JP2022121150A - Light extraction substrate, organic el panel containing them, and manufacturing method of them - Google Patents

Abstract

To provide a high performance organic EL panel.SOLUTION: An organic EL panel 10 of the present invention, is the organic EL panel 10 containing an organic EL element 1 and a sealing film 9 in order on an element formation surface of a light extraction substrate 20 containing a glass substrate 21, a light extraction film 23, and a flatness film 24. The element formation surface is formed by: an element formation region 20A containing a light emission area 1A corresponded to the organic EL element 1 in a flat view; and a frame edge region 20G surrounding them that includes an absence continuous peripheral 20GL without having the sealing film 9. The organic EL element 1 contains: a light transmissivity conductive layer 6; an organic functional layer 7; and a reactive conductive layer 8. The flatness film 24 contains an organic binder, and its whole circumference is surrounded by the light extraction film 23 and the sealing film 9 without being exposed to an external part.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a light extraction substrate, an organic EL panel including the same, and a manufacturing method thereof.

An organic EL element is a surface emitting element that utilizes a phenomenon in which light is emitted when an electric field is applied to a substance. Organic EL panels, in which organic EL elements are formed on a substrate, are being developed for application to flat light sources, displays, etc., taking advantage of their characteristics such as being self-luminous and capable of being made thin.

Here, the organic functional materials used in the light-emitting layer of the organic EL element are easily degraded by moisture and oxygen, causing the generation of dark spots and a decrease in luminous efficiency. It is necessary to have high barrier properties against oxygen and moisture.

Further, the light extraction substrate has a role of efficiently extracting the light from the light emitting portion to the outside. If there is unevenness on the surface of the light extraction substrate that is in contact with the organic EL element, especially its organic functional layer, the power luminous efficiency of the organic EL panel will decrease and the leakage current will increase. requested.

Patent Document 1 relates to such a light extraction substrate. In a chemically strengthened thin glass substrate provided with an alkali barrier film, the light extraction efficiency is reduced due to the light absorption and light scattering properties of the alkali barrier film itself, and the alkali In response to the concern that the lack of flatness of the surface of the barrier film causes the leakage current of the organic EL element to increase and the reliability to decrease, the alkali barrier film is replaced with , An organic EL panel comprising an organic EL element via a specific light extraction structure on a chemically strengthened thin glass substrate having a main surface including a specific barrier film and a specific smooth region, Disclosed is to obtain a high-performance organic EL panel without impairing organic EL characteristics.

Patent Document 2 describes a light extraction substrate, which is a light-transmitting substrate capable of forming a light-transmitting electrode layer with excellent surface smoothness and having a scattering layer with greater scattering properties, as a light-transmitting substrate with a glass base material. , and a light-transmitting substrate with a scattering layer for forming a light-transmitting electrode layer, wherein the surface of the scattering layer opposite to the glass substrate side is the surface for forming the light-transmitting electrode layer. wherein the scattering layer comprises an amorphous matrix of a first glass material, crystallite particles dispersed in the amorphous matrix and comprising crystallites of the first glass material, and Disclosed is a light-transmitting substrate with a scattering layer for forming a light-transmitting electrode layer, comprising glass particles of a second glass material having a melting point higher than that of the first glass material dispersed in a crystalline matrix. do.

International publication WO2019/004061 pamphlet JP 2019-175693 A

By using such a light extraction substrate, the performance of the organic EL panel, especially the luminous efficiency, is improved. , better properties, especially higher surface smoothness, are desired.

For example, Patent Literature 1 describes a method for forming a cover layer that improves the smoothness. However, if the design is not properly designed, problems such as uneven light emission may occur due to this, and there is room for improvement.

For example, Patent Document 2 describes a method for forming a high-performance and relatively smooth light extraction film. In some cases, problems that hinder smoothness may occur, and there is room for improvement

In view of such problems of the prior art, the present inventors have solved such problems in a manufacturing method for extracting a plurality of organic EL panels of a desired size from one raw material glass substrate, and have a long life and long life. The inventors have investigated a method for efficiently producing a high-performance organic EL panel, and have completed the present invention.

That is, the present invention provides an organic EL panel including an organic EL element and a sealing film in this order on the element forming surface of a light extraction substrate including a glass substrate, a light extraction film, and a planarizing film in this order from the light emitting surface side. and
The element formation surface consists of an element formation area including a light emitting area corresponding to the organic EL element and a frame area surrounding it in plan view,
The organic EL element is a superimposed portion of a translucent conductive layer, an organic functional layer, and a reflective conductive layer,
The planarizing film layer contains an organic binder, and is surrounded by the light extraction film, the sealing film, and the translucent conductive layer without being exposed to the outside. It relates to an organic EL panel characterized by

In such an organic EL panel of the present invention, since the flattening film is included in the range of the light extraction film in plan view, the electrodes and the like in the power supply path for supplying power to the organic EL elements related to the anode and cathode are not included. It becomes easy to form an electric circuit, and along with this, problems such as uneven light emission can be solved, resulting in a high-performance organic EL panel.

In addition, the above picture frame area is **
From the viewpoint of facilitating the organic EL panel cutting process, which will be described later, it is preferable to have a non-existent continuous circumference without a sealing film. It is preferably composed of only an inorganic component that does not transmit light, and from the viewpoint of ensuring sufficient light extraction performance, the average film thickness is preferably 10 μm or more.

From the viewpoint of ensuring sufficient flatness, the planarizing film preferably has an average film thickness of 5 μm or less. 8 or more is preferable.

In addition, the light-emitting area preferably has a size of 2 mm or more in at least one direction from the viewpoint of obtaining a highly reliable and high-performance organic EL panel, and the element formation region includes a plurality of the light-emitting areas. , the separation width corresponding to the sealing width of the flattening film, and is preferably included at intervals of the width of the separation band having a width of at least 0.5 mm.

Furthermore, the present invention is a method for manufacturing the organic EL panel of the present invention,
At least two or more of the organic EL panels are cut out from one raw glass substrate including the raw glass substrate,
A long-life and high-performance organic EL panel can be efficiently produced with respect to an organic EL panel manufacturing method including a cutting step.

In addition, such a method for manufacturing the organic EL panel of the present invention preferably includes a continuous light extraction film forming step, so that the organic EL panel of the present invention can be produced more efficiently.
In the continuous light extraction film forming step,
The light extraction film is placed on the raw material glass substrate,
an electrode part in a power feeding path for feeding power to the organic EL element, and a plurality of the frame regions, and
A light-outcoupling film is formed in a continuous light-outcoupling film-forming region.

Furthermore, the present invention relates to a light extraction substrate suitable for such an organic EL panel of the present invention, wherein the extraction substrate is a light extraction substrate including a glass base material, a light extraction film, and a planarizing film,
the light extraction film is composed only of an inorganic component and has an average film thickness of 10 μm or more;
The planarizing film is
containing an organic binder,
In a plan view, a flattening film presence region, which is the region in which it exists, is included in the light extraction film presence region, which is the region in which the light extraction film exists,
The average film thickness is 5 μm or less, and
Its refractive index is 1.8 or more.

According to the present invention, an organic EL panel with high reliability, high mechanical strength, and high luminous efficiency can be realized.

1 is a schematic cross-sectional view of an embodiment of an organic EL panel 10 of the present invention; FIG. 2 is a conceptual diagram of another cross section of the organic EL panel 10 of FIG. 1. FIG. 1 is a conceptual cross-sectional view of an embodiment of a light extraction substrate 20 of the present invention, in which an embodiment of an organic EL element 1 to be formed is drawn with a dashed line; FIG. 4 is a conceptual cross-sectional view of an embodiment of an organic EL panel 10 including the light extraction substrate 20 of FIG. 3. FIG. 1 is a conceptual diagram of a cross section of an organic EL panel 10 of Example 1. FIG. 2 is a conceptual diagram of a cross section of an organic EL panel of Comparative Example 1. FIG. 10 is a conceptual cross-sectional view from the light extraction film 23 to the sealing film 9 in the light emitting area 1A of the organic EL panel of Comparative Example 2. FIG. FIG. 10 is a perspective view conceptually showing formation positions of films, layers, elements, and the like formed on a raw glass substrate 200 including a plurality of organic EL panels 10 before a cutting step in Example 2;

As described above, the present invention relates to a light-outcoupling substrate, an organic EL panel including the same, a method for manufacturing the same, and a method for manufacturing the light-outcoupling substrate. Hereinafter, embodiments of the present invention will be described.

[Organic EL panel 10]
FIG. 1 is a conceptual diagram of one cross section of an embodiment of an organic EL panel 10 of the present invention, and FIG. 2 is a conceptual diagram of another cross section of the organic EL panel 10 of FIG.

The organic EL panel 10 of the present invention has a light emitting surface including a light emitting area 1A corresponding to the organic EL element 1, and a sealing film 9 formed to prevent moisture from entering the organic EL element 1. A plate-shaped light source member in which the sealing surfaces are both main surfaces, and the organic EL element 1 is formed on the element forming surface of the light extraction substrate 20, and the element forming surface is the organic EL panel 10. It is the surface on the side of the sealing surface. Here, from the viewpoint of reliability of the organic EL element, the light emitting area 1A preferably has a size of 2 mm or more in at least one direction.

As shown in FIG. 2, the organic EL panel 10 of the present invention includes an electrode portion 10G in a power supply path for supplying power to the organic EL element 1. In FIG. On the non-overlapping portion other than the overlapping portion according to the present invention, which is not included in 1, specifically on the left side thereof, an electrode portion 10G for applying a positive potential to the anode side of the element is drawn, and on the right side thereof. 2, an electrode portion 10G for applying a negative potential to the cathode side of the element is drawn.

As shown in FIGS. 1 and 2, the organic EL element 1, which is the overlapping portion of the translucent conductive layer 6, the organic functional layer 7, and the reflective conductive layer 8, is formed on the planarizing film 24 according to the present invention. , preferably in contact therewith, and such a planarization film 24 is surrounded by the light extraction film 23, the sealing film 9, and the translucent conductive layer 6 without being exposed to the outside. It is one of the features of the present invention that the organic EL panel has high reliability, high mechanical strength, and high luminous efficiency, which are the effects of the present invention.

[Light extraction substrate 20]
FIG. 3 is a conceptual cross-sectional view of one embodiment of the light-outcoupling substrate 20 of the present invention, in which one embodiment of the organic EL element 1 to be formed is drawn with broken lines.

The light-outcoupling substrate 20 according to the present invention is a plate-shaped light-transmitting member whose main surfaces are one main surface that may be the light-emitting surface and the other element formation surface. A glass substrate 21, a light extraction film 23, and a planarizing film 24 are included in this order from to the element forming surface, and the surface of the planarizing film 24 constitutes at least a part of the element forming surface. The surface of the planarizing film 24 corresponds to the planarizing film existing region 24A of the light extraction film 23 in plan view.

The entire surface of the element formation surface is composed only of an element formation region 20A including the light emitting area 1A in plan view and a frame region 20G surrounding the element formation region 20A.

As described above, the element forming region 20A includes the light-emitting areas 1A corresponding to the organic EL elements 1 in plan view. Including in

Here, the separation band 1B is, for example, the surface of the planarizing film 24 shown in FIG. By protecting the flattening film 24 according to the invention with the sealing film 9, a strip having a width of at least 0.5 mm or more corresponding to the sealing width of the flattening film 24 for preventing moisture from entering the device. is the area of

Here, in such a separation band 1B, the surface of the planarizing film 24 is in direct contact with the sealing film 9, but the surface of the planarizing film 24 in the entire region of the separation band 1B is directly in contact with the sealing film 9. There is no need to contact, and it is sufficient if the non-overlapping portion is covered with the sealing film 9 via the translucent conductive layer 6, the organic functional layer 7, and the reflective conductive layer 8, and the organic EL panel of the present invention. 10 includes a plurality of organic EL elements 1, preferably through one or more selected from the group consisting of the translucent conductive layer 6 and the reflective conductive layer 8 in such a non-overlapping portion, in plan view The plurality of organic EL elements 1 in the element formation region 20A are electrically connected by one or more methods selected from the group consisting of series and parallel.

FIG. 4 is a conceptual cross-sectional view of an embodiment of the organic EL panel 10 including the light extraction substrate 20 of FIG.

As shown in FIG. 4, the frame region 20G includes a sealing film absent region 20GG in which the sealing film 9 according to the present invention does not exist in plan view. In FIG. 4, the electrode portion 10G for applying a positive potential to the anode side of the element is drawn on the left side, and the electrode portion 10G for applying a positive potential to the anode side of the element is drawn on the right side in FIG. An electrode portion 10G to which a negative potential is applied is drawn.

Also, the sealing film non-existing region 20GG is preferably a non-existing continuous circumference 20GL that is a region that continuously surrounds the element formation region 20A. In FIG. 4, the left and right ends of the single organic EL panel 10 are depicted as if the sealing films 9 are formed on the left and right sides of the sealing film absent region 20GG. is Regarding such left and right sealing films 9, the sealing film 9 on the panel edge side may not be formed. correspond to

Such a light extraction substrate 20 should have an average thickness of 8 mm or less from the viewpoint of making the organic EL panel 10 of the present invention thin and light and imparting bendable or flexible characteristics to the panel. It is preferably 4 mm or less, still more preferably 2 mm or less, and from the viewpoint of handling, it is preferably 0.1 mm or more, more preferably 0.2 mm or more, and still more preferably 0.4 mm or more. .

The light-outcoupling substrate 20 according to the present invention may contain an alkali barrier layer having a function of preventing alkali components that may be contained in the glass substrate 21 from penetrating into the organic EL element 1. From the viewpoint of capturing positively charged alkali ions, such an alkali barrier layer is preferably an oxide containing a bond dissociation point of negatively charged oxygen, and is preferably colorless and transparent. From the viewpoint of efficiency, the refractive index is desirably about 1.5 to 2.0, which is equal to or higher than that of the glass substrate 21. In addition, cracks do not occur and the light extraction substrate 20 has sufficient strength. Furthermore, it is desirable that the film can be formed continuously and without gaps by a simple method. From this point of view, a layer containing an amorphous silica-based film is preferable.

[Glass substrate 21]
The glass substrate 21 according to the present invention is a main member constituting the light extraction substrate 20. Preferably, a plurality of glass substrates 21 are included in the raw glass substrate 200, and for the same reason as described above, the average thickness of the glass substrate 21 is , preferably 8 mm or less, more preferably 4 mm or less, still more preferably 2 mm or less, and from the viewpoint of handling, it is preferably 0.1 mm or more, more preferably 0.2 mm or more, and still more preferably is 0.4 mm or more.

Such a glass substrate 21 may be chemically strengthened from the viewpoint of improving the strength against cracking when the glass is made thin and making it a panel that can withstand practical use. It is preferable that the end face is treated, and as for the structure, there is no problem not only with a single layer but also with a multi-layer. A treatment layer or a coating film may be formed on the surface of .

As described above, the raw glass substrate 200 includes a plurality of the glass substrates 21 according to the present invention. can be manufactured, and preferably, a plurality of organic EL panels 10 are cut out by a cutting process described later. Such cutting is carried out on the raw material glass substrate 200, the light extraction film 23, the planarizing film 24, the translucent conductive layer 6, the organic functional layer 7, the reflective conductive layer 8, the sealing film 9, and the film according to the present invention. It is possible between and after any steps such as sequentially forming the components included in the power supply path and forming the OC layer, but from the viewpoint of easily and inexpensively manufacturing a large number of organic EL panels 10, preferably , after forming the light-outcoupling film 23, more preferably after forming the light-outcoupling film 23 on the entire one main surface of the raw glass substrate 200, still more preferably after forming the flattening film 24, particularly preferably after forming the light-outcoupling film 23 and From the viewpoint of suppressing reliability deterioration due to stress generated due to temperature change based on the difference in coefficient of linear expansion from the planarizing film 24, after forming a plurality of planarizing films 24 separated from each other, the sealing film 9 is most preferable. After the formation, a plurality of organic EL panels 10 are cut out as a cutting step according to the present invention, which will be described later. After that, it is preferable to individually form an OC layer on each organic EL panel 10, and more preferably, It is to form an OC layer by using an OCF, which will be described later, as an adhesive film layer.

[Light extraction film 23]
The light-outcoupling film 23 according to the present invention has a function of improving the light-outcoupling efficiency by changing the light-outgoing direction at interfaces with different refractive indices, either alone or in combination with films or layers adjacent thereto. , which is a film that constitutes a light extraction structure, and is preferably applied to the light extraction film existing region 23A on the element formation surface side of the glass substrate 21 with a material consisting only of an inorganic component, for example, glass frit, preferably with an average It is formed as a film having a film thickness of 10 μm or more.

Here, the light extraction structure described above is used to radiate the light generated inside the organic EL element 1, particularly inside the organic functional layer 7, which will be described later, from the light emitting area 1A of the light emitting surface to the outside. It is a structure for making a panel with high luminance, that is, a panel with high luminous efficiency by bringing the ratio of the light emitted to close to 1, that is, by increasing the ratio of extracted light, that is, by increasing the “light extraction” efficiency. Specifically, when light enters a low refractive index medium (for example, a normal glass plate) from a high refractive index medium (for example, the inside of the organic EL element 1), the total reflection that occurs at the interface with the different refractive index is It is a structure or the like for reducing by changing the emission angle of light.

In addition, such a "light extraction structure" is not only derived from the light extraction film 23 according to the present invention, but also includes a so-called OCF (out coupling film) disposed on one main surface of the light extraction substrate 20. It is preferable to utilize an OC layer including, for example, one or more layers selected from the group consisting of an adhesive film layer and a resin coating layer.

Such a light extraction film 23 has an uneven shape such as a pyramid shape, a microlens shape, or a moth-eye shape on the side opposite to the glass substrate from the viewpoint of reducing total reflection by changing the light emission angle. However, from the viewpoint of improving the reliability and crest efficiency of the present invention while ensuring the surface smoothness of the planarizing film 24 of the present invention simply, inexpensively, and reliably, Contains fine particulate portions with relatively smooth surfaces and different refractive indices, or contains crystal grain boundaries with a large light scattering effect, for example, contains voids where the refractive index is substantially 0, refractive index is preferably 1 or more and 3 or less, a first glass material and a second glass material dispersed in the first glass material and having a different refractive index It is also preferable to use a film containing a glass material. A second glass material having a higher melting point than the first glass material is added to the first glass material as a matrix to impart a scattering effect and at the same time, a high It is also possible to raise the crystallization temperature of the matrix due to the effect of suppressing crystallization of the matrix material at the interface of the melting point material particles and bake it at 500 ° C. or less to maintain smoothness and form a film in which a small amount of matrix crystallites is formed. preferable.

In such a case, for example, both the first glass material and the second glass material are preferably Bi ₂ O ₃ —B ₂ O ₃ —SiO ₂ —ZnO based glass, which is inexpensive and Excellent transparency, and more preferably, with such a glass composition, the total proportion of SiO ₂ and B ₂ O ₃ in the second glass material is greater than the total proportion in the first glass material, and The ratio of Bi ₂ O ₃ in the second glass material is made smaller than the ratio in the first glass material, and the second glass material is simply and inexpensively made of a material having a melting point higher than that of the first glass material. can be

More preferably, the composition of the Bi ₂ O ₃ -B ₂ O ₃ -SiO ₂ -ZnO-based glass is 0 to 15 wt % SiO ₂ , 0 to 15 wt % B ₂ O ₃ , and 0 to 15 wt % Bi ₂ O ₃ is 65 to 90 wt %, ZnO is 0 to 20 wt %, and each of Al ₂ O ₃ , BaO, and ZrO is in the range of 0 to 10 wt %. The light extraction film 23 is excellent in efficiency and optical properties.

[Planarization film 24]
The flattening film 24 according to the present invention has a smooth surface that constitutes at least a part of the element forming surface, and the planarizing film 24 according to the present invention is formed on, preferably in contact with, the smooth surface. By forming the organic EL element 1, it is a film that has a function of securing the characteristics of the element and the panel, especially the luminous efficiency and reliability, and the presence of a planarizing film on the element formation surface side of the light extraction film 23 A flattening film constituent material containing an organic binder that can be easily formed in the region 24A and that can sufficiently ensure the surface smoothness of the smooth surface, and that contains the organic binder to allow moisture to permeate. Preferably, the planarizing film 24 alone has a light scattering property by using a planarizing film constituent material containing an organic binder having properties, and the material cost is reduced while ensuring sufficient surface smoothness as the light scattering planarizing film 24. from the viewpoint of suppressing the average film thickness, the film is preferably formed as a film having an average film thickness of 1 μm or more and 5 μm or less, more preferably 3 μm or less.

The flattening film 24 has its entire periphery, that is, its entire surfaces such as both main surfaces and four side surfaces thereof, by the light extraction film 23 , the sealing film 9 , and the translucent conductive layer 8 . One of the characteristics of the present invention is that it is surrounded without being exposed to the outside, that is, it is not in contact with anything other than the light extraction film 23, the sealing film 9, and the translucent conductive layer 8. With this feature, it is possible to effectively achieve the effect of high reliability while ensuring the effect of high luminous efficiency according to the present invention.

The surface smoothness of such a planarizing film 24 is preferably 5 nm or less, more preferably 1 nm or less.

The flattening film presence region 24A is included in the light extraction film presence region 23A in a plan view based on the features of the present invention described above, and the light emitting area 1A, which is also a region in contact with the organic EL element 1, is included in the planarization film presence region 24A. including the element forming region 20A.

The organic material constituting the organic binder preferably has a relatively low viscosity from the viewpoint of easily ensuring the surface smoothness and from the viewpoint of further improving the high reliability of the present invention. It is a photocurable resin that can easily obtain good surface smoothness by being applied as a liquid of and then cured. Forming is preferred.

When the planarizing film 24 is the light-scattering planarizing film 24, the material constituting the planarizing film preferably has a number average particle diameter of 0.05 μm to 3 μm and a refractive index of 1.8 or more. of transparent metal oxide particles.

The number average particle diameter of such transparent metal oxide fine particles is preferably 0.05 μm to 3 μm from the viewpoint of exhibiting preferable light scattering properties, and the materials thereof include Ti, Zr, In, Zn, One or more metal oxides selected from the group consisting of Se and W, or composite metal oxides are preferred.

[Organic EL element 1]
The organic EL device 1 according to the present invention includes a translucent conductive layer 6, an organic functional layer 7, and a reflective conductive layer 8. Between the translucent conductive layer 6 and the reflective conductive layer 8, an organic compound It is a light-emitting device in which an organic functional layer 7 containing a light-emitting layer containing By doing so, it emits light.

The organic EL panel 10 of the present invention is obtained by sequentially forming such an organic EL element 1 and a sealing film 9 on the element forming surface of the light extraction substrate 20 of the present invention.

As a material for forming the translucent conductive layer 6, any material having high translucency and electrical conductivity can be used, but transparent conductive metal oxides are preferable from the viewpoint of reliability and luminous efficiency. , the light-transmitting conductive layer 6 is preferably formed as a light-transmitting conductive layer 6 included in the film of the material including a light-transmitting conductive layer 6-side power supply portion related to the power supply to the light-transmitting conductive layer 6 .

As such a transparent conductive metal oxide, ITO and IZO can be exemplified, and the average thickness thereof is preferably 1 μm or less. can be formed by

The organic functional layer 7 generally has a multilayer structure of, for example, a hole injection layer/hole transport layer/light emitting layer/electron transport layer/electron injection layer from the translucent conductive layer 6 side. A connection layer including a charge generation layer, a charge blocking layer, and the like may be included in addition to the layer of (1).

The material for forming the reflective conductive layer 8 is preferably Al or Ag, which has a high reflectance and is effective in improving brightness. is preferably formed by a vacuum vapor deposition method in which the is more preferred.

[Sealing film 9]
The sealing film 9 according to the present invention prevents the organic EL element 1 including the organic functional layer 7 and the reflective conductive layer 8 from deteriorating when the organic functional layer 7 and the reflective conductive layer 8 come into contact with the atmosphere. It is a film formed over the entire surface of the layer 8 side, ie, including the entire region that becomes the light emitting area 1A when observed from the light emitting surface side, and covering the periphery thereof.

From the viewpoint of imparting sufficient water vapor barrier properties to the layer, examples of the material for such a sealing film 9 include inorganic substances, preferably oxide and/or silicon nitride. The thickness is preferably 0.5 μm or more and 5 μm or less.

[Manufacturing method of organic EL panel 10]
The method for manufacturing the organic EL panel 10 of the present invention includes a step of cutting out at least two or more organic EL panels 10 from one raw glass substrate 200 with respect to the raw glass substrate 200 including the glass substrate 21. Preferably, it includes a continuous light extraction film forming step, which will be described later.

The continuous light-outcoupling film forming step includes a plurality of frame regions 20G, that is, the frame regions 20G of adjacent organic EL panels 10 cut out from the raw glass substrate 200, and continuous across them. , forming the light-outcoupling film 23 in the continuous light-outcoupling film forming region 223A.

Further, the method for manufacturing the organic EL panel 10 of the present invention includes, in order, the step of forming the organic EL element 1 on the element forming surface of the light extraction substrate 20 according to the present invention, the step of forming the sealing film 9, and The cutting step is preferably performed after the step of forming the organic EL element 1 , more preferably after the step of forming the sealing film 9 .

EXAMPLES The present invention will be specifically described below by way of Examples and Comparative Examples, but the present invention is not limited to these Examples.

(Example 1)
FIG. 5 is a conceptual diagram of a cross section of the organic EL panel 10 of Example 1, and the organic EL panel 10 of Example 1 is produced and evaluated.

First, as the glass substrate 21, a glass plate 21 having a refractive index of 1.5, a size of 10 cm×10 cm, and a thickness of 0.7 mm, and a first glass material of Bi ₂ O ₃ —B ₂ O ₃ —SiO ₂ —. A ZnO-based glass frit and a Bi ₂ O ₃ —B ₂ O ₃ —SiO ₂ —ZnO-based glass frit as a second glass material are prepared.

Next, the first glass material and the second glass material are mixed at a weight ratio of 37.5:62.5 to prepare the glass paste of Example 1.

Next, the prepared glass paste was applied to the entire surface of one main surface of this glass plate 21 using a screen printer and a stencil so as to have an average thickness of 20 μm. create.

Next, the glass plate 21 having the glass paste layer formed thereon is held at 120° C. for 60 minutes to dry the glass paste, and then fired in the atmosphere at 420° C. for 60 minutes to obtain a glass plate with the light extraction film 23 attached. 21 is produced.

Next, a light-scattering flattening film 24 is formed on the area of the glass plate 21 with the light-outcoupling film 23, which will be the flattening-film-existing region 24A of 8.5 cm×8.5 cm in the center of the light-outcoupling film 23. For this purpose, an acrylic photosensitive resin (refractive index 1.9) containing _TiO2 fine particles (number average particle diameter 0.1 μm) was applied, dried, and UV-cured to form a translucent light with an average layer thickness of 2 μm. A scattering planarization film 4 is formed.

Thus, the light extraction substrate 20 of Example 1 is produced. The surface of the flattening film existing region 24A of the light extraction substrate 20 of Example 1 has surface smoothness of Ra 1.5 nm.

Subsequently, an ITO layer 6 having an average layer thickness of 120 nm was formed on the light extraction substrate 20 of Example 1 which was heated to 180° C. using a shadow mask so as to have a cross section where the translucent conductive layer 6 exists as shown in FIG. It is formed by the RPD method. This ITO layer 6 is a power supply path for applying a positive potential to the anode side of the element drawn on the left side of FIG. As the anode-side power supply path ITO layer 6 included in , the anode-side power supply path ITO layer 6 that is not continuous with the ITO layer 6 of the overlapped portion according to the present invention, and the negative potential on the cathode side of the element drawn on the right side of FIG. The cathode-side power supply path ITO layer 6 included in the power supply path to be applied includes the cathode-side power supply path ITO layer 6 continuous to the ITO layer 6 of the overlapping portion according to the present invention.

Next, the light extraction substrate 20 after the formation of the ITO layer 6 is introduced into a vacuum heating vapor deposition apparatus, and a shadow mask is used to form the cross section shown in FIG. A forming step is performed.

Specifically, as the organic functional layer 7, a hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer are formed in this order, and further the overlapping portion according to the present invention is formed thereon. A reflective conductive layer 8 and an Al layer 8 having an average layer thickness of 120 nm are formed as the reflective conductive layer 8 continuously on the cathode-side feed path ITO layer 6 described above.

Thus, the organic EL element 1 of Example 1 is produced. In the organic EL element 1 of Example 1, the organic EL element 1 of 8 cm×8 cm is formed in the center of the light extraction substrate 20 of Example 1. FIG.

Finally, a sealing film 9 covering the entire surface of the organic EL element 1 and extending to the anode-side power supply path ITO layer 6 and the cathode-side power supply path ITO layer 6 is formed.

Specifically, as the continuous inorganic sealing film 9, a silicon oxynitride layer (average thickness: 2 μm) and a polysilazane-converted silica layer (average thickness: 2 μm) are sequentially formed by the CVD method from the reflective conductive layer 8 side. .

Thus, the organic EL panel 10 of Example 1 is produced.

In the organic EL element 1 of the organic EL panel 10 of Example 1 manufactured in this way, the inorganic sealing film 9 on the sealing surface is not formed and is exposed, and the anode-side power supply path ITO layer. 6, and a constant current of 3 mA/cm2 is supplied from the outside between the cathode side power supply path ITO layer 6, and the total luminous flux of the organic EL element 1 is measured by a total luminous flux measuring device equipped with an integrating sphere. , the power luminous efficiency (lm/W) is calculated, normalized to 1, and compared with the power luminous efficiencies of Comparative Example 1, Comparative Example 2, and Example 2, which will be described later.

Furthermore, the leakage current value (A) was measured when a voltage of 2 V was applied to the organic EL element 1 of the organic EL panel 10 of Example 1, and the leakage current value was normalized as 1, which will be described later. The leakage current values of Comparative Example 1, Comparative Example 2, and Example 2 are compared.

(Comparative example 1)
FIG. 6 is a conceptual diagram of the cross section of the organic EL panel of Comparative Example 1, and the organic EL panel of Comparative Example 1 was produced and evaluated.

As Comparative Example 1, the glass paste layer formed on the entire surface of one main surface of the glass plate 21 in Example 1 was replaced with the glass paste layer formed on the region to be the flattening film existing region 24A in Example 1. An organic EL panel of Comparative Example 1 is produced in the same manner as in Example 1.

The normalized power luminous efficiency of the organic EL element 1 of the organic EL panel of Comparative Example 1 manufactured in this manner is 0.6, and the normalized leakage current value is 100.

(Comparative example 2)
FIG. 7 is a conceptual cross-sectional view from the light extraction film 23 to the sealing film 9 in the light emitting area 1A of the organic EL panel of Comparative Example 2, and the organic EL panel of Comparative Example 2 was produced and evaluated.

Comparative Example 2 is the same as Example 1, except that an inorganic carbonate is used as a foaming agent instead of the second glass material in Example 1, and the light-scattering flattening film 24 in Example 1 is not formed. Then, as shown in FIG. 7, an organic EL panel of Comparative Example 2 is manufactured in which air bubbles are contained in the light extraction film 23 .

The normalized power luminous efficiency of the organic EL element 1 of the organic EL panel of Comparative Example 2 manufactured in this manner is 0.2, and the normalized leakage current value is 10,000.

(Example 2)
FIG. 8 is a perspective view conceptually showing the formation positions of films, layers, elements, etc. formed on a raw glass substrate 200 including 20 organic EL panels 10 before the cutting step in Example 2. The organic EL panel 10 of Example 2 is produced and evaluated.

As Example 2, instead of the glass substrate 21 in Example 1, 20 glass substrates 21 in Example 1 were used as raw glass substrates 200, which had a refractive index of 1.5 and a size of 40 cm×50 cm. In Example 1, the glass plate 200 with a thickness of 0.7 mm is used. Instead of the light-scattering planarizing film 24 formed on the region where the planarizing film exists, 20 planarizing film existing regions 24A are formed so that the organic EL panel 10 having the same shape as the organic EL panel 10 of Example 1 can be cut out. 20 light-scattering planarization films 24 are formed on the region, and the ITO layer 6, the organic functional layer 7, the reflective conductive layer 8, and the sealing film 9 are formed, and furthermore, the present Twenty organic EL panels of Example 2 are produced in the same manner as in Example 1, except that the cutting process according to the invention is performed after the sealing film 9 is formed.

The normalized power luminous efficiency of the organic EL element 1 of the organic EL panel of Example 2 manufactured in this manner is 0.95, and the normalized leakage current value is 2.

(summary)
Compared to the organic EL devices 1 of Comparative Examples 1 and 2, the organic EL device 1 of Example 1 has a larger normalized power luminous efficiency due to the effects of the present invention, and a normalized leakage current value smaller than the effects of the present invention. .

This is because the organic EL element 1 of Comparative Example 1 has a thin portion of the light-transmitting conductive layer 6, which is depicted by x in FIG. As shown in FIG. 5, in the organic EL element 1 of Example 1, the thickness of the translucent conductive layer 6 is maintained, and the electrical resistance of the power feed path is reduced. This is thought to be caused by

In addition, in the organic EL device 1 of Comparative Example 2, as shown in FIG. However, since it is formed along the depressions derived from bubbles, the light-transmitting conductive layer 6 and the reflective conductive layer 8 are close to each other, which is considered to be caused by the occurrence of leakage current and dark spots. In the organic EL element 1 of Example 1, as shown in FIG. It is believed that this is because the layer 8 is smooth, which suppresses leakage current and dark spots.

The organic EL element 1 of Example 2 has substantially the same normalized power luminous efficiency and normalized leakage current value as the organic EL element 1 of Example 1, and Example 2 is as excellent as Example 1. A large number of organic EL panels 10 having such characteristics can be efficiently manufactured.

10. Organic EL panel 10G. electrode part 1 . Organic EL element 1A. Light emitting area 1B. Divider 6 . translucent conductive layer 7 . organic functional layer 8 . reflective conductive layer 9 . Sealing film 200 . Raw glass substrate 223A. Continuous light extraction film formation region 20 Light extraction substrate 20A . Element formation region 20G. Frame area 20GG. Sealing film absent region 20GL. Nonexistent continuous lap 21 . glass substrate 23 . Light extraction film 23A . Light extraction film existing region 24 . The planarizing film 24A. Area where planarization film exists

Claims (7)

An organic EL panel comprising an organic EL element and a sealing film in order on an element formation surface of a light extraction substrate including a glass substrate, a light extraction film, and a planarizing film in order from the light emitting surface side,
The element formation surface consists of an element formation area including a light emitting area corresponding to the organic EL element and a frame area surrounding it in plan view,
The organic EL element is a superimposed portion of a translucent conductive layer, an organic functional layer, and a reflective conductive layer,
The planarizing film contains an organic binder, and is surrounded by the light extraction film, the sealing film, and the translucent conductive layer without being exposed to the outside. Characteristic organic EL panel. the frame region has a non-existent continuous circumference where no sealing film exists, and
wherein the light extraction film is composed only of an inorganic component, and
2. The organic EL panel according to claim 1, wherein the average film thickness is 10 [mu]m or more. Regarding the planarization film,
The average film thickness is 5 μm or less, and
3. The organic EL panel according to claim 1, which has a refractive index of 1.8 or more. The organic EL panel according to any one of claims 1 to 3,
The light emitting area has a size of 2 mm or more in at least one direction, and
The organic EL panel, wherein the element formation region includes the plurality of light emitting areas at intervals equal to the width of a separation band having a width of at least 0.5 mm. A method for manufacturing an organic EL panel according to any one of claims 1 to 4,
At least two or more of the organic EL panels are cut out from one raw glass substrate including the raw glass substrate,
A method for manufacturing an organic EL panel, including a cutting step. The light extraction film is placed on the raw material glass substrate,
an electrode part in a power feeding path for feeding power to the organic EL element, and a plurality of the frame regions, and
forming a light-outcoupling film in a continuous light-outcoupling film-forming region;
including a continuous light extraction film forming step;
A method for manufacturing an organic EL panel according to claim 5 . A light extraction substrate comprising a glass substrate, a light extraction film, and a planarizing film,
the light extraction film is composed only of an inorganic component and has an average film thickness of 10 μm or more;
The planarizing film is
containing an organic binder,
In a plan view, a flattening film presence region, which is the region in which it exists, is included in the light extraction film presence region, which is the region in which the light extraction film exists,
The average film thickness is 5 μm or less, and
A light extraction substrate having a refractive index of 1.8 or more.

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