JP2013137936A - Optical substrate and method for manufacturing the same, and light emitting display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical substrate with which light extraction efficiency can be improved, a method for manufacturing the optical substrate, and a light emitting display device.SOLUTION: An optical substrate includes a translucent substrate 1, a plurality of light scattering walls 2 provided on the translucent substrate 1, a light scattering layer 3 provided on the translucent substrate 1 and covering the light scattering walls 2, and a transparent electrode 5 provided on the light scattering layer 3, and the light scattering layer 3 includes a plurality of light scattering particles 4. The light scattering particles 4 are preferably bubble particles, and the height of each of the light scattering walls 2 is preferably 50% or more and 90% or less of the thickness of the light scattering layer 3. The light scattering particles 4 included in the light scattering layer 3 are preferably formed so as to be generated as bubbles in the light scattering layer 3 comprising a resin cured with one or both of heat and an active energy ray when the resin is coated on the translucent substrate 1 so as to cover the light scattering walls 2 and then cured with the one or both of heat and an active energy ray.

Description

  The present invention relates to an optical substrate capable of improving the light extraction effect, a method for manufacturing the same, and a light-emitting display device including the optical substrate.

  An organic electroluminescence element (hereinafter also referred to as “organic EL element”) applies an electric field to an anode and a cathode to recombine energy between holes injected from the anode and electrons injected from the cathode. The self-luminous element utilizing the principle that the luminescent material emits light in the multilayer structure in which at least the anode, the luminescent layer (including the luminescent material), and the cathode are stacked in that order. Such an organic EL element needs to efficiently extract light emitted from the light emitting layer to the outside.

  However, since the organic EL element is configured by combining materials having different refractive indexes, the light extraction efficiency is affected by the refractive index of such materials. For example, when light from the light emitting layer is emitted from the anode side, the refractive index of the transparent electrode such as ITO is 1.8 to 2.2, and the refractive index of the glass substrate on which the organic EL element is provided is about 1.5. It is. Therefore, the light transmitted through the transparent electrode is easily totally reflected by the glass substrate having a refractive index smaller than that of the transparent electrode, and the light extraction efficiency is lowered.

  In order to solve such a problem, Patent Document 1 improves the light extraction efficiency by providing a diffraction grating having a concavo-convex structure between an anode or a cathode and a glass substrate. In Patent Document 2, for the purpose of improving the difficulty of manufacturing the diffraction grating shown in Patent Document 1 and the instability of product characteristics, an etching solution is applied to the glass substrate surface on the side in contact with the anode to provide grooves. A light diffraction efficiency is improved by providing a diffraction grating formed by filling the groove with a dispersion of fine particles. In Patent Document 3, a light scattering layer having pores in the size range of 30 nm to 50 nm is provided between the anode and the glass substrate to improve light extraction efficiency.

Japanese Patent Laid-Open No. 11-283951 JP 2004-335301 A JP 2005-63704 A

  However, as described above, the technique described in Patent Document 1 has a problem of difficulty in manufacturing a diffraction grating and instability of product characteristics, and is not a practical solution. In addition, the technique described in Patent Document 2 has a problem in that it is still unstable and difficult to use since the groove is formed with an etching solution. In addition, although the techniques described in these Patent Documents 1 and 2 can change the traveling direction of light by a diffraction grating, the light traveling in the glass substrate is reflected at the interface with the air and horizontally in the glass substrate. As a result, the light extraction efficiency could not be sufficiently improved.

  Further, although the technique described in Patent Document 3 can improve the light extraction efficiency to some extent by an easy manufacturing method, the light scattered in the light scattering layer is reflected at the interface with the glass substrate, and further the glass substrate and air The light was also reflected at the interface with the light and guided in the horizontal direction in the glass substrate, and the light extraction efficiency could not be sufficiently improved.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical substrate capable of improving the light extraction efficiency and a method for manufacturing the same. Another object of the present invention is to provide a light emitting display device such as an organic EL element having such an optical substrate.

  (1) An optical substrate according to the present invention for solving the above problems is provided on a light-transmitting substrate, a plurality of light scattering walls provided on the light-transmitting substrate, and the light-transmitting substrate. And a light scattering layer covering the light scattering wall, and a transparent electrode provided on the light scattering layer, wherein the light scattering layer has a plurality of light scattering particles.

  According to this invention, since the light scattering wall and the light scattering layer are provided between the translucent substrate and the transparent electrode, when the light enters from the transparent electrode side, the light is the light that the light scattering layer has. The light is refracted or reflected by the scattering particles, and part of the light is extracted from the light-transmitting substrate. Further, another part of the light refracted or reflected by the light scattering particles travels in the light scattering layer, and is refracted or reflected again by the light scattering particles included in the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering wall travels in the light scattering layer, and is refracted or reflected again by the light scattering particles of the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. By repeating such refraction or reflection, light incident from the transparent electrode side is efficiently extracted from the translucent substrate.

  The optical substrate according to the present invention is configured such that the light scattering particles are bubble particles.

  According to this invention, since the light scattering particle is a bubble particle, the refractive index of the bubble particle is about 1.0, and the light is refracted or reflected on the surface of the bubble particle to effectively scatter the light. Can do.

  The optical substrate according to the present invention is configured such that the height of the light scattering wall is not less than 50% and not more than 90% of the thickness of the light scattering layer.

  According to this invention, since the height of the light scattering wall is not less than 50% and not more than 90% of the thickness of the light scattering layer, the opportunity for light refracted or reflected by the light diffusing particles of the light scattering layer to hit the light diffusion wall. Increase. As a result, the light hitting the light scattering wall is refracted or reflected by the light diffusing wall, and a part of the light is taken out from the translucent substrate.

  In the optical substrate according to the present invention, the refractive index of the light scattering wall is configured to be smaller than the refractive index of the light scattering layer.

  According to this invention, since the refractive index of the light scattering wall is smaller than the refractive index of the light scattering layer, the light refracted or reflected by the light diffusion particles of the light scattering layer hits the light diffusion wall and is refracted or reflected. As a result, a part of the light is extracted from the translucent substrate.

  The optical substrate according to the present invention is configured such that the refractive index in the light scattering particles is smaller than the refractive index of the light scattering layer other than the light scattering particles.

  According to this invention, since the refractive index in the light scattering particle is smaller than the refractive index of the light scattering layer other than the light scattering particle, the light traveling in the light scattering layer is refracted or reflected by the light diffusion particle and scattered. . As a result, a part of the light is extracted from the translucent substrate.

  (2) A method for manufacturing an optical substrate according to the present invention for solving the above-described problems includes a step of forming a plurality of light scattering walls on a light transmitting substrate, and the light scattering wall on the light transmitting substrate. And a step of forming a light scattering layer having a plurality of light scattering particles so as to cover the surface, and a step of forming a transparent electrode on the light scattering layer.

  According to the present invention, the light scattering layer having a plurality of light scattering particles is formed on the light transmitting substrate so as to cover the light scattering wall, and then the transparent electrode is formed on the light scattering layer. When light enters the optical substrate from the transparent electrode side, the light is refracted or reflected by the light scattering particles of the light scattering layer, and a part of the light is extracted from the translucent substrate to the outside. Further, another part of the light refracted or reflected by the light scattering particles travels in the light scattering layer, and is refracted or reflected again by the light scattering particles included in the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering wall travels in the light scattering layer, and is refracted or reflected again by the light scattering particles of the light scattering layer, and a part of the light is emitted from the translucent substrate. Take out to the outside. By repeating such refraction or reflection on the light scattering particles and the light scattering wall, the light incident from the transparent electrode side is efficiently extracted from the translucent substrate.

  In the method for producing an optical substrate according to the present invention, the light diffusing particles of the light scattering layer are cured on one or both of heat and active energy rays so as to cover the light scattering wall on the light transmissive substrate. After the resin to be applied is applied, it is configured to be generated as bubbles in the light scattering layer made of the resin when cured with one or both of the heat and active energy rays.

  According to this invention, after applying the resin that cures the light diffusing particles with one or both of heat and active energy rays so as to cover the translucent substrate provided with the light scattering wall, the heat and active energy rays are applied. When one or both of these are cured, bubbles are generated in the light scattering layer made of the resin, so that a light scattering layer having light scattering particles can be formed by simple means such as heating or ultraviolet irradiation.

  In the method of manufacturing an optical substrate according to the present invention, the light scattering wall is patterned after applying a translucent resin so as to have a height of 50% to 90% of the thickness of the light scattering layer. Configure.

  According to the present invention, the light scattering wall is patterned after applying the translucent resin, and is formed at a height of 50% to 90% of the thickness of the light scattering layer. A wall can be formed. In addition, since the height of the light scattering wall is set to 50% or more and 90% or less of the thickness of the light scattering layer, the chance that the light refracted or reflected by the light diffusion particles of the light scattering layer hits the light diffusion wall may be increased. In addition, the light hitting the light scattering wall can be refracted or reflected by the light diffusion wall, and a part of the light can be taken out from the translucent substrate.

  (3) A light-emitting display device according to the present invention for solving the above-described problems is provided with a light-transmitting substrate, a plurality of light scattering walls provided on the light-transmitting substrate, and the light-transmitting substrate. And a light scattering layer that covers the light scattering wall and has a plurality of light scattering particles, and a light emitter provided on the light scattering layer.

  According to the present invention, since the light-scattering layer is provided on the light-scattering layer, when light emitted from the light-emitting body enters the light-scattering layer, the light is refracted or reflected by the light-scattering particles of the light-scattering layer, and the light Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering particles travels in the light scattering layer, and is refracted or reflected again by the light scattering particles included in the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering wall travels in the light scattering layer, and is refracted or reflected again by the light scattering particles of the light scattering layer, and a part of the light is emitted from the translucent substrate. Take out to the outside. Such refraction or reflection is repeated between the light scattering particles and the light scattering wall, whereby the light incident from the light emitter is efficiently extracted from the light transmitting substrate.

  In the light emitting display device according to the present invention, the light emitter is formed on a transparent first electrode provided on the light scattering layer, an organic EL layer provided on the first electrode, and the organic EL layer. And a second electrode provided.

  According to this invention, the luminous body includes a transparent first electrode provided on the light scattering layer, an organic EL layer provided on the first electrode, and a second provided on the organic EL layer. Since it has an electrode, the light emitted from the organic EL layer is efficiently extracted from the translucent substrate, as in the above-described operation.

  (4) An optical substrate according to another aspect of the present invention for solving the above-described problems includes a light-transmitting substrate, a plurality of light scattering walls provided on the light-transmitting substrate, and the light-transmitting substrate. A light scattering layer having a plurality of light scattering particles provided on and covering the light scattering wall, wherein the height of the light scattering wall is not less than 50% and not more than 90% of the thickness of the light scattering layer It is characterized by being.

  According to this invention, since the light scattering wall and the light scattering layer are provided on the translucent substrate, when light enters from the light scattering layer side, the light is refracted by the light scattering particles of the light scattering layer. Alternatively, the light is reflected and part of the light is extracted from the light-transmitting substrate. Further, another part of the light refracted or reflected by the light scattering particles travels in the light scattering layer, and is refracted or reflected again by the light scattering particles included in the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering wall travels in the light scattering layer, and is refracted or reflected again by the light scattering particles of the light scattering layer, and a part of the light is emitted from the translucent substrate. Take out to the outside. Such refraction or reflection is repeated between the light scattering particles and the light scattering wall, whereby the light incident from the light scattering layer side is efficiently extracted from the translucent substrate.

  According to the optical substrate of the present invention, when light is incident on the light scattering layer, the light is refracted or reflected by the light scattering particles of the light scattering layer, and a part of the light is transmitted from the translucent substrate to the outside. It is taken out. Further, another part of the light refracted or reflected by the light scattering particles travels in the light scattering layer, and is refracted or reflected again by the light scattering particles included in the light scattering layer, or refracted or reflected by the light scattering wall, Part of the light is extracted from the translucent substrate. Further, another part of the light refracted or reflected by the light scattering wall travels in the light scattering layer, and is refracted or reflected again by the light scattering particles of the light scattering layer, and a part of the light is emitted from the translucent substrate. Take out to the outside. Such refraction or reflection is repeated between the light scattering particles and the light scattering wall, whereby the light incident on the light scattering layer is efficiently extracted from the light transmitting substrate.

  According to the method for manufacturing an optical substrate according to the present invention, an optical substrate having the above effects can be manufactured by an extremely easy means.

  According to the light emitting display device of the present invention, as described above, since the optical substrate having a high light extraction efficiency is provided, the light generated in the light emitting layer can be extracted efficiently.

It is a typical sectional view showing an example of an optical substrate concerning the present invention. It is typical sectional drawing which shows another example of the optical board | substrate which concerns on this invention. It is explanatory drawing which shows the aspect in which light is refracted or reflected by a light-scattering particle and a light-scattering wall. It is explanatory drawing which shows the aspect in which light is refracted or reflected with a light-scattering particle. It is typical sectional drawing which shows an example of the light emission display apparatus which concerns on this invention. It is typical sectional drawing which shows another example of the light emission display apparatus which concerns on this invention.

  An optical substrate, a manufacturing method thereof, and a light-emitting display device according to the present invention will be described in detail with reference to the drawings. The present invention can be modified in various ways as long as it has the technical features, and is not limited to the embodiments specifically shown below.

[Optical element and manufacturing method thereof]
As shown in FIGS. 1 and 2, the optical substrate 10 according to the present invention includes a translucent substrate 1, a plurality of light scattering walls 2 provided on the translucent substrate 1, and the translucent substrate 1. A light scattering layer 3 covering the light scattering wall 2 and a transparent electrode 5 provided on the light scattering layer 3, and the light scattering layer 3 has a plurality of light scattering particles 4. There is a feature.

  Hereinafter, each configuration will be described in detail.

(Translucent substrate)
The translucent substrate 1 functions as a base material for the light scattering wall 2 and the light scattering layer 3 described later, and also functions to transmit most of the light refracted or reflected by the light scattering wall 2 or the light scattering layer 3. To do. The light-transmitting substrate 1 may be a light-transmitting substrate made of a material such as glass, quartz, or resin. In particular, a substrate having a transmittance of 85% or more as a single substrate is preferably used. In addition, the transmittance | permeability here is the value measured, for example with the light transmittance meter (model: HM-150) by Murakami Color Research Laboratory Co., Ltd. etc. Although the thickness of the translucent board | substrate 1 is not specifically limited, Usually, it exists in the range of 30 micrometers-500 micrometers.

  Examples of the glass substrate include substrates made of alkali-free glass, soda glass, lead alkali glass, borosilicate glass, aluminosilicate glass, silica glass, and the like. Examples of the resin substrate include polyester resins such as polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, acrylic resins such as polymethacrylate, polymethyl acrylate, and polymethyl methacrylate, polycarbonate resins, polystyrene resins, poly A resin obtained by curing an ionizing radiation curable resin composed of a thermoplastic resin such as methylpentene resin, an oligomer such as polyester acrylate, urethane acrylate, epoxy acrylate, and / or an acrylate monomer with electromagnetic radiation such as ultraviolet rays or electron beams, And the like.

  As the translucent substrate 1, a flexible material, a hard material, or the like is selected according to the application. These translucent substrates 1 may be substrates having gas barrier properties that block gas such as moisture and oxygen as necessary.

(Light scattering wall)
As shown in FIGS. 1 and 2, a plurality of light scattering walls 2 are provided on the light-transmitting substrate 1. Although the material of the light-scattering wall 2 is not specifically limited, For example, the transparent resin material whose refractive index n3 is smaller than the refractive index n2 of the light-scattering layer 2 mentioned later is used preferably. Such a material cannot be generally described in relation to the type of the light scattering layer 2, but can be selected from, for example, commercially available photosensitive resin materials. By forming the light scattering wall 2 with a material having a refractive index n3 smaller than the refractive index n2 of the light scattering layer 3, the light refracted or reflected by the light diffusing particles 4 of the light scattering layer 3 hits the light diffusion wall 2 and is refracted. Or it reflects. As a result, a part of the light is easily extracted from the translucent substrate 1 to the outside.

  The height H of the light scattering wall 2 is not particularly limited, but is preferably 50% or more and 90% or less of the thickness T of the light scattering layer 3. By setting the height H of the light scattering wall 2 within this range, the opportunity for the light refracted or reflected by the light diffusing particles 4 of the light scattering layer 3 to hit the light diffusing wall 2 increases. As a result, the light striking the light scattering wall 2 is refracted or reflected by the light diffusion wall 2, and a part of the light is extracted from the translucent substrate 1 to the outside. The height H of the light scattering wall 2 is usually 0.4 μm or more and 2 μm or less.

  The light scattering wall 2 is formed in a predetermined pattern by, for example, applying a photosensitive resin material with a predetermined thickness on the translucent substrate 1 and exposing and developing the photosensitive resin material. The pattern of the light scattering wall 2 can have a width of 5 μm or more and 30 μm or less, for example. Moreover, as the planar view shape of the light-scattering wall 2, patterns can be formed in various shapes such as a linear shape, a lattice shape, and a curved shape. In addition, the pitch of the light scattering walls 2 is not particularly limited, but may be, for example, 20 μm or more and 200 μm or less.

(Light scattering layer)
As shown in FIGS. 1 and 2, the light scattering layer 3 is provided on the translucent substrate 1 and covers the light scattering wall 2. Furthermore, the light scattering layer 3 has a plurality of light scattering particles 4. “Cover” means that the light scattering layer 3 is provided on the translucent substrate 1 to be thicker than the light scattering wall 2 to cover the light scattering wall 2 as shown in FIGS. 1 and 2. .

  Such a light scattering layer 3 is formed by applying a resin that is cured by one or both of heat and active energy rays and then curing the resin by one or both of the heat and active energy rays. At one or both of heat and active energy rays at this time, bubbles are generated in the light scattering layer 3 made of the applied resin, and the bubbles become light scattering particles 4. Thus, after applying the resin which hardens | cures with one or both of a heat | fever and an active energy ray so that the light-diffusion grain 4 may cover the translucent board | substrate 1 with which the light-scattering wall 2 was provided, the heat | fever and active energy are applied. It is a bubble particle produced as a bubble in the light scattering layer 3 made of the resin when cured with one or both of the lines. The refractive index of the bubble particle is about 1.0, and light is refracted or reflected on the surface of the bubble particle, and the light can be effectively scattered.

  Examples of the resin for forming the light diffusion layer 2 include thermosetting resins and active energy ray curable resins such as ultraviolet curable resins. Examples of the thermosetting resin include isonate-based and epoxy-based thermosetting resins. Examples of the active energy ray-curable resin include an active energy ray-curable resin having an acrylate-based or methacrylate-based reactive vinyl group. In particular, if the resin contains a volatile component that volatilizes at a predetermined temperature, the volatile component is vaporized by heating and bubbles are formed. A light scattering layer 3 having certain light scattering particles 4 can be formed. Examples of such volatile components include pegmia, methyl ethyl ketone, and ethyl sulfate. The vaporization temperature of the volatile component contained in the resin is unique to the volatile component and varies depending on the volatile component contained.

  In the case of a thermosetting resin, bubbles are formed in the thermosetting resin by adjusting the temperature when the thermosetting resin is cured by applying heat to the coated thermosetting resin, and the bubbles are cured in a state where the bubbles are generated. Light scattering particles 4 that are particles are formed. Specifically, when curing is performed by applying heat to the thermosetting resin after coating, general preheating (preliminary firing) and main heating (main firing) are not performed stepwise, but preheating ( By performing the main heating (pre-firing) without performing pre-firing, the volatile components in the thermosetting resin are vaporized to generate bubbles, and the bubbles are cured in a state where the bubbles are generated. The scattering particles 4 are formed.

  In the case of an ultraviolet curable resin, the applied ultraviolet curable resin is heated to generate bubbles in the resin, and in the state where the bubbles are generated, the ultraviolet light is irradiated and cured to form light scattering particles 4 which are bubble particles. Form. Thus, in the case of an ultraviolet curable resin, it is preferable to generate the light scattering particles 4 which are bubble particles by a combined effect of both heat and ultraviolet rays.

  The resin for forming the light scattering layer 3 is formed by applying the resin on the translucent substrate 1 on which the light scattering wall 2 is formed by various coating methods such as a spin coating method and curing the resin.

  The active energy ray is an ultraviolet ray, an electron beam or the like, and since an ultraviolet curable resin is usually used, the ultraviolet ray is preferably applied. Thus, the light scattering layer 3 having the light scattering particles 4 can be easily formed by simple means such as heating and ultraviolet irradiation.

(Refraction or reflection in the light scattering layer)
3 and 4 are explanatory diagrams of light refraction or reflection in the light scattering layer 3. Light incident on the light scattering layer 3 from the first electrode 5 side is refracted or reflected by the light scattering particles 3 in the light scattering layer 3, and part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering particle 4 further proceeds in the light scattering layer 3 and is refracted or reflected again by the light scattering particle 4 included in the light scattering layer 3, or the light scattering wall 2 And part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering wall 2 further proceeds in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3, and a part of the light is The light-transmitting substrate 1 is taken out to the outside. Such refraction or reflection is repeated at the light scattering particle 4 and the light scattering wall 2, whereby the light incident on the light scattering layer 3 from the transparent electrode 5 side is efficiently extracted from the translucent substrate 1. .

  At this time, by specifying the refractive index of each layer, the above-described light extraction efficiency can be further improved, and the directivity of light traveling in the normal direction of the translucent substrate 1 can be further increased. . The normal direction is a direction orthogonal to the substrate surface of the translucent substrate 1.

  Specifically, the refractive index n1 in the light scattering particle 4 in the light scattering layer 3, the refractive index n2 of the light scattering layer 3 other than the light scattering particle 4, and the refractive index n3 of the light scattering wall 2 are Are also preferably different. In particular, the refractive index n1 in the light scattering particle 4 is preferably smaller than the refractive index n2 of the light scattering layer 3 other than the light scattering particle 4. By doing so, the light traveling in the light scattering layer 3 is refracted or reflected by the light diffusing particles 4 and scattered, so that a part of the light is effectively extracted from the translucent substrate 1 to the outside. . Furthermore, the refractive index n3 of the light scattering wall 2 is also preferably smaller than the refractive index n2 of the light scattering layer 3 other than the light scattering particles 4. By doing so, the light traveling in the light scattering layer 3 is scattered by being refracted or reflected by the light scattering wall 2 as described above, and a part of the light is effectively extracted from the translucent substrate 1 to the outside. It will be.

  The refractive index of the transparent electrode 5 such as ITO is in the range of about 1.8 to 2.2, and the refractive index of the glass substrate which is the translucent substrate 1 is about 1.5. Therefore, in the conventional configuration that does not have the light scattering wall 2 and the light scattering layer 3 constituting the present invention, the light transmitted through the transparent electrode 5 is easily totally reflected by the glass substrate having a refractive index smaller than that of the transparent electrode 5. The light extraction efficiency has declined. However, in the optical substrate 10 according to the present invention having the light scattering wall 2 and the light scattering layer 3, the light that has passed through the transparent electrode 5 is refracted or reflected by the light scattering particles 4 in the light scattering layer 3, and the light is further reflected. It can be refracted or reflected by the light scattering wall 2 so that more light is directed toward the translucent substrate 1, and the light extraction surface can have directivity. As a result, light can be collected on the light transmissive substrate 1 side which is the light extraction surface, and the light extraction efficiency per unit area can be improved.

(Transparent electrode)
The transparent electrode 5 has an arbitrary configuration, and is provided on the light scattering layer 3 in the optical substrate 10A shown in FIG. 1, but is not provided in the optical substrate 10B shown in FIG. The transparent electrode 5 becomes the first electrode 5 in the light emitting display device 11 described later, and functions as an electrode for injecting charges into the organic EL layer 6. The transparent electrode 5 is made of a transparent conductive oxide such as In—Sn—O (ITO), In—Zn—O (IZO), Zn—O, Zn—O—Al, or Zn—Sn—O. In particular, it is preferably formed of a transparent conductive oxide of ITO or IZO. The transparent electrode 5 made of ITO or IZO is excellent in electrical conductivity and light transmittance, and has low electrical resistivity. Therefore, the transparent electrode 5 is used as the first electrode 5 of the light emitting display device 11 to be described later while improving the light extraction efficiency. In this case, the driving voltage of the light emitting layer 6B can be lowered.

  The transmittance of the transparent electrode 5 formed of a transparent conductive oxide is preferably 80% or more so that the light transmittance in the visible region 380 nm to 780 nm is 50% or more. This transmittance is also a value measured by, for example, a light transmittance meter (model: HM-150) manufactured by Murakami Color Research Laboratory. The thickness of the transparent electrode 5 is arbitrarily set within a range satisfying the above-described transmittance, and is usually within a range of 0.1 μm to 0.15 μm.

  The transparent electrode 5 is formed by a film forming unit and a patterning unit according to the type of the transparent conductive oxide and the heat resistance of the translucent substrate 1. For example, a vacuum deposition method, a sputtering method, various CVD methods, and the like can be applied as the film forming unit, and photolithography can be applied as the patterning unit.

(Production method)
The optical substrate 10 includes a step of forming a plurality of light scattering walls 2 on the light transmissive substrate 1 and a light scattering layer having a plurality of light scattering particles 4 on the light transmissive substrate 1 so as to cover the light scattering walls 2. 3 and a process of forming the transparent electrode 5 on the light scattering layer 3. Since the method for forming the light scattering wall 2, the light scattering layer 3, and the transparent electrode 5 in each step has been described in the description section of each configuration described above, the description thereof is omitted here, but the optical substrate according to the present invention. According to this manufacturing method, the optical substrate 10 having the above-described special effects can be easily manufactured in a mode in which characteristics are stable.

  As described above, according to the optical substrate and the manufacturing method thereof according to the present invention, since the light scattering wall 2 and the light scattering layer 3 are provided, light enters from the transparent electrode 5 side or the light scattering layer 3 side. Then, the light is refracted or reflected by the light scattering particles 4 of the light scattering layer 3, and a part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering particles 4 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3 or is reflected by the light scattering wall 2. The light is refracted or reflected, and a part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering wall 2 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3, and part of the light is transmitted. It is taken out from the optical substrate 1 to the outside. Such refraction or reflection is repeated at the light scattering wall 2 or the light scattering layer 3, whereby the incident light is efficiently extracted from the translucent substrate 1.

  The optical substrate 10A provided with the transparent electrode 5 is preferably used for various display devices and the like as long as it is used for improving the light extraction efficiency. For example, it is preferably used as a constituent member of a light emitting display device 11, a color filter, a liquid crystal display element, electronic paper or the like, which will be described later. Specifically, the transparent electrode 5 is used as an anode or a cathode provided in the light emitting display device 11, used as a liquid crystal drive electrode provided in a liquid crystal display element or a color filter, or an electronic paper monochrome inversion drive electrode. Used as Other than this, for example, if the transparent electrode 5 has an electromagnetic wave shielding function, it may be used for the display surface of the plasma display panel.

  On the other hand, the optical substrate 10B on which the transparent electrode 5 is not provided does not require an electrode, but is used by being attached to the display surface of various display devices as long as it is used for improving the light extraction efficiency. For example, it can be attached to a display surface of a display device such as an organic EL display, a liquid crystal display, electronic paper, a mobile phone, a smart phone, or a tablet. By doing so, the directivity of the light emitted from the display surface toward the viewer can be enhanced.

[Light-emitting display device]
(Basic configuration)
The light emitting display device 11 according to the present invention includes a light transmissive substrate 1, a plurality of light scattering walls 2 provided on the light transmissive substrate 1, and a light scattering wall 2 provided on the light transmissive substrate 1. A light scattering layer 3 that covers and has a plurality of light scattering particles 4 and a light emitter (5, 6, 7) provided on the light scattering layer 3 are provided. In the light emitting display device 11, when light emitted from the light emitter is incident on the light scattering layer 3 side, the light is refracted or reflected by the light scattering particles 4 included in the light scattering layer 3, and a part of the light is transmitted. It is taken out from the optical substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering particles 4 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3 or is reflected by the light scattering wall 2. The light is refracted or reflected, and a part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering wall 2 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3, and part of the light is transmitted. It is taken out from the optical substrate 1 to the outside. Such refraction or reflection is repeated at the light scattering particles 4 and the light scattering wall 2, whereby light incident from the light emitter is efficiently extracted from the translucent substrate 1.

  The illuminant is not particularly limited as long as it has a luminescence source, for example, an organic EL element having a self-luminous luminescent layer, a liquid crystal display element or electronic paper having a backlight, or a plasma display panel. Etc.

  Specifically, as shown in FIGS. 5 and 6, a transparent first electrode 5 provided on the light scattering layer 2, an organic EL layer 6 provided on the first electrode 5, and an organic EL layer A light emitter made of an organic EL element having the second electrode 7 provided on the substrate 6 can be exemplified. In detail, the light emitting display device 11 including such an organic EL element is provided on the translucent substrate 1, the plurality of light scattering walls 2 provided on the translucent substrate 1, and the translucent substrate 1. A light scattering layer 3 that covers the light scattering wall 2 and has a plurality of light scattering particles 4, a transparent first electrode 5 provided on the light scattering layer 3, and an organic EL layer provided on the first electrode 5 6 and a second electrode 7 provided on the organic EL layer 6.

  Below, although each structure of the light emission display apparatus 11 provided with the organic EL element is demonstrated, among each structure, the translucent board | substrate 1, the light-scattering wall 2, the light-scattering layer 3, and the transparent 1st electrode 5 (above-mentioned) In the above description, “transparent electrode 5”) is as described above, and the description thereof is omitted or minimized here.

(First electrode)
The first electrode 5 is the same as the transparent electrode 5 described above. However, when applied to the light emitting display device 11, the first electrode 5 is an electrode for supplying holes or electrons to the organic EL layer 6 formed thereafter. is there. The first electrode 5 is provided on the light extraction side of the light generated in the organic EL layer 6. Usually, from the viewpoint of the manufacturing procedure, it is preferable to use the first electrode 5 as an anode and the second electrode 7 described later as a cathode.

(Organic EL layer)
As shown in FIG. 5, the organic EL layer 6 is sandwiched between the first electrode 5 and the second electrode 7, and has at least a hole injection transport layer 6A and a light emitting layer 6B. Is configured to have a hole injecting and transporting layer 6A, a light emitting layer 6B, and an electron injecting and transporting layer 6C. As long as this organic EL layer 6 has a layer having a hole injecting and transporting function, a light emitting layer, and a layer having an electron injecting and transporting function, layers having various names may be provided. For example, a hole injection layer, a hole transport layer, a hole injection transport layer, an electron transport layer, an electron injection layer, an electron injection transport layer, and the like are provided as necessary. 6, the hole injection layer 6a, the hole transport layer 6b, the light emitting layer 6c, the electron transport layer 6d, and the electron injection layer 6e may be provided in this order from the first electrode 5 side. .

  In general, a hole injection / transport layer provided with a hole transport function is often used in the hole injection layer, and an electron injection / transport layer provided with an electron transport function is used in the electron injection layer. Since there are many cases, in the following, as a representative configuration, as shown in FIG. 5, the first electrode 5 is an anode, and from the anode side, a hole injection transport layer 6A, a light emitting layer 6B, an electron injection transport layer 6C. The organic EL layer 6 composed of the above will be specifically described as an example. Also, if necessary, as in a hole blocking layer or an electron blocking layer, it prevents holes or electrons from penetrating, further prevents exciton diffusion, and confines excitons in the light emitting layer for recombination. A layer or the like for increasing efficiency may be added.

(Hole injection transport layer)
The hole injection transport layer 6A is provided in contact with the first electrode 5 and functions to stabilize the injection of holes into the light emitting layer 6B and to increase the light emission efficiency. Since the hole injection transport layer 6A is provided between the first electrode 5 and the light emitting layer 6B, the hole injection transport layer 6A may be any layer that acts to transport holes injected from the first electrode 5 into the light emitting layer 6B. There is no particular limitation. The hole injection transport layer 6A may be a single layer called a hole injection layer or a single layer called a hole transport layer as long as it has a hole injection function and a hole transport function, Further, it may have a two-layer structure including a layer called a hole injection layer and a layer called a hole transport layer, and when the light emitting layer 6B has both a hole injection function and a hole transport function. May not be provided as a hole injecting and transporting layer.

  The constituent material of the hole injecting and transporting layer 6A is not particularly limited as long as it is a material that can stably transport holes injected from the first electrode 5 into the light emitting layer 6B. In addition to the compounds exemplified as the light-emitting material of the layer 6B (pigment-based light-emitting material, metal complex-based light-emitting material, polymer-based light-emitting material), arylamines, starburst amines, phthalocyanines, vanadium oxide, molybdenum oxide, oxidation Oxides such as ruthenium and aluminum oxide, conductive polymers such as amorphous carbon, polyaniline, polythiophene, and polyphenylene vinylene, and derivatives thereof can be used. Conductive polymers such as polyaniline, polythiophene, and polyphenylene vinylene and derivatives thereof may be doped with an acid. Specifically, N, N′-bis (naphthalen-1-yl) -N, N′-bis (phenyl) -benzidine (α-NPD), 4,4,4-tris (3-methylphenylphenylamino) ) Triphenylamine (MTDATA), poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (PEDOT / PSS), polyvinylcarbazole (PVCz), and the like.

  As a film formation method of the hole injection transport layer 6A, for example, a dry method such as a vacuum deposition method or a sputtering method, or a printing method, an ink jet method, a spin coating method, a casting method, a dip coating method, a bar coating method, a blade Examples thereof include wet methods such as a coating method, a roll coating method, a gravure coating method, a flexographic printing method, and a spray coating method. The thickness of the hole injecting and transporting layer 6A is particularly limited as long as holes are sufficiently injected from the first electrode 5 serving as the anode and sufficiently exhibit the function of transporting holes to the light emitting layer 6B. Although not specifically, it can be set in the range of about 0.5 nm to 1000 nm, and it is preferably in the range of 5 nm to 500 nm.

(Light emitting layer)
The light emitting layer 6B has a function of emitting light by providing a recombination field between electrons and holes. For example, as shown in FIG. 5, a hole injecting and transporting layer 6A and an electron injecting and transporting layer 6C are provided. It is sandwiched between them. Examples of the constituent material of the light emitting layer 6B include a dye-based light-emitting material, a metal complex-based light-emitting material, and a polymer-based light-emitting material.

  Examples of dye-based light-emitting materials include cyclopentadiene derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, Examples thereof include pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, coumarin derivatives, oxadiazole dimers, and pyrazoline dimers.

  The metal complex light emitting material has Al, Zn, Be, Ir, Pt, etc. as the central metal, or rare earth metals such as Tb, Eu, Dy, etc., and oxadiazole, thiadiazole, phenylpyridine, phenyl as the ligand A metal complex having a benzimidazole, quinoline structure, or the like can be given. Examples of such metal complexes include aluminum quinolinol complexes, benzoquinolinol beryllium complexes, benzoxazole zinc complexes, benzothiazole zinc complexes, azomethyl zinc complexes, porphyrin zinc complexes, europium complexes, iridium metal complexes, platinum metal complexes, and the like. Specifically, tris (8-hydroxyquinolinolato) aluminum complex (Alq3) can be used.

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

  The thickness of the light emitting layer 6B is not particularly limited as long as it is a thickness that can provide a function of emitting light by providing a recombination field between electrons and holes, and is about 1 nm to 200 nm. It can be. The method for forming the light emitting layer 6B is not particularly limited as long as it is a method capable of forming a fine pattern required for the light emitting display device 11. For example, vapor deposition method, printing method, ink jet method, spin coating method, casting method, dipping method, bar coating method, blade coating method, roll coating method, gravure coating method, flexographic printing method, spray coating method, self-organization method ( An alternating adsorption method, a self-assembled monolayer method) and the like. Of these, vapor deposition, spin coating, and ink jet are preferred.

(Electron injection transport layer)
Since the electron injecting and transporting layer 6C is provided between the light emitting layer 6B and the second electrode 7, the electron injecting and transporting layer 6C may be any layer that acts to stably transport the electrons injected from the second electrode 7 to the light emitting layer 6B. There is no particular limitation. The electron injection / transport layer 6C may be a single layer called an electron injection layer or a single layer called an electron transport layer as long as it has an electron injection function and an electron transport function. It may be a two-layer structure composed of a layer called an electron transport layer and a layer called an electron transport layer, and when the light emitting layer 6B has both an electron injection function and an electron transport function, it is provided as an electron injection transport layer. It does not have to be.

  The constituent material having an electron injection function is not particularly limited as long as it can stabilize the injection of electrons into the light emitting layer 6B. The light emitting material (the dye-based light emitting material) of the light emitting layer 6B is not particularly limited. In addition to compounds exemplified as metal complex-based light-emitting materials and polymer-based light-emitting materials), simple substances of alkali metals or alkaline earth metals such as Ba, Ca, Li, Cs, Mg, and Sr, magnesium fluoride, and calcium fluoride Alkali metal or alkaline earth metal fluorides such as strontium fluoride, barium fluoride, lithium fluoride, cesium fluoride, alkali metal alloys such as aluminum lithium alloy, metals such as magnesium oxide, strontium oxide, aluminum oxide Organics of alkali metals such as oxides and sodium polymethyl methacrylate polystyrene sulfonate Mention may be made of the body or the like.

  The constituent material having an electron transport function is not particularly limited as long as it is a material that can transport electrons injected from the second electrode 7 into the light emitting layer 6B. For example, bathocuproin (BCP) And phenanthroline derivatives such as bathophenanthroline (Bpehn), triazole derivatives, oxadiazole derivatives, and aluminum quinolinol complexes such as tris (8-hydroxyquinolinolato) aluminum (Alq3).

  As a method for forming the electron injecting and transporting layer 6C, for example, a dry method such as a vacuum deposition method or a sputtering method, or a printing method, an ink jet method, a spin coating method, a casting method, a dip coating method, a bar coating method, or a blade coating method. Examples thereof include a wet method such as a method, a roll coating method, a gravure coating method, a flexographic printing method, and a spray coating method. The thickness of the electron injecting and transporting layer 6C is not particularly limited as long as the electron injecting function and the electron transporting function are sufficiently exhibited, and is preferably in the range of 0.1 nm to 300 nm. More preferably, it is in the range of 0.5 nm to 200 nm.

(Second electrode)
The second electrode 7 is an electrode for supplying electrons to the light emitting layer 6B. Since the second electrode 7 is not on the light extraction side, the constituent material is not particularly limited, and examples thereof include titanium, gold, chromium, iron, molybdenum, tungsten, copper, ruthenium, rhenium, ITO, and IZO. . Although the thickness of the 2nd electrode 7 is not specifically limited, Usually, it is preferable that it is the range of 150 nm-300 nm.

  Examples of the method for forming the second electrode 7 include physical vapor deposition methods such as chemical vapor deposition, vacuum deposition, sputtering, and ion plating. A sputtering method or an ion plating method which is a high energy film forming means capable of forming a simple film is preferable.

(Other configurations)
After the second electrode 7 is formed, for example, a sealing layer (not shown) may be provided, or a transparent base material (not shown) may be provided via the sealing layer as necessary. The sealing layer may be formed by applying a polymer material, or may be a laminate of resin films made of a polymer material. Examples of the polymer material include fluorine resin, polyethylene, polypropylene, polyvinyl chloride, polyvinyl fluoride, polystyrene, ABS resin, polyamide, polyacetal, polyester, polycarbonate, modified polyphenylene ether, polysulfone, polyarylate, polyetherimide, Polyethersulfone, Polyamideimide, Polyimide, Polyphenylene sulfide, Liquid crystalline polyester, Polyethylene terephthalate, Polybutylene terephthalate, Polyethylene naphthalate, Polymicroxylene dimethylene terephthalate, Polyoxymethylene, Polyethersulfone, Polyetheretherketone, Poly Acrylate, acrylonitrile-styrene resin, phenol resin, urea resin, melamine resin, unsaturated polymer Ester resins, epoxy resins, acrylic resins, polyurethane, silicone resin, amorphous polyolefins, and the like. Two or more types of copolymers can also be used. An organic-inorganic material that can be formed by a sol-gel reaction can also be used.

A barrier layer (not shown) may be formed. Examples of the barrier layer include various inorganic layers and organic layers having a barrier function. For example, an inorganic layer made of a nitride or oxide such as Si ₃ N ₄ , SiO ₂ , or Al ₂ O ₃ can be formed by physical vapor deposition or chemical vapor deposition. Further, a barrier resin film or glass may be provided as a barrier film.

  Thus, since the light emitting display device 11 including the organic EL element has the organic EL layer 6 on the transparent first electrode 5 of the optical substrate 10 according to the present invention described above, the organic EL layer 6 emits light. When the incident light enters the translucent substrate 1 side from the first electrode 5, the light is refracted or reflected by the light scattering particles 4 included in the light scattering layer 3, and part of the light is transmitted from the translucent substrate 1. Take out to the outside. Further, another part of the light refracted or reflected by the light scattering particles 4 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3 or is reflected by the light scattering wall 2. The light is refracted or reflected, and a part of the light is extracted from the translucent substrate 1 to the outside. Further, another part of the light refracted or reflected by the light scattering wall 2 travels in the light scattering layer 3 and is refracted or reflected again by the light scattering particles 4 included in the light scattering layer 3, and part of the light is transmitted. It is taken out from the optical substrate 1 to the outside. By repeating such refraction or reflection at the light scattering particles 4 and the light scattering wall 2, light incident on the light transmissive substrate 1 side from the first electrode 5 is efficiently extracted from the light transmissive substrate 1.

  Such a light emitting display device 11 may constitute a passive matrix organic EL device, or may constitute an active matrix organic EL device together with a thin film transistor circuit.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The scope of the present invention is not limited to the following examples.

[Example 1]
A glass substrate having a thickness of 0.7 mm was used as the translucent substrate 1, and the light scattering wall 2 was formed on the translucent substrate 1. The light scattering wall 2 is formed by applying a photosensitive insulating material (manufactured by Toray Industries, Inc., product name: DL-1602) by a spin coat method and then heating to form a film, and then exposing and developing to form a pitch of 125 μm and a width. It was formed to have a thickness of about 20 μm and a height of about 0.5 μm. The refractive index n3 of the light scattering wall 2 was about 1.6.

  A thermosetting resin (manufactured by DNP Fine Chemical Co., Ltd., product name: IT-MP1916) was spin-coated on the translucent substrate 1 on which the light scattering wall 2 was formed so that the thickness after curing was about 1 μm. Thereafter, exposure was performed with an integrated light amount of 100 mJ without pre-baking. After the exposure, the light scattering layer 3 was formed by heating at 230 ° C. for 30 minutes. In the light scattering layer 3 after the formation, a large number of light scattering particles 4 in which bubble particles were generated during heating were generated. The light scattering layer 3 has a refractive index n2 of about 1.7, which is larger than the refractive index n3 of the light scattering wall 2 described above. In addition, the refractive index n1 in the light scattering particle 4 is about 1.0. Moreover, the size of the light scattering particles 4 was about 5 to 8 μm in diameter. When the number of light scattering particles 4 was examined with a microscope, 208 particles were present in an area of 100 μm × 100 μm.

  A transparent electrode 5 was formed on the light scattering layer 3. The transparent electrode 5 was formed by sputtering a 200 nm thick IZO film on the light scattering layer 3. Thus, an optical substrate 10A having the form shown in FIG. 1 was produced.

Next, the organic EL layer 6 was formed on the transparent electrode 5. The organic EL layer 6 is provided with MoO ₃ (thickness: 30 nm) as the hole injection layer 6a and NPD (thickness: 120 nm) as the hole transport layer 6b by the vacuum film forming means by resistance heating in order. NPD (thickness 20 nm) was provided as 6c, Alq3 (thickness 60 nm) was provided as the electron transport layer 6d, and LiF (thickness 2 nm) was provided as the electron injection layer 6e. Further thereon, Al (thickness: 300 nm) was provided as a cathode as the second electrode 7. At this time, the film forming rate of each material by the vacuum film forming means is MoO ₃ : 0.2 to 0.25 Å / s, NPD: 0.8 to 1.0 Å / s, Alq3: 0.2 Å / s, LiF : 0.1 Å / s, Al: 5.0 Å / s. Thus, a light emitting display device in which the organic EL layer 6 was formed on the optical substrate 10A was produced.

  Thereafter, a glass substrate was used as a sealing member, and the glass substrate was provided on the cathode as the second electrode 7 through an ultraviolet curable resin (manufactured by Kyoritsu Chemical Co., Ltd.) and sealed.

[Example 2]
A light emitting display device of Example 2 was fabricated in the same manner as in Example 1 except that the thickness of the light scattering layer 3 was changed to 60 μm in Example 1.

[Comparative Example 1]
In Example 1, the light scattering wall 2 is not formed on the translucent substrate 1 and the light scattering layer 3 having the light scattering particles 4 is not formed. A light-emitting display device was manufactured. In this light-emitting display device, a first electrode 5 is provided on a translucent substrate 1, MoO ₃ (thickness 30 nm) is provided as a hole injection layer 6a on the transparent electrode 5, and a hole transport layer 6b. NPD (thickness 120 nm) is provided, NPD (thickness 20 nm) is provided as the light emitting layer 6c, Alq3 (thickness 60 nm) is provided as the electron transport layer 6d, and LiF (thickness 2 nm) is provided as the electron injection layer 6e. Further, a sealing member was provided.

[Comparative Example 2]
In Example 1, the light scattering wall 2 was not formed on the translucent substrate 1, but only the light scattering layer 3 having the light scattering particles 4 was formed. A light-emitting display device was manufactured.

[Comparative Example 3]
In Example 1, although the light-scattering wall 2 was formed on the translucent substrate 1, the light-scattering layer 3 in which the light-scattering particle 4 was not formed was formed. Other than that was carried out similarly to Example 1, and produced the light emission display device of the comparative example 3. FIG. The light scattering layer 3 on which the light scattering particles 4 are not formed is spin-coated so that the thickness after curing a thermosetting resin (DNP Fine Chemical Co., Ltd., product name: IT-MP1916) is about 1 μm. Then, after prebaking at 120 ° C., exposure was performed with an integrated light amount of 100 mJ, and then heating was performed at 230 ° C. for 30 minutes, whereby the light scattering layer 3 without the light scattering particles 4 was formed.

[Brightness measurement results]
For the light emitting display devices of Examples 1 and 2 and Comparative Examples 1 to 3, the luminance was measured at an equivalent current value (2.3 A) using a luminance measuring device (manufactured by Topcon Corporation, product name: BM-8). did. As a result, the luminance of the light-emitting display device of Example 1 was 1102 cd / m ² , and the luminance of the light-emitting display device of Example 2 was 1152 cd / m ² . On the other hand, the luminance of the light emitting display device of Comparative Example 1 is 825 cd / m ² , the luminance of the light emitting display device of Comparative Example 2 is 930 cd / m ² , and the luminance of the light emitting display device of Comparative Example 3 is 910 cd / m ^2. Met. The light emission luminance of the light emitting display device of Example 1 is about 34% higher than the light emission luminance of the light emission display device of Comparative Example 1, and about 18% higher than the light emission luminance of the light emission display device of Comparative Example 2. Thus, it was confirmed that the brightness of the light emitting display device of Comparative Example 3 was improved by about 21%. From this result, by forming the light scattering wall 2 on the translucent substrate 1 and further forming the light scattering layer 3 having the light scattering particles 4, the luminance is improved, and the light incident on the light scattering layer 3 is reduced. It was found that the light-transmitting substrate 1 was efficiently taken out.

DESCRIPTION OF SYMBOLS 1 Translucent substrate 2 Light scattering wall 3 Light scattering layer 4 Light scattering particle 5 Transparent electrode (1st electrode)
6 organic EL layer 6A hole injection transport layer 6B light emitting layer 6C electron injection transport layer 6a hole injection layer 6b hole transport layer 6c light emission layer 6d electron transport layer 6e electron injection layer 7 second electrode 10 optical substrate 11 light emitting display device

Claims (11)

  A light-transmitting substrate, a plurality of light-scattering walls provided on the light-transmitting substrate, a light-scattering layer provided on the light-transmitting substrate and covering the light-scattering wall, and on the light-scattering layer An optical substrate comprising: a transparent electrode provided; and the light scattering layer having a plurality of light scattering particles.   The optical substrate according to claim 1, wherein the light scattering particles are bubble particles.   The optical substrate according to claim 1 or 2, wherein a height of the light scattering wall is 50% or more and 90% or less of a thickness of the light scattering layer.   The optical substrate according to claim 1, wherein a refractive index of the light scattering wall is smaller than a refractive index of the light scattering layer.   The optical substrate according to any one of claims 1 to 4, wherein a refractive index in the light scattering particles is smaller than a refractive index of the light scattering layer other than the light scattering particles.   Forming a plurality of light scattering walls on the light transmissive substrate, forming a light scattering layer having a plurality of light scattering particles on the light transmissive substrate and covering the light scattering wall, and And a step of forming a transparent electrode on the light scattering layer.   The light diffusing particles of the light scattering layer are coated with a resin that cures with one or both of heat and active energy rays so as to cover the light scattering wall on the light transmissive substrate, and then the heat and activity. The method for producing an optical substrate according to claim 6, which is generated as bubble particles in the light scattering layer made of the resin when cured with one or both of energy rays.   8. The optical substrate according to claim 6, wherein the light scattering wall is patterned after applying a light-transmitting resin and formed to a height of 50% to 90% of the thickness of the light scattering layer. Production method.   A light-transmitting substrate, a plurality of light-scattering walls provided on the light-transmitting substrate, a light-scattering layer provided on the light-transmitting substrate and covering the light-scattering wall and having a plurality of light-scattering particles And a light emitting body provided on the light scattering layer.   The luminous body includes a transparent first electrode provided on the light scattering layer, an organic EL layer provided on the first electrode, and a second electrode provided on the organic EL layer. The light-emitting display device according to claim 9.   A light transmissive substrate, a plurality of light scattering walls provided on the light transmissive substrate, and a light scattering layer having a plurality of light scattering particles provided on the light transmissive substrate and covering the light scattering wall And the height of the light scattering wall is not less than 50% and not more than 90% of the thickness of the light scattering layer.

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