Transparent light emitting device display

Abstract

A transparent light-emitting device display according to an exemplary embodiment of the present application includes: a transparent substrate; a conductive metal pattern arranged on the transparent substrate; a light-emitting device arranged on at least a portion of the conductive metal pattern; a first transparent adhesive layer arranged on the transparent substrate, the conductive metal pattern and the light-emitting device; an ultraviolet cut-off film arranged on the first transparent adhesive layer; and a second transparent adhesive layer arranged on the ultraviolet cut-off film.

Description

Technical Field

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0035155 filed in the Korean Intellectual Property Office on March 27, 2019, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to a transparent light emitting device display. Background Art

[0003] Recently, South Korea has provided information and attraction to city residents by creating luxurious signboards and various landscape lighting in parks and city centers through the fusion of advanced ICT technology and LED technology. In particular, a transparent LED display using an ITO transparent electrode material is a display in which an LED is applied between glass and glass or a transparent film to which an LED is applied is attached to one surface of glass, and has an advantage that it can be a luxurious appearance because the wires are invisible. Therefore, transparent LED displays have been used indoors in hotels, department stores, etc., and their importance is increasing in realizing media facades on the exterior walls of buildings.

[0004] For transparent electrodes used for touch screens, etc. because the electrodes are transparent and current flows through the electrodes, with the popularity of smart devices, its demand has been surging, and among transparent electrodes, the most frequently used transparent electrode is indium tin oxide (ITO), which is an oxide of indium and tin. However, indium, which is the main raw material of ITO transparent electrode materials, has small reserves in the world and is only produced in some countries such as China, and its production cost is high. In addition, the disadvantage of indium is that the LED light to be displayed is not constant due to the inability to uniformly apply the resistance value. Therefore, there are limitations in using transparent LEDs that use ITO as high-performance, low-cost transparent electrode materials.

[0005] Although it is true that ITO accounts for the largest proportion of transparent electrode materials and has been used as a transparent electrode material, research and technological development using new materials are constantly being carried out due to limitations such as economic feasibility and limited performance. Examples of transparent electrode materials that have attracted attention as next-generation new materials include metal mesh, nanowires (Ag nanowires), carbon nanotubes (CNTs), conductive polymers, graphene, etc. Among them, metal mesh is a new material that accounts for 85% of the materials that replace ITO, and has high conductivity and low cost, and the market is expanding in terms of its application.

[0006] The transparent LED display using the metal mesh is easier to maintain than the existing ITO transparent display, and can not only greatly save resources and significantly improve environmental pollution prevention, but also be economical due to reduced manufacturing costs. In addition, the transparent LED display using the metal mesh can be expanded and applied to various applications, and has the potential to be applied and used as a new transparent electrode material for various products. Summary of the invention

[0007] Technical issues

[0008] The present application is directed to providing a transparent light emitting device display.

[0009] Technical Solution

[0010] An exemplary embodiment of the present application provides a transparent light emitting device display, comprising:

[0011] Transparent substrate;

[0012] A conductive metal pattern disposed on a transparent substrate;

[0013] a light emitting device disposed on at least a portion of the conductive metal pattern;

[0014] a first transparent adhesive layer disposed on the transparent substrate, the conductive metal pattern, and the light emitting device;

[0015] a UV cut-off film disposed on the first transparent adhesive layer; and

[0016] A second transparent adhesive layer is disposed on the UV cutoff film.

[0017] Beneficial Effects

[0018] According to an exemplary embodiment of the present application, a transparent light emitting device display may include an ultraviolet cut-off film, thereby preventing components constituting the transparent light emitting device display from being deteriorated due to ultraviolet rays.

[0019] In addition, according to an exemplary embodiment of the present application, the ultraviolet cut-off film may be included on the first transparent adhesive layer to planarize the structure including the first transparent adhesive layer, and thus, the appearance characteristics of the transparent light emitting device display may be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 and Figure 2 is a diagram schematically illustrating a transparent light emitting device display according to an exemplary embodiment of the present application.

[0021] Figure 3 : is a graph showing optical characteristics of UV cut-off films and general optical films applied in Examples and Comparative Examples according to an exemplary embodiment of the present application.

[0022] Figure 4 is a graph showing light resistance evaluation results of transparent light emitting device displays in Examples 1 to 3 and Comparative Example 1 as an exemplary embodiment of the present application.

[0023] Figure 5 : is a graph showing the light resistance evaluation results of the transparent light emitting device displays in Examples 4 to 6 and Comparative Example 2 as one exemplary embodiment of the present application.

[0024] Description of Reference Numerals

[0025] 10: Transparent base

[0026] 20: Conductive metal pattern

[0027] 30: Light-emitting devices

[0028] 40: First transparent adhesive layer

[0029] 50: UV cut-off film

[0030] 60: Second transparent adhesive layer

[0031] 70: Adhesive layer

[0032] 80: Glass

[0033] 90: Adhesive layer

[0034] 100: Protective film

[0035] 110: Flexible Printed Circuit Board (FPCB) DETAILED DESCRIPTION

[0036] Hereinafter, the present application will be described in detail.

[0037] In the present application, “transparent” is intended to mean having a transmittance characteristic of about 80% or more in the visible light region (400 nm to 700 nm).

[0038] A transparent LED display is a product manufactured by mounting an LED device on a transparent electrode substrate, and is designed to be easily attached to and separated from a glass window by laminating an adhesive layer on the top. In the process of laminating the adhesive layer on the top of the electrode film on which the LED device is mounted, the step difference between the LED device and the electrode film causes the flatness of the adhesive layer surface to decrease, and then distortion of incident light occurs, resulting in degradation of the function of the window. In order to prevent this, a method of laminating a substrate in which a transparent and flat adhesive layer is provided on the top is proposed.

[0039] By attaching a transparent LED display to a glass window forming a building exterior wall to simultaneously function as a luxury display and a transparent window, new value can be given to the existing window. As described above, when a transparent LED display is mounted on a building exterior wall, the product is exposed to natural light for a long time, so the product is required to be durable against ultraviolet rays.

[0040] Polyethylene naphthalate (PEN), which is a transparent LED film substrate in the related art, has a yellowing phenomenon in which the color turns yellow when exposed to ultraviolet rays for a long time, and the laminated transparent LED film may also have a problem of yellowing of the epoxy-based adhesive layer due to ultraviolet rays. As the yellowing occurs more, the transmittance of the product becomes lower, and this phenomenon needs to be alleviated because the product is not good in appearance.

[0041] The present application aims to prevent the yellowing phenomenon that occurs when the material constituting the transparent LED film is exposed to ultraviolet rays for a long time.

[0042] A transparent light-emitting device display according to an exemplary embodiment of the present application includes: a transparent substrate; a conductive metal pattern arranged on the transparent substrate; a light-emitting device arranged on at least a portion of the conductive metal pattern; a first transparent adhesive layer arranged on the transparent substrate, the conductive metal pattern and the light-emitting device; an ultraviolet cut-off film arranged on the first transparent adhesive layer; and a second transparent adhesive layer arranged on the ultraviolet cut-off film.

[0043] In an exemplary embodiment of the present application, the transmittance of the ultraviolet cutoff film in the visible light region (380 nm≤λ≤780 nm) may be 85% or more, and the transmittance in the ultraviolet region (λ<380 nm) may be less than 1%.

[0044] In an exemplary embodiment of the present application, the UV cut-off film may be a transparent film containing a UV absorber. In addition, in another exemplary embodiment of the present application, the UV cut-off film may include: a transparent film; and a UV cut-off coating disposed on the transparent film.

[0045] The transparent film may be composed of: urethane resin; polyimide resin; polyester resin; (meth)acrylate-based polymer resin; polyolefin-based resin such as polyethylene or polypropylene; etc. In addition, the transparent substrate may be a film having a visible light transmittance of 80% or more, such as polyethylene terephthalate (PET), cycloolefin polymer (COP), polyethylene naphthalate (PEN), polyether sulfone (PES), polycarbonate (PC), polymethyl methacrylate (PMMA), and acetyl celluloid.

[0046] More specifically, the transparent film including the ultraviolet absorber may be prepared by using a material obtained by adding the ultraviolet absorber to the above-mentioned transparent film material and subjecting the transparent film material to an extrusion process or the like.

[0047] In addition, the UV cutoff film may be prepared by coating the UV cutoff coating composition on a transparent film.

[0048] The UV cutoff coating composition may include a UV absorber, a photocurable resin, a photoinitiator, and an organic solvent.

[0049] Preferably, the extinction coefficient value of the ultraviolet absorber at a wavelength of 380nm is 0.01 to 0.10. Preferably, the ultraviolet absorber is selected from triazine-based ultraviolet absorbers. Based on 100 parts by weight of the solid content of the coating liquid composition of the coating layer forming the ultraviolet cut-off film, the content of the ultraviolet absorber can be 0.1 parts by weight to 5.0 parts by weight.

[0050] When the content of the ultraviolet absorber is less than 0.1 parts by weight based on 100 parts by weight of the solid content of the coating liquid composition of the coating layer forming the ultraviolet cut-off film, the problem that ultraviolet rays cannot be sufficiently blocked may occur. In addition, when the content of the ultraviolet absorber is greater than 5.0 parts by weight, a large amount of monomolecular ultraviolet absorbers are added to the binder, and as a result, the average molecular weight may be reduced, and thus the durability may be deteriorated, and regarding the compatibility of the resin and the ultraviolet absorber, when the ultraviolet absorber is contained in a large amount, the migration problem of the ultraviolet absorber escaping during the high-temperature drying process after coating is further aggravated, and thus there is a tendency to be unfavorable to processability.

[0051] As the photocurable resin, an acrylic resin can be specifically used, for example, a reactive acrylate oligomer, a multifunctional acrylate monomer or a mixture thereof can be used. As the reactive acrylate oligomer, a urethane acrylate oligomer, an epoxy acrylate oligomer, a polyester acrylate, a polyether acrylate or a mixture thereof can be used. As the multifunctional acrylate monomer, dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, trimethylene propyl triacrylate, propoxylated glycerol triacrylate, trimethylolpropane ethoxy triacrylate, 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, ethylene glycol diacrylate or a mixture thereof can be used.

[0052] Considering imparting appropriate viscosity (to be easy to process when applying UV cut-off coating composition), the film strength of the film finally formed, etc., based on 100 parts by weight of photocurable resin, organic solvent can be preferably 50 parts by weight to 500 parts by weight, more preferably 100 parts by weight to 400 parts by weight, and most preferably 150 parts by weight to 350 parts by weight. In this case, as the type of organic solvent that can be used, one or a mixture of one or more of alcohol, acetate, ketone, cellosolve, dimethylformamide, tetrahydrofuran, propylene glycol monomethyl ether, toluene and dimethylbenzene can be used, but organic solvent is not limited to this. In this case, the example of alcohol includes methanol, ethanol, isopropanol, butanol, isobutanol, diacetone alcohol, etc., but is not limited to this. In addition, as acetate, methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate or cellosolve acetate can be used, and as ketone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone or acetone can be used, but acetate and ketone are not limited to this.

[0053] As the photoinitiator, those known in the art may be used.

[0054] The UV cut-off coating composition may include one or more of a leveling agent, a wetting agent and a defoamer as an additive. Based on 100 parts by weight of the photocurable resin, the additive may be included in an amount in the range of 0.01 parts by weight to 10 parts by weight. The leveling agent is used to make the surface of the coating film applied using the coating composition uniform. In addition, since the wetting agent is used to reduce the surface energy of the coating composition, when the transparent film is applied with the coating composition, the wetting agent helps the coating composition to be applied uniformly. Defoamers may be added to remove bubbles in the coating composition. The solid content of the coating liquid composition forming the coating means components other than the solvent.

[0055] Preferably, the thickness of the UV cutoff coating is 3 μm to 10 μm.

[0056] In addition, preferably, the thickness of the UV cut-off film is 50 μm to 250 μm. When the thickness of the UV cut-off film is less than 50 μm, the processability is poor, and it may be difficult to control the flatness of the adhesive layer by film lamination. In addition, when the thickness of the UV cut-off film is greater than 250 μm, the physical properties of the optical material such as transmittance and haze may deteriorate, which increases the manufacturing cost and is not conducive to reducing the weight of the product.

[0057] In an exemplary embodiment of the present application, an adhesive layer may be further included between the transparent substrate and the conductive metal pattern. That is, the adhesive layer may be disposed on the transparent substrate, and the conductive metal pattern may be disposed on the adhesive layer.

[0058] In addition, in another exemplary embodiment of the present application, a bonding layer may be further included on the transparent substrate, and the conductive metal pattern may be arranged in a form embedded in the bonding layer. In this case, at least a portion of the conductive metal pattern arranged in a form embedded in the bonding layer may be arranged to contact the light-emitting device.

[0059] The adhesive layer may include a thermosetting adhesive composition or a UV-curable adhesive composition, or a cured product thereof.

[0060] The bonding layer may include a thermosetting adhesive composition or an ultraviolet curable adhesive composition, or a cured product thereof. More specifically, the bonding layer may include a silane-modified epoxy resin, a bisphenol A type phenoxy resin, an initiator and a silane coupling agent, but is not limited thereto. The thickness of the bonding layer may be 8 μm to 50 μm. When the bonding layer meets the above thickness range, the metal pattern corresponding to the wiring electrode portion can be completely embedded in the embedding process of the metal pattern set on the bonding layer, and when the thickness of the bonding layer is outside the above thickness range, the wiring electrode portion may not be completely embedded, or the fluidity of the bonding layer may increase, resulting in pattern disconnection. More specifically, when the thickness of the bonding layer is less than 2.5 times the thickness of the metal pattern, it is impossible to completely embed the metal pattern, and therefore the upper surface of the wiring electrode portion is exposed, so that the durability may be deteriorated due to corrosion, and bubbles are trapped in the upper part of the adhesive layer between the wiring electrode portions, so that appearance defects may occur. In addition, when the thickness of the bonding layer is greater than twice the thickness of the metal pattern, the fluidity of the bonding layer may increase during the embedding process by the thermal lamination process, so that the wiring electrode portion pattern may be disconnected.

[0061] In an exemplary embodiment of the present application, the conductive metal pattern may include a wiring electrode part pattern and a light emitting device mounting part pattern, and the light emitting device may be disposed on the light emitting device mounting part pattern.

[0062] In the present application, the wiring electrode portion pattern may include a first common electrode wiring portion pattern, a second common electrode wiring portion pattern and a signal electrode wiring portion pattern. The signal electrode wiring portion pattern may be arranged between the first common electrode wiring portion and the second common electrode wiring portion. In an exemplary embodiment of the present application, the first common electrode wiring portion may be a (+) common electrode wiring portion, and the second common electrode wiring portion may be a (-) common electrode wiring portion. In addition, the first common electrode wiring portion may be a (-) common electrode wiring portion, and the second common electrode wiring portion may be a (+) common electrode wiring portion. According to an exemplary embodiment of the present application, a channel is formed with a structure in which the signal electrode wiring portion passes between the (+) common electrode wiring portion and the (-) common electrode wiring portion, so that the electrode wiring is not separately provided for each light-emitting device, and can be connected as a common electrode between the (+) common electrode wiring portion and the (-) common electrode wiring portion.

[0063] In the present application, the light emitting device mounting part pattern is configured to be provided at a position where the light emitting device is mounted using solder.

[0064] In the present application, the number of light-emitting devices can be appropriately selected by those skilled in the art in consideration of the use of the transparent light-emitting device display, etc., and is not particularly limited. More specifically, the number of light-emitting devices is related to the resistance of the electrode, and when the electrode has a sufficiently low resistance and the area of ​​the display is large, the number of light-emitting devices can be increased. When the number of light-emitting devices is increased in the same area, the resolution is improved, and when the number of light-emitting devices is increased at the same interval, the area of ​​the display is increased and the wires of the power supply unit can be reduced, so the number of light-emitting devices can be appropriately selected by those skilled in the art in consideration of the use of the transparent light-emitting device display, etc.

[0065] In an exemplary embodiment of the present application, the light emitting device may be connected in series with the signal electrode wiring portion pattern and may be connected in series with the first common electrode wiring portion pattern and the second common electrode wiring portion pattern. Since the first common electrode wiring portion pattern and the second common electrode wiring portion pattern provide a sufficient amount of current to drive the light emitting device, and sending a color signal of the light emitting device requires only a small current to send the signal, the first common electrode wiring portion pattern and the second common electrode wiring portion pattern may be connected in series with the signal electrode wiring portion pattern.

[0066] If the light-emitting devices are connected to a power supply unit in parallel with respective electrodes in order to drive all the light-emitting devices and make all the light-emitting devices emit signals instead of having the structure in the present application, the width of each electrode needs to be different (the width of the electrode connected to the farthest light-emitting device is the largest) to satisfy the resistance value depending on the arrangement distance of the light-emitting devices, and due to the spatial limitation of the electrode arrangement area caused by the characteristics of providing a plurality of light-emitting devices, it is difficult to construct an electrode with low resistance.

[0067] In an exemplary embodiment of the present application, the first common electrode wiring portion pattern, the second common electrode wiring portion pattern, and the signal electrode wiring portion pattern may be separated from each other by a disconnection portion. A disconnection portion means an area where a portion of a pattern is cut off to disconnect an electrical connection. The width of the disconnection portion may mean the distance between the nearest ends of the first common electrode wiring portion pattern, the second common electrode wiring portion pattern, and the signal electrode wiring portion pattern that are separated from each other. The width of the disconnection portion may be 80 μm or less, 60 μm or less, 40 μm or less, or 30 μm or less, but is not limited thereto. The width of the disconnection portion may be 5 μm or more. According to an exemplary embodiment of the present application, the identifiability of the wiring may be reduced by minimizing the width of the disconnection portion that separates the first common electrode wiring portion pattern, the second common electrode wiring portion pattern, and the signal electrode wiring portion pattern from each other.

[0068] In an exemplary embodiment of the present application, the line width of the light emitting device mounting part pattern may be 100 μm or more, and may be 100 μm to 1,000 μm, but is not limited thereto.

[0069] In an exemplary embodiment of the present application, the line width of the wiring electrode portion pattern may be 50 μm or less, 30 μm or less, 25 μm or less, or 20 μm or less, but is not limited thereto. The smaller the line width of the wiring electrode portion pattern, the more advantageous the wiring electrode portion pattern is in terms of transmittance and recognizability of wiring, but may result in reduced resistance, in which case the reduction in resistance may be improved when the thickness of the wiring electrode portion pattern increases. The line width of the wiring electrode portion pattern may be 5 μm or more.

[0070] The material of the conductive metal pattern is not particularly limited, but preferably includes one or more of a metal and a metal alloy. The conductive metal pattern may include gold, silver, aluminum, copper, neodymium, molybdenum, nickel or an alloy thereof, but is not limited thereto.

[0071] The thickness of the conductive metal pattern is not particularly limited, but may be 3 μm or more from the viewpoint of conductivity of the conductive metal pattern and economic feasibility of a formation process, and may be 3 μm to 20 μm.

[0072] In an exemplary embodiment of the present application, the first transparent adhesive layer and the second transparent adhesive layer may each independently include one or more of a silicone-based material, an acrylic material, a urethane-based material, and derivatives thereof.

[0073] More specifically, the first transparent adhesive layer can be formed by a composition for an adhesive layer, and the composition for the adhesive layer includes an adhesive resin, such as a (meth) acrylic resin, a carbamate resin, a silicone resin, and an epoxy resin; a curing agent; a photoinitiator; and a silane coupling agent, but the present invention is not limited thereto. For example, a (meth) acrylic resin may include a poly (meth) acrylic acid alkyl ester, and a poly (meth) acrylic acid alkyl ester may include poly methyl acrylate, poly ethyl acrylate, poly propyl acrylate, poly butyl acrylate, poly isopropyl acrylate, poly hexyl acrylate, poly hexyl methacrylate, poly ethyl hexyl acrylate, poly ethyl hexyl methacrylate, and polysiloxane, and is not limited thereto. As a carbamate resin, a polyurethane resin may be used, and the polyurethane resin may include a carbamate group as a non-(meth) acrylic acid ester-based resin without a (meth) acrylic acid ester group. The polyurethane resin may be a commercially available product, or may be synthesized by a typical method.

[0074] The second transparent adhesive layer may include a silicone-based resin and a curing agent. For example, the silicone-based resin may be a polydimethylsiloxane resin containing vinyl. More specifically, the polydimethylsiloxane resin containing vinyl may be prepared from a composition for preparing silicone-based rubber containing vinylmethyldimethoxysilane (which is a silicone monomer containing vinyl) and dimethyldimethoxysilane without vinyl. The composition for preparing silicone-based rubber may also include other typical silicone monomers other than dimethyldimethoxysilane as silicone monomers without vinyl. The curing agent may include a silicone-based compound having two or more Si-H groups to react with the curable functional groups of the silicone-based rubber by hydrosilylation. The curing agent may react by hydrosilylation by heat and / or ultraviolet. Based on 100 parts by weight of silicone-based rubber, the curing agent may be included in an amount of 0.1 to 20 parts by weight, specifically 0.5 to 18 parts by weight, and specifically 0.7 to 15 parts by weight. In the above range, the effect of the degree of curing capable of exhibiting an impact resistance effect can be achieved.

[0075] The first transparent adhesive layer is formed to have a thickness of 1.0 mm to 10.0 mm thicker than the height step difference of the light emitting device, but is not limited to this thickness. When the thickness of the first transparent adhesive layer is formed to be less than 1.0 mm thicker than the height step difference of the light emitting device, the surface of the light emitting device mounted on the top of the electrode film cannot be fully covered, so the light emitting device may be damaged when external impact occurs, and the adhesive properties of the ultraviolet cutoff film laminated on the first transparent adhesive layer may be deteriorated. In addition, when the thickness of the first transparent adhesive layer is formed to be greater than 10.0 mm than the height step difference of the light emitting device, unnecessary material consumption occurs, which may be detrimental to weight reduction of the product.

[0076] The thickness of the second transparent adhesive layer may be 0.01 mm to 10.0 mm, but is not limited thereto. When the thickness of the second transparent adhesive layer is less than 0.01 mm, the leveling property of the second transparent adhesive layer formed by the liquid silicone resin deteriorates, the uniformity of the thickness of the second transparent adhesive layer may be impaired, and there are problems with durability against physical damage that may occur during the operation of repeatedly attaching and detaching the product, which is not preferred. In addition, when the thickness of the second transparent adhesive layer is greater than 10.0 mm, unnecessary material consumption occurs, which may be detrimental to weight reduction of the product.

[0077] In an exemplary embodiment of the present application, the transparent substrate may be a glass substrate or a transparent plastic substrate having excellent transparency, surface smoothness, ease of handling, and waterproof properties, but is not limited thereto, and there is no limitation as long as the transparent substrate is a transparent substrate commonly used for electronic devices. Specifically, the transparent substrate may be composed of: glass; urethane resin; polyimide resin; polyester resin; (meth) acrylate-based polymer resin; polyolefin-based resins such as polyethylene or polypropylene; and the like. In addition, the transparent substrate may be a film having a visible light transmittance of 80% or more, such as polyethylene terephthalate (PET), cycloolefin polymer (COP), polyethylene naphthalate (PEN), polyether sulfone (PES), polycarbonate (PC), and acetyl celluloid. The thickness of the transparent substrate may be 25 μm to 250 μm, but is not limited thereto.

[0078] The transparent light emitting device display according to an exemplary embodiment of the present application is as follows Figure 1 and Figure 2 More specifically, the following Figure 1 A transparent light emitting device display including a bonding layer between a transparent substrate and a conductive metal pattern is shown, and the following Figure 2 A transparent light emitting device display including an adhesive layer on a transparent substrate is shown, wherein a conductive metal pattern is provided in the form of being embedded in the adhesive layer.

[0079] Embodiments of the invention

[0080] Hereinafter, exemplary embodiments described in this specification will be illustrated by examples. However, the scope of the exemplary embodiments is not intended to be limited by the following examples.

[0081] <Example>

[0082] <Example 1>

[0083] The raw material used in this application was prepared by electroplating on polyethylene terephthalate (PET, XG7PH2 manufactured by Toray Industries Inc.) to form a copper (Cu) layer, and a dry film resist (DFR, Asahi Chemical Industry SPG-152) was thermally laminated on the metal surface at 100°C using a roll laminator.

[0084] A photomask including a wiring electrode portion pattern and a light emitting device mounting portion pattern was applied to the upper surface of the Cu plating raw material in which the DFR was laminated, and a collimated exposure device was used at 250 mJ / cm 2 The light intensity is 365nm and it is exposed to ultraviolet light with a wavelength of 365nm. After that, a metal pattern with an uneven structure is formed on the top of the bonding layer by a wet process of development-etching-stripping. All solutions used in each step are kept at room temperature. A 1.0 wt% Na2CO3 aqueous solution is used as a developing solution, an etchant is a mixed solution comprising ferric chloride and hydrochloric acid, and a 2.0 wt% NaOH aqueous solution is used as a stripping solution.

[0085] The Cu wiring electrode portion pattern was a repeated square grid pattern, which was identical, and had a line width of 24 μm, a pitch of 300 μm, a line height of 8 μm, and a disconnection portion with a width of 60 μm.

[0086] After solder paste is screen-printed on the electrode pad portion, the light emitting device is mounted and introduced at a temperature of about 170°C, and the light emitting device mounting portion and the light emitting device are bonded by a solder paste reflow process using solder paste. In order to form a first adhesive layer on top of the light emitting device and the electrode film, a 1 cm per unit area 2The first adhesive layer composition is applied to the electrode film in an amount of 1g or less. After the adhesive layer is left to stand at room temperature for 10 minutes or more to achieve the flattening of the adhesive layer by leveling, when the bonding strength relative to glass is 100gf / inch or more, a laminator is used to laminate the UV cut-off film on the adhesive layer. The UV cut-off film is manufactured by coating an optical PET film (V5400 manufactured by SKC) with a thickness of 188μm with a composition containing 1.0 parts by weight of an ultraviolet absorber and drying the optical PET film at 100°C for 10 minutes. The composition for forming the second adhesive layer is applied to the top of the UV cut-off film and left to stand at room temperature for 48 hours.

[0087] Both surfaces of the UV cutoff film were coated with DY-39-067 (Dow Chemical) to improve adhesion to the silicone adhesive and left to stand at room temperature for 90 minutes. The composition for the first adhesive layer and the composition for the second adhesive layer were prepared as follows: 50 parts by weight of methyl ethyl ketone were added to 10 parts by weight of Sylgard 184B (Dow Chemical, solid content; 100 wt%) containing a curing agent in 100 parts by weight of Sylgard 184A (Dow Chemical, solid content: 100 wt%) containing a vinyl-containing polydimethylsiloxane resin, and the resulting mixture was stirred.

[0088] <Example 2>

[0089] The process was performed in the same manner as in Example 1, except that a PMMA film coated with a composition including 2.0 parts by weight of an ultraviolet absorber was used as the ultraviolet cutoff film laminated on top of the first adhesive layer in Example 1.

[0090] <Example 3>

[0091] The process was performed in the same manner as in Example 1, except that a PET film coated with a composition including 2.0 parts by weight of an ultraviolet absorber was used as an ultraviolet cutoff film laminated on top of the first adhesive layer in Example 1.

[0092] <Comparative Example 1>

[0093] The process was performed in the same manner as in Example 1, except that an optical PET film (V5400 manufactured by SKC) having a thickness of 188 μm was laminated on top of the first adhesive layer in Example 1.

[0094] <Example 4>

[0095] The process was performed in the same manner as in Example 1 except that a copper foil laminate film was used instead of the Cu plated film as a raw material for the electrode film in Example 1.

[0096] The copper foil laminated film is generally a copper film having the same structure as the well-known Cu-clad laminate (CCL), and is prepared by forming an adhesive layer on a transparent substrate and then thermally laminating with copper foil. The coating solution for the adhesive layer is prepared by introducing a silane-modified epoxy resin, a bisphenol A epoxy resin and a phenoxy resin in a weight ratio of 35:33:30 and diluting the resulting mixture with methyl ethyl ketone (MEK). The prepared solution is comma-coated on a PET film having a thickness of 100 μm and subjected to a high temperature drying process at 130 ° C for 3 minutes to form a 25 μm thick adhesive layer. The copper foil laminated film is prepared by subjecting a copper foil (LPF manufactured by ILJIN MATERIALS CO., LTD.) having a thickness of 8 μm and an adhesive layer to roller lamination at a temperature of 100 ° C. A dry film resist was thermally laminated on top of the copper foil of the manufactured copper foil laminate film at a temperature of 100° C. and exposed at 250 mJ / cm using a collimated exposure device and a negative photomask corresponding to the first metal foil pattern and the second metal foil pattern. 2 The light intensity was exposed to ultraviolet light with a wavelength of 365nm. A metal pattern with an uneven structure was formed on the top of the bonding layer by a wet process of development-etching-stripping. All solutions used in each step were kept at room temperature. A 1.0 wt% Na2CO3 aqueous solution was used as a developing solution, an etchant was a mixed solution containing ferric chloride and hydrochloric acid, and a stripping solution was a 2.0 wt% NaOH aqueous solution. In order to flatten the surface of the bonding layer and embed the metal pattern into the bonding layer, a roll laminator was used at 100°C to thermally laminate the metal pattern film and a release PET film with a thickness of 50μm (SLF050-060 manufactured by OPTIVER Korea). UV curing was performed in a state laminated with a release film, and ultraviolet light with a wavelength of 365nm was used at 5,000mJ / cm 2 The light intensity irradiates the surface of the PET film.

[0097] <Example 5>

[0098] The process was performed in the same manner as in Example 4, except that a PMMA film coated with a composition including 2.0 parts by weight of an ultraviolet absorber was used as the ultraviolet cutoff film laminated on top of the first adhesive layer in Example 4.

[0099] <Example 6>

[0100] The process was performed in the same manner as in Example 4, except that a PET film coated with a composition including 2.0 parts by weight of an ultraviolet absorber was used as the ultraviolet cutoff film laminated on top of the first adhesive layer in Example 4.

[0101] <Comparative Example 2>

[0102] The process was performed in the same manner as in Example 4, except that an optical PET film (V5400 manufactured by SKC) having a thickness of 188 μm was laminated on top of the first adhesive layer in Example 4.

[0103] <Experimental Example 1>

[0104] The optical properties of the UV cut-off films used in Examples 1 to 6 and the general optical PET films used in Comparative Examples 1 and 2 were evaluated and are shown in Tables 1 and 2 below. Figure 3 Optical properties were measured using a Solid spec-3700 device.

[0105] [Table 1]

[0106]

[0107] As a result of measuring optical characteristics, it was confirmed that the higher the weight part of the ultraviolet absorber in the ultraviolet cut-off coating liquid composition, the lower the transmittance in the UVA region became, and the b* and YI values ​​decreased regardless of the coating substrate.

[0108] <Experimental Example 2>

[0109] The change in yellowness index of the transparent light emitting device displays prepared in Examples 1 to 6 and Comparative Examples 1 and 2 according to the light resistance evaluation time was evaluated, and the results are shown in the following Tables 2 and Figure 4 and Figure 5 middle.

[0110] Light fastness evaluation device: QUV manufactured by Q-LAB Co., Ltd. (light intensity: 750 mW / m 2 )

[0111] Optical property measurement apparatus: COH-400 (manufactured by Nippon Denshoku Industries Co., Ltd.)

[0112] [Table 2]

[0113]

[0114] As shown in the results, it can be determined that the lower the transmittance of the UVA region of the UV cutoff film, the smaller the yellowing of the product caused by UV exposure. In particular, since the adhesive layer used in the embedded electrode film is severely yellowed by UV, the anti-yellowing effect is greater than that of the protruding electrode film.

[0115] As shown in the results, according to an exemplary embodiment of the present application, the transparent light-emitting device display may include an ultraviolet cut-off film, thereby preventing the components constituting the transparent light-emitting device display from being degraded due to ultraviolet rays. In addition, according to an exemplary embodiment of the present application, the ultraviolet cut-off film may be included on the first transparent adhesive layer, thereby flattening the structure including the first transparent adhesive layer, and thus, the appearance characteristics of the transparent light-emitting device display may be ensured.

Claims

1. A transparent light emitting device display, comprising: Transparent substrate; A conductive metal pattern disposed on the transparent substrate; a light emitting device disposed on at least a portion of the conductive metal pattern; a first transparent adhesive layer disposed on the transparent substrate, the conductive metal pattern, and the light emitting device; a UV cutoff film disposed directly on the first transparent adhesive layer; and a second transparent adhesive layer disposed directly on the UV cutoff film, wherein the transparent light emitting device display further comprises an adhesive layer directly disposed on the transparent substrate, and the conductive metal pattern is embedded in the adhesive layer, and wherein the bonding layer is in contact with the first transparent adhesive layer, wherein the adhesive layer comprises a thermosetting adhesive composition or an ultraviolet curable adhesive composition, or a cured product thereof, wherein the first transparent adhesive layer and the second transparent adhesive layer each independently comprise one or more of a silicone-based material, an acrylic material, and a urethane-based material, The UV cut-off film comprises a transparent film and a UV cut-off coating disposed on the transparent film, wherein the content of the UV absorber is 2.0 to 5.0 parts by weight based on 100 parts by weight of the solid content of the coating liquid composition of the UV cut-off coating forming the UV cut-off film, wherein the UV absorber is a triazine-based UV absorber.

2. The transparent light emitting device display according to claim 1, wherein the transmittance of the ultraviolet cut-off film in the visible light region of 380 nm ≤ λ ≤ 780 nm is 85% or more, and The transmittance in the ultraviolet region of λ<380 nm is less than 1%. 3 . The transparent light emitting device display according to claim 1 , wherein at least a portion of the conductive metal pattern embedded in the adhesive layer is disposed such that the portion of the conductive metal pattern contacts the light emitting device.

4. The transparent light emitting device display according to claim 1, wherein the conductive metal pattern includes a wiring electrode portion pattern and a light emitting device mounting portion pattern, and The light emitting device is disposed on the light emitting device mounting part pattern.

5. The transparent light emitting device display according to claim 4, wherein the line width of the wiring electrode portion pattern is 50 μm or less, and The light emitting device mounting part pattern has a line width of 100 μm or more. 6 . The transparent light emitting device display according to claim 1 , wherein the conductive metal pattern comprises gold, silver, aluminum, copper, neodymium, molybdenum, nickel or an alloy thereof. 7 . The transparent light emitting device display according to claim 1 , wherein the thickness of the conductive metal pattern is 3 μm to 20 μm.

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