WO2013027487A1

WO2013027487A1 - Organic light-emitting panel, and method for producing same

Info

Publication number: WO2013027487A1
Application number: PCT/JP2012/066520
Authority: WO
Inventors: 吉田　綾子
Original assignee: パイオニア株式会社
Priority date: 2011-08-24
Filing date: 2012-06-28
Publication date: 2013-02-28
Also published as: WO2013027278A1

Abstract

An organic light-emitting panel containing a resin layer, an organic EL element, which has a laminate structure comprising an organic functional layer and a first and second electrode sandwiching the organic functional layer, and a barrier film disposed between the resin layer and the organic EL element and for inhibiting deterioration promotion substances from entering into the organic EL element, wherein the barrier film contains a high transmittance part having high transmittance with regard to the deterioration promotion substances, and the high transmittance part is localized in the barrier film. Additionally, a method for producing said organic light-emitting panel.

Description

Organic light emitting panel and method for manufacturing the same

The present invention relates to an organic light-emitting panel including an organic EL element having an organic multilayer structure and a method for manufacturing the same.

An organic light emitting panel such as an organic EL panel generally includes an organic EL element having an organic multilayer structure on a substrate and a sealing can made of glass or metal so as to cover the organic light emitting element. It has a structure with a desiccant between it and the can. Also, in order to seal the organic light emitting element, a sealing plate is provided on the outside of the panel in place of the sealing can, and the organic light emitting element is sealed to prevent moisture and moisture from entering the element portion from the outside. Some have a structure in which an adhesive layer is embedded between the plates.

In an organic light emitting panel using a resin layer as a substrate, there are advantages that an organic light emitting element can be formed thin and lightweight, and a flexible panel can be produced. However, the moisture-proof performance of the resin substrate is inferior to that of the glass substrate. Therefore, there is a drawback that the organic light-emitting element is deteriorated due to the penetration of moisture through the resin substrate into the organic light-emitting element. In order to cope with moisture intrusion through the resin substrate, a barrier film for moisture prevention is usually formed between the resin substrate and the organic light emitting element.

However, even if a barrier film is formed, for example, as shown in FIG. 1, if a defect such as a pinhole 3 exists in the barrier film 2 on the resin substrate 1, the moisture 4 is organically removed from the pinhole 3 over time. The light enters the light emitting element, and the deterioration of the portion progresses, and a non-light emitting portion called a dark spot appears. Moisture that has entered the organic light emitting element diffuses inside the organic light emitting element and spreads the deteriorated portion with time, so that the dark sport gradually expands.

JP 2008-277209 A JP 2009-110864 A

In an illuminating device provided with such an organic light-emitting panel, the organic light-emitting panel should be replaced because the organic light-emitting panel can emit light even though the above-described dark spots start to occur and the organic light-emitting element is deteriorated. There was a problem that the time was not always clear.

There are devices disclosed in Patent Documents 1 and 2 as devices for visually notifying the replacement timing of the organic light emitting panel. However, the devices disclosed in Patent Documents 1 and 2 have an indicator portion indicating the replacement time of the panel independently of the light emitting portion of the panel body, and the indicator portion has an organic multilayer structure different from the light emitting portion. However, since the driving conditions are different, there is a problem that the replacement time of the panel accompanying the progress of deterioration of the organic light emitting panel is not always properly expressed.

Thus, the problem to be solved by the present invention is to provide an organic light emitting panel capable of easily and appropriately informing the organic light emitting panel replacement time, and a method for manufacturing the same, in which the above-mentioned problem is given as an example. It is an object of the present invention.

An organic light-emitting panel according to a first aspect of the present invention includes a resin layer, an organic EL element having a laminated structure including an organic functional layer and first and second electrodes sandwiching the organic functional layer, the resin layer, and the organic An organic light-emitting panel including a barrier film disposed between the EL element and preventing the deterioration promoting substance from entering the organic EL element, wherein the barrier film has a high transmittance with respect to the deterioration promoting substance. The high transmissive part is localized in the barrier film.

According to a seventh aspect of the present invention, there is provided a method for manufacturing an organic light emitting panel, comprising: forming an organic EL element having a laminated structure including an organic functional layer and first and second electrodes sandwiching the organic functional layer; Forming a barrier film for preventing the deterioration-promoting substance from entering the device between the resin layer and the organic EL device, and manufacturing the organic light-emitting panel. On the other hand, the method has a step of locally forming a high transmission portion having a high transmittance in the barrier film.

It is sectional drawing which shows the penetration | invasion of the water | moisture content through a resin layer. It is sectional drawing which shows the organic EL panel of a bottom emission type as an Example of this invention. It is a flowchart which shows the manufacturing method of the organic electroluminescent panel of FIG. It is sectional drawing which shows the example which laminated | stacked the barrier film and the resin layer on the resin substrate. It is an external view which shows the pinhole formed in the barrier film of the organic electroluminescent panel of FIG. It is an external view which shows the form of the dark spot of the organic electroluminescent panel by the pinhole of FIG. It is a graph which shows the size expansion characteristic of the dark spot according to time passage. It is sectional drawing which shows an organic electroluminescent panel as another Example of this invention. It is sectional drawing which shows the top emission type organic electroluminescent panel as another Example of this invention. It is sectional drawing which shows the top emission type organic electroluminescent panel as another Example of this invention. It is sectional drawing which shows the film sealing type organic electroluminescent panel as another Example of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a cross section of a bottom emission type organic EL panel for a lighting apparatus to which the present invention is applied, and FIG. 3 shows a flowchart showing the manufacturing method thereof. FIG. 2 shows a cross section in a direction perpendicular to the longitudinal direction of the longitudinal resin substrate 11.

For example, as shown in FIG. 3, the organic EL panel includes a barrier film 12 (step S 1), a pinhole 13 (step S 2), a first electrode 14 (step S 3), and an organic functional layer 15. Formation (step S4), formation of the second electrode 16 (step S5), formation of the inorganic layer 17 (step S6), formation of the sealing film 18 (step S7), and attachment of the sealing substrate 19 (step S8) Are manufactured in this order.

In this organic EL panel, a transparent (including translucent) barrier film 12 is formed on a transparent (including translucent) resin substrate 11 so as to cover the entire surface. As a material of the resin substrate 11, for example, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), polyarylate (PAR), and polyethersulfone (PES) can be used. The material of the barrier film 12 is made of an inorganic material such as SiN, SiON, SiOx, Al ₂ O ₃ , for example. The barrier film 12 can be formed on the resin substrate 11 using a film forming method such as CVD, sputtering, or vacuum deposition. The film thickness of the barrier film 12 is, for example, 100 nm.

In addition, as shown in FIG. 4, the barrier film 12 may raise the reliability of moisture-proof performance by laminating | stacking the barrier film 12a and the resin layer 12b in multiple layers.

Also, a pinhole 13 is formed in the barrier film 12 that acts as an indicator that indicates the replacement time of the panel. The pinhole 13 is a high transmission part having a high transmittance with respect to deterioration promoting substances such as moisture and air. The pinhole 13 of this embodiment obtains high transmittance by penetrating the barrier film 12 in the stacking direction of the organic EL element 20 described later.

The pinhole 13 is localized in the barrier film 12. In other words, the pinhole 13 is formed at the end of the light emitting region of the organic EL element 20 in the barrier film 12. Further, when viewed from the outer surface of the resin substrate 11, the pinholes 13 are formed at both ends in the direction orthogonal to the longitudinal direction as shown in FIG. In this embodiment, the pinhole 13 has a significant two-dimensional pattern having a shape representing a star mark 13a and a letter 13b "Please replace", as shown in FIG. The size of the pinhole 13 is, for example, 100 μm.

The pinhole 13 can be formed, for example, by etching the barrier film 12 with plasma using a patterned resist and using other methods such as lift-off.

A transparent first electrode 14 is formed on the barrier film 12. The first electrode 14 is formed by depositing and forming a transparent conductive film on the barrier film 12 with a light transmissive material such as ITO or IZO, and patterning using a photolithography technique.

Further, an organic functional layer 15 is formed on the barrier film 12 so as to cover the first electrode 14, and a second electrode 16 made of metal is laminated on the organic functional layer 15. The organic functional layer 15 has, for example, a multilayer structure of a hole injection / transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in order from the first electrode 14 side, and is formed by a dry method such as a vacuum evaporation method. In addition, it can be formed by a wet method such as an inkjet method or printing. The second electrode 16 can be formed by a vacuum deposition method, and Al or Ag having high light reflection efficiency can be used as the metal material.

The portion composed of the first electrode 14, the organic light emitting layer 15, and the second electrode 16 is the organic EL element 20. In the example of FIG. 2, the first electrode 14 is an anode and the second electrode 16 is a cathode. The light emitting region described above is a range for patterning the first electrode 14, and the pinhole 13 is formed at a position corresponding to the end of the first electrode 14.

The outer periphery of the organic EL element 20, that is, the second electrode 16 is covered with the inorganic layer 17. The inorganic layer 17 can be formed of the same inorganic material as that of the barrier film 12 using the same film formation method.

A desiccant and an adhesive are applied onto the inorganic layer 17 and the surrounding barrier film 12, and cured to form a sealing film 18. As the adhesive, a thermosetting epoxy resin adhesive or an ultraviolet curable acrylic adhesive can be used.

A sealing substrate 19 is further attached on the sealing film 18. As the sealing substrate 19, metal, glass, or a resin with a moisture-proof function added can be used.

In the organic EL panel having such a configuration, light is generated in the organic functional layer 15 by passing a driving current from the first electrode 14 toward the second electrode 16 through the organic EL element 20, and the light is generated by the first electrode 14, It is discharged to the outside through the barrier film 12 and the resin substrate 11.

FIG. 6 (a) shows the appearance of the panel 21 in the initial state, and the pinhole 13 cannot actually be visually observed, but is shown thin so that the shape thereof can be understood for easy understanding. Over time, deterioration promoting substances such as moisture and air enter from the outer surface of the resin substrate 11, the interface between the resin substrate 11 and the barrier film 12, or the side portions of the resin substrate 11 and the barrier film 12. Degradation promoting substances include the molecular level. The deterioration promoting substance gradually enters the pinhole 13 and reaches the organic EL element 20 through the pinhole 13. Due to the deterioration promoting substance, the portion of the organic EL element 20 corresponding to the pinhole 13 causes a light emission deterioration portion called a dark spot due to deterioration. In the light emission deterioration portion, for example, non-light emission, light emission becomes dark, or conversely, the light emission color changes. Such a light emission deterioration portion of the organic EL element 20, that is, a dark spot, expands with time. Therefore, when it is time to replace the panel, as shown in FIG. 6 (b), the star mark 13a of the pinhole 13 and the letter 13b "Please replace" are visible (for example, a star mark with a size of several millimeters). ) Appears as a dark spot. The appearance of the star mark 13a and the letter “Replace” 13b informs the user that it is time to replace the light-emitting panel. When the use is continued without replacing the light-emitting panel even after the replacement time, a dark spot 22 appears in an area (referred to as an effective area) other than both ends of the panel as shown in FIG. The dark spot 22 in this effective area is penetrated into the organic EL element 20 from the pinhole existing as a defect at any position within the range of the barrier film 12 corresponding to the effective area. This is a result of further deterioration. Therefore, since the dark spot due to the pinhole 13 is generated before the dark spot 22 is generated in the region of the barrier film 12 corresponding to the effective area, the panel replacement time is notified visually and appropriately by the pinhole 13. Can do. That is, the replacement of the panel can be notified before the dark spot appears in the effective area and the quality of the lighting device deteriorates.

Further, by making the pinhole 13 into a two-dimensional pattern shape such as “please replace” which is significant and visually recognizable, the dark spot 22 of the light emitting element 20 corresponding to the pattern has a transparent barrier layer 12 and a resin substrate 11. It is possible to visually recognize from the outside through this, and thereby it becomes possible to act as a deterioration indicator.

Further, since the pinhole 13 is arranged at the end of the panel, the deterioration promoting substance that has entered from the side surface of the panel enters the pinhole 13, so that the expansion of the dark spots in the effective area can be suppressed.

The appearance timing of the dark spot indicating the panel replacement time by the pinhole 13 can be set by the position of the barrier film 12 for producing the pinhole 13. The size expansion characteristic of the dark spot due to the pinhole 13 over time varies depending on the distance from one end of the barrier film 12 to the pinhole 13. For example, as shown in FIG. 7, as can be seen from the enlarged characteristics when the distance from one end to the pinhole 13 is 2 mm, 4 mm, and 6 mm, the size of the dark spot due to the pinhole 13 becomes shorter as the distance is shorter. Since it expands, the timing of the appearance of the dark spot can be set at the position of the barrier film 12 where the pinhole 13 is formed. Therefore, the panel replacement time can be appropriately notified by setting this position according to the deterioration rate of the organic EL element. For example, if the pinholes 13 are formed at distances of 2 mm, 4 mm, and 6 mm from one end of the barrier film 12 to the pinholes 13, the progress of deterioration of the organic EL element can be visually shown. Furthermore, this timing can be adjusted not only according to the position of the pinhole 13 but also according to the type and thickness of each of the barrier film 12 and the resin substrate 11.

In the above-described embodiment, the organic EL element 20 has no difference between the end portion of the light emitting region (corresponding to the formation region of the pinhole 13 of the barrier film 12) and the other effective area. As shown in FIG. 8, a dividing portion 15 a may be provided in the organic functional layer 15 at the boundary position between the end portion of the light emitting region and the effective area. This is because the moisture diffusion coefficient of the organic functional layer 15 is larger than that of the other layers so that moisture penetration from the pinhole 13 does not affect the effective area from the end. As the division, only at least one layer of the organic functional layer 15 may be divided or made thin.

Further, the significant two-dimensional pattern shape by the pinhole 13 is not limited to the star shape and the character shape shown in the embodiment, and other shapes and other characters may be used in the present invention.

Furthermore, each material of the resin substrate 11, the barrier film 12, the first electrode 14, the organic functional layer 15, the second electrode 16, the inorganic layer 17, the sealing film 18, and the sealing substrate 19 in each of the above-described embodiments is as described above. The conditions such as the formation method and thickness thereof are not particularly limited.

The “resin layer” in the claims is not only the resin substrate 11 but also the resin layer 12b when the barrier film 12 is a laminated film of the barrier film 12a and the resin layer 12b as shown in FIG. good. Further, when a laminated structure of a barrier film and a resin layer is used as a sealing film covering an organic EL element in a panel using a glass substrate, the same effect can be obtained even if a pinhole is formed in the barrier film. it can.

In each of the above-described embodiments, a bottom emission type organic EL panel that emits light from a bottom substrate such as the resin substrate 11 for forming the organic EL element 20 is shown. However, the present invention is a sealing substrate. The present invention can be applied to a top emission type organic EL panel that emits light from the side.

FIG. 9 shows a top emission type organic EL panel as another embodiment of the present invention. In this top emission type organic EL panel, an insulating film 32 is formed on a metal substrate 31 so as to cover the entire surface. The metal substrate 31 is made of stainless steel, for example. The insulating film 32 is a resin layer, and examples of the material thereof include a coating film having insulating properties such as epoxy, acrylic, polyimide, sol-gel, and polysilazane. A barrier film 33 is formed on the insulating film 32 so as to cover the entire surface thereof. Since the barrier film 33 has a pinhole 34 and is the same as the barrier film 12 of the bottom emission type organic EL panel of FIG. 2, description thereof is omitted here. On the barrier film 33, an organic EL element 38 is formed in which a first electrode 35 made of metal, an organic functional layer 36, and a second electrode 37 of a transparent electrode are stacked in that order. The first electrode 35 can be formed by a vacuum deposition method, and Al or Ag having high light reflection efficiency can be used as the metal material. The second electrode 37 is formed by depositing and forming a transparent conductive film on the organic functional layer 36 with a light-transmitting material such as ITO or IZO, and patterning using a photolithography technique. The organic functional layer 36 is the same as the organic functional layer 15 of the bottom emission type organic EL panel of FIG. The outer periphery of the organic EL element 38, that is, the second electrode 37 is covered with an inorganic layer 39. The inorganic layer 39 is a barrier film, and can be formed of the same inorganic material as that of the barrier film 12 using the same film forming method as the inorganic layer 17 described above.

A transparent (including translucent) desiccant and an adhesive are applied on the inorganic layer 39 and the surrounding barrier film 33, and cured to form a sealing film 40 as a resin layer. . A transparent sealing substrate 41 is further affixed on the sealing film 40. As the sealing substrate 41, glass or a resin having a moisture-proof function can be used.

In the top emission type organic EL panel having such a configuration, light is generated in the organic functional layer 36 by causing a driving current to flow from the first electrode 35 toward the second electrode 37 through the organic EL element 20, and the light is generated. Is released to the outside through the second electrode 37, the inorganic layer 39, the sealing film 40 and the sealing substrate 41.

By forming a pinhole 34 that acts as an indicator indicating the deterioration of the organic EL element 38 in the barrier film 33, when a deterioration promoting substance such as moisture or air enters the pinhole 34 over time, the pinhole 34 is dealt with. A dark spot is generated in the portion of the organic EL element 38 that has been subjected. The dark spot due to the pinhole 34 is generated before the dark spot is generated in a portion other than the portion of the organic EL element 38 corresponding to the pinhole 34 of the barrier film 33, and the dark spot expands with time. By generating dark spots by the pinholes 34, it is possible to easily and appropriately notify the panel replacement time.

In the top emission type organic EL panel described above, the pinhole 34 is provided in the barrier film 33, but a structure in which the pinhole 42 is formed in the inorganic layer 39 as shown in FIG. In the organic EL panel having the structure of FIG. 10, when a deterioration promoting substance such as moisture enters the pinhole 42 from the side surface of the panel through the sealing film 40 with time, the organic EL element corresponding to the pinhole 42. A dark spot is generated in the portion 38. In addition, the structure in which the pinhole is provided in the inorganic layer is not limited to the top emission type organic EL panel, but may be applied to the bottom emission type organic EL panel shown in FIG.

In the case of a top emission type organic EL panel, since the light generated by the organic EL element is emitted to the sealing substrate side as described above, the first electrode 35, the insulating layer 32, and the barrier film 33 are transparent. There is no need. Further, although the metal substrate 31 is provided, a glass substrate or a resin substrate may be used instead.

Further, in each of the above-described embodiments, the

pinholes

13, 34, and 42 that are through holes are shown as the high transmission portions having a high transmittance with respect to the deterioration promoting substance, but the high transmission portions pass through the deterioration promoting substance. In this case, the through hole such as a pinhole is not necessarily required, and it may be a portion that penetrates the deterioration promoting substance and proceeds toward the organic EL element. Further, the high transmission part may be a part where the barrier film is reduced in thickness because the barrier film is thinner than the other part.

In each of the above-described embodiments, the sealing film and the sealing substrate are shown as the sealing structure, but the present invention is not limited to this. For example, as shown in FIG. 11, a structure in which the sealing film 18 and the sealing substrate 19 of FIG.

The organic light emitting panel and the manufacturing method of the present invention can be applied to an organic EL image display panel and an organic EL lighting panel, and the organic light emitting panel of the present invention is preferably used for a light emitting device including a lighting device.

As described above, according to the organic light-emitting panel and the method for manufacturing the same of the present invention, the barrier film formed between the resin layer and the organic light-emitting element has a high transmittance with respect to deterioration promoting substances such as moisture. Since the high transmissive portion is localized in the barrier film including the transmissive portion, when a deterioration promoting substance enters the high transmissive portion with time, a dark spot is generated in the element portion corresponding to the high transmissive portion. . The dark spot due to the penetration of the deterioration promoting substance through the high transmission part is generated before the dark spot is generated in the part other than the high transmission part of the barrier film, and the dark spot is enlarged with time. By generating dark spots, it is possible to easily and appropriately announce the panel replacement time.

11

Resin substrate

12, 33

Barrier film

13, 34

Pinhole

14, 35

First electrode

15, 36 Organic

functional layer

16, 37

Second electrode

17, 39

Inorganic layer

18, 40

Sealing film

19, 41

Sealing substrate

20, 38 Organic EL device 22 Dark spot 31 Metal substrate

Claims

A resin layer;
An organic EL element having a laminated structure comprising an organic functional layer and first and second electrodes sandwiching the organic functional layer;
A barrier film that is disposed between the resin layer and the organic EL element and prevents a deterioration promoting substance from entering the organic EL element;
The organic light emitting panel, wherein the barrier film includes a high transmission part having a high transmittance with respect to the deterioration promoting substance, and the high transmission part is localized in the barrier film.
2. The organic light emitting panel according to claim 1, wherein the organic EL element is deteriorated by light emission of a portion corresponding to the high transmission portion of the organic EL element.
3. The organic light-emitting panel according to claim 2, wherein the high transmission part is a pinhole penetrating the barrier film in the stacking direction of the organic EL elements.
4. The organic light emitting panel according to claim 3, wherein the high transmission part is located in a region of the barrier film corresponding to an end of a light emitting region of the organic EL element.
The organic light-emitting panel according to claim 4, wherein a distance from one end of the barrier film to the high transmission part is determined according to a deterioration rate of the organic EL element.
3. The organic light emitting panel according to claim 2, wherein the organic functional layer is divided or thinned at a boundary position between the end of the light emitting region of the organic EL element and the other central region.
Forming an organic EL element having a laminated structure including an organic functional layer and first and second electrodes sandwiching the organic functional layer;
Forming a barrier film for preventing the deterioration promoting substance from entering the organic EL element so as to be positioned between the resin layer and the organic EL element, and a method of manufacturing an organic light-emitting panel,
A method for manufacturing an organic light-emitting panel, comprising: forming a high transmission portion having a high transmittance with respect to the deterioration promoting substance in the barrier film.