KR101749358B1 - Composition of enhanced-reflex transparent film, light-emitting element, and method of producing light-emitting element - Google Patents

Abstract

And aims at enhancing the light emitting efficiency of the light emitting element by increasing the reflectance of the reflective film reflecting the light emitted from the light emitting element. It is another object of the present invention to provide a light emitting device which is improved in reflectivity of the reflective film by using a wet coating method and which is manufactured at a low cost by a simple manufacturing process. A light-emitting layer 40, a light-transmitting substrate 30, an increase / decrease transparent film 20, and a reflection film 10 for reflecting light emitted from the light-emitting layer in this order A composition for a reflectively reflective transparent film (20) for a light emitting device, characterized in that the composition for the reflectively reflective transparent film (20) contains a translucent binder.

Description

TECHNICAL FIELD [0001] The present invention relates to a composition for a reflectively reflective film, a light-emitting device, and a method for manufacturing a light-

TECHNICAL FIELD The present invention relates to a composition for a retroreflective film for a light emitting device, a light emitting device manufactured by the composition for a reflective and transparent film for a light emitting device, and a method of manufacturing the light emitting device. More particularly, the present invention relates to a light-emitting device having a light-emitting layer, a light-transmitting substrate, an anti-reflective and transparent film, and a reflective and reflective transparent film for efficiently reflecting light emitted from the light- And a manufacturing method thereof.

2. Description of the Related Art In recent years, LED light sources, among others, have been used in various fields accompanying high brightness. Particularly, since a white LED light source can be realized, it is used in applications such as a lighting apparatus and a backlight of a liquid crystal display.

In order to further increase the brightness and the like of the LED light source, it has been studied to utilize the light emission from the LED element efficiently. The LED includes a substrate, an LED element mounted on the support substrate, and an encapsulant containing the fluorescent agent, An LED light source having an Ag-plated electrode film for reflecting the light emitted from the LED element and having a titanium thin film on the Ag-plated electrode film is disclosed between the LED elements (Patent Document 1).

The LED light source effectively reflects light from the light emitting body and increases the light emission intensity by forming a reflective film layer between the substrate and the LED element. Here, the Ag thin film and the titanium thin film are formed by a plating method or a vacuum film forming method.

In general, the plating method is expected to generate troublesome processes and waste liquids, and the vacuum film forming method requires a large cost for maintaining and operating a large-sized vacuum film forming apparatus. The LED light source requires a titanium thin film because heat deterioration or light deterioration occurs only with an Ag-plated electrode film, and it is necessary to use a plating method and a vacuum film forming method in combination.

Also disclosed is a method of manufacturing an LED device in which an LED element is mounted on a substrate, wire-bonded, and then an SiO ₂ coating film is formed (Patent Document 2).

However, in the manufacturing method of the LED device, a silver plating film is used. In addition, since the SiO ₂ coating film is formed after the LED element is mounted, there is a problem that the yield of the LED element is deteriorated when the SiO ₂ coating solution is applied. Further, since the SiO ₂ coating film is formed after wire bonding, there is also a problem that the wire is collapsed.

The present invention is directed to a light emitting device having a light emitting layer, a light transmitting substrate, and a reflecting film for reflecting light emitted from the light emitting layer in this order. In this light emitting device, there is no reflective film between the light emitting layer and the transparent substrate, and thermal deterioration or light deterioration occurs only with the Ag-plated electrode film. Therefore, a titanium thin film is required for the light emitting element. For the reasons described above, it is necessary to use a plating method and a vacuum film forming method in combination to manufacture this light emitting element.

Japanese Laid-Open Patent Publication No. 2009-231568 Japanese Patent Application Laid-Open No. 2009-224536

The present invention has been made to solve the above problems. An object of the present invention is to improve the light emitting efficiency of a light emitting device by improving the reflectance of a reflective film for reflecting light emitted from the light emitting device. It is another object of the present invention to provide a light emitting device which is improved in reflectivity of the reflective film by using a wet coating method and which is manufactured at a low cost by a simple manufacturing process.

The composition for a thick-and-reflect reflective film for a light-emitting element of the first aspect of the present invention and the constitution of the light-emitting element of the second aspect of the present invention are shown below.

(1) A composition for an antiglare-reflective film for a light-emitting device, comprising a light-emitting layer, a light-transmitting substrate, an antiglare-reflective transparent film, and a reflective film for reflecting light emitted from the light- By weight based on the total weight of the composition.

(2) The composition for a light-and-reflective transparent film for a light-emitting element according to (1), further comprising a transparent particle.

(3) The composition for a photothermographic reflective film for a light-emitting device according to (1) or (2), wherein the light-transmitting binder is a polymeric binder which is cured by heating.

(4) The composition for a reflective / reflective film for a light-emitting device according to (1) or (2), wherein the translucent binder is a non-polymeric binder which is cured by heating.

(5) The composition for a reflective / reflective film for a light-emitting device according to (1) or (2), wherein the light-transmitting binder is a mixture of a polymeric binder and a non-polymeric binder curable by heating.

(6) The toner according to the above item (1), wherein the polymer type binder is selected from acrylic resin, polycarbonate, polyester, alkyd resin, polyurethane, acrylic urethane, polystyrene, polyacetal, polyamide, polyvinyl alcohol, polyvinyl acetate, cellulose and siloxane polymer (3) or (5), wherein the composition is one or two or more selected from the group consisting of the following.

(7) The non-polymeric binder according to any one of (1) to (7), wherein the non-polymeric binder is selected from the group consisting of metal soaps, metal complexes, metal alkoxides, hydrolysates of metal alkoxides, alkoxysilanes, halosilanes, (3) or (5), wherein the composition is at least two kinds.

(8) The composition for a light-and-reflective element for a light-emitting device according to (2), wherein the transparent particles are oxide fine particles.

(9) The composition for a reflective / reflective film for a light-emitting device according to (2), wherein the transparent particles are transparent conductive oxide particles.

(10) The transparent conductive oxide particle according to the above item (9), wherein the transparent conductive oxide particle contains one or more selected from the group consisting of a powder of indium tin oxide, a powder of antimony doped tin oxide, (EN) COMPOSITION FOR SYMPTOMETRIC SHIELDING FILM FOR LIQUID DEVICE

(11) The composition for a reflective / reflective film for a light emitting device according to (9), wherein the average particle diameter of the transparent conductive particles is within a range of 10 to 100 nm.

(12) The composition for a reflectively reflective transparent film for a light-emitting device according to (1) or (2), wherein the composition for a reflectively reflective film comprises a composition for a high refractive index retroreflective film and a composition for a low refractive index retroreflective film.

(13) A light-emitting element comprising a light-emitting layer, a light-transmitting substrate, a reflectively reflective transparent film, and a reflective film for reflecting light emitted from the light-emitting layer in this order, wherein the reflectively reflective transparent film contains a transparent binder .

(14) The light emitting device according to (13), wherein the reflectively reflective transparent film has two layers and the refractive index of the reflectively reflective transparent film on the transparent substrate side is lower than the refractive index of the reflectively reflective transparent film on the reflective film side.

(15) The light emitting device according to (13), wherein the reflective film further comprises a protective film containing a binder on the opposite surface of the reflectively reflective transparent film.

(16) The light-emitting device according to any one of (13) to (15), wherein the reflectively reflecting transparent film and / or the reflective film is produced by a wet coating method.

A configuration of a method for manufacturing a light emitting device according to a third aspect of the present invention will be described below.

(17) A method for producing a transparent conductive film, comprising the steps of applying a composition for an anti-reflective and transparent film containing a translucent binder on a translucent substrate by a wet coating method and then baking or curing it to form an anti-reflective transparent film, And a composition for a reflective film containing an additive are applied by a wet coating method and then baked or cured to form a reflective film and a light emitting layer is formed on the opposite surface of the reflective film of the transparent substrate.

(18) A method for forming a protective film by forming a protective film by applying a protective film composition containing a binder by a wet coating method on a reflective film, followed by baking or curing, 17). ≪ / RTI >

According to the composition for a reflectively reflective film of the first aspect of the present invention, the reflectance of a reflective film that reflects light emitted from the light-emitting device can be increased to improve the luminous efficiency of the light-emitting device. This reflective film can be used for various light sources, and is particularly suitable for an LED light source. In addition, since the composition for a reflective / transparent film of the first aspect of the present invention can be wet-coated, the luminous efficiency of the light emitting device can be increased at low cost by a simple manufacturing process.

According to the light emitting element of the second aspect of the present invention, a light emitting element having high light emitting efficiency can be provided.

According to the method for manufacturing a light emitting element of the third aspect of the present invention, a light emitting element having a high light emitting efficiency can be obtained easily at low cost.

1 is a cross-sectional view showing an example of a light emitting device of the present invention.
2 is a cross-sectional view showing a preferred example of the light emitting device of the present invention.
3 is a cross-sectional view showing a more preferable example of the light emitting device of the present invention.

Hereinafter, the present invention will be described in detail based on embodiments. In addition, unless otherwise indicated,% is% by mass except for numerical values.

[Composition for a reflective / reflective film for a reflective film for a light emitting device]

(Hereinafter referred to as a composition for an anti-reflective film for a light-emitting element) of the first aspect of the present invention (hereinafter referred to as a composition for an anti-reflective coating of the present invention) comprises a light-emitting layer, a transparent substrate, Wherein the composition for an anti-reflection film for a light-emitting element comprises a transparent binder.

By using the composition for a reflectively reflective film of the present invention as a material, an evaporation-reflective transparent film containing a light-transmitting binder can be formed between the light-transmitting substrate and the reflective film. It is also possible to use a two-layer antireflection transparent film by preparing two compositions of a composition for a reflectively reflective film and a composition for a high refractive index retroreflective film and a composition for a low refractive index retroreflective film, It is possible to manufacture an azeotropic transparent film having a refractive index lower than the refractive index of the reflectively reflective transparent film on the reflective film side. A light emitting element having a light emitting layer, a reflecting film for reflecting light emitted from the light emitting layer, and a light transmitting substrate in this order will be described later.

As the translucent binder, there can be used a polymer type binder which is cured by heating, a non-polymer type binder which is cured by heating, or a mixture thereof. Use of a binder that is cured by heating is preferable from the viewpoint of adhesion because curing after coating is easy.

Examples of the polymer type binder include acrylic resin, polycarbonate, polyester, alkyd resin, polyurethane, acrylic urethane, polystyrene, polyacetal, polyamide, polyvinyl alcohol, polyvinyl acetate, cellulose, siloxane polymer, Can be used. The polymer type binder may be selected from the group consisting of metal soaps of metal such as aluminum, silicon, titanium, chromium, manganese, iron, cobalt, nickel, silver, copper, zinc, molybdenum and tin, metal complexes, metal alkoxides and hydrolyzates of metal alkoxides It is preferable to contain at least one kind selected.

Examples of non-polymer type binders include metal soaps, metal complexes, metal alkoxides, hydrolyzates of metal alkoxides, alkoxysilanes, halosilanes, 2-alkoxyethanol, beta -diketone, alkyl acetates and mixtures thereof . The metal contained in the metal soap, the metal complex or the metal alkoxide is preferably aluminum, silicon, titanium, chromium, manganese, iron, cobalt, nickel, silver, copper, zinc, molybdenum, tin, indium or antimony. It is more preferable that the non-polymer type binder is silicon, an alkoxide of titanium (for example, tetraethoxysilane, tetramethoxysilane, butoxysilane). As halosilanes, trichlorosilane can be used. By polymerizing these polymer type binders and non-polymer type binders by heating, it becomes possible to form an ITO film having high adhesiveness.

When the metal alkoxide is cured, an alkali such as hydrochloric acid, nitric acid, phosphoric acid (H ₃ PO ₄ ), an acid such as sulfuric acid, or ammonia water or sodium hydroxide is contained as a catalyst together with moisture for initiating the hydrolysis reaction desirable. Among the above-mentioned compounds, nitric acid is particularly preferable. When nitric acid is used as the catalyst, the catalyst is liable to volatilize after heat curing and does not remain well. In addition, halogen does not remain. In addition, P, which is weak in water resistance, does not remain. In addition, adhesion after curing is excellent.

When the composition for a reflectively reflective film of the present invention contains transparent particles, it is preferable because the refractive index of the reflectively-reflective transparent film can be controlled. The refractive index of the transparent particles will be described later. The transparent particles are preferably oxide fine particles from the viewpoint of light transmittance, stability, and weather resistance. When conductivity is required for the reflectively reflective transparent film, it is preferable to use transparent conductive particles. Examples of transparent conductive oxide particles include tin oxide powder of indium tin oxide (ITO), tin oxide powder of ATO (antimony tin oxide), and tin oxide powder of Al, Co, Fe, In, Sn and Ti And zinc oxide powder containing at least one kind of metal selected from the group consisting of zinc oxide and zinc oxide. Of these, ITO, ATO, AZO (Aluminum Zinc Oxide), IZO (Indium Zinc Oxide) and TZO (Tin Zinc Oxide) are more preferable. The average particle diameter of the transparent conductive particles is preferably in the range of 10 to 100 nm, more preferably in the range of 20 to 60 nm, in order to maintain stability in the dispersion medium. Here, the average particle size is measured by the BET method by the specific surface measurement by QUANTACHROME AUTOSORB-1 or the dynamic light scattering method by LB-550 manufactured by Horiba Manufacturing Co. Hereinafter, unless otherwise specified, the average particle size is measured using the BET method by non-surface measurement by QUANTACHROME AUTOSORB-1. The shape of the transparent conductive particle is preferable in terms of spherical shape, needle-like shape, dispersibility, and conductivity.

For the light-transmitting binder, it is preferable to add a coupling agent depending on other components to be used. This is because, by adding the coupling agent to the light-transmitting binder, the adhesion between the transparent substrate and the reflectively-reflecting transparent film and the adhesion between the reflectively-reflective transparent film and the reflective film are improved, and the adhesion between the transparent particle and the transparent binder is also improved. As the coupling agent, a silane coupling agent, an aluminum coupling agent, a titanium coupling agent, or the like can be used.

It is preferable that the composition for the reflectively reflective film contains a dispersion medium in order to improve film-forming properties of the reflectively-reflective transparent film. The dispersion medium may be a solvent which is compatible with 1% by mass or more, preferably 2% by mass or more of water and 2% by mass or more, and preferably 3% by mass or more of water with respect to 100% by mass of all the dispersion medium, It is preferable to contain alcohols. For example, when the dispersion medium comprises only water and an alcohol, 98% by mass of the alcohol is contained when 2% by mass of water is contained, and 98% by mass of water is contained when 2% by mass of the alcohol is contained. The protective molecule chemically modified on the surface of the dispersion medium, that is, the metal nanoparticle, contains either or both of a hydroxyl group (-OH) and a carbonyl group (-C═O). The content of water is preferably 1% by mass or more based on 100% by mass of all the dispersion medium. This is because when the content of water is less than 2% by mass, it becomes difficult to sinter the film obtained by applying the composition for a reflective film by a wet coating method at a low temperature. In addition, the reflectance of the reflective film after baking also decreases. When the hydroxyl group (-OH) is contained in a protective agent chemically modifying metal nanoparticles such as silver nanoparticles, the dispersion stability of the composition for a reflective film is improved, so that the low temperature sintering of the coating film is facilitated. When the carbonyl group (-C = O) is contained in a protective agent for chemically modifying metal nanoparticles such as silver nanoparticles, the dispersion stability of the composition for a reflective film is improved similarly to the above, so that the low temperature sintering of the coating film is facilitated. As the solvent compatible with water used in the dispersion medium, alcohols are preferable. Among these, the alcohols include one or more selected from the group consisting of methanol, ethanol, propanol, butanol, ethylene glycol, propylene glycol, diethylene glycol, glycerol, isobornylhexanol and erythritol .

The content of the light-transmitting binder is preferably 10 to 90 parts by mass, more preferably 30 to 80 parts by mass, per 100 parts by mass of the composition for a reflectively reflective film except for the dispersion medium. When the amount is 10 parts by mass or more, the adhesive strength with the light-transmitting substrate or the reflective film is good, and when it is 90 parts by mass or less, film unevenness during film formation hardly occurs. In the case of using metal alkoxide as a binder and nitric acid as a catalyst, 1 to 10 parts by mass of nitric acid per 100 parts by mass of the metal alkoxide is preferable in view of the curing rate of the binder and the amount of residual nitric acid.

The amount of the transparent particles is preferably 10 to 90 parts by mass, more preferably 20 to 70 parts by mass, relative to 100 parts by mass of the composition for a reflectively reflective film except for the dispersion medium. If it is 10 parts by mass or more, the effect of returning the returned light from the reflectively reflective transparent film to the reflective film side can be expected. If the amount is 90 parts by mass or less, the intensity of the reflectively reflected transparent film itself, Adhesive strength is maintained.

The dispersion medium is preferably 50 to 99 parts by mass based on 100 parts by mass of the composition for a reflectively reflective film, from the viewpoint of coating ability.

When a coupling agent is used, the amount is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 2 parts by mass based on 100 parts by mass of the composition for a reflectively reflective film except for the dispersion medium. When the amount is more than 0.01 part by mass, the adhesion to the reflective film or the sealing material film can be improved and the effect of improving the dispersibility of the particles can be remarkably improved. If more than 5 parts by mass, film unevenness is likely to occur.

It is preferable to add a low-resistance agent or a water-soluble cellulose derivative to the composition for an anti-reflective film according to the component to be used. The low resistance agent and the water-soluble cellulose derivative are also the same as the composition for a reflective film.

The composition for a reflectively reflective film may further contain an antioxidant, a leveling agent, a thixotropic agent, a filler, a stress relieving agent, and other additives as needed insofar as the object of the present invention is not impaired.

[Composition for a high refractive index reflective and transparent film]

The above-described composition for an ITO film can be used for the composition for a high refractive index retroreflective film. Hereinafter, a method for producing a composition for an ITO film having a higher refractive index will be described.

The composition for a high refractive index retroreflective film contains the above-mentioned light transmitting binder, and the transparent conductive particles, SiO ₂ (Refractive index: 1.54), TiO ₂ (refractive index: 2.7), ZrO ₂ (refractive index: 2) and diamond (refractive index: 2.4) The refractive index of the transparent conductive particles is about 2 for all of the ITO, ATO and zinc oxide containing at least one kind of metal selected from the group consisting of Al, Co, Fe, In, Sn and Ti, Is about 1.3 to 1.6.

The transparent conductive particles are preferably 10 to 90 parts by mass, more preferably 20 to 70 parts by mass, per 100 parts by mass of the composition for a high refractive index retentive reflective film except for the dispersion medium. If it is 10 parts by mass or more, the effect of returning the returned light from the reflectively reflective transparent film to the reflectively reflective transparent film side can be expected. If the amount is 90 parts by mass or less, the strength of the reflectively reflective transparent film itself, The adhesive force to the reflective transparent film or the sealing material film is maintained.

From the viewpoint of adjusting the refractive index, the transparent particles are preferably 10 to 80 parts by mass from the viewpoint of adjusting the refractive index, with respect to 100 parts by mass of the composition for a high refractive index retroreflective film excluding the dispersion medium.

The content of the light-transmitting binder is preferably 10 to 90 parts by mass, more preferably 30 to 80 parts by mass, per 100 parts by mass of the composition for a high refractive index retentive reflective film except for the dispersion medium. If the amount is 10 parts by mass or more, the adhesive strength with the reflectively-reflecting transparent film is good, and if it is 90 parts by mass or less, film unevenness at the time of film formation is hardly generated.

[Composition for low reflectance increase reflective film]

The composition for a low refractive index retroreflective film is a composition comprising a transparent translucent binder and transparent conductive particles and further comprising silsesquioxane particles (refractive index: 1.15 to 1.45) and magnesium fluoride particles (refractive index: 1.18 to 1.38) At least one kind of transparent particles selected from the group consisting of The average particle diameter of the low refractive transparent particles is preferably 1 to 50 nm.

The composition for a low refractive index retroreflective film contains 98 to 65 parts by mass, preferably 95 to 70 parts by mass, of conductive oxide particles per 100 parts by mass of the total of the conductive oxide particles and the low refractive index transparent particles. When the upper limit value is exceeded, the adhesiveness is lowered, and when it is lower than the lower limit value, the conductivity is lowered.

Refractive-index transparent particles are contained in an amount of 2 to 35 parts by mass, preferably 5 to 30 parts by mass, per 100 parts by mass of the total of the conductive oxide particles and the low refractive refractive-index transparent particles. Below the lower limit value, the refractive index of the after-curing highly reflective transparent film can not be sufficiently lowered, and the conductivity is lowered above the upper limit value.

The content of the light-transmitting binder is preferably from 5 to 50 parts by mass, more preferably from 10 to 30 parts by mass, per 100 parts by mass of the composition for a low refractive index retroreflective film except for the dispersion medium.

Further, either one of the composition for a high refractive index retentive reflective film and the composition for a low refractive index retentive reflective film may be used as the above-mentioned composition for an anti-reflective film.

[Composition for a reflective film for a light emitting device]

A composition for a reflective film for a light emitting element (hereinafter referred to as a composition for a reflective film) contains metal nanoparticles. The reflective film is also required to serve as an electrode depending on the structure of the light emitting element.

The metal nanoparticles impart a reflectivity of light emitted from the light emitting layer to a composition for a reflective film, that is, a reflective film, after baking or curing. Examples of the metal nanoparticles include one or two or more mixed compositions or alloy compositions selected from the group consisting of silver, gold, platinum, palladium, ruthenium, nickel, copper, tin, indium, zinc, iron, And silver is preferable from the viewpoints of reflectivity and conductivity. The average particle diameter of the metal nanoparticles is preferably 10 to 50 nm. Here, the average particle diameter is measured using the BET method by the specific surface measurement by QUANTACHROME AUTOSORB-1. The shape of the metal nanoparticles is preferable in terms of spherical shape, plate shape, dispersibility, and reflectivity.

The composition for a reflective film preferably contains an additive from the viewpoint of the adhesiveness and reflectivity of the reflective film. The additive preferably contains at least one member selected from the group consisting of organic polymers, metal oxides, metal hydroxides, organometallic compounds and silicone oils from the viewpoint of reflectivity and adhesion.

The organic polymer used as the additive is preferably at least one member selected from the group consisting of polyvinylpyrrolidone, a copolymer of polyvinylpyrrolidone, and water-soluble cellulose, from the viewpoint of reflectivity. As the copolymer of polyvinylpyrrolidone, PVP-methacrylate copolymer, PVP-styrene copolymer, PVP-vinyl acetate copolymer and the like can be used. As the water-soluble cellulose, cellulose ethers such as hydroxypropylmethylcellulose, methylcellulose, and hydroxyethylmethylcellulose can be used.

The metal oxide used as an additive includes at least one selected from the group consisting of aluminum, silicon, titanium, zirconium, chromium, manganese, iron, cobalt, nickel, silver, copper, zinc, molybdenum, tin, indium, Are preferably used. Specific examples of the composite oxide include ITO, ATO, IZO, and AZO described above.

The metal hydroxide used as the additive includes at least one selected from the group consisting of aluminum, silicon, titanium, zirconium, chromium, manganese, iron, cobalt, nickel, silver, copper, zinc, molybdenum, tin, indium, Are preferred.

Examples of the organic metal compound used as the additive include metal soap containing at least one member selected from the group consisting of silicon, titanium, zirconium, chromium, manganese, iron, cobalt, nickel, silver, copper, zinc, molybdenum, , Metal complexes, metal alkoxides or hydrolysates of metal alkoxides are preferred. For example, metal soap may be chromate acetate, manganese formate, iron citrate, cobalt formate, nickel acetate, citric acid, copper acetate, copper citrate, tin acetate, zinc acetate, zinc oxalate and molybdenum acetate. The metal complexes include an acetylacetone zinc complex, an acetylacetone chromium complex, and an acetylacetone nickel complex. The metal alkoxide may be titanium isopropoxide, methyl silicate, isocyanatopropyl trimethoxysilane, aminopropyltrimethoxysilane, or the like.

As the silicone oil used as an additive, both of a straight silicone oil and a modified silicone oil can be used. The modified silicone oil may further contain an organic group introduced into a part of the side chain of the polysiloxane (side-chain type), an organic group introduced at both ends of the polysiloxane (both-end type) (Single-ended type) in which a group is introduced, and a part of side chains of polysiloxane and organic groups introduced at both ends (both side-chain type). The modified silicone oil includes a reactive silicone oil and a non-reactive silicone oil, both of which can be used as additives of the present invention. The reactive silicone oil refers to amino-modified, epoxy-modified, carboxy-modified, carbinol-modified, mercapto-modified, and heterogeneous functional group-modified (epoxy group, amino group, polyether group) Ether modification, methylstyryl modification, alkyl modification, high fatty acid ester modification, fluorine modification, and hydrophilic special modification.

It is preferable that the composition for a reflective film contains a dispersion medium from the viewpoint of coatability. The dispersion medium to be used is the same as the composition for a reflectively reflective film.

When the amount of the metal nanoparticles is 75 parts by mass or more based on 100 parts by mass of the composition for a reflective film excluding the dispersion medium, it is preferable from the viewpoint of reflectivity, and more preferably 80 parts by mass or more. When the amount is 95 parts by mass or less, it is preferable from the viewpoint of adhesion of the reflective film, and more preferably 80 parts by mass or more. When conductivity is imparted to the reflective film, it is preferably 75 parts by mass or more based on 100 parts by mass of the reflective film, and more preferably 80 parts by mass or more.

The dispersion medium is preferably 50 to 95 parts by mass based on 100 parts by mass of the composition for a reflective film, from the viewpoint of coatability.

It is preferable that a low-resistance agent or a water-soluble cellulose derivative is added to the composition for a reflective film depending on the component to be used. As the low resistance agent, one or two or more selected from the group consisting of cobalt, iron, indium, nickel, lead, tin, titanium and zinc minerals and organic acid salts is more preferable. For example, a mixture of nickel acetate and ferric chloride, zinc naphthenate, a mixture of tin octylate and antimony chloride, a mixture of indium nitrate and lead acetate, and a mixture of titanium acetylacetate and cobalt octylate. The low resistance agent is preferably added in an amount of 0.2 to 15 parts by mass based on 100 parts by mass of the composition for a reflective film. The water-soluble cellulose derivative is a non-ionizing surfactant and has a much higher ability to disperse the transparent conductive particles even when added in a small amount as compared with other surfactants. Further, transparency of the reflectively reflective transparent film formed by addition of the water-soluble cellulose derivative is also improved . Examples of the water-soluble cellulose derivative include hydroxypropylcellulose, hydroxypropylmethylcellulose and the like. The water-soluble cellulose derivative is preferably added in an amount of 0.2 to 5 parts by mass based on 100 parts by mass of the composition for a reflectively reflective film.

The composition for a reflective film may further contain an antioxidant, a leveling agent, a thixotropic agent, a filler, a stress relieving agent, and other additives in a range that does not impair the object of the present invention.

[Composition for protective film]

The composition for a protective film for a light-emitting element (hereinafter referred to as a composition for a protective film) contains a binder. The composition for a protective film can form a protective film. When the reflective film has a vacancy, it permeates the reflective film to contain a binder at the interface between the vacancy and / or reflective film and the reflectively reflective film of the reflective film, And the adhesion strength of the reflectively reflective transparent film can be increased.

It is preferable that the binder contains at least one or both of an organic or inorganic base material of a polymer type binder or an inorganic base material of a non-polymer type binder which is cured by being irradiated with ultraviolet rays, heated, or irradiated with ultraviolet rays. The organic base material of the polymer type binder preferably contains one or more kinds selected from the group consisting of acrylic, epoxy, urethane, acrylic urethane, epoxyacrylic, cellulose and siloxane polymers.

As the acrylic binder, an acrylic polymer obtained by adding a photopolymerization initiator to an acrylic monomer, irradiating the mixture with ultraviolet light (UV), and photopolymerizing the acrylic polymer is used. Examples of the acrylic monomer include 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, neopentyl glycol diacrylate, tetramethylolmethane tetraacrylate, ditrimethylol propane tetraacrylate, 1,9-nono One or two or more single monomers or mixed monomers selected from the group consisting of N, N-diol acrylate, tripropylene glycol diacrylate, ethoxy isocyanuric acid triacrylate and tetramethylolmethane tetraacrylate can be used . To these monomers, a solvent such as MIBK (methyl isobutyl ketone), PGME (1-methoxy-2-propanol) or PGMEA (propylene glycol monomethyl ether acetate) is preferably added. However, as the general organic solvent capable of dissolving the above-mentioned monomer, it is preferable to use an organic solvent such as ethanol, methanol, benzene, toluene, xylene, NMP (N-methylpyrrolidone), acrylonitrile, acetonitrile, THF (tetrahydrofuran) Ethyl carbitol, ethyl carbitol acetate, IPA (isopropyl alcohol), acetone, DMF (dimethyl carbonate), methyl ethyl ketone (MEK), butyl carbitol, butyl carbitol acetate, butyl cellosolve, butyl cellosolve acetate, Formamide), DMSO (dimethylsulfoxide), piperidine, phenol and the like can be used. Examples of the photopolymerization initiator include 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl] -2-methyl-propan- Methyl-1-propan-1-one, and the like. The acrylic monomer can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to coat. The photopolymerization initiator is added in an amount of 0.1 to 30 parts by mass based on 100 parts by mass of the acrylic monomer. This is because if the addition amount of the photopolymerization initiator is less than 0.1 part by mass based on 100% by mass of the acrylic monomer, the curing becomes insufficient, and if it exceeds 30 parts by mass, the cured film (protective film) is discolored or the stress remains, to be. Thus, a mixed solution obtained by adding a solvent and a photopolymerization initiator to the acrylic monomer and stirring is used as the base liquid of the protective film composition. When a solvent and a photopolymerization initiator are added to the acrylic monomer and the resulting mixed solution obtained by stirring is not uniform, it may be heated to about 40 캜.

As the epoxy-based binder, an epoxy polymer obtained by adding a solvent to an epoxy resin and stirring the mixture, adding a heat curing agent to the mixture, and stirring the resultant mixture is heated. Examples of the epoxy resin include biphenyl type epoxy resin, cresol novolak type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and naphthalene type epoxy resin. As the solvent, BCA (butyl carbitol acetate), ECA (ethyl carbitol acetate), BC (butyl carbitol) and the like can be used. However, as the general organic solvent capable of dissolving the epoxy resin, it is preferable to use an organic solvent such as ethanol, methanol, benzene, toluene, xylene, PGME (1-methoxy-2-propanol), PGMEA (propylene glycol monomethyl ether acetate) (N-methylpyrrolidone), MIBK (methyl isobutyl ketone), acrylonitrile, acetonitrile, THF (tetrahydrofuran), ethyl acetate, MEK (methyl ethyl ketone), butyl carbitol, butyl carbitol acetate, Butyl cellosolve acetate, ethyl carbitol, ethyl carbitol acetate, IPA (isopropyl alcohol), acetone, DMF (dimethylformamide), DMSO (dimethyl sulfoxide), piperidine, Can be used. Examples of the thermosetting agent include 2-ethyl-4-methylimidazole, boron fluoride / monoethanolamine, DICY (dicyandiamide), diethylaminopropylamine, isophoronediamine, diaminodiphenylmethane, piperidine , 2,4,6-tris- (dimethylaminomethyl) phenol, 2-methylimidazole, hexahydrophthalic anhydride, 7,11-octadecane diene-1,18-dicarbohydrazide and the like can be used . The epoxy resin can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to coat. The heat curing agent is added in an amount of 0.5 to 20 parts by mass based on 100 parts by mass of the epoxy resin. If the addition amount of the thermosetting agent is less than 0.5 parts by mass based on 100 parts by mass of the epoxy resin, the curing becomes insufficient. When the amount exceeds 20 parts by mass, a large internal stress is generated in the cured product (protective film), resulting in poor adhesion. Thus, a mixed solution obtained by adding a solvent and a thermosetting agent to the epoxy resin and stirring is used as the base liquid for the protective film composition. When the solvent is added to the epoxy resin and the mixed liquid obtained by stirring is not uniform, it may be heated to about 40 캜.

The cellulose-based binder is obtained by adding a solvent to a cellulosic polymer and stirring the mixture, adding gelatin to the mixture, and stirring the mixture to obtain a mixture. Examples of the cellulose-based polymer include water-soluble cellulose derivatives such as hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose, and hydroxyethylmethylcellulose. As the solvent, IPA (isopropyl alcohol), ethanol, methanol, PGME (propylene glycol monomethyl ether), PGMEA (propylene glycol monomethyl ether acetate), MIBK (methyl isobutyl ketone), acetone and the like can be used. The cellulose-based polymer can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to be coated. Gelatin is added in an amount of 0.1 to 20 parts by mass based on 100 parts by mass of the cellulose-based polymer. This is because, when the amount of gelatin added is less than 0.1 parts by mass or more than 20 parts by mass based on 100 parts by mass of the cellulose-based polymer, a viscosity suitable for application is not obtained. Thus, a mixed solution obtained by adding a solvent and gelatin to the cellulosic resin and stirring is used as the base solution of the protective film composition. Further, the solvent and gelatin are added to the cellulose-based polymer, and the mixture is heated by heating at about 30 DEG C and stirred to make the mixture liquid homogeneous.

The urethane binder using the thermosetting urethane resin is prepared as follows. First, an excessive amount of a polyisocyanate compound represented by tolylene diisocyanate (TDI), diphenylmethane isocyanate (MDI) or the like is reacted with a polyol component represented by a polyhydric alcohol compound such as trimethylolpropane or neopentyl glycol, To obtain an active isocyanate group-containing urethane prepolymer. Next, a block agent such as a phenol-based group represented by methylphenol, a lactam-based group represented by -butyrolactam, or an oxime-based group represented by methylethylketone oxime is reacted with the urethane prepolymer containing the terminal active isocyanate groups . Examples of the solvent include ketones, alkylbenzenes, cellosolves, esters, and alcohols. Specific examples of the ketone include acetone, methyl ethyl ketone and the like. Specific examples of the alkylbenzenes include benzene, toluene, and the like. Specific examples of the cellosolve include methylcellosolve and butylcellosolve. Specific examples of the esters include butyl cellosolve acetate and butyl acetate. Specific examples of the alcohols include isopropyl alcohol and butyl alcohol. On the other hand, a polyamine is used as a thermosetting agent (reacting agent). Specific examples of polyamines include N-octyl-N-aminopropyl-N'-aminopropylpropylenediamine, N-lauryl-N-aminopropyl-N'-aminopropylpropylenediamine, N-myristyl- Propyl-N'-aminopropylpropylenediamine, N-octyl-N-aminopropyl-N ', N'-di (aminopropyl) propylenediamine and the like. The urethane prepolymer containing a terminal active isocyanate group obtained by reacting the polyol component with an isocyanate compound was blocked with a block agent to prepare a block polyisocyanate. The equivalent ratio of the amino group contained in the polyamine to the isocyanate group of the block polyisocyanate is preferably around 1 (in the range of 0.7 to 1.1). This is because if the equivalent ratio of the amino group possessed by the polyamine to the isocyanate group of the block polyisocyanate is less than 0.7 or more than 1.1, either the block polyisocyanate or the polyamine becomes larger and the reaction becomes insufficient. The urethane polymer can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to be coated.

Examples of the acrylic urethane binder include a violet light UV-3310B or violet light UV-6100B (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), EBECRYL4820 or EBECRYL284 (manufactured by Nippon Synthetic Company), which contains a urethane acrylate oligomer and is cured by irradiation with ultraviolet (Trade name, manufactured by Syntec Corporation), U-4HA or UA-32P (manufactured by Shin-Nakamura Chemical Co., Ltd.). If necessary, a photopolymerization initiator (for example, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl- The curing property can be improved. As the solvent, ketones, alkylbenzenes, cellosolves, esters, alcohols and the like are used. Specific examples of the ketone include acetone, methyl ethyl ketone and the like. Specific examples of the alkylbenzenes include benzene, toluene, and the like. Specific examples of the cellosolve include methyl cellosolve and butyl cellosolve, and specific examples of the esters include butyl cellosolve acetate and butyl acetate. Specific examples of the alcohols include isopropyl alcohol and butyl alcohol. The photopolymerization initiator is added in an amount of 0.1 to 30 parts by mass based on 100 parts by mass of the acrylic urethane polymer, if necessary. This is because the curing becomes insufficient when the addition amount of the photopolymerization initiator is less than 0.1 part by mass, and the internal stress of the protective film becomes large if it exceeds 30 parts by mass, resulting in poor adhesion. The acrylic urethane-based monomer can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to be coated.

As the epoxy acrylic binder, an epoxyacryl polymer is used. Examples of the epoxy acryl-based polymer include bisphenol A type epoxy acrylate (for example, NK Oligo EA-1020 manufactured by Shin Nakamura Chemical Co., Ltd.) and 1,6-hexane diol diglycidyl ether diacrylate NK Oligo EA-5521 manufactured by Nakamura Chemical Industries, Ltd.) and the like can be used. Neopol 8318 or Neopol 8355 manufactured by Nippon Yu Pica may be used. Examples of the solvent include ketones, alkylbenzenes, cellosolves, esters, and alcohols. Specific examples of the ketone include acetone, methyl ethyl ketone and the like. Specific examples of the alkylbenzenes include benzene, toluene, and the like. Specific examples of the cellosolve include methylcellosolve and butylcellosolve. Specific examples of the esters include butyl cellosolve acetate and butyl acetate. Specific examples of the alcohols include isopropyl alcohol and butyl alcohol. A thermosetting agent or a photopolymerization initiator is added to the epoxyacryl-based polymer as needed. Then, it is heat-cured by a heat curing agent or a photopolymerization initiator, is UV-cured, or is heat cured after UV curing. The epoxy acryl-based polymer can be used by adjusting to a viscosity which is easily diluted with any of the above-described solvents and is easy to coat.

As the siloxane-based binder, a siloxane-based polymer is used. As the siloxane-based polymer, polydimethylsiloxane, polymethylhydrogensiloxane, polymethylphenylsiloxane and the like can be used. As the siloxane-based polymer shown here, both of a straight silicone oil and a modified silicone oil can be used. Examples of the modified silicone oil include those obtained by introducing an organic group into a part of side chains of the polysiloxane (side chain type), ones obtained by introducing an organic group at both ends of the polysiloxane (both end types), and either ends of the polysiloxane An organic group introduced (one terminal type), a part of the side chain of the polysiloxane and an organic group introduced into both terminals (both side terminal type), and the like. The modified silicone oil includes a reactive silicone oil and a non-reactive silicone oil, and both of them can be used. The reactive silicone oil refers to an amino group, an epoxy group, a carboxy group, a carbinol group, a carbinol group, a mercapto group, or a heterobifunctional group (epoxy group, amino group or polyether group). Examples of the nonreactive silicone oil include polyether- Alkyl modification, higher fatty acid ester modification, fluorine modification or hydrophilic modification. As the solvent, ketones, alkylbenzenes, cellosolves, esters, alcohols and the like are used. Specific examples of the ketone include acetone, methyl ethyl ketone and the like. Specific examples of the alkylbenzenes include benzene, toluene, and the like. Specific examples of the cellosolve include methylcellosolve and butylcellosolve. Specific examples of the esters include butyl cellosolve acetate and butyl acetate. Specific examples of the alcohols include isopropyl alcohol and butyl alcohol. A thermosetting agent or a photopolymerization initiator can be added to the siloxane-based polymer if necessary, but when the film is cured even without adding the thermosetting agent, a thermosetting agent is unnecessary. The siloxane-based polymer can be used by adjusting to a viscosity which is easily diluted with any of the above-mentioned solvents and is easy to be coated.

The inorganic base material of the polymer type binder preferably contains at least one selected from the group consisting of metal soaps, metal complexes, metal alkoxides and hydrolyzates of metal alkoxides. The inorganic base material of these polymer type binders is changed from an organic base to an inorganic base material by heating. That is, a film having properties of an inorganic base material can be formed by firing. The metal contained in the metal soap, the metal complex, the metal alkoxide or the hydrolyzate of the metal alkoxide is preferably one or more selected from the group consisting of aluminum, silicon, titanium, zirconium and tin. Examples of the metal soap include chrome acetate, manganese formate, iron citrate, cobalt formate, nickel acetate, citric acid, copper acetate, copper citrate, tin acetate, zinc acetate, zinc oxalate and molybdenum acetate. As the metal complex, an acetylacetone zinc complex, an acetylacetone chromium complex, an acetylacetone nickel complex and the like can be used. As the metal alkoxide, titanium isopropoxide, methyl silicate, isocyanatopropyl trimethoxysilane, aminopropyltriethoxysilane and the like can be used.

On the other hand, as the inorganic base material of the non-polymer type binder, a SiO ₂ binder may be used. This SiO ₂ binder is produced as shown in the following example. First, an HCl aqueous solution is prepared by dissolving HCl in purified water while stirring. Next, tetraethoxysilane and ethyl alcohol are mixed, and the HCl aqueous solution is added to the mixed solution, followed by heating to react. Thus, a SiO ₂ bonding agent is produced. The non-polymer type binder may be one or two selected from the group consisting of metal soap, metal complex, metal alkoxide, hydrolyzate of metal alkoxide, halosilanes, 2-alkoxyethanol, Or more. The hydrolyzate of the metal alkoxide includes a sol gel. The metal contained in the metal soap, the metal complex, the metal alkoxide or the hydrolyzate of the metal alkoxide is preferably one or more selected from the group consisting of aluminum, silicon, titanium, zirconium and tin. As the metallic soap, there can be used chromic acid acetate, manganese formate, iron citrate, cobalt formate, nickel acetate, citric acid, copper acetate, copper citrate, tin acetate, zinc acetate, zinc oxalate and molybdenum acetate. Examples of the metal complex include an acetylacetone zinc complex, an acetylacetone chromium complex, and an acetylacetone nickel complex. Examples of the metal alkoxide include titanium isopropoxide, methyl silicate, isocyanatopropyl trimethoxy silane, aminopropyl tri Ethoxy silane, and the like. Examples of the halosilanes include chlorosilane, bromosilane, and fluorosilane. As the 2-alkoxyethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol and the like can be used. As the? -diketone, 2,4-pentanedione, 1,3-diphenyl-1,3-propanedione and the like can be used. As the alkyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate and the like can be used.

The protective film composition may contain one or more kinds selected from the group consisting of a silane coupling agent, an aluminum coupling agent and a titanium coupling agent. When the protective film composition contains a silane coupling agent, an aluminum coupling agent or the like, the adhesion of the protective film to the reflective film can be further improved. Therefore, when using a step of forming a plurality of light emitting elements on one substrate, dividing the light transmitting substrate from the reflective film side by dicing, and dividing the light emitting device into the respective light emitting elements, It is possible to suppress peeling from the reflective film.

The composition for a protective film may contain one or more kinds of metal oxide fine particles or flat particles selected from the group consisting of colloidal silica, fumed silica particles, silica particles, mica particles and smectite particles. The colloidal silica is a colloid of SiO ₂ or a hydrate thereof and has an average particle diameter of 1 to 100 nm, preferably 5 to 50 nm, which does not have a constant structure. The fumed silica particles are produced by vaporizing a silicon chloride and oxidized in a gaseous state in a high temperature salt to have an average particle diameter of 1 to 50 nm, preferably 5 to 30 nm. The silica particles are particles having an average particle diameter of 1 to 100 nm, preferably 5 to 50 nm. The mica particles are particles having an average particle diameter of 10 to 50000 nm, preferably an average particle diameter of 1 to 20 mu m, and an average thickness of 10 to 100 nm, which are produced by a synthetic method. The smectite particles are one kind of ion-exchangeable layered silicate compounds having a crystal structure in which faces constituted by ionic bonds or the like are stacked in parallel with each other by weak bonding force, and the particles are particles having an average particle size of 10 to 100,000 nm, Is a flat particle having a diameter of 1 to 20 mu m and an average thickness of 10 to 100 nm. When the composition for a protective film contains colloidal silica, fumed silica particles and the like, the hardness of the protective film can be further increased. Therefore, even if burrs and debris remaining in the separation grooves are formed by dicing after removing the separation grooves with an air knife or the like, the abrasion resistance and impact resistance of the protective film are good. Therefore, . The amount of these added is preferably from 0.1 to 30 parts by mass, more preferably from 0.2 to 20 parts by mass, per 100 parts by mass of the protective film composition. If the amount is less than 0.1 part by mass, the effect is not obtained well, whereas if it exceeds 30 parts by mass, the adhesion property is likely to be deteriorated. In the present invention, the average particle diameter of each particle and each fine particle is measured as follows. Refers to a 50% average particle size (D ₅₀ ) calculated by a laser diffraction / scattering type particle size distribution analyzer (manufactured by Horiba Ltd., model number: LA-950) The value of the number-based average particle diameter by the laser diffraction / scattering type particle size distribution measuring apparatus was determined by using a scanning electron microscope (S-4300SE and S-900, manufactured by Hitachi High- Of the average particle diameter of the 50 particles. The average diameter and the average thickness of the above-described flat particles, and the average diameter and average thickness of each flat fine particle described later are also measured in the same manner as described above.

The reason why the average particle diameter of the colloidal silica is limited to the range of 1 to 100 nm is because when the particle diameter is less than 1 nm, the colloidal particles become unstable and tend to flocculate, and when the particle diameter exceeds 100 nm, the particle diameter becomes large. The reason why the sizes of the fumed silica particles, silica particles, mica particles and smectite particles are limited to the above range is that the particle size is available or the size range does not become larger than the thickness of the lower layer (reflective film).

The composition for the protective film may be one or two or more metals selected from the group consisting of gold, platinum, palladium, ruthenium, nickel, copper, tin, indium, zinc, iron, chromium, manganese and aluminum, Containing fine particles or flat fine particles. The average particle diameter of these fine particles is set in the range of 1 to 50000 nm, preferably 100 to 5000 nm. The average diameter of the flat fine particles is preferably 1 to 50000 nm, and the average thickness of the flat fine particles is preferably 100 to 20000 nm. When the composition for a protective film contains fine particles such as gold or platinum or flat fine particles, more flexibility can be imparted to the protective film. Therefore, even when stress is generated in the protective film at the time of forming the separation groove by dicing, the stress can be relaxed by the ductility and the electrical property of the protective film. The reason why the size of the metal fine particles is limited to the above range is because the size of the obtained fine particles is limited and the size of the flat fine particles of the metal is limited to the above range, . The amount of these fine particles or flat fine particles to be added is preferably 0.1 to 30 parts by mass, more preferably 0.2 to 20 parts by mass. This is because if the amount is less than 0.1 part by mass, the effect is not obtained well, while if it exceeds 30 parts by mass, the adhesion is likely to be deteriorated. The content of the metal or metal oxide in the fine particles or the flat fine particles is set to a range of 70 mass% or more, preferably 80 to 100 mass%. This is because when the amount is less than 70% by mass, the workability of the protective film deteriorates.

The composition for the protective film may further contain an antioxidant, a leveling agent, a thixotropic agent, a stress relieving agent, and other additives as needed within the range not impairing the object of the present invention.

[Light Emitting Element]

The light-emitting element of the present invention is a light-emitting element comprising a light-emitting layer, a light-transmitting substrate, a reflectively reflective transparent film, and a reflective film for reflecting light emitted from the light-emitting layer in this order, wherein the reflectively reflective transparent film contains a transparent binder .

1 is a cross-sectional view of an example of a light emitting device. The light emitting element 1 is provided in the order of the light emitting layer 40, the transparent substrate 30, the reflectively reflective transparent film 20, and the reflective film 10. Typically, the light emitting layer 40 is bonded to the support substrate 70 by the adhesive layer 60, and the light emitting layer 40 is subjected to desired wiring, and then sealed with the sealing material 50.

Fig. 2 is a cross-sectional view showing a preferable example of the light emitting element. When the light emitting element 1 is provided in this order of the light emitting layer 41, the transparent substrate 31, the reflectively reflective transparent film 21, the reflective film 11 and the protective film 81, the reflective film 11 Can be further improved and the peeling of the reflection film 11 from the substrate 31 in the dicing step can be suppressed. The protective film 81 is more preferable because it can be produced by a wet coating method if it contains a binder, but it is possible to improve the heat resistance and corrosion resistance of the reflective film 11 even if it is produced by a vacuum film forming method or the like.

Fig. 3 is a cross-sectional view showing a more preferable example of the light emitting element. The luminous means 3 is provided between the transparent substrate 32 and the reflective film 12 in such a manner that the transparent reflective film 22 is provided between the transmissive substrate 32 and the reflective transparent film 22, A low refractive index enhancement transparent reflective film 222 on the reflective film 12 side, and a high refractive index enhancement transparent reflective film 221 on the reflective film 12 side. By making the reflectively reflecting transparent film 22 have a two-layer structure, the reflected light by the reflecting film 12 can be increased. Further, the reflectively reflective transparent film 22 is formed on the transparent substrate 32 side from the side of the translucent substrate 32, from the side of the translucent substrate 32 to the reflective transparent film, the high refractive index enhancement transparent film, the low refractive index enhancement transparent film, The reflection light from the reflection film 12 can be further increased. Further, as described above, it is preferable that the light emitting element has the protective film 82.

Hereinafter, the reflectively reflective transparent film, the reflective film, the protective film, and the adhesive layer will be described in this order.

[Transparent reflective film]

When the reflectively reflective transparent film is formed between the transmissive substrate and the reflective film, the reflectance of the reflective film that reflects the light emitted from the light-emitting device can be increased to increase the luminous efficiency of the light-emitting device. The translucent binder in the reflectively reflective transparent film is as described above, and preferably contains transparent particles, a coupling agent and the like.

The reflectively reflective transparent film may further contain a filler, a stress relaxation agent, and other additives as needed within the range not impairing the object of the present invention.

The thickness of the reflectively reflecting transparent film is preferably 0.01 to 0.5 mu m from the viewpoint of adhesion, and more preferably 0.02 to 0.1 mu m. When the thickness of the reflectively reflecting transparent film is less than 0.01 탆 or more than 0.5 탆, the antireflection effect is not sufficiently obtained.

It is also preferable that the reflectively reflective transparent film has two layers and the refractive index of the reflectively reflective transparent film (low refractive index retroreflective transparent film) on the transparent substrate side is lower than the refractive index of the reflectively reflective transparent film (high refractive index retroreflective transparent film) , The reflection light by the reflection film is increased as described above.

[Reflective film]

The reflective film reflects the light of the light emitting layer that has passed through the gas. The reflective film preferably contains metal nanoparticles and further contains an additive. The metal nanoparticles and additives are as described above.

The content of the additive is preferably 0.1 to 25 parts by mass, more preferably 0.2 to 10 parts by mass based on 100 parts by mass of the reflectively reflective transparent film. If it is at least 0.1 part by mass, the adhesive strength to the reflectively reflective transparent film is good, and if it is less than 25 parts by mass, film unevenness at the time of film formation hardly occurs.

The thickness of the reflective film is preferably 0.05 to 1.0 탆, more preferably 0.1 to 0.5 탆, from the viewpoint of reflectivity and conductivity.

In the range of the wavelength: 380 to 780 nm, when the pores present on the surface of the reflective film on the side of the transparent substrate have an average diameter of 100 nm or less, an average depth of 100 nm or less and a number density of 30 pb / , A high diffusive reflectance of 80% or more of the wavelength of the visible light can be achieved. Generally, the reflection spectrum shows a high reflectance on the long wavelength side and a low reflectance on the short wavelength side. If the average diameter of the pores exceeds 100 nm, the inflection point at which the reflectance starts to decrease is shifted to the longer wavelength side, and a good reflectance can not be obtained. Therefore, the average diameter is preferably 100 nm or less. When the average depth of the pores exceeds 100 nm, the gradient of the reflection spectrum becomes large and a good reflectance can not be obtained. Therefore, the average depth of the pores is preferably 100 nm or less. When the number density of the pores exceeds 30 p / m2, the reflectance on the longer wavelength side is lowered and a good reflectivity can not be obtained. Therefore, the number density of the pores is preferably 30 p / m2 or less.

[Shield]

The protective film enhances the heat resistance and corrosion resistance of the reflective film and also enhances the adhesion between the transparent substrate and the reflective film and suppresses peeling of the reflective film when dicing is used in the manufacturing process of the light emitting device. The protective film contains a binder, and the binder is as described above.

The thickness of the protective film is preferably 0.01 to 0.5 mu m, more preferably 0.01 to 0.2 mu m from the viewpoint of heat resistance and corrosion resistance.

The adhesive layer can be generally bonded using a resin paste, a metal paste, solder, or the like.

[Manufacturing Method of Light Emitting Element]

A method of manufacturing a light emitting device of the present invention is a method of manufacturing a light emitting device comprising the steps of applying a composition for a reflective and reflective transparent film containing a translucent binder on a transparent substrate by a wet coating method, A reflective film containing a metal nanoparticle and an additive is coated on a film by a wet coating method and then baked or cured to form a reflective film and a light emitting layer is formed on the opposite side of the reflective film of the transparent substrate do. Here, when the reflectively reflective transparent film is composed of two or more layers of a low refractive index increase reflective transparent film and a high refractive index retroreflective transparent film, a composition for a low refractive index retroreflective film, a composition for a high refractive index retroreflective film In this order.

When a protective film is formed by applying a protective film composition containing a binder on a reflective film after forming a reflective film and forming a light emitting layer by wet coating method and then baking or curing it, The heat resistance and the corrosion resistance can be enhanced and peeling of the reflective film when dicing is used in the manufacturing process of the light emitting device can be suppressed.

First, a composition for an ITO film containing a light-transmitting binder is applied on a light-transmitting substrate by a wet coating method. The application here is such that the thickness after firing is preferably 0.01 to 0.5 mu m, more preferably 0.02 to 0.1 mu m. Subsequently, the coating film is dried at a temperature of 120 to 350 ° C, preferably 150 to 250 ° C, for 5 to 60 minutes, preferably 15 to 40 minutes. Thus, an anti-reflective film is formed.

The light transmitting substrate is not particularly limited as long as it can form a light emitting layer, but a sapphire substrate is preferable from the viewpoint of light transmittance and heat radiation.

The composition for a reflectively reflective film may be prepared by mixing a desired component with a light-transmitting binder, if necessary, by dispersing transparent particles or the like by a conventional method using a paint shaker, a ball mill, a sand mill, a centri mill or three rolls . It may, of course, be produced by a conventional stirring operation. It is also preferable to mix the components except for the transparent particles and then mix them with the dispersion medium containing the transparent particles previously dispersed separately from the viewpoint of easily obtaining a homogeneous composition for an ITO film.

The wet coating method is preferably any one of a spray coating method, a dispenser coating method, a spin coating method, a knife coating method, a slit coating method, an inkjet coating method, a screen printing method, an offset printing method and a die coating method. But are not limited to, all methods are available.

The spray coating method is a method in which a composition for an anti-reflective film is applied to a translucent substrate in the form of mist by compressed air, or the dispersion itself is pressed to form a mist and applied to a transparent substrate. The dispenser coating method is a method in which, for example, a composition for an anti-reflective film is put into a syringe and the piston of the syringe is pressed, the dispersion is discharged from the fine nozzles at the tip of the syringe and is applied to the transparent substrate. The spin coating method is a method in which a composition for an anti-reflective film is dropped onto a rotating transparent substrate, and a composition for the anti-reflective coating is dropped on the periphery of the transparent substrate by centrifugal force. In the knife coating method, a translucent substrate having a predetermined gap with the tip of a knife is formed so as to be movable in the horizontal direction, and a composition for an increase / decrease reflective film is supplied onto the translucent substrate on the upstream side from the knife, As shown in Fig. The slit coating method is a method in which a composition for an anti-reflective film is outflowed from a narrow slit and applied on a transparent substrate. The ink-jet coating method is a method in which an ink cartridge of a commercially available ink-jet printer is filled with a composition for a reflective / reflective film and ink-jet printed on a transparent substrate. In the screen printing method, a silk is used as a pattern indicating material, and a composition for an anti-reflection film is transferred onto a transparent substrate through a plate image formed thereon. The offset printing method uses a water repellent property of a composition for an anti-reflective film for transferring a composition for a reflective / reflective film attached to a plate to a rubber sheet once from the plate without transferring the film directly to the light- Printing method. The die coating method is a method of distributing a composition for an anti-reflective and transparent film supplied into a die into a manifold, extruding the thin film from the slit, and coating the surface of the translucent substrate to be driven. The die coating method includes a slot coat method, a slide coat method, and a curtain coat method.

Finally, the translucent substrate having the anti-reflective coating film is applied to the substrate in an atmosphere of inert gas such as nitrogen or argon, preferably at a temperature of 130 to 250 ° C, more preferably 180 to 220 ° C for 5 to 60 minutes , Preferably 15 to 40 minutes. When the binder reacts by hydrolysis or the like, it can be cured at a lower temperature.

The reason why the firing temperature of the translucent substrate having a coating film is set in the range of 130 to 250 占 폚 is that if it is less than 130 占 폚, the problem of lack of curing in the reflective film occurs. On the other hand, if the temperature exceeds 250 ° C, the production advantage of a low-temperature process can not be utilized. That is, the manufacturing cost is increased and the productivity is lowered. Further, when the light emitting layer is formed and mounted on the light transmitting substrate in advance, the light emitting layer is relatively weak to heat, and the light emitting efficiency is lowered by the firing process.

The reason why the firing time of the translucent substrate having a coating film is set in the range of 5 to 60 minutes is that if the firing time is less than the lower limit value, the problem of insufficient binder firing in the reflective film occurs. If the firing time exceeds the upper limit value, the production cost is increased more than necessary and the productivity is lowered. Further, when the light emitting layer is formed in advance on the light transmitting substrate, the light emitting efficiency of the light emitting layer is lowered.

The method of preparing the composition for a reflective film, the wet coating method, and the method of baking or curing are almost the same as those of the composition for a reflectively reflective film, but in the case of a composition for a reflective film, the thickness after baking is preferably 0.05 to 1.0 μm Preferably 0.1 to 0.5 mu m.

The method of forming the light emitting layer on the opposite side of the reflective film of the translucent substrate is not particularly limited and a known method such as organic vapor growth (MOCVD), hydride vapor growth (HVPE), molecular beam epitaxial growth do.

As described above, since the vacuum coating process such as the vacuum evaporation process and the sputtering process can be eliminated as much as possible by using the wet coating method of the present invention, the retroreflective transparent film can be produced at lower cost, A light emitting element having a high light emitting efficiency can be manufactured easily and at low cost.

When a protective film is formed by applying a protective film composition containing a binder on a reflective film after forming the reflective film and forming the light emitting layer by a wet coating method and then baking or curing it, It is possible to further improve the heat resistance and corrosion resistance. In addition, adhesion between the light-transmitting substrate and the light-emitting layer is enhanced, and peeling of the reflective film when dicing is used in the manufacturing process of the light-emitting device can be suppressed. Therefore, as described above, after forming the reflective film and before forming the light emitting layer, a composition for a protective film containing a binder is further coated on the reflective film by a wet coating method and then baked or cured to form a protective film .

The binder for the protective film is as described above. The method for producing the protective film composition and the wet coating method are the same as those for the reflective film. In the case of the protective film composition, the thickness after firing is preferably 0.01 to 0.5 占 퐉 Preferably 0.01 to 0.2 mu m. Depending on the kind of the binder of the protective film composition, a heating method for curing or an ultraviolet irradiation method may be appropriately selected.

Examples of the method of adding the additives such as the above-mentioned necessary particles, fine particles and flat fine particles to the base liquid of the protective film composition and dispersing these additives in the base liquid include dispersion by vortex stirring such as dispenser stirring, Shear dispersion such as free agitation or three roll mill, and dispersion using beads containing a bead mill or paint shaker. It is also possible to adopt a method in which the additive is dispersed in advance in the solvent component in the base liquid in the same manner as described above. In the case where the additive itself is a dispersion liquid already dispersed by a suitable solvent, a solution mixing method using ultrasonic homogenizer or ultrasonic vibration can be used in addition to the above-mentioned method.

As described above, by using the wet coating method, it is possible to manufacture a reflectively reflective transparent film at a lower cost, and a light emitting device having a higher light emitting efficiency can be manufactured at a low cost by a simple manufacturing process.

Example

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.

[Production of a composition for a reflective / reflective film containing silsesquioxane]

Using a 500-cm3 glass four-necked flask, 140 g of trimethylmethoxysilane and 140 g of methyl alcohol were added, and while stirring, 1.7 g of 60% nitric acid dissolved in 120 g of pure water was added at once, And then reacted at 50 DEG C for 3 hours to prepare spherical silsesquioxane particles having an average particle diameter of 10 nm.

5 g of the silsesquioxane spherical particles, 10 g of the SiO ₂ binder and 85 g of ethanol were placed in a 100 cm 3 glass bottle and 100 g of zirconia beads having a diameter of 0.3 mm (manufactured by Showa Shell Chemical Co., Ltd.) Was dispersed in a paint shaker for 6 hours to prepare a composition for a reflective and transparent film containing silsesquioxane (referred to as silsesquioxane in Table 1).

[Production of a SiO ₂ binding agent;

Using a 500-cm3 glass four-necked flask, 140 g of tetraethoxysilane and 140 g of ethyl alcohol were added. A solution of 1.7 g of 60% nitric acid in 120 g of pure water was added in one portion while stirring, then prepare a SiO ₂ binding agent by reaction for 3 hours at 50 ℃.

[SiO ₂ Preparation of the binder and oxide-containing particles increased the transparent reflective film composition;

10 g of the SiO ₂ binder prepared above, 3 g of ITO particles having an average particle diameter of 25 nm and 87 g of ethanol were placed in a glass bottle having a volume of 100 cm 3 to prepare a zirconia bead having a diameter of 0.3 mm Manufactured by Showa Shell Petroleum Corporation): 100 g was dispersed in a paint shaker for 6 hours to prepare a SiO ₂ binder and a composition for an ITO particle-containing red-and-white reflective film (shown as SiO ₂ binder + ITO in Table 1).

SiO ₂ in the same manner as the binder and particle-containing ITO transparent increased reflection film composition was prepared containing the other oxide particles increases transparent reflection film composition. Here, the ZnO particles had an average particle diameter of 20 nm, the SiO ₂ particles had an average particle diameter of 10 nm, the ZrO ₂ particles had an average particle diameter of 30 nm, the TiO ₂ particles had an average particle diameter of 20 nm, ATO particles having an average particle diameter of 40 nm were used.

[Preparation of silver nanoparticle-containing reflective film composition]

Silver nitrate was dissolved in deionized water to prepare a metal salt aqueous solution. Further, sodium citrate was dissolved in deionized water to prepare an aqueous solution of sodium citrate having a concentration of 26 mass%. The granular ferrous sulfate was directly added to and dissolved in the sodium citrate aqueous solution in a nitrogen gas flow maintained at 35 ° C to prepare a reducing agent aqueous solution containing citric acid ions and ferrous ions in a molar ratio of 3: 2 .

Next, while the nitrogen gas stream was maintained at 35 占 폚, the metal salt aqueous solution was added dropwise to the reducing agent aqueous solution while stirring the magnetic stirrer in the reducing agent aqueous solution and stirring the mixture at a rotating speed of 100 rpm. Here, the addition amount of the metal salt aqueous solution to the reducing agent aqueous solution was adjusted so that the concentration of each solution was 1/10 or less of the amount of the aqueous reducing agent solution, and the reaction temperature was maintained at 40 캜 even by dropping the aqueous metal salt solution at room temperature. The mixing ratio of the reducing agent aqueous solution and the metal salt aqueous solution was such that the molar ratio of the citric acid ion and the ferrous ion in the reducing agent aqueous solution to the total atomic valence of the metal ion in the aqueous metal salt solution was all three times. After the dropwise addition of the metal salt aqueous solution to the reducing agent aqueous solution was completed, stirring of the mixed solution was further continued for 15 minutes to generate silver nanoparticles in the mixed solution to obtain silver nanoparticle dispersion in which silver nanoparticles were dispersed. The pH of the silver nanoparticle dispersion was 5.5 and the stoichiometric amount of silver nanoparticles in the dispersion was 5 g / l.

The obtained silver nanoparticle dispersion was allowed to stand at room temperature to precipitate silver nanoparticles in the dispersion, and the aggregated silver nanoparticles were separated by decantation. The separated silver nanoparticle aggregates were made into a dispersion by adding deionized water, subjected to desalting treatment by ultrafiltration, and then further washed with methanol to obtain a metal (silver) content of 50 mass%. Thereafter, centrifugal separator was used to adjust the centrifugal force of the centrifugal separator to separate silver nanoparticles having a particle diameter of more than 100 nm, thereby obtaining silver nanoparticles having a primary particle size in the range of 10 to 50 nm as a number average 71%. That is, the silver nanoparticle dispersion was obtained by adjusting the ratio of the silver nanoparticles within the range of the primary particle diameter of 10 to 50 nm to the total silver nanoparticle ratio of 100% to be 71%. The obtained silver nanoparticles were chemically modified with a protective agent for sodium citrate.

Next, 10 parts by mass of the obtained metal nanoparticles was added to and mixed with 90 parts by mass of a mixed solution containing water, ethanol and methanol to prepare a silver nanoparticle-containing reflective film composition. The metal nanoparticles constituting the composition for a reflective film contain 75% by mass or more of metal nanoparticles.

[Preparation of composition for reflective film containing silver nanoparticles and additives]

And 10 parts by mass of the obtained metal nanoparticles were added to and mixed with 90 parts by mass of a mixed solution containing water, ethanol and methanol to prepare a dispersion. To this dispersion was added polyvinylpyrrolidone (PVP, molecular weight: 360,000), 96 parts by mass of metal nanoparticles, and 4 parts by mass of PVP, to prepare a silver nanoparticle and PVP-containing reflective film composition.

A composition for a reflective film containing another additive was prepared in the same manner as the composition for a silver nanoparticle and a PVP-containing reflective film. Here, the SiO ₂ particles, the ITO particles, the ATO particles and the TiO ₂ particles were the above-mentioned average particle diameter, and the Al ₂ O ₃ particles had an average particle diameter of 50 nm. By mass. In Examples 5 to 8 and 10, the mass ratio of PVP: SiO ₂ particles and the like was adjusted to be 3: 2.

[Preparation of composition for protective film]

Neopentyl glycol diacrylate was used for the acrylic system, bisphenol A type epoxy resin was used for the epoxy system, methyl cellulose was used for the cellulose system, and diphenylmethane isocyanate and methylphenol were used for the urethane system.

[Example 1]

A composite membrane having the structure shown in Table 1 was produced. First, a composition for a reflective / transmissive film containing silsesquioxane was applied on a glass substrate as a light transmitting substrate by spin coating and baked at 160 캜 for 20 minutes in a nitrogen atmosphere to obtain a low refractive index, Film. Here, the film thickness was measured by a scanning electron microscope (SEM, apparatus names: S-4300, SU-8000) manufactured by Hitachi High-Technologies Corporation. In the other Examples and Comparative Examples, the film thicknesses were measured in the same manner. In the same manner, a high refractive index retroreflective film of 25 nm was formed. Next, a reflective film composition containing silver nanoparticles was coated on the high refractive index retroreflective film by spin coating, and the reflective film was obtained by baking at 200 캜 for 20 minutes in a nitrogen atmosphere.

[Examples 2 to 10]

The composite membranes of Examples 2 to 10 were prepared in the same manner as in Example 1 except that the constitution of Table 1 was used. Here, the protective film, was coated by a composition for the protective layer, spin coating, in the case of a SiO ₂ binding agent, in a nitrogen atmosphere, and at 160 ℃ baking 20 minutes, the coating film for the protective film of the other is, to 150 in a nitrogen atmosphere Lt; 0 > C for 15 minutes.

[Comparative Example 1]

A silver thin film having a thickness of 100 nm was formed on the glass substrate by the sputtering method of the vacuum film forming method.

[Comparative Example 2]

A silver thin film having a thickness of 100 nm was formed on a glass substrate by a sputtering method, and a titanium thin film having a thickness of 30 nm was further formed by a sputtering method.

[Measurement of reflectance]

The reflectance of Examples 1 to 10 and Comparative Examples 1 and 2 was evaluated by measuring the diffuse reflectance (initial reflectance) of a reflective film at a wavelength of 450 nm by combining an ultraviolet visible spectrophotometer and an integrating sphere. Further, the heat treatment test was conducted at 200 占 폚 for 1000 hours, and a sulfidation test was conducted as a corrosion resistance test at a hydrogen sulfide concentration of 10 ppm, a temperature of 25 占 폚, and a relative humidity of 75% RH for 504 hours. Table 1 shows the results.

As is apparent from Table 1, in Examples 1 and 2, the reflectance after the initial heat treatment was high, and the reflectance after the sulfiding test was also about 30%. On the other hand, in Comparative Example 1 produced by the sputtering method, the initial reflectance was high, but the deterioration after the heat treatment was large, and the reflectance after the sulfuration test was greatly reduced to 14%. In Examples 3 to 10, it was found that the reflectance after the initial and after the heat treatment and after the sulfuration test were all very high, and that the heat resistance and the corrosion resistance were excellent. Therefore, it is possible to fabricate a light emitting device having less deterioration even with a rise in temperature caused by a high-output light emitting layer. On the other hand, in Comparative Example 2 produced by the sputtering method, the reflectance after the sulfuration test was as low as 65%.

Industrial availability

The light emitting device of the present invention can increase the luminous efficiency of the light emitting device by providing an increase / decrease transparent film containing a light transmitting binder between the light transmitting substrate and the reflecting film. Since this reflectively reflecting transparent film can be produced by a wet coating method, the manufacturing process is simple and low cost. In addition, since the reflective film is further provided with a protective film, the heat resistance and corrosion resistance of the reflective film can be enhanced.

1, 2, 3: Light emitting element
10, 11, 12: reflection film
20, 21, 22: a reflective transparent film
221: Refractive index increase reflective reflective film
222: Refractive index increase reflective reflective film
30, 31, 32: Transparent substrate
40, 41, 42: light emitting layer
50, 51, 52: sealing material
60, 61, 62: adhesive layer
70, 71, 72: Support substrate
81, 82:

Claims (18)

A composition for a retroreflective transparent film for a light emitting device comprising a light emitting layer, a light transmitting substrate, an increase reflective transparent film having a thickness of 20 to 300 nm, and a reflective film for reflecting light emitted from the light emitting layer, Characterized in that the composition for an increase reflective transparent film for a light emitting element contains a silsesquioxane spherical particle and a light transmitting binder or an alkoxide of silicon and a non-polymeric binder containing a nitric acid catalyst A composition for a reflective (reflective) transparent film. The method according to claim 1,
Wherein the composition for an increase reflective transparent film for a light emitting device further contains transparent particles. delete delete delete delete delete 3. The method of claim 2,
Wherein the transparent particles are fine oxide particles. 3. The method of claim 2,
Wherein the transparent particles are transparent conductive oxide particles. 10. The method of claim 9,
Wherein the transparent conductive oxide particles are at least one selected from the group consisting of indium tin oxide powder, antimony doped tin oxide powder, and zinc oxide powder, ) Composition for a transparent film. 10. The method of claim 9,
Wherein the average particle diameter of the transparent conductive oxide particles is in the range of 10 to 100 nm. 3. The method according to claim 1 or 2,
Wherein the composition for an increase reflective transparent film comprises a composition for a high refractive index retroreflective film and a composition for a low refractive index retroreflective film for a retroreflective transparent film for a light emitting device, Composition. A light-emitting layer, a light-transmitting substrate, an increase reflective transparent film having a thickness of 20 to 300 nm, and a reflection film for reflecting light emitted from the light-emitting layer in this order, , A composition for a retroreflective transparent film containing a silsesquioxane spherical particle and a translucent binder, or a composition for a retroreflective transparent film containing an alkoxide of silicon and a non-polymeric binder containing a nitric acid catalyst Emitting device. 14. The method of claim 13,
Wherein the increasingly reflective transparent film has a two-layer structure and the refractive index of the increasingly reflective transparent film on the side of the transparent substrate is lower than the refractive index of the increasingly reflective transparent film on the side of the reflective film. 14. The method of claim 13,
Further, the reflective film has a protective film containing a binder on the opposite side of the increasingly reflective transparent film. 16. The method according to any one of claims 13 to 15,
Wherein the increasingly reflective transparent film and / or the reflective film is produced by a wet coating method. A transparent conductive film containing a silsesquioxane spherical particle and a transparent binder and a non-polymeric binder containing a silicon alkoxide and a nitric acid catalyst on the light-transmitting substrate, The composition is coated by a wet coating method and then baked or cured to form an increase reflective transparent film having a thickness of 20 to 300 nm and a metal nano particle and an additive Is coated by a wet coating method and then baked or cured to form a reflective film, a light-emitting layer is formed on the opposite surface of the reflective film of the transparent substrate,
Wherein the additive contains at least one selected from the group consisting of an organic polymer, a metal oxide, a metal hydroxide, an organic metal compound, and a silicone oil. 18. The method of claim 17,
A protective film is formed by applying a composition for a protective film containing a binder on a reflective film after forming a reflective film and before forming a light emitting layer by a wet coating method and then baking or curing it to form a protective film, Way.

Images