WO2013035570A1

WO2013035570A1 - Method of manufacturing display device

Info

Publication number: WO2013035570A1
Application number: PCT/JP2012/071583
Authority: WO
Inventors: 合田　匡志
Original assignee: 住友化学株式会社
Priority date: 2011-09-05
Filing date: 2012-08-27
Publication date: 2013-03-14
Also published as: TW201320428A; JP2013054923A

Abstract

The purpose of the present invention is to provide a light-emitting device, and a manufacturing method thereof, capable of suppressing degradation of light emission properties of organic electroluminescence elements during manufacture of display devices by the nozzle printing method. This display device is provided with: a support substrate; multiple organic electroluminescence elements arranged on the support substrate with prescribed spaces in a first direction and in a second direction intersecting the first direction; an insulation film which is provided on the support substrate, has openings in positions corresponding to the organic electroluminescence elements, and individually defines each organic electroluminescence element by said opening; and a separating wall comprising multiple separating wall members provided on the insulation film, said separating wall members extending in the first direction and arranged between the organic electroluminescence elements adjacent in the second direction, wherein the center position in the second direction of each separating wall member is arranged to one side in the second direction, shifted from the center between openings that are adjacent in the second direction.

Description

Manufacturing method of display device

There are various types of display devices. One example is a display device using an organic electroluminescence element (hereinafter also referred to as “organic EL element”) as a light source of a pixel. This display device is arranged at equal intervals along the first direction X between the support substrate, the partition wall 17 composed of a plurality of partition wall members 20 extending in the first direction, and the partition wall member 20. A plurality of organic EL elements are included (see FIG. 4).

The organic EL element is configured by laminating the first electrode 12, one or more functional layers, and the second electrode in this order from the support substrate side.

The functional layer can be formed by a coating method. For example, the functional layer can be formed by supplying ink containing a material for the functional layer to the concave portion between the partition wall member 20 and the partition wall member 20 and further solidifying the ink. For example, the ink is supplied by a nozzle printing method. After the functional layer is formed by the nozzle printing method, a plurality of organic EL elements can be formed on the support substrate by further forming the upper electrode by a predetermined method (see, for example, Patent Document 1).

JP 2008-218250 A

FIG. 4 is a plan view schematically showing a part of the display device, and FIG. 5 is a cross-sectional view of the display device.

In FIG. 4, the arrows schematically show the path of the nozzle 4 of the nozzle printing apparatus. Thus, in the nozzle printing method, ink is applied with a single stroke. In such a system, no matter how the operation of the nozzle printing apparatus is set, as shown in FIG. 5, the present inventors have shown that the shape of the functional layer after drying may not be symmetrical between the partition members. Found. The organic EL element having the functional layer formed asymmetrically between the partition members may have lower light emission characteristics than the organic EL element having the functional layer formed symmetrically.

Therefore, an object of the present invention is to provide a light emitting device capable of suppressing a decrease in light emission characteristics of an organic EL element and a method for manufacturing the same when producing a display device by a nozzle printing method.

The present invention provides the following [1] and [2].
[1] a support substrate;
On the support substrate, a plurality of organic EL elements disposed at predetermined intervals in a first direction and a second direction intersecting the first direction,
An insulating film provided on the support substrate, having openings at positions corresponding to the plurality of organic EL elements, and individually defining each organic EL element through the openings;
A partition comprising a plurality of partition members provided on the insulating film, each partition member being disposed between organic EL elements adjacent in the second direction and extending in the first direction A display device comprising:
Each partition member is arranged such that the center position of the partition member in the second direction is shifted from the center of the width between the openings adjacent in the second direction in one of the second directions. .

[2] A support substrate, a plurality of organic EL elements arranged on the support substrate at predetermined intervals in a first direction and a second direction intersecting the first direction, and the support substrate A partition wall comprising an insulating film having openings at positions corresponding to the plurality of organic EL elements, and a plurality of partition wall members provided on the insulation film, each partition member being the second A method of manufacturing a display device including a partition wall disposed between organic EL elements adjacent to each other in a direction and extending in a first direction,
providing a support substrate provided with i) pixel electrodes of the plurality of organic EL elements, and ii) an insulating film having an opening at a position corresponding to the pixel electrodes;
Providing a partition by forming a plurality of partition members on the insulating film; and
Forming a predetermined functional layer of the organic EL element on the pixel electrode by supplying a predetermined ink to the region between the partition members by a nozzle printing method and solidifying the ink;
Forming an upper electrode on the functional layer,
In the step of providing the partition wall, each partition member shifts the center position of the partition member in the second direction to one of the second directions from the center of the width between the openings adjacent to the second direction. A method for manufacturing a display device.

According to the present invention, it is possible to provide a light emitting device capable of suppressing a decrease in the light emission characteristics of the organic EL element and a method for manufacturing the same when producing a display device by a nozzle printing method.

FIG. 1 is a plan view schematically showing a light emitting device 21 according to an embodiment of the present invention. FIG. 2 is a sectional view schematically showing the light emitting device 21 in an enlarged manner. FIG. 3 is a diagram exaggerating the shape of the functional layer and the like with respect to the cross section of the light emitting device 21. FIG. 4 is a diagram schematically showing an operation when applying ink by the nozzle printing method. FIG. 5 is a diagram showing exaggerated shapes of functional layers and the like in the cross section of the light emitting device 21.

The display device of the present invention includes a support substrate, and a plurality of organic EL elements arranged on the support substrate in a first direction and in a second direction intersecting the first direction with a predetermined interval, respectively. And an insulating film provided on the support substrate and having openings at positions corresponding to the plurality of organic EL elements, and each organic EL element individually defined by the openings, and a plurality of the insulating films provided on the insulating film Each of the partition members is provided between the organic EL elements adjacent to each other in the second direction and extends in the first direction. The center position of the partition member in the second direction is shifted from the center of the width between the openings adjacent in the second direction in one of the second directions.

The display device mainly includes an active matrix drive type device and a passive matrix drive type device. Although the present invention may be applied to both types of display devices, in this embodiment, a light emitting device applied to an active matrix drive type display device will be described as an example.

<Configuration of light emitting device>
First, the structure of the light emitting device will be described. FIG. 1 is a plan view schematically showing the light emitting device 21 of this embodiment, and FIG. 2 is a cross-sectional view schematically showing the light emitting device 21 in an enlarged manner. The light emitting device 21 mainly includes a support substrate 11 and a plurality of organic EL elements 22 provided on the support substrate.

In the present embodiment, the plurality of organic EL elements 22 are arranged in a matrix on the support substrate 11 with predetermined intervals in the first direction X and the second direction Y intersecting with the first direction X, respectively. Be placed. In the present embodiment, the organic EL elements 22 are arranged at equal intervals in the first direction X, and are also arranged at equal intervals in the second direction Y.

In the present embodiment, the first direction X and the second direction Y are perpendicular to the thickness direction Z of the support substrate 11. In the present embodiment, the first direction X and the second direction Y are perpendicular to each other. Hereinafter, the thickness direction Z of the support substrate 11 may be simply referred to as the thickness direction Z.

An insulating film 15 that individually defines each organic EL element 22 is provided on the support substrate.
The insulating film 15 has openings at positions corresponding to the plurality of organic EL elements. Each organic EL element 22 is provided at a position corresponding to the opening of the insulating film 15 when viewed from one side in the thickness direction Z (hereinafter also referred to as “plan view”). As will be described later, the functional layer constituting the organic EL element is formed to be continuous with the organic EL element 22 adjacent in the first direction X, and is physically continuous. However, the organic EL element 22 adjacent in the first direction X is electrically insulated by the insulating film 15.

Since the openings of the insulating film 15 are formed at positions corresponding to the organic EL elements 22, they are arranged in a matrix like the organic EL elements 22. Thus, the insulating film 15 has a matrix-like opening. In other words, the insulating film 15 is formed in a lattice shape in plan view. The opening of the insulating film 15 is formed so as to substantially coincide with a pixel electrode 12 to be described later in plan view, and is formed in, for example, a substantially rectangular shape, a substantially circular shape, a substantially elliptical shape, or the like. The lattice-like insulating film 15 is mainly formed in a region excluding the pixel electrode 12 in plan view. A part of the lattice-like insulating film 15 is formed to cover the periphery of the pixel electrode 12.

In this embodiment, the partition wall 17 composed of a plurality of partition wall members 20 is provided on the insulating film 15. Each partition member 20 is disposed between organic EL elements adjacent in the second direction Y. Each partition member 20 also extends in the first direction X. As described above, in this embodiment, the so-called stripe-shaped partition wall 17 is provided on the insulating film 15.

The organic EL element 22 is provided in a section defined by the partition wall 17. In the present embodiment, the plurality of organic EL elements 22 are provided in a region between the partition members 20 adjacent to each other in the second direction Y (that is, the recess 18), and in the region between the partition members 20 in the first direction X. They are arranged at a predetermined interval. The organic EL elements 22 do not have to be physically separated from each other, and may be electrically insulated so that they can be individually driven. Therefore, some layers (electrodes and functional layers) constituting the organic EL element may be physically connected to other organic EL elements.

In the present embodiment, the organic EL element 22 is configured by arranging the first electrode 12, the functional layers 13 and 14, and the second electrode 16 in this order from the support substrate 11 side. In the present specification, the first electrode 12 is referred to as a pixel electrode 12, and the second electrode 16 is referred to as an upper electrode 16.

The pixel electrode 12 and the upper electrode 16 constitute a pair of electrodes composed of an anode and a cathode. That is, one of the pixel electrode 12 and the upper electrode 16 is provided as an anode, and the other is provided as a cathode. The pixel electrode 12 is disposed closer to the support substrate 11, and the upper electrode 16 is disposed farther from the support substrate 11 than the pixel electrode 12.

The organic EL element 22 includes one or more functional layers. In this specification, the functional layer means all layers sandwiched between the pixel electrode 12 and the upper electrode 16. The organic EL element 22 includes at least one light emitting layer as a functional layer. In addition, a predetermined layer is provided between the electrodes as needed without being limited to the light emitting layer. Examples of the functional layer provided between the anode and the light emitting layer include a hole injection layer, a hole transport layer, and an electron block layer. Examples of the functional layer provided between the light emitting layer and the cathode include a hole blocking layer, an electron transporting layer, and an electron injecting layer.

The organic EL element 22 of this embodiment includes a hole injection layer 13 as a functional layer between the pixel electrode 12 and the light emitting layer 14.

Hereinafter, as an embodiment of the present invention, a pixel electrode 12 that functions as an anode, a hole injection layer 13, a light emitting layer 14, and an upper electrode 16 that functions as a cathode are included in this order from the support substrate 11 side. The organic EL element 22 will be described.

The light-emitting device 21 of the present embodiment is an active matrix type device, and the pixel electrode 12 is individually provided for each organic EL element 22 so that each organic EL element 22 can be driven individually. That is, the same number of pixel electrodes 12 as the number of organic EL elements 22 are provided on the support substrate 11. For example, the pixel electrode 12 has a thin film shape and is formed in a substantially rectangular shape in plan view. The plurality of pixel electrodes 12 are provided in a matrix form on the support substrate 11 corresponding to the positions where each organic EL element is provided. The plurality of pixel electrodes 12 are arranged at predetermined intervals in the first direction X and at predetermined intervals in the second direction Y. The pixel electrode 12 is provided in a region between the partition members 20 adjacent in the second direction Y in a plan view, and is disposed between the partition members 20 with a predetermined interval in the first direction X.

As described above, the lattice-like insulating film 15 is mainly formed in a region excluding the pixel electrode 12 in a plan view, and a part thereof is formed so as to cover the periphery of the pixel electrode 12. That is, an opening is formed in the insulating film 15 at a position corresponding to the pixel electrode 12, and the surface of the pixel electrode 12 is exposed from the insulating film 15 through this opening.

The hole injection layer 13 extends in the first direction X in the region between the partition members 20. That is, the hole injection layer 13 is formed in a strip shape in the recess 18 defined by the partition wall member 20 adjacent in the second direction Y, and continuously over the organic EL elements 22 adjacent in the first direction X. Is formed.

The light emitting layer 14 extends in the first direction X in the region between the partition members 20. That is, the light emitting layer 14 is formed in a strip shape in the recess 18 defined by the partition member 20 adjacent in the second direction Y, and is continuously formed over the organic EL elements adjacent in the first direction X. Yes. The band-shaped light emitting layer 14 is laminated on the band-shaped hole injection layer 13.

Although the present invention can be applied to a monochrome display device, a color display device will be described as an example in this embodiment. In the case of a color display device, three types of organic EL elements that emit light of any one of red, green, and blue are provided on the support substrate 11. The color display device can be realized, for example, by repeatedly arranging the following rows (I), (II), and (III) in the second direction Y in this order.

(I) A row in which a plurality of organic EL elements 22R emitting red light are arranged in the first direction X with a predetermined interval.
(II) A row in which a plurality of organic EL elements 22G that emit green light are arranged in the first direction X at a predetermined interval.
(III) A row in which a plurality of organic EL elements 22B emitting blue light are arranged in the first direction X with a predetermined interval.

Thus, when three types of organic EL elements having different emission colors are formed, a light emitting layer having a different emission color is usually provided for each type of element. In the present embodiment, the following rows (i), (ii), and (iii) are repeatedly arranged in the second direction Y in this order.

(I) A row provided with a light emitting layer 14R that emits red light.
(Ii) A row in which the light emitting layer 14G emitting green light is provided.
(Iii) A row in which the light emitting layer 14B emitting blue light is provided.

In this case, three types of strip-shaped

light emitting layers

14R, 14G, and 14B extending in the first direction X are sequentially stacked on the hole injection layer 13 with two rows in the second direction Y, respectively. The

The upper electrode 16 is provided on the light emitting layer 14. In the present embodiment, the upper electrode 16 is continuously formed across the plurality of organic EL elements 22 and provided as a common electrode for the plurality of organic EL elements. The upper electrode 16 is formed not only on the light emitting layer 14 but also on the partition wall 17, and is formed on one surface so that the electrode on the light emitting layer 14 and the electrode on the partition wall 17 are connected.

FIG. 3 is a diagram showing exaggerated shapes of functional layers and the like with respect to the cross section of the light emitting device 21. In FIG. 3, the pixel electrode 12 and the upper electrode 16 are not shown for easy understanding.

Each partition member 20 is arranged such that the center position of the partition member 20 in the second direction Y is shifted to one of the second directions from the center of the width between the openings adjacent to the second direction Y. Yes. That is, the insulating film 15 is formed between the openings adjacent in the second direction Y, and the center position of the partition member 20 in the second direction Y is in the center of the second direction Y of the insulating film 15. Rather than aligning, the partition member 20 is arranged along one side of the insulating film 15 in the second direction Y. Referring to FIG. 3, the trapezoidal partition wall member 20 is arranged on the rectangular insulating film 15 so as to be shifted from the center in the second direction Y to the left.

The shift width M in the second direction Y between the center position of the partition wall member 20 in the second direction Y and the center position of the width between the openings adjacent to the second direction Y depends on the shape of the functional layer. You may set suitably. In one embodiment, when the distance (width) between openings adjacent to each other in the second direction Y is W, it is preferable that the relationship of the following formula (1) is satisfied.

c <M / W ≦ b (1)
In the above formula (1), b is preferably 0.2, more preferably 0.1. In the above formula (1), c is preferably 0.02, and more preferably 0.05.

The functional layer is formed asymmetrically between the partition members 20 as described above. In the present invention, it is preferable that the shift width M is set so that the position where the thickness of the functional layer is minimized coincides with the center of the opening in the second direction. In addition, when a certain position in the width in the second direction of the opening is represented by a distance from one end thereof and a distance to the other end is represented by X, a position A at which the thickness of the functional layer is minimized is expressed by the following equation (2) It is preferable to satisfy the relationship.

| A / X-0.5 | ≦ a (2)
In the above formula (2), a is preferably 0.2, and more preferably 0.1.

Further, in the predetermined concave portion 18, when the section H1 between the one partition wall member 20 in the second direction Y and the surface of the functional layer is compared with the section H2 between the other partition wall member 20 and the surface of the functional layer, It is preferable to arrange the partition wall member 20 so that the center position of the partition wall member 20 in the second direction Y is shifted to the higher section. Symbols H1 and H2 represent heights from the support substrate 11, respectively. By arranging the partition member 20 in this way, for example, the relationship of the above formula (2) can be satisfied.

For example, referring to FIG. 3, since the left segment H1 is higher than the right segment H2, the center position of the partition member 20 in the second direction Y is the width between the openings adjacent to the second direction Y. It is preferable to shift to the left rather than the center position.

The shift width M in the second direction Y between the center position of the partition wall member 20 in the second direction Y and the center position of the width between the openings adjacent to the second direction Y and the direction of the shift are as follows. It can be determined according to the method. That is, the partition member 20 is actually formed on the support substrate 11 as a prototype, and a thin film is formed in a region between the partition members 20. Then, the relationship between H1 and H2 can be grasped, and based on this relationship, the shift width M and the direction in which it can be shifted can be determined.

By arranging the partition member 20 as described above, the functional layer can be formed substantially symmetrically in the second direction Y within the opening. Accordingly, an organic EL element that emits light substantially uniformly in the opening in a plan view can be realized, and the light emission characteristics of the organic EL element can be improved.

<Method for manufacturing light emitting device>
Next, a method for manufacturing the light emitting device will be described.

The manufacturing method of the light-emitting device of the present invention includes a support substrate and a plurality of the substrate arranged at predetermined intervals in the first direction and the second direction intersecting the first direction on the support substrate. A partition comprising an organic EL element, an insulating film having openings at positions corresponding to the plurality of organic EL elements, and a plurality of partition members provided on the insulating film, each partition member being the second partition A display device comprising a partition wall disposed between organic EL elements adjacent to each other in a direction extending in a first direction, i) pixel electrodes of the plurality of organic EL elements, and ii) A step of providing a support substrate provided with an insulating film having an opening at a position corresponding to the pixel electrode, a step of providing a partition by forming a plurality of partition members on the insulating film, and the partition member Nozzle print in the area between A predetermined ink layer is supplied by solidification and solidified to form a predetermined functional layer of the organic EL element on the pixel electrode, and an upper electrode is formed on the functional layer. In the step of providing the partition, each partition member has a center position of the partition member in the second direction, and a center of the width between the openings adjacent to the second direction is set to one of the second directions. The present invention relates to a manufacturing method of a display device which is formed by shifting.

(Process for preparing support substrate)
In this step, a support substrate 11 is prepared in which i) pixel electrodes 12 of a plurality of organic EL elements and ii) an insulating film 15 having openings at positions corresponding to the pixel electrodes 12 are provided thereon. 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 11. For example, a substrate on which a TFT (Thin Film Transistor), a capacitor, and the like are formed in advance may be used as the support substrate. The support substrate 11 on which the pixel electrode 12 and the insulating film 15 are provided may be prepared by forming the pixel electrode 12 in this step as follows. Alternatively, the support substrate 11 may be prepared by obtaining from the market a support substrate 11 on which the pixel electrode 12 and the insulating film 15 are previously provided.

First, a plurality of pixel electrodes 12 are formed on a support substrate 11 in a matrix. The pixel electrode 12 is formed, for example, by forming a conductive thin film on one surface of the support substrate 11 and patterning it in a matrix by a photolithography method. Further, for example, a mask having an opening at a predetermined portion is disposed on the support substrate 11, and the pixel electrode 12 is patterned by selectively depositing a conductive material on the predetermined portion on the support substrate 11 through the mask. May be. The material of the pixel electrode 12 will be described later.

Next, a lattice-like insulating film 15 is formed on the support substrate 11. The insulating film 15 is made of an organic material or an inorganic material. Examples of the organic material constituting the insulating film 15 include resins such as acrylic resin, phenol resin, and polyimide resin. As the inorganic material which constitutes the insulating film 15, for example, and the like SiO _x or SiN _x.

When forming the insulating film 15 made of an inorganic material, for example, a thin film made of an inorganic material is formed on one surface by a plasma CVD method, a sputtering method, or the like, and then a predetermined portion is removed to form the lattice-shaped insulating film 15. The predetermined part is removed by, for example, a photolithography method.

When forming the insulating film 15 made of an organic material, first, for example, a positive or negative photosensitive resin is applied to one surface, and a predetermined portion is exposed and developed. Further, by curing this, a lattice-like insulating film 15 is formed. Note that a photoresist may be used as the photosensitive resin.

Next, the partition wall 17 is formed. That is, a plurality of partition members 20 are formed on the insulating film 15 to provide the partition walls 17. In this step, each partition member is formed by shifting the center position of the partition member 20 in the second direction to one of the second directions from the center of the width between the openings adjacent in the second direction. .

The partition wall 17 can be formed in a stripe shape in the same manner as the method of forming the insulating film 15 using, for example, the material exemplified as the material of the insulating film 15.

Note that the partition wall 17 is preferably made of an organic material. In order to retain the ink supplied to the recess 18 surrounded by the partition wall 17 in the recess 18, the partition wall preferably exhibits liquid repellency. In general, an organic material has a liquid repellency with respect to ink rather than an inorganic material. Therefore, by forming a partition wall with an organic material, the ability to retain ink in the recess 18 can be enhanced.

The shape of the partition wall 17 and the arrangement thereof may be appropriately set according to the specifications of the display device such as the number of pixels and resolution, the ease of manufacturing, and the like. For example, the width L1 of the partition member 20 in the second direction Y is about 5 μm to 50 μm, the height L2 of the partition member 20 in the thickness direction Z is about 0.5 μm to 5 μm, and the second direction of the recess 18 The width L3 of Y is about 10 μm to 200 μm. The width of the pixel electrode 12 in the first direction X and the second direction Y is about 10 μm to 400 μm, respectively.

(Process for forming functional layer)
In this step, a predetermined functional layer of the organic EL element is formed on the pixel electrode by supplying a predetermined ink to the region between the partition members by a nozzle printing method and solidifying the ink. The predetermined ink means an ink containing a material that becomes a functional layer (in this embodiment, a hole injection layer and a light emitting layer). In this step, when a plurality of functional layers are provided, at least one layer is formed by a nozzle printing method.

In this embodiment, in order to form the hole injection layer 13 common to all organic EL elements, an ink containing a material that becomes the hole injection layer 13 only in the region between the partition members 20 (hereinafter referred to as “hole injection layer”). The ink for the hole injection layer may be supplied to the entire surface. The ink for the hole injection layer may be provided in any way for this. For example, the ink for the hole injection layer can be supplied by a coating method such as a spin coating method, a slit coating method, an ink jet printing method, a nozzle printing method, a relief printing method, and an intaglio printing method. As a method for supplying the hole injection layer ink, a method capable of supplying the hole injection layer ink uniformly in a short time is preferable. From such a viewpoint, a spin coating method, a slit coating method or a nozzle printing method is preferable. When the hole injection layer ink is applied to the entire surface, the hole injection layer may be formed even on the partition wall depending on the properties of the partition wall surface. In order to avoid this, it may be preferable to supply the hole injection layer ink only to the recess 18. In this case, the hole injection layer ink is supplied by a coating method that can selectively supply the hole injection layer ink only to the recesses 18. In the present embodiment, the hole injection layer ink is supplied by a nozzle printing method as a coating method capable of selectively supplying the hole injection layer ink.

Hereinafter, this process will be described with reference to FIG. FIG. 4 is a diagram schematically showing the operation when applying ink by the nozzle printing method. Note that FIG. 4 uses the same figure as cited in the problem section, but the arrangement of the partition members is different between the display device of the present embodiment and the conventional display apparatus described in the problem section.

In the nozzle printing method, the ink for the hole injection layer is supplied to each row (each concave portion 18) with a single stroke. That is, the nozzle 4 is reciprocated in the first direction X while the liquid columnar hole injection layer ink is ejected from the nozzle disposed above the support substrate 11. Then, when the nozzle 4 is turned back and forth, the support substrate is moved by a predetermined distance in the second direction Y, whereby the hole injection layer ink is supplied to each row. For example, when the reciprocating movement of the nozzle 4 is turned back, the hole injection layer ink can be supplied to all rows by moving the support substrate by one row in the second direction Y.

More specifically, by repeating the following steps (1) to (4) in this order while discharging the liquid columnar hole injection layer ink from the nozzles 4, the region between all the partition members 20 ( The hole injection layer ink can be supplied to the recesses 18).
(1) A step of moving the nozzle 4 from one end to the other end in the first direction X.
(2) A step of moving the support substrate 11 in one direction in the second direction Y by one line.
(3) A step of moving the nozzle 4 from the other end in the first direction X to one end.
(4) A step of moving the support substrate by one line in one of the second directions Y.

By supplying the ink for hole injection layer by the nozzle printing method as described above, a thin film made of the ink for hole injection layer is formed.

As described above, in this embodiment, each partition member has the center position in the second direction of the partition member, and the center of the width between the openings adjacent in the second direction is one of the second directions. It is arranged to shift to. By arranging the partition member in this way, even if ink is applied by the nozzle printing method, the hole injection layer is formed substantially symmetrically in the second direction Y in the opening as shown in FIG. Can do.

(Step of forming the light emitting layer)
Next, a light emitting layer is formed. As described above, when producing a color display device, it is necessary to produce three types of organic EL elements. Therefore, it is necessary to coat the material of the light emitting layer for each row. For example, when three types of light emitting layers are formed for each row, red ink containing a material that emits red light, green ink containing a material that emits green light, and blue ink containing a material that emits blue light, respectively. It is necessary to apply in the direction Y of 2 with an interval of 2 rows. By sequentially applying the red ink, the green ink, and the blue ink to predetermined rows, each light emitting layer can be coated and formed.

As a method for sequentially applying the red ink, the green ink, and the blue ink to a predetermined line, any method may be used as long as the ink can be selectively supplied to the region between the partition members. For example, ink can be supplied by an ink jet printing method, a nozzle printing method, a relief printing method, an intaglio printing method, or the like. As a method for supplying ink, a method capable of supplying ink uniformly in a short time is preferable. From such a viewpoint, the nozzle printing method is preferable. In the present embodiment, ink is supplied by a nozzle printing method as in the method for forming the hole injection layer described above.

More specifically, the following steps (1) to (4) are repeated in this order while the liquid columnar red ink is being discharged from the nozzle 4, so that two rows are spaced in the second direction Y. Red ink can be supplied to the region between the partition members 20 (recessed portion 18).
(1) A step of moving the nozzle 4 from one end to the other end in the first direction X.
(2) A step of moving the support substrate 11 in one direction in the second direction Y by three rows.
(3) A step of moving the nozzle 4 from the other end in the first direction X to one end.
(4) A step of moving the support substrate in one direction in the second direction Y by three rows.

By supplying green ink and blue ink in the same manner as the red ink described above, green ink and blue ink are respectively provided in the region (concave portion 18) between the partition members 20 with an interval of two rows in the second direction Y. Can be supplied.

The luminescent materials used for red ink, green ink, and blue ink will be described later. Each ink may contain a polymerizable compound that can be polymerized by applying energy. As the ink, a red ink, a green ink, or a blue ink containing a light emitting material having a polymerizable group that can be polymerized by applying energy as a polymerizable compound may be used. Moreover, you may use the red ink, green ink, and blue ink containing the luminescent material which does not superpose itself, and the polymeric compound which has the polymerizable group which can superpose | polymerize in addition to this luminescent material.

Examples of the polymerizable group include a vinyl group, an ethynyl group, a butenyl group, an acryloyl group, an acryloylamino group, a methacryloyl group, a methacryloylamino group, a vinyloxy group, a vinylamino group, a silanol group, a cyclopropyl group, a cyclobutyl group, and an epoxy group. Oxetanyl group, diketenyl group, epithio group, lactonyl group, lactamnyl group and the like.

Examples of the polymerizable compound include a PDA (N, N′-tetraphenyl-1,4-phenylenediamine) derivative having a polymerizable group and a TPD (N, N′-bis (3- Methylphenyl) -N, N′-bis (phenyl) -benzidine) derivative, NPD (N, N′-bis (naphthalen-1-yl) -N, N′-bis (phenyl)-) having a polymerizable group Benzidine) derivatives, triphenylamine acrylate, triphenylenediamine acrylate, phenylene acrylate, bisphenoxyethanol full orange acrylate (trade name BPEF-A manufactured by Osaka Gas Chemical Company), dipentaerythritol hexaacrylate (KAYARD DPHA manufactured by Nippon Kayaku), Trispentaerythritol octaacrylate (Guangei Chemical) 1 1,4-butanediol diacrylate (manufactured by Alfa Aesar Co.), ARON (OXT121; manufactured by Toagosei Co. crosslinking agent) can be mentioned, such as, phenyl fluorene acrylate is preferable among these.

As described above, in this embodiment, each partition member has the center position in the second direction of the partition member, and the center of the width between the openings adjacent in the second direction is one of the second directions. It is arranged to shift to. By arranging the partition member in this way, even when ink is applied by the nozzle printing method, the light emitting layer can be formed substantially symmetrically in the second direction Y as shown in FIG. .

After forming the light emitting layer, a predetermined organic layer or inorganic layer is formed by a predetermined method as necessary. These may be formed using a predetermined coating method such as a printing method, an ink jet method, a nozzle printing method, or a predetermined dry method.

(Process of forming the upper electrode)
Next, an upper electrode is formed. As described above, in this embodiment, the upper electrode is formed on the entire surface of the support substrate. Thereby, a plurality of organic EL elements can be formed on the substrate.

As described above, in this embodiment, each partition member has the center position in the second direction of the partition member, and the center of the width between the openings adjacent in the second direction is the second direction. They are shifted to one side. By disposing the partition wall member 20 in this manner, the hole injection layer and the light emitting layer can be formed substantially symmetrically in the second direction Y within the opening. Accordingly, an organic EL element that emits light substantially uniformly in the opening in a plan view can be realized, and the light emission characteristics of the organic EL element can be improved.

<Configuration of organic EL element>
As described above, the organic EL element can have various layer configurations. Hereinafter, the layer structure of the organic EL element, the configuration of each layer, and the method of forming each layer will be described in more detail.

As described above, the organic EL element includes a pair of electrodes (pixel electrode and upper electrode) composed of an anode and a cathode, and one or more functional layers provided between the electrodes. As a layer, at least one light emitting layer is provided. The organic EL element may include a layer containing an inorganic substance and an organic substance, an inorganic layer, and the like. The organic substance constituting the organic layer may be a low molecular compound or a high molecular compound, or a mixture of a low molecular compound and a high molecular compound. The organic layer preferably contains a polymer compound, and preferably contains a polymer compound having a polystyrene-equivalent number average molecular weight of 10 ³ to 10 ⁸ .

Examples of the functional layer provided between the cathode and the light emitting layer include an electron injection layer, an electron transport layer, and a hole blocking layer. When both the electron injection layer and the electron transport layer are provided between the cathode and the light emitting layer, the layer close to the cathode is called an electron injection layer, and the layer close to the light emitting layer is called an electron transport layer. Examples of the functional layer provided between the anode and the light emitting layer include a hole injection layer, a hole transport layer, and an electron block layer. When both the hole injection layer and the hole transport layer are provided, a layer close to the anode is referred to as a hole injection layer, and a layer close to the light emitting layer is referred to as a hole transport 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) The same shall apply hereinafter.)

The organic EL element of the present embodiment may have two or more light emitting layers. In any one of the layer configurations of a) to p) above, when the laminate sandwiched between the anode and the cathode is referred to as “structural unit A”, the configuration of the organic EL device having two light emitting layers is as follows. For example, the layer configuration shown in the following q) can be given. Note that the two (structural unit A) layer structures may be the same or different.
q) Anode / (structural unit A) / charge generating layer / (structural unit A) / cathode If “(structural unit A) / charge generating layer” is “structural unit B”, it has three or more light emitting layers. As a structure of an organic EL element, the layer structure shown to the following r) can be mentioned, for example.
r) anode / (structural unit B) x / (structural unit A) / cathode The symbol “x” represents an integer of 2 or more, and (structural unit B) x is a stack in which the structural unit B is stacked in x stages. Represents the body. A plurality of (structural units B) may have the same or different layer structure.

Here, the charge generation layer is a layer that generates holes and electrons by applying an electric field. Examples of the charge generation layer may include a thin film made of vanadium oxide, indium tin oxide (abbreviated as ITO), molybdenum oxide, or the like.

The organic EL element may be provided on the support substrate with the anode disposed closer to the support substrate than the cathode, or may be provided on the support substrate with the cathode disposed closer to the support substrate than the anode. For example, in the above a) to r), each layer may be laminated on the support substrate in order from the right side to constitute an organic EL element, or each layer may be laminated on the support substrate in order from the left side to constitute an organic EL element. May be. The order of the layers to be laminated, the number of layers, and the thickness of each layer may be set as appropriate in consideration of light emission efficiency and element lifetime.

Next, the material and forming method of each layer constituting the organic EL element will be described more specifically.

<Anode>
In the case of an organic EL element configured to emit light emitted from the light emitting layer to the outside of the element through the anode, a light transmissive electrode is used for the anode. As the light transmissive electrode, for example, a thin film of metal oxide, metal sulfide, metal, or the like may be used. Among these, a thin film having high electrical conductivity and high light transmittance is preferably used. Specifically, thin films made of indium oxide, zinc oxide, tin oxide, ITO, indium zinc oxide (abbreviated as IZO), gold, platinum, silver, copper, and the like are 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, as the anode, an organic transparent conductive film such as polyaniline or a derivative thereof, polythiophene or a derivative thereof may be used.

The film thickness of the anode may be appropriately set in consideration of the required characteristics and the simplicity of the film forming process. For example, the thickness is 10 nm to 10 μm, preferably 20 nm to 1 μm, and more preferably 50 nm to 500 nm.

<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, a material having a high reflectivity with respect to visible light is preferable as the cathode material in order to reflect light emitted from the light emitting layer to the anode side by the cathode. For the cathode, for example, an alkali metal, an alkaline earth metal, a transition metal, a Group 13 metal of the periodic table, or the like may be used. Examples of cathode materials include lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, and ytterbium. A metal; two or more alloys of the metals; selected from the group consisting of one or more of the metals and gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, and tin One or more alloys; or graphite or graphite intercalation compounds are used. Examples of alloys include magnesium-silver alloys, magnesium-indium alloys, magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum alloys, lithium-magnesium alloys, lithium-indium alloys, calcium-aluminum alloys, and the like. it can. As the cathode, a transparent conductive electrode made of a conductive metal oxide, a conductive organic material, or the like may be used. Specifically, examples of the conductive metal oxide include indium oxide, zinc oxide, tin oxide, ITO, and IZO. Examples of the conductive organic substance include polyaniline or a derivative thereof, polythiophene or a derivative thereof, and the like. Can be mentioned. The cathode may be composed of a laminate in which two or more layers are laminated. The electron injection layer may be used as a cathode.

The film thickness of the 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. .

Examples of the method for producing the cathode include a vacuum deposition method, a sputtering method, and a laminating method in which a metal thin film is thermocompression bonded.

<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, Examples thereof include amorphous carbon, polyaniline, and polythiophene derivatives.

The thickness of the hole injection layer may be appropriately 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.

<Hole transport layer>
Examples of the hole transport material constituting the hole transport layer include polyvinyl carbazole or a derivative thereof, polysilane or a derivative thereof, a polysiloxane derivative having an aromatic amine in a side chain or a main chain, a pyrazoline derivative, an arylamine derivative, a stilbene. Derivative, 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, or poly (2,5-thienylene vinylene) ) Or a derivative thereof.

The film thickness of the hole transport layer is 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, more preferably 5 nm to 200 nm. .

<Light emitting layer>
The light emitting layer is usually formed of an organic substance that mainly emits fluorescence and / or phosphorescence, or an organic substance and a dopant that assists the organic substance. The dopant is added, for example, in order to improve the luminous efficiency and change the emission wavelength. The organic substance constituting the light emitting layer may be a low molecular compound or a high molecular compound. When forming a light emitting layer by the apply | coating method, it is preferable that a light emitting layer contains a high molecular compound. The number average molecular weight in terms of polystyrene of the polymer compound constituting the light emitting layer is, 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, coumarin derivatives, and the like.

(Metal complex materials)
Examples of metal complex materials include rare earth metals (eg, Tb, Eu, Dy, etc.), metals such as Al, Zn, Be, Ir, and Pt as central metals, oxadiazole, thiadiazole, phenylpyridine, phenyl A metal complex having a benzimidazole, quinoline structure, or the like as a ligand can be given. Specifically, for example, a metal complex having light emission from a triplet excited state such as an iridium complex, a platinum complex, an aluminum quinolinol complex, a benzoquinolinol beryllium complex, a benzoxazolyl zinc complex, a benzothiazole zinc complex, an azomethyl zinc complex, A porphyrin zinc complex, a phenanthroline europium complex, etc. can be mentioned.

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

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

<Electron transport layer>
As the electron transporting material constituting the electron transporting layer, known materials can be used. For example, oxadiazole derivatives, anthraquinodimethane or derivatives thereof, benzoquinone or derivatives thereof, naphthoquinone or derivatives thereof, anthraquinones or derivatives thereof, tetra Cyanoanthraquinodimethane or derivatives thereof, fluorenone derivatives, diphenyldicyanoethylene or derivatives thereof, diphenoquinone derivatives, or metal complexes of 8-hydroxyquinoline or derivatives thereof, polyquinoline or derivatives thereof, polyquinoxaline or derivatives thereof, polyfluorene or derivatives thereof And so on.

The thickness of the electron transport layer may be appropriately 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, more preferably 5 nm to 200 nm. It is.

<Electron injection layer>
As a material constituting the electron injection layer, an optimum material may be appropriately selected according to the type of the light emitting layer. For example, one or more of alkali metals, alkaline earth metals, alkali metals, and alkaline earth metals may be selected. Alloys, alkali metal or alkaline earth metal oxides, halides, and carbonates; and mixtures thereof. Examples of alkali metals, alkali metal oxides, halides, and carbonates include lithium, sodium, potassium, rubidium, cesium, lithium oxide, lithium fluoride, sodium oxide, sodium fluoride, potassium oxide, and potassium fluoride. , Rubidium oxide, rubidium fluoride, cesium oxide, cesium fluoride, lithium carbonate, and the like. Examples of alkaline earth metal, alkaline earth metal oxides, halides and carbonates include magnesium, calcium, barium, strontium, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, barium oxide, Examples thereof include barium fluoride, strontium oxide, strontium fluoride, and magnesium carbonate. An electron injection layer may be comprised by the laminated body which laminated | stacked two or more layers, for example, LiF / Ca etc. can be mentioned.

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

In the case where there are a plurality of functional layers that can be formed by a coating method among the functional layers, it is preferable to form all the functional layers by using the coating method. At least one of the plurality of functional layers may be formed by a coating method, and the other functional layers may be formed by a method different from the coating method. Even when a plurality of functional layers are formed by a coating method, the plurality of functional layers may be formed by a coating method with a different specific method. For example, in this embodiment, the hole injection layer and the light emitting layer are formed by a nozzle printing method, but the hole injection layer may be formed by a spin coating method and the light emitting layer may be formed by a nozzle printing method.

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

Further, the functional layer may be formed by a method different from the coating method. For example, the functional layer may be formed by a vacuum deposition method, a sputtering method, a CVD method, a lamination method, or the like.

4 nozzle 11 support substrate 12 pixel electrode 13 hole injection layer 14 light emitting layer 15 insulating film 16 upper electrode 17 partition 18 recess 20 partition member 21 light emitting device 22 organic EL element

Claims

A support substrate;
On the support substrate, a plurality of organic EL elements disposed at predetermined intervals in a first direction and a second direction intersecting the first direction,
An insulating film provided on the support substrate, having an opening at a position corresponding to the plurality of organic electroluminescence elements, and individually defining each organic electroluminescence element by the opening;
A partition wall made of a plurality of partition wall members provided on the insulating film, each partition wall member being disposed between adjacent organic electroluminescence elements in the second direction and extending in the first direction. A display device comprising a partition,
Each partition member is arranged such that the center position of the partition member in the second direction is shifted from the center of the width between the openings adjacent in the second direction in one of the second directions. .
A support substrate, a plurality of organic electroluminescence elements disposed on the support substrate at predetermined intervals in a first direction and a second direction intersecting the first direction, and the support substrate; A partition wall including an insulating film having openings at positions corresponding to the plurality of organic electroluminescence elements, and a plurality of partition wall members provided on the insulating film, each partition member being the second A method of manufacturing a display device including a partition wall, which is disposed between organic electroluminescence elements adjacent in a direction and extends in a first direction,
i) preparing a support substrate provided with pixel electrodes of the plurality of organic electroluminescence elements; and ii) an insulating film having an opening at a position corresponding to the pixel electrodes;
Providing a partition by forming a plurality of partition members on the insulating film; and
Supplying a predetermined ink to the region between the partition members by a nozzle printing method and solidifying the ink to form a predetermined functional layer of the organic electroluminescence element on the pixel electrode;
Forming an upper electrode on the functional layer,
In the step of providing the partition wall, each partition member shifts the center position of the partition member in the second direction to one of the second directions from the center of the width between the openings adjacent to the second direction. A method for manufacturing a display device.