Organic el display device, and method for manufacturing same

Abstract

The objective of the present invention is to provide an organic EL display device and a method for manufacturing the same, with which the manufacture of the organic EL display device, including formation of a pixel dividing layer and a spacer, can be performed using a simple method, and with which the organic EL display device has a high reliability as a flexible display device and is capable of suppressing external light reflection.　As a means for overcoming the problem, the organic EL display device comprises a board including a first electrode, a pixel dividing layer, and a spacer, on a substrate, and an organic EL layer and a second electrode, wherein, if Ramax is the maximum value of a surface roughness (Ra1) of the pixel dividing layer and a surface roughness (Ra2) of the spacer, Ramax is 1.0 nm to 50 nm inclusive.

Description

Organic EL display device and manufacturing method thereof

[0001] The present invention relates to an organic EL display device having a plurality of display pixels arranged in a matrix, and a method for manufacturing the same.

[0002] Organic electroluminescence (EL) display devices have been attracting attention as next-generation flat panel displays. Organic EL is the electroluminescence of an organic EL layer made of organic compounds disposed between two electrodes. An OLED display device is a display device that utilizes organic EL light-emitting elements. Self-luminous OLED display devices are capable of wide viewing angles, fast response, and high-contrast image display. By using substrates such as thin glass or plastic resin, they can be made thinner, lighter, and more flexible. Research and development into these devices has been actively pursued in recent years. Flexible OLED display devices are expected to be applied in a variety of fields, including bendable (which can be bent without breaking), rollable (which can be rolled up), and foldable (which can be folded).

[0003] However, such flexible organic EL display devices may cause peeling between the substrate and the organic EL layer due to bending or folding during the manufacturing process or during use, which may result in a decrease in the reliability of the organic EL display device (see, for example, Patent Document 1).

[0004] On the other hand, for mobile devices, it is necessary for the display device to maintain display quality in various environments, both indoors and outdoors. In particular, proposals have been made to suppress external light reflection, such as combining the display device with a circular polarizing plate or blackening the substrate (see, for example, Patent Document 2).

[0005] JP 2020-87935 A JP 2004-281365 A

[0006] However, in the organic EL display device described in Patent Document 1, in which inverted tapered spacers are provided on the pixel division layer to prevent peeling for flexibility, it is difficult to set the materials and manufacturing conditions due to the characteristics of the spacer shape, and further, the pixel division layer and spacers cannot be processed together, which causes problems such as a decrease in panel yield and a significant increase in costs.

[0007] Furthermore, in the organic EL display device described in Patent Document 2, in which the first electrode and pixel dividing layer are blackened for the purpose of suppressing external light reflection, although some suppression of external light reflection can be expected due to the coloring, the suppression of external light reflection is insufficient due to the smoothness of the reflective surface.

[0008] Therefore, an object of the present invention is to provide an organic EL display device that can be manufactured using a simple method, including the formation of pixel dividing layers and spacers, and that is highly reliable as a flexible display device and can suppress external light reflection, as well as a manufacturing method thereof.

[0009] The organic EL display device of the present invention is an organic EL display device having a substrate having a first electrode, a pixel dividing layer, and spacers on a base material, and further having an organic EL layer and a second electrode, wherein when the maximum value of the surface roughness (Ra1) of the pixel dividing layer and the surface roughness (Ra2) of the spacer is defined as Ramax, Ramax is 1.0 nm or more and 50 nm or less.

[0010] Furthermore, the method for manufacturing an organic EL display device of the present invention is a method for manufacturing an organic EL display device having a substrate having a first electrode, a pixel dividing layer, and spacers on a base material, and further having an organic EL layer and a second electrode, and includes a step of processing the pixel dividing layer and the spacers all at once, and the photomask for the processing all at once is a half-tone photomask having a light-transmitting portion, a light-shielding portion, and a semi-light-transmitting portion.

[0011] The organic EL display device of the present invention is manufactured by a simple method, including the formation of a pixel dividing layer and spacers, and does not peel off the organic EL layer. Furthermore, external light reflection can be suppressed by increasing the diffusely reflected light of the substrate.

[0012] FIG. 1 is a schematic cross-sectional view of an organic EL display device according to the present invention; FIG. 2 is a schematic cross-sectional view of a substrate according to an example of the present invention; FIG. 3 is a schematic cross-sectional view of Ra1 and Ra2 according to the present invention; FIG. 4 is a schematic view of a taper angle of a pixel dividing layer according to the present invention; FIG. 5 is a schematic cross-sectional view of a general organic EL display device; FIG. 6 is a schematic view of a first electrode and a half-tone photomask according to an example of the present invention; FIG. 7 is a schematic view of a bending test according to an example of the present invention; FIG. 8 is a schematic view of an organic EL display device according to an example of the present invention;

[0013] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "embodiment") will be described in detail. However, the present invention should not be limited to only the embodiment described below.

[0014] <Organic EL display device> The organic EL display device of the present invention is an organic EL display device having a plurality of display pixels arranged in a matrix. Depending on the direction of extraction of light emitted from the organic EL layer, they are roughly classified into top emission and bottom emission, but are not particularly limited thereto. Depending on the driving method, they are roughly classified into passive driving types, in which electrodes are divided into columns and rows and only the display pixels sandwiched between the electrodes are made to emit light, and active driving types, in which several TFTs are provided for each display pixel and switched, but are not particularly limited thereto.

[0015] The organic EL display device of the present invention is an organic EL display device that includes a substrate having a first electrode, a pixel dividing layer, and spacers on a base material, and further includes an organic EL layer and a second electrode, and when the maximum value of the surface roughness (Ra1) of the pixel dividing layer and the surface roughness (Ra2) of the spacer is defined as Ramax, the organic EL display device has Ramax of 1.0 nm or more and 50 nm or less.

[0016] Figure 1 shows a schematic cross-sectional view of an organic EL display device according to an example of the present invention. In this organic EL display device, a first electrode 2 is provided on a substrate 1. A pixel dividing layer 3 is provided on the substrate 1 in an area where the first electrode 2 is not present (hereinafter, the area on the substrate 1 where the first electrode 2 is not present may be referred to as a first electrode gap), and spacers 4 are provided on the pixel dividing layer. In this organic EL display device, the unit comprising the first electrode, pixel dividing layer, and spacers on the substrate is referred to as a substrate. Furthermore, an organic EL layer 5 and a second electrode 6 are provided on the substrate to form an organic EL display device.

[0017] <Substrate> In the organic EL display device of the present invention, the substrate is defined as a minimum unit consisting of only the substrate 1, first electrode 2, pixel dividing layer 3, and spacer 4 described below. As long as the substrate has such a minimum unit, it may further include wiring, TFT 7, a pattern antenna, a planarization layer 8, and the like (for example, the configuration shown in FIG. 2 ). However, in the present invention, the above-mentioned wiring, TFT 7, sensors, pattern antenna, and the like, as well as the planarization layer 8, which form the base of the first electrode 2, are all considered to be part of the substrate 1.

[0018] The wiring is often connected to external devices via a flexible printed circuit (FPC) for driving. In addition to the TFTs 7, sensors such as a camera, sensors for ID and fingerprint reading and illuminance, and pattern antennas for communication and power supply may also be provided. In the substrate 1 integrating multiple functions in this manner, it is preferable to provide a planarization layer 8. By providing the planarization layer 8, unevenness of the wiring and TFTs 7 can be covered before the formation of the first electrodes 2, thereby planarizing the substrate 1. Planarizing the substrate 1 prevents defects in the first electrodes 2, pixel dividing layers 3, and spacers 4 provided on the substrate, resulting in a high-quality substrate. Figure 2 shows a schematic cross-sectional view of an example substrate of the present invention.

[0019] 1 and the base 1a of the substrate below the TFT 7 of the substrate 1 in FIG. 2 can be appropriately selected from metal, glass, resin film, etc., which are suitable for supporting the display device and transporting in subsequent processes. In particular, when flexibility is required, a resin film is preferable.

[0020] As the glass, soda lime glass, alkali-free glass, etc. can be used. The thickness of the glass is sufficient as long as it is thick enough to maintain mechanical strength. As for the glass material, alkali-free glass is preferable because it is better to have fewer ions eluted from the glass. However, SiO ２ It is also possible to use soda lime glass coated with a barrier coating such as

[0021] The resin film material is preferably a resin material selected from polybenzoxazole resin, polyamideimide resin, polyimide resin, polyamide resin, and poly(p-xylylene) resin, because of its excellent light transmittance. The substrate may contain these resin materials alone or in combination.

[0022] For example, when forming the substrate from a polyimide resin, it can be formed by applying a solution containing a polyamic acid resin (including a partially imidized polyamic acid) which is a precursor of the polyimide resin, or a soluble polyimide resin, to a support substrate and baking it.

[0023] Furthermore, since the light-emitting elements described above are known to be vulnerable to oxygen and moisture, a gas barrier layer may be provided as an appropriate component of the substrate. In particular, in the case of a resin film, a highly reliable display device can be obtained by laminating an inorganic thin film thereon. Furthermore, the substrate may be provided with wiring, a TFT 7, a planarization layer 8, etc.

[0024] <First Electrode> The first electrode 2 in the present invention must be a light-transmitting electrode in the case of a bottom emission type, and a light-reflective electrode in the case of a top emission type.

[0025] For a bottom emission type, for example, conductive metal oxides such as transparent tin oxide, indium oxide, and indium tin oxide (ITO), metals such as gold, silver, and chromium, inorganic conductive substances such as copper iodide and copper sulfide, and conductive polymers such as polythiophene, polypyrrole, and polyaniline can be used, but are not particularly limited thereto.

[0026] For top-emission devices, materials that exhibit high visible light reflectivity and low electrical resistance above a certain film thickness are preferred. Furthermore, material selection is also necessary in terms of subsequent wet etching and cleaning processes, as well as weather resistance in storage and usage environments. Ag or Ag alloy films containing Ag as the primary component are particularly useful due to their high reflectivity. Ag alloy films can be made of AgPdCu or AgTiCu, which contain Ag as the primary component. Laminating these Ag alloy films with conductive oxide films such as ITO or IZO is preferred because it achieves low contact resistance with the organic EL layer. Furthermore, Al or Al alloy films containing Al as the primary component are also suitable for use as top-emission first electrodes. Al-Ni alloy films containing 0.1 to 2 atomic % Ni are preferred because they have a high reflectivity comparable to that of pure Al. Reflective metal films such as molybdenum (Mo) and tungsten (W) can also be used.

[0027] The resistance of the first electrode is not limited as long as it can supply a sufficient current for the light-emitting element to emit light, but a low resistance is desirable from the perspective of the power consumption of the light-emitting element. For example, ITO of 300 Ω / □ or less can function as an element electrode, but since ITO of about 10 Ω / □ is now available, it is particularly desirable to use a low-resistance product. The thickness of the first electrode can be selected arbitrarily depending on characteristics such as transmittance and resistance value, but can usually be between 100 and 300 nm.

[0028] The first electrode can be formed by a known method, for example, by forming a film by a vacuum film forming method such as sputtering, and then patterning the film by etching using a photoresist.

[0029] <Pixel Division Layer> In the organic EL display device of the present invention, the pixel division layer 3 is formed in the gap of the first electrode 2. By forming the pixel division layer in the gap of the first electrode, the display pixels can be divided. That is, by patterning the pixel division layer in the gap of the first electrode, the exposed portion of the first electrode is limited, and only the opening of the pixel separation layer functions as a display pixel. Furthermore, by having the pixel division layer cover the periphery of the line-type or island-type first electrode, it is possible to prevent short circuits that occur at the edge of the first electrode and breaks in the second electrode, thereby improving the reliability of the display device. Note that in the organic EL display device of the present invention, the pixel division layer may also be formed in places other than the gap of the first electrode, as necessary.

[0030] In the present invention, when the maximum value of the surface roughness (Ra1) of the pixel division layer and the surface roughness (Ra2) of the spacer is defined as Ramax, Ramax is 1.0 nm or more and 50 nm or less. Furthermore, it is more preferable that the surface roughness (Ra1) of the pixel division layer is Ramax. Furthermore, both the surface roughness (Ra1) of the pixel division layer and the surface roughness (Ra2) of the spacer may be Ramax.

[0031] In the present invention, the atomic force microscope (AFM) used to measure surface roughness generally measures the substrate of an organic EL display device placed on a horizontal surface from vertically above, and the target ranges for Ra1 and Ra2 are shown in Fig. 3. Therefore, in the present invention, the "surface roughness of the pixel division layer" refers to the surface roughness of the surface of the pixel division layer that is in contact with the organic EL layer and can be measured by AFM, i.e., the surface roughly parallel to the substrate.

[0032] Furthermore, since spacers are formed on the pixel division layer, the portions without the spacers form the interface that contacts the organic EL layer. Conventionally, poor adhesion between the pixel division layer and the organic EL layer has led to peeling, which has been a major issue, particularly in flexible products. In the present invention, an anchoring effect can be achieved by setting the surface roughness (Ra1) of the pixel division layer to 1.0 nm or more, and preferably 5.0 nm or more, more preferably 20 nm or more, to improve adhesion to the organic EL layer.

[0033] Furthermore, while a surface roughness (Ra1) of 1.0 nm or more of the pixel division layer can provide an anchoring effect, it is preferable to set it to 50 nm or less in order to suppress pinholes in the second electrode and defects in the sealing process described below. Furthermore, when increasing Ra1 to improve adhesion, it is effective to ensure that the interface where the pixel division layer and the organic EL layer contact is as large as possible. When Ra1 is larger than the surface roughness Ra2 of the spacer described below, i.e., when Ra1 is Ramax, it is preferable that the area of ​​the interface where the pixel division layer and the organic EL layer contact is 50% or more of the area of ​​the interface where the substrate and the organic EL layer contact. This means that the pixel division layer accounts for 50% or more of the surface area of ​​the substrate.

[0034] Furthermore, since the shape of the edge of the pixel division layer may cause disconnection of the second electrode, a gentle forward tapered shape is preferable. Here, the forward tapered shape refers to a state in which the angle formed by the tangent at the interface between the first electrode and the pixel division layer and the tangent at a position on the surface of the tapered portion of the pixel division layer at a film thickness that is 50% of the maximum thickness of the pixel division layer (hereinafter, this angle may be referred to as the taper angle of the pixel division layer) is less than 90 degrees. In the present invention, in order to obtain a highly reliable display device in which disconnection of the second electrode is suppressed, the taper angle of the pixel division layer is preferably less than 60 degrees, and more preferably less than 50 degrees.

[0035] The taper angle of the pixel division layer will be specifically described using Fig. 4. In Fig. 4, a first electrode 2 is provided on a substrate 1. A pixel division layer 3 is provided in the gap between the first electrode 2, and spacers 4 are provided on the pixel division layer. The taper angle of the pixel division layer is defined as the angle (B) formed by the tangent to the interface between the first electrode and the pixel division layer and the tangent to a position (point A) on the surface of the tapered portion of the pixel division layer where the film thickness is 50% of the maximum thickness of the pixel division layer.

[0036] The pixel division layer is not limited to either a known organic material or an inorganic material, but it is preferable that the pixel division layer include a cured film of a photosensitive resin composition containing an alkali-soluble resin, because this facilitates adjustment of the surface roughness. The pixel division layer may be a single layer or a multilayer, but for example, when the pixel division layer is a multilayer, it is preferable that the surface approximately parallel to the substrate whose surface roughness is to be measured is a cured film of a photosensitive resin composition containing an alkali-soluble resin.

[0037] The photosensitive resin composition preferably contains (A) an alkali-soluble resin, (B) a photosensitizer, and (C) an organic solvent, and may further contain (D) a coloring material and (E) a liquid-repellent material. By incorporating a combination of (A) an alkali-soluble resin and (B) a photosensitizer into the photosensitive resin composition, pattern processing utilizing photosensitivity becomes possible. Furthermore, by incorporating (C) an organic solvent, the composition can be formed into a varnish, which may improve application properties. Furthermore, by incorporating (D) a coloring material into the photosensitive resin composition, the pixel division layer can be blackened. Furthermore, by incorporating (E) a liquid-repellent material, the pixel division layer can be imparted with liquid-repellent properties. Due to the differences in exposure sensitivity and dissolution rate between the (D) coloring material and (E) liquid-repellent material and the (A) alkali-soluble resin, the surface roughness of the pixel division layer and spacers can be increased and the surface roughness of the pixel division layer and spacers can be adjusted, respectively, in a process using a halftone mask, as described below. The photosensitive resin composition may further contain other components.

[0038] The pixel dividing layer can be formed by any known method. Among them, the wet coating method is preferred because it can form a thin film uniformly on a large substrate. Examples of the wet coating method include spin coating, slit coating, dip coating, spray coating, and printing.

[0039] The thickness of the pixel division layer is usually 0.3 μm to 10 μm, but is not particularly limited as long as it is sufficient to cover the irregularities of the first electrode. Furthermore, the pixel division layer must be patterned, and residues from the removed portions may directly lead to defects such as short circuits and black spots. Furthermore, spacers must be formed on the pixel division layer to support the structure covering the second electrode in a subsequent process and ensure the strength of the display device.

[0040] <(A) Alkali-Soluble Resin> In the present invention, alkali-soluble resin refers to a resin having a dissolution rate of 50 nm / min or more, which is determined from the reduction in film thickness when a solution of the resin in γ-butyrolactone (GBL) is applied to a silicon wafer and prebaked at 120°C for 4 minutes to form a prebaked film having a film thickness of 10 μm±0.5 μm, the prebaked film is immersed in a 2.38 wt % aqueous solution of tetramethylammonium hydroxide at 23°C±1°C for 1 minute, and then rinsed with pure water.

[0041] The alkali-soluble resin (A) preferably has an aromatic carboxylic acid structure in order to improve heat resistance. In the present invention, the aromatic carboxylic acid structure refers to a carboxylic acid structure directly covalently bonded to an aromatic ring.

[0042] The alkali-soluble resin (A) preferably contains one or more resins selected from the group consisting of acrylic resins, phenolic resins, polysiloxane resins, cardo resins, polyimide resins, polyimide precursor resins, polybenzoxazole resins, and polybenzoxazole precursor resins.

[0043] Among these resins, it is preferable that the alkali-soluble resin (A) contains a polyimide resin, a polyimide precursor resin, a polybenzoxazole resin, and / or a polybenzoxazole precursor resin, because it can achieve both heat resistance and chemical resistance. High chemical resistance is preferable because it reduces film loss when processing the pixel dividing layer by wet etching. Furthermore, polyimide precursor resins are particularly preferable because they have a low outgassing amount under high-temperature conditions. Furthermore, polyimide precursor resins having an amide acid structure are more preferable in terms of improving alkali solubility.

[0044] <Silica Particles in Pixel Dividing Layer> The pixel dividing layer in the organic EL display device of the present invention preferably contains (a) silica particles having a primary particle diameter of 5 to 30 nm (hereinafter, sometimes referred to as component (a)). It is more preferable that the pixel dividing layer further contains a coloring material (D) described below in addition to component (a). In such a case, it is even more preferable that the coloring material (D) contains an organic pigment (D1) described below, and it is even more preferable that the organic pigment (D1) contains component (b) described below. Furthermore, it is preferable that component (a) has a primary particle diameter of 5 to 30 nm and an aspect ratio (major axis / minor axis) of 1.0 to 1.5. The inclusion of component (a) improves the uniformity of the opening width of the openings and reduces brightness unevenness. Here, the "primary particle diameter" refers to the major axis of the particles, and silica particles having a primary particle diameter of 5 to 30 nm refer to particles having a primary particle diameter within the range of 5 to 30 nm. The term "aspect ratio (major axis / minor axis)" used herein refers to the value obtained by dividing the major axis by the minor axis in the primary particle diameter of the silica particles, and rounding the result to one decimal place.

[0045] The silica particles referred to here are SiO ２ This refers to particles having a silica content of 90% by weight or more, particles made of silicon dioxide (anhydrous silicic acid), particles made of silicon dioxide hydrate (hydrated silicic acid), and particles made of quartz glass. The form of the hydrated silicic acid is not particularly limited, and particles made of orthosilicic acid, metasilicic acid, and / or metadisilicic acid also fall under the category of silica particles. The weight excluding water refers to the weight of the particle minus the weight of the water in the particle.

[0046] However, in the core-shell type composite particles, the core is SiO ２ The surface treatment agent and coating layer applied as a shell to at least a part of the surface of particles that do not contain SiO, for example, particles made of organic polymers, organic pigments, or inorganic pigments, are ２ Even if it contains SiO ２ On the other hand, when the core contains SiO ２ and SiO２ Core-shell composite particles with a content of 90% by weight or more are defined as silica particles. That is, component (a) is filled as particles in a dispersed state in the pixel dividing layer. The particle structure of component (a) is not particularly limited, and it may have internal voids.

[0047] Examples of silica particles other than the above-mentioned particles made of silicon dioxide, particles made of silicon dioxide hydrate, and particles made of quartz glass include particles containing SiO 2 in a weight excluding water. ２ Examples of the silica particles include silica particles made of a composite oxide of silicon and a metal, in which the content of (a) is 90% by weight or more. Examples of the metal referred to here include zirconium, titanium, and cerium. However, when it comes to silica particles containing hafnium atoms, they are defined as a mixture of silica particles and hafnium atoms (hereinafter, sometimes referred to as component (c)).

[0048] In order to further reduce unevenness in the brightness of organic EL display devices, component (a) preferably contains silica particles having a primary particle diameter of 5 to 20 nm, and even more preferably 5 to 15 nm. The primary particle diameter here refers to the long diameter of the silica particles. It is more preferable that the component contains silica particles having an aspect ratio of 1.0 to 1.3, and even more preferable that the component contains silica particles having an aspect ratio of 1.0 to 1.2. Note that silica particles with an aspect ratio of 1.0 can be considered to be spherical.

[0049] For the (a) component and silica particles other than the (a) component, a thin section of the pixel dividing layer and the spacer layer is used as an observation sample, and the cross section is polished to enhance smoothness by pretreatment, preferably by ion milling, more preferably by focused ion beam (FIB) processing, and a portion located within 0.2 to 0.8 μm in the film depth direction from the outermost layer of the pixel dividing layer or the spacer layer is analyzed by transmission electron microscope-energy dispersive X-ray spectroscopy (TEM-EDX), whereby the elements constituting the particles can be identified from element mapping information. Transmission electron microscope-electron energy loss spectroscopy (TEM-EELS) or scanning transmission electron microscope-energy dispersive X-ray spectroscopy (STEM-EDX) can also be used for analysis.

[0050] Specifically, an image of a sample observed by transmission electron microscope-energy dispersive X-ray spectroscopy (TEM-EDX) at a magnification of 50,000 times is measured using an image analysis particle size distribution analyzer "Mac-View" (manufactured by MOUNTECH), thereby making it possible to distinguish between silica particles corresponding to component (a) and silica particles that do not correspond to component (a). That is, 30 silica particles in the TEM image of the cross section of the pixel dividing layer are randomly selected, and the major axis, minor axis, and aspect ratio in the TEM image of each are measured, and silica particles having a major axis (nm) of 5 to 30 nm and an aspect ratio in the range of 1.0 to 1.5 are defined as component (a). Note that when the minor axis and major axis in the TEM image of a single silica particle are equal, i.e., when the particle is a perfect circle, the diameter is considered to be the major axis. As representative values ​​showing the characteristics of silica particles corresponding to component (a), the average value of primary particle diameter, i.e., the average value of the major axis is calculated and rounded to the nearest tenth, and the average value of aspect ratio, i.e., the average value of the aspect ratio of each silica particle corresponding to component (a) is calculated and rounded to the nearest tenth. Here, SiO 2 having contact points with the surfaces of particles such as particles made of polymer, organic pigment and / or inorganic pigment, etc. ２ The analysis is performed excluding the particles. The major axis and aspect ratio of the silica particles contained in the spacer layer can also be measured in a similar manner.

[0051] The pixel dividing layer of the organic EL display device of the present invention may further contain silica particles that do not fall under component (a), i.e., silica particles having a primary particle diameter of less than 5 nm or more than 30 nm, or silica particles having an aspect ratio (major axis / minor axis) of more than 1.5. Examples of silica particles that do not fall under component (a) include "Admafine" (registered trademark) SO-E2 and SO-E4 (both manufactured by Admatec Co., Ltd.), KE-P10, and KE-S10 (both manufactured by Nippon Shokubai Co., Ltd.).

[0052] The pixel dividing layer of the organic EL display device of the present invention further contains SiO ２In the present specification, particles other than the silica particles may be contained, which contain less than 90% by weight of the silica:polymer ratio. Examples of the particles other than the silica particles include "ATLAS" (registered trademark) 100 (manufactured by CABOT Corporation), which is an organic-inorganic composite particle having a silica:polymer weight ratio of 70:30, as disclosed in JP 2018-97251 A.

[0053] The average primary particle diameter of the silica particles contained in the pixel division layer of the organic EL display device of the present invention is preferably 5 to 30 nm, more preferably 5 to 25 μm, from the viewpoint of suppressing brightness unevenness. The average aspect ratio (major axis / minor axis) is preferably 1.0 to 1.3, more preferably 1.0 to 1.2. That is, even when the pixel division layer of the organic EL display device of the present invention contains silica particles that do not fall under component (a), it is preferable that all of the contained silica particles have an average primary particle diameter of 5 to 30 nm. Similarly, it is also preferable that the average aspect ratio (major axis / minor axis) is 1.0 to 1.3. The silica particles referred to here include both component (a) and silica particles that do not fall under component (a). The average primary particle diameter referred to here is the value obtained by rounding to one decimal place the average value of the major axis of all silica particles obtained by randomly selecting 30 particles from an image of a cross section located in a range of 0.2 to 0.8 μm from the outermost layer of the pixel dividing layer in the film depth direction using the aforementioned transmission electron microscope-energy dispersive X-ray spectroscopy (TEM-EDX) at a magnification of 50,000x, using an image analysis particle size distribution analyzer (Mac-View, manufactured by MOUNTECH). The "average aspect ratio (major axis / minor axis)" referred to here is the value obtained by rounding to one decimal place the average value obtained by dividing the major axis by the minor axis for each of the primary particles of all silica particles obtained at random from the same image of 30 particles. Silica particles having an average primary particle diameter of 5 to 30 nm refer to particles having an average primary particle diameter within the range of 5 to 30 nm, and silica particles having an average aspect ratio of 1.0 to 1.3 refer to particles having an average aspect ratio within the range of 1.0 to 1.3.

[0054] The specific surface area of ​​component (a) corresponding to the above-mentioned primary particle diameter is 50 to 500 m ２ / g is preferred, and 200 to 400m２ / g is more preferable. The specific surface area referred to here is the specific surface area measured by the BET method using nitrogen as the adsorption gas. The surface of component (a) may be porous or non-porous, and may have an internal surface area.

[0055] Examples of functional groups that component (a) has on its surface include reactive residues of surface-modifying groups containing ethylenically unsaturated double bond groups, silanol groups, alkoxysilyl groups, trialkylsilyl groups, and diphenylsilyl groups. Among these, reactive residues of surface-modifying groups containing ethylenically unsaturated double bond groups are preferred for further reducing uneven brightness. The reactive residues of surface-modifying groups containing ethylenically unsaturated double bond groups referred to here refer to groups remaining after the ethylenically unsaturated double bond groups of the surface-modifying groups containing ethylenically unsaturated double bond groups undergo radical polymerization reaction due to light and / or heat. It is more preferred that component (a) contains silica particles having reactive residues of surface-modifying groups containing ethylenically unsaturated double bond groups on their particle surfaces, and that the reactive residues of the surface-modifying groups containing ethylenically unsaturated double bond groups have a structure represented by formula (3) and / or formula (4). The reactive residue of the surface modifying group containing an ethylenically unsaturated double bond group is more preferably a residue generated by a radical polymerization reaction with a compound having two or more radically polymerizable groups in the molecule, as described below.

[0056]

[0057] In formula (3), R １７ １６ represents a hydrogen atom or a methyl group. １８ １７ represents a divalent hydrocarbon group having 1 to 7 carbon atoms. j and k are integers, each independently representing 0 or 1. However, when j is 1, k is 1. １ represents the bonding site with the carbon atom. ２ R represents a bonding site between an oxygen atom bonded to a silicon atom, which is present on the surface of the silica particle. １９ １８ represents an alkyl group having 1 to 3 carbon atoms. m and n are integers, m represents 1 to 3, and n represents 0 to 2, provided that m+n=3 is satisfied.

[0058]

[0059] In formula (4), R ２０ １９ represents a hydrogen atom or a methyl group. ２１ ２０ represents an oxyalkylene group having 1 to 3 carbon atoms. r is an integer of 1 to 4. ３ represents the bonding site with the carbon atom. ４ represents the bonding site between an oxygen atom bonded to a silicon atom, which is present on the surface of a silica particle.

[0060] The component (a) having the structure represented by formula (3) can be obtained by introducing a surface modifying group derived from an organic alkoxysilane compound having an ethylenically unsaturated double bond group through a dehydration condensation reaction with a silanol group on the surface of a silica particle, and then subjecting the ethylenically unsaturated double bond group contained in the surface modifying group to a radical polymerization reaction using light and / or heat.

[0061] Examples of organic alkoxysilane compounds having an ethylenically unsaturated double bond group include vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane, p-styryltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropylmethyldimethoxysilane, 3-acryloxypropylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, allyltrimethoxysilane, and allyltriethoxysilane.

[0062] Component (a), whose reactive residue has a structure represented by formula (4), can be obtained by introducing a surface-modifying group derived from an isocyanate compound having an ethylenically unsaturated double bond group through a urethane reaction with a silanol group on the surface of a silica particle, and then subjecting the ethylenically unsaturated double bond group contained in the surface-modifying group to a radical polymerization reaction using light and / or heat. Examples of the isocyanate compound having an ethylenically unsaturated double bond group include 2-methacryloyloxyethyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-(2-methacryloyloxyethyloxy)ethyl isocyanate.

[0063] Furthermore, by sequentially modifying the surface of silica particles with a surface modifying group derived from an organic alkoxysilane compound having an ethylenically unsaturated double bond group and a surface modifying group derived from an isocyanate compound having an ethylenically unsaturated double bond group, it is possible to obtain component (a) whose reactive residues have a structure represented by formula (3) and a structure represented by formula (4).

[0064] For example, in order to improve the dispersion stability of component (a) in a negative photosensitive composition, component (a) preferably further contains a trialkylsilyl group, more preferably a trimethylsilyl group. The trimethylsilyl group can be introduced into component (a) by converting the hydrogen atoms in the surface silanol groups of the silica particles to trimethylsilyl groups using a trimethylsilylating agent. Examples of trimethylsilylating agents include hexamethyldisilazane and trimethylalkoxysilane, which can be introduced by deammonia reaction and dehydration condensation reaction, respectively. By improving the dispersion stability of component (a), it may be possible to more stably reduce brightness unevenness.

[0065] In order to further reduce brightness unevenness, it is preferable that component (a) contains silica particles having sodium atoms. Examples of the form in which sodium atoms exist include ions (Na+) and salts with silanol groups (Si-ONa). The content of sodium atoms in component (a) is preferably 100 to 5000 ppm by weight. Silica particles having sodium atoms can be synthesized under alkaline conditions by reacting sodium silicate, which is a strongly alkaline silicon source, with a mineral acid, which is a strong acid. Note that the sodium atoms contained in silica particles can be detected in the central region corresponding to the intersection of the major and minor axes in an image of the cross section of the primary particles using the above-mentioned TEM-EDX.

[0066] The content of the component (a) is determined by the amount of SiO in the pixel dividing layer in order to suppress unevenness in brightness. ２ The silica content in the pixel dividing layer is preferably 1 to 50% by weight, more preferably 5 to 20% by weight, calculated from the same viewpoint. ２ The amount is preferably 1 to 50% by weight, more preferably 7 to 30% by weight, calculated as SiO. ２ The converted content means a content calculated based on the common technical knowledge of a person skilled in the art, excluding the weight of water in the silica particles, which varies depending on the thermal history.

[0067] To further reduce unevenness in brightness, the pixel dividing layer in the organic EL display device of the present invention preferably further contains 1 to 50 weight ppm, more preferably 1 to 30 weight ppm, of (c) hafnium atoms (hereinafter sometimes referred to as component (c)). Component (c) is preferably contained in the pixel dividing layer as inorganic particles containing hafnium atoms.

[0068] Examples of inorganic particles containing component (c) include hafnium oxide (HfO ２ ), composite oxides of hafnium and metals other than hafnium, solid solutions of hafnium oxide and oxides of metals other than hafnium, hafnium oxynitride, composite oxynitrides of hafnium and metals other than hafnium, and solid solutions of hafnium oxynitrides and oxynitrides of metals other than hafnium. Among these, hafnium oxide (HfO ２), or a composite oxide of hafnium and a metal other than hafnium, is preferred, and a composite oxide of zirconium and hafnium (ZrO ２ -HfO ２ ) is more preferred.

[0069] As the inorganic particles containing component (c), commercially available products available in powder form can be used, such as Hafnium oxide P, Hafnium oxide R, and Hafnium oxide S (all manufactured by ATI METALS) and hafnium oxide fine particles (manufactured by Kojundo Chemical Laboratory Co., Ltd.). As an alternative method, in the process of preparing a pigment dispersion containing component (b), which will be described later, the surface of a grinding medium containing component (c) is wet-polished using mechanical energy, and the resulting fine particles are co-dispersed with component (b), thereby allowing component (c) to be contained in the pixel division layer finally obtained.

[0070] The content of component (c) can be quantified by ICP (inductively coupled plasma) atomic emission spectroscopy using a sample obtained by scraping off a portion of the pixel dividing layer located within a depth of 0.2 to 0.8 μm from the outermost layer in the film depth direction, heating and incinerating the layer at a temperature of 800°C or higher in an electric furnace, and then thermally decomposing the layer with sulfuric acid, nitric acid, and hydrofluoric acid, followed by heating and dissolving the resulting solution with dilute nitric acid. The analytical device used can be a PS3520VDDII (manufactured by Hitachi High-Tech Science).

[0071] <(D) Coloring Material> When coloring is required from the standpoint of light-blocking properties or anti-reflection, it is preferable that the photosensitive resin composition used in the present invention contains a (D) coloring material. By including a (D) coloring material in the photosensitive resin composition, the pixel dividing layer contains the (D) coloring material, which is preferable because the effects described below can be obtained. The (D) coloring material refers to a compound that absorbs light of a specific wavelength, particularly a compound that colorizes by absorbing light of a visible light wavelength (380 to 780 nm). By including a (D) coloring material, it is possible to color a cured film obtained from the photosensitive resin composition, thereby imparting coloring properties that allow light transmitted through or reflected from the cured film of the photosensitive resin composition to a desired color. Furthermore, it is possible to impart light-blocking properties that block light of a wavelength absorbed by the (D) coloring material from light transmitted through or reflected from the cured film of the photosensitive resin composition.

[0072] The content of the (D) coloring material used in the present invention is preferably 1% by weight or more in the pixel dividing layer, more preferably 10% by weight or more, and even more preferably 15% by weight or more. When the content ratio is within the above range, light-blocking properties, coloring properties, or toning properties can be improved. On the other hand, the content ratio is preferably 70% by weight or less, more preferably 65% ​​by weight or less, and even more preferably 60% by weight or less. When the content ratio is within the above range, sensitivity during exposure can be improved.

[0073] Examples of the (D) coloring material include known compounds such as (D1) organic pigments, (D2) inorganic pigments, and (D3) dyes that absorb light in the visible light wavelength range and color the layer white, red, orange, yellow, green, blue, or purple. Two or more of these coloring materials may be used in combination, or two or more colors may be combined. Combining two or more types is preferred because the resulting pixel division layer possesses the effects described below. Combining two or more colors can improve color-tuning, allowing light transmitted through or reflected from a cured film of the photosensitive resin composition to be toned to the desired color coordinates.

[0074] By using the organic pigment (D1) as the coloring material (D), the organic pigment (D1) has a chemical structure change or functional group conversion function that is characteristic of the organic pigment (D1), and this allows the transmission or absorption spectrum of the cured film of the photosensitive resin composition to be adjusted, for example, to transmit or block light of a desired specific wavelength, thereby improving color toning. Details of such organic pigment (D1) will be described later.

[0075] By using the inorganic pigment (D2) as the coloring material (D), the heat resistance and weather resistance of the cured film of the photosensitive resin composition can be improved due to the excellent heat resistance and weather resistance that are characteristic of the inorganic pigment (D2). Examples of inorganic pigments (D2) include zirconium nitride, zirconium oxide, titanium oxide, barium carbonate, zinc white, zinc sulfide, white lead, calcium carbonate, barium sulfate, white carbon, alumina white, silicon dioxide, kaolin clay, talc, bentonite, red iron oxide, molybdenum red, molybdenum orange, chrome vermilion, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, chromium oxide, viridian, titanium cobalt green, cobalt green, cobalt chrome green, Victoria green, ultramarine, Prussian blue, cobalt blue, cerulean blue, cobalt silica blue, cobalt zinc silica blue, manganese violet, cobalt violet, graphite, and silver-tin alloys; and fine particles, oxides, composite oxides, sulfides, sulfates, nitrates, carbonates, nitrides, carbides, and oxynitrides of metals such as titanium, copper, iron, manganese, cobalt, chromium, nickel, zinc, calcium, and silver.

[0076] Among these, it is preferable to disperse an inorganic pigment with a high specific gravity, such as zirconium nitride, in order to achieve a surface roughness (Ra1) of 1.0 nm or more and 50 nm or less of the pixel division layer. As described below, this is because pigment precipitation during development is expected in the pixel division layer corresponding to the halftone exposed area. Although inorganic pigments have issues such as pigment aggregation, viscosity increase, and sensitivity reduction over time, by setting the acid equivalent of component (A) to 200 g / mol or more and 500 g / mol or less, the alkali solubility of the exposed area, unexposed area, and halftone exposed area, which will be described later, can be favorably adjusted. If the acid equivalent of component (A) is less than 200 g / mol, for example, when obtaining a cured film of the positive photosensitive resin composition, the alkali solubility of the unexposed area is high, the difference in dissolution rate with the exposed area is small, and the desired pattern cannot be formed. By setting the acid equivalent to 200 g / mol or more, the solubility of the unexposed area can be suppressed, making it possible to form a pattern with less residue at the openings due to adhesion of eluate from the unexposed area. Furthermore, by adjusting the acid equivalent of the component (A) to 500 g / mol or less, dispersion stabilization of the zirconium nitride particles is promoted, and a photosensitive resin composition with excellent storage stability can be obtained.

[0077] (D3) Dyes are compounds that color an object by chemically adsorbing or strongly interacting with the surface structure of the object through substituents such as ionic groups or hydroxyl groups in the dye, and are generally soluble in solvents. Furthermore, dye coloring has high coloring power and high color-developing efficiency because each molecule adsorbs to the object. Dyes can be classified into, for example, direct dyes, reactive dyes, sulfur dyes, vat dyes, sulfur dyes, acid dyes, metal-containing dyes, metal-containing acid dyes, basic dyes, mordant dyes, acid mordant dyes, disperse dyes, cationic dyes, and fluorescent brightening dyes. Examples of materials include anthraquinone dyes, azo dyes, azine dyes, phthalocyanine dyes, methine dyes, oxazine dyes, quinoline dyes, indigo dyes, indigoid dyes, carbonium dyes, threne dyes, perinone dyes, perylene dyes, triarylmethane dyes, and xanthene dyes. From the viewpoint of (C) solubility in organic solvents and heat resistance, anthraquinone dyes, azo dyes, azine dyes, methine dyes, triarylmethane dyes, and xanthene dyes are preferred.

[0078] Among these, it is preferable to contain (D3-1) a salt-forming compound consisting of an acid dye and a basic dye as the coloring material (D) in order to set the surface roughness (Ra1) of the pixel division layer to 1.0 nm or more and 50 nm or less. By containing (D3-1) a salt-forming compound consisting of an acid dye and a basic dye, dye precipitation during development is expected in the pixel division layer corresponding to the halftone exposed area.

[0079] (D3-1) The salt-forming compound consisting of an acid dye and a basic dye is a compound obtained by reacting an acid dye with a basic dye. It is a compound obtained by a chemical (salt-forming) reaction between an acid dye whose dye ions are anionic and a basic dye whose dye ions are cationic, and is chemically stable.

[0080] Acid dyes are compounds having an acidic substituent such as a sulfo group or a carboxy group in the dye molecule, or anionic water-soluble dyes that are salts thereof. Acid dyes include those having an acidic substituent such as a sulfo group or a carboxy group and classified as direct dyes. Among these, acid dyes preferably contain a xanthene acid dye, since this can reduce the amount of residue at the opening. Xanthene acid dyes more preferably contain rhodamine acid dyes such as C.I. Acid Red 50, 52, and 289, since this can further reduce the amount of residue at the opening. Furthermore, rhodamine acid dyes more preferably contain C.I. Acid Red 52, since this can increase the blackness of the cured film.

[0081] The basic dye is a compound having a basic group such as an amino group or an imino group in the molecule, or a salt thereof, and is a dye that becomes a cation in an aqueous solution. Among them, the basic dye preferably contains a triarylmethane-based basic dye, since it can increase the blackness of the cured film. The triarylmethane-based basic dye more preferably contains C.I. Basic Blue 7 and / or C.I. Basic Blue 26, since it can further increase the blackness of the cured film.

[0082] The salt-forming compound of an acid dye and a basic dye can be synthesized by a known method. For example, an aqueous solution of an acid dye and an aqueous solution of a basic dye are prepared, and the two are slowly mixed with stirring to produce a salt-forming compound of the acid dye and the basic dye as a precipitate. The salt-forming compound can be obtained by recovering the precipitate by filtration. The obtained salt-forming compound is preferably dried at about 60 to 70°C.

[0083] Furthermore, by adjusting the content of the salt-forming compound in the photosensitive resin composition to 10 parts by weight or more relative to 100 parts by weight of the alkali-soluble resin (A), blackening can be achieved, and by adjusting the content to 75 parts by weight or less, residues in openings can be reduced. By incorporating the salt-forming compound in this range, the alkali solubility of the exposed area, unexposed area, and halftone exposed area, which will be described later, can be favorably adjusted.

[0084] Furthermore, when it is desired to increase the blackness of the cured film, it is preferable to contain a nonionic dye (D3-2) as the coloring material (D).

[0085] (D3-2) Nonionic dyes are dyes other than acid dyes and basic dyes, and do not have an ionic structure.

[0086] Examples of nonionic dyes include azo-based nonionic dyes such as C.I. Disperse Orange 5, C.I. Disperse Red 58, C.I. Disperse Blue 165, and C.I. Solvent Red 18; C.I. Vat Blue 4, C.I. Disperse Red 22, 60, C.I. Disperse Violet 26, 28, and 31; C.I. Disperse Blue 14, 56, and 60; C.I. Solvent Violet 13, 31, and 36; and anthraquinone-based nonionic dyes such as C.I. Solvent Blue 35, 36, 45, 63, 78, 87, 97, 104, and 122.

[0087] Among these, the nonionic dye is preferably an anthraquinone-based nonionic dye, since it can increase the blackness of the cured film.

[0088] <(D1) Organic Pigments> Examples of the (D1) organic pigments used as the (D) coloring material include phthalocyanine pigments, anthraquinone pigments, quinacridone pigments, pyranthrone pigments, dioxazine pigments, thioindigo pigments, diketopyrrolopyrrole pigments, quinophthalone pigments, threne pigments, indoline pigments, isoindoline pigments, isoindolinone pigments, benzofuranone pigments, perylene pigments, aniline pigments, azo pigments, azomethine pigments, condensed azo pigments, carbon black, metal complex pigments, lake pigments, toner pigments, and fluorescent pigments. From the viewpoint of heat resistance, anthraquinone pigments, quinacridone pigments, pyranthrone pigments, diketopyrrolopyrrole pigments, benzofuranone pigments, perylene pigments, condensed azo pigments, and carbon black are preferred.

[0089] In the present invention, the photosensitive resin composition used to form the pixel division layer preferably contains an organic pigment because it provides the pixel division layer with light-blocking properties. By including an organic pigment in the photosensitive resin composition, the pixel division layer contains the organic pigment, which is preferable because it provides the effects described below. In this case, it is preferable that the photosensitive resin composition further contains an organic black pigment and / or a mixed-color organic black pigment (hereinafter, sometimes referred to as component (b)) as the organic pigment (D1).

[0090] Examples of organic black pigments include benzodifuranone-based black pigments, perylene-based black pigments, and azomethine-based black pigments.

[0091] Examples of benzodifuranone-based black pigments include those disclosed in International Publication No. 2009 / 010521. Commercially available benzodifuranone-based black pigments made of a compound represented by formula (5) described below include Irgaphor Black (registered trademark) S0100CF and Experimental Black 582 (both manufactured by BASF).

[0092] Examples of perylene-based black pigments include C.I. Pigment Black 31, C.I. Pigment Black 32, perylenetetracarboxylic acid benzimidazole or its derivatives, and the pigments disclosed in International Publication No. 2005 / 078023. Commercially available products include Spectrasense (registered trademark) Black S0084, L0086, K0087, and K0088 (all manufactured by BASF).

[0093] Examples of azomethine black pigments include the pigments disclosed in U.S. Patent Application Publication No. 2002-121228. A commercially available product that can be used is Chromofine Black A1103 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.).

[0094] The mixed color organic black pigment refers to a pigment mixture containing (b-1) an organic pigment of at least one color selected from an organic yellow pigment, an organic red pigment, and an organic orange pigment (hereinafter, sometimes referred to as component (b-1)), and (b-2) an organic pigment of at least one color selected from an organic blue pigment and an organic purple pigment (hereinafter, sometimes referred to as component (b-2)), in which the content of component (b-2) is 20% by weight or more relative to the total amount of component (b-1) and component (b-2).

[0095] Examples of organic yellow pigments include C.I. Pigment Yellow 24, 120, 138, 139, 151, 175, 180, 185, 181, 192, 193, and 194. Examples of organic orange pigments include C.I. Pigment Orange 13, 36, 43, 60, 61, 62, 64, 71, and 72. Examples of organic red pigments include C.I. Pigment Red 122, 123, 149, 178, 177, 179, 180, 189, 190, 202, 209, 254, 255, and 264. Examples of organic blue pigments include C.I. Examples of organic purple pigments include C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:6, 16, 25, 56, 57, 60, 61, 64, 65, 66, 75, 79, and 80. Examples of organic purple pigments include C.I. Pigment Violet 19, 23, 29, 32, and 37.

[0096] Of the components corresponding to the component (b) above, in order to reduce unevenness in brightness, the component (b) contained in the pixel dividing layer of the organic EL display device of the present invention preferably contains an organic black pigment, and the organic black pigment contains a compound represented by formula (5) or formula (6) and / or an isomer thereof. It is more preferable that the component (b) contained in the pixel dividing layer contains a compound represented by formula (7) or an isomer thereof. The compounds represented by formulas (5) to (7) can be synthesized by reacting 2,5-dihydroxy-1,4-benzenediacetic acid with isatin or a derivative thereof in the presence of an acid catalyst, and then converted into a pigment.

[0097]

[0098]

[0099] In formula (5) and formula (6), R ２２ １ ~R ３１ １０ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.

[0100]

[0101] In order to further suppress unevenness in brightness, the component corresponding to component (b) may be subjected to a micronization treatment by a known method such as a solvent salt milling method or an acid paste method. When micronizing a benzodifuranone black pigment, the coexistence of the compound represented by formula (8) or a salt thereof and adsorption onto the pigment surface may facilitate the suppression of unevenness in brightness.

[0102]

[0103] In formula (8), n and m represent integers, each independently being an integer of 0 to 2, provided that n+m≧1 is satisfied.

[0104] Furthermore, when component (b) contains a benzodifuranone-based black pigment, it is preferable that the pigment surface has a coating layer containing silica in order to improve developability and suppress development residues in the openings. The silica contained in the coating layer here is not the aforementioned component (a), but is considered to be a part of component (b).

[0105] The content of component (b) in the pixel dividing layer is preferably 1% by weight or more, more preferably 10% by weight or more, in order to achieve high light-blocking properties, and is preferably 50% by weight or less, more preferably 30% by weight or less, in order to reduce unevenness in brightness.

[0106] In addition to the component (b), when the component (a) is further contained, the content of the component (a) relative to 100 parts by weight of the component (b) is such that the content of SiO ２ In other words, in the organic EL display device of the present invention, the content of the component (a) relative to the component (b) in the pixel dividing layer is preferably 20 to 70 parts by weight, more preferably 30 to 50 parts by weight, calculated as SiO ２ The amount is preferably 20 to 70 parts by weight in terms of conversion.

[0107] <(E) Liquid-Repellent Material> When the organic EL layer is formed by an inkjet method, the photosensitive resin composition used in the present invention preferably contains a liquid-repellent material. Known materials such as fluorine-based polymers and fluorine-containing compounds having a silane compound can be used, but a liquid-repellent material having at least an amide group or a urethane group is preferred. The presence of an amide group or a urethane group improves compatibility with the alkali-soluble resin (A) described above, reduces defects such as repelling, and improves the film thickness uniformity of the cured film, thereby reducing display defects in display devices.

[0108] Examples of liquid-repellent materials include 2-(perfluorobutyl)ethyl (meth)acrylate and 2-(perfluorohexyl)ethyl (meth)acrylate, which are (meth)acrylate monomers having a perfluoroalkyl group, and commercially available products such as "Megafac (registered trademark)" RS-72-K, RS-72-A, RS-75, RS-76-E, RS-76-NS, RS-78, and RS-90 (manufactured by DIC Corporation).

[0109] Preferable examples of the epoxy group-containing (meth)acrylate monomer include glycidyl acrylate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether (4-HBAGE), 4-hydroxybutyl methacrylate glycidyl ether, acrylates having an alicyclic epoxy group, and methacrylates having an alicyclic epoxy group.

[0110] The liquid-repellent material (E) having an amide group or a urethane group may also be a copolymer obtained by copolymerizing different functional group-substituted (meth)acrylic monomers. Copolymerizing different functional group-substituted (meth)acrylic monomers can more easily balance liquid repellency and solubility. Examples of such materials include hydroxyl group-containing (meth)acrylates, hydroxyl group-containing (meth)acrylamides, alkoxy group-containing (meth)acrylates, blocked isocyanate group-containing (meth)acrylates, phenoxy group-containing (meth)acrylates, alkyl (meth)acrylates, and vinyl group-containing compounds. Examples of hydroxyl group-containing (meth)acrylates include 2-hydroxyethyl (meth)acrylate. Examples of hydroxyl group-containing (meth)acrylamides include N-hydroxymethyl acrylamide. Examples of alkoxy group-containing (meth)acrylates include 3-methacryloxypropylmethyldimethoxysilane. Examples of blocked isocyanate group-containing (meth)acrylates include 2-(0-[1'-methylpropylideneamino]carboxyamino)ethyl methacrylate (Karenz MOI-BM: registered trademark, manufactured by Showa Denko K.K.). Examples of phenoxy group-containing (meth)acrylates include 2-phenoxybenzyl acrylate and 3-phenoxybenzyl acrylate. Examples of alkyl (meth)acrylates include diluent monomers such as alkyl acrylates, which are unsubstituted or substituted alkyl (meth)acrylates having a linear, branched, and / or cyclic alkyl group having 1 to 12 carbon atoms, which are unsubstituted or substituted with at least one of an amino group, a monoalkylamino group, a dialkylamino group, a hydrocarbon aromatic ring, and a heterocycle, or which may undergo cleavage addition of an acid anhydride to the hydroxy group. Examples of vinyl group-containing compounds include n-butyl vinyl ether.

[0111] The compound contained in the liquid-repellent material (E) having an amide group or a urethane group is typically a (co)polymer. The (co)polymer as the compound contained in the liquid-repellent material (E) can be obtained by a known polymerization method. The (co)polymer may be obtained, for example, by ionic polymerization such as radical polymerization or anionic polymerization. The (co)polymer may also be a random copolymer, a block copolymer, a graft (co)polymer, or an alternating copolymer. Here, a radical (co)polymerization method is used as an example. For example, the liquid-repellent material (E) can be obtained by random copolymerization of a predetermined amount of dimethyl(meth)acrylamide, a predetermined amount of a fluorine-containing (meth)acrylate monomer, and, if necessary, predetermined amounts of epoxy group-containing (meth)acrylates, hydroxyl group-containing (meth)acrylates, hydroxyl group-containing (meth)acrylamides, alkoxy group-containing (meth)acrylates, blocked isocyanate group-containing (meth)acrylates, phenoxy group-containing (meth)acrylates, alkyl (meth)acrylates, or vinyl group-containing compounds in an appropriate solvent with a radical polymerization initiator. During random copolymerization, a chain transfer agent may be added as needed. As the radical polymerization initiator, for example, tert-butylperoxy-2-ethylhexanoate can be used. As the chain transfer agent, for example, dodecyl mercaptan can be used. Furthermore, as the solvent, for example, an inert solvent such as cyclohexanone can be used.

[0112] The weight-average molecular weight of the liquid-repellent material (E) having an amide group or a urethane group is preferably in the range of 1,500 to 50,000. A molecular weight within this range allows for easier dissolution in the solvent used in the photosensitive resin composition. Furthermore, a molecular weight within this range is preferable because it enhances the defoaming properties of the photosensitive resin composition solution. The amount of the liquid-repellent material (E) having an amide group or a urethane group per 100 parts by weight of the alkali-soluble resin (A) is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, from the viewpoint of making it difficult for liquid repellency to develop within pixels and making it easier to obtain high durability. Furthermore, the amount is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, from the viewpoint of making it difficult for liquid repellency to develop within pixels and making it easier to obtain high durability.

[0113] <Spacers> In the organic EL display device of the present invention, spacers 4 are provided on the pixel division layer. The first objective of providing spacers is to reduce the contact area between the substrate and the deposition mask during the formation of the organic EL layer, thereby suppressing particle generation during the process. This, in turn, reduces panel yield and light-emitting element degradation. As a second objective, as mentioned above, spacers must be formed on the pixel division layer to support the structure covering the second electrode in subsequent processes and ensure the strength of the display device. Like the pixel division layer, spacers require patterning, and residues from removed areas can directly lead to defects such as short circuits and black spots. Furthermore, because the shape of the spacer's edges can cause disconnection of the second electrode, a gentle forward tapered shape is also required for ease of processing.

[0114] The spacer can be any material having the necessary mechanical and electrical properties, and is therefore not limited to either a known organic or inorganic material, but is preferably a cured film of a photosensitive resin composition from the viewpoint of processability. Furthermore, by forming the spacer using the same material as the pixel dividing layer in a single process, it is possible to shorten the process time, thereby improving the panel yield and reducing costs.

[0115] As described above, the problem of peeling between the pixel division layer and the organic EL layer also occurs at the interface where the spacer and the organic EL layer contact each other. Therefore, in the present invention, when the maximum value of the surface roughness (Ra1) of the pixel division layer and the surface roughness (Ra2) of the spacer is defined as Ramax, Ramax is 1.0 nm or more and 50 nm or less. Furthermore, it is more preferable that the surface roughness (Ra2) of the spacer is Ramax. Furthermore, both the surface roughness (Ra1) of the pixel division layer and the surface roughness (Ra2) of the spacer may be Ramax. Note that the surface roughness of the spacer can also be measured with an atomic force microscope (AFM), just like the pixel division layer.

[0116] Furthermore, since the spacer is formed on the outermost surface of the substrate, the surface of the spacer forms the interface with the organic EL layer. Conventionally, poor adhesion between the spacer and the organic EL layer has led to peeling, which has been a major issue, particularly in flexible products. In the present invention, an anchoring effect can be achieved by setting the surface roughness (Ra2) of the spacer to 1.0 nm or more, preferably 5.0 nm or more, and more preferably 20 nm or more, to improve adhesion with the organic EL layer. While a surface roughness (Ra2) of 1.0 nm or more can achieve the anchoring effect, it is preferable to set the surface roughness (Ra2) to 50 nm or less in order to suppress pinholes in the second electrode and defects in the sealing process described below. Furthermore, when increasing Ra2 to improve adhesion, it is effective to ensure that the interface where the spacer and the organic EL layer contact is as large as possible. When Ra2 is larger than the surface roughness Ra1 of the pixel division layer, i.e., when Ra2 is equal to Ramax, it is preferable that the area of ​​the interface where the spacer and the organic EL layer contact is 50% or more of the area of ​​the interface where the substrate and the organic EL layer contact. This means that the spacers cover 50% or more of the surface area of ​​the substrate.

[0117] When Ra1 and Ra2 are large, such as 1.0 nm or more, in addition to the effect of improving adhesion, the substrate can also increase the diffuse reflection of the substrate, thereby suppressing the reflection of external light in the display device. Generally, when external light is incident on a substrate, two types of reflected light are generated on the substrate surface: specular reflection and diffuse reflection, and the sum of these reflects the amount of reflected light. However, specular reflection has a large influence on what humans perceive as glare or reflection. In other words, in order to maintain the display quality of the display device, it is effective to increase the diffuse reflection of the substrate and reduce the specular reflection. That is, by increasing Ra1 and Ra2, which are the surface roughnesses of the pixel division layer and spacer included on the surface of the substrate, to 1.0 nm or more, the diffuse reflection on the substrate surface increases, which ultimately leads to ensuring the display quality of the display device.

[0118] Furthermore, if the absolute value of the difference between Ra1 and Ra2 is 1.0 nm or more, two types of anchoring effects are obtained, which is more preferable in terms of improving adhesion.

[0119] In addition, since the shape of the edge of the spacer may cause disconnection of the second electrode, a gentle forward tapered shape is preferable. Here, the forward tapered shape refers to a state in which the angle formed by the tangent line at the interface between the pixel dividing layer and the spacer and the tangent line at a position on the surface of the tapered portion of the spacer at a film thickness that is 50% of the maximum thickness of the spacer is less than 90 degrees.

[0120] The thickness of the spacer is usually 0.3 μm to 10 μm, but is not particularly limited as long as it is sufficient for contact with the deposition mask and for supporting the structure covering the second electrode.

[0121] <Organic EL Layer> In the organic EL display device of the present invention, the configuration of the organic EL layer 5 is not particularly limited and may be, for example, any of (1) hole transport layer / light-emitting layer, (2) hole transport layer / light-emitting layer / electron transport layer, or (3) light-emitting layer / electron transport layer. Furthermore, a tandem type in which a plurality of the above configurations are stacked with a charge generation layer interposed therebetween may be used. The charge generation layer is generally also called an electron extraction layer, connection layer, intermediate layer, intermediate electrode, intermediate conductive layer, or intermediate insulating layer, and may be made of known materials. A tandem type configuration is preferred because it is expected to improve luminance and emission life. Specific examples of the tandem type include stacked structures including a charge generation layer between an anode and a cathode, such as (4) hole transport layer / light-emitting layer / electron transport layer / charge generation layer / hole transport layer / light-emitting layer / electron transport layer, (5) hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer / charge generation layer / hole injection layer / hole transport layer / light-emitting layer / electron transport layer / electron injection layer, and (6) hole transport layer / light-emitting layer / electron transport layer / charge generation layer / hole transport layer / light-emitting layer / electron transport layer / charge generation layer / hole transport layer / light-emitting layer / electron transport layer.

[0122] Each of the above layers may be a single layer or multiple layers, and may be doped. In particular, the electron transport layer and charge generation layer are preferably metal-doped layers doped with a metal, which can improve the electron transport ability and the electron injection ability into adjacent layers. In addition to the above layers, a protective layer (cap layer) may be further provided, which can further improve the luminous efficiency by optical interference. The thickness of each layer is generally selected from the range of 1 to 200 nm, taking into account the resistance value of each layer material and its influence on the extraction efficiency of EL light.

[0123] <Hole Transport Layer> The hole transport layer is formed, for example, by laminating or mixing one or more hole transport materials, or by using a mixture of a hole transport material and a polymer binder. Alternatively, the hole transport layer may be formed by adding an inorganic salt such as iron (III) chloride to the hole transport material. The hole transport material is not particularly limited as long as it is a compound that can form a thin film necessary for fabricating a light-emitting device, can inject holes from the anode electrode, and can transport holes. The hole transport layer may be a single layer or may be formed by laminating multiple layers.

[0124] Suitable examples of the hole transport material include triphenylamine derivatives such as 4,4'-bis(N-(3-methylphenyl)-N-phenylamino)biphenyl, 4,4'-bis(N-(1-naphthyl)-N-phenylamino)biphenyl, and 4,4',4"-tris(3-methylphenyl(phenyl)amino)triphenylamine; biscarbazole derivatives such as bis(N-allylcarbazole) and bis(N-alkylcarbazole); heterocyclic compounds such as pyrazoline derivatives, stilbene compounds, hydrazone compounds, benzofuran derivatives, thiophene derivatives, oxadiazole derivatives, phthalocyanine derivatives, and porphyrin derivatives; and polymers such as polycarbonates and styrene derivatives having the above-mentioned monomers in their side chains, polythiophenes, polyanilines, polyfluorenes, polyvinylcarbazoles, and polysilanes.

[0125] <Light-emitting layer> In the light-emitting layer, the injected electrons and holes recombine to emit light. A major feature of organic EL display devices is that they can emit a variety of colors by selecting the materials that make up this light-emitting layer.

[0126] The light-emitting layer is a layer in which a light-emitting material is excited by recombination energy due to collisions of holes and electrons, thereby emitting light. The light-emitting layer may be a single layer or may be composed of multiple layers stacked together, each of which is formed from a light-emitting material (host material and / or dopant material). Each light-emitting layer may be composed of only one of a host material or a dopant material, or may be composed of a combination of one or more host materials and one or more dopant materials. That is, in each light-emitting layer, only the host material or the dopant material may emit light, or both the host material and the dopant material may emit light. From the viewpoint of efficiently utilizing electrical energy and obtaining light emission with high color purity, it is preferable that the light-emitting layer be composed of a combination of a host material and a dopant material. The dopant material may be contained entirely or partially in the host material.

[0127] The content of the dopant material in the light-emitting layer is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, based on 100 parts by weight of the host material, from the viewpoint of suppressing concentration quenching.

[0128] The light-emitting layer can be formed by a method of co-evaporating a host material and a dopant material, or a method of mixing a host material and a dopant material in advance and then evaporating the mixture.

[0129] Examples of host materials constituting the light-emitting material include compounds having a fused aryl ring, such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthacene, triphenylene, perylene, fluoranthene, fluorene, and indene. Two or more of these may be used. Suitable hosts used when the light-emitting layer exhibits triplet emission (phosphorescence) include metal-chelated oxinoid compounds, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, indolocarbazole derivatives, triazine derivatives, and triphenylene derivatives. Among these, compounds having an anthracene skeleton or a pyrene skeleton are more preferred because they are more likely to provide highly efficient light emission.

[0130] Examples of dopant materials constituting the light-emitting material include fused ring derivatives such as anthracene and pyrene, metal complex compounds such as tris(8-quinolinolato)aluminum, bisstyryl derivatives such as bisstyryl anthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, dibenzofuran derivatives, carbazole derivatives, indolocarbazole derivatives, and polyphenylenevinylene derivatives. Dopant materials used when the light-emitting layer exhibits triplet emission (phosphorescence) are preferably metal complex compounds containing at least one metal selected from the group consisting of iridium (Ir), ruthenium (Ru), palladium (Pd), platinum (Pt), osmium (Os), and rhenium (Re). The ligands constituting the metal complex compounds can be appropriately selected based on the required emission color, organic EL display device performance, and relationship with the host compound, and preferably have a nitrogen-containing aromatic heterocycle such as a phenylpyridine skeleton, a phenylquinoline skeleton, or a carbene skeleton. Specific examples include tris(2-phenylpyridyl)iridium complex, bis(2-phenylpyridyl)(acetylacetonate)iridium complex, tetraethylporphyrin platinum complex, etc. Two or more of these may be used.

[0131] <Electron Transport Layer> The electron transport layer transports electrons injected from the cathode to the light-emitting layer. To achieve a low driving voltage, the organic EL layer of the present invention preferably includes an electron transport layer. It is desirable for the electron transport layer to have high electron injection efficiency and efficiently transport injected electrons. Therefore, the electron transport layer is preferably made of a material that has high electron affinity and electron mobility, excellent stability, and is unlikely to generate impurities that trap electrons during production or use. In particular, when the film thickness is large, low-molecular-weight compounds are prone to deterioration of film quality due to crystallization, so compounds with a molecular weight of 400 or more are preferred. Considering the balance between hole and electron transport, it is also preferable for the electron transport layer to efficiently block the flow of non-recombined holes from the anode to the cathode. The electron transport layer in the present invention also includes a hole-blocking layer that can efficiently block hole migration. The electron transport layer may be a single layer or a laminate of multiple layers.

[0132] Examples of electron transport materials constituting the electron transport layer include condensed polycyclic aromatic derivatives such as naphthalene and anthracene. Two or more of these may be used. Among these, compounds having a heteroaryl ring structure containing electron-accepting nitrogen are preferred because they can further reduce the driving voltage and achieve highly efficient light emission.

[0133] The electron-accepting nitrogen referred to here refers to a nitrogen atom that forms a multiple bond with an adjacent atom. Because the nitrogen atom has high electronegativity, such multiple bonds have electron-accepting properties. Therefore, aromatic heterocycles containing electron-accepting nitrogen have high electron affinity. Electron-transporting materials containing electron-accepting nitrogen can easily accept electrons from a cathode with high electron affinity, thereby further reducing the driving voltage. Furthermore, the supply of electrons to the light-emitting layer increases, increasing the recombination probability and improving the luminous efficiency.

[0134] Examples of heteroaryl rings containing electron-accepting nitrogen include triazine rings and pyridine rings. As compounds having these heteroaryl ring structures, triazole derivatives such as N-naphthyl-2,5-diphenyl-1,3,4-triazole, bipyridine derivatives such as 2,5-bis(6'-(2',2"-bipyridyl))-1,1-dimethyl-3,4-diphenylsilole, and terpyridine derivatives such as 1,3-bis(4'-(2,2':6'2"-terpyridinyl))benzene are preferably used from the viewpoint of electron transport ability. Two or more of these may be used.

[0135] Furthermore, compounds having a phenanthroline skeleton can be cited as substances that satisfy the conditions required for the electron transport layer. To obtain stable light emission over a long period of time, a material with excellent thermal stability and thin film formability is desired. Among compounds having a phenanthroline skeleton, those in which the substituent itself has a three-dimensional structure, those in which the three-dimensional structure is formed due to steric repulsion with the phenanthroline skeleton or with an adjacent substituent, or those in which multiple phenanthroline skeletons are linked are preferred. Furthermore, when multiple phenanthroline skeletons are linked, compounds containing a conjugated bond, a substituted or unsubstituted aromatic hydrocarbon, or a substituted or unsubstituted aromatic heterocycle in the linking unit are more preferred.

[0136] The electron transport material does not need to be limited to a single compound having a phenanthroline skeleton; a mixture of multiple such compounds may be used, or one or more known electron transport materials may be mixed with the compound. Known electron transport materials include, but are not limited to, quinolinol derivative metal complexes, such as 8-hydroxyquinoline aluminum, benzoquinoline metal complexes, tropolone metal complexes, flavonol metal complexes, perylene derivatives, perinone derivatives, naphthalene, coumarin derivatives, oxadiazole derivatives, aldazine derivatives, bisstyryl derivatives, pyrazine derivatives, phenanthroline derivatives, quinoline derivatives, benzimidazole derivatives, triazole derivatives, quinoxaline derivatives, and benzoquinoline derivatives. These electron transport materials may be used alone or may be layered or mixed with different electron transport materials. Compounds having a nitrogen-containing aromatic heterocycle, such as phenanthroline derivatives and oligopyridine derivatives, may also be used. In particular, compounds having a phenanthroline skeleton, as described below, are preferred because they exhibit excellent electron transport properties.

[0137] The above electron transport material may be used alone, or two or more of the above electron transport materials may be mixed together, or one or more other electron transport materials may be mixed with the above electron transport material. Furthermore, the electron transport layer of the present invention preferably contains a donor dopant material. Here, the donor dopant material is a compound that improves the electron injection barrier, thereby facilitating electron injection from the cathode or electron injection layer into the electron transport layer and further improving the electrical conductivity of the electron transport layer. In the present invention, the donor dopant material preferably contains one or more materials selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, inorganic salts of these metals, and complexes of these metals with organic substances. As donor dopant materials, inorganic salts or complexes of organic substances are preferred over simple metals because they are easily vapor-deposited in a vacuum and easy to handle. Complexes of organic substances are more preferred because they are easy to handle in air and the addition concentration can be easily adjusted.

[0138] <Charge Generation Layer> The charge generation layer generally consists of a double layer. Specifically, a pn junction charge generation layer consisting of an n-type charge generation layer and a p-type charge generation layer can be used. When a voltage is applied to the organic EL layer, the pn junction charge generation layer generates charges or separates the charges into holes and electrons, and injects these holes and electrons into the light-emitting layer via the hole transport layer and electron transport layer. Specifically, it functions as an intermediate charge generation layer for the multiple light-emitting layers contained in the organic EL layer. The n-type charge generation layer supplies electrons to the light-emitting layer located on the anode side, and the p-type charge generation layer supplies holes to the light-emitting layer located on the cathode side. This further improves the luminance and luminous efficiency of the organic EL layer containing multiple light-emitting layers, reduces the driving voltage, and improves the light-emitting life of the organic EL layer. For these reasons, it is preferable that the organic EL layer in the present invention includes a charge generation layer. Furthermore, as will be described later, in the present invention, it is preferable that the charge generating layer contains a donor dopant material, and it is preferable that the donor dopant material contains one or more materials selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, inorganic salts of these metals, and complexes of these metals with organic substances.

[0139] The n-type charge generating layer preferably comprises an n-type dopant material and a host material, and known materials can be used for these. For example, an alkali metal, an alkaline earth metal, or a rare earth metal can be used as the n-type dopant material. Furthermore, a compound having a phenanthroline skeleton and a compound having a nitrogen-containing aromatic heterocycle, such as an oligopyridine derivative, can be used as the host material. In particular, a compound having a phenanthroline skeleton, which will be described later, is preferred because it exhibits excellent properties as a host material for the n-type charge generating layer, and these may be used in combination.

[0140] The p-type charge generating layer preferably comprises a p-type dopant material and a host material, and known materials can be used for these. For example, p-type dopant materials include tetrafluorene-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), tetracyanoquinodimethane derivatives, radialene derivatives, iodine, and FeCl.３ , FeF ３ , SbCl ５ The p-type dopant material is preferably a radialene derivative, and the host material is preferably an arylamine derivative.

[0141] <Compound Having a Phenanthroline Skeleton> In the present invention, the electron transport layer and / or the charge generation layer preferably contains a compound having a phenanthroline skeleton represented by the following general formula (1).

[0142]

[0143] Here, R １ ~R ８ may be the same or different and are selected from a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, a heteroaryl group, and a heterocyclic group. １ , R ３ , R ６ , R ８ At least one of these is selected from the group consisting of an adamantyl group, a norbornyl group, a phenylvinyl group, a β-naphthyl group, a phenanthrene group, and a pyrenyl group.

[0144] Furthermore, in the present invention, the electron transport layer and / or the charge generation layer more preferably contains a compound having a phenanthroline skeleton represented by the following general formula (2).

[0145]

[0146] Here, R ９ ~R １６ may be the same or different and are selected from a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, a heteroaryl group, a heterocyclic group, and X1. ９ ~R １６At least one of the above is X1, and n represents a natural number of 2 to 6. X1 is a single bond or an n-valent linking unit derived from benzene, anthracene, pyridine, ethylene, thiophene, furan, methylene, carbazole, cyclohexane, spirobifluorene, triphenylamine, triptycene, or a structure formed by combining these, which links multiple phenanthroline skeletons.

[0147] Among these substituents, the alkyl group refers to a saturated aliphatic hydrocarbon group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, or a tert-butyl group, which may or may not have a substituent. When substituted, the additional substituent is not particularly limited, and examples thereof include an alkyl group, a halogen atom, an aryl group, and a heteroaryl group, and this point is also applicable to the following description. The number of carbon atoms in the alkyl group is not particularly limited, but in terms of availability and cost, it is preferably 1 to 20, more preferably 1 to 8. The cycloalkyl group refers to a saturated alicyclic hydrocarbon group such as a cyclopropyl group, a cyclohexyl group, a norbornyl group, or an adamantyl group, which may or may not have a substituent. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 3 to 20. The aralkyl group refers to an aromatic hydrocarbon group connected via an aliphatic hydrocarbon, such as a benzyl group or a phenylethyl group, and both the aliphatic hydrocarbon and the aromatic hydrocarbon may be unsubstituted or substituted. Furthermore, the term "alkenyl group" refers to an unsaturated aliphatic hydrocarbon group containing a double bond, such as a vinyl group, an allyl group, or a butadienyl group, which may be unsubstituted or substituted. The term "cycloalkenyl group" refers to an unsaturated alicyclic hydrocarbon group containing a double bond, such as a cyclopentenyl group, a cyclopentadienyl group, or a cyclohexene group, which may be unsubstituted or substituted. The term "alkynyl group" refers to an unsaturated aliphatic hydrocarbon group containing a triple bond, such as an acetylenyl group, which may be unsubstituted or substituted. The term "alkoxy group" refers to an aliphatic hydrocarbon group connected via an ether bond, such as a methoxy group, which may be unsubstituted or substituted. The term "alkylthio group" refers to an alkoxy group in which the oxygen atom of the ether bond is substituted with a sulfur atom. The term "aryl ether group" refers to an aromatic hydrocarbon group connected via an ether bond, such as a phenoxy group, which may be unsubstituted or substituted. The term "arylthioether group" refers to an aryl ether group in which the oxygen atom of the ether bond is substituted with a sulfur atom.Furthermore, the term "aryl group" refers to an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, a biphenyl group, a phenanthryl group, a terphenyl group, or a pyrenyl group, which may be unsubstituted or substituted. The term "heterocyclic group" refers to an aliphatic ring having atoms other than carbon within the ring, such as a pyran ring, a piperidine ring, or a cyclic amide, which may or may not have a substituent. The number of carbon atoms in the heterocyclic group is not particularly limited, but is preferably in the range of 2 to 20. The term "halogen" refers to fluorine, chlorine, bromine, or iodine. The term "haloalkane," "haloalkene," or "haloalkyne" refers to a group in which part or all of the aforementioned alkyl group, alkenyl group, or alkynyl group, such as a trifluoromethyl group, is substituted with the aforementioned halogen, and the remaining portion may be substituted or unsubstituted. The aldehyde group, carbonyl group, ester group, carbamoyl group, and amino group include those substituted with aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, heterocycles, etc., and the aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and heterocycles may be unsubstituted or substituted. The silyl group refers to a silicon compound group such as a trimethylsilyl group, which may be unsubstituted or substituted. The siloxanyl group refers to a silicon compound group connected via an ether bond, such as a trimethylsiloxanyl group, which may be unsubstituted or substituted. Furthermore, a ring structure may be formed between adjacent substituents. The formed ring structure may be unsubstituted or substituted.

[0148] Furthermore, when a substituent itself has a three-dimensional structure, or when a three-dimensional structure is imparted by steric repulsion with the phenanthroline skeleton or adjacent substituents, compounds containing the phenanthroline skeleton have low planarity and are less likely to crystallize, allowing them to maintain a good amorphous thin film state. Substituents that themselves have a three-dimensional structure refer to bulky structures that are not two-dimensionally planar, such as t-butyl groups, adamantyl groups, and norbornyl groups, and may be unsubstituted or substituted. Substituents that impart a three-dimensional structure due to steric repulsion with the phenanthroline skeleton or adjacent substituents refer to groups such as α-naphthyl groups, phenanthrene groups, and mesityl groups, which, even if the substituent itself has a planar structure, have a plane that is different from the plane of the phenanthroline skeleton due to steric repulsion between the substituent and the phenanthroline skeleton or between the substituent and adjacent substituents. These can be examined using molecular models, computational chemistry, and the like.

[0149] Furthermore, by linking multiple phenanthroline skeletons, the compound containing the phenanthroline skeleton has a high molecular weight and a higher glass transition temperature, which also makes it less likely to crystallize and allows the compound to maintain a good amorphous thin film state.

[0150] In the compounds having the phenanthroline skeleton of general formula (1) of the present invention, it is more preferable to introduce substituents into the 2-, 4-, 7-, and 9-positions of the phenanthroline skeleton. These substituents are the same as those described above. Specific examples of the compounds having the phenanthroline skeleton include, but are not limited to, the structures shown below.

[0151]

[0152]

[0153]

[0154]

[0155] The host material of the electron transport layer and / or the charge generation layer does not need to be limited to only one compound having a phenanthroline skeleton, and a mixture of two or more compounds having a phenanthroline skeleton may be used, or one or more known host materials may be mixed with a compound having a phenanthroline skeleton. The known host material is not particularly limited, and examples thereof include previously known fused ring derivatives such as anthracene, phenanthrene, pyrene, perylene, and chrysene; metal complexes of quinolinol derivatives such as tris(8-quinolinolato)aluminum; benzoxazole derivatives, stilbene derivatives, benzthiazole derivatives, thiadiazole derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, oxadiazole derivatives, bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives; metal complexes of quinolinol derivatives combined with different ligands; oxadiazole derivative metal complexes; benzazole derivative metal complexes; coumarin derivatives; pyrrolopyridine derivatives; perinone derivatives; thiadiazolopyridine derivatives; and, in the case of polymers, polyphenylenevinylene derivatives, polyparaphenylene derivatives, and polythiophene derivatives.

[0156] Furthermore, a compound having a phenanthroline skeleton may be used as a dopant material, but is preferably used as a host material because of its excellent electron transporting ability.

[0157] <Second Electrode> In the present invention, the second electrode 6 must be a light-reflective electrode in the case of a bottom emission type, and a light-transmitting electrode in the case of a top emission type.

[0158] For bottom-emission devices, materials that exhibit high visible light reflectance and low electrical resistance above a certain film thickness are preferred, and Ag or Ag alloy films containing Ag as the main component are useful because of their high reflectance. As the Ag alloy film, an MgAg alloy containing Ag as the main component can be used. Furthermore, Al or Al alloy films containing Al as the main component are also suitable as second electrodes for bottom emission. An AlCr alloy film containing Cr and an AlNi alloy film containing Ni are preferred because they have high reflectance comparable to that of pure Al and can achieve low electrical resistance.

[0159] For top-emission devices, conductive metal oxides such as transparent tin oxide, indium oxide, and indium tin oxide (ITO) can be used, but a thin film of an MgAg alloy that can be produced by vapor deposition is preferred in order to avoid damage to the organic EL layer.

[0160] The resistance of the second electrode, like the first electrode, is not limited as long as it can supply a current sufficient for the light emitting element to emit light, but a low resistance is desirable from the viewpoint of the power consumption of the light emitting element. The thickness of the electrode can be selected arbitrarily according to the characteristics such as transmittance and resistance value, but can be between 100 and 300 nm for a bottom emission type and between 10 and 30 nm for a top emission type.

[0161] <Wiring and TFT> In the present invention, as described above, wiring and driving circuits such as TFTs 7 may be provided as components included in the substrate 1 in some cases.

[0162] When the organic EL display device is of an active drive top emission type, the patterned island-shaped first electrode 2 is often connected to a TFT 7 formed in advance as part of the substrate 1 .

[0163] TFT semiconductor layers include a-Si (amorphous silicon), p-Si (polycrystalline silicon), microcrystalline silicon, oxides such as In-Ga-Zn-O, and LTPO (Low Temperature Polycrystalline Oxide), which combines p-Si and oxides. Two types are commonly used: a-Si TFTs and p-Si TFTs. While a-Si TFTs have low mobility, an index of electron mobility, they can be manufactured using a relatively short manufacturing process and can be fabricated on large substrates, allowing them to be used in a wide range of displays, from small to large. On the other hand, p-Si TFTs have high mobility and allow driver circuits and other components to be formed on the substrate. Because the manufacturing process is longer than a-Si and manufacturing on large substrates is more difficult, they are primarily used in small- to medium-sized displays. In particular, the p-Si in p-Si TFTs can generally be formed by irradiating a-Si as a starting film with laser light, causing instant melting and crystallization. Furthermore, there is a doping process that is not used in the manufacturing process of a-Si TFTs, in which phosphorus or boron is implanted into Si, and the threshold value of the TFT characteristics may be controlled by doping impurities into the Si film.

[0164] TFTs can be broadly classified into bottom-gate and top-gate types based on their structure. A bottom-gate type is preferable for a-Si TFTs, while a top-gate type is preferable for p-Si TFTs. For example, in a top-gate type, drain and source electrodes are connected to the semiconductor layer, and a gate electrode is provided above the semiconductor layer. TFTs are formed on a substrate by repeating the elemental processes of thin-film formation, patterning, etching, and cleaning several times. Known methods can be used to form TFTs. Furthermore, in a bottom-gate type, the gate electrode is located at the bottom, with a semiconductor layer / insulating film above it, and a source electrode and drain electrode formed above that. Connecting the gate electrode, source electrode, and drain electrode with straight lines forms an inverted triangle, which may also be called an "inverted staggered structure."

[0165] <Planarization Layer> In particular, when wiring and TFTs 7 are provided inside the substrate 1, as shown in FIG. 2, as in an active-drive type, it is preferable to use a planarization layer 8. By providing the planarization layer 8, the unevenness of the wiring and TFTs 7 can be covered and planarized. In this case, since the first electrode 2 is provided on the planarization layer, it is preferable that the first electrode 2 and the wiring and TFTs 7 are connected through contact holes formed in the planarization layer 8. The planarization layer 8 is not limited to either a known organic or inorganic material, but preferably includes a cured film of a photosensitive resin composition from the standpoint of processability. The planarization layer 8 can be applied by a wet coating method such as spin coating, slit coating, dip coating, spray coating, or printing, which can form a thin, uniform film on a large-sized substrate.

[0166] The photosensitive resin composition preferably contains (A) an alkali-soluble resin, (B) a photosensitizer, and (C) an organic solvent, and may further contain (D) a coloring material. By incorporating a combination of (A) an alkali-soluble resin and (B) a photosensitizer into the photosensitive resin composition, pattern processing utilizing photosensitivity becomes possible. Furthermore, by incorporating (C) an organic solvent, the composition can be made into a varnish state, which may improve coatability. Furthermore, by incorporating (D) a coloring material into the photosensitive resin composition, the planarizing layer can be blackened. The photosensitive resin composition may further contain other components.

[0167] Examples of the alkali-soluble resin (A) include acrylic resin, epoxy resin, polyamide resin, siloxane resin, and precursors of these resins, and the film thickness is not particularly limited as long as it is sufficient to cover the irregularities. When coloring is required from the viewpoint of light-shielding properties or anti-reflection, it is preferable to contain an appropriate coloring material.

[0168] <Sealing layer> After forming the second electrode, it is preferable to seal it with a sealing layer 9 as shown in Fig. 5, for example. This is because organic EL light-emitting elements are considered to be vulnerable to oxygen and moisture, and in order to obtain a highly reliable display device, it is preferable to perform sealing in an atmosphere with as little oxygen and moisture as possible. It is also preferable to select a material with high gas barrier properties for use in the sealing layer 9, and similarly to the substrate 1, it is appropriately selected from glass, resin film, gas barrier film, etc. For example, an example of a gas barrier film is SiO ２ (silicon oxide), SiN (silicon nitride), SiON (silicon oxynitride), etc. ２ A sealing layer 9 made of a resin material such as an acrylic resin or a silicone resin may be provided on a layer made of a material such as silicon dioxide (SiO2), silicon nitride (SiN), or silicon oxynitride (SiON). In the case of a top-emission display device, it is preferably made of a light-transmitting material.

[0169] Furthermore, when adhesion is required, the adhesive used must also have high gas barrier properties. This may be selected from commonly known adhesives such as a two-component epoxy adhesive (XNR, manufactured by Nagase ChemteX Corporation) or an encapsulant for organic devices (Moisture Cut, manufactured by MORESCO Corporation), or a method of melting frit glass with a laser in the periphery of the display device may also be used.

[0170] Furthermore, as a measure against moisture, it is effective to introduce a desiccant in the sealing process. Known desiccants include barium oxide and calcium oxide, but there is no particular limitation as long as they have high moisture adsorption performance.

[0171] <Polarizing Layer> The organic EL display device of the present invention preferably further includes a polarizing layer 10, as shown in FIG. 5 . Specifically, a linear polarizing layer and a λ / 4 retardation layer are laminated to suppress reflection of light incident on the display device from the outside. The linear polarizing layer is not particularly limited, but a film obtained by dyeing a polyvinyl alcohol film with iodine and uniaxially stretching the film is often used. The material constituting the λ / 4 retardation layer is also not particularly limited, but a heat-resistant polyimide resin or the like is preferred.

[0172] <Ultraviolet Absorbing Layer> The organic EL display device of the present invention preferably further includes an ultraviolet absorbing layer 11, as shown in FIG. 5 . By including the ultraviolet absorbing layer 11, deterioration of the substrate and the organic EL layer 5 due to ultraviolet rays can be suppressed, thereby improving the reliability of the display device. The ultraviolet absorbing layer 11 is preferably a layer that absorbs light with a wavelength of 320 nm or less, more preferably a layer that absorbs light with a wavelength of 360 nm or less, and even more preferably a layer that absorbs light with a wavelength of 420 nm or less. However, because light with a wavelength of 420 nm or more overlaps with the emission wavelength of blue light used for display, it is preferable that the ultraviolet absorbing layer 11 have high transmittance in the wavelength range of 420 nm or more. This is particularly effective when the organic EL display device of the present invention is used outdoors.

[0173] The ultraviolet absorbing layer 11 preferably contains a resin such as a polyimide resin, a polyamide resin, a polyamideimide resin, a polycarbonate resin, a polyester resin, a polyethersulfone resin, a polyarylate resin, a polyolefin resin, a polyethylene terephthalate resin, a polymethyl methacrylate resin, a polysulfone resin, a polyethylene resin, a polyvinyl chloride resin, an alicyclic olefin polymer resin, an acrylic polymer resin, or a cellulose ester resin. Two or more of these may be contained. Among these, a polyimide resin or a polyamide resin is more preferred.

[0174] The ultraviolet absorbing layer 11 may contain an ultraviolet absorber. Examples of ultraviolet absorbers include benzophenone-based compounds, oxybenzophenone-based compounds, benzotriazole-based compounds, salicylate-based compounds, salicylic acid ester-based compounds, acrylonitrile-based compounds, cyanoacrylate-based compounds, hindered amine-based compounds, triazine-based compounds, nickel complex salt-based compounds, ultrafine titanium oxide particles, metal complex salt-based compounds, and other known polymeric ultraviolet absorbers. Two or more of these may be contained. As the ultraviolet absorber, benzotriazole-based compounds and benzophenone-based compounds are preferred due to their excellent transparency, and benzotriazole-based compounds are more preferred.

[0175] An example of the polymeric ultraviolet absorber is a copolymer of a reactive ultraviolet absorber RUVA-93 manufactured by Otsuka Chemical Co., Ltd. with an acrylic monomer.

[0176] <Method for manufacturing organic EL display device> The method for manufacturing an organic EL display device of the present invention is a method for manufacturing an organic EL display device having a substrate having first electrodes 2, pixel dividing layers 3, and spacers 4 on a base material 1, and further having an organic EL layer 5 and second electrodes 6, the method including a step of processing the pixel dividing layers 3 and the spacers 4 collectively, and the photomask used for the collectively processing is a half-tone photomask having a light-transmitting portion, a light-shielding portion, and a semi-light-transmitting portion.

[0177] An example of the method for manufacturing an organic EL display device of the present invention will be described using the case of manufacturing a top-emission organic EL display device shown in FIG. 5 as an example.

[0178] First, wiring and TFTs 7 are provided on a base material that is a resin film. In addition to the TFT formation processes such as a "gate electrode formation process," a "gate insulating film formation process," a "Si film formation process," and a "source and drain electrode formation process," wiring is also provided to ensure electrical connection, and all of these processes can be formed using known methods.

[0179] Next, the planarization layer 8 is formed by applying it by a slit coating method, followed by heat curing. At this time, contact holes are provided for the purpose of connection with the first electrode 2. If the material used for the planarization layer 8 is photosensitive, this can be achieved by photolithography, and if it is not photosensitive, this can be achieved by general etching using a resist material as a mask. In this way, the substrate 1 is completed.

[0180] Subsequently, AgPdCu and ITO are sequentially formed as a first electrode 2 on the substrate, and then patterned to form the first electrode 2 .

[0181] In the method for manufacturing an organic EL display device of the present invention, pixel division layers 3 are formed in the gaps of first electrodes 2, and spacers 4 are further formed on the pixel division layers. In the process, after applying a photosensitive resin to the entire surface, openings are formed on the first electrodes by photolithography, and the openings become display pixels.

[0182] In the method for manufacturing an organic EL display device of the present invention, the steps of forming pixel division layer 3 and spacers 4 on the pixel division layer are performed in a single process, and the photomask used for single-processing pixel division layer 3 and spacers 4 needs to be a half-tone photomask having a light-transmitting portion, a light-shielding portion, and a semi-light-transmitting portion. Generally, when performing processing using photosensitivity, a full-tone mask consisting of a light-shielding portion and a light-transmitting portion is used. However, the half-tone photomask used in the present invention is a photomask that has a pattern including light-transmitting portion 12 and a light-shielding portion 14, as shown in FIG. 6, for example, and also has a semi-light-transmitting portion 13 between light-transmitting portion 12 and light-shielding portion 14, whose transmittance is lower than that of light-transmitting portion 12 and higher than that of light-shielding portion 14. Exposure using a half-tone photomask makes it possible to form a pattern with a stepped shape after development and heat curing. When the photosensitive resin composition is a positive type, the exposed portions irradiated with activated actinic rays through the light-transmitting portions become alkali-soluble and become openings, and the unexposed portions not irradiated with activated actinic rays through the light-shielding portions become thick films and correspond to the spacers 4, and the halftone exposed portions irradiated with activated actinic rays through the semi-transmitting portions correspond to the pixel dividing layer 3, which has a thickness smaller than that of the spacers 4. Conversely, when the photosensitive resin composition is a negative type, the cured portions irradiated with activated actinic rays through the light-transmitting portions correspond to the spacers 4, and the halftone exposed portions irradiated with activated actinic rays through the semi-transmitting portions correspond to the pixel dividing layer 3.

[0183] As described below, the halftone photomask used in the present invention preferably has a transmittance of 15 to 50% of the transmittance of the transparent portion. When the transmittance of the transparent portion is (% TFT), the transmittance (% THT) of the semi-transparent portion is preferably 15% or more of (% TFT), and more preferably 20% or more. When the transmittance (% THT) of the semi-transparent portion is within the above range, the exposure dose during formation of a cured pattern having a stepped shape can be reduced, thereby shortening the takt time. On the other hand, the transmittance (% THT) of the semi-transparent portion is preferably 50% or less of (% TFT), and more preferably 45% or less. When the transmittance (% THT) of the semi-transparent portion is within the above range, the difference in film thickness between the spacer 4 and the pixel dividing layer 3 can be sufficiently increased, thereby improving the reliability of the display device. Furthermore, if the transmittance of the semi-transparent portion is within the above range, the semi-transparent portion will not receive sufficient exposure to actinic radiation during patterning of the photosensitive resin composition, resulting in a difference in surface roughness between the pixel division layer 3 and the spacer 4 after the development process performed after irradiation with actinic radiation. By varying the absolute value of the difference between the surface roughness Ra1 of the pixel division layer 3 and the surface roughness Ra2 of the spacer 4 in this way, two types of anchoring effects are obtained, as described above, and improved adhesion is achieved. To effectively achieve the anchoring effect, it is preferable to ensure that the difference between Ra1 and Ra2 is 1.0 nm or more. In addition to the transmittance of the semi-transparent portion, both Ra1 and Ra2 can be adjusted by adjusting the resin composition, such as by adding a coloring material or a liquid-repellent material to the photosensitive resin composition.

[0184] In addition to the process using the half-tone photomask described above, it is also possible to adjust the surface roughness by combining several methods, such as mechanical polishing using an abrasive, shot blasting or wet blasting in which an abrasive is sprayed, or dry etching treatment such as plasma treatment or RIE. However, in the present invention, it is necessary to use a half-tone photomask in order to ensure that the absolute value of the difference between Ra1 and Ra2 is 1.0 nm or more.

[0185] The manufacturing method of the organic EL display device of the present invention may include a cleaning step prior to the step of forming the organic EL layer 5 described below. Generally, since contamination from previous steps such as photolithography remains on the surface of the first electrode, wet or dry cleaning is effective. Wet cleaning can be selected from immersion using an organic solvent, surfactant, water, acid solution, alkaline solution, etc., ultrasonic cleaning, boiling cleaning, etc. Dry cleaning can be selected from glow discharge treatment, plasma discharge treatment, UV / ozone treatment, etc. Dry cleaning using an oxygen atmosphere can remove contaminants and adjust the work function. Adjusting the characteristics of the first electrode 2 increases the efficiency of carrier injection from the first electrode 2 to the adjacent organic EL layer 5, which ultimately improves the display device's characteristics, such as luminous efficiency and reliability.

[0186] Next, the method for manufacturing an organic EL display device of the present invention includes a step of forming the organic EL layer 5. Each layer constituting the organic EL layer 5, such as the hole transport layer, the light emitting layer, and the electron transport layer, can be formed by a known method, for example, a mask vapor deposition method or an inkjet method.

[0187] Mask vapor deposition is a method of depositing and patterning an organic compound using a vapor deposition mask. For example, a vapor deposition mask with openings of a desired pattern is placed on the vapor deposition source side of a substrate and vapor deposition is performed. To obtain a highly accurate vapor deposition pattern, it is important to closely contact a highly flat vapor deposition mask with the substrate. Generally, techniques such as applying tension to the vapor deposition mask or using magnets placed on the backside of the substrate to closely contact the vapor deposition mask with the substrate can be used. However, since the generation of particles due to contact between the substrate and the vapor deposition mask can lead to reduced panel yield and degradation of light-emitting elements, it is preferable to keep the spacers 4 in contact with the vapor deposition mask as small and as few as possible.

[0188] Examples of methods for manufacturing a deposition mask include etching, mechanical polishing, sandblasting, sintering, laser processing, the use of photosensitive resins, and electroforming. When a fine pattern is required, it is preferable to use etching or electroforming, which have excellent processing accuracy.

[0189] Mask deposition and inkjet methods are more difficult to use as patterns become finer, so they are required to be used only for the minimum necessary layer, such as the light-emitting layer that determines the emitted color. In this case, by making the hole transport layer and electron transport layer other than the light-emitting layer common to each color, it is possible to form a film over the entire surface, which can improve panel yield and reduce costs.

[0190] The method for manufacturing an organic EL display device of the present invention further includes a step of forming the second electrode 6. As a forming method, a known method can be used, but a vacuum deposition method is preferred because it is easy to avoid deterioration or damage to the underlying organic EL layer 5.

[0191] In the method for manufacturing the organic EL display device of Fig. 5, after the step of forming the second electrode 6, the sealing layer 9, the polarizing layer 10, and the ultraviolet absorbing layer 11 are sequentially laminated. Each layer can be formed by a known method, and the organic EL display device of Fig. 5 is completed in this manner.

[0192] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0193] In the following evaluations, if the test number n is not stated, the evaluation was performed with n=1.

[0194] <Measurement of film thickness of pixel division layer and spacer, taper observation> The film thickness of the pixel division layer and spacer in each example and comparative example was measured from the step between the pixel division layer and the spacer on a patterned substrate (100 mm × 100 mm) using a surface roughness measuring instrument (Surfcom 1400D, manufactured by Tokyo Seimitsu Co., Ltd.) The state of the taper was observed by cutting a cross section of the patterned substrate with a scanning electron microscope (SEM, S-3000N, manufactured by Hitachi High-Technologies Corporation).

[0195] <Surface roughness of pixel division layer and spacer> The surface roughness of the pixel division layer and spacer in each example and comparative example was determined by observing the pixel division layer and spacer of a patterned substrate (100 mm × 100 mm) with an atomic force microscope (AFM, Dimension Icon, manufactured by Bruker Corporation), and the arithmetic mean roughness (Ra) was used. The observation conditions were an RTESP-300 probe, tapping mode, scan size 5 μm square, scan rate 0.1 Hz, and number of sample lines 1024.

[0196] <Observation of Silica Particles Contained in Pixel Dividing Layer> The silica particles contained in the pixel dividing layer in each example and comparative example were observed by transmission electron microscope-energy dispersive X-ray spectroscopy (TEM-EDX) at a magnification of 50,000 times, and then measured using an image analysis particle size distribution analyzer (Mac-View, manufactured by MOUNTECH). That is, 30 silica particles were randomly selected from the TEM image of the cross section of the pixel dividing layer of a patterned substrate (100 mm x 100 mm) (test n: 30), and the major axis, minor axis, and aspect ratio of each particle were measured. Silica particles having a major axis (nm) of 5 to 30 nm and an aspect ratio in the range of 1.0 to 1.5 were defined as component (a). Note that when the minor axis and major axis of a single silica particle were equal in the TEM image, i.e., when the particle was a perfect circle, the diameter was considered to be the major axis. As representative values ​​showing the characteristics of the silica particles corresponding to component (a), the average primary particle diameter, i.e., the average long diameter, was calculated and rounded to the nearest tenth, and the average aspect ratio, i.e., the average aspect ratio of the individual silica particles corresponding to component (a), was calculated and rounded to the nearest tenth, were used.

[0197] The presence or absence of component (a) in each example and comparative example is shown in Table 10, with A indicating the presence of component (a) and B indicating the absence of component (a). Table 11 shows the results of cross-sectional analysis of Examples 23, 24, and 25, in which component (a) was present.

[0198] <Measurement of diffuse reflected light> In the measurement of diffuse reflected light of the substrate in each example and comparative example, the surface of the patterned substrate (100 mm × 100 mm) on which the pixel separation layer and spacers were formed was measured using a spectrophotometer (CM-2600d, manufactured by Konica Minolta Japan, Inc.), and the diffuse reflectance at a wavelength of 550 nm in SCE mode, which removes specular reflected light, was used. The higher the diffuse reflectance, the more specular reflected light was suppressed, and the better the characteristics were judged to be.

[0199] <Adhesion Test> The adhesion test for the organic EL display devices in each Example and Comparative Example was performed by fixing a 5 mm diameter metal cylinder to the center of the surface opposite to the surface on which the light-emitting elements were formed of a substrate (100 mm × 100 mm) as shown in Figure 7. The substrate was repeatedly bent along the cylinder within a range from an embrace angle of 0° (when the substrate was flat) to an embrace angle of 180° (when the substrate was folded back on itself), and the bent portion was then observed with an optical microscope. When peeling occurred after 1 to 100 bending cycles, the adhesion was judged to be poor (characteristic C); when peeling occurred after 101 to 1000 bending cycles, the adhesion was judged to be poor (characteristic B); and when peeling occurred after 1001 or more bending cycles, the adhesion was judged to be high (characteristic A). The test was performed 10 times (test number n: 10), and the result with the fewest number of bending cycles until peeling occurred was used.

[0200] <Weather Resistance Reliability Test> In the weather resistance reliability test for the organic EL display devices in each of the Examples and Comparative Examples, the state of the organic EL display devices fabricated in each of the Examples and Comparative Examples described below after being left at room temperature of 23°C and humidity of 45% for 24 hours was confirmed. Ten display devices were used in the test (test number n: 10). If no corrosion was observed in the second electrode, the weather resistance reliability was judged to be good (A), and if corrosion was observed in even one of the second electrodes, the presence of a pinhole was judged to be (B).

[0201] <Electrical Reliability Test> In the electrical reliability test of the organic EL display device in each example and comparative example, a voltage of 5 V was applied between two adjacent stripe-shaped first electrodes in the organic EL display device fabricated in each example and comparative example described below, and the current value was measured. A source meter (2400, manufactured by Keithley Instruments Inc.) was used for the measurement, and a smaller current value was determined to indicate a smaller leakage current and better characteristics. The test was conducted at 20 locations (n=20), and the average value of 10 measurements, excluding five large and five small measurement results, was used.

[0202] <Light Emitting Characteristics Test> The light emitting characteristics test of the organic EL display device in each example and comparative example was carried out by applying 10 mA / cm to one light emitting element selected from a pair of intersecting first and second electrodes in the organic EL display device produced in each example and comparative example described below. ２ The voltage and luminance were measured when a current of 1000 kJ / s was applied. A source meter (2400, manufactured by Keithley Instruments, Inc.) was used to measure the voltage, and a spectroradiometer (CS-1000, manufactured by Konica Minolta, Inc.) was used to measure the luminance.

[0203] <Design of First Electrode and Halftone Photomask> The designs of the first electrode and halftone photomask in each example and comparative example are shown in FIG. 6 . As shown in FIG. 6 a, 100 first electrodes 2 were fabricated in the center of a substrate 1 (100 mm × 100 mm) in a stripe pattern with a line width of 60 μm, a 100 μm pitch, and a length of 10 mm. In other words, the exposed portion of the substrate 1 was 40 μm wide. In contrast, for the positive-tone halftone photomask b, the line widths were adjusted at a 100 μm pitch so that the light-shielding portions 14 became spacers and the semi-transmitting portions 13 became pixel division layers. For the negative-tone halftone photomask c, the line widths I and II were adjusted so that the light-transmitting portions 12 became spacers and the semi-transmitting portions 13 became pixel division layers. In both cases, the pixel division layers and spacers were aligned as shown in FIG. 6 so that they were positioned in the gaps in the first electrodes. In the completed substrate, line width I corresponds to the interface where the pixel dividing layer and the organic EL layer contact, and line width II corresponds to the interface where the spacer and the organic EL layer contact.

[0204] <Preparation of Photosensitive Resin Compositions> The photosensitive resin compositions R-1 to R-15 used in each of the Examples and Comparative Examples were prepared as follows. Note that the names of the compounds used, for which abbreviations are used, are shown below. BAHF: 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane BFE: 1,2-bis(4-formylphenyl)ethane BIP-PHBZ: 4,4',4"-methylidene trisphenol (manufactured by Asahi Organic Chemicals Co., Ltd.) BYK-333: Silicone surfactant "BYK" (registered trademark) 333 (manufactured by BYK-Chemie Co., Ltd.) DAE: Diaminodiphenyl ether DFA: N,N-dimethylformamide dimethyl acetal DMAA: N,N-dimethylacrylamide DPCA-60: Caprolactone 6-mol modified dipentaerythritol hexaacrylate (hexafunctional acrylate having six pentyleneoxy chains, manufactured by Nippon Kayaku Co., Ltd.) EL: Ethyl lactate FAMAC-6: 2-(perfluorohexyl)ethyl methacrylate GBL: γ-butyrolactone GMA: glycidyl methacrylate; HA: hydroxy group-containing diamine compound; HMOM-TPHAP: a compound having a phenolic hydroxyl group and having substituents with a molecular weight of 40 or more at both ortho positions of the phenolic hydroxyl group, as shown in the chemical formula below (manufactured by Honshu Chemical Industry Co., Ltd.).

[0205]

[0206] KBM-403: 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) MAP: 3-aminophenol; metaaminophenol MBA: 3-methoxy-n-butyl acetate MEK-ST-40: Silica particle dispersion (manufactured by Nissan Chemical Industries, Ltd.). The solvent is methyl ethyl ketone MEK-ST-L: Silica particle dispersion (manufactured by Nissan Chemical Industries, Ltd.). The solvent type was methyl ethyl ketone. MeTMS: methyltrimethoxysilane. NA: 5-norbornene-2,3-dicarboxylic anhydride; nadic anhydride. TMOS: tetramethoxysilane. NCI-831: "ADEKA ARCLES" (registered trademark) NCI-831 (manufactured by ADEKA Corporation). NMP: N-methyl-2-pyrrolidone. ODPA: bis(3,4-dicarboxyphenyl)ether dianhydride; oxydiphthalic dianhydride. OSCAL-1421: silica particle dispersion (manufactured by JGC Catalysts and Chemicals Industries, Ltd.).The solvent used was isopropyl alcohol. PGME: Propylene glycol monomethyl ether PGMEA: Propylene glycol monomethyl ether acetate PhTMS: Phenyltrimethoxysilane S0100CF: Irgaphor Black (registered trademark) S0100CF SiDA: 1,3-bis(3-aminopropyl)tetramethyldisiloxane S-20000: "SOLSPERSE" (registered trademark) 20000 (polyether-based dispersant, manufactured by Lubrizol) TMSSucA: 3-trimethoxysilylpropylsuccinic anhydride TrisP-PA: 1,1-bis(4-hydroxyphenyl)-1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethane (manufactured by Honshu Chemical Industry Co., Ltd.) WR-301: "ADEKA ARKLS" (registered trademark) WR-301 (manufactured by ADEKA Corporation) Karenz MOI-BM: 2-(0-[1'-methylpropylideneamino]carboxyamino)ethyl methacrylate Bisphenol AF: 2,2-bis(4-hydroxyphenyl)hexafluoropropane (manufactured by Central Glass Co., Ltd.) 6FDA: 2,2-(3,4-dicarboxyphenyl)hexafluoropropane dianhydride; 4,4'-hexafluoropropane-2,2-diyl-bis(1,2-phthalic anhydride) Pigment dispersant 1: Pigment dispersant 1 (solids content 100% by weight) disclosed in Synthesis Example 2 of JP 2020 / 70352 A. A polymeric dispersant having a linear polyalkyleneamine structure and a polyether-based polymer chain.

[0207] Synthesis Example 1 Synthesis of Polyimide Resin (PI-1) In a dry nitrogen stream, 31.13 g (0.085 mol; 77.3 mol% relative to all structural units derived from amines and derivatives), 1.24 g (0.0050 mol; 4.5 mol% relative to all structural units derived from amines and derivatives) of SiDA, 2.18 g (0.020 mol; 18.2 mol% relative to all structural units derived from amines and derivatives) of MAP as an end-capping agent, and 150.00 g of NMP were weighed and dissolved in a three-neck flask. A solution of 31.02 g (0.10 mol; 100 mol% relative to all structural units derived from carboxylic acids and derivatives) of ODPA dissolved in 50.00 g of NMP was added thereto, and the mixture was stirred at 20°C for 1 hour, and then at 50°C for 4 hours. Thereafter, 15 g of xylene was added, and the mixture was stirred at 150°C for 5 hours while azeotropically distilling water with the xylene. After completion of the reaction, the reaction solution was poured into 3 L of water, and the deposited solid precipitate was obtained by filtration. The obtained solid was washed three times with water and then dried in a vacuum dryer at 80°C for 24 hours to obtain polyimide resin (PI-1). The weight average molecular weight (Mw) of the obtained polyimide resin (PI-1) was 27,000, and the acid equivalent was 350.

[0208] Synthesis Example 2: Synthesis of HA In a three-neck flask, 18.31 g (0.05 mol) of BAHF, 17.42 g (0.3 mol) of propylene oxide, and 100 mL of acetone were weighed and dissolved. A solution of 20.41 g (0.11 mol) of 3-nitrobenzoyl chloride dissolved in 10 mL of acetone was added dropwise. After the addition was complete, the reaction was allowed to proceed at -15°C for 4 hours, and then the temperature was returned to room temperature. The precipitated white solid was collected by filtration and dried under vacuum at 50°C. 30 g of the resulting solid was placed in a 300 mL stainless steel autoclave and dispersed in 250 mL of 2-methoxyethanol, followed by the addition of 2 g of 5% palladium-carbon. Hydrogen was introduced via a balloon, and the mixture was allowed to react at room temperature for 2 hours. After 2 hours, it was confirmed that the balloon was no longer deflating. After the reaction was completed, the catalyst palladium compound was removed by filtration, and the reaction mixture was concentrated by distillation under reduced pressure to obtain a hydroxyl group-containing diamine compound (HA) having the following structure.

[0209]

[0210] <Synthesis Example 3 Synthesis of polyimide precursor resin (PIP-1)> In a dry nitrogen stream, 44.42 g (0.10 mol; 100 mol% relative to the structural units derived from all carboxylic acids and their derivatives) of 6FDA was weighed and dissolved in a three-necked flask. 150 g of NMP was dissolved in 14.65 g (0.040 mol; 32.0 mol% relative to the structural units derived from all amines and their derivatives) of BAHF in 50 g of NMP, 18.14 g (0.030 mol; 24.0 mol% relative to the structural units derived from all amines and their derivatives), and 1.24 g (0.0050 mol; 4.0 mol% relative to the structural units derived from all amines and their derivatives) of SiDA. The mixture was stirred at 20 ° C. for 1 hour, and then stirred at 50 ° C. for 2 hours. Next, a solution of 5.46 g (0.050 mol; 40.0 mol% based on the total structural units derived from amines and their derivatives) of MAP dissolved in 15 g of NMP was added as an end-capping agent, and the mixture was stirred at 50°C for 2 hours. Subsequently, a solution of 23.83 g (0.20 mol) of DFA dissolved in 15 g of NMP was added. After the addition was completed, the mixture was stirred at 50°C for 3 hours. After the reaction was completed, the reaction solution was cooled to room temperature and then poured into 3 L of water, and the resulting solid precipitate was obtained by filtration. The obtained solid was washed three times with water and then dried in a vacuum dryer at 80°C for 24 hours to obtain polyimide precursor resin (PIP-1). The weight average molecular weight (Mw) of the obtained polyimide precursor resin (PIP-1) was 20,000 and the acid equivalent was 450.

[0211] Synthesis Example 4: Synthesis of Polyimide Precursor Resin (PIP-2) Under a dry nitrogen stream, 21.2 g (0.035 mol) of HA obtained in Synthesis Example 2, 7.0 g (0.035 mol) of DAE, and 1.2 g (0.005 mol) of SiDA were dissolved in 400 g of NMP. 31.0 g (0.10 mol) of ODPA was added to this solution along with 50 g of NMP, and the mixture was stirred at 40°C for 1 hour. 5.5 g (0.050 mol) of MAP was then added and the mixture was stirred at 40°C for 1 hour. Furthermore, a solution of 8.3 g (0.07 mol) of DFA dissolved in 10 g of NMP was added. After the addition was completed, the mixture was stirred at 40°C for 3 hours. After the stirring was completed, the solution was cooled to room temperature, and then the solution was poured into 3 L of water to obtain a white precipitate. The precipitate was collected by filtration, washed three times with water, and then dried in a vacuum dryer at 50°C for 72 hours to obtain an alkali-soluble resin (PIP-2) consisting of a polyimide precursor resin with an acid equivalent of 275 g / mol.

[0212] Synthesis Example 5: Synthesis of Polyimide Precursor Resin (PIP-3) An alkali-soluble resin (PIP-3) made of a polyimide precursor resin having an acid equivalent of 329 g / mol was obtained in the same manner as in Synthesis Example 4, except that the amount of DFA added was set to 13.1 g (0.11 mol).

[0213] Synthesis Example 6: Synthesis of Polyimide Precursor Resin (PIP-4) An alkali-soluble resin (PIP-4) made of a polyimide precursor resin having an acid equivalent of 366 g / mol was obtained in the same manner as in Synthesis Example 4, except that the amount of DFA added was set to 16.7 g (0.14 mol).

[0214] Synthesis Example 7: Synthesis of Polybenzoxazole Resin (PBO-1) In a 500 mL round-bottom flask filled with toluene and equipped with a Dean-Stark water separator and a condenser, 34.79 g (0.095 mol; 95.0 mol% relative to all structural units derived from amines and their derivatives) of BAHF, 1.24 g (0.0050 mol; 5.0 mol% relative to all structural units derived from amines and their derivatives) of SiDA, and 75.00 g of NMP were weighed and dissolved. To this, a solution of 19.06 g (0.080 mol; 66.7 mol% relative to all structural units derived from carboxylic acids and their derivatives) of BFE and 6.57 g (0.040 mol; 33.3 mol% relative to all structural units derived from carboxylic acids and their derivatives) of NA as an end-capping agent was added to 25.00 g of NMP, and the mixture was stirred at 20°C for 1 hour, followed by stirring at 50°C for 1 hour. The mixture was then heated and stirred at 200°C or higher for 10 hours under a nitrogen atmosphere to carry out a dehydration reaction. After completion of the reaction, the reaction solution was poured into 3 L of water, and the resulting solid precipitate was collected by filtration. The resulting solid was washed three times with water and then dried in a vacuum dryer at 80°C for 24 hours to obtain a polybenzoxazole resin (PBO-1). The resulting polybenzoxazole resin (PBO-1) had a weight average molecular weight (Mw) of 25,000 and an acid equivalent of 330.

[0215] Synthesis Example 8: Synthesis of Polybenzoxazole Precursor Resin (PBOP-1) In a 500 mL round-bottom flask filled with toluene and equipped with a Dean-Stark water separator and a condenser, 34.79 g (0.095 mol; 95.0 mol% relative to all structural units derived from amines and their derivatives), 1.24 g (0.0050 mol; 5.0 mol% relative to all structural units derived from amines and their derivatives), and 70.00 g of NMP were weighed and dissolved. A solution of 19.06 g (0.080 mol; 66.7 mol% relative to all structural units derived from carboxylic acids and their derivatives) of BFE dissolved in 20.00 g of NMP was added thereto, and the mixture was stirred at 20° C. for 1 hour, and then at 50° C. for 2 hours.

[0216] Next, a solution of 6.57 g (0.040 mol; 33.3 mol% based on the total structural units derived from carboxylic acids and their derivatives) of NA dissolved in 10 g of NMP as an end-capping agent was added, and the mixture was stirred at 50°C for 2 hours. The mixture was then stirred at 100°C for 2 hours under a nitrogen atmosphere. After completion of the reaction, the reaction solution was poured into 3 L of water, and the resulting solid precipitate was collected by filtration. The resulting solid was washed three times with water and then dried in a vacuum dryer at 80°C for 24 hours to obtain a polybenzoxazole precursor resin (PBOP-1). The weight-average molecular weight (Mw) of the resulting polybenzoxazole precursor resin (PBOP-1) was 20,000, and the acid equivalent was 330.

[0217] Synthesis Example 9: Synthesis of Polysiloxane Resin Solution (PS-1) A three-neck flask was charged with 23.84 g (35 mol%) of MeTMS, 49.57 g (50 mol%) of PhTMS, 3.81 g (5 mol%) of TMOS, and 76.36 g of PGMEA. Air was flowed into the flask at 0.05 L / min, and the mixed solution was heated to 40 °C in an oil bath while stirring. While further stirring the mixed solution, an aqueous phosphoric acid solution prepared by dissolving 0.271 g of phosphoric acid in 28.38 g of water was added dropwise over 10 minutes. After completion of the dropwise addition, the mixture was stirred at 40 °C for 30 minutes to hydrolyze the silane compound. After completion of the hydrolysis, a solution prepared by dissolving 13.12 g (10 mol%) of TMSSucA in 8.48 g of PGMEA was added. The bath temperature was then raised to 70°C and the mixture was stirred for 1 hour, after which the bath temperature was subsequently raised to 115°C. Approximately 1 hour after the start of the temperature increase, the internal temperature of the solution reached 100°C, after which the mixture was heated and stirred for 2 hours (internal temperature: 100-110°C). After 2 hours of heating and stirring, the resulting resin solution was cooled in an ice bath, and then 2% by weight of anion exchange resin and cation exchange resin were added to the resin solution, followed by stirring for 12 hours. After stirring, the anion exchange resin and cation exchange resin were removed by filtration, yielding a polysiloxane resin solution (PS-1). The resulting polysiloxane resin had a weight average molecular weight (Mw) of 4,200 and a carboxylic acid equivalent (acid equivalent) of 700 g / mol.

[0218] Synthesis Example 10: Synthesis of Photosensitizer (Quinonediazide Compound b-1) Under a dry nitrogen stream, 21.22 g (0.05 mol) of TrisP-PA (trade name, manufactured by Honshu Chemical Industry Co., Ltd.) and 36.27 g (0.135 mol) of 5-naphthoquinonediazide sulfonyl chloride were dissolved in 450 g of 1,4-dioxane and the solution was allowed to cool to room temperature. 15.18 g of triethylamine mixed with 50 g of 1,4-dioxane was added dropwise thereto so that the temperature in the system did not exceed 35°C. After the dropwise addition, the mixture was stirred at 30°C for 2 hours. The triethylamine salt was filtered, and the filtrate was poured into water. The precipitate was then collected by filtration. This precipitate was dried in a vacuum dryer to obtain a photosensitizer (quinonediazide compound b-1) having the following structure.

[0219]

[0220] <Preparation of Salt-Forming Compound d-1> 9.25 g (0.018 mol) of C.I. Basic Blue 7 as a basic dye and 200 g of pure water were added to a separable flask and stirred at 60°C for 30 minutes. An aqueous solution prepared by dissolving 11.50 g (0.019.8 mol) of C.I. Acid Red 52 as an acid dye in 120 g of pure water was added, and the mixture was stirred at 60°C for 60 minutes. Thereafter, heating was stopped and the mixture was stirred and cooled to room temperature. After cooling to room temperature, the reaction solution was filtered to obtain a purple solid. This solid was dried under reduced pressure at 60°C for 8 hours to obtain salt-forming compound d-1.

[0221] <Preparation of Salt-Forming Compound d-2> A salt-forming compound d-2 was obtained in the same manner as in d-1, except that CI Basic Blue 26 was used instead of CI Basic Blue 7 as the basic dye.

[0222] <Preparation of Pigment Dispersion 1> 15.00 g of S-20000, a pigment dispersant having a basic group, was added to 742.39 g of PGMEA, which was the solvent component, followed by 2.70 g of a PGMEA solution containing 1.00 wt% 4-methylbenzenesulfonic acid. The mixture was then stirred for 1 hour at atmospheric pressure and a liquid temperature of 25°C, and then allowed to stand for an additional 6 hours to allow the basic group of S-20000 and the sulfo group of 4-methylbenzenesulfonic acid to form a salt in advance. Furthermore, 149.91 g of an alkali-soluble resin solution (a resin solution (solids content: 30.0 wt%) obtained by dissolving the above-mentioned PIP-1 in PGMEA to a solids content of 30 wt%) was added and stirred for 30 minutes. Then, 90.00 g of a benzodifuranone-based black pigment represented by the following structure was added and stirred for 20 minutes to obtain a preliminary dispersion. The preliminary dispersion was sent to a bead mill filled with 75% by volume of 0.4 mm diameter zirconia beads ("Treceram" (registered trademark), manufactured by Toray Industries, Inc.) as dispersion media, and a dispersion treatment was performed once. Subsequently, a wet media dispersion treatment was performed using a circulation system. After 30 minutes had elapsed, an appropriate amount of the pigment dispersion was sampled by withdrawing it from the discharge port of the disperser into a glass bottle every 10 minutes of dispersion treatment time. The sample was placed in a laser diffraction / scattering particle size distribution analyzer (UPA150, manufactured by Microtrac) and the average dispersed particle diameter was measured. The pigment dispersion that had an average dispersed particle diameter of 150±10 nm as a median diameter D50 (cumulative 50% volume average diameter) and 300±30 nm as a median diameter D90 (cumulative 90% volume average diameter) 30 minutes after sampling was designated "Pigment Dispersion 1."

[0223]

[0224] <Preparation of Pigment Dispersion Liquid 2> "Pigment Dispersion Liquid 2" was prepared using the same procedure as for "Pigment Dispersion Liquid 1", except that PIP-1 was dissolved in MBA instead of PGMEA.

[0225] Preparation of Pigment Dispersion 3: 200 g of zirconium nitride particles (ZrN, manufactured by Nisshin Engineering Inc.) produced by a thermal plasma method, 50 g of polyimide precursor resin (PIP-1), and 1,000 g of γ-butyrolactone (GBL) were charged into a tank and stirred with a homomixer for 20 minutes to obtain a preliminary dispersion. The resulting preliminary dispersion was fed into a disperser (Ultra Apex Mill, manufactured by Hiroshima Metal & Machinery Co., Ltd.) equipped with a centrifugal separator filled with 75% by volume of 0.05 mm diameter zirconia beads, and dispersion was carried out at a rotation speed of 10 m / s for 3 hours to obtain Pigment Dispersion 3 with a solids concentration of 20 wt % and a colorant / resin (weight ratio) of 80 / 20. The composition is shown in Table 1.

[0226]

[0227] <Preparation of Pigment Dispersion Liquid 4> Pigment Dispersion Liquid 4 was obtained in the same manner as in the preparation of Pigment Dispersion Liquid 3, except that the alkali-soluble resin added was PIP-2.

[0228] <Preparation of Pigment Dispersion Liquid 5> Pigment Dispersion Liquid 5 was obtained in the same manner as in the preparation of Pigment Dispersion Liquid 3, except that the alkali-soluble resin added was PIP-3.

[0229] <Preparation of Pigment Dispersion Liquid 6> Pigment Dispersion Liquid 6 was obtained in the same manner as in the preparation of Pigment Dispersion Liquid 3, except that the alkali-soluble resin added was PIP-4.

[0230] <Preparation of Pigment Dispersion Liquid 7> 30.00 g of pigment dispersant 1 was added to 770.00 g of PGMEA solvent, and the mixture was stirred for 5 minutes. 100.00 g of ZCR-1569H was then added and stirred for 30 minutes. Furthermore, 100.00 g of S0100CF was added as component (b), and the mixture was stirred for 30 minutes to obtain a pre-stirred liquid. The pre-stirred liquid was sent to a vertical bead mill filled with grinding media (zirconium oxide: hafnium oxide: yttrium oxide: aluminum oxide = weight ratio 93.3: 1.5: 4.9: 0.3, manufactured by Toray Industries, Inc.) made of a 0.4 mmφ composite oxide at a filling rate of 75% by volume, and the first wet media dispersion treatment was carried out using a circulation system at a peripheral speed of 8 m / s for 3 hours. The solution was then sent to a vertical bead mill containing a vessel filled with 0.05 mmφ composite oxide milling media (zirconium oxide:hafnium oxide:yttrium oxide:aluminum oxide = weight ratio 93.3:1.5:4.9:0.3, manufactured by Toray Industries, Inc.) at a filling rate of 75 volume %, and subjected to a second wet media dispersion treatment using a circulation system at a peripheral speed of 9 m / s for 6 hours. Thereafter, the mixture was filtered through a 0.8 μm diameter filter to prepare Pigment Dispersion Liquid 1 with a solids content of 20.00 wt %. The blend weights of the raw materials are shown in Table 2.

[0231]

[0232] <Preparation of Photosensitive Resin Composition R-1> Under yellow light, (A) the polyimide precursor resin PI-1 obtained in Synthesis Example 1 as an alkali-soluble resin, (B) the compound b-1 obtained in Synthesis Example 10 as a photosensitizer, (D) among the coloring materials, compound d-1 as a salt-forming compound consisting of an acid dye and a basic dye, C.I. Solvent Blue 45 as a nonionic dye d-3, a thermochromic compound f-1 (BIP-PHBZ) represented by the following structure, and other additives such as a thermal crosslinker g-1 (HMOM-TPHAP), a compound h-1 (bisphenol AF) having a phenolic hydroxyl group, and an adhesion improver i-1 (KBM-403) were added in the amounts shown in Table 3 to a solvent (C) of γ-butyrolactone (GBL) and ethyl lactate (EL) in a weight ratio of 1:1, and the mixture was stirred and dissolved to prepare a positive photosensitive resin composition R-1.

[0233]

[0234]

[0235] <Preparation of Photosensitive Resin Compositions R-2 to R-6> R-2 to R-6 were prepared according to the compositions shown in Table 3 in the same manner as in the preparation of R-1.

[0236] <Preparation of Photosensitive Resin Composition R-7> Under yellow light, 0.20 g of NCI-831, a photosensitizer, was added to 13.01 g of PGMEA and stirred for 3 minutes to dissolve. To this mixture were added 4.28 g of alkali-soluble polyimide resin solution A (a resin solution obtained by dissolving PI-1 in PGMEA to a solids content of 30 wt %) and 1.02 g of alkali-soluble cardo resin solution A (a PGMEA solution of an alkali-soluble cardo resin having an amine value of 0 (mg KOH / g), a resin acid value of 90 (mg KOH / g), a solids content of 44.2 wt %, and having carboxyl groups as alkali-soluble groups, "ADEKA ARKLS" (registered trademark) WR-301 (manufactured by ADEKA Corporation)), and 0.99 g of DPCA-60, a compound having two or more radically polymerizable groups, was added and stirred to obtain a prepared solution. This prepared solution was mixed with 10.50 g of pigment dispersion 1 sampled from the supernatant liquid in the glass bottle and stirred for 30 minutes to obtain negative-tone photosensitive resin composition R-7. The blending amounts of the raw materials are shown in Table 4.

[0237]

[0238] <Preparation of Photosensitive Resin Composition R-8> Negative photosensitive resin composition R-8 was prepared in the same manner as for R-7, except that alkali-soluble polyimide resin solution B (a resin solution obtained by dissolving PI-1 using MBA to give a solids content of 30% by weight) was used instead of alkali-soluble polyimide resin solution A, and pigment dispersion liquid 2 was used instead of pigment dispersion liquid 1. The blending amounts of the raw materials are shown in Table 4.

[0239] Synthesis Example 11: Synthesis of Liquid-Repellent Materials (e-1) and (e-2) 100 parts by weight of cyclohexanone was added to a 1000 mL reaction vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen gas inlet, and the temperature was raised to 110°C under a nitrogen gas atmosphere. The temperature of cyclohexanone was maintained at 110°C, and the monomer mixed solution shown in Table 5 was added dropwise at a constant rate using the dropping funnel over a period of 2 hours to prepare each monomer solution. After completion of the addition, the monomer solution was heated to 115°C and allowed to react for 2 hours to obtain liquid-repellent materials (e-1) and (e-2).

[0240]

[0241] Synthesis Example 12: Synthesis of Phenolic Resin (j-1) Under a dry nitrogen stream, 108.0 g (1.00 mol) of m-cresol, 75.5 g of a 37 wt % aqueous formaldehyde solution (0.93 mol of formaldehyde), 0.63 g (0.005 mol) of oxalic acid dihydrate, and 264 g of methyl isobutyl ketone were charged, and the flask was then immersed in an oil bath. The reaction solution was refluxed for 4 hours while undergoing a polycondensation reaction. The temperature of the oil bath was then raised over 3 hours, after which the pressure inside the flask was reduced to 4.0 kPa to 6.7 kPa, the volatiles were removed, and the dissolved resin was cooled to room temperature to obtain novolac phenolic resin (j-1). GPC analysis revealed that the weight-average molecular weight was 3,500.

[0242] <Preparation of Photosensitive Resin Compositions R-9 and R-10> Under yellow light, the components were mixed in the blending ratios shown in Table 6 and dissolved by sufficient stirring at room temperature. The resulting solution was then filtered through a filter with a pore size of 1 μm to obtain positive-type photosensitive resin compositions R-9 and R-10.

[0243]

[0244] <Preparation of Photosensitive Resin Composition R-11> To 93.8 g of Pigment Dispersion 3, 50.5 g of alkali-soluble resin (PIP-1), 17.0 g of quinone diazide compound (b-1) as a photoacid generator, 13.6 g of phenol compound (h-1, bisphenol AF), 0.2 g of silicone surfactant (BYK-333), 105.0 g of GBL, and 720.0 g of PGME were added to obtain a positive photosensitive resin composition R-11 having a total solids concentration of 10 wt% and a pigment / resin (weight ratio) of 15 / 85. The composition is shown in Table 7.

[0245]

[0246] <Preparation of Photosensitive Resin Composition R-12> Positive photosensitive resin composition R-12 was obtained in the same manner as in R-11, except that the pigment dispersion added was changed from Pigment Dispersion 3 to Pigment Dispersion 4, and the alkali-soluble resin was changed from PIP-1 to PIP-2. The composition is shown in Table 7.

[0247] <Preparation of Photosensitive Resin Composition R-13> Positive photosensitive resin composition R-13 was obtained in the same manner as in R-11, except that Pigment Dispersion 5 was used instead of Pigment Dispersion 3 as the pigment dispersion and PIP-3 was used as the alkali-soluble resin instead of PIP-1. The composition is shown in Table 7.

[0248] <Preparation of Photosensitive Resin Composition R-14> Positive photosensitive resin composition R-14 was obtained in the same manner as in R-11, except that Pigment Dispersion 3 was replaced with Pigment Dispersion 6 as the pigment dispersion and PIP-1 was replaced with PIP-4 as the alkali-soluble resin. The composition is shown in Table 7.

[0249] <Preparation of Photosensitive Resin Composition R-15> Under yellow light, (A) 10.0 g of polyimide precursor resin (PIP-1) as an alkali-soluble resin, (B) 1.2 g of f-1 as a photosensitizer, and (C) 32.0 g of PGME and 8.0 g of GBL as organic solvents were added. The resulting solution was then filtered through a 0.45 μmφ filter to obtain a positive-type photosensitive resin composition R-15.

[0250] <Preparation of Photosensitive Resin Composition R-16> Under yellow light, 0.38 g of OXE03 as a photopolymerization initiator was added to a mixed solvent of 8.50 g of MBA and 16.16 g of PGMEA and stirred for 10 minutes to dissolve. To this was added 1.88 g of MEK-ST-40 as component (a), a silica particle dispersion, and stirred for 10 minutes to dissolve. Next, 4.61 g of ZAH-106, 0.45 g of TR4020G, 0.38 g of DPCA-60, and 0.97 g of GA-5060P were added and stirred for 30 minutes to obtain a transparent preparation. 16.69 g of Pigment Dispersion 7 was mixed with this preparation and stirred for 30 minutes to prepare a negative-type photosensitive resin composition R-16 with a solids content of 15.00 wt %. The blend weights of each raw material are shown in Table 8.

[0251]

[0252] <Preparation of Photosensitive Resin Composition R-17> In the same manner as in the preparation of R-16, negative photosensitive resin composition R-17 was prepared using OSCAL-1421 instead of MEK-ST-40 in the amounts shown in Table 8. The blending weights of each raw material are shown in Table 8.

[0253] <Preparation of Photosensitive Resin Composition R-18> Negative photosensitive resin composition R-18 was prepared in the same manner as in the preparation of R-16, except that MEK-ST-L was used instead of MEK-ST-40, in the amounts shown in Table 8. The blending weights of each raw material are shown in Table 8.

[0254] <Examples 1 to 25, Comparative Examples 1 to 3> In each of the examples and comparative examples, the surface roughness of the pixel division layer and spacer, the diffuse reflected light of the substrate, the adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated as follows.

[0255] First, AgPdCu (100 nm) and crystalline ITO (10 nm) were deposited sequentially as a first electrode in the center of a 100 mm x 100 mm PET substrate using a vacuum sputtering method, and then etched into 100 stripes with a line width of 60 μm, a 100 μm pitch, and a length of 10 mm. In other words, the exposed portion of the substrate was 40 μm wide. A photosensitive resin composition according to each example and comparative example listed in Table 9 was applied to the substrate using a spin coating method, and then prebaked on a hot plate at 100 °C for 2 minutes to form a film.

[0256] This film was exposed to UV light through the halftone photomask shown in Table 9, and then developed with a 2.38% TMAH aqueous solution. If it was a negative type, only the unexposed parts were dissolved, and if it was a positive type, only the exposed parts were dissolved, and then rinsed with pure water to obtain a pattern. The film was then cured for 60 minutes in an oven at 250°C under a nitrogen atmosphere to obtain a substrate with a pixel division layer and spacer pattern. By adjusting the rotation speed in the spin coating method, the film thickness of the pixel division layer was 1.5 μm and the film thickness of the spacer was 1.5 μm in all examples and comparative examples.

[0257] In Comparative Example 1, the pixel division layer and spacers were fabricated separately using a photomask without a semi-transparent portion, commonly known as a full-tone mask. That is, after coating the pixel division layer, pre-baking, exposing, developing, and curing, the process of coating the spacers, pre-baking, exposing, developing, and curing was carried out. In Comparative Example 3, after curing, a plasma treatment device (SPC-100B+H, manufactured by Hitachi High-Technologies Corporation) was used to perform a roughening treatment in RIE mode using oxygen gas at 1000 W for 60 seconds.

[0258] In this state, the surface roughness of the pixel dividing layer and the spacer and the diffuse reflected light of the substrate were evaluated. The results are shown in Table 10.

[0259] Next, an organic EL layer was formed on the entire surface of the patterned substrate by vacuum deposition. －３The pressure was set to 0.1 Pa or less, and the substrate was rotated relative to the evaporation source during evaporation. First, compound (HT-1) was evaporated to a thickness of 10 nm as a hole injection layer, and compound (HT-2) was evaporated to a thickness of 50 nm as a hole transport layer. Next, as an emitting layer, compound (GH-1) as a host material and compound (GD-1) as a dopant material were evaporated to a thickness of 40 nm so that the doping concentration was 10% by volume. Next, compound (ET-1) and LiQ were laminated to a thickness of 40 nm at a volume ratio of 1:1 as an electron transport layer. The hole injection layer, hole transport layer, emitting layer, and electron transport layer thus far are referred to as a first emitting unit.

[0260] Thereafter, LiQ was vapor-deposited to a thickness of 2 nm as an electron injection layer. The structure of the compound used in the organic EL layer is shown below.

[0261]

[0262]

[0263] Furthermore, 20 stripe-shaped second electrodes, each 400 μm wide, 500 μm pitch, and 10 mm long, were deposited to a thickness of 10 nm by vapor deposition of Mg and Ag at a volume ratio of 10:1 so as to intersect with the first electrodes. The film thickness referred to here is the value displayed on a quartz crystal oscillation film thickness monitor.

[0264] In this way, an organic EL display device was completed, which had 100 first electrodes, 20 second electrodes, and 200 light-emitting elements where the electrodes intersect. A schematic diagram of the organic EL display device of this example is shown in Figure 8, and a schematic diagram of a light-emitting element without the organic EL layer is shown in Figure 9. The organic EL display device was then evaluated for adhesion, weather resistance reliability, and electrical reliability. The results are shown in Table 10.

[0265]

[0266]

[0267]

[0268]

[0269]

[0270] Example 26 An organic EL display device was produced in the same manner as in Example 1, except that in the first light-emitting unit, LiQ was not used in the electron transport layer, and only compound (ET-1) was used. The adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0271] Example 27 An organic EL display device was produced in the same manner as in Example 1, except that in the first light-emitting unit, LiQ was not used in the electron transport layer, and only compound (ET-2) was used. The adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0272] Example 28 An organic EL display device was produced in the same manner as in Example 1, except that in the first light-emitting unit, LiQ was not used in the electron transport layer, and only compound (ET-3) was used. The adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0273] Example 29 An organic EL display device was produced in the same manner as in Example 1, except that in the first light-emitting unit, LiQ was not used in the electron transport layer, and only compound (ET-4) was used. The adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0274] Example 30 A patterned substrate was obtained in the same manner as in Example 1, and then a first light-emitting unit was laminated as an organic EL layer. Thereafter, on the first light-emitting unit, compound (ET-1) and metallic Li as a dopant material were vapor-deposited to a thickness of 10 nm as an n-type charge generation layer so that the vapor deposition rate ratio of compound (ET-1):Li was 99:1, and then compound (HT-1) was vapor-deposited to a thickness of 10 nm as a p-type charge generation layer.

[0275] Following the charge generation layer, an organic EL layer similar to that of the first light-emitting unit was again formed to form a tandem structure. Then, LiQ was vapor-deposited to a thickness of 2 nm as an electron injection layer. Furthermore, 20 stripe-shaped second electrodes, each with a line width of 400 μm, a pitch of 500 μm, and a length of 10 mm, were vapor-deposited to a thickness of 10 nm with Mg and Ag at a volume ratio of 10:1, so as to intersect with the first electrodes. The film thickness referred to here is the value displayed on a quartz crystal oscillator film thickness monitor.

[0276] In this way, an organic EL display device was completed, which had 100 first electrodes, 20 second electrodes, and 200 light-emitting elements where these electrodes intersect. The organic EL display device was then evaluated for adhesion, weather resistance reliability, electrical reliability, and luminescence characteristics. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0277] Example 31 An organic EL display device was produced in the same manner as in Example 30, except that compound (ET-2) was used in place of compound (ET-1) in the n-type charge generating layer, and the adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0278] Example 32 An organic EL display device was produced in the same manner as in Example 30, except that compound (ET-3) was used in place of compound (ET-1) in the n-type charge generating layer, and the adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0279] Example 33 An organic EL display device was produced in the same manner as in Example 30, except that compound (ET-4) was used in place of compound (ET-1) in the n-type charge generation layer, and the adhesion, weather resistance reliability, electrical reliability, and light-emitting characteristics of the organic EL display device were evaluated. The photosensitive resin composition and photomask conditions are shown in Table 9, and the evaluation results are shown in Table 10.

[0280] REFERENCE SIGNS LIST 1 Substrate 2 First electrode 3 Pixel dividing layer 4 Spacer 5 Organic EL layer 6 Second electrode 7 TFT 8 Planarization layer 9 Sealing layer 10 Polarizing layer 11 Ultraviolet absorbing layer 12 Light-transmitting portion 13 Semi-light-transmitting portion 14 Light-shielding portion 15 Cylinder 16 Measurement range for Ra1 17 Measurement range for Ra2 18 Organic EL display device 19 Light-emitting element

Claims

1. An organic EL display device comprising a substrate having a first electrode, a pixel division layer, and a spacer on a base material, and further comprising an organic EL layer and a second electrode, wherein when the maximum value of the surface roughness (Ra1) of the pixel division layer and the surface roughness (Ra2) of the spacer is defined as Ramax, Ramax is 1.0 nm or more and 50 nm or less.

2. The organic electroluminescence display device according to claim 1 , wherein Ra1 is equal to Ramax.

3. 3. The organic electroluminescence display device according to claim 2, wherein an area of ​​an interface between the pixel division layer and the organic electroluminescence layer is 50% or more of an area of ​​an interface between the substrate and the organic electroluminescence layer.

4. The organic electroluminescence display device according to claim 1 , wherein Ra2 is equal to Ramax.

5. 5. The organic electroluminescence display device according to claim 4, wherein an area of ​​an interface between the substrate and the organic electroluminescence layer and an area of ​​an interface between the spacer and the organic electroluminescence layer is 50% or more of an area of ​​an interface between the substrate and the organic electroluminescence layer.

6. 6. The organic electroluminescence display device according to claim 1, wherein an absolute value of the difference between Ra1 and Ra2 is 1.0 nm or more.

7. 7. The organic electroluminescence display device according to claim 1, wherein the pixel dividing layer contains silica particles having a primary particle diameter of 5 to 30 nm.

8. 8. The organic electroluminescence display device according to claim 1, wherein the pixel dividing layer comprises a cured film of a photosensitive resin composition containing an alkali-soluble resin.

9. 9. The organic electroluminescence display device according to claim 8, wherein the alkali-soluble resin contains one or more resins selected from the group consisting of an acrylic resin, a phenolic resin, a polysiloxane resin, a cardo resin, a polyimide resin, a polyimide precursor resin, a polybenzoxazole resin, and a polybenzoxazole precursor resin.

10. The organic electroluminescence display device according to claim 8 , wherein the photosensitive resin composition contains a coloring material.

11. The organic electroluminescence display device according to any one of claims 8 to 10, wherein the photosensitive resin composition contains a liquid repellent material.

12. 12. The organic electroluminescence display device according to claim 1, wherein the organic electroluminescence layer includes an electron transport layer and / or a charge generation layer.

13. The organic electroluminescence display device according to claim 12 , wherein the electron transport layer and / or the charge generation layer contains a donor dopant.

14. 14. The organic electroluminescence display device according to claim 13, wherein the donor dopant contains at least one selected from the group consisting of alkali metals, alkaline earth metals, rare earth metals, inorganic salts of such metals, and complexes of such metals with organic substances.

15. 15. The organic electroluminescence display device according to claim 12, wherein the electron transport layer and / or the charge generation layer contains a compound having a phenanthroline skeleton represented by the following general formula (1): 【Chemistry 1】 (Here, R １ ~R ８ may be the same or different and are selected from a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, a heteroaryl group, and a heterocyclic group. １ , R ３ , R ６ , R ８ At least one of the groups is selected from an adamantyl group, a norbornyl group, a phenylvinyl group, a β-naphthyl group, a phenanthrene group, and a pyrenyl group.

16. 15. The organic electroluminescence display device according to claim 12, wherein the electron transport layer and / or the charge generation layer contains a compound having a phenanthroline skeleton represented by the following general formula (2): 【Chemistry 2】 (Here, R ９ ~R １６ may be the same or different, and each represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, a heteroaryl group, a heterocyclic group, X 1 However, R ９ ~R １６ At least one of is X 1 n is a natural number from 2 to 6. 1 is a single bond or a linking unit that links a plurality of n-valent phenanthroline skeletons derived from benzene, anthracene, pyridine, ethylene, thiophene, furan, methylene, carbazole, cyclohexane, spirobifluorene, triphenylamine, triptycene, or a structure formed by combining these.

17. A method for manufacturing an organic EL display device having a substrate having a first electrode, a pixel division layer, and a spacer on a base material, and further an organic EL layer and a second electrode, the method comprising a step of processing the pixel division layer and the spacer collectively, and a photomask for the collectively processing is a halftone photomask having a light-transmitting portion, a light-shielding portion, and a semi-light-transmitting portion.

18. 18. The method for manufacturing an organic electroluminescence display device according to claim 17, wherein the transmittance of the semi-transparent portion is 15 to 50% of the transmittance of the transparent portion.

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