JP2021140885A - Display panel and manufacturing method thereof - Google Patents

Abstract

To prevent the occurrence of color mixing in a line bank type organic EL panel.SOLUTION: In an organic EL display panel in which a plurality of light emitting elements are arranged in a matrix via a flattening layer 12 on a substrate, each of the light emitting elements is defined by a partition wall 14 extending in the column direction and a pixel regulation layer 141 extending in the row direction and having a height lower than that of the partition wall 14, and a plurality of partition walls 14 are connected to each other at both ends in the column direction by a connecting portion 142, and in a plan view, a recessed portion 121 is present in the flattening layer 12 in an opening 14a between the partition walls 14 adjacent to each other in the row direction and adjacent to the connecting portion on at least one end side.SELECTED DRAWING: Figure 3

Description

The present invention relates to a display panel in which a plurality of organic electroluminescent elements (hereinafter referred to as "organic EL elements") are arranged in a matrix on a substrate, and a method for manufacturing the same.

In recent years, as a self-luminous display, an organic EL display panel in which a plurality of organic EL elements are arranged along a matrix direction on a substrate has been put into practical use as a display for electronic devices. Each organic EL element has a basic structure in which an organic light emitting layer containing an organic light emitting material is arranged between a pair of electrode pairs of an anode and a cathode, and a voltage is applied between the pair of electrode pairs during driving to obtain an anode. It is a current-driven light emitting element generated by recombination of holes injected into the organic light emitting layer from the above and electrons injected into the organic light emitting layer from the cathode.

In the past, each organic layer in an organic EL display panel was often formed by a dry process such as vacuum deposition, but with the progress of coating technology, especially printing equipment technology, in recent years, wet coating methods and the like have been used. Techniques for forming each organic layer by adopting a process are becoming widespread.

In the coating method, an ink obtained by dissolving a functional organic material in a solvent is applied to a necessary place by a printing device such as an inkjet device and then dried to form an organic layer, and a large organic EL display is used. Even if it is a panel, its equipment cost can be suppressed and the material utilization rate is high, which is excellent in terms of cost.

Recently, when an organic light emitting layer is formed by a coating method, a so-called line bank method is adopted in order to form the film thickness uniformly for each light emitting color (for example, Patent Document 1). In this line bank method, a plurality of partition walls (banks) extending in a row direction are arranged side by side on a substrate, and ink is continuously applied to an area partitioned by adjacent partition walls (hereinafter, simply referred to as "gap"). The plurality of sub-pixels arranged in the column direction are partitioned by a plurality of pixel regulation layers extending in the row direction.

Since the height of the pixel regulation layer is set lower than the partition wall and the liquid level of the applied ink, the ink can flow in the gap, and the film thickness of the organic layer in each light emitting element is achieved by leveling. Improves uniformity.

JP-A-2007-234232

However, when such a line bank method is adopted to form an organic light emitting layer by a coating method, there is a possibility that color mixing may occur particularly at the end portion in the column direction due to the method of manufacturing the partition wall. Do you get it.

The present disclosure has been made in view of the above problems, and even if an organic light emitting layer is formed by a coating method, the occurrence of color mixing at the end in the column direction is suppressed as much as possible to obtain good display image quality. It is an object of the present invention to provide a display panel that can be obtained and a method for manufacturing the same.

In the display panel according to one aspect of the present disclosure, a plurality of light emitting elements are arranged in a matrix via a flattening layer on a substrate, and the image display area and the periphery surrounding the image display area in a plan view are formed. A display panel having an area, a plurality of first partition walls extending in the column direction, and a plurality of second partition walls extending in the row direction and having a height from the substrate lower than that of the first partition wall. The plurality of light emitting elements are defined by the first partition wall and the second partition wall, and the plurality of first partition walls extend into the peripheral region and both ends in the column direction thereof. In a plan view, a recessed portion is formed in a portion of the flattening layer between the first partition walls adjacent in the row direction and adjacent to the connecting portion on at least one end side. Is characterized by the existence of.

Further, a plurality of methods for manufacturing a display panel according to another aspect of the present disclosure include a first step of preparing a substrate, a second step of forming a flattening layer on the substrate, and a plurality of methods at predetermined positions of the flattening layer. A third step of forming the recessed portion of the above, a fourth step of arranging a plurality of laminated bodies of a pixel electrode and a charge injection transport layer in a matrix on the flattening layer, and above the flattening layer and the laminated body. A fifth step of forming a second partition wall extending in the row direction between a plurality of electrodes adjacent in the column direction by a patterning process after forming a layer of the material of the second partition wall, and the flattening layer and the flattening layer. After forming a layer of the material of the first partition wall higher than the second partition wall on the laminated body, it is stretched in the column direction between a plurality of electrodes adjacent to each other in the row direction by a patterning process, and is in the column direction. A sixth step of forming a plurality of first partition walls in which both ends are connected by a connecting portion, and a seventh step of applying ink containing a light emitting material to the gaps between the plurality of partition walls to form a light emitting layer. Including, the sixth step includes a step of cleaning with a cleaning liquid at the time of the patterning process and a step of removing the cleaning liquid, and a predetermined position where a plurality of recessed portions are provided in the third step is described in a plan view. It is characterized in that it is in the gap between the plurality of first partition walls and at a position adjacent to the connecting portion of the first partition wall on at least one end side in the row direction.

According to the display panel and the manufacturing method thereof according to the above aspect, at least the organic light emitting layer is formed by the coating method to reduce the manufacturing cost, suppress the occurrence of color mixing as much as possible, and improve the display image quality. Can be done.

It is a block diagram which shows the whole structure of the organic EL display device which concerns on aspect of this disclosure. It is a schematic plan view which enlarged a part of the image display surface of the organic EL display panel in the said organic EL display device. (A) is a perspective view showing a partition wall end portion and its peripheral configuration in a peripheral region of the organic EL display panel being manufactured, and (b) is a plan view of a part of the organic EL display panel, (c). ) Is a schematic cross-sectional view taken along the line DD of (b). (A) to (d) are diagrams showing the steps from forming the partition wall to removing the rinsing liquid and applying the ink of the organic light emitting layers of R and G. (A) to (c) are diagrams for explaining the effect according to the aspect of the present disclosure. It is a schematic cross-sectional view along the line AA of FIG. It is a flowchart which shows the manufacturing process of an organic EL element. (A) to (e) are partial cross-sectional views schematically showing a manufacturing process of an organic EL element. (A) to (d) are partial cross-sectional views schematically showing the manufacturing process of the organic EL element following FIG. (A) and (b) are partial cross-sectional views schematically showing the manufacturing process of the organic EL element following FIG. (A) to (d) are partial cross-sectional views schematically showing the manufacturing process of the organic EL element following FIG. (A) to (d) are schematic cross-sectional views at the same positions as those in FIG. 3 (c) during the production of the organic EL display panel according to the modified example of the embodiment of the present disclosure. (A) is a plan view of a part of the organic EL display panel according to another modification during manufacturing, and (b) is a cross-sectional view taken along the line EE. (A) is a plan view of a part of the organic EL display panel according to still another modified example during manufacturing, and (b) is a cross-sectional view taken along the line FF. (A) is a plan view of a part of the organic EL display panel according to the background technology in the middle of manufacturing, (b) is a cross-sectional view taken along the line OH, and (c) is a partition wall end portion in a peripheral region. It is a perspective view which shows the shape of the vicinity. (A) to (d) are steps from forming a partition wall above the flattening resin layer in the organic EL display panel according to the background technology, washing with a cleaning liquid, drying, and applying ink containing an organic light emitting material. It is a figure which shows.

<< Background to one aspect of this disclosure >>
In the coating method, which is a kind of wet process, an ink obtained by dissolving an organic material having a predetermined function in a solvent is applied to a necessary place by a printing apparatus or the like, and then dried to form an organic layer. In particular, when the organic light emitting layer is formed by the coating method, a line bank method is adopted in which ink is continuously applied to the gaps between a plurality of partition walls extending in the row direction in order to form the film thickness uniformly for each emission color. In many cases.

FIG. 15A is a partial plan view of the organic EL display panel according to the background technique of the present invention during manufacturing (before forming a hole transport layer).

As shown in FIG. 15A, a plurality of partition walls 14 extend in parallel in one direction, and their terminal portions are connected by a connecting portion 142 to be closed. Further, the pixel regulation layers 141 are formed at regular intervals in the direction orthogonal to the extending direction of the partition wall 14, and one of them is formed by a region partitioned by a pair of adjacent partition walls 14 and a pair of pixel regulation layers 141. The range of sub-pixels is defined.

The organic EL display panel has a central image display area 50 and a peripheral area 60 (see FIG. 1) surrounding the image display area 50 in a plan view, and the peripheral area contributes to light emission. A dummy pixel region 61 in which an organic EL element (dummy light emitting element) is formed is included.

FIG. 15B shows a cross-sectional view taken along the line HH in the dummy pixel region 61 of FIG. 15A. As shown in the figure, a plurality of laminated bodies 25 formed by forming a flattening layer (interlayer insulating layer) 12 made of a resin material on a substrate (not shown) and superimposing a pixel electrode 13 and a hole injection layer 15 on the flattening layer (interlayer insulating layer) 12. Are arranged at regular pixel intervals, and a pixel regulation layer 141 is formed between them.

FIG. 15C is a perspective view showing the state around the end portion of the partition wall 14 of the organic EL display panel, and shows that the height of the pixel regulation layer 141 is lower than the height of the partition wall 14 in the line bank system. ing.

16 (a) to 16 (d) show the steps from the final step of the partition wall forming step of the organic EL display panel according to the background technology to the ink application of the organic light emitting layer.

FIG. 16A is a diagram showing a state in which the partition wall and the pixel regulation layer are patterned by using a photolithography method. At the final stage of the photolithography method, a step of washing away the developing solution and the like with a rinsing solution (cleaning solution: mainly pure water) is performed.

As shown in FIG. 16B, the rinse liquid remaining above the substrate moves the organic EL display panel in the C direction relative to the compressed air 501 discharged from the nozzle 500 of the air knife device (not shown). By letting the rinse liquid be brought to one end and blown off, it is removed.

Although the compressed air 501 is indicated by a linear arrow because it is shown in FIG. 16B for simplification, the compressed air 501 is actually a curtain-shaped compressed air extending in a direction parallel to the pixel regulation layer 141. It is discharged onto the substrate.

At this time, a pool of rinse liquid (hereinafter, referred to as “rinse liquid pool”) 401 that could not be completely removed by the wind pressure remains in the corner portion in front of the connecting portion 142 and in front of the pixel regulation layer 141. The remaining rinsing liquid evaporates by the baking treatment (baking treatment) executed thereafter, but the material of the hole injection layer 15 is slightly dissolved in the rinsing liquid, and residues of other members are left in the rinsing liquid. When the rinse liquid evaporates, the dissolved material components of the hole injection layer 15 are precipitated to become foreign matter 402, and the inner surface of the partition wall 14 is formed. Adhere to.

In particular, since the rinse liquid pool 401 in front of the connecting portion 142, which is higher than the pixel regulation layer 141, is large, the amount of foreign matter 402 that precipitates increases accordingly.

In this state, an ink containing an organic light emitting material is then applied to the gap. Since the partition 14 is made of a highly liquid-repellent resin material, the ink is usually maintained in a shape that rises above the upper edge of the partition 14 within the gap between the partition 14 due to its surface tension. However, if foreign matter adheres to the partition wall 14, the liquid repellency of that portion becomes low, the original raised shape cannot be maintained, and the partition wall 14 gets over the upper end portion of the partition wall 14 and is adjacent to the partition wall 14. Ink of different emission colors flows into the gaps where the inks are applied and the inks are mixed, and the portion does not emit light normally to the originally targeted color (hereinafter, in the present specification, the inks of different emission colors are mixed. , It may simply be "mixed".)

FIG. 16D is a schematic view showing how this color mixing occurs, and the applied ink generates a portion 310GR in which the green emitting color ink 310G and the adjacent red emitting color ink 310R are mixed. .. Since the line bank method is adopted, this color mixing gradually extends from the dummy pixel area 61 to the image display area 50, and the display image quality deteriorates.

Therefore, the inventor of the present application obtains good display image quality by suppressing the occurrence of color mixing of each emission color as much as possible even when the line bank method is adopted while reducing the cost by adopting the coating method. Therefore, as a result of diligent research, one aspect of the present disclosure has been reached.

<< Outline of one aspect of the present disclosure >>
In the display panel according to one aspect of the present disclosure, a plurality of light emitting elements are arranged in a matrix via a flattening layer on a substrate, and the image display area and the periphery surrounding the image display area in a plan view are formed. A display panel having an area, a plurality of first partition walls extending in the column direction, and a plurality of second partition walls extending in the row direction and having a height from the substrate lower than that of the first partition wall. The plurality of light emitting elements are defined by the first partition wall and the second partition wall, and the plurality of first partition walls extend into the peripheral region and both ends in the column direction thereof. In a plan view, a recessed portion is formed in a portion of the flattening layer between the first partition walls adjacent in the row direction and adjacent to the connecting portion on at least one end side. Exists.

According to this aspect, by adopting the line bank method and forming the organic light emitting layer by the coating method, it is possible to reduce the production cost and suppress the generation of color mixing caused by the precipitation of foreign substances as much as possible.

Further, in the display panel according to another aspect of the present disclosure, at least one dummy light emitting element is arranged in the peripheral region on the side where the recessed portion is present in each light emitting element row extending in the row direction. ..

Further, in the display panel according to another aspect of the present disclosure, a plurality of dummy light emitting elements are arranged in the peripheral region on the side where the recessed portion is present in each light emitting element row extending in the row direction. The second partition wall is not formed between at least a pair of dummy light emitting elements.

By not forming the second partition wall between at least a pair of dummy light emitting elements in this way, when removing the rinse liquid after patterning the partition wall at the manufacturing stage, the number of places where the rinse liquid pool exists is reduced and the color is mixed due to foreign matter. It becomes a display panel that does not occur.

Further, in the display panel according to another aspect of the present disclosure, a portion of the flattening layer corresponding to a gap between at least a pair of dummy light emitting elements on which the second partition wall is not formed is recessed.

Further, in the display panel according to another aspect of the present disclosure, groove portions extending in the column direction are continuously formed in the region of the flattening layer in which at least one dummy light emitting element is arranged.

According to this aspect, the total capacity of the recessed portion for accommodating the rinse liquid pool in the dummy pixel region of the peripheral region is increased, and even if foreign matter is deposited due to evaporation of the rinse liquid, the possibility of adhering to the inner wall of the first partition wall is further reduced. However, color mixing is less likely to occur.

Further, in the display panel according to another aspect of the present disclosure, a pixel electrode and a charge injection transport layer common to at least a pair of dummy light emitting elements in which the second partition wall is not interposed are arranged on the flattening layer. There is.

Here, when the pixel electrode is, for example, an anode, the charge injection transport layer is a functional layer having hole injection property and / or hole transport property.

Further, in the display panel according to another aspect of the present disclosure, the pixel electrode and the charge injection transport layer are not arranged in at least a pair of dummy light emitting elements in which the second partition wall is not interposed.

According to these aspects, when the rinse liquid is removed by wind pressure at the stage of manufacturing the partition wall, it is smoothly moved to the recessed portion provided at the position adjacent to the connecting portion and stored. , The rinse liquid pool remains, and the possibility that foreign matter adheres to the inner wall of the partition wall after drying can be reduced.

Further, the display panel according to another aspect of the present disclosure is formed on at least one dummy light emitting element arranged in the peripheral region on the side where the recessed portion is present in each light emitting element row extending in the row direction. Does not have a pixel electrode and a charge injection transport layer.

A method for manufacturing a display panel according to another aspect of the present disclosure includes a first step of preparing a substrate, a second step of forming a flattening layer on the substrate, and a plurality of recesses at predetermined positions of the flattening layer. The third step of forming the inlet portion, the fourth step of arranging a plurality of laminated bodies of the pixel electrodes and the charge injection transport layer in a matrix on the flattening layer, and above the flattening layer and the laminated body. After forming the material layer of the second partition wall, the fifth step of forming the second partition wall extending in the row direction between the plurality of electrodes adjacent in the column direction by the patterning process, the flattening layer and the lamination After forming a layer of the material of the first partition wall higher than the second partition wall above the body, it is stretched in the column direction between a plurality of electrodes adjacent to each other in the row direction by a patterning process, and both ends in the column direction. Includes a sixth step of forming a plurality of first partition walls connected by a connecting portion, and a seventh step of applying an ink containing a light emitting material to the gaps between the plurality of partition walls to form a light emitting layer. The sixth step includes a step of cleaning with a cleaning liquid at the time of the patterning process and a step of removing the cleaning liquid. It is a position within the gap of the first partition wall and adjacent to the connecting portion of the first partition wall on at least one end side in the row direction.

Further, in another aspect of the present disclosure, the step of removing the cleaning liquid in the sixth step includes a step of blowing the cleaning liquid toward one end in the row direction by wind pressure to remove the cleaning liquid, and the third step. In the plan view, the predetermined position where the plurality of recessed portions are provided is a position within the gap between the plurality of first partition walls and adjacent to the connecting portion of the partition walls on the side where the cleaning liquid is blown. ..

According to this aspect, it is possible to produce a display panel having excellent display image quality by forming an organic layer by a coating method to suppress the production cost and suppressing the generation of color mixing due to the adhesion of foreign substances to the partition wall.

In each of the above-described embodiments, "upper" does not mean an upward direction (vertically upward) in absolute spatial recognition, but is based on the stacking order in the laminated structure of each light emitting element arranged on the display panel. In addition, it is defined by the relative positional relationship. Specifically, in the light emitting element, the direction perpendicular to the main surface of the substrate and the direction from the substrate toward the laminate side is the upward direction. Further, for example, the expression "on the substrate" does not mean only the region directly in contact with the substrate, but also includes the region above the substrate via the laminate. Further, for example, when the expression "above the substrate" is used, it does not mean only the upper region separated from the substrate, but also includes the region on the substrate.

<< Embodiment >>
Hereinafter, the organic EL display panel and the manufacturing method thereof according to one aspect of the present disclosure will be described with reference to the drawings. It should be noted that each drawing includes a schematic one, and the scale and aspect ratio of each member may differ from the actual ones.

1. 1. Overall Configuration of Organic EL Display Device 1 FIG. 1 is a block diagram showing an overall configuration of the organic EL display device 1. The organic EL display device 1 is a display device used for, for example, a television, a personal computer, a mobile terminal, a business display, and the like.

The organic EL display device 1 includes an organic EL display panel 10 and a drive control unit 200 electrically connected to the organic EL display panel 10.

In the present embodiment, the organic EL display panel 10 is a top emission type display panel whose upper surface is a rectangular image display surface. The organic EL display panel 10 has an image display area 50 for displaying a central image and a peripheral area 60 surrounding the image display area 50 in a plan view, and is along the image display surface of the image display area 50. A plurality of organic EL elements (not shown) are arranged, and an image is displayed by combining the light emission of each organic EL element. The organic EL display panel 10 adopts an active matrix method as an example.

An organic EL element is also formed in a region close to the image display region 50 in the peripheral region 60, but this is a dummy organic EL element that does not emit light (hereinafter, organic that is arranged in the image display region 50 and emits light). The EL element is referred to as an "organic EL element" as it is, and the dummy organic EL element in the peripheral region 60 is referred to as a "dummy light emitting element" to distinguish between the two).

Generally, when the peripheral portion and the central portion of the substrate are compared, the ink dries faster in the peripheral portion, so that the film thickness of the organic layer in the central portion and the peripheral portion varies. Therefore, a dummy light emitting element that does not contribute to light emission is intentionally formed around the image display area 50 to make the film thickness of the organic layer of the organic EL element in the image display area 50 uniform.

The drive control unit 200 includes a drive circuit 210 connected to the organic EL display panel 10 and a control circuit 220 connected to an external device such as a computer or a receiving device such as a TV tuner. The drive circuit 210 is a power supply circuit that supplies electric power to each organic EL element in the image display area 50, a signal circuit that applies a voltage signal that controls the electric power supplied to each organic EL element, and a voltage signal at regular intervals. It has a scanning circuit that switches the application location.

The control circuit 220 controls the operation of the drive circuit 210 according to data including image information input from an external device or a receiving device.

In FIG. 1, four drive circuits 210 are arranged around the organic EL display panel 10 as an example, but the configuration of the drive control unit 200 is not limited to this, and the number of drive circuits 210 is not limited to this. And the position can be changed as appropriate. Further, for the sake of explanation below, as shown in FIG. 1, the direction along the long side of the upper surface of the organic EL display panel 10 is defined as the X direction, and the direction along the short side of the upper surface of the organic EL display panel 10 is defined as the Y direction. ..

2. Planar configuration of the organic EL display panel 10 FIG. 2 is a schematic plan view in which a part of the image display surface of the organic EL display panel 10 is enlarged. In the organic EL display panel 10, as an example, sub-pixels 100R, 100G, and 100B that emit light to R (red), G (green), and B (blue) (hereinafter, also simply referred to as R, G, and B) are arranged in a matrix. They are arranged in a shape. The sub-pixels 100R, 100G, and 100B are arranged alternately in the X direction, and a set of sub-pixels 100R, 100G, and 100B arranged in the X direction constitute one pixel P. In the pixel P, it is possible to express full color by combining the emission luminance of the sub-pixels 100R, 100G, and 100B whose gradation is controlled.

Further, in the Y direction, only one of the sub-pixel 100R, the sub-pixel 100G, and the sub-pixel 100B is lined up to form the sub-pixel row CR, the sub-pixel row CG, and the sub-pixel row CB, respectively. As a result, the pixels P of the organic EL display panel 10 as a whole are arranged in a matrix along the X and Y directions, and the image is displayed on the image display surface by combining the coloring of the pixels P arranged in the matrix. ..

Organic EL elements 2 (R), 2 (G), and 2 (B) (see FIG. 6) that emit light in the colors R, G, and B are arranged in the sub-pixels 100R, 100G, and 100B, respectively.

Further, the organic EL display panel 10 according to the present embodiment employs a so-called line bank method. That is, a plurality of partition walls (banks) 14 for partitioning the sub-pixel columns CR, CG, and CB for each column are arranged at intervals in the X direction (row direction), and the sub-pixel columns CR, CG, and CB have sub-pixels. 100R, 100G, and 100B share an organic light emitting layer.

However, in each of the sub-pixel sequences CR, CG, and CB, a plurality of pixel regulation layers 141 that insulate the sub-pixels 100R, 100G, and 100B from each other are arranged at intervals in the Y direction, and the sub-pixels 100R, 100G, and 100B are arranged. It can emit light independently.

The height of the pixel regulation layer 141 from the substrate is lower than the height of the liquid level when the organic light emitting layer is coated with ink, whereby the ink applied to the gap 14a between the adjacent partition walls 14 is in the Y direction (row). (Direction) fluidity is ensured, and leveling facilitates uniform formation of the thickness of the organic light emitting layer in the same light emitting color.

Each partition wall 14 extends in the Y direction, and its end portion extends into the peripheral region 60, and at the end portion, the partition wall 14 is connected by a connecting portion 142 having the same height as the partition wall 14, and is connected to a gap 14a between adjacent partition walls 14. The applied ink does not leak from the columnwise ends of the partition wall 14.

The connecting portions 142 are provided at both ends in the Y direction, whereby the gap 14a between the adjacent partition walls 14 can be regarded as an opening extending in a line in the Y direction. It will be described in other words as "opening 14a".

A recessed portion 121 is formed in a portion of the base layer (flattening layer 12) facing the opening 14a, which is the upper end portion in the Y direction and is adjacent to the connecting portion 142 in a plan view, as will be described later. .. The details of the structure around the terminal portion will be described later.

In FIG. 2, the partition wall 14 and the pixel regulation layer 141 are represented by dotted lines, but this is because the pixel regulation layer 141 and the partition wall 14 are not exposed on the surface of the image display surface and are on the image display surface. This is because it is located inside.

3. 3. The structure around the end portion of the partition wall FIG. 3A shows the periphery of one end portion in the row direction of the partition wall 14 in the peripheral region 60 of the organic EL display panel 10 in the process of being manufactured before the hole transport layer 16 is formed. 3 (b) is a perspective view showing the structure, FIG. 3 (b) is a plan view of a part of the organic EL display panel 10 which is also in the process of being manufactured, and FIG. 3 (c) is a line DD of FIG. 3 (b). It is a cross-sectional view taken along the line.

As shown in FIG. 3A, the terminal portions of the plurality of partition walls 14 are connected by the connecting portion 142, and the laminate 25 of the pixel electrode 13 for the dummy light emitting element and the hole injection layer 15 (FIG. 3C). (See) are formed on the flattening layer 12 at regular intervals.

In the present embodiment, as shown in FIG. 3B, the pixel regulation layer 141 for partitioning the dummy light emitting element formed in the dummy pixel region 61 outside the image display region 50 is not formed, so that they are adjacent to each other. A gap 125 is generated between the laminated bodies 25.

Since it is not necessary for the dummy light emitting element to actually supply a current to emit light, there is no particular problem even if the pixel regulation layer 141 for electrically insulating them is not formed.

A recessed portion 121 having a predetermined capacity is formed in a portion facing the opening 14a of the flattening layer 12 and adjacent to the connecting portion 142 in a plan view.

4 (a) to 4 (d) are perspective views showing a process from the final stage of the process of forming the partition wall 14 of the organic EL display panel 10 according to the present embodiment to the application of ink to the organic light emitting layer. a) to (c) are schematic cross-sectional views for explaining the effect in this embodiment.

FIG. 4A is a diagram showing a state immediately after patterning the partition wall 14 by using a photolithography method, and at the final stage, a step of washing away the developing solution and the like with a rinsing solution (cleaning solution) is performed.

As shown in FIG. 4B, the rinse liquid remaining on the substrate moves the organic EL display panel in the C direction relative to the compressed air 501 discharged from the nozzle 500 of the air knife device (not shown). By letting it blow off from one end of the substrate, it is removed.

At this time, since the pixel regulation layer 141 is not formed in the dummy pixel region 61, the rinse liquid pool 401 does not occur in the middle and is quickly blown up to the vicinity of the connecting portion 142, and most of them are outside the organic EL display panel 10. However, at the position in front of the connecting portion 142, the connecting portion 142 acts as a barrier, and the rinse liquid pool 401 inevitably remains (see FIGS. 5A and 5B).

After that, the intermediate product of the organic EL display panel 10 is heated at a predetermined temperature to perform the baking process. As shown in FIG. 5 (b), the connecting portion of the upper surface (the surface facing the opening 14a) of the flattening layer 12 is connected. A recessed portion 121 is provided at a position in front of 142, and the pixel regulation layer 141 is not formed above this portion. Therefore, even if the rinse liquid in the rinse liquid pool 401 evaporates due to the baking process, foreign matter is formed. 402 is deposited in the recessed portion 121 and does not adhere to the inner wall of the partition wall 14 (see FIGS. 4 (c) and 5 (c)).

Therefore, it is possible to prevent color mixing from occurring even if the inks of the respective emission colors are applied to the opening 14a in the subsequent step (see FIG. 4D. In the figure, the ink 310G whose emission color is green, And the coating state of only the ink 310R whose emission color is red is shown as an example).

In the present embodiment, the pixel regulation layer 141 is not formed between all the dummy light emitting elements in the dummy pixel region 61, but the height of the partition wall 14 and the connecting portion 142 is usually about 1 μm. The height of the pixel restricting layer 141 is at most about 0.5 μm, and even if the pixel restricting layer 141 is present in the dummy pixel region 61, the rinse liquid pool 401 generated in front of the pixel restricting layer 141 is generated. Is not so large, and depending on the material of the hole injection layer 15 and the type of rinsing liquid used, foreign matter may not dissolve so much in the rinsing liquid, and even if it precipitates before the pixel regulation layer 141, the color may be mixed. It may not be possible to provoke it.

In that case, there is no particular problem even if the pixel regulation layer 141 is formed in the dummy pixel area 61, and even if the pixel regulation layer 141 in the dummy pixel area 61 is removed, at least a pair near the end portion. In some cases, only the pixel control layer 141 between the dummy light emitting elements is sufficient.

The capacity of the recess 121 may, for example, if 600μm ³ ~240000μm ³ degrees, and more specifically, ease of dissolution in the rinse solution of the material of the hole injection layer 15 and the rinsing liquid are formed The size of the reservoir 401, the width of the opening 14a, the length, and the like can be taken into consideration in advance by experiments and the like, and the depth of the recessed portion 121 and the like are determined accordingly.

Further, in the manufacturing process, it is not necessary to provide a recessed portion 121 at the terminal portion of the partition wall 14 on the side where the rinse liquid is not blown.

4. Laminated structure and manufacturing method of the organic EL display panel 10 Hereinafter, the laminated structure and manufacturing method of the organic EL display panel 10 will be described with reference to the drawings.

(A) Laminated Structure of Organic EL Display Panel 10 FIG. 6 is a schematic cross-sectional view of the organic EL display panel 10 at a portion along the line AA in the image display area 50 of FIG.

In the organic EL display panel 10, one pixel is composed of three sub-pixels that emit light of R, G, and B, and each sub-pixel emits the corresponding color of the organic EL elements 2 (R) and 2 (G). ), 2 (B).

Since the organic EL elements 2 (R), 2 (G), and 2 (B) of each emission color basically have substantially the same configuration, they will be described as the organic EL element 2 when they are not distinguished.

As shown in FIG. 6, the organic EL element 2 includes a substrate 11, a flattening layer 12, a pixel electrode (anode) 13, a partition wall 14, a hole injection layer 15, a hole transport layer 16, an organic light emitting layer 17, and electron transport. It is composed of a layer 18, an electron injection layer 19, a counter electrode (cathode) 20, and a sealing layer 21.

The substrate 11, the flattening layer 12, the electron transport layer 18, the electron injection layer 19, the counter electrode 20, and the sealing layer 21 are not formed for each pixel, but are provided in a plurality of organic EL display panels 10. It is commonly formed in the organic EL element 2.

(1) Substrate The substrate 11 includes a base material 111 which is an insulating material and a TFT (Thin Film Transistor) layer 112. A drive circuit is formed in the TFT layer 112 for each sub-pixel. The base material 111 includes, for example, a glass substrate, a quartz substrate, a silicon substrate, a molybdenum sulfide, copper, zinc, aluminum, stainless steel, a metal substrate such as magnesium, iron, nickel, gold, and silver, a semiconductor substrate such as gallium arsenic, and a plastic substrate. Etc. can be adopted.

As the plastic material, either a thermoplastic resin or a thermosetting resin may be used. For example, polyethylene, polypropylene, polyamide, polyimide (PI), polycarbonate, acrylic resin, polyethylene terephthalate (PET), polybutylene terephthalate, polyacetal, other fluororesins, styrene-based, polyolefin-based, polyvinyl chloride-based, polyurethane-based, Various thermoplastic elastomers such as fluororubber type and chlorinated polyethylene type, epoxy resin, unsaturated polyester, silicone resin, polyurethane, etc., or copolymers, blends, polymer alloys, etc. mainly composed of these can be mentioned. A laminated body in which one type or two or more types are laminated can be used.

(2) Flattening layer The flattening layer 12 is formed on the substrate 11. The flattening layer 12 is made of a resin material and is for flattening a step on the upper surface of the TFT layer 112. Examples of the resin material include a positive type photosensitive material. Moreover, as such a photosensitive material, an acrylic resin, a polyimide resin, a siloxane resin, and a phenol resin can be mentioned. Further, although not shown in the cross-sectional view of FIG. 6, contact holes are formed in the flattening layer 12 for each sub-pixel.

(3) Pixel Electrode The pixel electrode 13 includes a metal layer made of a light-reflecting metal material and is formed on the flattening layer 12. The pixel electrode 13 is provided for each sub-pixel and is electrically connected to the TFT layer 112 through a contact hole (not shown).

In this embodiment, the pixel electrode 13 functions as an anode.

Specific examples of the metal material having light reflectivity include Ag (silver), Al (aluminum), aluminum alloy, Mo (molybdenum), APC (alloy of silver, palladium and copper), ARA (silver, rubidium, gold). , MoCr (alloy of molybdenum and chromium), MoW (alloy of molybdenum and tungsten), NiCr (alloy of nickel and chromium) and the like.

The pixel electrode 13 may be composed of a metal layer alone, but as a laminated structure in which a layer made of a metal oxide such as ITO (indium tin oxide) or IZO (indium tin oxide) is laminated on the metal layer. May be good.

(4) Hole Injection Layer The hole injection layer 15 is provided on the pixel electrode 13 for the purpose of promoting the injection of holes from the pixel electrode 13 into the organic light emitting layer 17. For the hole injection layer 15, for example, oxides such as Ag (silver), Mo (molybdenum), Cr (chromium), V (vanadium), W (tungsten), Ni (nickel), and Ir (iridium) are used. , In this embodiment, a tungsten oxide (WOx) is used.

(5) Partition / Pixel Restriction Layer The partition 14 partitions a plurality of pixel electrodes 13 arranged for each sub-pixel above the substrate 11 for each row, and the sub-pixel rows CR and CG arranged in the X direction. , CB has a line bank shape extending in the Y direction.

A material having electrical insulation is used for the partition wall 14. As a specific example of the electrically insulating material, for example, an insulating organic material (for example, acrylic resin, polyimide resin, novolak resin, phenol resin, etc.) is used.

The partition wall 14 functions as a structure for preventing the applied inks of each color from overflowing and mixing when the organic light emitting layer 17 is formed by the coating method.

When a resin material is used, it is preferable to have photosensitivity from the viewpoint of processability. The photosensitivity may be either positive type or negative type.

The partition wall 14 preferably has resistance to an organic solvent and heat. Further, in order to suppress the outflow of ink, the partition wall 14 is formed of a material having liquid repellency, or the surface is imparted with liquid repellency by surface treatment.

The pixel regulation layer 141 is made of an electrically insulating material, and partitions pixel electrodes 13 adjacent to each other in the Y direction (FIG. 2) in each sub-pixel row.

As described above, the height of the pixel regulation layer 141 from the substrate 11 is lower than the height of the partition wall 14 and the liquid level of the ink containing the organic light emitting material applied to the opening 14a. Further, the pixel regulation layer 141 improves the electrical insulation between the pixel electrodes 13 adjacent to each other in the Y direction.

Specific examples of the electrically insulating material used for the pixel regulation layer 141 include a resin material and an inorganic material exemplified as the material of the partition wall 14.

(6) Hole Transport Layer The hole transport layer 16 has a function of transporting holes injected from the hole injection layer 15 to the organic light emitting layer 17. The hole transport layer 16 is formed of, for example, polyfluorene or a derivative thereof, or a polymer compound such as polyarylamine or a derivative thereof.

(7) Organic Light Emitting Layer The organic light emitting layer 17 is formed in the opening 14a and has a function of emitting light of each color of R, G, and B by recombination of holes and electrons. In particular, when it is necessary to specify and explain the emission color, the organic light emitting layers 17 (R), 17 (G), and 17 (B) are described.

Examples of the material of the organic light emitting layer 17 include an oxinoid compound, a perylene compound, a coumarin compound, an azacmarin compound, an oxazole compound, an oxadiazole compound, a perinone compound, a pyrolopyrrole compound, a naphthalene compound, an anthracene compound, a fluorene compound, and a fluorantene compound. Tetracene compound, pyrene compound, coronen compound, quinolone compound and azaquinolone compound, pyrazoline derivative and pyrazolone derivative, rhodamine compound, chrysene compound, phenanthrene compound, cyclopentadiene compound, stilben compound, diphenylquinone compound, styryl compound, butadiene compound, dicyanomethylenepyrane Compounds, dicyanomethylenethiopyran compounds, fluorescein compounds, pyrylium compounds, thiapyrylium compounds, selenapyrylium compounds, tellropyrylium compounds, aromatic aldaziene compounds, oligophenylene compounds, thioxanthene compounds, cyanine compounds, acrydin compounds, 8-hydroxyquinoline compounds It is preferably formed of a fluorescent substance such as a metal complex, a metal complex of a 2-bipyridine compound, a complex of a shift salt and a group III metal, an oxine metal complex, or a rare earth complex.

(8) Electron transport layer The electron transport layer 18 has a function of transporting electrons from the counter electrode 20 to the organic light emitting layer 17. The electron transport layer 18 is made of an organic material having high electron transportability.

Examples of the organic material used for the electron transport layer 18 include π-electron low-molecular-weight organic materials such as an oxadiazole derivative (OXD), a triazole derivative (TAZ), and a phenanthroline derivative (BCP, Bphen).

(9) Electron injection layer The electron injection layer 19 has a function of injecting electrons supplied from the counter electrode 20 into the organic light emitting layer 17. The electron injection layer 19 is formed by, for example, doping an organic material having high electron transportability with a dope metal selected from an alkali metal, an alkaline earth metal, or a rare earth element.

The metals corresponding to alkali metals are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr), and the metals corresponding to alkaline earth metals are Calcium (Ca), Strontium (Sr), Barium (Ba), Rubidium (Ra). In addition, as a rare earth element, for example,
Eribium (Er), thulium (Tm), ytterbium (Yb) and the like.

Examples of the organic material used for the electron injection layer 19 include π-electron low-molecular-weight organic materials such as an oxadiazole derivative (OXD), a triazole derivative (TAZ), and a phenanthroline derivative (BCP, Bphen). Be done.

(10) Counter electrode The counter electrode 20 is made of a translucent conductive material and is formed on the electron injection layer 19. The counter electrode 20 functions as a cathode.

As the counter electrode 20, for example, a metal thin film or a transparent conductive film such as ITO or IZO can be used. As the material of the metal thin film, it is desirable to form a metal thin film made of at least one of aluminum, magnesium, silver, aluminum-lithium alloy, magnesium-silver alloy and the like.

(11) Sealing layer The sealing layer 21 prevents organic layers such as the internal hole transport layer 16, the organic light emitting layer 17, and the electron injection layer 19 from being exposed to external moisture and air and deteriorating. It is provided to do so.

The sealing layer 21 is formed by using a translucent material such as silicon nitride (SiN) or silicon oxynitride (SiON).

(12) Others Although not shown in FIG. 6, a polarizing plate for antiglare or an upper substrate may be attached onto the sealing layer 21 via a transparent adhesive. Further, a color filter for correcting the chromaticity of the light emitted by each organic EL element 2 may be attached. As a result, the hole transport layer 16, the organic light emitting layer 17, the electron injection layer 19, and the like can be further protected from external moisture, air, and the like.

(B) Manufacturing Method of Organic EL Display Panel 10 Hereinafter, a manufacturing method of the organic EL display panel 10 will be described.

7A and 7B are flowcharts showing a manufacturing process of the organic EL display panel 10, FIGS. 8A to 8F, FIGS. 9A to 9D, 10A and 10B, and 11B. (A) to (d) are schematic cross-sectional views showing the state in each step in the manufacture of the organic EL display panel 10.

(1) Substrate Preparation Step First, as shown in FIG. 8A, a TFT layer 112 is formed on the substrate 111 to prepare the substrate 11 (step S1 in FIG. 7). The TFT layer 112 can be formed by a known method for manufacturing a TFT.

(2) Flattening layer forming step Next, as shown in FIG. 8B, the flattening layer 12 is formed on the substrate 11 (step S2 in FIG. 7).

Specifically, a resin material having a constant fluidity is applied, for example, by a die coating method so as to fill the unevenness on the substrate 11 by the TFT layer 112 along the upper surface of the substrate 11. As a result, the upper surface of the flattening layer 12 has a flattened shape along the upper surface of the base material 111.

Further, a contact hole (not shown) is formed in the flattening layer 12 at a position on the source electrode of the TFT element, for example, by a photolithography method. The contact hole is formed by patterning or the like so that the surface of the source electrode is exposed at the bottom thereof. Along with the formation of the contact hole, the recessed portion 121 (see FIGS. 3 (a) and 3 (c)) at a position to be adjacent to the connecting portion 142 of the opening 14a was also formed in the same photolithography process. If they are formed at the same time, the manufacturing process can be simplified.

Next, a connection electrode layer is formed along the inner wall of the contact hole. A part of the upper part of the connecting electrode layer is arranged on the flattening layer 12. For the formation of the connection electrode layer, for example, a sputtering method can be used, and after forming a metal film, patterning may be performed using a photolithography method and a wet etching method.

(3) Step of Forming Pixel Electrode / Hole Injection Layer Next, as shown in FIG. 8 (c), the pixel electrode material layer 130 is formed on the flattening layer 12. The pixel electrode material layer 130 can be formed by, for example, a vacuum vapor deposition method, a sputtering method, or the like.

Further, the hole injection material layer 150 is formed on the pixel electrode material layer 130 (FIG. 8 (d)). The hole injection material layer 150 can be formed by, for example, a reactive sputtering method or the like.

Then, as shown in FIG. 8E, the pixel electrode material layer 130 and the hole injection material layer 150 are simultaneously patterned by etching, and a plurality of pixel electrodes 13 and hole injection layers partitioned for each sub-pixel are formed. A laminated body 25 composed of 15 is formed (step S3 in FIG. 7).

The method of forming the pixel electrode 13 and the hole injection layer 15 is not limited to the above method. For example, the pixel electrode material layer 130 is first patterned to form the pixel electrode 13, and then the hole injection layer 15 is formed. It may be formed.

(4) Partition / Pixel Restriction Layer Forming Step Next, the partition 14 and the pixel regulation layer 141 are formed (step S4 in FIG. 7).

In the present embodiment, the pixel regulation layer 141 and the partition wall 14 are formed in separate steps.

(4-1) Pixel Restriction Layer Forming Step First, in order to partition the pixel electrode array in the Y direction (FIG. 2) for each sub-pixel, a pixel regulation layer 141 extending in the X direction is formed.

As shown in FIG. 9A, a photosensitive resin material used as a material for the pixel regulation layer 141 is uniformly applied onto the flattening layer 12 on which the pixel electrode 13 and the hole injection layer 15 are formed. After the baking process, the pixel regulation layer material layer 1410 having a thickness necessary for obtaining the target height of the pixel regulation layer 141 is formed.

As a specific coating method, for example, a wet process such as a die coating method, a slit coating method, or a spin coating method can be used. After coating, for example, vacuum drying and low-temperature heat drying (pre-baking) at about 60 ° C. to 120 ° C. are performed to remove unnecessary solvents, and the pixel-regulating layer material layer 1410 is fixed to the flattening layer 12. preferable.

Then, the pixel regulation layer material layer 1410 is patterned by using a photolithography method.

For example, when the pixel regulation layer material layer 1410 has positive photosensitivity, the portion to be left as the pixel regulation layer 141 is shielded from light, and the portion to be removed is a transparent photomask (not shown) of the pixel regulation layer material layer. 1410 is exposed.

Next, the pixel regulation layer 141 can be formed by developing and removing the exposed region of the pixel regulation layer material layer 1410. As a specific developing method, for example, the entire substrate 11 is immersed in a developing solution such as an organic solvent or an alkaline solution that dissolves a portion exposed to exposure to the pixel regulation layer material layer 1410, and then a rinsing solution such as pure water is used. The substrate 11 may be washed with.

The rinse liquid remaining on the substrate is the rinse liquid along the row direction due to the wind pressure of the compressed air 501 discharged from the nozzle 500 of the air knife device, as described in FIG. 4 (b) above. Remove by skipping from one end.

In the case of the pixel regulation layer 141, since it is not connected at the end of the gap between the adjacent pixel regulation layers 141, the rinse liquid pool 401 is hardly generated at this stage.

Then, by baking (post-baking) at a predetermined temperature, a pixel regulation layer 141 extending in the X direction can be formed on the flattening layer 12 (FIG. 9 (b)).

The pixel regulation layer 141 is not formed between the dummy light emitting elements in the dummy pixel region 61 (see FIGS. 3 (b) and 3 (c)).

(4-2) Partition Form Forming Step Next, the partition wall 14 extending in the Y direction is formed in the same manner as the pixel regulation layer 141.

That is, a resin material for partition walls is applied onto the flattening layer 12 on which the pixel electrode 13, the hole injection layer 15, and the pixel regulation layer 141 are formed by using a die coating method or the like, and the target is after the baking treatment. A partition wall material layer 140 having a thickness required to obtain the height of the partition wall 14 is formed (FIG. 9 (c)), and the partition wall 14 extending in the Y direction is patterned on the partition wall material layer 140 by a photolithography method.

At this time, the rinse liquid remaining on the substrate is expelled along the row direction by an air knife device, and is removed by being blown off from one end in the row direction (FIG. 4 (b)). Since the gap (opening 14a) between the adjacent partition walls 14 is closed by the connecting portion 142 at the end in the row direction, the rinse liquid pool 401 can be formed above the recessed portion 121 in front of the connecting portion 142 (FIG. 4 (FIG. 4). c), see FIG. 5 (b)).

Then, the partition wall 14 is formed by baking at a predetermined temperature (FIG. 9 (d)). At this time, even if the rinse liquid in the rinse liquid pool 401 evaporates and foreign matter is deposited, it remains in the recessed portion 121, so that it does not adhere to the inner wall of the partition wall 14 and color mixing does not occur.

In the above, the material layers of the pixel regulation layer 141 and the partition wall 14 are formed by a wet process and then patterned, but one or both of the material layers are formed by a dry process and a photolithography method is performed. Therefore, patterning may be performed.

(5) Hole Transport Layer Forming Step Next, as shown in FIG. 10 (a), an ink containing the constituent material of the hole transport layer 16 is applied to the opening 14a defined by the partition wall 14 in a printing apparatus. It is discharged from the nozzle 3011 of the head 301 and applied onto the hole injection layer 15 in the opening 14a. At this time, the ink of the hole transport layer 16 is applied so as to extend along the Y direction (FIG. 2) above the pixel electrode row. Then, it is dried to form the hole transport layer 16 (step S5 in FIG. 7).

(6) Organic light emitting layer forming step Next, the organic light emitting layer 17 is formed above the hole transport layer 16 (step S6 in FIG. 7).

Specifically, as shown in FIG. 10B, ink containing a luminescent material having a luminescent color corresponding to each opening 14a is sequentially ejected from the nozzle 3011 of the coating head 301 of the printing apparatus into the opening 14a. Is applied on the hole transport layer 16. At this time, the ink is applied so as to be continuous even above the pixel regulation layer 141. As a result, the ink can flow along the Y direction, the uneven coating of the ink can be reduced, and the film thickness of the organic light emitting layer 17 in the same sub-pixel row can be made uniform.

Then, the substrate 11 after the ink is applied is carried into the vacuum drying chamber and heated in a vacuum environment to evaporate the organic solvent in the ink. As a result, the organic light emitting layer 17 can be formed.

(7) Electron Transport Layer Forming Step Next, as shown in FIG. 11A, the electron transport layer 18 is formed on the organic light emitting layer 17 and the partition wall 14 (step S7 in FIG. 7). The electron transport layer 18 is formed, for example, by forming an electron transportable organic material in common with each sub-pixel by a vapor deposition method, but it may be formed by a wet process.

(8) Electron Injection Layer Forming Step Next, as shown in FIG. 11B, an electron injection layer 19 is formed on the electron transport layer 18 (step S8 in FIG. 7). The electron injection layer 19 is formed, for example, by forming an electron-transporting organic material and a dope metal in common on each sub-pixel by a co-evaporation method.

(9) Counter electrode forming step Next, as shown in FIG. 11 (c), the counter electrode 20 is formed on the electron injection layer 19 (step S9 in FIG. 7). The counter electrode 20 is formed by forming a film of ITO, IZO, silver, aluminum or the like by a sputtering method or a vacuum vapor deposition method.

(10) Sealing layer forming step Next, as shown in FIG. 11D, the sealing layer 21 is formed on the counter electrode 20 (step S10 in FIG. 7). The sealing layer 21 can be formed by forming a film of SiON, SiN, or the like by a sputtering method, a CVD method, or the like.

As a result, the organic EL display panel 10 is completed.

The above manufacturing method is merely an example and can be changed as appropriate.

≪Modification example≫
Although embodiments such as an organic EL display panel and a method for manufacturing an organic EL display panel have been described above as one aspect of the present invention, the present invention is based on the above embodiments except for its essential characteristic components. There are no restrictions. Hereinafter, other aspects (modifications) of the present invention will be described.

(1) In the above embodiment, the recessed portion 121 for depositing foreign matter is formed at a position in front of the connecting portion 142 of the opening 14a, but as shown in the schematic cross-sectional view of FIG. 12A, the recessed portion 121 is formed. In addition, the recessed portion 122 may be provided in a portion where the pixel restricting layer 141 is not formed between the laminated bodies 25 of the dummy light emitting elements. It is understood that this increases the total capacity of the recessed portion where the foreign matter can be deposited, and further suppresses the adhesion of the foreign matter to the inner wall surface of the partition wall 14.

Further, as shown in FIG. 12 (b), in the modified example of FIG. 12 (a), the laminated body 25 of the dummy light emitting elements may not be formed. This is because the laminated body 25 does not have to have an indispensable configuration because the dummy light emitting element does not need to emit light.

Further, as shown in FIG. 12 (c), the laminated body 25 of the dummy light emitting elements may not be formed in FIG. 3 (c). As a result, the rinse liquid can be smoothly moved in the dummy pixel region 61 up to the recessed portion 121 due to the wind pressure of the air knife device, and the rinse liquid pool 401 in this range is less likely to occur.

This modification can be applied even when there is only one dummy light emitting element in the column direction in the dummy pixel region 61, and a plurality of dummy light emitting elements are arranged in the column direction, and a part or all of them are arranged. It can be applied even if the pixel regulation layer 141 is formed between the two.

Further, as shown in FIG. 12D, a plurality of dummy light emitting element pixels may be continuously laminated with the pixel electrode 131 and the hole injection layer 151 in the dummy pixel region 61.

Also in this case, the rinse liquid can be smoothly removed in the dummy pixel region 61 up to the recessed portion 121. In the modified examples of FIGS. 12 (a) and 12 (b) above, not all of the laminated bodies 25 are necessarily removed. The recessed portion 122 may not be formed at a position corresponding to the gap 125, and in that case, it is considered desirable that the recessed portion 122 is formed in at least one gap 125 portion closest to the connecting portion 142.

Further, in the modified example of FIG. 12C, the upper surface of the flattening layer 12 excluding the recessed portion 121 does not necessarily have to be flat in the entire range of the dummy pixel region 61 of each sub-pixel row, for example, at least a dummy. If it is flat in a range wider than the area occupied by one light emitting element, it is considered that it contributes to the smooth removal of the rinse liquid to some extent.

Similarly, the range extending in the column direction of the laminated body 25 (pixel electrode 131 and hole injection layer 151) in the modified example of FIG. 12D does not necessarily have to cover the entire range of the dummy pixel region 61.

(2) Further, as another modification, a groove portion extending in the Y direction (row direction) may be formed in the flattening layer 12 separately from the recessed portion 121.

FIG. 13A is a schematic plan view of a part including the dummy pixel region 61 of the organic EL display panel 10 before the formation of the organic light emitting layer 17 in the modified example in this case, and FIG. 13B is FIG. 13 (b). It is a cross-sectional view taken along the line EE of a).

As shown in both figures, the dummy pixel region 61 of the flattening layer 12 may be provided with a groove portion 123 extending in the Y direction without forming the laminated body 25. It is desirable that the groove portion 123 is connected to the recessed portion 121, but even if the groove portion 123 is not connected, even if a rinse liquid pool 401 occurs on the way to the recessed portion 121 in the dummy pixel region 61, the groove portion 123 is inside the groove portion 123. It becomes possible to deposit foreign matter, and there is no possibility that foreign matter adheres to the inner wall of the partition wall 14.

14 (a) is a schematic plan view of a part including the dummy pixel region 61 of the organic EL display panel 10 before the formation of the organic light emitting layer 17 in still another modified example, and FIG. 14 (b) is a schematic plan view of a part including the dummy pixel region 61. It is a cross-sectional view taken along the line FF of (a).

As shown in both figures, a laminated body 25 extending continuously in the Y direction may be formed above the groove portion 123 in FIGS. 13A and 13B. Even in this case, since the groove 124 is formed on the hole injection layer 151, the same effect as in the case of FIG. 13 can be obtained.

The length of the groove portions 123 and 124 in the row direction does not necessarily extend to the entire width of the dummy pixel region 61 in the Y direction, and for example, a row including an arrangement region of 1 to 3 dummy light emitting elements in the row direction. It may be a directional length.

(3) In the above embodiment, the recessed portion 121 is formed only at one end in the row direction (the end in the direction in which the rinse liquid is attracted by wind pressure during manufacturing), but for example, the central portion of the substrate is rotated. When the rinse liquid is blown off and removed by centrifugal force on the shaft, a recessed portion 121 is also formed at the other end portion.

(4) In the laminated structure of the organic EL element of the above embodiment, it is not always necessary to include all of the functional layers of the hole injection layer 15, the hole transport layer 16, the electron transport layer 18, and the electron injection layer 19. For example, the electron transport layer 18 and the electron injection layer 19 may be abolished to form the electron injection transport layer.

(5) In the organic EL display panel 10 according to the above embodiment, as shown in FIG. 2, the stretching direction of the pixel regulation layer 141 is the long axis X direction of the organic EL display panel 10, and the stretching direction of the partition wall 14 is the organic EL display. Although it was in the Y direction on the minor axis of the panel 10, the stretching directions of the pixel regulation layer 141 and the partition wall 14 may be opposite. Further, the stretching direction of the pixel insulating layer and the partition wall may be a direction irrelevant to the shape of the organic EL display panel 10.

Further, in the organic EL display panel 10 according to the above embodiment, the image display surface is rectangular as an example, but the shape of the image display surface is not limited and can be changed as appropriate.

(6) Further, the organic EL display panel 10 according to the above embodiment adopts an active matrix method, but the present invention is not limited to this, and a passive matrix method may be adopted. Further, it can be applied not only to the top emission type organic EL display panel but also to the bottle emission type organic EL display panel.

≪Supplement≫
The organic EL element and its manufacturing method, the organic EL display panel, the organic EL display device, and the electronic device according to the present disclosure have been described above based on the embodiments and modifications, but the present invention describes the above embodiments and modifications. It is not limited to the example. It is realized by arbitrarily combining the components and functions in the embodiment and the modification without departing from the spirit of the present invention and the embodiment obtained by applying various modifications that a person skilled in the art can think of. Also included in the present invention.

The organic EL display panel according to the present disclosure can be widely used as a display panel used in various electronic devices.

1 Organic EL display device 2 Organic EL display device 10 Organic EL display panel 11 Substrate 12 Flattening layer 13 Pixel electrode 14 Partition 14a Opening 15 Hole injection layer 16 Hole transport layer 17 Organic light emitting layer 18 Electron transport layer 19 Electron injection layer 20 Counter electrode 21 Sealing layer 25 Laminated body 50 Image display area 60 Peripheral area 61 Dummy pixel area 100B, 100G, 100R Sub-pixels 121, 122 Recessed parts 123, 124 Grooves 140 Partition material layer 141 Pixel regulation layer 142 Connecting parts 401 Rinse liquid Drop 402 Foreign matter

Claims (10)

A display panel in which a plurality of light emitting elements are arranged in a matrix via a flattening layer on a substrate, and has an image display area and a peripheral area surrounding the image display area in a plan view.
Multiple first bulkheads extending in the row direction,
A plurality of second partition walls extending in the row direction and having a height from the substrate lower than that of the first partition wall.
With
The plurality of light emitting elements are defined by the first partition wall and the second partition wall.
The plurality of first partition walls extend into the peripheral region and are connected by connecting portions at both ends in the column direction.
In a plan view, the flattening layer is characterized in that a recess is present in a portion of the flattening layer between the first partition walls adjacent to each other in the row direction and adjacent to the connecting portion on at least one end side. Display panel. The display panel according to claim 1, wherein at least one dummy light emitting element is arranged in the peripheral region on the side of each light emitting element row extending in the row direction where the recessed portion exists. A plurality of dummy light emitting elements are arranged in the peripheral region on the side of each light emitting element row extending in the row direction where the recessed portion exists, and the second dummy light emitting element is located between at least a pair of dummy light emitting elements. The display panel according to claim 2, wherein no partition wall is formed. The display panel according to claim 3, wherein a portion of the flattening layer corresponding to a gap between at least a pair of dummy light emitting elements on which the second partition wall is not formed is recessed. The display panel according to claim 2 or 3, wherein a groove extending in a row direction is continuously formed in a region of the flattening layer in which at least one dummy light emitting element is arranged. The display panel according to claim 3, wherein a pixel electrode common to at least a pair of dummy light emitting elements and a charge injection transport layer are arranged on the flattening layer without the second partition wall interposed therebetween. .. The display panel according to claim 3 or 4, wherein the pixel electrode and the charge injection transport layer are not arranged in at least a pair of dummy light emitting elements having no second partition wall interposed therebetween. The pixel electrode and the charge injection transport layer are not arranged on at least one dummy light emitting element arranged in the peripheral region on the side where the recessed portion is present in each light emitting element row extending in the row direction. The display panel according to claim 2. The first step of preparing the board and
The second step of forming the flattening layer on the substrate and
A third step of forming a plurality of recessed portions at predetermined positions of the flattening layer, and
A fourth step of arranging a plurality of laminated bodies of a pixel electrode and a charge injection transport layer in a matrix on the flattening layer.
After forming a layer of the material of the second partition wall on the flattening layer and the laminated body, a second partition wall extending in the row direction is formed between a plurality of electrodes adjacent to each other in the column direction by a patterning process. 5 steps and
After forming a layer of the material of the first partition wall higher than the second partition wall on the flattening layer and the laminate, the material is stretched in the column direction between a plurality of electrodes adjacent to each other in the row direction by a patterning process. In addition, the sixth step of forming a plurality of first partition walls in which both ends in the row direction are connected by the connecting portion, and
The seventh step of applying ink containing a light emitting material to the gaps between the plurality of partition walls to form a light emitting layer, and
Including
The sixth step includes a step of cleaning with a cleaning liquid at the time of the patterning process and a step of removing the cleaning liquid.
The predetermined position where the plurality of recesses are provided in the third step is, in a plan view, within the gap between the plurality of first partition walls and at least one end side of the first partition wall in the row direction. A method of manufacturing a display panel, characterized in that it is located adjacent to a connecting portion. The step of removing the cleaning liquid in the sixth step includes a step of blowing the cleaning liquid toward one end in the row direction by wind pressure to remove the cleaning liquid.
In the third step, the predetermined position where the plurality of recessed portions are provided is within the gap between the plurality of first partition walls and adjacent to the connecting portion of the partition wall on the side where the cleaning liquid is blown, in a plan view. The method for manufacturing a display panel according to claim 9, wherein the position is to be used.

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