CN101847652B - Electroluminescent display panel - Google Patents

Abstract

The invention discloses an electroluminescence display panel, which comprises an active element array substrate, a pixel definition layer, an electroluminescence element layer, an electrode layer and a protective layer. The substrate has pixel electrodes. The pixel definition layer on the substrate has openings. Each opening respectively exposes a pixel electrode. The electroluminescence element layer is located in the opening. Each electroluminescence element layer is respectively located on a pixel electrode. The electrode layer is located on the pixel definition layer and the electroluminescence element layer. A protection layer including a buffer layer, first and second encapsulation films is located on the electrode layer. The buffer layer covers the pixel definition layer and the electroluminescence element layer. The first encapsulation film only partially covers the buffer layer. The first encapsulation film includes an island pattern on the pixel electrode. The second encapsulation film covers the buffer layer and the first encapsulation film.

Description

Electroluminescent Display Panel

technical field

The present invention relates to a display panel, and more particularly to an electroluminescent display panel.

Background technique

With the advancement of display technology, people can make life more convenient with the assistance of display devices. In order to achieve light and thin characteristics of displays, flat panel displays have become the current mainstream.

Among various flat-panel displays, the active matrix electroluminescent display (AMLED) display has the advantages of wide viewing angle, good color contrast effect, light and thin, fast response speed and low cost, so it is very suitable for portable video products. (Notebook computers, PDAs, mobile phones, etc.), especially large display devices such as TVs, etc.

In a general active matrix electroluminescent display, the electroluminescent element is usually covered with a buffer layer, and the buffer layer is sequentially covered with an organic layer and an inorganic layer to prevent moisture or oxygen from contacting the electroluminescent element and causing damage to the element. damage, and planarization of the component surface. However, when forming the buffer layer, the organic layer and the inorganic layer, it is inevitable to generate pinholes in each film layer, so that water vapor and oxygen can contact the electroluminescent element through these pinholes. In addition, because moisture and oxygen in the organic layer are very easy to diffuse to areas other than the pinholes, a large area of the device is often damaged.

Contents of the invention

The invention provides an electroluminescent display panel, which can effectively prevent water vapor and oxygen from greatly diffusing in an organic layer.

The present invention further provides an electroluminescent display panel, which can effectively prevent large-area damage to components.

The invention provides an electroluminescent display panel, which includes an active element array substrate, a pixel definition layer, a plurality of electroluminescent element layers, an electrode layer and a protective layer. The active element array substrate has a plurality of pixel electrodes arranged in an array. The pixel definition layer is disposed on the active element array substrate, wherein the pixel definition layer has a plurality of openings arranged in an array, and each opening respectively exposes one of the pixel electrodes. The electroluminescent element layers are arranged in the opening, and each electroluminescent element layer is respectively arranged on one of the pixel electrodes. The electrode layer covers the pixel definition layer and the electroluminescence element layer. The protective layer covers the electrode layer. The protection layer includes a buffer layer, a first encapsulation film and a second encapsulation film. The buffer layer covers the pixel definition layer and the electroluminescence element layer. The first encapsulation film only partially covers the buffer layer. The first encapsulation film includes a plurality of island-shaped patterns separated from each other, and the island-shaped patterns are located above the pixel electrodes. The second encapsulation film covers the buffer layer and the first encapsulation film.

According to the electroluminescence display panel described in the embodiment of the present invention, the above-mentioned active element array substrate includes a plurality of scanning lines, a plurality of data lines and a plurality of active elements. The active element is electrically connected to the scan line, the data line and the pixel electrode correspondingly, and the scan line, the data line and the active element are covered by the pixel definition layer.

According to the electroluminescent display panel described in the embodiment of the present invention, the water vapor transmission rate (WVTR) of the above-mentioned first encapsulation film is, for example, greater than the water vapor transmission rate of the second encapsulation film.

According to the electroluminescence display panel described in the embodiment of the present invention, the oxygen transmission rate (oxygen transmission rate, OTR) of the above-mentioned first encapsulation film is greater than the oxygen transmission rate of the second encapsulation film, for example.

According to the electroluminescence display panel described in the embodiment of the present invention, the water vapor transmission rate of the above-mentioned first encapsulation film is, for example, between 0.1 g/m ² /day and 100 g/m ² /day, and the second encapsulation film The water vapor transmission rate of the film is, for example, between 1 g/m ² /day and 50 g/m ² /day.

According to the electroluminescence display panel described in the embodiment of the present invention, the oxygen transmission rate of the above-mentioned first encapsulation film is, for example, between 0.1cc/m ² /day and 100c.c./m ² /day, and the second The oxygen transmission rate of the two-encapsulation film is, for example, between 1 c.c./m ² /day and 50 c.c./m ² /day.

According to the electroluminescence display panel described in the embodiment of the present invention, the material of the buffer layer and the second encapsulation film is, for example, an inorganic material, and the material of the first encapsulation film is, for example, an organic material.

According to the electroluminescent display panel described in the embodiment of the present invention, each of the above-mentioned island-shaped patterns is respectively located in one of the openings, for example.

According to the electroluminescent display panel described in the embodiment of the present invention, each of the above electroluminescent element layers includes a light emitting layer, a hole injection layer (hole injection layer, HIL), a hole transport layer (hole transport layer, HTL) and electron Injection layer (electron injection layer, EIL). The light emitting layer is arranged between one of the pixel electrodes and the electrode layer. The hole injection layer is disposed between one of the pixel electrodes and the light emitting layer. The hole transport layer is disposed between the hole injection layer and the light emitting layer. The electron injection layer is arranged between the light emitting layer and the electrode layer.

The present invention further provides an electroluminescent display panel, which includes an active element array substrate, a pixel definition layer, a plurality of electroluminescent element layers, an electrode layer, and a protective layer. The active element array substrate has a plurality of pixel electrodes arranged in an array. The pixel definition layer is disposed on the active element array substrate, wherein the pixel definition layer has a plurality of openings arranged in an array, and each opening respectively exposes one of the pixel electrodes. The electroluminescent element layers are arranged in the opening, and each electroluminescent element layer is respectively arranged on one of the pixel electrodes. The electrode layer covers the pixel definition layer and the electroluminescence element layer. The protective layer covers the electrode layer. The protection layer includes a first encapsulation film. The first encapsulation film includes a plurality of island-shaped patterns separated from each other, and the island-shaped patterns are generally located directly above the pixel electrodes and not located in areas other than directly above the pixel electrodes.

According to the electroluminescence display panel described in the embodiment of the present invention, the water vapor transmission rate of the above-mentioned first packaging film is, for example, between 0.1 g/m ² /day and 100 g/m ² /day.

According to the electroluminescence display panel described in the embodiment of the present invention, the oxygen transmission rate of the above-mentioned first encapsulation film is, for example, between 0.1 cc/m ² /day and 100 c.c./m ² /day.

According to the electroluminescence display panel described in the embodiment of the present invention, the material of the above-mentioned first packaging film is, for example, an organic material.

Based on the above, the present invention arranges each encapsulation film formed by organic materials in each opening of the pixel definition layer, so that these encapsulation films formed by organic materials are not connected to each other, so when moisture and oxygen are released from the film layer When the pinholes enter, the water vapor and oxygen can be prevented from greatly diffusing in the encapsulation film formed by the organic material, thereby reducing the damage of the electroluminescent element.

The following are detailed descriptions and accompanying drawings of the present invention. However, the accompanying drawings are only for reference and auxiliary description, and are not intended to limit the present invention.

Description of drawings

FIG. 1A is a schematic top view of an electroluminescence display panel according to an embodiment of the present invention;

Figure 1B is a schematic cross-sectional view of the electroluminescence display panel drawn along the line I-I' in Figure 1A;

FIG. 2 is a schematic cross-sectional view of an electroluminescent display panel according to another embodiment of the present invention.

Among them, reference signs

10, 20: Electroluminescence display panel 100: Active element array substrate

100a: Pixel electrode 100b: Scanning line

100c: Data line 102: Pixel definition layer

104: Electroluminescent element layer 104a: Light emitting layer

104b: hole injection layer 104c: hole transport layer

104d: Electron injection layer 106: Electrode layer

108: Protective layer 108a: Buffer layer

108b, 108c, 108d, 108e: packaging film 110: opening

Detailed ways

FIG. 1A is a schematic top view of an electroluminescent display panel according to an embodiment of the present invention. FIG. 1B is a schematic cross-sectional view of the electroluminescent display panel along the line I-I' in FIG. 1A. Please refer to FIG. 1A and FIG. 1B at the same time. The electroluminescent display panel 10 includes an active element array substrate 100 , a pixel definition layer 102 , an electroluminescent element layer 104 , an electrode layer 106 and a protection layer 108 . The material of the active device array substrate 100 is, for example, glass, plastic or other suitable materials. The active device array substrate 100 has pixel electrodes 100a arranged in an array. The material of the pixel electrode 100 a is, for example, indium tin oxide (ITO) or indium zinc oxide (IZO). In addition, the active device array substrate 100 also has scan lines 100b, data lines 100c and active devices (not shown for clarity of the drawing). The scan lines 100b and the data lines 100c are perpendicular to each other. The active device is electrically connected to a corresponding scan line 100b, a data line 100c and a pixel electrode 100a. The material of the scan line 100b and the data line 100c is, for example, metal. The active element includes a gate, a gate insulating layer, a channel layer, a source/drain, etc., and the relationship between them is well known to those skilled in the art, and will not be further described here.

The pixel definition layer 102 is disposed on the active device array substrate 100 . The pixel definition layer 102 covers the scan line 100b, the data line 100c and the active device to define a pixel area. The material of the pixel definition layer 102 is, for example, acrylic. The pixel definition layer 102 has an opening 110 . The openings 110 are arranged in an array, and each opening 110 exposes a pixel electrode 100a.

The electroluminescent element layers 104 are disposed in the opening 110 , and each electroluminescent element layer 104 is disposed on a pixel electrode 100 a. The electroluminescence element layer 104 includes a light emitting layer 104a, a hole injection layer 104b, a hole transport layer 104c, and an electron injection layer 104d. The hole injection layer 104b, the hole transport layer 104c, the light emitting layer 104a and the electron injection layer 104d are sequentially stacked on the pixel electrode 100a. The material of each film layer in the electroluminescence element layer 104 can use the material of the known electroluminescence element layer. The light-emitting layer 104 a is, for example, an organic light-emitting layer or an inorganic light-emitting layer, and the material of the organic light-emitting layer is, for example, Alq. The material of the hole injection layer 104 b is, for example, CuPc, the material of the hole transport layer 104 c is, for example, NPB, and the material of the electron injection layer 104 d is, for example, LiF. The formation method of the light emitting layer 104a, the hole injection layer 104b, the hole transport layer 104c and the electron injection layer 104d is, for example, ink-jet printing (IJP). In addition, in other embodiments, an electron transport layer can also be arranged between the electron injection layer 104d and the light emitting layer 104a according to actual needs; a hole blocking layer can be arranged between the light emitting layer 104a and the electron injection layer 104d or the electron transport layer .

The electrode layer 106 is, for example, conformally covering the pixel definition layer 102 and the electroluminescence element layer 104 to serve as a common electrode. The material of the electrode layer 106 is aluminum, for example.

The passivation layer 108 covers the electrode layer 106 . In detail, the protection layer 108 includes a buffer layer 108a, an encapsulation film 108b and an encapsulation film 108c. The buffer layer 108 a is, for example, conformally disposed on the electrode layer 106 to cover the pixel definition layer 102 and the electroluminescence element layer 104 . The material of the buffer layer 108a is, for example, an inorganic material. The encapsulation film 108b only partially covers the buffer layer 108a. In this embodiment, the encapsulation film 108 b is, for example, island-shaped patterns separated from each other, and these island-shaped patterns are disposed in the opening 110 and directly above the pixel electrodes 100 a. In another embodiment, the encapsulation film 108 b may be located on the buffer layer 108 a around the opening 110 in addition to being located in the opening 110 . The material of the encapsulation film 108b is, for example, an organic material, and its water vapor transmission rate is, for example, between 0.1 g/m ² /day and 100 g/m ² /day, while the oxygen transmission rate is, for example, between 0.1 cc/m ^{2 /} day. day to 100c.c./m ² /day. In addition, the encapsulation film 108c covers the buffer layer 108a and the encapsulation film 108b. The material of the packaging film 108c is, for example, an inorganic material, and its water vapor transmission rate is, for example, between 1 g/m ² /day and 50 g/m ² /day, while the oxygen transmission rate is, for example, between 1 c.c./m ² /day to 50c.c./m ² /day. In one embodiment, the water vapor transmission rate of the encapsulation film 108b is, for example, greater than the water vapor transmission rate of the encapsulation film 108c. In one embodiment, the oxygen transmission rate of the encapsulation film 108b is, for example, greater than the oxygen transmission rate of the encapsulation film 108c.

It can be seen from FIG. 1B that since the packaging films 108b formed of organic materials are located in each opening 110 and are not connected to each other, when water vapor and oxygen enter through the pinholes in each film layer, they cannot be packaged. The thin film 108b spreads to other regions, so that the device will not be damaged in a large area.

In particular, in this embodiment, the protective layer 108 is a buffer layer 108a formed of an inorganic material, a packaging film 108b formed of an organic material, and a packaging film 108b formed of an inorganic material. 108c, and in other embodiments, the protective layer may also be composed of a buffer layer 108a and a composite layer formed by alternately stacking multiple organic material layers and multiple inorganic material layers sequentially.

FIG. 2 is a schematic cross-sectional view of an electroluminescent display panel according to another embodiment of the present invention. Please refer to FIG. 2. In this embodiment, the difference between the electroluminescent display panel 20 and the electroluminescent display panel 10 is that in the electroluminescent display panel 20, the protective layer is composed of a buffer layer 108a, an encapsulation film 108b (for example, organic material), encapsulation film 108c (for example, inorganic material), encapsulation film 108d (for example, organic material) and encapsulation film 108e (for example, inorganic material). Of course, in other embodiments, more layers of organic material layers and inorganic material layers can be continuously stacked according to actual needs.

Certainly, the present invention also can have other multiple embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (9)

1. An electroluminescent display panel, characterized in that it comprises: An active element array substrate having a plurality of pixel electrodes arranged in an array; A pixel definition layer disposed on the active device array substrate, wherein the pixel definition layer has a plurality of openings arranged in an array, and each of the openings respectively exposes one of the pixel electrodes; A plurality of electroluminescent element layers are arranged in these openings, wherein each of the electroluminescent element layers is respectively arranged on one of the pixel electrodes; an electrode layer covering the pixel definition layer and the electroluminescence element layers; and A protective layer covers the electrode layer, and the protective layer includes: a buffer layer covering the pixel definition layer and the electroluminescent element layers; a first encapsulation film, which only partially covers the buffer layer, the first encapsulation film includes a plurality of island-shaped patterns separated from each other, and the island-shaped patterns are located above the pixel electrodes; and A second encapsulation film covers the buffer layer and the first encapsulation film. 2. The electroluminescent display panel according to claim 1, wherein the active element array substrate comprises a plurality of scanning lines, a plurality of data lines and a plurality of active elements, and the active elements are related to the scanning lines, the data The lines and the pixel electrodes are electrically connected correspondingly, and the scan lines, the data lines and the active elements are covered by the pixel definition layer. 3. The electroluminescence display panel according to claim 1, wherein the water vapor transmission rate of the first encapsulation film is greater than the water vapor transmission rate of the second encapsulation film. 4. The electroluminescence display panel according to claim 1, wherein the oxygen transmission rate of the first encapsulation film is greater than the oxygen transmission rate of the second encapsulation film. 5. The electroluminescent display panel according to claim 1, wherein the water vapor transmission rate of the first packaging film is between 0.1 g/m ² /day and 100 g/m ² /day, and The water vapor transmission rate of the second packaging film is between 1 g/m ² /day and 50 g/m ² /day. 6. The electroluminescent display panel according to claim 1, wherein the oxygen transmission rate of the first packaging film is between 0.1cc/m ² /day and 100c.c./m ² /day , and the oxygen transmission rate of the second packaging film is between 1c.c./m ² /day and 50c.c./m ² /day. 7. The electroluminescent display panel according to claim 1, wherein the material of the buffer layer and the second encapsulation film is an inorganic material, and the material of the first encapsulation film is an organic material, wherein each of the island-shaped The patterns are respectively located in one of the openings, wherein each electroluminescent element layer includes: A light-emitting layer configured between one of the pixel electrodes and the electrode layer, wherein the light-emitting layer includes an organic light-emitting layer or an inorganic light-emitting layer; a hole injection layer disposed between one of the pixel electrodes and the light-emitting layer; a hole transport layer configured between the hole injection layer and the light-emitting layer; and An electron injection layer is disposed between the light emitting layer and the electrode layer. 8. An electroluminescent display panel, characterized in that it comprises: An active element array substrate having a plurality of pixel electrodes arranged in an array; A pixel definition layer disposed on the active device array substrate, wherein the pixel definition layer has a plurality of openings arranged in an array, and each of the openings respectively exposes one of the pixel electrodes; A plurality of electroluminescent element layers are arranged in these openings, wherein each of the electroluminescent element layers is respectively arranged on one of the pixel electrodes; an electrode layer covering the pixel definition layer and the electroluminescence element layers; and A protective layer covers the electrode layer, and the protective layer includes: A first encapsulation film, the first encapsulation film includes a plurality of island-shaped patterns separated from each other, and these island-shaped patterns are generally located directly above the pixel electrodes and not located in areas other than directly above the pixel electrodes. 9. The electroluminescent display panel according to claim 8, wherein the active element array substrate comprises a plurality of scanning lines, a plurality of data lines and a plurality of active elements, and the active elements are related to the scanning lines, the data The lines and the pixel electrodes are electrically connected correspondingly, and the scan lines, the data lines and the active elements are covered by the pixel definition layer, wherein the water vapor transmission rate of the first encapsulation film is between 0.1g/m ² /day to 100g/m ² /day, wherein the oxygen transmission rate of the first packaging film is between 0.1cc/m ² /day to 100c.c./m ² /day, wherein the first packaging The material of the thin film is an organic material, wherein each of the island-shaped patterns is respectively located in one of the openings, wherein each of the electroluminescent element layers includes: A light-emitting layer configured between one of the pixel electrodes and the electrode layer, wherein the light-emitting layer includes an organic light-emitting layer or an inorganic light-emitting layer; a hole injection layer disposed between one of the pixel electrodes and the light-emitting layer; a hole transport layer configured between the hole injection layer and the light-emitting layer; and An electron injection layer is disposed between the light emitting layer and the electrode layer.

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