction sheet and the atmosphere and efficiently transmitting light to the atmosphere.
The light extraction sheet can also serve as the light diffusion sheet.

  Moreover, in the layer structure demonstrated above, it is also possible to laminate | stack components other than a board | substrate in reverse order. For example, in the case of the layer configuration of FIG. 1, the other components on the substrate are cathode, electron injection layer, electron transport layer, hole blocking layer, light emitting layer, hole transport layer, hole injection layer, anode, and scattering. You may provide in order of a layer.

  Furthermore, it is also possible to constitute the organic electroluminescent element according to the present invention by laminating components other than the substrate between two substrates, at least one of which is transparent.

In addition, a structure in which a plurality of components (light emitting units) other than the substrate are stacked in a plurality of layers (a structure in which a plurality of light emitting units are stacked) may be employed. In that case, instead of the interface layer between the steps (between the light emitting units) (in the case where the anode is ITO and the cathode is Al, these two layers), for example, a charge made of vanadium pentoxide (V ₂ O ₅ ) or the like. When a generation layer (Carrier Generation Layer: CGL) is provided, a barrier between steps is reduced, which is more preferable from the viewpoint of light emission efficiency and driving voltage.

  Furthermore, the organic electroluminescent device according to the present invention may be configured as a single organic electroluminescent device, or may be applied to a configuration in which a plurality of organic electroluminescent devices are arranged in an array. You may apply to the structure by which the cathode is arrange | positioned at XY matrix form.

  Each layer described above may contain components other than those described as materials unless the effects of the present invention are significantly impaired.

In the organic electroluminescent device of the present invention, from the environmental consideration of CO ₂ reduction and energy consumption reduction, the light emitting layer and cathode of the device used for a long time are removed, and a new light emitting layer and cathode are formed and sealed. The organic electroluminescence device can be regenerated by stopping the operation, and the glass substrate can be used repeatedly.

[Organic EL module]
The organic EL module of the present invention includes a plurality of organic electroluminescent elements of the present invention described above, and a stacking direction and a crossing direction (usually, a scattering layer, a hole injection layer, a hole transport layer, a light emitting layer, etc.) on a glass substrate (usually The light emitting layers included in the plurality of organic electroluminescent elements each have a specific spectrum.

[Organic EL display device]
The organic EL display device of the present invention uses the above-described organic electroluminescent element of the present invention. There is no restriction | limiting in particular about the model and structure of the organic electroluminescent display apparatus of this invention, It can assemble in accordance with a conventional method using the organic electroluminescent element of this invention.
For example, the organic EL display device of the present invention can be obtained by the method described in “Organic EL display” (Ohm, published on Aug. 20, 2004, Shizushi Tokito, Chiba Adachi, Hideyuki Murata). Can be formed.

[Organic EL lighting]
The organic EL lighting of the present invention uses the above-described organic electroluminescent element or organic EL module of the present invention. There is no restriction | limiting in particular about the type and structure of the organic EL illumination of this invention, It can assemble in accordance with a conventional method using the organic electroluminescent element or organic EL module of this invention.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples, and the present invention can be arbitrarily modified and implemented without departing from the gist thereof.

[Example 1]
The organic electroluminescent element 20 shown in FIG. 1 was produced by the following method.

<Formation of scattering layer 1>
Using a ball mill ("Universal Ball Mill Model RBD-21" manufactured by Tanaka Rack Co., Ltd.), a high refractive glass (K-VC89) (refractive index n = 1.8) manufactured by Sumita Optical Glass Co., Ltd. having a softening temperature of 550 ° C. By pulverizing, 20 g of glass frit having an average particle diameter of 5 μm (hereinafter, this glass frit may be referred to as “glass frit A”) was produced. The glass frit A, 35 g of α-terpineol solution (E3-260) of 15% by weight ethylcellulose manufactured by Nisshin Kasei Co., Ltd., and 20 g of α-terpineol were stirred at 60 ° C. for 1 hour to obtain a scattering layer coating solution (hereinafter referred to as “the scattering layer coating solution”). This scattering layer coating solution is sometimes referred to as “frit ink 1”).

  After applying this frit ink 1 on a glass substrate (CP600V) (refractive index n = 1.52) manufactured by Central Glass Co., Ltd. having a thickness of 0.7 mm so that the film thickness after drying is 15 μm. And dried on a hot plate at 180 ° C. for 20 minutes. Subsequently, using a muffle furnace (KDF-S-7) manufactured by Kenden Co., Ltd., the temperature was raised at a rate of 19 ° C. per minute until it reached 560 ° C., held at 560 ° C. for 15 minutes, then allowed to cool naturally, and glass A bubble type scattering layer 1 having a film thickness of 10 μm was formed on the substrate.

When the cross section of the formed scattering layer was observed with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd., it was confirmed that bubbles having a particle diameter of 1 to 10 μm and an average particle diameter of 5 μm were distributed as follows. It was.
Region a having a thickness of 2 μm from the glass substrate side: number density 7 to 8 × 10 ⁸ pieces / m ³
A region c having a thickness of 2 μm from the surface layer (anode forming surface side): number density 2 to 4 × 10 ⁸ pieces / m ³
Region b between region a and region c: number density 7-8 × 10 ⁸ / m ³

Further, the transmittance of light at a wavelength of 610 nm was measured for the glass substrate having this scattering layer with an ultraviolet-visible spectrophotometer ("U-3900" manufactured by Hitachi, Ltd.), and it was 50%.
Furthermore, the surface roughness (Ra) of the scattering layer between 10 μm was measured using a step / surface roughness / fine shape measuring device (P-6) manufactured by KLA-Tencor Japan, and the result was 6 nm.

<Formation of anode 2>
An indium tin oxide (ITO) transparent conductive film having a thickness of 150 nm was formed as the anode 2 on the scattering layer 1.

<Formation of hole injection layer 3>
A polymer compound (HI-1) having a repeating unit shown below and 4-isopropyl-4-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate are mixed at a weight ratio of 100: 20, and the concentration of the mixture is 2.0. A composition for forming a hole injection layer dissolved in ethyl benzoate so as to have a weight% was prepared.

  This composition for forming a hole injection layer was spin-coated on the anode 2 in two steps of spinner rotation speed of 500 rpm for 2 seconds and 1500 rpm for 30 seconds in the atmosphere, and then heated at 230 ° C. for 1 hour. As a result, a hole injection layer 3 having a thickness of 30 nm was formed.

<Formation of hole transport layer 4>
A composition for forming a hole transport layer was prepared by dissolving a polymer compound (HT-1) having the following repeating unit in cyclohexylbenzene so as to have a concentration of 1.0% by weight.

  This composition for forming a hole transport layer was spin-coated on the hole injection layer 3 in a dry nitrogen atmosphere in two stages of a spinner rotation speed of 500 rpm for 2 seconds and 1500 rpm for 120 seconds, and then 230 ° C. The hole transport layer 4 having a film thickness of 15 nm was formed by heating for 1 hour.

<Formation of the light emitting layer 5>
Blue fluorescent material BH-1 and BD-1 shown below are mixed at a weight ratio of 100: 7 and dissolved in cyclohexylbenzene so that the mixture concentration becomes 6.0% by weight. A product was prepared.

  By spin-coating the composition for forming a light emitting layer on the hole transport layer 4 in two steps of spinner rotation speed of 500 rpm for 2 seconds and 2250 rpm for 120 seconds, and then heating at 130 ° C. for 1 hour, A light emitting layer 5 having a thickness of 50 nm was formed.

<Formation of hole blocking layer 6 and electron transport layer 7>
A compound HB-1 shown below was deposited on the light emitting layer 5 by a vacuum deposition method so as to have a film thickness of 10 nm, thereby forming a hole blocking layer 6.

  Further, on the hole blocking layer 6, tris (8-hydroxyquinolinate) aluminum was deposited by a vacuum deposition method so as to have a film thickness of 20 nm, thereby forming the electron transport layer.

<Formation of Electron Injection Layer 8 and Cathode 9>
On the electron transport layer 7, lithium fluoride (LiF) is deposited by a vacuum deposition method so as to have a film thickness of 0.5 nm to form the electron injection layer 8, and then the aluminum is vacuum deposited so that the film thickness becomes 80 nm. The cathode 9 was formed by evaporation.

<Sealing>
Subsequently, in a nitrogen glove box, a photocurable resin was applied to the outer periphery of the glass plate for sealing, and a moisture getter sheet was installed in the center.
This sealing glass plate is bonded to the above-mentioned element in which the laminate from the scattering layer to the cathode is laminated on the glass substrate, and then the ultraviolet light is irradiated only to the region where the photocurable resin is applied. Then, the organic electroluminescent element was sealed by curing the resin.

<Measurement of light intensity (μW)>
A voltage of 7 V was applied to the obtained device, and the intensity of the light emitted was measured with a “Digital Photometer” manufactured by Industrial Fiber Optics having a 10 mm square detector at a distance of 2 mm from the surface of the device.

[Example 2]
An organic electroluminescent device was produced and evaluated in the same manner as in Example 1 except that the scattering layer was formed as follows.

<Formation of scattering layer>
The frit ink 1 in Example 1 was applied on an 0.7 mm thick glass substrate (CP600V) (refractive index n = 1.52) manufactured by Central Glass with an applicator so that the film thickness after drying was 15 μm. Then, it was dried at 180 ° C. for 20 minutes on a hot plate. Subsequently, using a muffle furnace (KDF-S-7) manufactured by Kenden Co., Ltd., the temperature was raised at a rate of 19 ° C. per minute until it reached 580 ° C., held at 580 ° C. for 15 minutes, and then allowed to cool naturally. A bubble type first scattering layer having a film thickness of 10 μm was formed on the substrate.

Next, the same operation as in the formation of the first scattering layer was performed except that the frit ink 1 was coated on the first scattering layer with an applicator so that the film thickness after drying was 10 μm. A bubble-type second scattering layer having a thickness of 6 μm was formed.
Hereinafter, the first scattering layer and the second scattering layer are collectively referred to as “laminated scattering layer”.

Observation of a cross section of the laminated scattering layer with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd. confirmed that bubbles having a particle diameter of 1 to 4 μm and an average particle diameter of 2 μm were distributed as follows. .
Region a having a thickness of 3 μm on the glass substrate side: number density of 3 to 5 × 10 ⁸ pieces / m ³
Surface layer (anode forming surface side) thickness 3 μm region c: number density 8 to 10 × 10 ⁸ pieces / m ³
Region b between region a and region c: Number density 5-7 × 10 ⁸ / m ³

Further, the transmittance of light at a wavelength of 610 nm was measured for the glass substrate having the laminated scattering layer with an ultraviolet-visible spectrophotometer ("U-3900" manufactured by Hitachi, Ltd.) and found to be 40%.
Furthermore, the surface roughness (Ra) of the laminated scattering layer between 10 μm was measured using a step / surface roughness / fine shape measuring device (P-6) manufactured by KLA-Tencor Japan, and found to be 3 nm.

[Example 3]
An organic electroluminescent device was produced and evaluated in the same manner as in Example 1 except that the scattering layer was formed as follows.

<Formation of scattering layer>
20 g of glass frit A in Example 1, 0.3 g of hollow glass beads (Spheric HSC-110) (average particle size 6 μm) manufactured by Potters Ballotini Co., Ltd., and 20 g of α-terpineol were stirred at 60 ° C. for 1 hour and scattered. A layer coating solution (hereinafter, this scattering layer coating solution may be referred to as “frit ink 2”) was prepared.

  After applying this frit ink 2 on a glass substrate (CP600V) (refractive index n = 1.52) manufactured by Central Glass Co., Ltd. having a thickness of 0.7 mm so that the film thickness after drying becomes 20 μm, It was dried on a hot plate at 180 ° C. for 20 minutes. Next, using a muffle furnace (KDF-S-7) manufactured by Kenden Co., Ltd., the temperature was increased at a rate of 20 ° C. until the wavelength reached 610 ° C., held at 610 ° C. for 15 minutes, and then allowed to cool naturally. A bubble type scattering layer having a film thickness of 16 μm was formed.

When the cross section of the formed scattering layer was observed with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd., bubbles with a particle diameter of 1 to 10 μm and an average particle diameter of 6 μm were number density 7 to 9 × 10 ^{8 in the} scattering layer. It was uniformly distributed in the scattering layer at the number of particles / m ³ .

Further, the transmittance of light at a wavelength of 610 nm was measured for the glass substrate having the scattering layer with an ultraviolet-visible spectrophotometer (“U-3900” manufactured by Hitachi, Ltd.) and found to be 30%.
Furthermore, the surface roughness (Ra) of the scattering layer between 10 μm was measured using a step / surface roughness / fine shape measuring device (P-6) manufactured by KLA-Tencor Japan, and found to be 4 nm.

[Example 4]
An organic electroluminescent device was produced and evaluated in the same manner as in Example 1 except that the scattering layer was formed as follows.

<Formation of scattering layer>
20 g of glass frit A in Example 1 and 40 g of α-terpineol were stirred at 60 ° C. for 1 hour to prepare a scattering layer coating solution (hereinafter, this scattering layer coating solution may be referred to as “frit ink 3”). did.

  After applying this frit ink 3 on a glass substrate (CP600V) (refractive index n = 1.52) manufactured by Central Glass Co., Ltd. having a thickness of 0.7 mm so that the film thickness after drying becomes 10 μm, It was dried on a hot plate at 180 ° C. for 20 minutes. Subsequently, using a muffle furnace (KDF-S-7) manufactured by Kenden Co., Ltd., the temperature was increased at a rate of 18 ° C. per minute until reaching 550 ° C., held at 550 ° C. for 15 minutes, and then allowed to cool naturally. A glass frit unmelted core type scattering layer having a thickness of 8 μm was formed.

When the cross section of this scattering layer was observed with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd., glass frit unmelted nuclei with a particle size of 1 to 3 μm and an average particle size of 2 μm had a number density of 6 × 10 ⁸ particles / m ^3. And uniformly distributed in the scattering layer.

Further, the light transmittance at a wavelength of 610 nm was measured for the glass substrate having this scattering layer with an ultraviolet-visible spectrophotometer ("U-3900" manufactured by Hitachi, Ltd.), and it was 10%.
Furthermore, when the surface roughness (Ra) of the scattering layer between 10 micrometers was measured using the level | step difference, surface roughness, fine shape measuring apparatus (P-6) by KLA-Tencor Japan, it was 10 nm.

[Example 5]
Instead of forming the scattering layer on the glass substrate, the organic electroluminescence device was prepared and evaluated in the same manner as in Example 1 except that a glass substrate having a light scattering function was prepared and used as follows. went.

<Production of glass substrate having light scattering function>
20 g of glass frit A in Example 1, 1 g of α-terpineol solution (E3-260) of 15% by weight ethyl cellulose manufactured by Nisshin Kasei Co., Ltd. and 30 g of α-terpineol were stirred at 60 ° C. for 1 hour, and a scattering layer coating solution (Hereinafter, this scattering layer coating solution may be referred to as “frit ink 4”).

  The frit ink 4 was applied on a ceramic plate by an applicator so that the film thickness after drying was 12 mm, and then dried on a hot plate at 180 ° C. for 20 minutes. Next, using a muffle furnace, the temperature was raised at a rate of 23 ° C. per minute until 700 ° C., held at 700 ° C. for 30 minutes, allowed to cool naturally, and peeled off from the ceramic plate to contain bubbles of 8 mm thickness. A glass substrate was obtained.

  Next, this glass substrate was optically polished on both sides to obtain a glass substrate having a thickness of 0.7 mm and having a bubble type light scattering function.

When a cross section of this glass substrate was observed with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd., it was confirmed that bubbles having a particle diameter of 1 to 10 μm and an average particle diameter of 4 μm were distributed as follows.
150 μm thick area a from the side in contact with the porcelain plate: number density 7-9 × 10 ⁶ pieces / m ³
A region c having a thickness of 150 μm from the surface layer (anode forming surface side): number density 7 to 9 × 10 ⁶ pieces / m ³
Region b between region a and region c: number density 7-9 × 10 ⁶ / m ³

Further, with respect to this glass substrate, the light transmittance at a wavelength of 610 nm was measured with an ultraviolet-visible spectrophotometer ("U-3900" manufactured by Hitachi, Ltd.), and it was 20%.
Furthermore, when the surface roughness (Ra) between 10 μm of the surface (anode forming surface side) was measured using a step / surface roughness / fine shape measuring device (P-6) manufactured by KLA-Tencor Japan, it was 1 nm. there were.

[Example 6]
An organic electroluminescent device was produced and evaluated in the same manner as in Example 1 except that the scattering layer was formed as follows.

<Formation of scattering layer>
In the preparation of the frit ink 1 in Example 1, instead of the high refractive glass (K-VC89), the high refractive glass (softening temperature 430 ° C.) of “Composition 2” described in Table 1 above (refractive index n = 2.0) was used in the same manner to prepare a scattering layer coating solution (hereinafter, this scattering layer coating solution may be referred to as “frit ink 5”).

  After applying this frit ink 5 on a glass substrate (CP600V) (refractive index n = 1.52) manufactured by Central Glass Co., Ltd. having a thickness of 0.7 mm so that the film thickness after drying becomes 15 μm, It was dried at 180 ° C. for 20 minutes on a hot plate. Next, using a muffle furnace (KDF-S-7) manufactured by Kenden Co., Ltd., the temperature was raised at a rate of 16.5 ° C. per minute until reaching 500 ° C., held at 500 ° C. for 15 minutes, and then allowed to cool naturally. A bubble type first scattering layer having a thickness of 10 μm was formed on a glass substrate.

Next, the same operation as in the formation of the first scattering layer was performed except that the frit ink 5 was applied on the first scattering layer with an applicator so that the film thickness after drying was 10 μm. A bubble-type second scattering layer having a thickness of 6 μm was formed.
Hereinafter, the first scattering layer and the second scattering layer are collectively referred to as “laminated scattering layer”.

Observation of a cross section of the laminated scattering layer with a scanning electron microscope “S4100” manufactured by Hitachi, Ltd. confirmed that bubbles having a particle diameter of 1 to 3 μm and an average particle diameter of 2 μm were distributed as follows. .
Region a having a thickness of 3 μm on the glass substrate side: number density of 3 to 4 × 10 ⁸ pieces / m ³
Surface layer (anode forming surface side) thickness 3 μm c: number density 7 to 10 × 10 ⁸ pieces / m ³
Region b between region a and region c: number density 5-10 × 10 ⁸ / m ³

Further, with respect to the glass substrate having this laminated scattering layer, the light transmittance at a wavelength of 610 nm was measured with an ultraviolet-visible spectrophotometer ("U-3900" manufactured by Hitachi, Ltd.), and it was 48%.
Furthermore, the surface roughness (Ra) of the laminated scattering layer between 10 μm was measured using a step / surface roughness / fine shape measuring device (P-6) manufactured by KLA-Tencor Japan, and it was 5 nm.

[Reference Example 1]
An organic electroluminescent element was produced and evaluated in the same manner as in Example 1 except that the scattering layer was not formed.
In addition, about the used glass substrate, the surface roughness (Ra) between 10 micrometers measured using the level | step difference, surface roughness, and fine shape measuring apparatus (P-6) by KLA-Tencor Japan was 0.5 nm.

Table 2 summarizes the surface roughness (Ra) and light intensity of the ITO anode forming surface of the organic electroluminescent elements obtained in Examples 1 to 6 and Reference Example 1.
Moreover, the ratio with respect to the light intensity in Reference Example 1 was calculated, and this value was also shown in Table 2 as the light extraction efficiency.

  From Table 2, it can be seen that the light extraction efficiency is improved by forming the scattering layer.

[Comparative Example 1]
In Example 1, the hole injection layer was formed to a thickness of 30 nm by vacuum-depositing copper phthalocyanine, which is a hole injection material, and the hole transport layer was formed from N, N′-di, which is a hole transport material. An organic electroluminescent device was similarly formed except that (1-naphthyl) -N, N′-diphenyl- (1,1′-biphenyl) -4,4′-diamine was formed to a thickness of 15 nm by vacuum deposition. However, the obtained organic electroluminescent device could not obtain light emission due to a short circuit.

DESCRIPTION OF SYMBOLS 1 Scattering layer 2 Anode 3 Hole injection layer 4 Hole transport layer 5 Light emitting layer 6 Hole blocking layer 7 Electron transport layer 8 Electron injection layer 9 Cathode 10 Substrate 20 Organic electroluminescence device

Claims (7)

In the method for producing an organic electroluminescent device having a laminate including a scattering layer, a hole injection layer, a hole transport layer, and a light emitting layer, the scattering layer is composed of high refractive index glass and bubbles as a scatterer, And it is a manufacturing method of the organic electroluminescent element which forms the hole injection layer and / or the hole transport layer by a wet film forming method,
The organic electroluminescent element has a glass substrate that supports the laminate, and the scattering layer is formed adjacent to the glass substrate,
Adjacent to the surface of the scattering layer opposite to the glass substrate side, a transparent electrode is further laminated,
The method for producing an organic electroluminescent element (wherein “scatterer” is characterized in that the number density of the scatterers in the thickness direction of the scattering layer increases toward the transparent electrode in the vicinity of the transparent electrode) Is the number of scatterers per unit volume of the scattering layer (pieces / m ³ ) ”. The method for producing an organic electroluminescent element according to claim 1 , wherein the hole injection layer and the hole transport layer are formed using a heat-insoluble polyarylamino resin. Claim 1, wherein the difference between the number density of the scatterer in the central portion in the thickness direction of the scattering layer, and the number density of the scatterer in the interface side of both of said scattering layer is 30% or less Or the manufacturing method of the organic electroluminescent element of 2 (however, "the number density of the scatterers" is "the number of the scatterers per unit volume of the scattering layer (pieces / m ³ )"). An organic electroluminescent device is manufactured by the method for manufacturing an organic electroluminescent device according to any one of claims 1 to 3 , and a plurality of the organic electroluminescent devices are arranged in parallel in the stacking direction and the crossing direction of the stacked body. A method for manufacturing an organic EL module, wherein each of the light-emitting layers included in the plurality of organic electroluminescent elements has a specific emission spectrum. An organic electroluminescent device is manufactured by the method for manufacturing an organic electroluminescent device according to any one of claims 1 to 3 , and an organic EL display device is manufactured using the organic electroluminescent device. Manufacturing method of EL display device. An organic electroluminescent device is manufactured by the method for manufacturing an organic electroluminescent device according to any one of claims 1 to 3 , and an organic EL illumination is manufactured using the organic electroluminescent device. Manufacturing method of lighting. An organic EL module is manufactured by the manufacturing method of the organic EL module of Claim 4 , and organic EL lighting is manufactured using this organic EL module, The manufacturing method of the organic EL lighting characterized by the above-mentioned.

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