JP2006216344A - Flexible clear electrode substrate and organic electroluminescent display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate for an organic EL display device which can sufficiently prolong its life as an organic EL element when used for an organic display device, with well satisfied flexibility, durability and strength. <P>SOLUTION: In the flexible clear electrode substrate, an inorganic compound layer and an organic compound layer are laminated on one face of a clear-film base material, and an electrode layer consisting of an ITO layer is arranged on its outermost surface. The ITO layer is arranged with an intervention of an inorganic compound layer. An inorganic compound layer is arranged also at the other face of the clear-film base material. The ITO layer has a half-value width of a peak corresponding to its [222] plane in an X-ray diffraction method of 0.95° or more and 1.40° or less. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a flexible transparent electrode substrate, and more particularly to a transparent conductive substrate in which an ITO layer is formed on a substrate in which at least an inorganic compound and an organic compound are laminated on a transparent film substrate.
Main uses of the flexible transparent electrode substrate of the present invention include conventional substrates such as display substrates, illumination substrates, solar cell substrates, circuit board substrates, semiconductor applications, electronic paper applications, etc. It is a flexible electronic device that uses a transparent resin base material that can be replaced with a thin, light, non-breaking, and bendable material.
However, the application is not particularly limited to an electronic device as long as the application requires flexibility and transparent conductivity.

Conventionally, transparent conductive laminates in which a transparent conductive layer is provided on the surface of a polymer film as a substrate have been widely used for transparent heat ray reflectors, transparent planar heating elements, transparent electrodes, and the like.
About the transparent conductive layer formed in this transparent conductive laminate, metal thin film type such as gold (Au), silver (Ag), palladium (Pd), indium oxide (In ₂ O ₃ ), tin oxide (SnO) ₂ ), metal oxide thin film types such as ITO (Indium Tin Oxide) and zinc oxide (ZnO) which are a mixture of these, and metal / metal oxide multilayer thin film types such as TiO ₂ / Ag / TiO ₂ Various things are known.
Among these, metal oxide thin films such as ITO have the characteristics that both translucency and conductivity are very good, and the etching characteristics are also excellent, and the patterning as an electrode is easy. It is what.
For this reason, it is suitably used for a transparent electrode of a display that requires a fine pattern.
Such a metal oxide thin film is formed by various film forming methods such as a vacuum deposition method, a sputtering method, an ion plating method, or a CVD method.
A flexible electrode is manufactured by forming a transparent electrode on a flexible substrate.
Various flexible electronic devices that can be bent and thin such as displays, lighting, solar cells, circuit boards, semiconductors, and electronic paper using such flexible substrates have been developed.

In recent years, a transparent conductive layer has been provided on the surface of a polymer film, which is a base material, as a flexible transparent electrode substrate for organic EL (Electroluminescence) display devices, particularly for portable, small, thin, and lightweight organic EL display devices. Transparent conductive laminates have been used.
In addition, EL elements in organic EL display devices are very sensitive to moisture. In particular, since the light emitting layer contains moisture, the deterioration is accelerated, so various structures for preventing water vapor from entering the organic EL layer have been proposed. ing.
For example, Japanese Patent Application Laid-Open No. 2004-14287 (Patent Document 1) discloses an ITO film that has a structure with high crystallinity and a layer with a low crystallinity structure with improved water vapor permeation prevention, and the ITO film. Although there is a description of the organic EL element used, it is here for an organic EL display device having a structure using a prevention film (water vapor permeation prevention film, moisture barrier film) that prevents moisture from entering the EL element body. A substrate is also described.
JP 2004-14287 A

The organic EL element basically has a structure in which an organic EL layer containing an organic compound is sandwiched between a pair of electrodes of an anode electrode and a cathode electrode, and an anode electrode (anode electrode) / organic EL layer / A laminated structure of cathode electrodes (cathode electrodes) is fundamental.
Here, all the layers provided between the pair of electrodes are collectively referred to as an organic EL layer (also referred to as an organic light emitting layer), and a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer. This includes an electron injection layer and the like.
The pixel electrode and the counter electrode correspond to either an anode electrode or a cathode electrode, respectively, and constitute a pair of electrodes.

In addition, as a material which comprises each layer which comprises an organic EL element, itself is well-known and the following can be used.
The cathode electrode may be made of any material as long as it is a material used for a normal organic EL element, and is particularly preferably a conductive material having a low work function so that electrons can be easily injected. Is, for example, magnesium alloy (MgAg), aluminum, silver or the like.
In the organic EL element, at least one insulating layer can be formed partially on the substrate or the anode.
The insulating layer is preferably made of a resin material containing a photo-curing resin such as an ultraviolet curable resin or a thermosetting resin, and is formed in a pattern so that a portion with the insulating layer becomes a non-light-emitting portion when displaying. Can do.
Moreover, an insulating layer can also be formed as a black matrix by mixing carbon black or the like with this resin material.
It is a laminated structure in which a hole transport layer and a light emitting layer or a hole transport layer, a light emitting layer, and an electron transport layer are laminated between an anode electrode and a cathode electrode. Is a hole transport layer that transports holes to the light emitting layer as an optional layer, and a hole injection layer that injects holes into the hole transport layer, as an essential layer, a light emitting layer made of an organic light emitting material that causes electroluminescence An electron transport layer, an electron injection layer, and the like can be provided.
These layers that can be laminated between the anode electrode and the cathode electrode are collectively referred to as an organic EL layer.
The organic light emitting material constituting the light emitting layer is roughly classified into various types such as a dye material, a metal complex material, or a polymer material.
Examples of dye-based materials include cyclopentadiene derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, Examples thereof include pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, oxadiazole dimers, and pyrazoline dimers.
Examples of the metal complex material include aluminum, quinolinol complex, benzoquinolinol beryllium complex, benzoxazole zinc complex, benzothiazole zinc complex, azomethylzinc complex, porphyrin zinc complex, and europium complex. Examples thereof include metal complexes having Be or the like, or a rare earth metal such as Tb, Eu, or Dy, and having a oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structure, or the like as a ligand.
Examples of polymer materials include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, etc., polyfluorene derivatives, polyvinylcarbazole derivatives, etc. A material obtained by polymerizing the material can be given.
The light emitting layer made of the organic light emitting material can be doped for the purpose of improving the light emission efficiency or changing the light emission wavelength. As a doping material for performing this doping, for example, a perylene derivative, a coumarin derivative, a quinacridone derivative, a squalium derivative, a porphyrin derivative, a styryl dye, a tetracene derivative, a pyrazoline derivative, decacyclene, phenoxazone, and the like can be given.
The hole injection layer is provided between the anode electrode and the hole transport layer or between the anode electrode and the light emitting layer.
As a material constituting the hole injection layer, for example, phenylamine, starburst amine, or phthalocyanine, oxide such as vanadium oxide, molybdenum oxide, ruthenium oxide, or aluminum oxide, amorphous carbon, polyaniline, Or a polythiophene derivative etc. can be mentioned.
The electron transport layer is provided between the light emitting layer and the cathode electrode or between the light emitting layer and the electron injection layer.
Examples of the material constituting the electron transport layer include substances that form a generally stable radical anion and have a large ionization potential, such as oxadiazoles or aluminum quinolinol complexes. A 3,4-oxadiazole derivative, a 1,2,4-triazole derivative, etc. can be mentioned.
The electron injection layer is provided between the electron transport layer and the cathode electrode, or between the cathode electrode and the light emitting layer.
Examples of the material constituting the electron injection layer include a Group 1A or Group 2A metal, or an oxide or halide thereof. Specific examples of the Group 1A metal, oxides thereof, and halides include fuca lithium, sodium oxide, and lithium oxide.
Specific examples of Group 2A metals, oxides and halides thereof include strontium, magnesium oxide, magnesium fluoride, strontium fluoride, calcium, calcium fluoride, barium fluoride, and strontium oxide. Can do.

As described above, in recent years, a transparent conductive laminate in which a transparent conductive layer is provided on the surface of a polymer film as a base material has come to be used as a flexible transparent electrode substrate for an organic EL display device. Accordingly, various substrates for organic EL display devices having a structure for preventing water vapor from entering the EL element main body, which causes deterioration of the life of the organic EL element, have been proposed.
However, in such a substrate for an organic EL display device, when used in an organic EL display device, the lifetime as an organic EL element can be sufficiently extended, and the flexibility of the substrate and the durability of the substrate can be achieved. However, it was not satisfactory enough at the same time, and was a problem.
The present invention corresponds to this, and when used in an organic EL display device, the lifetime as an organic EL element can be made sufficiently long, and the flexibility of the substrate, the durability and strength of the substrate are also improved. An object of the present invention is to provide a substrate for an organic EL display device that is sufficiently satisfactory.

The flexible transparent electrode substrate of the present invention is a flexible transparent electrode in which an inorganic compound layer and an organic compound layer are laminated on one surface side of a transparent film substrate, and an electrode layer made of an ITO layer is disposed on the outermost surface. In the electrode substrate, the ITO layer is disposed via an inorganic compound layer, the inorganic film layer is also disposed on the other surface side of the transparent film base material, and The ITO layer is characterized in that the half width of the peak corresponding to the [222] plane in the X-ray diffraction method is 0.95 degrees or more and 1.40 degrees or less.
And it is said flexible transparent electrode substrate, Comprising: It is a flexible transparent electrode substrate for organic EL display devices which form an organic EL layer on the electrode layer which consists of said ITO layer.
Examples of the layer structure of the organic EL element of the organic EL display device include the various layer structures and materials described above.
Also, any one of the above-described flexible transparent electrode substrates, wherein a first inorganic compound layer, an organic compound layer, a second inorganic compound layer, and an ITO layer are sequentially formed on one surface side of the transparent film base material. It is characterized by being arranged.
In the flexible transparent electrode substrate according to any one of the above, an organic compound layer and an inorganic compound layer are sequentially arranged on the other surface side of the transparent film base material. Further, in any one of the above flexible transparent electrode substrates, the inorganic compound on one side and the other side is made of silicon oxide, silicon nitride, silicon carbide, aluminum oxide, aluminum nitride, indium oxide, tin oxide, zinc oxide or the like. It consists of a transparent inorganic compound or a mixed compound thereof.
Also, any one of the above-mentioned flexible transparent electrode substrates, wherein the water vapor transmission rate is 1 × 10 ⁻² g / m ² / day or less.
In any one of the above-mentioned flexible transparent electrode substrates, the ITO layer is one in which cracks do not occur in the film in a heating process in which heating is performed for 3 cycles at 160 ° C. for 1 hour. It is.
In any one of the above flexible transparent electrode substrates, the ITO layer is formed at a film forming pressure of 0.7 Pa or more and 5.0 Pa or less.
In any one of the above flexible transparent electrode substrates, the organic compound layer is made of acrylate.
Here, the peak corresponding to the [222] plane refers to a peak having the highest relative intensity that appears around the peak angle 2θ = 30.5 degrees when the cubic ITO film is measured.
Further, the water vapor transmission rate here is measured under the condition of 37.8 ° C. and 100% Rh using PARMATRAN 3/31 manufactured by Mocon.
The evaluation of the water vapor transmission rate is used as the gas barrier property evaluation.

The organic EL display device of the present invention is characterized in that the flexible transparent electrode substrate according to any one of claims 1 to 9 is used.
Examples of the layer structure of the organic EL element of the organic EL display device include the various layer structures and materials described above.

(Function)
With such a configuration, the flexible transparent electrode substrate of the present invention can sufficiently extend the lifetime as an organic EL element, particularly when used in an organic EL display device, and the flexibility of the substrate. Thus, it is possible to provide a substrate for an organic EL device that is sufficiently satisfactory in durability and strength as a substrate.
That is, it is possible to provide a good flexible substrate for an organic EL display device.
Specifically, the ITO layer is disposed via an inorganic compound layer, the inorganic compound layer is also disposed on the other surface side of the transparent film substrate, and the ITO layer is In the X-ray diffraction method, this is achieved by the half width of the peak corresponding to the [222] plane being 0.95 degrees or more and 1.40 degrees or less.
Specifically, an electrode layer composed of an ITO layer is disposed on the outermost surface of one side of the transparent film substrate via an inorganic compound layer, and an inorganic compound layer is disposed on the other side of the transparent film substrate. Therefore, when used in an organic EL display device, it is assumed that water vapor can enter the organic EL layer from the flexible transparent electrode substrate side.
Since the ITO layer is disposed via the inorganic compound layer, degassing is suppressed, and when the ITO film is formed, the crystallization is likely to proceed, and heat resistance and plasma resistance are generated on the surface. (222) Planar orientation can be obtained stably.
By arranging the inorganic compound layer on the opposite side of the transparent film substrate from the ITO layer, it is possible to suppress the deformation of the substrate due to the stress during film formation, together with the effect of suppressing degassing, Furthermore, by providing the organic compound layer, stress is relaxed and flexibility can be achieved.
By disposing the organic compound layer on the ITO layer side of the transparent film base material, stress can be relieved and flexibility can be provided, and this also changes the surface shape of the ITO layer. It becomes possible.
That is, by laminating an organic compound layer and an inorganic compound layer on the side of the transparent film substrate on which the ITO layer is provided, a gas barrier property and a surface flatness of the ITO layer can be obtained.
In addition, when the layer structure of the organic compound layer and the inorganic compound layer on both sides of the transparent film substrate is symmetric with respect to the transparent film substrate, the deflection caused by the layer structure of the organic compound layer and the inorganic compound layer Can be difficult to occur.
When used in an organic EL display, a flattening layer is formed with an organic compound layer on the ITO forming side to enable flattening of the ITO layer, and a gas barrier layer against water vapor or the like is formed with an inorganic compound layer. Thus, the gas barrier property can be improved.
Whether the gas barrier property is good or bad is greatly related to the life of the organic EL, and if the gas barrier property is bad, the organic EL layer (light emitting layer) is deteriorated.
In addition, evaluation of surface flatness (evaluation of surface roughness) is measured, for example, using a nanopics manufactured by Seiko Instruments Inc. under conditions of a scan range of 4 μm.

When the half-value width of the peak corresponding to the [222] plane of the ITO layer in the X-ray diffraction method (also referred to as XRD method) is 0.95 degrees or less, when used in an organic EL display device, If a crack occurs and the half width is greater than 1.40 degrees, it is not preferable because it has flexibility but a short emission lifetime when used in an organic EL display device.
Here, the reason why the emission lifetime is shortened is that when the half width of the peak corresponding to the [222] plane is 1.40 degrees or more, the hole is easily deteriorated by the hole injection layer formed on the ITO layer.
Further preferable conditions are 0.98 degrees or more and 1.08 degrees or less.
In general, regarding an ITO film, if the crystallinity is high, that is, if the half width in the X-ray diffraction method is small, the flexibility of the film is inferior and a film crack occurs.
The invention of claim 2 is used as a flexible transparent electrode substrate for an organic EL display device in which an organic EL layer is formed on an electrode layer made of an ITO layer, particularly when the ITO layer is low in crystallinity and non-crystalline. In this case, the ITO film is deteriorated in the characteristics due to the hole transport material on the flexible transparent electrode substrate, and this is realized to recognize that the light emission lifetime of the organic EL element is reduced.

  In particular, it can cope with gas barrier properties and stress relaxation properties, and as a simple structure, as a specific form, a first inorganic compound layer, an organic compound layer, and a second layer are sequentially formed on one surface side of the transparent film substrate. The form which has arrange | positioned the inorganic compound layer and ITO layer, and also the form which has arrange | positioned the organic compound layer and the inorganic compound layer in order on the other surface side of a transparent film base material are mentioned.

One important method for setting the half width in the X-ray diffraction method to a range of 0.95 degrees or more and 1.40 degrees or less is the film forming pressure.
Sputter film formation is usually performed at 0.1 Pa to 0.6 Pa in order to stably maintain the plasma state. In particular, by forming a film formation pressure of 0.7 Pa or more, preferably 1 Pa or more and 5 Pa or less. Thus, a film resistant to the load in the organic EL process can be formed, and by heating the film thus obtained, the half width of the peak corresponding to the [222] plane is 0.95 degrees or more. A film of 40 degrees or less can be obtained.
Incidentally, even if an ITO film produced at a normal film forming pressure is heat-treated, it cannot be used because the stress is strong and cracks are generated.

  The inorganic compound on one side and the other side of the transparent film substrate is made of a transparent inorganic compound such as silicon oxide, silicon nitride, silicon carbide, aluminum oxide, aluminum nitride, indium oxide, tin oxide, zinc oxide or a mixed compound thereof. Things.

A water vapor transmission rate of 1 × 10 ⁻² g / m ² / day or less and good gas barrier property is preferable, but in particular when used for an organic EL display device, 1 × 10 ⁻³ g / m ² / day. It is preferable that it is not more than day, more preferably not more than 1 × 10 ⁻⁴ g / m ² / day.
In addition, when used for an organic EL display device, the ITO layer can be said to be sufficiently reliable if it does not cause cracks in the heating process in which heating is performed for 3 cycles at 160 ° C. for 1 hour.
Moreover, when using for an organic EL display device, an acrylate is mentioned as an organic compound layer.

  By adopting such a configuration, the organic EL display device of the present invention can provide an organic EL display device capable of sufficiently extending the lifetime of the organic EL element.

As described above, the present invention, particularly when used in an organic EL display device, can sufficiently extend the lifetime as an organic EL element, and can provide flexibility and durability as a substrate. It is possible to provide a substrate for an organic EL display device that is sufficiently satisfactory.
At the same time, it was possible to provide an organic EL display device having a sufficiently long life of the organic EL element by using the substrate for an organic EL display device as described above.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a cross-sectional view of an embodiment of a flexible transparent electrode substrate according to the present invention, and FIG. 1B is a display comprising an organic EL element using the flexible transparent electrode substrate shown in FIG. FIG. 2 is a sectional view schematically showing a modification of the embodiment of the flexible transparent electrode substrate of the present invention shown in FIG. 1 (a).
1 and 2, 100 is a flexible transparent electrode substrate, 110 is a transparent film substrate, 120 is a first inorganic compound layer, 125 is a second inorganic compound layer, 127 is an inorganic compound layer, and 130 is an organic compound layer 140 is an ITO layer (also referred to as an electrode layer or an anode electrode layer), 150 is an organic EL layer (also referred to as an organic EL light emitting layer), 160 is a cathode electrode layer, 200 is a flexible transparent electrode substrate, 210 is a transparent film substrate, 220 is a first inorganic compound layer, 225 is a second inorganic compound layer, 227 is an inorganic compound layer, 230 and 235 are organic compound layers, and 240 is an ITO layer (also referred to as an electrode layer or an anode electrode).

First, the 1st example of embodiment of the flexible transparent electrode substrate of this invention is demonstrated based on FIG.
The flexible transparent electrode substrate 100 of the first example includes a first inorganic compound layer 120 as a gas barrier layer, an organic compound layer 130 as a planarizing layer, and a gas barrier layer as one of the surfaces of the transparent film substrate 110. Two inorganic compound layers 125 are laminated in this order, and an electrode layer made of the ITO layer 140 is disposed on the outermost surface, and the gas barrier layer is directly formed on the other surface side of the transparent film substrate 110. It is the flexible transparent electrode substrate for organic EL display devices which has arrange | positioned the inorganic compound layer 127 as.
And as shown in FIG.1 (b), on the anode electrode layer which consists of ITO layer 140 of the flexible transparent electrode substrate 100 of this example, the organic EL layer 150 and the cathode electrode layer 160 are formed in order, and organic EL element And
In this example, in particular, the ITO layer 140 has a peak half-value width corresponding to the [222] plane in the X-ray diffraction method of 0.95 degrees or more and 1.40 degrees or less.
By adopting such a configuration, as a result, it is possible to produce an organic EL element having an unprecedented long life.

The material and function of each part of the flexible transparent electrode substrate 100 of this example will be briefly described below.
The transparent film substrate 110 is not particularly limited as long as it is a transparent polymer film having flexibility. For example, a film having heat resistance at 100 ° C. or higher is preferably exemplified.
Although there is no restriction | limiting in particular also about the thickness of a polymer film, From a viewpoint of flexibility and a form retainability, it is preferable to set it as the range of 50-400 micrometers, for example.
The first inorganic compound layer 120, the second inorganic compound layer 125, and the inorganic compound layer 127 include transparent inorganic materials such as silicon oxide, silicon nitride, silicon carbide, aluminum oxide, aluminum nitride, indium oxide, tin oxide, and zinc oxide. The thing which consists of a compound or its mixed compound is mentioned.
In addition, these can be produced by using various film forming methods such as a vacuum deposition method, a sputtering method, an ion plating method, or a CVD method.
These function as a gas barrier layer that blocks the entry of oxygen and water vapor onto the polymer substrate, and suppresses deformation of the transparent film substrate 110 due to stress. In particular, the second inorganic compound layer 125 is in contact with the ITO layer. It is assumed that degassing is suppressed and crystallization is likely to proceed, and that when the ITO layer 140 is formed, heat resistance and plasma resistance are generated on the surface thereof, and (222) plane orientation can be stably performed.
In the case of this example, since it is used for an organic EL display device, the water vapor permeability is 10 ⁻³ g / m ² / day or less.
If the gas barrier property is poor, the light emitting layer is deteriorated.
Here, the gas barrier property refers to that measured using a PARMATRAN 3/31 manufactured by Mocon under the conditions of 37.8 ° C. and 100% Rh.
As the organic compound layer 130, acrylate is used as a general-purpose material, but styrene, phenol, epoxy, nitrile, acrylic, amine, ethyleneimine, ester, silicone, alkyl titanate compound, ionic polymer complex, etc. A photo-curing or thermosetting material is appropriately used.
The organic compound layer 130 has a function as a stress relaxation layer in addition to a function as a planarization layer.
The ITO layer 140 is preferably an ITO single layer in which indium oxide (In ₂ O ₃ ) or tin oxide (SnO ₂ ) is mixed with 3 to 15 wt%.
The thickness is preferably, for example, 1000 to 10,000 mm, and within this range, the surface resistance can be 100 Ω / cm ² , or even 10 Ω / cm ² or less.
If it deviates from this range, the translucency is lowered or the properties such as conductivity become insufficient.
The transparent conductive layer may be formed once or may be laminated in multiple steps.
Further, by using a single layer, the etching property is improved as compared with the multilayer structure.
And delamination does not occur.
In this example, as described above, the half width of the peak corresponding to the [222] plane of the ITO layer is 0.95 degrees or more and 1.40 degrees or less.
If it is 0.95 degrees or less, cracks occur when an EL element is formed.
Moreover, although it has flexibility at 1.40 degree | times or more, it is unpreferable since it becomes the cause of the light emission lifetime short.
Preferably, the half width is 0.98 degrees or more and 1.08 degrees or less.
Here, the peak corresponding to the [222] plane refers to a peak having the highest relative intensity that appears around a peak angle 2θ = 30.5 degrees when a cubic ITO film is measured.
For example, the measurement is performed under the following measurement conditions using a Rigaku X-ray diffraction apparatus (also referred to as an XRD apparatus).
・ X-ray: 50 kV, 300 mA
Scan speed: 4.0000 ° / min
・ Sampling width: 0.0400 °
Operation range: 5.0000 ° to 120.000 °
Incident monochrome: slit collimation Counter monochromator: light receiving slit In this example, the ITO layer 140 is formed at a deposition pressure of 0.7 Pa or more and 5.0 Pa or less.
As described above, in particular, by setting the film forming pressure to 0.7 Pa or more, it is possible to form a film resistant to the load in the organic EL process, preferably at 1 Pa or more and 5 Pa or less. By heat-treating the obtained film, a film having a peak half-value width corresponding to the [222] plane of 0.95 or more and 1.40 or less can be obtained.
By the way, even if an ITO film produced at a normal film forming pressure (0.1 Pa to 0.6 Pa) is heat-treated, it cannot be used because the stress is strong and cracks are generated.

  In this example, in consideration of the manufacturing process of the organic EL, the ITO layer 140 is a layer in which cracks are not generated in the heating process in which heating is performed for three cycles at 160 ° C. for 1 hour.

  By arranging the first inorganic compound layer 120, the organic compound layer 130 as the planarization layer, and the second inorganic compound layer 125 in this order, the flexible transparent electrode substrate for the organic display device of this example, It is assumed that high gas barrier properties and surface flatness are obtained, which also greatly contributes to extending the life of the organic EL.

Next, a modification of the flexible transparent electrode substrate of this example will be given and described with reference to FIG. The modification shown in FIG. 2 has a structure in which an organic compound layer is provided between the transparent film substrate 110 and the inorganic compound layer 127 in the flexible transparent electrode substrate 100 shown in FIG.
An organic compound layer 235 and an inorganic compound layer 227 are laminated and disposed in this order on the surface of the transparent film substrate 210 that is not on the ITO layer 240 forming side.
In the case of the flexible transparent electrode substrate of this modification, the material and function of each part are basically the same as those of the flexible transparent electrode substrate shown in FIG. 1, and description thereof will be omitted.
The flexible transparent electrode substrate of the modification shown in FIG. 2 also has basically the same function and effect as that shown in FIG. 1, but the layer structure of the inorganic compound layer and the organic compound layer on both sides of the film substrate In terms of the resulting deflection, compared to the flexible transparent electrode substrate shown in FIG. 1 (a), the flexible transparent electrode substrate of the modified example shown in FIG. Yes.
However, the modification shown in FIG. 2 is more difficult and difficult to manufacture in comparison with the flexible transparent electrode substrate shown in FIG.
Each of the forms shown in FIGS. 1 and 2 is an example, and the flexible transparent electrode substrate of the present invention is not limited thereto.
Of course, the layer structure of the organic compound layer and the inorganic compound layer formed on both sides of the transparent film substrate is not limited to these.

As an organic EL display device using the flexible transparent electrode substrate of this example, for example, a bottom emission type organic EL display unit having a cross-sectional structure of an organic EL element as shown in FIG.
The organic EL element emits light by applying an electric field between the electrodes (the anode electrode 140 and the cathode electrode 160) and passing an electric current through the organic EL layer (light emitting layer) 150.
Here, a bottom emission structure that emits light toward the transparent film substrate 110 is used, but there is also a top emission structure that emits light in a direction opposite to that of the transparent film substrate 110.

Next, examples of the present invention and comparative examples will be given to further explain the present invention.
In each of Examples 1 to 3 and Comparative Examples 1 to 3, a flexible transparent electrode substrate having the same layer configuration as that of the flexible transparent electrode substrate shown in FIG. An organic EL element having a cross-sectional structure shown in 1 (b) was produced, and a flexible transparent electrode substrate was evaluated.
This will be described with reference to FIG.
Example 1
A plastic film substrate made of PEN resin having a thickness of 100 μm dried at 160 ° C. for 1 hour by a dryer is used as a transparent film substrate 110, and a silicon oxynitride film having a thickness of 100 nm is formed on both surfaces by sputtering. Formed by.
Thereby, the inorganic compound layers 120 and 127 were formed.
Thereafter, the acrylate resin composition was applied to one surface by spin coating, and dried at 160 ° C. for 1 hour to obtain an organic compound layer 130 made of 1 μm acrylate resin.
Thereafter, an inorganic compound layer 125 made of a silicon oxynitride film having a thickness of 100 nm was further formed on the organic compound layer 130 by a sputtering method to obtain a gas barrier film.
When the gas barrier property was measured, the value was below the measurement limit (1 × 10 ⁻² g / m ² / day or less).
Here, the gas barrier property was measured under the conditions of 37.8 ° C. and 100% Rh using PARMATRAN 3/31 manufactured by Mocon.
An ITO film having a film thickness of 150 nm was formed on one side of the gas barrier film by a sputtering method (Ar: 80 sccm, sputtering power: 1.5 kw, film forming pressure: 0.7 Pa) to obtain a flexible transparent electrode substrate 100.
Thereafter, when the ITO film surface was measured with an XRD apparatus, the half width of the peak corresponding to the [222] plane was 1.05 degrees.
Here, a Rigaku X-ray diffractometer was used as an X-ray diffractometer (also referred to as an XRD apparatus), and measurement was performed under the following measurement conditions.
・ X-ray: 50 kV, 300 mA
Scan speed: 4.0000 ° / min
・ Sampling width: 0.0400 °
Operation range: 5.0000 ° to 120.000 °
・ Incident monochrome: slit collimation ・ Counter monochromator: receiving slit Next, after cleaning the gas barrier film with ITO thin film produced, the ITO film is etched into a predetermined pattern to form an anode electrode and flexible transparent An electrode substrate 100 was obtained.

Next, using the flexible transparent electrode substrate 100 thus manufactured, a display unit made of an organic EL element having a cross-sectional structure shown in FIG.
After cleaning the anode surface of the obtained anode substrate, the following PEDOT / PSS dispersion was applied onto the anode surface by spin coating, and after application, placed on a hot plate at a temperature of 200 ° C. for 30 minutes. Heat to dry.
Further, it was transferred into a glove box substituted with pure nitrogen and again placed on a hot plate at a temperature of 200 ° C. and heated for 15 minutes to dry, and an 80 nm thin film of PEDOT / PSS was obtained on the anode.
PEDOT / PSS = 1/20 (manufactured by Bayer, using Vitron P VP CH8000)
Next, a solution for forming a light emitting layer in which a phosphor for organic EL element (manufactured by Sigma Aldrich, product number: ADS228GE) is mixed in toluene so as to be 1.0% (mass ratio) is prepared. The resulting PEDOT / PSS thin film was applied by spin coating in a glove box, and after application, it was placed on a hot plate at a temperature of 130 ° C. and dried by heating for 1 hour. A layer was formed.
Next, vapor deposition is performed in a glove box on the light emitting layer on the substrate on which the layers up to the light emitting layer are formed, and a 3 nm thick LiF thin film and a 10 nm thick Ca thin film are sequentially formed to inject electrons. Further, an Al thin film having a thickness of 180 nm was formed on the electron injection layer to form a cathode electrode.
Then, what applied the ultraviolet curable adhesive (Nagase Chemtech Co., Ltd. product number; XNR5516HP-B1) to the convex part of the glass for sealing which has a convex part around was formed to said cathode electrode. Laminate on the substrate, irradiate the area where the adhesive was applied with ultraviolet rays to cure the adhesive, and place the superposed substrate after irradiation on a hot plate at a temperature of 80 ° C. for 1 hour. The adhesive was sufficiently cured to form an organic EL element.

By applying a DC voltage between the anode electrode (ITO electrode) and the cathode electrode (also referred to as a back electrode layer) of the display unit made of the organic EL element obtained as described above, both electrodes cross each other. As a result of emitting light from the light emitting layer at a desired position, good light emission was obtained at any position.
And about the display part which consists of an organic EL element obtained in this way, when it measured as an effective lifetime, the effective lifetime was 10000 hr.
Here, with respect to the organic EL element formed as described above, a voltage is continuously applied so that the initial luminance becomes 100 Cd, and a change in luminance with the passage of time is measured. Is defined as the emission lifetime of the organic EL.

(Example 2)
In the same manner as in Example 1, a plastic film substrate made of PEN resin having a thickness of 100 μm, which was dried at 160 ° C. for 1 hour with a dryer, was applied to both surfaces of the transparent film substrate 110, respectively, with the inorganic compound layer 120, An organic compound layer 130 made of 127 acrylate is formed, and an ITO film having a film thickness of 150 nm is sputtered on one side of the gas barrier film (Ar: 360 sccm, oxygen: 3.0 sccm, sputtering power: 1.5 kw, film formation pressure) : 2 Pa) to obtain a flexible transparent electrode substrate 100.
When the crystallinity of the ITO film was measured with an XRD apparatus, the half width of the peak corresponding to the [222] plane was 1.40 degrees.
Except this, it was based on Example 1.
And when the display part which consists of an organic EL element according to Example 1 was produced and the time until the light emission luminance became half of the initial value was measured as the effective lifetime, the effective lifetime was 5000 hr.

(Example 3)
Example 3 is a sample obtained by heat-treating at 160 ° C. for 1 hour after ITO film formation in Example 2, and measuring the crystallinity of the ITO film with an XRD apparatus after the degree of crystallinity. The half width of the corresponding peak was 0.95 degree.
Other than that, it was based on Example 2.
And when the display part which consists of an organic EL element according to Example 1 was produced and the time until the light emission luminance became half of the initial value was measured as the effective lifetime, the effective lifetime was 30000 hr.

(Comparative Example 1)
In the same manner as in Example 1, a plastic film substrate made of PEN resin having a thickness of 100 μm, which was dried at 160 ° C. for 1 hour with a dryer, An organic compound layer 130 made of 127 acrylate is formed, and an ITO film with a film thickness of 150 nm is sputtered on one side of the gas barrier film (Ar: 80 sccm, oxygen: 3.0 sccm, sputtering power: 1.5 kw, film formation pressure) : 0.4 Pa) to obtain a flexible transparent electrode substrate 100.
After ITO film formation, heat treatment was performed at 160 ° C. for 1 hour, and after crystallinity, the crystallinity of the ITO film was measured with an XRD apparatus. The half-value width of the peak corresponding to the [222] plane was 0. It was 94 degrees.
Except this, it was based on Example 1.
And the display part which consists of an organic EL element according to Example 1 was produced, and when the time until the light emission luminance became half of the initial value was measured as the effective life, the effective life was 3000 hr. The film of the layer 140 was cracked and became defective.

(Comparative Example 2)
In the same manner as in Example 1, a plastic film substrate made of PEN resin having a thickness of 100 μm, which was dried at 160 ° C. for 1 hour with a dryer, An organic compound layer 130 made of 127 acrylate is formed, and an ITO film with a film thickness of 150 nm is sputtered on one side of the gas barrier film (Ar: 600 sccm, oxygen: 6.0 sccm, sputtering power: 1.5 kw, deposition pressure) When the crystallinity of the ITO film was measured with an XRD apparatus, the half width of the peak corresponding to the [222] plane was 1.50 degrees.
Most of them were amorphous.
Except this, it was based on Example 1.
Then, a display unit made of an organic EL element was produced in accordance with Example 1, and the time until the light emission luminance became half of the initial value was measured as the effective lifetime. The effective lifetime was as short as 1500 hr and was not suitable for use. It was a thing.

(Comparative Example 3)
In the same manner as in Example 1, a plastic film substrate made of PEN resin having a thickness of 100 μm, which was dried at 160 ° C. for 1 hour with a dryer, The organic compound layer 130 made of 127 acrylate is formed, and the ITO layer 140 is further formed. After the ITO layer 140 is formed, it is heated at 200 ° C. for 3 hours. Was measured with an XRD apparatus, and the half-value width of the peak corresponding to the [222] plane was 0.94 degrees.
And when the display part which consists of an organic EL element was produced based on Example 1, and the time until light emission luminance became half of an initial value was measured as an effective lifetime, the effective lifetime was 30000 hr.
However, the glass substrate was cracked when trying to roll it.

After all, the occurrence of cracks in the flexible transparent electrode substrate (corresponding to 100 in FIG. 1A), the life and effective life of the display unit (see FIG. 1B) made of an organic EL element using the flexible transparent electrode substrate In Examples 1 to 3, there is no problem in terms of the evaluation of strength when the display part is rounded after measuring the presence or absence of the ITO layer and the useful life measurement, and they are sufficiently practical.
In contrast, in Comparative Example 1, the ITO layer was damaged during the useful life, Comparative Example 2 was as short as 1500 hours in useful life, and Comparative Example 3 was used when the display portion was intended to be rounded after measuring the useful life. There was a problem with strength.

FIG. 1A is a cross-sectional view of an embodiment of a flexible transparent electrode substrate according to the present invention, and FIG. 1B is a display comprising an organic EL element using the flexible transparent electrode substrate shown in FIG. Is a cross-sectional view schematically showing the cross-sectional structure of the part It is 1 sectional drawing of the modification of the embodiment of the flexible transparent electrode substrate of this invention shown to Fig.1 (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Flexible transparent electrode substrate 110 Transparent film base material 120 1st inorganic compound layer 125 2nd inorganic compound layer 127 Inorganic compound layer 130 Organic compound layer 140 ITO layer (it is also called an electrode layer or an anode electrode layer)
150 Organic EL layer (also referred to as organic EL light-emitting layer)
160 Cathode electrode layer 200 Flexible transparent electrode substrate 210 Transparent film base material 220 First inorganic compound layer 225 Second inorganic compound layer 227 Inorganic compound layer 230, 235 Organic compound layer 240 ITO layer (also referred to as electrode layer or anode electrode)

Claims (10)

  A flexible transparent electrode substrate in which an inorganic compound layer and an organic compound layer are laminated on one surface side of a transparent film substrate, and an electrode layer made of an ITO layer is disposed on the outermost surface thereof, wherein the ITO layer Is disposed via an inorganic compound layer, the inorganic compound layer is also disposed on the other surface side of the transparent film substrate, and the ITO layer is an X-ray diffraction method. A flexible transparent electrode substrate, wherein a half width of a peak corresponding to the [222] plane is 0.95 degrees or more and 1.40 degrees or less.   2. The flexible transparent electrode substrate according to claim 1, wherein the flexible transparent electrode substrate is an organic EL display device for forming an organic EL layer on the electrode layer made of the ITO layer. substrate.   It is a flexible transparent electrode substrate of any one of Claim 1 thru | or 2, Comprising: On the one surface side of the said transparent film base material, a 1st inorganic compound layer, an organic compound layer, and a 2nd inorganic in order. A flexible transparent electrode substrate comprising a compound layer and an ITO layer.   It is a flexible transparent electrode substrate of any one of Claim 1 thru | or 3, Comprising: On the other surface side of a transparent film base material, the organic compound layer and the inorganic compound layer are distribute | arranged in order, Flexible transparent electrode substrate.   5. The flexible transparent electrode substrate according to claim 1, wherein the inorganic compound on one side and the other side includes silicon oxide, silicon nitride, silicon carbide, aluminum oxide, aluminum nitride, indium oxide, A flexible transparent electrode substrate comprising a transparent inorganic compound such as tin oxide or zinc oxide or a mixed compound thereof. 6. The flexible transparent electrode substrate according to claim 1, wherein the water vapor permeability is 1 × 10 ⁻² g / m ² / day or less.   The flexible transparent electrode substrate according to any one of claims 1 to 6, wherein the ITO layer does not generate cracks in a heating process in which heating is performed for three cycles at 160 ° C for 1 hour. There is a flexible transparent electrode substrate.   8. The flexible transparent electrode substrate according to claim 1, wherein the ITO layer is formed at a film forming pressure of 0.7 Pa or more and 5.0 Pa or less. A flexible transparent electrode substrate.   The flexible transparent electrode substrate according to any one of claims 1 to 8, wherein the organic compound layer is made of acrylate. An organic EL display device using the flexible transparent electrode substrate according to claim 1.

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