WO2012002268A1

WO2012002268A1 - Display device and production method for same

Info

Publication number: WO2012002268A1
Application number: PCT/JP2011/064522
Authority: WO
Inventors: 優梶谷; 元彦村上; 栗原　直; 雅之三木
Original assignee: 住友化学株式会社
Priority date: 2010-06-29
Filing date: 2011-06-24
Publication date: 2012-01-05
Also published as: JP2012014856A; TW201222722A

Abstract

Disclosed is a display device provided with inversely tapered partition walls and wherein a second electrode that extends across a plurality of organic EL elements is formed. The display device includes: a supporting substrate; partition walls which define pre-set sections on the supporting substrate; and a plurality of organic EL elements provided in each of the sections defined by the partition walls, with each organic EL element formed by laminating, in order from the supporting substrate side, a first electrode, an organic EL layer, and the second electrode. The partition walls are shaped to widen as the walls extend away from the supporting substrate. The second electrode is formed straddled across partition walls interposed between adjacent organic EL elements and extends across the plurality of organic EL elements. The film thickness of the second electrode is thicker than the interval, in the thickness direction of the supporting substrate, between the top surface of the partition walls and the interface between the second electrode and the organic EL layer.

Description

Display device and manufacturing method thereof

The present invention relates to a display device and a manufacturing method thereof.

There are various types of display devices with different configurations and principles. As one of them, a display device using an organic electroluminescence element (hereinafter sometimes referred to as an organic EL element) as a light source of a pixel is being put into practical use.

For example, in a color display device, three types of organic EL elements are provided on a supporting substrate as a light source of a pixel. That is, (1) a red organic EL element that emits red light, (2) a green organic EL element that emits green light, and (3) a blue organic EL element that emits blue light are provided on a support substrate, respectively. It is done. On the support substrate, a partition wall for defining a predetermined section is usually provided. The three types of organic EL elements are arranged in alignment with the partitions defined by the partition walls (that is, regions surrounded by the partition walls).

Each organic EL element is formed by sequentially laminating a first electrode, an organic electroluminescence layer (hereinafter sometimes referred to as an organic EL layer) and a second electrode in a region surrounded by a partition wall.

The above-described organic EL layer can be formed by, for example, a coating method. A method for forming the organic EL layer will be described with reference to FIG. As shown in FIG. 5A, ink 17 is supplied to a region 15 surrounded by the partition wall 13 in the support substrate 12 on which the first electrode 16 and the partition wall 13 are formed. The ink 17 includes a material for forming the organic EL layer 18 and a solvent. The supplied ink 17 is accommodated in a region 15 surrounded by the partition wall 13 (see FIG. 5B). And the organic EL layer 18 is formed when the solvent of the ink 17 evaporates (refer FIG. 5C).

When the partition wall 13 is lyophilic with respect to the ink 17, the ink supplied to the area surrounded by the partition wall 13 may flow along the surface of the partition wall 13 and overflow to the adjacent area. Therefore, on the support substrate 12, a partition wall 13 that normally exhibits a certain degree of liquid repellency with respect to the ink 17 is provided.

However, when the partition wall 13 is liquid repellent, the ink supplied to the region surrounded by the partition wall 13 evaporates while being repelled by the partition wall 13 to form a thin organic EL layer. Sometimes. For example, the portion of the organic EL layer 18 in contact with the partition wall 13, that is, the peripheral portion of the organic EL layer 18 may be thinner than the thickness of the central portion. In such a case, the electrical resistance of the peripheral part of the organic EL layer is lower than that of the central part. As a result, when a voltage is applied to the organic EL element, current may flow in a concentrated manner at the peripheral portion, and the central portion may be darker than the peripheral portion. Conversely, since the peripheral edge of the organic EL layer 18 is thinner than the intended thickness, the peripheral edge of the organic EL layer 18 may not emit light as intended.

In order to solve such a problem, there is a display device provided with a so-called reverse tapered partition. The schematic configuration is shown in FIG. The inversely tapered partition wall 13 is formed so as to become wider as it is separated from the support substrate 12. Therefore, the region defined by the side surface of the partition wall 13 and the surface of the first electrode 16 is configured to be tapered toward a portion where the partition wall 13 and the first electrode 16 are in contact (see FIG. 6A). When ink is supplied to the region 15 surrounded by the partition wall 13, even if the liquid-repellent partition wall 13 is provided, the ink that contacts the side surface of the partition wall 13 is caused by capillary action. It fills so that it may be suck | inhaled in the site | part which 1 electrode 16 and the partition 13 contact | connect. While the ink solvent evaporates while maintaining this state, an organic EL layer having a sufficient thickness is also formed at a portion where the first electrode and the partition wall are in contact with each other. Thus, by providing a so-called reverse taper-shaped partition wall, it is possible to prevent a problem that the peripheral edge portion of the organic EL layer becomes thinner than the thickness of the central portion (see FIG. 6B) (see, for example, Patent Document 1). ).

JP 2007-227289 A

In the display device, for example, the second electrode is provided as a common electrode for a plurality of organic EL elements. That is, the second electrode is formed continuously over the plurality of organic EL elements, and is also formed on the partition wall 13 interposed between adjacent organic EL elements. However, when the second electrode common to the plurality of organic EL elements is formed on the substrate provided with the reverse tapered partition wall 13 by, for example, vacuum deposition, the second electrode 19 is cut at the end of the partition wall 13. (See FIG. 6C). Therefore, the second electrode 19 that continues over a plurality of organic EL elements cannot be formed, and an element that cannot be driven to emit light may be formed without supplying power to the predetermined organic EL element.

Therefore, an object of the present invention is to provide a display device in which a second electrode connected to a plurality of organic EL elements is formed in a display device provided with an inversely tapered partition.

The present invention provides the following display device and manufacturing method thereof.
[1] a support substrate;
A partition that defines a predetermined section on the support substrate;
A plurality of organic electroluminescence elements respectively provided in the compartments defined by the partition walls, wherein each organic electroluminescence element includes a first electrode, an organic electroluminescence layer, and a second electrode in this order from the support substrate side. Including a plurality of organic electroluminescence elements configured by being laminated with,
The partition has a shape that becomes wider as it is separated from the support substrate,
The second electrode is formed over the partition interposed between adjacent organic electroluminescent elements, is continuous over the plurality of organic electroluminescent elements, and the film thickness of the second electrode is: A display device, which is thicker than a distance between a top surface of the partition wall and an interface between the second electrode and the organic electroluminescence layer in a thickness direction of a support substrate.
[2] The display device according to [1], wherein the partition has a lyophilic side surface compared to the top surface.
[3] A support substrate, a partition wall defining a partition set in advance on the support substrate, and a plurality of organic electroluminescence elements respectively provided in the partition defined by the partition wall, The luminescence element is a method of manufacturing a display device including a first electrode, an organic electroluminescence layer, and a plurality of organic electroluminescence elements configured by laminating a second electrode in this order from the support substrate side,
Preparing the support substrate on which the first electrode is formed;
Forming the partition having a shape that becomes wider as it is separated from the support substrate;
Forming the organic electroluminescence layer in each of the compartments defined by the partition;
Forming the second electrode extending across the plurality of organic electroluminescence elements across the partition interposed between adjacent organic electroluminescence elements, the top surface of the partition; and the first Forming the second electrode having a thickness greater than the distance between the two electrodes and the interface of the organic electroluminescence layer in the thickness direction of the support substrate;
A method for manufacturing a display device, comprising:
[4] In the step of forming the partition wall, an ink containing a photosensitive resin is applied onto the support substrate to form a partition wall forming film, and a predetermined portion of the partition wall forming film is exposed and further developed. The method for manufacturing a display device according to the above [3].
[5] The step of forming the organic electroluminescence layer supplies ink containing a material for forming the organic electroluminescence layer to each of the compartments defined by the partition walls, and solidifies the ink. The method for manufacturing a display device according to the above [3].
[6] The method for manufacturing a display device according to [3], wherein in the step of forming the partition wall, a partition wall whose side surface is more lyophilic than the top surface thereof is formed.
[7] The method for manufacturing a display device according to [4], wherein the ink including the photosensitive resin includes a liquid repellent material.

According to the present invention, it is possible to realize a display device in which a second electrode connected to a plurality of organic EL elements is formed in a display device including an inversely tapered partition.

FIG. 1 is a diagram schematically showing an enlarged part of a display device according to an embodiment of the present invention. FIG. 2 is a plan view schematically showing an enlarged part of a display device according to an embodiment of the present invention. FIG. 3A is a view for explaining a method for manufacturing a display device according to an embodiment of the present invention. FIG. 3B is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 3C is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 3D is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 4A is a view for explaining a method for manufacturing a display device according to an embodiment of the present invention. FIG. 4B is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 4C is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 4D is a view for explaining the method for manufacturing the display device according to the embodiment of the present invention. FIG. 5A is a diagram for explaining a method of manufacturing a display device using a coating method. FIG. 5B is a diagram for explaining a method of manufacturing a display device using a coating method. FIG. 5C is a diagram for explaining a method for manufacturing a display device using a coating method. FIG. 6A is a diagram for explaining a method of manufacturing a display device including a reverse-tapered partition. FIG. 6B is a diagram for explaining a method of manufacturing a display device including a reverse-tapered partition. FIG. 6C is a diagram for explaining a method of manufacturing a display device including a reverse-tapered partition wall.

DESCRIPTION OF SYMBOLS 1 Display apparatus 2 Support substrate 3 Partition 3a Top surface of partition 3b Side surface of partition 4 Organic EL element 5 Recess 6 First electrode 7 First organic EL layer (hole injection layer)
8 Partition formation film 9 Second organic EL layer (light emitting layer)
DESCRIPTION OF SYMBOLS 10 2nd electrode 12 Support substrate 13 Partition 15 Area | region surrounded by partition 16 1st electrode 17 Ink 18 Organic EL layer 19 2nd electrode 21 Photomask 22 Ink

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. For ease of understanding, the scale of each member in the drawings may be different from the actual scale. Further, the present invention is not limited by the following description, and can be appropriately changed without departing from the gist of the present invention. In the display device, there are members such as lead wires of electrodes, but the description thereof is omitted because it is not necessary to explain the present invention. For convenience of explanation of the layer structure and the like, in the example shown below, the explanation will be made together with the figure in which the support substrate is disposed below. It is not necessarily limited to the form in which it is arranged and manufactured or used, and may be adjusted as appropriate.

The display device according to the present invention includes a support substrate, a partition wall defining a partition set in advance on the support substrate, and a plurality of organic EL elements provided in each partition defined by the partition wall. The EL element includes a plurality of organic EL elements in which a first electrode, an organic EL layer, and a second electrode are stacked in this order from the support substrate side, and the partition wall is separated from the support substrate. Accordingly, the second electrode has a shape that becomes wider, and is formed across a partition wall interposed between adjacent organic EL elements, and extends across the plurality of organic EL elements. The thickness of the two electrodes is characterized by being thicker than the distance between the top surface of the partition and the interface between the second electrode and the organic EL layer in the thickness direction of the support substrate.

Display devices mainly include active matrix drive type devices and passive matrix drive type devices. Although the present invention can be applied to both types of display devices, in this embodiment, a display device applied to an active matrix drive type display device will be described as an example.

<Configuration of display device>
First, the configuration of the display device will be described. FIG. 1 is a diagram schematically showing an enlarged part of the display device 1 of the present embodiment. FIG. 2 is a plan view schematically showing an enlarged part of the display device 1 of the present embodiment. The display device 1 mainly includes a support substrate 2, partition walls 3 that define preset sections on the support substrate 2, and a plurality of organic EL elements 4 that are respectively provided in sections defined by the partition walls 3. It is comprised including.

The partition wall 3 is formed on the support substrate 2 in a lattice shape or a stripe shape, for example. FIG. 2 shows a display device 1 provided with a grid-like partition wall 3 as one embodiment. In the figure, the area where the partition walls 3 are provided is hatched.

A plurality of recesses 5 defined by the partition walls 3 and the support substrate 2 are set on the support substrate 2. The concave portion 5 corresponds to a section defined by the partition wall 3.

The partition wall 3 of this embodiment is provided in a lattice shape. Therefore, when viewed from one side in the thickness direction Z of the support substrate 2 (hereinafter sometimes referred to as “in plan view”), the plurality of recesses 5 are arranged in a matrix. That is, the recesses 5 are provided with a predetermined interval in the row direction X and aligned in the column direction Y with a predetermined interval. The shape of each recess 5 in plan view is not particularly limited. For example, the recess 5 may be formed in a shape such as a substantially rectangular shape, a substantially oval shape, or an oval shape in plan view. In the present embodiment, a substantially rectangular recess 5 is provided in plan view. In the present specification, the row direction X and the column direction Y mean directions perpendicular to the thickness direction Z of the support substrate and perpendicular to each other.

In still another embodiment, when a stripe-shaped partition is provided, the partition is configured by, for example, a plurality of partition members extending in the row direction X being arranged at a predetermined interval in the column direction Y. In this embodiment, a stripe-shaped recess is defined by the stripe-shaped partition wall and the support substrate.

The partition wall has a shape that becomes wider as it is separated from the support substrate. For example, when the partition walls extending in the column direction Y are cut along a plane perpendicular to the extending direction (column direction Y), the cross-sectional shape has a shape that becomes wider as the distance from the support substrate increases. FIG. 1 shows an isosceles trapezoidal partition wall. When the upper base and the lower base on the support substrate side are compared, the upper base is wider than the lower base. In addition, the cross section of the partition actually formed does not necessarily have a trapezoidal shape, and the straight part and corners of the trapezoidal shape may be rounded.

The angle θ formed by the side surface 3b of the partition wall 3 and the surface of the support substrate, that is, the inclination angle θ of the partition wall side surface 3b is about 10 ° to 85 °, and preferably 50 ° to 70 °. The partition wall 3 having an inclination angle θ of 0 to 90 ° on the partition wall side surface 3b is called a so-called reverse tapered partition wall, and the partition wall 3 having an inclination angle θ on the partition wall side surface 3b of 90 ° to 180 ° is so-called forward. It is called a tapered partition. That is, in this embodiment, the inversely tapered partition wall 3 is provided.

It is preferable that the side wall 3b of the partition wall 3 is more lyophilic than the top surface 3a. The top surface 3 a of the partition wall 3 means a surface that is present at a position farthest from the support substrate 2 in the surface of the partition wall 3. Moreover, the side surface of the partition 3 means the surface which exists in the position which faces the adjacent partition among the surfaces of the partition 3. FIG. The degree of liquid repellency or lyophilicity of the partition wall 3 with respect to the ink can be expressed by the contact angle between the ink supplied to the recess 5 and the partition wall 3. For example, the top surface 3a of the partition wall 3 preferably has a contact angle with anisole of 30 ° or more. Further, the side surface 3b is more lyophilic than the top surface 3a of the partition wall 3. For example, the contact angle between the anisole and the side surface 3b of the partition wall 3 is greater than the contact angle between the anisole and the top surface 3a of the partition wall 3. Mean small. Since the top surface 3a of the partition wall 3 is liquid repellent, the ink supplied to the region (recessed portion 5) surrounded by the partition wall 3 flows along the top surface 3a of the partition wall 3 and overflows to the adjacent region. Can be prevented. Further, since the side surface 3b of the partition wall 3 is lyophilic, the ink supplied to the region surrounded by the partition wall 3 can be prevented from being repelled by the side surface 3b of the partition wall 3, and the partition wall 3 and the first electrode can be prevented. The ink can be easily filled up to the portion where the ink 7 contacts. This can prevent the peripheral portion of the organic EL layer from becoming thinner than the central portion.

The organic EL element 4 is provided in a section defined by the partition 3 (that is, the recess 5). When the grid-like partition 3 is provided as in the present embodiment, each organic EL element 4 is provided in each recess 5. That is, the organic EL elements 4 are arranged in a matrix like the concave portions 5 and are arranged on the support substrate 2 with a predetermined interval in the row direction X and with a predetermined interval in the column direction Y. Is provided.

As another embodiment, when stripe-shaped partition walls are provided, the organic EL elements 4 are arranged at predetermined intervals in the row direction X in the respective recesses extending in the row direction X.

In the present embodiment, three types of organic EL elements 4 are provided. That is, (1) a red organic EL element 4R that emits red light, (2) a green organic EL element 4G that emits green light, and (3) a blue organic EL element 4B that emits blue light are provided. These three types of

organic EL elements

4R, 4G, and 4B are arranged in alignment, for example, by repeatedly arranging the following rows (I), (II), and (III) in this order in the column direction Y. (See FIG. 2).
(I) Rows in which the red organic EL elements 4R are arranged at predetermined intervals in the row direction X.
(II) Rows in which the green organic EL elements 4G are arranged at predetermined intervals in the row direction X.
(III) A row in which the blue organic EL elements 4B are arranged at predetermined intervals in the row direction X.

As another embodiment, in addition to the above three types of organic EL elements, for example, an organic EL element that emits white light may be further provided. In addition, a monochrome display device may be realized by providing only one type of organic EL element.

The organic EL element 4 is configured by laminating a first electrode, an organic EL layer, and a second electrode in this order from the support substrate side. In the present specification, one or a plurality of layers provided between the first electrode 6 and the second electrode 10 are each referred to as an organic EL layer. The organic EL element 4 includes at least one light emitting layer as an organic EL layer. The organic EL element may further include an organic EL layer different from the light emitting layer, if necessary, in addition to the single light emitting layer. For example, a hole injection layer, a hole transport layer, an electron block layer, an electron transport layer, and an electron injection layer may be provided between the first electrode 6 and the second electrode 10 as an organic EL layer. Good. Two or more light emitting layers may be provided between the first electrode 6 and the second electrode 10.

The organic EL element 4 includes a first electrode 6 and a second electrode 10 as a pair of electrodes including an anode and a cathode. One of the first electrode 6 and the second electrode 10 is provided as an anode, and the other electrode is provided as a cathode.

In this embodiment, as an example, the first electrode 6 functioning as an anode, the first organic EL layer 7 functioning as a hole injection layer, the second organic EL layer 9 functioning as a light emitting layer, and the second functioning as a cathode. The organic EL element 4 configured by laminating the electrodes 10 on the support substrate 2 in this order will be described.

In this embodiment, three types of organic EL elements are provided, but these have different configurations of the second organic EL layer (light emitting layer in the present embodiment) 9. The red organic EL element 4R includes a red light emitting layer 9R that emits red light. The green organic EL element 4G includes a green light emitting layer 9G that emits green light. The blue organic EL element 4B includes a blue light emitting layer 9B that emits blue light.

In the present embodiment, the first electrode 6 is provided for each organic EL element 4. That is, the same number of first electrodes 6 as the organic EL elements 4 are provided on the support substrate 2. The first electrodes 6 are provided corresponding to the arrangement of the organic EL elements 4 and are arranged in a matrix like the organic EL elements 4. In addition, although the partition 3 of this embodiment is mainly formed in a grid pattern in a region excluding the first electrode 6, it is further formed so as to cover the peripheral edge of the first electrode 6 (see FIG. 1).

The first organic EL layer 7 functioning as a hole injection layer is provided on the first electrode 6 in the recess 5. The first organic EL layer 7 is provided with a different material or film thickness depending on the type of the organic EL element, if necessary. In addition, from a viewpoint of the simplicity of the formation process of the 1st organic EL layer 7, you may form all the 1st organic EL layers 7 with the same material and the same film thickness.

The second organic EL layer 9 functioning as a light emitting layer is provided on the first organic EL layer 7 in the recess 5. As described above, the light emitting layer is provided according to the type of the organic EL element. That is, the red light emitting layer 9R is provided in the recess 5 where the red organic EL element 4R is provided. The green light emitting layer 9G is provided in the recess 5 in which the green organic EL element 4G is provided. The blue light emitting layer 9B is provided in the recess 5 where the blue organic EL element 4B is provided.

The second electrode 10 is formed on the entire display area where the organic EL element 4 is provided. That is, the second electrode 10 is formed not only on the second organic EL layer 9 but also on the partition 3 and continuously formed over a plurality of organic EL elements.

The second electrode 10 is formed in the thickness direction Z of the support substrate between the top surface 3 a of the partition wall 3 and the interface between the second electrode 10 and the organic EL layer (second organic EL layer in this embodiment) 9. The film thickness L2 is thicker than the interval L1. By forming the second electrode 10 thick in this way, the second electrode 10 formed on the partition 3 and the second electrode 10 formed on the first organic EL layer 9 are inevitably physically formed. Will be connected. The difference (L2−L1) may be a value larger than 0 μm. In order to reduce the electrical resistance of the second electrode 10, the difference (L2−L1) is preferably 0.2 μm or more. The upper limit value of the difference (L2−L1) is not particularly set, but if the film thickness is too thick, the time required to form the second electrode 10 becomes longer, and therefore the difference (L2−L1) is 1 μm or less. Is preferred.

In the above embodiment, the partition 3 is provided in contact with the support substrate 2 so as to cover the peripheral edge of the first electrode 6. As another embodiment, an insulating film may be further provided between the partition wall 3 and the support substrate 2. For example, the insulating film is formed in a lattice shape like the partition wall, and is formed so as to cover the periphery of the first electrode 6. Such an insulating film is preferably formed of a material that is more lyophilic than the partition 3.

Hereinafter, a method for manufacturing a display device will be described with reference to FIGS.

(Process for preparing support substrate)
In this step, the first electrode 6 is formed on the support substrate 2 (see FIG. 3A). In this step, the support substrate 2 on which the first electrode 6 is formed may be prepared by obtaining from the market a support substrate on which the first electrode 6 is formed.

In the case of an active matrix display device, a substrate on which circuits for individually driving a plurality of organic EL elements are formed in advance may be used as the support substrate 2. For example, a substrate on which a TFT (Thin Film Transistor) and a capacitor are formed in advance may be used as the support substrate.

First, a plurality of first electrodes 6 are formed in a matrix on the support substrate 2. The first electrode 6 may be formed, for example, by forming a conductive thin film on one surface of the support substrate 2 and patterning it in a matrix by a photolithography method. Further, for example, a mask having an opening formed in a predetermined portion is disposed on the support substrate 2, and a conductive material is selectively deposited on the predetermined portion on the support substrate 2 through the mask, thereby the first electrode 6. The pattern may be formed. The material of the first electrode 6 will be described later.

(Step of forming partition walls)
In this step, a partition wall having a shape that becomes wider as the distance from the support substrate increases. This step may be carried out by applying a film containing an ink containing a photosensitive resin onto the support substrate, exposing a predetermined portion, and further developing.

First, an ink containing a photosensitive resin is applied and formed on the support substrate (see FIG. 3B). In the present embodiment, as a preferred embodiment, the partition wall 3 is formed such that the side surface 3b is more lyophilic than the top surface 3a. Such a partition may be formed, for example, by applying an ink containing a liquid repellent material on the support substrate 2. That is, the ink containing the photosensitive resin may further contain a liquid repellent material.

Examples of the ink application method include spin coating and slit coating.

After the ink containing the photosensitive resin is applied and formed on the support substrate, it is usually pre-baked. For example, pre-baking is performed by heating the substrate at a temperature of 80 ° C. to 110 ° C. for 60 seconds to 180 seconds to remove the solvent in the ink (see FIG. 3B). When the ink contains a liquid repellent material, the liquid repellent material is aggregated on the surface 8 a of the partition forming film 8 formed in this way.

Next, a photomask 21 that shields light of a predetermined pattern is arranged on the support substrate, and the partition wall forming film 8 is exposed through the photomask 21. The photosensitive resin includes a positive type resin and a negative type resin, and any resin may be used in this step. In the case where a positive photosensitive resin is used, light is irradiated to the remaining part of the partition forming film 8 except the part where the partition 3 is to be formed. In the case where a negative photosensitive resin is used, light is irradiated to a part of the partition forming film 8 where the partition 3 is to be formed. In this step, a case where a negative photosensitive resin is used will be described with reference to FIG. 3C. As shown in FIG. 3C, a photomask 21 is arranged on the substrate on which the partition wall forming film 8 is formed, and light is irradiated through the photomask 21, whereby the partition wall forming film 8 mainly includes the partition wall. 3 is irradiated with light. In FIG. 3C, the light applied to the partition wall forming film 8 is schematically indicated by an arrow symbol.

Next, the exposed barrier rib forming film 8 is developed. Thereby, the partition 3 is patterned (see FIG. 3D). After development, post-bake is performed as necessary. For example, post-baking is performed by heating the substrate at a temperature of 200 ° C. to 230 ° C. for 15 to 60 minutes to cure the partition walls 3.

As described above, when the partition wall is formed using the ink containing the liquid repellent material, the liquid repellent material aggregates on the surface 8a of the partition wall forming film 8, and therefore, compared to the top surface 3a, The partition wall 3 whose side surface 3b is lyophilic is obtained.

In the present embodiment, the so-called reverse-tapered partition wall 3 having the inclination angle θ of the partition wall side surface 3b ranging from 0 ° to 90 ° is formed. However, the inclination angle θ of the partition wall side surface 3b can be changed by adjusting the following factors, for example. Can be made.

The inclination angle θ of the side wall 3b is mainly determined by the type of photosensitive resin used. Therefore, a photosensitive resin to be an inversely tapered partition is selected from a plurality of types of photosensitive resins, and the partition may be formed using this. The inclination angle θ of the partition wall side surface 3b can also be adjusted by adjusting the development time. In general, in the case of a negative photosensitive resin, the inclination angle θ of the partition wall side surface 3b tends to be smaller as the development time is longer. The inclination angle θ of the partition wall side surface 3b can also be adjusted by adjusting the exposure amount. In general, in the case of a negative photosensitive resin, the inclination angle θ of the partition wall side surface 3b tends to increase as the exposure amount decreases. The inclination angle θ of the partition wall side surface 3b can also be adjusted by adjusting the distance between the photomask and the substrate. In general, in the case of a negative photosensitive resin, the inclination angle θ of the partition wall side surface 3b tends to increase as the distance between the photomask and the substrate decreases.

Examples of the photosensitive resin used for forming the partition include a negative type and a positive type.
In the negative photosensitive resin, the irradiated portion remains insoluble in the developer.

Ink containing a photosensitive resin generally contains a binder resin, a crosslinking agent, a photoreaction initiator, a solvent, and other additives.
The binder resin is polymerized in advance. Examples thereof include a non-polymerizable binder resin that does not have self-polymerizability and a polymerizable binder resin into which a substituent having polymerizability is introduced. The binder resin has a weight average molecular weight in the range of 5,000 to 400,000 determined by gel permeation chromatography (GPC) using polystyrene as a standard.
Examples of the binder resin include phenol resin, novolac resin, melamine resin, acrylic resin, epoxy resin, and polyester resin. As the binder resin, either a homopolymer or a copolymer obtained by combining two or more monomers may be used. The binder resin is usually 5% to 90% in mass fraction with respect to the total solid content of the ink containing the photosensitive resin.

The crosslinking agent is a compound that can be polymerized by an active radical, an acid, or the like generated from the photopolymerization initiator by light irradiation, and examples thereof include a compound having a polymerizable carbon-carbon unsaturated bond. The cross-linking material may be a monofunctional compound having one polymerizable carbon-carbon unsaturated bond in the molecule, or a bifunctional or trifunctional compound having two or more polymerizable carbon-carbon unsaturated bonds. The above polyfunctional compounds may be used. In the ink containing the photosensitive resin, the crosslinking agent is usually 0.1 parts by mass or more and 70 parts by mass or less when the total amount of the binder resin and the crosslinking agent is 100 parts by mass. Moreover, in the ink containing the said photosensitive resin, a photoinitiator is 1 mass part or more and 30 mass parts or less normally, when the total amount of binder resin and a crosslinking agent is 100 mass parts.

On the other hand, in the positive type photosensitive resin, the irradiated portion is solubilized in the developer. The positive photosensitive resin is generally constituted by combining a resin and a compound that becomes hydrophilic by a photoreaction.

As the positive photosensitive resin, a combination of a resin having chemical resistance and adhesion such as novolac resin, polyhydroxystyrene, acrylic resin, methacrylic resin, polyimide, and a photodegradable compound may be used. .

Also, examples of the liquid repellent material that may be used in this step include fluorine-containing compounds, silicone-containing compounds, and combinations thereof. Preferably, it is a fluorine-containing compound that exhibits excellent liquid repellency even with respect to organic solvents.

Examples of the fluorine-containing compound include compounds having a linear or branched fluoroalkyl group and / or fluoropolyether group having 1 to 8 carbon atoms. The fluorine-containing compound is preferably a polymer having a crosslinkable group, and more preferably a polymer having a fluoroalkyl group and / or fluoropolyether group having 4 to 6 carbon atoms and having a crosslinkable group. Alternatively, the fluorine-containing compound preferably has a soluble function in the developer. The fluorine-containing compound is not limited to a polymer and may be a low molecular compound as long as it can impart liquid repellency to the partition wall surface after the partition wall is formed.

The crosslinkable group imparts a crosslinkable function to the fluorine-containing compound, and examples thereof include an ethylenically unsaturated bond group, an epoxy group, and a hydroxyl group. The type of the crosslinkable group is not limited to the above as long as it has a function of crosslinking with the photosensitive resin used for forming the partition wall.

Specific examples of the liquid repellent material include Megafax RS-101, RS-102, RS-105, RS-401, RS-402, RS-501, RS-502, RS-718 (above, manufactured by DIC) ), Optool DAC, Optoace HP series (manufactured by Daikin Industries, Ltd.), perfluoro (meth) acrylate, perfluorodi (meth) acrylate, and the like.
One of these liquid repellent materials may be used alone, or two or more of them may be used in combination. The liquid repellent material is usually 0.1 to 3 parts by mass with respect to the total solid content of the ink containing the photosensitive resin.

In one embodiment, the ink containing a photosensitive resin comprises a photosensitive resin, a liquid repellent material, and a solvent. As described above, the ink containing the photosensitive resin may further contain a binder resin, a crosslinking agent, a photoreaction initiator, and other additives.

Examples of the developer used for development include an aqueous potassium chloride solution and an aqueous tetramethylammonium hydroxide (TMAH) solution.

The shape of the partition 3 and the arrangement thereof are appropriately set according to the specifications of the display device such as the number of pixels and the resolution, the ease of manufacturing, and the like. For example, the width of the partition wall 3 in the row direction X or the column direction Y is about 5 μm to 50 μm, the height of the partition wall 3 is about 0.5 μm to 5 μm, and the partition walls 3 adjacent to each other in the row direction X or the column direction Y , That is, the width of the recess 5 in the row direction X or the column direction Y is about 10 μm to 200 μm. The width of the first electrode 6 in the row direction X or the column direction Y is about 10 μm to 200 μm, respectively.

(Process of forming organic EL layer)
In this step, an organic EL layer is formed in each of the sections defined by the partition walls. In this step, at least one organic EL layer among the one or more organic EL layers is formed by a coating method. In the embodiment described below, the first organic EL layer 7 and the second organic EL layer 9 are formed by a coating method.

First, the ink 22 containing the material for forming the first organic EL layer 7 is supplied to the region (recessed portion 5) surrounded by the partition walls 3 (see FIG. 4A). The ink is appropriately supplied by an optimum method in consideration of conditions such as the shape of the partition wall 3, the simplicity of the film forming process, and the film forming property. The ink may be supplied by, for example, an inkjet printing method, a nozzle coating method, a relief printing method, an intaglio printing method, or the like.

Next, the first organic EL layer 7 is formed by solidifying the supplied ink 22 (see FIG. 4B). The ink may be solidified by, for example, natural drying, heat drying, or vacuum drying. Also, when the ink contains a material that polymerizes by applying energy, after supplying the ink, the material constituting the organic EL layer is polymerized by heating the thin film or irradiating the thin film with light. Also good. By polymerizing the material constituting the organic EL layer in this manner, another organic EL layer (hereinafter also referred to as a second organic EL layer) is formed on the organic EL layer (hereinafter also referred to as a first organic EL layer). The first organic EL layer can be hardly solubilized with respect to the ink used for further forming the above.

Next, a second organic EL layer 9 that functions as a light emitting layer is formed. The second organic EL layer 9 may be formed in the same manner as the first organic EL layer 7. That is, three types of inks, ink containing a material for forming the red light emitting layer 9R, ink containing a material for forming the green light emitting layer 9G, and ink containing a material for forming the blue light emitting layer 9B, The light emitting layers 9R, 9G, and 9B may be formed by supplying each of the regions surrounded by the partition walls 3 and solidifying them.

(Step of forming the second electrode)
Next, the second electrode 10 is formed. In this step, the second electrode 10 having a thickness greater than the distance between the top surface of the partition and the interface between the second electrode 10 and the organic EL layer in the thickness direction of the support substrate is formed (see FIG. 4D). By forming the thick second electrode 10 in this way, the second electrode 10 formed on the partition 3 is inevitably connected to the second electrode 10 formed on the first organic EL layer 9. Is done. As a result, the second electrode is formed across the plurality of organic EL elements across the partition 3 interposed between adjacent organic EL elements.

As described above, by forming the thick second electrode 10, it is possible to prevent the second electrode 10 from being cut at the end of the partition 3, even if the inversely tapered partition 3 is provided. The second electrode 10 that extends over all the organic EL elements 4 can be formed.

Further, since the inversely tapered partition is provided, the ink 22 supplied to the region (recessed portion 5) surrounded by the partition 3 is sucked into the portion where the first electrode 16 and the partition 13 are in contact by capillary action. Filled. While the ink solvent evaporates while maintaining this state, an organic EL layer having a sufficient thickness is also formed at a portion where the first electrode and the partition wall are in contact with each other. Thereby, an organic EL layer having a uniform film thickness can be obtained.

Further, since the top surface 3a of the partition wall 3 is liquid repellent, the ink 22 supplied to the region (recessed portion 5) surrounded by the partition wall 3 is repelled by the top surface 3a of the partition wall 3 (see FIG. 4A). For this reason, it is possible to prevent the ink 22 from flowing over the top surface 3a of the partition wall 3 and overflowing to the adjacent region, and the ink can be contained in the region (recessed portion 5) surrounded by the partition wall 3. Further, since the side surface 3b of the partition wall 3 is lyophilic, the ink supplied to the region surrounded by the partition wall 3 can be prevented from being repelled by the side surface 3b of the partition wall 3, and the partition wall 3 and the first electrode can be prevented. The ink can be more easily filled up to the portion where the contact is made. Thereby, an organic EL layer having a more uniform film thickness can be obtained.

In this embodiment, in order to impart liquid repellency to the top surface 3a of the partition wall 3, the partition wall is formed using ink containing a liquid repellent material. However, the top surface 3a of the partition wall 3 is repelled by other methods. Liquidity may be imparted. As another method, for example, a method of performing plasma treatment in an atmosphere containing fluoride can be cited. In this method, since the plasma atmosphere is introduced, the process becomes complicated and the manufacturing cost may increase. Further, the first electrode 6 may be contaminated by the plasma treatment, and this plasma treatment may cause a decrease in yield. In contrast, in the present embodiment in which the partition walls are formed using ink containing a liquid-repellent material, the partition walls can be formed without performing plasma treatment, which improves yield and reduces manufacturing costs. Can do.

<Configuration of organic EL element>
Below, the structure of an organic EL element is demonstrated in detail. The organic EL element has at least one light emitting layer as an organic EL layer. As described above, the organic EL element may have, for example, a hole injection layer, a hole transport layer, an electron block layer, a hole block layer, an electron transport layer, and an electron injection layer as the organic EL layer.

An example of a layer structure that can be taken by the organic EL element of the present embodiment is shown below.
a) anode / light emitting layer / cathode b) anode / hole injection layer / light emitting layer / cathode c) anode / hole injection layer / light emitting layer / electron injection layer / cathode d) anode / hole injection layer / light emitting layer / Electron transport layer / cathode e) anode / hole injection layer / light emitting layer / electron transport layer / electron injection layer / cathode f) anode / hole transport layer / light emitting layer / cathode g) anode / hole transport layer / light emitting layer / Electron injection layer / cathode h) anode / hole transport layer / light emitting layer / electron transport layer / cathode i) anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode j) anode / hole Injection layer / hole transport layer / light emitting layer / cathode k) anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode l) anode / hole injection layer / hole transport layer / light emitting layer / Electron transport layer / cathode m) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode n) anode / light emitting layer / electron injection layer / cathode o) anode / Photo layer / electron transport layer / cathode p) anode / light emitting layer / electron transport layer / electron injection layer / cathode (here, the symbol “/” indicates that the layers sandwiching the symbol “/” are stacked adjacent to each other) Indicates.
same as below. )

In the above-described embodiment, the organic EL element in which the first electrode that functions as the anode is disposed closer to the support substrate has been described. However, in the present invention, the first electrode that functions as the cathode is closer to the support substrate. The present invention can also be applied to an organic EL element arranged on the side.

<Support substrate>
As the support substrate, a substrate that is not chemically changed in the process of manufacturing the organic EL element is suitably used. Examples of the material for the support substrate include glass, plastic, polymer film, silicon plate, and laminates thereof.

<Anode>
In the case of an organic EL element having a configuration in which light emitted from the light emitting layer is emitted to the outside through the anode, an electrode exhibiting optical transparency is used for the anode. As the electrode exhibiting light transmittance, for example, a thin film made of a material such as metal oxide, metal sulfide, and metal can be used, and an electrode having high electrical conductivity and light transmittance is preferably used. Specifically, a thin film made of indium oxide, zinc oxide, tin oxide, ITO, indium zinc oxide (abbreviated as IZO), gold, platinum, silver, copper, or the like is used. Among these, ITO, IZO Or a thin film made of tin oxide is preferably used. Examples of the method for producing the anode include a vacuum deposition method, a sputtering method, an ion plating method, and a plating method. Further, an organic transparent conductive film such as polyaniline or a derivative thereof, polythiophene or a derivative thereof may be used as the anode.

<Cathode>
A material for the cathode is preferably a material having a low work function, easy electron injection into the light emitting layer, and high electrical conductivity. Further, in the organic EL element configured to extract light from the anode side, the cathode material is preferably a material having a high reflectance with respect to visible light in order to reflect light emitted from the light emitting layer to the anode side by the cathode. Examples of such cathode materials include metals, alloys, graphite, and graphite intercalation compounds. Examples of the metal include alkali metals, alkaline earth metals, transition metals, and metals of Group 13 of the periodic table. Specific examples include lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, Aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, ytterbium, and the like can be given. Examples of the alloy include an alloy of two or more of the metals; and one or more of the metals, gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, and tin. Examples thereof include alloys with one or more metals selected from the group consisting of magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesium. Alloy, lithium-indium alloy, calcium-aluminum alloy and the like. The cathode may be a transparent electrode, and examples of the material thereof include conductive metals such as indium oxide, zinc oxide, tin oxide, indium tin oxide (ITO), and indium zinc oxide (IZO). Oxides; conductive organic substances such as polyaniline or derivatives thereof, polythiophene or derivatives thereof, and the like. The cathode may have a stacked structure in which two or more layers are stacked. The electron injection layer may be used as a cathode.

Examples of the method for producing the cathode include a vacuum deposition method and an ion plating method.

The film thickness of the anode or cathode may be appropriately set in consideration of the required characteristics and the simplicity of the film forming process, and is, for example, 10 nm to 10 μm, preferably 20 nm to 1 μm, and more preferably 50 nm to 500 nm. It is. As described above, of the anode and the cathode, the electrode corresponding to the second electrode is more than the distance in the thickness direction of the support substrate between the top surface of the partition and the interface between the second electrode and the organic EL layer. It is formed so that the film thickness becomes thick.

<Hole injection layer>
Examples of the hole injection material constituting the hole injection layer include oxides such as vanadium oxide, molybdenum oxide, ruthenium oxide, and aluminum oxide; phenylamine compounds; starburst amine compounds; phthalocyanine compounds; amorphous carbon Polyaniline; and polythiophene derivatives.

Examples of the method for forming the hole injection layer include film formation from a solution containing a hole injection material. For example, a hole injection layer may be formed by coating a film containing a hole injection material by a predetermined coating method and solidifying the solution.

The thickness of the hole injection layer may be appropriately set in consideration of the required characteristics and the simplicity of the process, and is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, more preferably 5 nm to 200 nm. is there.

<Hole transport layer>
Examples of the hole transport material constituting the hole transport layer include polyvinyl carbazole or derivatives thereof, polysilane or derivatives thereof, polysiloxane derivatives having aromatic amines in side chains or main chains, pyrazoline derivatives, arylamine derivatives, stilbene derivatives. , Triphenyldiamine derivative, polyaniline or derivative thereof, polythiophene or derivative thereof, polyarylamine or derivative thereof, polypyrrole or derivative thereof, poly (p-phenylene vinylene) or derivative thereof, and poly (2,5-thienylene vinylene) Or the derivative | guide_body etc. are mentioned.

The thickness of the hole transport layer may be set in consideration of the required characteristics and the simplicity of the film forming process, and is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm. It is.

<Light emitting layer>
The light emitting layer usually contains an organic substance that mainly emits fluorescence and / or phosphorescence. The light emitting layer may further include a dopant that assists the organic matter. The dopant is added, for example, in order to improve the luminous efficiency and change the emission wavelength. In addition, the organic substance which comprises a light emitting layer may be a low molecular compound or a high molecular compound, and when forming a light emitting layer by the apply | coating method, it is preferable that it is a high molecular compound. The number average molecular weight in terms of polystyrene of the polymer compound may be, for example, about 10 ³ to 10 ⁸ . Examples of the light emitting material constituting the light emitting layer include the following dye materials, metal complex materials, polymer materials, and dopant materials.

(Dye material)
Examples of dye-based materials include cyclopentamine derivatives, tetraphenylbutadiene derivative compounds, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, pyrrole derivatives, thiophene ring compounds. Pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, oxadiazole dimers, pyrazoline dimers, quinacridone derivatives, and coumarin derivatives.

(Metal complex materials)
Examples of metal complex materials include central metals such as rare earth metals (eg, Tb, Eu, Dy), Al, Zn, Be, Ir, Pt, oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structures, and the like. And a metal complex having the above ligand. Examples of such metal complexes include metal complexes that emit light from triplet excited states such as iridium complexes and platinum complexes, aluminum quinolinol complexes, benzoquinolinol beryllium complexes, benzoxazolyl zinc complexes, benzothiazole zinc complexes, azomethyl zinc complexes. , Porphyrin zinc complex, phenanthroline europium complex, and the like.

(Polymer material)
Examples of polymer materials include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and the above-mentioned dye materials and metal complex light emitting materials. And the like.

The thickness of the light emitting layer is usually about 2 nm to 200 nm.

<Electron transport layer>
As the electron transport material constituting the electron transport layer, known materials can be used, such as oxadiazole derivatives, anthraquinodimethane or derivatives thereof, benzoquinone or derivatives thereof, naphthoquinone or derivatives thereof, anthraquinones or derivatives thereof, tetracyano Anthraquinodimethane or derivative thereof, fluorenone derivative, diphenyldicyanoethylene or derivative thereof, diphenoquinone derivative, or metal complex of 8-hydroxyquinoline or derivative thereof, polyquinoline or derivative thereof, polyquinoxaline or derivative thereof, polyfluorene or derivative thereof, etc. Is mentioned.

The film thickness of the electron transport layer may be appropriately set in consideration of required characteristics and the simplicity of the film forming process, and is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm. It is.

<Electron injection layer>
The electron injecting material constituting the electron injecting layer may be appropriately selected according to the type of the light emitting layer. For example, alkali metal; alkaline earth metal; alloy containing one or more of the metals; oxide of the metal , Halides and carbonates; and mixtures of the aforementioned substances. Examples of the alkali metal and its oxide, halide, and carbonate include lithium, sodium, potassium, rubidium, cesium, lithium oxide, lithium fluoride, sodium oxide, sodium fluoride, potassium oxide, potassium fluoride, Examples thereof include rubidium oxide, rubidium fluoride, cesium oxide, cesium fluoride, and lithium carbonate. Examples of the alkaline earth metals and oxides, halides and carbonates thereof include magnesium, calcium, barium, strontium, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, barium oxide, fluoride. Examples include barium, strontium oxide, strontium fluoride, and magnesium carbonate. The electron injection layer may have a stacked structure in which two or more layers are stacked, and specific examples include LiF / Ca.

The thickness of the electron injection layer is preferably about 1 nm to 1 μm.

Examples of the method for forming each organic EL layer include a coating method such as a nozzle printing method, an inkjet printing method, a relief printing method, and an intaglio printing method; a vacuum deposition method; a sputtering method; and a CVD method. As described above, in the method for manufacturing a display device of the present invention, at least one organic EL layer is formed by a coating method among one or more organic EL layers.

In the coating method, an organic EL layer is formed by coating and forming an ink containing an organic EL material to be each organic EL layer and solidifying the ink. Examples of the solvent of the ink used in the coating method include chlorine solvents such as chloroform, methylene chloride, and dichloroethane; ether solvents such as tetrahydrofuran; aromatic hydrocarbon solvents such as toluene and xylene; ketones such as acetone and methyl ethyl ketone. System solvents; ester solvents such as ethyl acetate, butyl acetate and ethyl cellosolve acetate; and water.

Example 1
First, a TFT substrate on which a first electrode (anode) made of an ITO thin film was previously patterned was prepared (see FIG. 3 (1)).

Next, the negative photosensitive resin solution (ZPN2464 manufactured by ZEON Corporation) is mixed with the liquid repellent 2 (Daikin's liquid repellent Opt-Ace (registered commercial method) HP series) to prepare a photosensitive resin solution containing the liquid repellent material. did. The solid content concentration ratio of the liquid repellent to the photosensitive resin was 0.2% (weight). Next, a photosensitive resin solution containing a liquid repellent material is applied and formed on the surface of the prepared TFT substrate by a spin coater, and further prebaked by heating on a hot plate at 110 ° C. for 90 seconds to remove the solvent. It evaporated (refer FIG. 3 (2)).

Next, it exposes with the exposure amount of 100 mJ / cm < ² > using a proximity exposure machine (refer FIG. 3 (3)), and is 100 using a developing solution (SD-1 (TMAH2.38 wt%) made by Tokuyama Corporation) after that. Developed for seconds. Furthermore, it heated at 230 degreeC as post-baking for 30 minutes, the resin was hardened, and the reverse-tapered partition was formed (refer FIG. 3 (4)). The partition wall thickness was 1.0 μm. The inclination angle θ of the partition wall side surface 3b was 65 °. The contact angle between the partition wall top surface and pure water was 75 °, and the contact angle between the partition wall top surface and anisole was 39 °. The contact angle between the surface of the first electrode (ITO thin film) and pure water was 25 °.

Next, a hole injection layer was formed as a first organic EL layer. First, the surface of the substrate was washed with ozone water (concentration: 10 ppm, treatment time: 15 minutes) using an ozone water production apparatus (FA-1000ZW12-5C manufactured by Loki Techno Co., Ltd.). By this cleaning, the contact angle between the surface of the first electrode (ITO thin film) and pure water was reduced to 5 ° or less, and sufficient wettability could be imparted to the surface of the first electrode (ITO thin film). Next, an ink (poly (ethylenedioxythiophene) (PEDOT) / polystyrene sulfonic acid (PSS) aqueous dispersion with a solid content concentration of 1.5% by weight (AI 4083 manufactured by Bayer) using an inkjet apparatus (Litlex 142P manufactured by ULVAC). ) Was applied to each recess (see FIG. 4A). Since the ink was repelled by the top surface of the partition wall having a large contact angle with the ink, the ink was prevented from overflowing to the adjacent region through this top surface and was accommodated in the recess. On the other hand, the ink accommodated in the concave portion was filled so as to be sucked into a portion where the first electrode and the partition wall were in contact with each other by capillary action, and spread uniformly in the concave portion. The substrate was baked at 200 ° C. to form a hole injection layer (film thickness of 50 nm) with a uniform film thickness (see FIG. 4B).

Next, three types of light emitting layers were formed. First, the polymer light emitting material 1 that emits red light was mixed with an organic solvent so that the concentration thereof was 0.8 wt% to prepare red ink. Similarly, the polymer light-emitting material 2 that emits green light was mixed with an organic solvent so that its concentration was 0.8 wt% to prepare a green ink. Then, the polymer light-emitting material 2 that emits blue light was mixed with an organic solvent so that the concentration thereof was 0.8 wt% to prepare a blue ink. Each of these red, green and blue inks was applied in a predetermined recess using an inkjet device (Litrex142P manufactured by ULVAC). Since the ink is repelled by the top surface of the partition wall having a large contact angle with the ink, the ink is prevented from overflowing to the adjacent region through this top surface and is accommodated in the recess. On the other hand, the ink accommodated in the concave portion was filled so as to be sucked into a tapered portion where the first electrode and the partition wall were in contact with each other by capillary action, and spread uniformly in the concave portion. The substrate was baked at 130 ° C. to form a light-emitting layer (film thickness 60 nm) having a uniform thickness (see FIG. 4 (3)). As the polymer light emitting material, for example, a light emitting layer may be formed using a material made by Summation.

Next, a Ca layer (20 nm) and an Al layer (1.2 μm) were sequentially laminated on the light emitting layer by a vacuum deposition method to form a second electrode (cathode). Then, the sealing substrate was bonded together, the organic EL element was sealed, and the display apparatus was produced.

By forming an Al layer having a film thickness of 1.2 μm, it was possible to form a second electrode (cathode) continuous over all organic EL elements. It was confirmed that the produced display device emitted light uniformly in the entire light emitting region provided with the organic EL element. Further, it was confirmed that light was emitted uniformly for each organic EL element in the organic EL element.

(Comparative Example 1)
A display device was produced in the same manner as in Example 1 except that the thickness of the Al layer was changed. In Comparative Example 1, as described in Patent Document 1, an Al layer having a thickness of 150 nm was stacked by a vacuum deposition method. Since the formed second electrode (cathode) was cut at the end of the partition wall, the second electrode continuous across the plurality of organic EL elements was not formed. Therefore, it was not possible to drive each organic EL element to emit light.

(Reference Example 1)
A display device was produced in the same manner as in Example 1 except that the liquid repellent material was not added to the solution used for forming the partition walls. That is, instead of using the photosensitive resin solution containing the liquid repellent material, only the negative photosensitive resin solution (ZPN2464 manufactured by Nippon Zeon Co., Ltd.) was used to form the partition walls. When ink was supplied to the recess using an inkjet device (Litlex142P manufactured by ULVAC) in the same manner as in Example 1, the ink spreads on the top surface of the partition wall and continued to the top surface of the partition wall with the ink supplied to the adjacent region. That was confirmed in part.

Claims

A support substrate;
A partition that defines a predetermined section on the support substrate;
A plurality of organic electroluminescence elements respectively provided in the compartments defined by the partition walls, wherein each organic electroluminescence element includes a first electrode, an organic electroluminescence layer, and a second electrode in this order from the support substrate side. A plurality of organic electroluminescent elements, which are laminated by
The partition has a shape that becomes wider as it is separated from the support substrate,
The second electrode is formed over the partition interposed between adjacent organic electroluminescent elements, is continuous over the plurality of organic electroluminescent elements, and the film thickness of the second electrode is: A display device, which is thicker than a distance between a top surface of the partition wall and an interface between the second electrode and the organic electroluminescence layer in a thickness direction of a support substrate.
The display device according to claim 1, wherein the side wall of the partition wall is lyophilic compared to the top surface.
A support substrate, a partition wall defining a partition set in advance on the support substrate, and a plurality of organic electroluminescence elements respectively provided in the partition defined by the partition wall, each organic electroluminescence element being A method of manufacturing a display device including a plurality of organic electroluminescence elements configured by laminating a first electrode, an organic electroluminescence layer, and a second electrode in this order from the support substrate side,
Preparing the support substrate on which the first electrode is formed;
Forming the partition having a shape that becomes wider as it is separated from the support substrate;
Forming the organic electroluminescence layer in each of the compartments defined by the partition;
Forming the second electrode extending across the plurality of organic electroluminescence elements across the partition interposed between adjacent organic electroluminescence elements, the top surface of the partition; and the first Forming the second electrode having a thickness greater than the distance between the two electrodes and the interface of the organic electroluminescence layer in the thickness direction of the support substrate;
A method for manufacturing a display device, comprising:
The step of forming the partition wall is formed by applying an ink containing a photosensitive resin on the support substrate to form a partition wall forming film, exposing a predetermined portion of the partition wall forming film, and further developing. The manufacturing method of the display apparatus of Claim 3.
The step of forming the organic electroluminescence layer is obtained by supplying ink containing a material for forming the organic electroluminescence layer to each of the compartments defined by the partition walls, and solidifying the ink. Item 4. A method for manufacturing a display device according to Item 3.
The method for manufacturing a display device according to claim 3, wherein in the step of forming the partition wall, a partition wall whose side surface is lyophilic compared to the top surface thereof is formed.
The method for manufacturing a display device according to claim 4, wherein the ink containing the photosensitive resin contains a liquid repellent material.