JP2011060518A - Organic electroluminescent element, method of manufacturing the same, and light-emitting display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an organic EL element, the method simplifying processes and expanding a pixel area having no uneven luminance and no uneven luminescent colors, and to provide the organic EL element. <P>SOLUTION: The method of manufacturing the organic electroluminescent element includes at least: a step of preparing a substrate 1 having a first electrode 2 formed in a pattern corresponding to a pixel; a step of forming organic layers 3, 4 including at least a hole injection functional layer on an entire surface covering the first electrode 2 by an organic material containing a low molecular compound or an inorganic compound; a step of forming an opening part 10 corresponding to the pixel by forming a barrier plate 5 having a prescribed pattern on the organic layers 3, 4 by a direct drawing method; a step of forming the organic layers by applying an organic material composing a portion or all of an organic EL layer excluding the organic layers in the opening part 10 surrounded by the barrier plates 5; and a step of forming the second electrode on the organic EL layer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an organic electroluminescent element, a method for manufacturing the same, and a light emitting display device, and more specifically, an organic electroluminescent element capable of simplifying the process and expanding a pixel area free from luminance unevenness and light emitting color unevenness. The present invention relates to a manufacturing method, an organic electroluminescence element obtained by the method, and a light-emitting display device.

  An organic electroluminescence element (referred to as an organic EL element) is an element that sandwiches an organic EL layer between a pair of electrodes and applies a voltage between the electrodes to emit light from the light emitting material in the organic EL layer. In an organic EL element, a light emitting layer or the like is usually formed in a pattern so that the light emission color differs for each pixel. As a means for forming such a light emitting layer or the like, a method of vacuum-depositing a light emitting material or the like through a shadow mask, a method of applying a light emitting material or the like dissolved in an organic solvent to a predetermined site by inkjet, nozzle coating, dispenser or screen printing, etc. There is a method of destroying and removing a specific portion of the light emitting material and the like by irradiation with ultraviolet rays after being formed on the entire surface.

  Among them, a method of wet-coating a light-emitting layer or the like by an ink-jet method or a nozzle coating method has high material utilization efficiency and is advantageous in terms of manufacturing cost, and various studies have been made for practical use. Since such a coating method applies a fluid organic material ink, as shown in FIG. 8 and FIG. 9, usually, adjacent organic substrates on the substrate 101 are defined in order to define a pixel region which is an organic material ink application region. In general, an insulating layer 105 and a partition wall 106 are provided between the first electrodes.

  8A is a cross-sectional view between adjacent first electrodes 102 and 102 when no insulating layer is provided, and FIG. 8B is an adjacent first electrode when the insulating layer 105 is provided. It is a cross-sectional form figure between 102,102. In the case where the insulating layer is not provided, the light emitting layer 104 is thin at the peripheral edge 103 of the first electrode 102 sharply etched by wet etching, as shown in FIG. Therefore, there is a possibility that the first electrode 102 and a second electrode (not shown) to be formed later are short-circuited. On the other hand, as shown in FIG. 8B, the peripheral edge 103 of the first electrode 102 that has been sharply etched is provided by providing the insulating layer 105 so as to extend over the peripheral edges 103 and 103 of the first electrodes 102 and 102, respectively. Can be covered with an insulating layer 105. As a result, the first electrode 102 is not short-circuited with the second electrode formed thereafter.

  In addition, as shown in FIG. 9, when an organic layer is formed by applying and drying an organic material ink in the pixel region 110 (opening) surrounded by the partition wall 106 by an ink jet method or a nozzle coating method, The thickness of the peripheral portion 111 of the pixel region 110 becomes thicker than that of the central portion 112 due to the spread of the meniscus and ink. Such a difference in film thickness within the pixel region 110 causes display unevenness such as brightness unevenness and light emission color unevenness when the organic EL layer emits light.

  In order to deal with such a problem, for example, Patent Documents 1 to 3 propose a method of making the film thickness of the organic layer uniform within and between the pixels. In Patent Document 1, by making the application area of the ink containing the organic material and the solvent larger than the effective optical area, the environment around the ink applied in the effective optical area and the drying are made uniform, and within and between the pixels. The thickness of the organic layer is made uniform. Moreover, in patent document 2, the ink containing an organic material and a solvent is apply | coated to an effective optical area | region, and only the solvent is apply | coated to an ineffective optical area | region, and the peripheral part and center part of the application | coating area | region where ink was apply | coated The solvent molecular partial pressure is made equal, and the film thickness of the organic layer is made uniform within and between pixels.

  On the other hand, the partition may be formed at a stage during the formation of the organic EL layer, not before the formation of the organic EL layer. For example, in Patent Document 4, a buffer layer (referred to a hole injection layer or a hole transport layer) is formed so as to cover an electrode pattern, and then a partition is formed by photolithography, and an opening formed by the partition is formed. There has been proposed a method in which a light emitting layer is formed by applying and drying ink for a light emitting layer in an ink-jet method. This method is intended to produce an organic EL element having a multilayer structure in a simple and inexpensive manner, and is particularly characterized in that a buffer layer is formed of a curable material in order to form partition walls by photolithography.

JP 2002-222695 A JP 2006-269325 A JP 2009-54608 A JP 2007-242272 A

  However, in the methods of Patent Documents 1 and 2, an extra area for applying ink or solvent is required in addition to the effective optical area, and the effective optical area becomes small. Furthermore, in the method described in Patent Document 1, the utilization efficiency of the organic EL material is low. Therefore, there is room for improvement in the method of making the film thickness of the organic layer uniform within and between the pixels. Moreover, in patent document 3, selection of a solvent and the evaporation rate of a solvent are restrict | limited.

  In the method of Patent Document 4, the partition wall can be formed by a photolithography method by forming the buffer layer with a curable material. However, this method has a drawback that the material for forming the buffer layer is limited to a curable material layer that can withstand a developing solution and an etching solution in a photolithography method. That is, there is a drawback that the buffer layer cannot be formed of a material containing a low molecular compound.

  The objective of this invention is providing the manufacturing method of the organic electroluminescent element which can enlarge a pixel area which can simplify a process and does not have a brightness nonuniformity and light emission color nonuniformity. Another object of the present invention is to provide an organic electroluminescent element obtained by the method and a light emitting display device including the organic electroluminescent element.

  In order to solve the above problems, an organic electroluminescence device manufacturing method according to the present invention includes a step of preparing a substrate having a first electrode formed in a pattern corresponding to a pixel, and at least an entire surface covering the first electrode. A step of forming an organic layer including a hole injection functional layer with an organic material including a low molecular compound or an inorganic compound, and an opening corresponding to the pixel by forming a partition having a predetermined pattern on the organic layer by a direct drawing method Forming an organic layer by applying an organic material constituting a part or all of the organic EL layer excluding the organic layer in the opening surrounded by the partition, and on the organic EL layer And a step of forming a second electrode.

  According to this invention, first, an organic layer including at least a hole injection functional layer is formed on the entire surface covering the first electrode with an organic material including a low molecular compound or an inorganic compound, and then a predetermined pattern is formed on the organic layer. A partition is formed by a direct drawing method to form an opening corresponding to a pixel, and then an organic material constituting a part or all of the organic EL layer excluding the organic layer is applied in the opening surrounded by the partition To form an organic layer. Through these procedures, the number of organic layers applied and formed in the openings is reduced, so fluid organic material inks applied in the openings have traditionally had ink meniscus and ink spreading methods. (See FIG. 9), the flat area of the organic layer coated and formed in the opening, which is the pixel area (a flat area where luminance unevenness and emission color unevenness do not occur) extends to the vicinity of the partition wall. Can be enlarged. As a result, display unevenness such as luminance unevenness and light emission color unevenness when the organic EL layer emits light can be suppressed. In addition, according to the present invention, the barrier ribs having a predetermined pattern are directly formed on the organic layer by the drawing method, so that there is a problem as in the case of applying the photolithography method (damage to the organic layer by the developer or the etching solution). The partition can be formed on the organic layer made of an organic material containing a low molecular compound or an inorganic compound.

  In the method for manufacturing an organic electroluminescence device according to the present invention, the organic layer including at least the hole injection functional layer is formed of a hole injection layer, a hole injection transport layer, and a hole injection layer and a hole transport layer. It is preferable to be selected from laminates.

  In the method for producing an organic electroluminescence device according to the present invention, the low molecular compound is selected from arylamine derivatives, porphyrin derivatives, carbazole derivatives, anthracene derivatives, phthalocyanine compounds, and thiophene derivatives, and the inorganic compound is vanadium, molybdenum. It is preferably selected from metal oxides and metal complex compounds of ruthenium, aluminum and titanium.

  In the method for manufacturing an organic electroluminescence element according to the present invention, the direct drawing method is preferably selected from a printing method, a transfer method, a spray method using a stencil mask, a droplet discharge method, and a liquid column discharge method.

  In the method of manufacturing an organic electroluminescence element according to the present invention, it is preferable that the organic material is applied by a droplet discharge method or a liquid injection method.

  In order to solve the above problems, an organic electroluminescence element of the present invention includes a substrate, a first electrode formed in a pattern corresponding to a pixel on the substrate, and at least a positive electrode formed on the entire surface covering the first electrode. An organic layer including a hole injecting functional layer; a partition that forms an opening corresponding to the pixel on the organic layer; and the organic that forms part or all of the organic EL layer in the opening surrounded by the partition It has at least an organic EL layer in which an organic layer other than the layers is formed, and a second electrode formed on the organic EL layer.

  In this organic electroluminescence device, the organic layer including at least the hole injection functional layer is formed of an organic material including a low molecular compound or an inorganic compound, the partition is formed by a direct drawing method, and the organic layer is formed in the opening. Is formed by applying an organic material. In other words, according to the present invention, the number of organic layers applied and formed in the openings is reduced, so that the organic layer has a mode in which the ink meniscus and the spread of ink at the time of application are the same as in the past (see FIG. 9), the flat area of the organic layer applied and formed in the opening, which is the pixel area, expands to the vicinity of the partition wall. As a result, display unevenness such as luminance unevenness and light emission color unevenness when the organic EL layer emits light can be suppressed. In addition, according to the present invention, the partition wall having a predetermined pattern is formed directly on the organic layer by a drawing method, so that there is a problem as in the case of applying the photolithography method (damage to the organic layer by the developer or the etching solution). ) And partition walls can be formed on an organic layer made of an organic material containing a low molecular compound or an inorganic compound.

  In the organic electroluminescence device according to the present invention, the organic layer including at least the hole injection functional layer is a hole injection layer, a hole injection transport layer, and a laminate of a hole injection layer and a hole transport layer, Is preferably selected from.

  In the organic electroluminescence device according to the present invention, the low molecular compound is selected from arylamine derivatives, porphyrin derivatives, carbazole derivatives, anthracene derivatives, phthalocyanine compounds, and thiophene derivatives, and the inorganic compound is vanadium, molybdenum, ruthenium, It is preferably selected from metal oxides and metal complex compounds of aluminum and titanium.

  In order to solve the above-described problems, a light-emitting display device according to the present invention uses the organic electroluminescence element according to the present invention as a passive matrix or active matrix EL panel.

  According to the organic electroluminescence device and the method for manufacturing the same according to the present invention, the fluid organic material ink applied in the opening does not have a conventional manner in terms of ink meniscus and ink spreading, and the pixel The flat portion region of the organic layer applied and formed in the opening which is the region can be expanded to the vicinity of the partition wall. As a result, display unevenness such as luminance unevenness and light emission color unevenness when the organic EL layer emits light can be suppressed. In addition, since the barrier ribs of a predetermined pattern are formed directly on the organic layer by a drawing method, there is no problem (damage to the organic layer by a developer or an etching solution) as in the case of applying a photolithography method, and a low molecular compound Alternatively, the partition wall can be formed over an organic layer formed of an organic material containing an inorganic compound.

  According to the light-emitting display device according to the present invention, by using the organic electroluminescence element according to the present invention, it can be applied to either a passive matrix method or an active matrix method, and in any case, an image with suppressed display unevenness can be provided.

It is a typical perspective view which shows the form of the partition with which the organic electroluminescent element which concerns on this invention is provided. It is typical sectional drawing which shows an example of the organic electroluminescent element which concerns on this invention. It is typical sectional drawing which shows the manufacturing method (the 1) of the organic electroluminescent element which concerns on this invention. It is typical sectional drawing which shows the manufacturing method (the 2) of the organic electroluminescent element which concerns on this invention. It is typical sectional drawing which shows the process of apply | coating the whole organic layer after providing an insulating layer in the clearance gap between 1st electrodes. It is typical sectional drawing which shows the relationship between the clearance gap between 1st electrodes, and the width | variety of a partition. It is typical sectional drawing which shows another example of the organic electroluminescent element which concerns on this invention. They are a cross-sectional view (A) between adjacent first electrodes when an insulating layer is not provided, and a cross-sectional view (B) between adjacent first electrodes when an insulating layer is provided. It is sectional drawing of the pixel area | region at the time of providing the conventional insulating layer and the partition.

  Hereinafter, the organic electroluminescence element (organic EL element), the manufacturing method thereof, and the light-emitting display device of the present invention will be described in detail. Note that the present invention can be variously modified within a range including its characteristic configuration, and is not limited to the contents described in the following description and drawings.

[Organic EL device and manufacturing method thereof]
As shown in FIGS. 1 to 4 and 7, the organic EL device according to the present invention includes a substrate 1, a first electrode 2 formed in a pattern corresponding to a pixel on the substrate 1, and a first electrode 2. An organic layer (3-4 or 3) including at least a hole injection functional layer formed on the entire surface to be covered; and a partition wall 5 for forming an opening 10 corresponding to the pixel on the organic layer (3, 4 or 3); An organic layer (6 or 4, 6) other than the organic layer (3 to 4 or 3) constituting part or all of the organic EL layer 11 is formed in the opening 10 surrounded by the partition wall 5 It has at least the EL layer 11 and the second electrode 9 formed on the organic EL layer 11.

  In this organic EL element, at least the organic layer (3 to 4 or 3) including the hole injection functional layer is formed of an organic material including a low molecular compound or an inorganic compound, and the partition wall 5 is formed by a direct drawing method. The organic layer (6 or 4, 6) formed in the part 10 is formed by applying an organic material.

  An organic EL element illustrated in FIG. 1A is an example of an EL panel applied to a passive matrix light-emitting display device, and the opening 10A included in the organic EL element is in one direction (the Y direction in FIG. 1A). ). On the other hand, the organic EL element shown in FIG. 1B is an example of an EL panel applied to an active matrix light emitting display device, and each opening 10B included in the organic EL element constitutes an individual unit pixel. Yes. In FIG. 1B, reference numeral 32 denotes a TFT, reference numeral 31 denotes a wiring via to the TFT, reference numeral 1a denotes a base substrate, and reference numeral 1b denotes a TFT substrate on which the TFT is formed.

  As shown in FIGS. 3A to 4H, a method for manufacturing an organic EL element according to the present invention includes a step of preparing a substrate 1 having a first electrode 2 formed in a pattern corresponding to a pixel. A step of forming an organic layer (3, 4 or 3) including at least a hole injection functional layer on the entire surface covering the first electrode 2 with an organic material including a low molecular compound or an inorganic compound, and the organic layer (3,4) Or 3) a step of forming a partition 5 having a predetermined pattern on the top by a direct drawing method to form the opening 10 corresponding to the pixel, and one of the organic EL layers 11 in the opening 10 surrounded by the partition 5 It includes at least a step of forming an organic layer (6 or 4, 6) by applying an organic material constituting a part or the whole, and a step of forming the second electrode 9 on the organic EL layer 11.

  In the present invention, the organic EL layer 11 is laminated between the first electrode 2 and the second electrode 9. Usually, the first electrode 2 on the substrate 1 side is an anode, and the second electrode 9 provided above the organic EL layer 11 is often a cathode. In such an example, the organic EL layer 11 is formed from the anode (first electrode 2) side to the cathode (second electrode 9) side, for example, hole injection layer 3 / hole transport layer 4 / light emitting layer 6 / electron. It is configured as a laminated structure of organic layers such as transport layer 7 / electron injection layer 8 and the like.

  As shown in FIGS. 1 to 4 and 7, the present invention is characterized in that a part or all of each organic layer constituting the organic EL layer 11 is formed by coating with fluid organic material ink. It is a technology that can be applied effectively. Specifically, the organic layer formed before forming the partition walls 5 is formed of a solid material with an organic material containing a low molecular compound or an inorganic compound, and the organic layer is formed on the organic layer. This is characterized in that the partition walls 5 are formed by a direct drawing method. The partition wall 5 acts so as to define the opening 10 corresponding to the pixel.

  Hereinafter, the configuration of the present invention will be described in detail in the order of the manufacturing steps in FIGS. 3 (A) to 4 (H). In the following description, the first electrode 2 is an anode, the second electrode 9 is a cathode, and from the first electrode 2 side, a hole injection layer 3 / a hole transport layer 4 / a light emitting layer (including a light emitting material). Layer) An organic EL layer 11 having a five-layer structure composed of 6 / electron transport layer 7 / electron injection layer 8 will be described. However, the present invention is not limited to this.

(Board preparation process)
First, as shown in FIG. 3A, a substrate 1 having a first electrode 2 formed in a pattern corresponding to a pixel is prepared. The substrate 1 to be prepared may be (i) an electrode pattern corresponding to a pixel already formed, or (ii) a first electrode layer formed on the entire surface of the substrate 1 and then photolithography. An electrode pattern corresponding to the pixel may be formed by patterning, or (iii) a resist pattern is formed on the substrate, and then a first electrode layer is formed on the entire surface and lifted off to form a pixel. A corresponding electrode pattern may be formed.

  The material, transparency, thickness, etc. of the substrate 1 are not particularly limited, and those having properties as required can be arbitrarily adopted. Examples thereof include inorganic materials such as quartz, glass and silicon wafers, and polymer materials such as polycarbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES). Whether the substrate is a transparent substrate or an opaque substrate can be arbitrarily selected depending on whether the light extraction side is the first electrode side, the second electrode side, or both sides.

  As shown in FIG. 1B, a TFT substrate 1 (1a, 1b) on which a TFT (thin film transistor) 32 is formed is used as a part of an organic EL element substrate used in an active matrix light emitting display device. It is done.

  The first electrode 2 is formed in a pattern corresponding to the pixel. A preferred constituent material is selected depending on whether the first electrode 2 is an anode or a cathode, and a preferred constituent material is also selected whether or not the first electrode 2 is on the light extraction side. Various materials are selected and used as such constituent materials.

  When the 1st electrode 2 is an anode which supplies a hole to the organic EL layer 11, for example, a metal simple substance, an alloy, a conductive metal oxide (transparent conductive film), a conductive inorganic compound, a conductive polymer, etc. are mentioned. Can do. These materials may be used singly or in combination of two or more, or two or more layers may be laminated. It should be noted that ITO and IZO, which are transparent conductive films, are particularly preferably used when the first electrode 2 is made transparent and light is extracted also from the first electrode 2 side.

  The thickness of the 1st electrode 2 is not specifically limited, It sets suitably according to the electroconductive material to be used. Specifically, the thickness of the anode 2 is preferably in the range of 5 nm to 1000 nm, more preferably in the range of 40 nm to 500 nm. Examples of film forming means for the first electrode 2 include physical vapor deposition methods such as chemical vapor deposition, vacuum deposition, sputtering, and ion plating.

  The patterned first electrode 2 is formed by forming the first electrode layer on the entire surface of the substrate 1 by the film forming means and then patterning by photolithography, or forming a resist pattern on the substrate 1. Thereafter, the first electrode layer is formed on the entire surface including the resist pattern by the film forming means, and is patterned by lift-off.

  In the case of the passive matrix system shown in FIG. 1A, the patterned first electrode 2 is provided as an electrode extending in a strip shape or a stripe shape in one direction (Y direction). The pitch of the strip-shaped or striped electrode patterns is preferably equal. The pattern width is set to an arbitrary value depending on the display size and resolution.

  A gap G (see FIG. 3A) is formed on the outer periphery of the first electrode pattern except for the connection wiring portion to the first electrode 2. In the passive matrix method, a strip-shaped or striped second electrode 9 is provided via the organic EL layer 11, and the second electrode 9 has a direction in which the first electrode 2 shown in FIG. It is provided to be orthogonal.

  On the other hand, in the case of the active matrix system shown in FIG. 1B, the patterned first electrode 2 is provided as a pixel electrode constituting a unit pixel. Examples of the shape of the first electrode 2 in this case include a point-symmetric shape such as a circle and a square, and a shape that is not point-symmetric such as a rectangle, a track shape, and an ellipse but is line-symmetric. The pattern arrangement can be a mosaic arrangement, a delta arrangement, or the like. Furthermore, it is preferable that the pattern pitch is equally spaced vertically and horizontally. The size of the pattern is not particularly limited, and is appropriately selected according to the shape of the first electrode pattern. For example, it is appropriately selected according to the shape of the first electrode pattern, the display size, and the resolution. For example, if the shape of the first electrode pattern is circular, the diameter can be about 20 μm to 200 μm.

  The width W1 of the gap G formed between the first electrodes is arbitrarily set depending on the display size and resolution, and is not particularly limited, but is usually 15 to 60 μm when a normal general full-color display is assumed. Depending on the types of the substrate 1 and the first electrode 2, an adhesive layer, a thermal buffer layer, a gas barrier layer, or the like may be optionally provided as a base layer of the first electrode 2.

(Organic layer forming step 1)
Next, as shown in FIG. 3B, an organic layer (3, 4) including at least a hole injection functional layer is formed on the entire surface covering the first electrode 2 with an organic material including a low molecular compound or an inorganic compound. . The term “entire surface” used herein means “all the regions where it is desirable to share the organic layers 3 and 4”, and is not necessarily the entire surface on the substrate 1, but the entire surface on the substrate 1. It does not matter. The organic layer 3 exemplified here is the “hole injection layer 3”, and the organic layer 4 is the “hole transport layer 4”.

  In the organic layer forming step illustrated in FIG. 3B, an organic layer (hole transport layer 4 in the example of FIG. 3C) on which a partition wall 5 to be described later is placed with an organic material containing a low molecular compound or an inorganic compound. It is characterized by forming.

  In the case where the hole injection layer 3 and the hole transport layer 4 are stacked before the partition wall 5 is formed as in the examples of FIGS. 2 to 4, at least the hole transport layer 4 is formed of a low molecular compound or inorganic material. In the case of forming with an organic material containing a compound, the present invention (the invention in which the partition wall 5 is formed by a direct drawing method, not a photolithography method that damages an organic layer containing a low molecular compound or an inorganic compound) is preferably applied. The In this case, the hole injection layer 3 is not necessarily formed of an organic material containing a low molecular compound or an inorganic compound.

  Further, as in the example of FIG. 7, when the partition wall 5 is formed after the hole injection layer 3 is formed, the hole injection layer 3 on which the partition wall 5 is placed is formed of an organic material containing a low molecular compound or an inorganic compound. In this case, the present invention (invention in which the partition walls 5 are formed by a direct drawing method rather than a photolithography method that damages an organic layer containing a low molecular compound or an inorganic compound) is preferably applied.

  Here, the “low molecular compound or inorganic compound” is a low molecular compound or an inorganic compound that is damaged by a developer or an etching solution in a photolithography method and cannot exhibit the desired characteristics. The “organic material containing a low molecular compound or an inorganic compound” means an organic material containing the low molecular compound or inorganic compound as a main compound. For example, it may be an organic material consisting only of a low molecular compound, an organic material containing a high molecular compound or a dopant together with a low molecular compound, or an organic material containing a high molecular compound or a dopant together with an inorganic compound. It may be. In addition, the blending ratio of the low molecular compound or the inorganic compound is qualitatively low when the partition 5 described later is formed by a photolithography method so that the damage increases and the function of the organic layer is reduced. This is a case where a compound is contained, and quantitatively, a case where the weight ratio of the low molecular weight compound or the inorganic compound is 5 to 100%.

  The organic layer formed of an organic material containing a low molecular compound or an inorganic compound (at least the organic layer immediately below the partition wall) is a solvent-containing type (solvent type) organic material ink, even if it is formed by vacuum deposition Alternatively, a non-solvent type (non-solvent type) organic material ink may be applied and formed. In addition, when forming by vacuum vapor deposition, you may form in all the predetermined area | regions where it is desirable to share the organic layers 3 and 4 by mask vapor deposition. On the other hand, the organic layer which is not necessarily formed of an organic material containing a low molecular compound or an inorganic compound because it is not directly under the partition wall may be formed by coating with an organic material mainly containing a high molecular compound, You may vacuum-deposit or apply | coat form with the organic material which mainly contains a compound or an inorganic compound.

  In the vacuum evaporation method, an organic material containing a low molecular compound or an inorganic compound is evaporated to form a film. On the other hand, there are various specific methods for coating methods, such as printing methods, ink jet methods, spin coating methods, casting methods, dip coating methods, bar coating methods, blade coating methods, roll coating methods, gravure coating methods, Examples of the application method include a flexographic printing method and a spray coating method.

  The organic layers 4 and 5 thus formed are flat layers as shown in FIG. The thickness of the organic layer varies depending on whether the organic layer is the hole injection layer 3 or the hole transport layer 4. Therefore, it is formed of an organic material so as to have a thickness suitable for each layer.

  Examples of the material for the hole injection layer include conductive polymers such as arylamine derivatives, porphyrin derivatives, carbazole derivatives, polyaniline derivatives, polythiophene derivatives, and polyphenylene vinylene derivatives. Specifically, as the arylamine derivative, bis (N- (1-naphthyl-N-phenyl) benzidine (α-NPD), N, N′-bis- (3-methylphenyl) -N, N′- Bis- (phenyl) -benzidine (TPD), copoly [3,3′-hydroxy-tetraphenylbenzidine / diethylene glycol] carbonate (PC-TPD-DEG), 4,4,4-tris (3-methylphenylphenylamino) Triphenylamine (MTDATA), etc. Examples of the carbazole derivative include polyvinyl carbazole (PVK), and examples of the polythiophene derivative include poly (3,4-ethylenedioxythiophene) -polystyrene sulfonic acid (PEDOT-PSS). The porphyrin derivatives and arylamines mentioned above The derivative or the like may be mixed with an inorganic oxide such as a Lewis acid, tetrafluorotetracyanoquinodimethane (F4-TCNQ), iron chloride, vanadium, molybdenum, etc. As a material for the hole injection layer, Mention may be made of metal oxides or metal complex compounds such as vanadium, molybdenum, ruthenium, aluminum and titanium.

  When the hole injection layer 3 is not provided as a lower layer of the partition wall 5 (examples in FIGS. 2 to 4), the hole injection layer material may be a low molecular compound, an inorganic compound, or a high molecular compound. It can be preferably applied to the case where the hole injection layer 3 is formed of an organic material containing a low molecular compound or an inorganic compound, and the hole injection layer 3 is provided as a lower layer of the partition wall 5 (example in FIG. 7). As such organic materials, among the above, organic materials containing low molecular organic compounds selected from arylamine derivatives, porphyrin derivatives, carbazole derivatives, anthracene derivatives, phthalocyanine compounds and thiophene derivatives, vanadium, molybdenum, ruthenium, aluminum, An organic material containing an inorganic compound selected from metal oxides such as titanium and metal complex compounds can be preferably exemplified.

  Examples of the material for the hole transport layer include arylamine derivatives, anthracene derivatives, carbazole derivatives, thiophene derivatives, fluorene derivatives, distyrylbenzene derivatives, and spiro compounds. Specific examples of the arylamine derivative include bis (N- (1-naphthyl-N-phenyl) -benzidine (α-NPD), N, N′-bis- (3-methylphenyl) -N, N′-bis. -(Phenyl) -benzidine (TPD), 4,4,4-tris (3-methylphenylphenylamino) triphenylamine (MTDATA), copoly [3,3'-hydroxy-tetraphenylbenzidine / diethylene glycol] carbonate (PC -TPD-DEG), etc. Specific examples of anthracene derivatives include 9,10-di-2-naphthylanthracene (DNA), poly [(9,9-dioctylfluorenyl-2,7- Diyl) -co- (9,10-anthracene)], etc. Specific examples of the carbazole derivative include 4 4-N, N′-dicarbazole-biphenyl (CBP), polyvinylcarbazole (PVK), etc. Specific examples of the thiophene derivative include poly [(9,9-dioctylfluorenyl-2,7 -Diyl) -co- (bithiophene)] etc. Specific examples of the fluorene derivative include poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (4,4 '-(N- (4-sec-butylphenyl)) diphenylamine)] (TFB), etc. Specific examples of the distyrylbenzene derivative include 1,4-bis (2,2-diphenylvinyl). Benzene (DPVBi), etc. Specific examples of the spiro compound include poly [(9,9-dioctylfluorenyl-2,7-diyl)- lt-co-. (9,9'-spiro - bifluorene-2,7-diyl)], and the like may be used in combination of two or more may be used these materials alone.

  The present invention is preferably applied to the case where the hole transport layer 4 is formed of an organic material containing a low molecular compound or an inorganic compound, and the hole transport layer 4 is provided as a lower layer of the partition wall 5 (examples of FIGS. 2 to 4). it can. As such organic materials, among the above, organic materials containing low molecular compounds such as arylamine derivatives, anthracene derivatives, carbazole derivatives, thiophene derivatives, and organic materials containing metal complex compounds can be preferably exemplified. When the hole transport layer 4 is not provided as the lower layer of the partition wall 5 (example in FIG. 7), the hole transport layer material may be a low molecular compound, an inorganic compound, or a high molecular compound.

  Examples of the solvent contained in the solvent-type organic material include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; alcohols such as methanol, ethanol, 2-propanol, n-butanol, and 2-ethoxyethanol. Aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, p-cymene and diisopropylbenzene; ester systems such as ethyl acetate, isobutyl acetate, butyl acetate and methyl propionate; diethyl ether, diisopropyl ether and tert-butyl methyl Ethers such as ether, cyclopentyl methyl ether, dimethoxyethane, ethylene glycol diethyl ether, tetrahydrofuran, 1,4-dioxane; pentane, hexane, heptane, octa , Decane, dodecane, undecane, cyclohexane, aliphatic hydrocarbons decalin; dichloromethane, 1,2-dichloroethane, chloroform, o- halogenated aromatic hydrocarbons dichlorobenzene, and the like.

  As described above, in this organic layer forming step, an organic material containing a low molecular compound or an inorganic compound is used as the material for forming the organic layer that is the lower layer of the partition wall 5, and an organic layer made of the organic material is formed on the entire surface. If it has such a feature, the organic layer may be a stacked layer of a hole injection layer 3 and a hole transport layer 4 as shown in FIGS. 2 to 4, or a single layer of the hole injection layer 3 as shown in FIG. It may be a layer.

  Further, when the white light emitting layer can be shared by each pixel and can be formed of an organic material containing a low molecular compound or an inorganic compound, as in the method of combining the white light emitting layer and the color filter, the white light emitting layer is also an organic layer. You may form in the whole surface at a formation process. The same applies to the electron transport layer and the electron injection layer.

  In addition, when the blue light emitting layer can be shared by each pixel and can be formed of an organic material containing a low molecular compound or an inorganic compound, as in a color conversion method that combines a blue light emitting layer and a color filter, the blue light emitting layer is also used. You may form in the whole surface at an organic layer formation process. The same applies to the electron transport layer and the electron injection layer.

  The structure of the organic EL layer 11 is other than the five-layer type (hole injection layer 3, hole transport layer 4, light emitting layer 6, electron transport layer 7, electron injection layer 8) exemplified in FIGS. For example, a single-layer organic layer composed of a light-emitting layer, a two-layer organic layer composed of a hole injection / transport layer / a light-emitting layer, and a two-layer structure composed of a light-emitting layer / an electron injection / transport layer An organic layer, an organic layer having a three-layer structure including a hole injecting and transporting layer / a light emitting layer / an electron injecting and transporting layer can be exemplified. In addition, an optional layer may be omitted from the organic EL layer having a five-layer structure as necessary, and holes or electrons can be prevented from penetrating like a hole blocking layer or an electron blocking layer. Further, a layer added to prevent exciton diffusion and confine excitons in the light emitting layer to increase recombination efficiency may be added. In any case, these various layer structures are applicable as long as they have the characteristics of the present invention.

  FIG. 5 is a schematic cross-sectional view showing a step of coating the entire surface of the organic layer (3, 4) after the insulating layer 16 is provided in the gap G between the first electrodes 2 and 2. As shown in FIG. Unlike the case of FIG. 3B, the organic layers (3, 4) may be applied and formed on the entire surface after the insulating layer 16 is provided in the gap G between the first electrodes 2 and 2.

  FIG. 5A shows a form after the first electrode 2 is patterned on the substrate 1, and reference numeral G denotes a gap between the first electrodes. FIG. 5B shows an example in which an insulating layer 16 is provided in the gap G. Examples of the material for forming the insulating layer 16 include novolac resins, polyimides, and acrylates. Examples of the means for forming the insulating layer 16 include photolithography. The thickness of the insulating layer 16 is preferably the same as or substantially the same as the thickness of the first electrode pattern. By doing so, the surface 17 to be formed in which the insulating layer 16 is provided in the gap G between the first electrodes is less uneven. As a result, the organic layer (3, 4) formed by coating the entire surface 17 to be formed can be formed as a uniform layer with small unevenness.

  The thickness of the insulating layer 16 that can reduce the unevenness of the formation surface 17 is preferably within a range of ± 20% of the thickness of the first electrode pattern, and this range is referred to as “substantially the same”. When the thickness of the insulating layer 16 is formed to be thicker than the thickness of the first electrode pattern within the range, the dimension that the insulating layer 16 protrudes outside the gap G is preferably about 0 to +0.05 μm.

  FIG. 5 (C) shows a form in which the organic layer (3, 4) is applied and formed after the insulating layer 16 is provided in the gap G between the first electrodes. FIG. 5 (D) shows a partition on the organic layer. This is a form provided by the direct drawing method. As shown in FIG. 5D, the partition wall 5 is provided above the insulating layer 16 provided in the gap G between the first electrodes via an organic layer (3, 4). This form is different from the conventional two-stage partition (insulating film 105, partition 106) shown in FIG.

(Partition forming process)
Next, as shown in FIG. 3C, a partition 5 having a predetermined pattern is directly formed on the organic layer by a drawing method. By forming the partition wall 5, an opening 10 corresponding to the pixel is formed, and an organic material ink 6 ′ is applied to the opening 10 in an organic layer forming process described later. Such partition walls 5 are formed on the organic layer formed of an organic material containing a low molecular compound or an inorganic compound by the organic layer forming step described above.

  The partition walls 5 are formed directly on the organic layer by a drawing method. Specifically, in the example of FIGS. 2 and 3C, it is formed directly on the hole transport layer 4 by the drawing method, and in the example of FIG. 7, it is formed directly on the hole injection layer 3 by the drawing method. In this step, since the partition walls 5 having a predetermined pattern are formed directly on the organic layer 4 by a drawing method, there is no problem (damage to the organic layer due to a developer or an etching solution) as in the case of applying a photolithography method. A partition can be formed without any problem on an organic layer made of an organic material containing a low molecular compound or an inorganic compound.

  The direct drawing method may be any method other than the formation method in which exposure and development are performed after the partition wall material is formed on the entire surface as in the photolithography method. For example, the printing method, the transfer method, the droplet discharge method, and the liquid column discharge And a spray method using a stencil mask.

  Examples of the printing method include a printing method that allows direct drawing, and examples include a gravure printing method and a screen printing method. By such a printing method, the partition wall 5 can be formed by directly drawing the partition wall material.

  As the transfer method, (i) a transfer sheet in which a partition wall material is patterned on the base sheet by the gravure printing, screen printing method, etc., the partition pattern is transferred from the transfer sheet, A sheet transfer method for forming the partition walls 5; (ii) a partition wall material is formed on the entire surface of the substrate sheet by gravure coating, casting coating, bar coating, blade coating, etc. to form a donor sheet, and the donor sheet is an organic layer (4) heat transfer method to transfer the pattern onto the base sheet by applying heat to the pattern part of the donor sheet from the base side of the donor sheet instantaneously with a thermal head. A light-to-heat conversion layer is formed, and a partition wall material is formed and laminated on the entire surface in the same manner as in (ii) above to form a donor sheet, and the donor sheet is adhered to the organic layer 4 to form a donor sheet. The laser transfer method etc. which irradiate a laser only to the required pattern part from the base material side of G and transfer a pattern etc. can be mentioned.

  The droplet discharge method is a general ink jet method in which ink is discharged from a nozzle in the form of droplets and landed on an object (organic layer 4). The size of the droplet is controlled by a piezoelectric element. The pattern formed on the object (organic layer 4) has a dot shape or a line shape in which dots are superimposed. On the other hand, the liquid injection and discharge method is a method in which ink is continuously extruded from a nozzle and discharged as a liquid injection instead of droplets, and is applied in a line form on an object (organic layer 4). It is a method represented by the law. In this liquid column discharge method, it cannot be formed in a dot shape like the droplet discharge method.

  The shape of the partition wall 5 is not particularly limited, but the cross-sectional shape thereof is a forward tapered shape (a bottom spreading shape having a lower bottom width wider than the upper bottom width; see FIGS. 1 and 2, etc.) or a rectangular shape (upper The bottom width and the lower bottom width are the same shape (see FIG. 7). Moreover, as shown in FIG. 1 etc., the integrally formed structure may be sufficient and the laminated structure formed in two or more steps may be sufficient. The partition wall 5 having an integral structure can be formed by all of the partition wall forming means described above, but the partition wall 5 having a laminated structure can be formed by a droplet discharge method and a liquid column discharge method.

  The partition wall 5 is formed above the gap G formed on the outer periphery of the patterned first electrode 2 via the organic layers 3 and 4. In the case of the passive matrix type electrode pattern shown in FIG. 1A, above the gap G surrounding the strip-shaped or stripe-shaped first electrode 2 (excluding the connection wiring portion; the same applies hereinafter). A partition wall 5 is provided. On the other hand, in the case of the active matrix type electrode pattern shown in FIG. 1B, the partition wall 5 is provided above the gap G surrounding the first electrode 2 of the unit pixel pattern without a break. By surrounding the first electrode pattern with the partition wall 5 in a plan view, it becomes possible to apply organic material ink to the surrounded opening 10.

  The width W2 of the partition wall 5 is not particularly limited, and may be equal to or less than the width W1 of the gap G shown in FIG. The position of the partition wall 5 is not particularly limited, but the center of the width W2 of the partition wall 5 preferably coincides with the center of the width W1 of the gap G. By doing so, the organic EL layer 11 can be provided with symmetry on both sides of the partition wall 5.

  If the width W2 of the partition wall 5 is approximately equal to or less than the width W1 of the gap G, compared to the conventional embodiment shown in FIG. Adverse effects) can be suppressed.

  Here, the relationship between the width W1 of the gap G between the first electrodes 2 and 2 and the width W2 of the partition wall 5 will be described with reference to FIG. As shown in FIG. 6A, the width W2 of the partition wall 5 is smaller than the width W1 of the gap G and may be set back from the end portion (edge) 19 of the first electrode. As shown in B), it may be larger than the width W1 of the gap G and over the end (edge) 19 of the first electrode. The position of the partition wall 5 is not particularly limited, but it is preferable that the center 18 of the width W2 of the partition wall 5 coincides with the center of the width W1 of the gap G. By doing so, the organic EL layer 11 can be provided with symmetry on both sides of the partition wall 5.

  Although the width W2 of the partition wall 5 depends on the size of the width W1 of the gap G, it may be considerably smaller than the width W1 or may be approximately the same as the width W1. 6A is a receding width of the partition wall 5 when the width W2 of the partition wall 5 is smaller than the width W1 of the gap G between the first electrodes 2 and 2. The receding width W3 is large. Since the adverse effect (adverse effect of reducing the flat portion region a) due to the raised portion 12 on the partition wall side can be suppressed, the area of the flat portion region a of the organic layer formed thereafter can be increased (FIG. 2). The receding width W3 is 0 to 15 μm in absolute value, and is preferably symmetrical.

  On the other hand, as shown in FIG. 6B, when the width W2 of the partition wall 5 is larger than the width W1 of the gap G, and the position of the partition wall 5 exceeds the end (edge) 19 of the first electrode 2, It is desirable that the overpass width W4 is as small as possible. The smaller the overpass width W4, the more the adverse effect caused by the raised portion 12 on the partition wall side (the adverse effect of reducing the flat portion region a) can be suppressed. Therefore, the area of the flat portion region a of the organic layer formed thereafter is reduced. Can be increased (see FIG. 2). The passover width W4 is 0 to 5 μm in absolute value, and is preferably bilaterally symmetric.

  The height H of the partition wall 5 is not particularly limited, but should be high enough that the organic material ink 6 ′ does not flow into the adjacent opening 10 beyond the partition wall 5 in the subsequent application process of the organic material ink 6 ′. Is desirable. That is, even when an amount of organic material ink necessary for forming the organic layer 6 is applied, the height is preferably such that it does not flow into the adjacent opening 10. Such a height cannot be generally specified, but is usually about 0.5 to 5 μm.

  At least the upper surface 15 of the partition wall 5 is preferably liquid repellent. Since the upper surface 15 of the partition wall 5 has liquid repellency, when the organic material ink 6 ′ is applied to the opening 10 surrounded by the partition wall 5, the organic material ink flows into the adjacent opening 10. Can be prevented. The liquid repellency is more preferably the entire surface of the partition wall 5. The upper surface 15 of the partition wall 5 is the opposite surface on the substrate side, and the upper surface shape may be a flat surface as shown in FIGS. 2 and 7, a curved surface, or a sharp point. Good. If it is pointed, it can be rephrased as “upper part 15 of the partition wall 5” instead of “upper surface”.

  The liquid repellency in this application is the liquid repellency with respect to the organic material ink which has an organic solvent. As the evaluation of the liquid repellency, the contact angle with respect to a liquid having a surface tension of 29 mN / m (room temperature) is 40 ° or more in the wettability test measured with the same material as the partition wall 5 by the same method, preferably It is 45 ° or more, more preferably 50 ° or more. With such liquid repellency, the above-described effects can be achieved. In addition, when the result similar to this is measured by the contact angle with respect to water, the contact angle is 70 ° or more, preferably 75 ° or more, more preferably 80 ° or more. The same result as the liquid repellency with respect to can be obtained. The contact angle with the liquid was measured at a temperature of 23 ° C., and the contact angle with the liquid was measured using a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science Co., Ltd.). 30 seconds later) and obtained from the result.

  As a method for imparting liquid repellency to the partition wall 5, (i) a method for forming the partition wall 5 using a liquid repellent material, and (ii) a method for lyophobic the surface of the partition wall 5 after the partition wall 5 is formed. And so on. In addition, since the partition wall 5 is formed by a direct drawing method such as a printing method, a transfer method, a droplet discharge method, a liquid column discharge method as described above, it should be a material to which at least such a direct drawing method can be applied. It is a premise.

  (i) In the method of forming a partition using a liquid repellent material, examples of the liquid repellent material include a resin material having a liquid repellent property and a resin material to which a liquid repellent is added. Can do. Examples of the resin material in which the resin material itself has liquid repellency include fluorine resins such as polytetrafluoroethylene (PTFE), silicone resins, and the like. In this case, the resin material itself may use only a resin material having liquid repellency, or another general-purpose material may be mixed with the resin material. It should be noted that the following liquid repellent may be added to the resin material itself having liquid repellency as required.

  In the case of using a resin material to which a liquid repellent is added, the liquid repellent is not particularly limited as long as it does not adversely affect each organic layer (3,4, 6-8) constituting the organic EL layer 11. Examples thereof include a fluorine-based resin, a silicone-based resin, a copolymer oligomer having a perfluoroalkyl group-containing acrylate or methacrylate as a main component, and the like. Among them, it is preferable to use a copolymer oligomer mainly composed of a perfluoroalkyl group-containing acrylate or methacrylate. Moreover, as a commercial item, surflon (random type oligomer; manufactured by Seimi Chemical Co., Ltd.), Aron G (graft type oligomer; manufactured by Toa Gosei Chemical Co., Ltd.), Modiper F (block type oligomer; manufactured by NOF Corporation) and the like can be mentioned. it can. The amount of the liquid repellent added to the resin material varies depending on the type of liquid repellent and the type of resin, but is usually about 1 to 20 parts by weight, preferably 5 parts per 100 parts by weight of the resin material. It is in the range of 10 to 10 parts by weight.

  As a resin material in the case of using a resin material to which a liquid repellent is added, those generally used for partition walls can be used, and examples thereof include novolak resins, polyimides, and acrylates.

  (ii) In the method of lyophobizing the surface of the partition wall 5 after the partition wall 5 is formed, the constituent material of the partition wall 5 is not particularly limited as long as it can be lyophobized. What is used for a partition can be used, For example, a novolak-type resin, a polyimide, an acrylate etc. can be mentioned.

  The liquid repellent treatment method for the partition walls 5 is not particularly limited, and examples thereof include a surface treatment method using a liquid repellent treatment agent such as a silicone compound or a fluorine-containing compound. Note that the surface treatment method (plasma treatment) using plasma of fluorocarbon gas can be used as long as the characteristics of the organic layer 4 are not adversely affected.

(Organic layer forming step 2)
Next, as shown in FIG. 3D and FIG. 4E, an organic material ink 6 ′ constituting a part or all of the organic EL layer 11 is applied in the opening 10 surrounded by the partition walls 5. Thus, the organic layer 6 is formed. The organic material ink 6 ′ exemplified here is a light emitting layer ink, and the organic layer 6 is a light emitting layer. The organic material ink 6 ′ is a solvent-containing type (solvent type) organic material ink, and the organic layer 6 is formed by applying and drying the organic material ink 6 ′.

  Since at least the upper surface 15 (preferably the entire surface) of the partition wall 5 has liquid repellency, as shown in FIG. 3D, the organic material ink 6 ′ having fluidity in the opening 10 surrounded by the partition wall 5 is used. Is applied, the organic material ink 6 ′ rises beyond the partition wall 5 having liquid repellency without being mixed into the adjacent opening 10. Thereafter, as shown in FIG. 4E, the solvent in the organic material ink 6 'is volatilized by the drying process, and the organic layer 6 (light emitting layer 6) is formed.

  As shown in FIG. 2, the formed organic layer 6 has a raised portion 12 in the vicinity of the partition wall 5, but the flat portion region a in the opening 10 is on the side of the peripheral portion of the first electrode 2 constituting the pixel. Expand to. In the present invention, the partition wall 5 is provided on the organic layer 4 and the layer formed in the opening 10 is a single layer (light emitting layer 6). Therefore, as shown in FIG. As compared with the case where the hole transport layer 105 and the light emitting layer 106) are formed in the opening 110, the raised portion 111 (non-flat portion) at the peripheral edge of the first electrode 102 narrows the flat portion region a ′. Can be reduced.

  In addition, as shown in FIG. 7, it is necessary to change the hole transport material for each of R (red), G (green), and B (blue), or the thickness of the hole transport layer 4 corresponding to RGB is changed. When the RGB pixel configuration is a microresonator structure called a microcavity structure, it is necessary to change the thickness of the hole transport layer 4 for each pixel. Therefore, only the organic layer 3 (hole injection layer 3) is formed on the entire surface covering the first electrode 2, a partition wall 5 is provided on the organic layer 3, and a thickness is formed in the opening 10 formed by the partition wall 5. The hole transport layers 4R, 4G, and 4B having different sizes are formed for each pixel, and the light emitting layer 6 is formed on the hole transport layers 4R, 4G, and 4B in the opening 10 to form a microcavity structure. In such a case, a predetermined amount of the organic material ink for the hole transport layer is applied to each opening so that the hole transport layers 4R, 4G, and 4B have a thickness required for each pixel, and then dried. Then, the hole transport layers 4R, 4G, and 4B having a predetermined thickness are formed. Subsequently, the light emitting layer 6 is formed using the organic material ink for the light emitting layer.

  In this microcavity structure, for example, in the example of FIG. 7, the first electrode 2 (anode) is a total reflection electrode, the second electrode (cathode) for extracting light is a translucent electrode of a dielectric mirror, and an organic layer When the thickness (thickness including the hole transport layer 4 and the light emitting layer 6) is adjusted to the wavelength required for each light of RGB and set to have different thicknesses, the light emitted from the light emitting layer 6 The light component having the shifted wavelength resonates by repeating multiple reflections between the anode and the cathode. Then, it is enhanced to the wavelength of the light to be extracted and jumps out from the cathode side.

  The size of the raised portion in the vicinity of the partition wall 5 (reference numeral 12 in FIG. 2) differs depending on the viscosity of the organic material ink 6 ′ to be applied, and cannot be generally stated. However, when the viscosity is small, the width of the raised portion 12 is generally obtained. When the viscosity is small and the viscosity is large, the width of the raised portion 12 is generally increased. Since the flat part area | region a expands, so that the width | variety of the raised part 12 is small, it becomes possible to expand the flat part area | region a more by adjusting viscosity. In addition, the preferable viscosity which measured the organic material ink with the cone-and-plate type viscometer is 1 mPa · s to 50 mPa · s.

  The coating type organic material ink for forming the light emitting layer 6 (in the case of FIG. 7, the hole transport layer 4 and the light emitting layer 6) can include various types and is not particularly limited. In the present invention, such an organic material ink is applied to a printing method, an inkjet method (droplet ejection method), a nozzle printing method (liquid column ejection method), a dispensing method, a spin coating method, a casting method, a dip coating method, a bar coating method, Coating can be performed using a wet coating method such as a blade coating method, a roll coating method, a gravure coating method, a flexographic printing method, or a spray coating method.

  The organic material ink after application is volatilized by drying to form an organic layer having a predetermined thickness. The thickness of the organic layer differs depending on whether the organic layer is the light emitting layer 6 of the embodiment shown in FIG. 2, the hole transport layer 4 and the light emitting layer 6 constituting the microcavity structure shown in FIG. Therefore, the organic material ink is applied so as to have a thickness suitable for each layer.

  The organic material ink for forming each organic layer is not particularly limited as long as it is a coating type organic material ink, and various types can be used.

  Examples of the solvent include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; alcohols such as methanol, ethanol, 2-propanol, n-butanol, and 2-ethoxyethanol; benzene, toluene, xylene, mesitylene, p -Aromatic hydrocarbons such as cymene and diisopropylbenzene; Esters such as ethyl acetate, isobutyl acetate, butyl acetate and methyl propionate; diethyl ether, diisopropyl ether, tert-butyl methyl ether, cyclopentyl methyl ether, dimethoxyethane, ethylene Ethers such as glycol diethyl ether, tetrahydrofuran, 1,4-dioxane; pentane, hexane, heptane, octane, decane, dodecane, undecane, cyclohexane Sun, aliphatic hydrocarbons decalin; dichloromethane, 1,2-dichloroethane, chloroform, o- halogenated aromatic hydrocarbons dichlorobenzene, and the like.

  Examples of the light emitting layer ink 6 'include light emitting material-containing inks such as pigment material ink, metal complex material ink, and polymer material ink. These materials may be used alone or in combination of two or more.

  Examples of dye-based material inks include cyclopentadiene derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, arylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylpyrazine derivatives, distyryl ants. Lane derivative, silole derivative, carbazole derivative, anthracene derivative, dinaphthylanthracene derivative, phenylanthracene derivative, thiophene ring compound, pyridine ring compound, perinone derivative, perylene derivative, oligothiophene derivative, trifumanylamine derivative, coumarin derivative, oxadiazole Dimer, pyrazoline dimer, phenanthroline, etc. can be mentioned. Moreover, the compound which introduce | transduced the fluorene group and the spiro group into these can also be used. These materials may be used alone or in combination of two or more.

  Examples of the metal complex material ink include, for example, Al, Zn, Be, Ir, Pt, or the like as a central metal, or rare earth metals such as Tb, Eu, Dy, and the like, and oxadiazole, thiadiazole, phenyl as a ligand. A metal complex having a pyridine, phenylbenzimidazole, quinoline structure, or the like can be given. Examples of the metal complex include an aluminum quinolinol complex, a benzoquinolinol beryllium complex, a benzoxazole zinc complex, a benzothiazole zinc complex, an azomethylzinc complex, a porphyrin zinc complex, a europium complex, an iridium metal complex, and a platinum metal complex. These materials may be used alone or in combination of two or more.

  Examples of polymer material inks include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyvinylcarbazole, polyfluorenone derivatives, polyfluorene derivatives, polyquinoxaline derivatives, polydialkylfluorene derivatives, And copolymers thereof. Moreover, what polymerized the said pigment-type luminescent material and metal complex type | system | group luminescent material is also mentioned.

  In such a light emitting layer ink, a fluorescent light emitting or phosphorescent light emitting dopant may be added. Examples of such dopants include perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squalium derivatives, porphyrin derivatives, styryl dyes, tetracene derivatives, pyrazoline derivatives, decacyclene, phenoxazone, quinoxaline derivatives, carbazole derivatives, fluorene derivatives, and the like. Can be mentioned.

  In the case where the hole transport layer 4 constituting the microcavity structure shown in FIG. 7 is formed in the opening 10 before the formation of the light emitting layer 6, the arylamine described in “Organic layer formation step 1”. A hole transport layer material such as a derivative, anthracene derivative, carbazole derivative, thiophene derivative, fluorene derivative, distyrylbenzene derivative, or spiro compound can be used.

  As described above, in the organic layer forming step, the light emitting layer 6 (FIG. 7) is used by using the coating type light emitting layer ink 6 ′ (in the case of FIG. 7, the hole transport layer ink and the light emitting layer ink). In this case, a hole transport layer and a light emitting layer) are formed. However, the present invention is not limited to these examples, and can be applied to various modes. For example, a layer formed of a coating-type organic material ink may include a subsequent electron transport layer.

  Further, the structure of the organic EL layer can be in various modes depending on the material used. For example, the above-described five-layer type (hole injection layer 3, hole transport layer 4, light emitting layer 6, electron transport layer 7, Other than the electron injection layer 8), for example, when the hole transport layer and the light emitting layer are integrated, the electron transport layer and the electron injection layer may be integrated. In addition, an optional layer may be omitted from the organic EL layer having a five-layer structure as necessary, and holes or electrons can be prevented from penetrating like a hole blocking layer or an electron blocking layer. Further, a layer added to prevent exciton diffusion and confine excitons in the light emitting layer to increase recombination efficiency may be added.

(Organic layer forming step 3)
Next, as shown in FIG. 4F, when there is a part of the organic EL layer 11 to be formed, such a layer is formed. In this embodiment, the electron transport layer 7 and the electron injection layer 8 are formed on the light emitting layer 6.

  The electron transport layer 7 and the electron injection layer 8 are formed by a dry method such as a vacuum deposition method. Each of the layers 7 and 8 may be sequentially patterned by mask vapor deposition, or may be patterned by patterning after being laminated on the entire surface as shown in FIGS.

  Examples of the material for the electron transport layer include oxadiazoles, triazoles, phenanthrolines, silole derivatives, cyclopentadiene derivatives, aluminum complexes, and the like.

  Examples of the material for the electron injection layer include alkali metals or alkaline earth metals such as strontium, calcium, lithium, cesium, etc .; oxides of alkali metals or alkaline earth metals such as magnesium oxide, strontium oxide, and lithium oxide ; Fluoride of alkali metal or alkaline earth metal such as lithium fluoride, magnesium fluoride, strontium fluoride, calcium fluoride, barium fluoride, cesium fluoride; organic of alkali metal such as polymethylmethacrylate polystyrene sodium sulfonate A complex etc. can be mentioned.

  The layers thus formed (the electron transport layer 7 and the electron injection layer 8) are provided on the opening 10 and the partition wall 5 where the light emitting layer 6 is the outermost surface. Since the first electrode 2 is covered with the hole injection layer 3 and the hole transport layer 4, there is no gap that may contact and short-circuit the first electrode 2, and therefore the first electrode 2. There can be no short circuit between.

(Second electrode forming step)
Next, as shown in FIG. 4H, the second electrode 9 is formed on the organic EL layer 11. As described above, the second electrode 9 may be selectively formed in a predetermined pattern on the patterned organic EL layer 11 by mask vapor deposition or the like, or may be formed on the entire surface of the patterned organic EL layer 11. It is good also as a predetermined pattern by patterning after forming.

  In the case of the passive matrix system shown in FIG. 1A, the second electrode 9 is formed in a strip or stripe pattern orthogonal to the extending direction of the strip or stripe first electrode 2, The intersection is a pixel in the passive matrix system. On the other hand, in the case of the active matrix system shown in FIG. 1 (B), the second electrode 9 is usually formed on the entire surface as a counter electrode of the first electrode 2 corresponding to each pixel.

  Examples of the method for forming the second electrode 9 include physical vapor deposition methods such as chemical vapor deposition, vacuum deposition, sputtering, and ion plating.

  As the cathode material that is the second electrode 9, in the case of a top emission structure or a transparent display, In—Sn—O (ITO), In—Zn—O (IZO), Zn—O, Zn—O—Al, Examples thereof include transparent conductive oxides such as Zn—Sn—O. In the case of a bottom emission structure, examples include metals such as aluminum, gold, silver, nickel, palladium, and platinum.

(Other processes)
After the second electrode 9 is formed, for example, a sealing material may be provided as necessary, or a transparent base material may be provided via the sealing material. In this case, the sealing material can include an epoxy resin. Further, as the transparent substrate, among the above-described substrate 1, particularly highly transparent glass, polyethersulfone (PES), polyethylene terephthalate (PET), or the like can be used.

  As described above, the number of organic layers applied and formed in the opening 10 is reduced by going through the procedure of the method for manufacturing an organic EL element of the present invention. 2 to 4, only the light emitting layer 6 is applied separately for each pixel, and the hole transport layer 4 and the light emitting layer 6 are also used in the example of FIG. 7. Therefore, the process is simplified and simplified, and the tact is improved, and the fluid organic material ink applied in the opening 10 has a conventional manner in which the ink meniscus and the ink spread spread (FIG. 9). (See FIG. 2), the flatness of the organic layer 6 applied and formed in the opening 10 that is the pixel region is increased, and the flat portion region a (see FIG. 2) is formed so that luminance unevenness and light emission color unevenness do not occur. ) Can be expanded to the vicinity of the partition wall 5. As a result, display unevenness such as luminance unevenness and light emission color unevenness when the organic EL layer 11 emits light can be suppressed. Further, since the partition walls 5 having a predetermined pattern are directly formed on the organic layer 4 by a drawing method, there is no problem (damage to the organic layer due to a developer or an etching solution) as in the case of applying a photolithography method, and the low A partition can be formed on an organic layer made of an organic material containing a molecular compound or an inorganic compound.

[Light-emitting display device]
In the light-emitting display device of the present invention, the organic EL element according to the present invention can be used as a passive matrix type or active matrix type EL panel.

  Specifically, the organic EL element illustrated in FIG. 1A is an example of an EL panel applied to a passive matrix light-emitting display device, and the opening 10A included in the organic EL element is unidirectional (FIG. 1A ) In the Y direction). In the case of this passive matrix system, the second electrode 9 is formed in a strip or stripe pattern orthogonal to the extending direction of the strip-shaped or strip-shaped first electrode 2, and the intersecting portion is formed in the passive matrix system. It becomes a pixel.

  On the other hand, the organic EL element shown in FIG. 1B is an example of an EL panel applied to an active matrix light emitting display device, and each opening 10B included in the organic EL element constitutes an individual unit pixel. Yes. In the case of this active matrix system, the second electrode 9 is normally formed on the entire surface as a counter electrode of the first electrode 2 corresponding to each pixel. 1B, the first electrode 2, the organic EL layer 11 and the second electrode 9 are provided on the TFT substrate 1b, and the first electrode 2 is formed on the TFT substrate 1b. The wiring 32 is connected to the TFT 32 through the wiring via 31.

  Such a TFT 32 only needs to be composed of at least a gate electrode, an insulating layer (including a gate insulating film), a semiconductor film, a source electrode, and a drain electrode. Any structure of a bottom contact structure, a top gate / top contact structure, and a top gate / bottom contact structure may be used. Note that the semiconductor film may be an organic semiconductor film or an inorganic semiconductor film. In the TFT substrate 1b, a gate bus line of the gate electrode and a source bus line of the source electrode extend in the vertical and horizontal directions. An output element is connected to the drain electrode of each TFT 32, and the output element is the organic EL element of the present invention.

  Such a light emitting display device can be applied to either a passive matrix organic EL element or an active matrix organic EL element, and can provide an image in which display unevenness is suppressed in any case.

  Hereinafter, the organic EL device of the present invention will be described more specifically with reference to Examples and Comparative Examples.

[Example 1]
(1) A glass substrate 1 having a thickness of 0.7 mm on which a first electrode pattern corresponding to a passive matrix pixel was formed was prepared. The first electrode 2 has a stripe shape with a width of 100 μm extending in one direction, and is made of an ITO film having a width W1 of a gap G between adjacent electrodes of 30 μm and a thickness of 0.2 μm.

  (2) Next, a solution in which a molybdenum hexacarbonyl complex, which is a metal complex compound, was converted into an ink with ethyl benzoate was discharged from the inkjet head over the entire surface covering the first electrode 2. Thereafter, the substrate coated with the molybdenum hexacarbonyl complex, which is a metal complex compound, was heated in the atmosphere at 200 ° C. for 60 minutes. Thereby, the solvent in the liquid was volatilized, and the hole injection layer 3 having a thickness of 15 nm was formed.

  (3) Next, poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (4,4), which is a conjugated polymer material, is formed on the entire surface of the hole injection layer 3. '-(N- (4-sec-butylphenyl)) diphenylamine)] (TFB) and 2-methyl-9,10 bis (naphthalen-2-yl) anthracene (MADN), which is a low molecular weight compound, benzoic acid Ink dissolved in ethyl was ejected from the inkjet head. After heating at 200 ° C. for 1 minute in the atmosphere and waiting for the solvent to evaporate, it was heated at 200 ° C. for 1 hour in a glove box. Thereby, the hole transport layer 4 having a thickness of 30 nm was formed.

  (4) Next, the partition wall 5 having a width W2 of 30 μm was formed by the direct drawing method above the gap G between the first electrode patterns and on the hole transport layer 4. At this time, the center of the width W2 of the partition wall 5 was made to coincide with the center of the width W1 of the gap G. The partition wall 5 was formed with a thickness of 5 μm by directly drawing by a screen printing method using a material made of an acrylate resin containing a fluorine-based additive. The opening 10 defined by the partition 5 constitutes a pixel having a width of 100 μm and extending in one direction.

  (5) Next, 1-tert-butyl-perylene (TBP) is contained as a light emitting dopant as a light emitting layer, and 2-methyl-9,10 bis (naphthalen-2-yl) anthracene (MADN) is contained as a host. A prepared ethyl benzoate solution was prepared and discharged from the inkjet head into the opening 10. After heating at 200 ° C. for 1 minute in the atmosphere and waiting for the solvent to evaporate, it was heated in a glove box at 130 ° C. for 1 hour. Thereby, the light emitting layer 6 having a thickness of 40 nm was formed in the opening 10.

  (6) After forming these three layers (hole injection layer 3, hole transport layer 4, and light emitting layer 6), the film thickness from the surface of the substrate 1 was measured. In the cross section including the central portion of the light emitting layer 6 in the pixel, the width of the light emitting layer 6 was 100 μm, and the width of the flat region a (see FIG. 2) was 80 μm. The film thickness was measured by a scanning white interference method, and the flat region was within a range of ± 10% of the center film thickness.

  (7) Next, Alq3 is 20 nm thick as the electron transport layer 7 and LiF is 0.5 nm thick as the electron injection layer 8 so as to cover the partition wall 5 and the light emitting layer 6, and laminated by vacuum heating evaporation. A film was formed.

  (8) Next, a 250-nm-thick Al film is formed on the entire surface by vacuum heating evaporation, and then formed into a stripe shape having a width of 130 μm so as to be orthogonal to the direction in which the stripe-shaped first electrode 2 extends. Patterning was performed to form a second electrode pattern. Subsequently, an epoxy resin was applied as a sealing material, a glass substrate was placed thereon, and the epoxy resin was cured by irradiating ultraviolet rays to perform sealing.

  (9) Thus, an organic EL element to be a passive matrix type EL panel was produced. In the obtained organic EL element, the width of the flat region a with respect to the first electrode 2 having a width of 100 μm was 80 μm, and the flat region was formed with a high area ratio of 80%.

[Example 2]
A substrate 1 including a 0.7 mm thick TFT substrate 1b on which a first electrode pattern corresponding to an active matrix pixel was formed was prepared. The first electrode 2 corresponds to each pixel of the active matrix system, and is a square pattern having a length of 100 μm and a width of 100 μm. A width W1 of a gap G between adjacent electrodes vertically and horizontally is 30 μm and a thickness of 0.1 μm. It consists of a 2 μm ITO film. The substrate 1 including the TFT substrate 1 b is in the form shown in FIG. 1B, and the first electrode 2 is connected to the TFT 32 through the wiring via 31.

  A partition wall 5 having a width W2 of 30 μm was formed by direct drawing on the hole transport layer 4 above the gap G of the first electrode pattern corresponding to each pixel of the active matrix system. At this time, the center of the width W2 of the partition wall 5 was made to coincide with the center of the width W1 of the gap G. The partition wall 5 was formed with a thickness of 5 μm by directly drawing by a screen printing method using a material made of an acrylate resin containing a fluorine-based additive. The opening 10 defined by the partition 5 constitutes a pixel having a width of 100 μm and extending in one direction.

  The other steps, that is, the steps of forming the hole injection layer 3, the hole transport layer 4, the light emitting layer 6, the electron transport layer 7 and the electron injection layer 8 are the same as those in the first embodiment.

  Next, a second electrode 9 was formed by forming a 250 nm thick Al film on the entire surface by vacuum heating vapor deposition. Subsequently, an epoxy resin was applied as a sealing material, a glass substrate was placed thereon, and the epoxy resin was cured by irradiating ultraviolet rays to perform sealing.

  Thus, an organic EL element to be an active matrix type EL panel was produced. In the obtained organic EL device, the flat portion region a with respect to the first electrode 2 having a length of 100 μm and a width of 100 μm was 80 μm and a width of 80 μm, and the flat portion region could be formed with a high area ratio of 80%.

[Examples 3 and 4]
An organic EL device in which a low molecular compound was replaced was produced. As the hole transport layer 4, poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (4,4 ′-(N- (4-sec- Butylphenyl)) diphenylamine)] (TFB) and low molecular weight compounds 2- (4-biphenylyl) -5- (4-tert-butyl-phenyl) -1,3,4-oxadiazole (PBD) As a light-emitting layer 6, 2- (4-biphenylyl) -5- (4-tert-butyl-phenyl) -1,3,4-oxadiazole (PBD) and 1-tert-butyl- A mixture with perylene (TBP) was used. Other than that was carried out similarly to Example 1, 2, and produced the organic EL element of Example 3, 4. Similar to Examples 1 and 2, the flat region was formed with a high area ratio.

  In the production of the organic EL elements of Examples 3 and 4, the partition wall 5 was formed by the same direct drawing method (screen printing method) as in Examples 1 and 2, but it was included in the ink in the examination process. It was found that there is a suitable drawing method depending on the content ratio of the low molecular compound or the inorganic compound. For example, when the content ratio of the low molecular compound or inorganic compound is 50% by weight or less, a wet drawing method such as screen printing is suitable, but when it exceeds 50% by weight, a dry drawing method such as a laser transfer method is suitable. all right. The reason for this was presumed that when the solvent in the ink volatilizes, the film re-dissolves and adversely affects the film quality.

[Example 5]
An organic EL element in which the partition walls 5 were formed by a laser transfer method was produced. An acrylate resin containing carbon black as a pigment is formed as a photothermal conversion layer on a PET film, and an acrylate resin containing Modiper F, which is a fluorine component, is laminated thereon as a liquid-repellent partition layer to obtain a donor sheet. . Next, in the same manner as in Example 1, a hole transport layer 4 is formed on the glass substrate 1 and is adhered so that the liquid repellent partition layer is in contact with the hole transport layer 4. A semiconductor laser was irradiated from the film side with an output of 170 mW. When the donor sheet was peeled off after irradiation, it was confirmed that only the portion irradiated with the laser was transferred onto the hole transport layer 4. Thereafter, the light emitting layer 6 and subsequent layers were formed in the same manner as in Example 1 to produce the organic EL device of Example 5. Similar to Examples 1 and 2, the flat region was formed with a high area ratio.

[Comparative Example 1]
As shown in FIG. 9, an insulating film 105 and a partition wall 106 functioning as a partition wall are formed so as to span a gap in the pattern of the first electrode 102, and hole injection is performed in an opening 110 surrounded by the partition wall 106. The layer 104, the hole transport layer 107, and the light emitting layer 108 were formed in that order by ink application, and the organic EL device of Comparative Example 1 was produced. In the obtained organic EL element, the width of the flat region a ′ with respect to the first electrode 102 having a width of 100 μm was 60 μm, and the area ratio of the flat region was 60%.

[Comparative Example 2]
An organic EL element in which the partition walls 5 were formed by photolithography was produced. The process was the same as in Example 1 until the hole transport layer 4 was formed, and then a positive photoresist was applied to the entire surface. By exposing and developing through a photomask on which a desired pattern is drawn, a barrier rib pattern of a photoresist was formed on the hole transport layer 4. A light emitting layer 6, an electron transport layer 7, an electron injection layer 8, and a second electrode 9 were formed in the opening 10 in the formed partition wall in the same manner as in Example 1 to produce an organic EL device. When a voltage of 10 V was applied with a DC power source and the light emitting part was confirmed, many non-light emitting parts and light emission unevenness were confirmed in the light emitting part. The light emission unevenness was thought to be due to the fact that the low molecular components of the hole transport material were partially removed during photoresist development, resulting in unevenness in the film structure in the opening.

[Evaluation of display unevenness]
About the organic EL element produced in Example 1 and Comparative Example 1, both DC voltage was applied 8V each, and the light-emitting area was measured with the two-dimensional color luminance meter (Konica Minolta company make: CA-2000). As a result of the measurement, a region substantially equivalent to the flat portion region a having a film thickness emitted light, and light emission was hardly confirmed in other thick film regions (a portion other than the flat portion region and a raised portion on the partition wall side). . For these reasons, the organic EL element of Example 1 achieved about 80% light emission region, while the organic EL element of Comparative Example 1 only emitted light of 60%.

DESCRIPTION OF SYMBOLS 1 Substrate 1a Base substrate 1b TFT substrate 2 1st electrode 3 Hole injection layer 4 Hole transport layer 5 Partition 6 Light emitting layer 6 'Light emitting layer ink 7 Electron transport layer 8 Electron injection layer 9 Second electrode 10, 10A, 10B Opening portion 11 Organic EL layer 12 Swelling portion on partition side 15 Upper surface of partition wall 16 Insulating layer 17 Formed surface 18 Center of width of partition wall 19 Edge of first electrode (edge)
31 Via 32 TFT

G Gap W1 Gap width W2 Bulkhead width W3 Recessed width of the bulkhead when the width of the bulkhead is smaller than the width of the gap between the first electrodes W4 When the width of the bulkhead is larger than the width of the gap between the first electrodes Separation width of bulkhead H Height (thickness) of bulkhead
a Flat area

101 Substrate 102 First electrode 103 Edge of first electrode 104 Organic layer (hole injection layer)
DESCRIPTION OF SYMBOLS 105 Insulating film 106 Partition 107 Hole transport layer 108 Light emitting layer 110 Opening part 111 The rising part by the side of a partition 112 Center part a 'Flat part area | region

Claims (9)

Preparing a substrate having a first electrode formed in a pattern corresponding to a pixel;
Forming an organic layer including at least a hole injection functional layer on an entire surface covering the first electrode with an organic material including a low molecular compound or an inorganic compound;
Forming a partition having a predetermined pattern on the organic layer by a direct drawing method to form an opening corresponding to the pixel;
Applying an organic material constituting a part or all of the organic EL layer excluding the organic layer into the opening surrounded by the partition wall to form an organic layer;
And a step of forming a second electrode on the organic EL layer. A method for producing an organic electroluminescent element, comprising:   The organic layer including at least the hole injection functional layer is selected from a hole injection layer, a hole injection transport layer, and a laminate of a hole injection layer and a hole transport layer. Manufacturing method of organic electroluminescent element.   The low molecular compound is selected from arylamine derivatives, porphyrin derivatives, carbazole derivatives, anthracene derivatives, phthalocyanine compounds and thiophene derivatives, and the inorganic compound is a metal oxide or metal complex of vanadium, molybdenum, ruthenium, aluminum and titanium. The manufacturing method of the organic electroluminescent element of Claim 1 or 2 chosen from a compound.   The method for producing an organic electroluminescence element according to claim 1, wherein the direct drawing method is selected from a printing method, a transfer method, a droplet discharge method, and a liquid column discharge method.   The manufacturing method of the organic electroluminescent element of any one of Claims 1-4 whose application | coating of the said organic material is a droplet discharge method and a liquid injection discharge method. A substrate,
A first electrode formed in a pattern corresponding to a pixel on the substrate;
An organic layer including at least a hole injection functional layer formed on the entire surface covering the first electrode;
A partition for forming an opening corresponding to the pixel on the organic layer;
An organic EL layer in which an organic layer other than the organic layer constituting part or all of the organic EL layer is formed in the opening surrounded by the partition;
An organic electroluminescence element comprising at least a second electrode formed on the organic EL layer.   The organic layer including at least the hole injection functional layer is selected from a hole injection layer, a hole injection transport layer, and a laminate of a hole injection layer and a hole transport layer. Organic electroluminescence device.   The low molecular compound is selected from arylamine derivatives, porphyrin derivatives, carbazole derivatives, anthracene derivatives, phthalocyanine compounds and thiophene derivatives, and the inorganic compound is a metal oxide or metal complex of vanadium, molybdenum, ruthenium, aluminum and titanium. The organic electroluminescence device according to claim 6 or 7, which is selected from compounds.   A light-emitting display device using the organic electroluminescent element according to claim 6 as an EL panel of a passive matrix type or an active matrix type.

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