JP2011082032A - Scattering prevention sheet, el element equipped with the same, and el light-emitting device equipped with the el element as light-emitting source - Google Patents

Abstract

Provided is an integrated stack on a light-transmitting substrate of an EL element, and prevents the substrate pieces from scattering when the light-transmitting substrate is damaged, and also the light use efficiency of the EL element, EL An anti-scattering sheet that contributes to an improvement in light utilization efficiency (light emission efficiency) of a device including an element, an EL element using the sheet, and an EL device such as a lighting device, a display device, and a display device including the EL element as a light source A light emitting device is provided.
An anti-scattering sheet 7 is provided which is integrally laminated on a translucent substrate 6 of an EL element A, and prevents the substrate pieces from scattering when the translucent substrate 6 is damaged. The surface 7c side is formed with a plurality of geometrically arranged concave portions 11 and convex portions 12 so that the light H transmitted from the translucent substrate 6 side is emitted outward from the surface 7c.
[Selection] Figure 1

Description

  The present invention is provided with an anti-scattering sheet for preventing a substrate piece from being scattered when the EL substrate is integrally laminated on a light-transmitting substrate of an EL element and the light-transmitting substrate is damaged. The present invention relates to an EL element, and an EL light-emitting device such as an illumination device, a display device, or a display device provided with the EL element as a light source.

  2. Description of the Related Art Conventionally, some display devices (EL light emitting devices) such as lighting devices, display devices such as electrical decorations and sign light sources, and flat panel displays use EL elements as light emission sources. In general, as shown in FIG. 3, this type of EL element 1 includes an EL element body 5 formed by sandwiching a light emitting layer 2 containing a fluorescent organic compound between an anode 3 and a cathode 4 (a pair of electrode layers 3 and 4). The EL element body 5 is integrally laminated on one surface (incident surface, incident surface side surface) 6 a of the translucent substrate 6. In the EL element 1, when a DC voltage is applied between the pair of electrode layers 3 and 4, electrons and holes are injected, the light emitting layer 2 emits light, and the light H generated in the light emitting layer 2 is transmitted. The light enters the conductive substrate 6 and is transmitted through and emitted from the other surface (exit surface, output surface side surface) 6b.

  Conventionally, the EL element 1 has a structure in which the light-transmitting substrate 6 is formed using glass or the like, and the device including the EL element 1 as a light source has the light-transmitting substrate 6 disposed on the outermost surface. There are many things that have been done. However, the device configured as described above has a problem that the substrate piece (glass piece) is scattered when the translucent substrate 6 is damaged due to the dropping of the device or direct impact. For this reason, the EL device 1, the lighting device, the display device, and the display device including the EL device 1 have a scattering prevention sheet or the like so that the substrate piece does not fly even when the translucent substrate 6 is damaged. There exists what comprised the scattering prevention cover (for example, refer patent document 1).

  The anti-scattering sheet includes a base layer made of a transparent resin film and an adhesive layer provided on the surface of the base layer, and the surface of the translucent substrate 6 (one surface 6a or the other surface) is an adhesive layer. By sticking to 6b), scattering of the substrate piece is prevented. In addition, a transparent acrylic cover, a glass cover, etc. are used for a scattering prevention cover, and it prevents scattering of a board | substrate piece by installing so that the translucent board | substrate 6 may be coat | covered.

JP 2003-92014 A

  By the way, in the conventional EL element 1 having the above configuration, a part of the light H generated in the light emitting layer 2 and transmitted through the light transmissive substrate 6 (many light H) is transmitted through the light transmissive substrate 6. Since the light is totally reflected by the light exit surface 6b, a loss of light H occurs. Moreover, since the refractive index of ITO generally used as the anode (one electrode layer) 3 is higher than the refractive index of the translucent substrate 6 (the refractive index of ITO N = 2.7, the refraction of the translucent substrate 6). Rate N = 1.5), even on the incident surface 6 a of the light transmitting substrate 6, a part of the light H incident on the light transmitting substrate 6 is transmitted by the difference in refractive index between the anode 3 and the light transmitting substrate 6. Light is totally reflected at the incident surface 6a of the conductive substrate 6 and a loss of light H occurs. The light H is lost due to the total reflection at the exit surface 6b and the entrance surface 6a of the translucent substrate 6 in this way, so that the light extraction efficiency from the EL element 1 and thus the device provided with the EL element 1 are increased. The light utilization efficiency (light emission efficiency) of the battery becomes low. In addition, if the light utilization efficiency of the device is low, it is necessary to input a large amount of power in order to obtain a required luminance, and the load applied to the EL element 1 becomes large.

  Furthermore, since the scattering prevention sheet is used by being attached to the surfaces 6a and 6b (panel portions of various devices) of the translucent substrate 6 of the EL element 1, if the transparency is low, the light utilization efficiency (luminous efficiency) of various devices. However, the conventional scattering prevention sheet is provided only for the purpose of preventing the scattering of the substrate piece due to the breakage of the translucent substrate 6, and has a function to improve the light utilization efficiency of the apparatus. Therefore, the light utilization efficiency can be lowered from this point.

  In the conventional scattering prevention sheet, the scattering prevention performance of the substrate piece (glass piece) depends on the adhesive strength of the adhesive layer (adhesive) to the translucent substrate 6. And if adhesive strength is made too high so that scattering of a board | substrate piece can be prevented, removability will worsen. For this reason, there are many cases where it is necessary to re-attach (rework) due to foreign matter biting into the anti-scattering sheet. However, the adhesive strength of the adhesive layer is too high, and adhesive residue and cells are re-worked. In some cases, a change in the gap occurred and the EL element 1 (panel portion) was damaged.

  Furthermore, the ITO used for the anode 3 of the EL element 1 is conventionally produced for each sheet in a batch system, and is improved against the loss of light H due to a large refractive index difference from the translucent substrate 6. In addition, there is a strong demand for improvement in the process of the EL element 1 with respect to the anode 3 and, in turn, improvement in the cost of the EL element 1.

  In view of the above circumstances, the present invention is provided by integrally laminating a light-transmitting substrate of an EL element, and prevents the substrate pieces from scattering when the light-transmitting substrate is damaged. Scattering efficiency sheet which contributes also to improvement of light utilization efficiency of light, efficiency of light utilization (light emission efficiency) of device equipped with EL element, EL element using the same, and illumination device and display device comprising this EL element as light emission source An object of the present invention is to provide an EL light emitting device such as a display device.

  In order to achieve the above object, the present invention provides the following means.

  The anti-scattering sheet of the present invention is provided by being integrally laminated on the light-transmitting substrate of the EL element, and the anti-scattering sheet for preventing the substrate pieces from scattering when the light-transmitting substrate is damaged. The surface side is formed with a plurality of concave portions and convex portions that are geometrically arranged so as to emit light transmitted from the light transmissive substrate side to the outside. To do.

  In the present invention, the scattering prevention sheet provided integrally laminated on the light-transmitting substrate of the EL element can prevent the substrate pieces from scattering even when the light-transmitting substrate is damaged. . In addition, since the scattering prevention sheet is formed with a plurality of concave portions and convex portions that are geometrically arranged on the surface side, the light that can be lost by being reflected on the light emitting surface side surface of the translucent substrate. It can be taken out from the concave or convex portion of the anti-scattering sheet so as to be emitted outward from the surface and used as outgoing light.

  In the scattering prevention sheet of the present invention, the plurality of concave portions and / or convex portions are arranged at a constant pitch or randomly in a direction along the translucent substrate.

  In the present invention, the plurality of concave portions and / or convex portions are arranged at a constant pitch in the direction along the light-transmitting substrate, so that light that can be reflected and lost on the light-emitting surface side surface of the light-transmitting substrate. Can be extracted and used as effective emitted light by the concave portion or convex portion on the surface side of the anti-scattering sheet. Further, even when a plurality of concave portions and / or convex portions are randomly arranged, light that can be lost can be effectively extracted by these concave portions or convex portions and used as emitted light.

  Furthermore, in the scattering prevention sheet of the present invention, it is preferable that the plurality of concave portions and / or convex portions are formed in a pyramid shape, a conical shape, a spherical shape, or a shape obtained by combining two or more of these shapes.

  In the present invention, the plurality of concave portions and / or convex portions are formed in a pyramid shape, a conical shape, a spherical shape, or a shape in which two or more of these shapes are combined, so that the surface on the exit surface side of the translucent substrate is used. Light that can be reflected and lost can be extracted and reliably used as outgoing light.

  The EL element of the present invention is formed by sandwiching a light-transmitting substrate and a light emitting layer between a transparent anode and a cathode, and arranging the anode on one surface side of the light-transmitting substrate so as to be integrated with the light-transmitting substrate. In an EL element comprising a laminated EL element body, any one of the above scattering prevention sheets provided integrally laminated on the other surface side of the translucent substrate, the translucent substrate, and the translucent substrate An antireflection layer provided between the anodes of the EL element main body and an antireflection layer provided between the translucent substrate and the anti-scattering sheet so as to integrate the translucent substrate and the anti-scattering sheet. A first adhesive layer; and a second adhesive layer that is provided between the translucent substrate and the antireflection layer and integrates the translucent substrate and the antireflection layer. It is characterized by.

  In this invention, since the scattering prevention sheet according to the present invention is provided on the other surface side of the light-transmitting substrate, the other surface of the light-transmitting substrate, that is, the light-emitting surface (light-emitting surface side surface) of the light-transmitting substrate. It is possible to suppress the occurrence of light loss due to reflection at. Further, since an antireflection layer is provided between the translucent substrate and the EL element body, light is reflected by reflection on the one surface of the translucent substrate, that is, the incident surface (incident surface side surface) of the translucent substrate. It is possible to suppress the occurrence of loss. This makes it possible to improve the light extraction efficiency as compared with the conventional EL element.

  In the EL element of the present invention, the antireflection layer is formed by forming the antireflection film on the translucent substrate, or forming an antireflection film on the anode of the EL element body, or on a transparent substrate. It is desirable to form the antireflection film and to include one or multiple layers of the antireflection layer.

  In this invention, an antireflection film is formed on a translucent substrate, an antireflection film is formed on the anode of the EL element body, or an antireflection film is formed on a transparent substrate. By providing the antireflection layer, it is possible to reliably suppress the occurrence of light loss due to reflection on the incident surface of the translucent substrate, and it is possible to improve the light extraction efficiency.

  Furthermore, in the EL device of the present invention, it is more desirable that the second adhesive layer has a rough surface so that a groove having a width and a depth less than the wavelength of the light generated in the light emitting layer is formed. .

  In the present invention, the surface of the second adhesive layer is roughened so that a groove having a width and a depth less than the wavelength of light generated in the light emitting layer is formed. Therefore, it is possible to suppress the occurrence of light loss due to reflection, and it is possible to improve the light extraction efficiency more reliably.

  An EL light-emitting device of the present invention is an apparatus including an EL element as a light source, and the EL element is any one of the above EL elements.

  In the present invention, for example, an EL element of an apparatus provided with an EL element as a light source, such as a lighting device, a display device, and a display device, is an EL element according to the present invention having excellent light extraction efficiency, so that light utilization efficiency (light emission) Efficiency) can be improved.

  In the anti-scattering sheet of the present invention, even when the translucent substrate is damaged, the substrate piece can be prevented from scattering, and a plurality of concave and convex portions arranged geometrically on the surface side Accordingly, light that can be lost by being reflected on the light-emitting surface side surface of the translucent substrate can be used as light emitted by the concave portion or the convex portion on the surface side of the scattering prevention sheet.

  In addition, in the EL element of the present invention, the scattering prevention sheet according to the present invention has a function of not only preventing the scattering of the substrate piece due to the breakage of the translucent substrate but also reducing the light loss. Compared with the EL element, the light extraction efficiency of the EL element can be improved. Furthermore, since an antireflection layer is provided between the light-transmitting substrate and the anode of the EL element body, it is possible to reduce light loss even with this antireflection layer. The extraction efficiency can be further improved.

  In addition, when ITO is used for the anode of the EL element, using a film-like transparent substrate and performing continuous production in a roll-to-roll manner, the process can be simplified compared to the conventional batch method for each sheet. This can be realized, and it becomes possible to improve the process of the EL element with respect to the anode, and hence the cost of the EL element.

  Furthermore, since the EL light emitting device of the present invention includes the EL element according to the present invention having excellent light extraction efficiency as described above, the EL element of a conventional lighting device, display device, display device, or the like is used as a light source. As compared with the EL light emitting device provided as the light emitting device, it is possible to improve the light use efficiency (light emission efficiency) and to improve the performance of the EL light emitting device such as the luminance.

It is a figure which shows the EL element which concerns on one Embodiment of this invention. It is a figure which shows the scattering prevention sheet | seat which concerns on one Embodiment of this invention. It is a figure which shows the conventional EL element.

  Hereinafter, with reference to FIG.1 and FIG.2, the scattering prevention sheet | seat, EL element, and EL light-emitting device which concern on one Embodiment of this invention are demonstrated.

  The EL light emitting device of the present embodiment is, for example, a lighting device, a display device such as an electric decoration or a sign light source, or a display device such as a flat panel display, and includes an EL element A as a light source.

  As shown in FIG. 1, the EL element A of the present embodiment includes a translucent substrate 6, an EL element body 5, a scattering prevention sheet 7, an antireflection layer 8, a first adhesive layer 9, The second adhesive layer 10 is provided.

  The translucent substrate 6 is provided to ensure the barrier property of various EL light emitting devices, and is a transparent substrate such as glass like the translucent substrate 6 used in the conventional EL element 1. . The translucent substrate 6 can be made of a plastic material such as PMMA, polycarbonate, polystyrene, etc. in addition to various glass materials, and is made of a transparent material that can ensure the barrier properties of various EL light emitting devices. If it is formed, there is no particular limitation. The translucent substrate 6 transmits all light so that light H generated in the light emitting structure (the light emitting layer 2 of the EL element body 5) can be transmitted with as little loss (light loss) as possible. It is preferable to use a material capable of making the rate 50% or more.

  The EL element body 5 is formed by integrally laminating a transparent anode 3 and a cathode 4 (a pair of electrode layers 3 and 4) on both sides of the light emitting layer 2. The EL element body 5 is disposed on the one surface (incident surface side surface 6 a) side of the translucent substrate 6. At this time, the anode (one electrode layer) 3 is disposed on the one surface 6 a side of the translucent substrate 6. Are laminated together. The light emitting layer 2 of the present embodiment is a white light emitting layer that emits white light by injecting electrons and holes when a DC voltage is applied between the pair of electrode layers 3 and 4. The light emitting layer 2 that emits white light H is, for example, ITO / CuPc (copper phthalocyanine) / α-NPD doped with rubrene 1% / dinactylanthracene doped with berylene 1% / Alq3 / lithium fluoride / Al. It consists of At this time, ITO becomes the transparent anode 3 and Al becomes the cathode 4. The light emitting layer 2 may emit light H such as blue, red, yellow, and green. In this case, the wavelength of the emitted light is R (red), G (green), B What is necessary is just to comprise using the material suitably made into (blue). Further, when used in a full-color display application, full-color display is possible by separately coating three types of light-emitting materials corresponding to R, G, and B, or by overlapping a color filter on the white light-emitting layer 2.

  The ITO of the anode 3 is formed by a dry process such as vapor deposition or sputtering using a film-like transparent substrate. Processes can be simplified and cost can be improved by continuous production using toll-to-roll on a film-like substrate instead of batch-by-sheet.

  As shown in FIGS. 1 and 2, the scattering prevention sheet 7 of the present embodiment is formed by integrally laminating a resin uneven layer 7b on a transparent substrate 7a. And this scattering prevention sheet 7 is arrange | positioned at the other surface (outgoing surface side surface 6b) side of the translucent board | substrate 6. FIG. At this time, the base material 7a is disposed on the other surface 6b side of the translucent substrate 6, and the surface 7c of the concavo-convex layer 7b is directed to the outside in the laminating direction T1 so as to be integrally laminated via the first adhesive layer 9. ing. That is, the scattering prevention sheet 7 is integrated on the other surface 6 b side of the light transmitting substrate 6 via the first adhesive layer 9 provided between the light transmitting substrate 6 and the scattering prevention sheet 7. .

  The uneven layer 7b (the surface 7c of the anti-scattering sheet 7) has a plurality of recesses geometrically arranged on the surface 7c side so that the light H transmitted from the translucent substrate 6 side is emitted from the surface 7c to the outside. 11 and a convex portion 12. Further, in the present embodiment, the plurality of concave portions 11 and the convex portions 12 (the concave portions 11 and / or the convex portions 12) are each formed in a pyramid shape, and are arranged at a constant pitch in the direction T2 along the translucent substrate 6. ing. In addition, if the some recessed part 11 and / or the convex part 12 can be made to radiate | emit the light H permeate | transmitted from the translucent board | substrate 6 side to the outer side from the surface 7c, it will be in the direction T2 along the translucent board | substrate 6. They may be arranged at random, or may be formed in a shape combining two or more of these shapes, including a conical shape, a spherical shape, or a pyramid shape.

  Moreover, in the scattering prevention sheet 7 of this embodiment, the base material 7a is, for example, PET (polyethylene terephthalate), PC (polycarbonate), PMMA (polymethylmetalate), COP (cycloolefin polymer), acrylonitrile styrene copolymer. Etc. are used to form a sheet by an injection molding method or a hot press molding method. Moreover, as for the base material 7a, it is desirable that the thickness is 20 micrometers-1000 micrometers. That is, if the thickness is less than 20 μm, the base material 7a may be damaged when the translucent substrate 6 is damaged, and the effect of preventing the scattering of the substrate pieces may not be exhibited. If the thickness exceeds 1000 μm, the productivity is increased. May be damaged.

  And when forming this scattering prevention sheet | seat 7, it uses an ultraviolet curing type | mold on the transparent base material 7a using the cylinder metal mold | die cut according to the shape of the uneven | corrugated layer 7b. Apply resin. Next, the UV curable resin is cured by exposing UV light from the transparent substrate 7a side. By releasing the mold after curing of the ultraviolet curable resin, the concave / convex layer 7b of the ultraviolet curable resin having the necessary concave portions 11 and convex portions 12 on the surface 7c is integrally laminated on the base material 7a. A scattering prevention sheet 7 is formed.

  Here, the ultraviolet curable resin is a resin having an acryloyl group in the molecule, and is synthesized with epoxy acrylate, urethane acrylate, polyester acrylate, polyol acrylate oligomer, polymer and monofunctional, bifunctional or polyfunctional medium. (Meth) acrylate monomers such as tetrahydrofurfuryl acrylate, 2-hydroxyethyl acrylate, polypropylene glycol diacrylate, trimethylol broban triacrylate, bentaerythritol triacrylate, bentamerythritol tetraacrylate, monomers, oligomers, polymers, etc. A mixture is used.

  In addition, as a compound in the ultraviolet curable resin liquid, a photopolymerization initiator such as benzophenone, diethylthioxanthone, benzyldimethyl ketal, 2-hydroxy-2-methyl-1-phenylbroban-1-one, 1-hydroxycyclohexyl There are finyl ketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinobroban-1, acylphosphine oxide, and the like. On the other hand, such a photopolymerization initiator does not react 100%, and an unreacted photopolymerization initiator may remain and a resin layer may be molded. There is a risk of adverse effects. For this reason, the photopolymerization initiator is added in the range of 0.1 to 7% by weight, preferably in the range of 0.5 to 5% by weight, and the unreacted part is not left as much as possible, which adversely affects the unevenness performance. It is necessary to prevent this from happening.

  Moreover, you may mix | blend a diluent with an ultraviolet curable resin liquid as needed. Examples of the diluent include organic solvents such as acetone, ethanol, methanol, ethyl acetate, chloroform, carbon tetrachloride, tetrahydrofuran, cyclohexane, diethyl ether, methyl ethyl ketone, toluene, and benzene.

  Further, other additives include ultraviolet absorbers, light stabilizers, surfactants, antifoaming agents, antistatic agents, antioxidants, flame retardants and the like. And it is necessary to select those additives that do not adversely affect the performance of the unevenness to be molded, or to add them in an additive amount that does not adversely affect them.

  As shown in FIG. 1, the antireflection layer 8 of the present embodiment is for suppressing the light H generated in the light emitting layer 2 from being reflected by the incident surface side surface 6 a of the translucent substrate. An antireflection film 8b is formed on the substrate 8a. The antireflection layer 8 is disposed on one surface (incident surface side surface 6 a) side of the translucent substrate 6 and is laminated between the translucent substrate 6 and the anode 3 of the EL element body 5. ing. At this time, in the present embodiment, the antireflection layer 8 is arranged with the transparent base material 8a on the one surface 6a side of the translucent substrate 6, and the antireflection film 8b is arranged on the anode 3 side of the EL element body 5, It is provided between the translucent substrate 6 and the EL element body 5. Further, the antireflection layer 8 is integrated with the one surface 6 a side of the translucent substrate 6 through a second adhesive layer 10 provided between the translucent substrate 6 and the antireflection layer 8.

Here, the formation method of the antireflection layer 8 (the formation method of the antireflection film 8b) includes a wet method and a dry method. In the dry method, inorganic materials such as TiO ₂ and ZrO ₂ which are high refractive index materials are used. The compound is deposited by vacuum deposition or sputtering. On the other hand, in the wet method, the film is formed using a sol-gel method in which an inorganic thin film is formed by hydrolysis or condensation reaction of metal alkoxide, or a coating method in which a solvent is decomposed and evaporated to form an organic thin film. Here, since the dry method requires special conditions such as vacuum and high temperature, it is difficult in terms of cost and mass production. In contrast, spin coating, sol dipping - With gel method (wet method), it is possible to form a thin film of the medium refractive index from a mixture such as a thin film of high bending modulus by TiO ₂ or TiO ₂ and silica, . In addition, a thin film such as a benzene ring, Br, or S can be formed by a coating method (wet method) such as gravure coating or die coating. For this reason, it can be said that the antireflection layer 8 is preferably formed (formed) using a wet method. Further, at this time, the total reflection of the light H can be reduced by roughening the surface 8c of the antireflection layer 8 (antireflection film 8b) in the same manner as the second adhesive layer 10 described later in detail. Then, by interposing the antireflection layer 8 formed in this way, the refractive index difference between the ITO of the anode 3 and the translucent substrate 6 is substantially reduced, and the light H from the light emitting layer 2 is transmitted. Loss of light H generated when passing through the optical substrate 6 is reduced.

  The antireflection layer 8 may be formed by forming the antireflection film 8b on the anode 3 of the EL element body 5 without using the transparent substrate 8a. Further, the antireflection film 8b may be formed directly on the one surface 6a of the transparent substrate 6 by a dry method or a wet method without using the transparent substrate 8a. Alternatively, a film having a refractive index higher than that of the transparent base material 8 a such as PET (polyethylene terephthalate) or PC (polycarbonate) may be used as the antireflection layer 8, and the film may be bonded only via the second adhesive layer 10. The effect of suppressing the loss of light H due to total reflection is obtained. Furthermore, the antireflection layer 8 need not be limited to being formed of a single layer, and may be formed of multiple layers.

  The first adhesive layer 9 and the second adhesive layer 10 used for bonding the scattering prevention sheet 7 and the antireflection layer 8 are formed using an adhesive or an adhesive. Urethane, acrylic, rubber, silicone, and vinyl resins can be used for the adhesive and adhesive. In addition, as the pressure-sensitive adhesive or adhesive, one that is bonded by pressing with one liquid type, one that is cured by heat or light, and one that is cured by mixing two liquids or a plurality of liquids are used. Can do. Further, as a method of forming the adhesive layers 9 and 10, a method of directly applying to the adhesive surface or a method of pasting together those prepared in advance as a dry film is applied. And when preparing the 1st contact bonding layer 9 and the 2nd contact bonding layer 10 as a dry film, it becomes possible to handle easily on a manufacturing process. In this case, the adhesive strength is 4 to 30 N / inch. If it is less than 4 N / inch, there is a possibility that sufficient anti-scattering performance may not be exhibited. If it exceeds 30 N / inch, the yield of the panel is reduced due to adhesive residue during rework, and the workability of rework is reduced. It becomes a factor of the yield fall at the time of production of EL light-emitting device.

  Further, the second adhesive layer 10 provided between the transparent substrate 6 and the antireflection layer 8 has a surface so that a groove having a width and a depth less than the wavelength of the light H generated in the light emitting layer 2 is formed. It has been devastated. Thereby, it is suppressed that the light H generated in the light emitting layer 2 is reflected at the interface.

  A diffusion filler may be added to the first adhesive layer 9 and the second adhesive layer 10. In this case, by diffusing the light H generated from the light emitting layer 2 with the diffusion filler, the antiglare property of the target device is increased, and the effect of reducing color unevenness, color misregistration, and the like is obtained. As the diffusion filler, transparent particles made of an inorganic oxide or a resin can be used. Transparent particles made of inorganic oxide include acrylic particles, styrene particles, styrene acrylic particles and their crosslinked products, melamine-formalin condensate particles, PTFE (polytetrafluoroethylene), PFA (perfluoroalkoxy resin), FEP (tetra Fluoropolymer resins such as fluoroethylene / hexafluoropropylene copolymer), PVDF (polyfluorovinylidene), and ETFE (ethylene / tetrafluoroethylene copolymer), silicone resin particles, and the like can be used. Moreover, you may use combining 2 or more types of transparent particles from the transparent particle mentioned above. Furthermore, the size and shape of the transparent particles need not be particularly limited.

  In the scattering prevention sheet 7 of the present embodiment having the above-described configuration, the EL element A including the same, and the EL light emitting device including the EL element A as a light source, the scattering prevention sheet is provided on the translucent substrate 6 of the EL element A. 7 is integrally laminated, the substrate piece may be scattered even when the EL light emitting device is dropped or the impact is directly applied to the translucent substrate 6. Is prevented.

  Further, since the scattering prevention sheet 7 includes a plurality of concave portions 11 and convex portions 12 that are geometrically arranged on the surface 7c side, it can be reflected by the light exit surface 6b of the translucent substrate 6 to cause a loss. The light H is extracted as emitted light H by the concave portion 11 or the convex portion 12 on the surface 7 c side of the scattering prevention sheet 7. Further, at this time, the plurality of concave portions 11 and / or convex portions 12 are arranged at a constant pitch (or random) in the direction T2 along the translucent substrate 6, so that the light H that can be lost is effectively obtained. It is extracted as outgoing light H. Further, the light emitted from the translucent substrate 6 can also be obtained by forming the plurality of concave portions 11 and / or convex portions 12 in a pyramid shape (or a conical shape, a spherical shape, or a combination of two or more of these shapes). The light H that can be lost by being reflected by the surface-side surface 6b is reliably extracted as the outgoing light H.

  Further, since the antireflection layer 8 is provided between the translucent substrate 6 and the EL element body 5, the transmitted light H is one surface 6 a of the translucent substrate 6, that is, the incident surface of the translucent substrate 6. Reflection at (incident surface side surface) is suppressed.

  Further, the surface of the second adhesive layer 10 is roughened so that a groove having a width and a depth less than the wavelength of the light H generated in the light emitting layer 2 is formed. The reflection of the light H on the surface is also suppressed.

  Thereby, compared with the conventional EL element 1, the light extraction efficiency of the EL element A is improved, and an illumination device, a display device, a display device, and the like provided with the EL element A having the excellent light extraction efficiency as a light source. Compared with a conventional EL light emitting device, the EL light emitting device has improved light utilization efficiency (light emission efficiency) and performance such as luminance.

  Therefore, in the anti-scattering sheet 7 of this embodiment, even if the translucent substrate 6 is damaged by being integrally laminated on the translucent substrate 6 of the EL element A, the substrate piece Can be prevented from scattering. Further, since the scattering prevention sheet 7 is formed with a plurality of concave portions 11 and convex portions 12 geometrically arranged on the surface 7c side, it is reflected on the light exit surface side surface 6b of the translucent substrate 6. Thus, the light H that can be lost can be extracted from the concave portion 11 or the convex portion 12 of the scattering prevention sheet 7 so as to be emitted from the surface 7c to the outside, and can be used as the outgoing light H.

  Further, since the plurality of concave portions 11 and / or convex portions 12 are arranged at a constant pitch in the direction T2 along the translucent substrate 6, the light is reflected on the light exit surface 6b of the translucent substrate 6 and lost. The light H that can be obtained can be effectively extracted and used as the emitted light H by the concave portion 11 or the convex portion 12 of the scattering prevention sheet 7. Further, even when the plurality of concave portions 11 and / or convex portions 12 are randomly arranged, the light H that can be lost is effectively extracted by the concave portions 11 or the convex portions 12 and used as the emitted light H. It becomes possible.

  Further, the plurality of concave portions 11 and / or convex portions 12 are formed in a pyramid shape, a conical shape, a spherical shape, or a shape obtained by combining two or more of these shapes, whereby the exit surface side surface 6b of the translucent substrate 6 is formed. Therefore, it is possible to extract the light H that can be reflected and lost, and to reliably use it as the outgoing light H.

  Further, in the EL element A of the present embodiment, since the anti-scattering sheet 7 having the above-described effects is provided on the other surface (outgoing surface side surface) 6b side of the translucent substrate 6, the translucent substrate It is possible to suppress the loss of the light H due to the reflection on the other surface 6 b of 6, that is, the exit surface (exit surface side surface) of the translucent substrate 6. Further, since the antireflection layer 8 is provided between the translucent substrate 6 and the EL element body 5, one surface 6a of the translucent substrate 6, that is, the incident surface (incident surface side surface) of the translucent substrate 6. It is also possible to suppress the loss of the light H due to the reflection at. Thereby, it is possible to improve the light extraction efficiency as compared with the conventional EL element 1.

  Further, an antireflection film 8b is formed on the translucent substrate 6, or an antireflection film 8b is formed on the anode 3 of the EL element body 5, or an antireflection film 8b is formed on the transparent substrate 8a. By providing the antireflection layer 8 having multiple layers or multiple layers, it is possible to reliably suppress the loss of the light H due to the reflection on the incident surface 6a of the translucent substrate 6 and improve the light extraction efficiency. It becomes possible to make it.

  Furthermore, the surface of the second adhesive layer 10 is roughened so that a groove having a width and depth less than the wavelength of the light H generated in the light emitting layer 2 is formed. It is possible to suppress the loss of the light H due to reflection on the surface, and it is possible to improve the light extraction efficiency more reliably.

  Therefore, according to the EL element A of the present embodiment, the scattering prevention sheet 7 according to the present invention not only prevents the scattering of the substrate piece due to the breakage of the translucent substrate 6, but also reduces the loss of the light H. Since the function is provided, the light extraction efficiency of the EL element A can be improved as compared with the conventional EL element 1. Further, since the antireflection layer 8 is provided between the translucent substrate 6 and the anode 3 of the EL element body 5, the loss of the light H can be reduced also by this antireflection layer 8. Thus, the light extraction efficiency of the EL element A can be further improved.

  In addition, when ITO is used for the anode 3 of the EL element A, a film-like transparent base material is used, and continuous production is performed in a roll-to-roll manner, so that the process is simpler than the conventional batch method for each sheet. Therefore, it is possible to improve the process of the EL element A with respect to the anode 3 and, consequently, to improve the cost of the EL element A.

  In addition, since the EL light emitting device such as the illumination device, the display device, and the display device of the present embodiment includes the EL element A having excellent light extraction efficiency as described above, the conventional EL element 1 is used as the light emitting source. As compared with the EL light emitting device provided as the light emitting device, it is possible to improve the light use efficiency (light emitting efficiency) and to improve the performance of the EL light emitting device A such as luminance.

  As described above, the scattering prevention sheet according to the present invention, the EL element including the same, and the EL light emitting device including the EL element as a light source have been described. However, the present invention is limited to the above embodiment. Instead, it can be changed as appropriate without departing from the spirit of the invention.

  Here, the verification test which confirmed the superiority of the scattering prevention sheet 7 of the present invention, the EL element A provided with the same, and the EL light emitting device provided with the EL element A as a light emission source will be described. In this demonstration test, the EL element A of the present invention and the conventional EL elements (Comparative Example 1 and Comparative Example 2) were used to compare the anti-scattering performance and the light emission efficiency (front luminance). The superiority of A (scattering prevention sheet 7 of the present invention, EL light emitting device) was confirmed.

The EL element A of the present invention was formed using a glass plate of 150 mm × 150 mm × 0.7 mm (width × length × thickness) as the transparent substrate 6. Further, an uneven layer 7b having a quadrangular pyramid-shaped recess 11 and a protrusion 12 is integrally laminated on a PET substrate film (transparent substrate 7a) having a thickness of 188 μm using an acrylic ultraviolet curable resin. Thus, the scattering prevention sheet 7 was formed. Moreover, the height of the recessed part 11 and the convex part 12 was 50 micrometers, the pitch was 100 micrometers, and it arranged on the matrix, and formed the scattering prevention sheet 7. FIG. Then, the scattering prevention sheet 7 was laminated on the transparent substrate 6 by pressurizing at 0.2 MPa through the first adhesive layer 9 having a thickness of 25 μm designed to have an adhesive strength of 10 N / inch. Further, TiO ₂ (antireflection film 8b) is formed on a 188 μm thick PET substrate film (transparent substrate 8a) by a sol-gel method to form the antireflection layer 8, and the first adhesive layer 9 and The antireflection layer 8 was laminated on the transparent substrate 6 by applying pressure at 0.2 MPa through the same second adhesive layer 10.

  On the other hand, the EL element of Comparative Example 1 uses a 150 mm × 150 mm × 0.7 mm (width × length × thickness) glass plate as the transparent substrate 6, and a 188 μm thick PET base film (scattering prevention sheet). Was bonded to the transparent substrate 6 via an adhesive layer (first adhesive layer) in the same manner as the EL element A of the present invention.

  The EL element of Comparative Example 2 was formed using a glass plate of 150 mm × 150 mm × 0.7 mm (width × length × thickness) as the transparent substrate 6 without providing a scattering prevention sheet.

  In the anti-scattering performance test, an iron ball having a height of 1 m to 1 kg was dropped on the center of each of the EL element A of the present invention formed as described above, the EL element of Comparative Example 1, and the EL element of Comparative Example 2. The transparent substrate 6 was damaged, and the scattering state of the glass piece (substrate piece) was confirmed. And when a glass piece adheres to the adhesion part (1st adhesion layer) of a scattering prevention sheet and a glass piece does not scatter in the range beyond the area of the transparent substrate 6, (circle) and a glass piece are more than the area of the transparent substrate 6 The case where it scattered in the range of was evaluated as x.

  On the other hand, in the light emission efficiency (front luminance) test, the front luminance of the EL element of Comparative Example 2 without the anti-scattering sheet is set to 1, and the EL element A of the present invention for the EL element of Comparative Example 2 and the EL of Comparative Example 1 are compared. Evaluation was performed by obtaining the luminance ratio of the device and comparing the luminance ratio.

  Table 1 shows the test results of scattering prevention performance and luminous efficiency. From this result, the EL element A of the present invention has excellent scattering prevention performance and can improve the light emission efficiency (light utilization efficiency, light extraction efficiency) as compared with the conventional EL elements (Comparative Examples 1 and 2). Proven to be possible.

DESCRIPTION OF SYMBOLS 1 Conventional EL element 2 Light emitting layer 3 Anode (one electrode layer)
4 Cathode (the other electrode layer)
5 EL element body 6 Translucent substrate 6a One surface (incident surface, incident surface side surface)
6b Other side (outgoing surface, outgoing surface side surface)
7 scattering prevention sheet 7a transparent base material 7b uneven surface 7c surface 8 antireflection layer 8a transparent base material 8b antireflection film 8c surface 9 first adhesive layer 10 second adhesive layer 11 concave portion 12 convex portion A EL element H light T1 lamination Direction T2 Direction along translucent substrate

Claims (7)

A scattering prevention sheet provided to be integrally laminated on the translucent substrate of the EL element, and for preventing the substrate piece from scattering when the translucent substrate is damaged,
The scattering prevention sheet, wherein the surface side is formed with a plurality of concave portions and convex portions arranged geometrically so as to emit light transmitted from the light transmitting substrate side to the outside from the surface. . In the scattering prevention sheet according to claim 1,
The scattering prevention sheet, wherein the plurality of concave portions and / or convex portions are arranged at a constant pitch or randomly in a direction along the translucent substrate. In the scattering prevention sheet according to claim 1 or 2,
The scattering prevention sheet, wherein the plurality of concave portions and / or convex portions are formed in a pyramid shape, a conical shape, a spherical shape, or a combination of two or more of these shapes. A light-transmitting substrate; an EL element body formed by sandwiching a light-emitting layer between a transparent anode and a cathode; and the anode is disposed on one side of the light-transmitting substrate and integrally laminated on the light-transmitting substrate; In an EL device comprising:
The scattering prevention sheet according to any one of claims 1 to 3, which is integrally laminated on the other surface side of the translucent substrate,
An antireflection layer provided between the translucent substrate and the anode of the EL element body;
A first adhesive layer provided between the translucent substrate and the anti-scattering sheet and integrating the translucent substrate and the anti-scattering sheet;
An EL element comprising a second adhesive layer provided between the translucent substrate and the antireflection layer and integrating the translucent substrate and the antireflection layer. . The EL device according to claim 4,
The antireflection layer is formed by forming the antireflection film on the translucent substrate, forming an antireflection film on the anode of the EL element body, or forming the antireflection film on a transparent substrate. ,
An EL element comprising one or multiple layers of the antireflection layer. In the EL device according to claim 4 or 5,
The EL device, wherein the second adhesive layer has a rough surface so that a groove having a width and a depth less than a wavelength of light generated in the light emitting layer is formed. An EL light emitting device including an EL element as a light source,
An EL light-emitting device, wherein the EL element is the EL element according to any one of claims 4 to 6.

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