JPH08167475A - Laminate body for electroluminescnce element sealing and electrolumescence element sealing structure - Google Patents

Abstract

PURPOSE: To obtain a laminate body for electroluminescence(EL) sealing by forming a thin film layer of a silicon oxide system on one side or both sides of a plastic film and adding a steam barrier property thereon. CONSTITUTION: On one side or both sides of a plastic film, a thin film layer having a silicon oxide as a necessary component and including one sort or two or more sorts of content selected from a metal fluoride and a magnesium oxide families thereto is formed by means of vacuum thin film forming technology. Furthermore, by laminating a thermal fusing type plastic through an adhesive, a laminate body for EL element sealing can be obtained. By superposing two sheets of thermal fusing type plastics of the laminate body and providing an EL element between them, an EL element sealing structure can be obtained. In such a way, a laminate body to seal and EL element to which a gas barrier property with almost no humidity relaying property, a steam barrier property and a high transparent property are added and an EL sealing structure with the same property can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate for sealing an electroluminescence (hereinafter referred to as EL) element and an EL element sealing structure, particularly an organic EL element, among display materials constituting a flat display. Regarding the structure.

[0002]

2. Description of the Related Art Liquid crystal, plasma display, EL, fluorescent display tube,
Various displays called flat displays such as light emitting diodes have been put into practical use. EL of this
Are liquid crystal display devices, clocks, backlights for measuring instruments, display monitors and light sources for control / measurement equipment, OA equipment, or mobile equipment such as automobiles, static elimination light sources for copying machines, various light sources for interior and exterior decoration, It has been put to practical use or developed as a safety light for indoors and at night, a light source for traffic signs, etc., and has received particular attention. The EL element includes an inorganic EL element whose light emitting substance is an inorganic compound and an organic EL element composed of an organic compound thin film. Among them, the light source part of the inorganic EL element is composed of a light emitting substance such as zinc sulfide, and the light emitting function of the light emitting substance itself is deteriorated by moisture. In the organic EL element, the organic thin film is also affected by moisture, but at the same time, the metal used as the cathode is oxidized by moisture and the interface with the organic layer is peeled off or becomes an oxide, resulting in a decrease in conductivity. Therefore, the light emitting function is significantly reduced. Therefore, the EL element light source section is sealed with a heat-sealing plastic having high moisture resistance such as a fluorine film. However, since the fluorine film has very poor productivity, the price thereof is high, which is one of the factors that prevent the spread of EL. Further, in order to protect the EL element light source part, high moisture resistance is required, and since it is necessary to thicken the fluorine film, the transparency (light transmittance) of the film itself is lowered, and E
There is a drawback that the light emitting capability of the light source of the L element is not sufficiently exhibited.

It is conceivable that a laminate obtained by laminating a heat-fusible plastic on a vapor-deposited film of silicon oxide alone via an adhesive is used as a sealing material for an EL element. Since a single vapor deposition film lacks moisture resistance, it is necessary to stack two or more sheets. However, the vapor-deposited film of silicon oxide alone has a dark brown color, and the brown color becomes darker by stacking two or more layers. The light emitted from the light emitting portion of the EL element passes through the brown laminated body, so that the light amount and the hue are both reduced and changed. Therefore, the laminate using the vapor-deposited film of silicon oxide alone could not be used for EL device encapsulation.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a gas barrier property, a water vapor barrier property, and a moisture barrier property which have almost no humidity dependency.
It is an object of the present invention to provide a laminate for encapsulating an EL element and an EL element encapsulating structure, particularly an organic EL element encapsulating structure, to which high transparency is simultaneously added.

[0005]

According to the present invention, silicon oxide is an essential component on one or both sides of a plastic film (A) by a vacuum thin film forming technique. Forming a thin film layer (B) containing one or more selected components,
It is a laminated body for electroluminescence element encapsulation which is obtained by laminating a heat-fusible plastic (D) via an adhesive (C). The present invention also provides an electroluminescent element-sealed structure comprising two heat-fusible plastics (D) of the above-mentioned laminate, which are superposed on each other, and an electroluminescent element provided between them. The present invention further provides an organic electroluminescence element sealing structure in which an organic electroluminescence element having a light emitting layer or an organic compound thin film layer including a light emitting layer is provided between the anode and the cathode between the laminates.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The plastic film (A) of the present invention includes polyethylene terephthalate, polyethylene-2,6-naphthalate, polycarbonate.
Films of polyester, polysulfone, polyethersulfone, polyetheretherketone, polyphenoxyether, polyarylate, fluororesin, polypropylene and the like can be applied. Since the water vapor barrier property is added by forming the thin film layer (B) on one side or both sides of the plastic film (A), the water vapor barrier property of the plastic film (A) itself may be somewhat poor. Further, any film that can be used for forming a vacuum thin film can be used without particular limitation, and a heat-fixed film such as a biaxially stretched film may be used. It is preferable that nothing is applied to the surface of the plastic film (A), but an easy-adhesion layer for improving the adhesiveness with the thin film layer (B) or an organic barrier layer such as polyvinylidene chloride is provided. It may be provided on one side or both sides. The thickness of the plastic film (A) is preferably 6 to 500 μm, particularly 12 to 50 μm.

The thin film layer (B) has a particularly high water vapor barrier.
It should have good gas-barrier property, low expansion with respect to temperature and humidity, and firmly adhere to the plastic film (A). The thin film layer (B) contains silicon oxide as an essential component, and contains one or more components selected from metal fluorides and magnesium oxides. In any combination, a gas barrier property and a water vapor barrier property can be obtained, but when it is desired to add high light transmittance (transparency) together, a thin film layer composed of a silicon oxide and a metal fluoride ( It is effective to form B). Further, particularly when it is desired to have a high water vapor barrier property, it is effective to form a thin film layer (B) composed of silicon oxide and magnesium oxides.

The silicon oxide constituting the thin film layer (B) is
SiO _x (x = 1 or more, less than 2), and SiO, Si
₂ O ₃ , Si ₃ O _4, etc. are included in this. Above all, Si
When _x of O _x is greater than 1.8 and less than 2.0, the silicon oxide approaches colorless and transparent SiO ₂ .
The light transmittance (transparency) of the obtained thin film layer (B) becomes high. On the other hand, if _x of SiO _x is 1.8 or less, the silicon oxide will be slightly brown, and if _x of SiO x is 1.5 or less, it will be completely brown.

Examples of the metal fluoride constituting the thin film layer (B) include fluorides of alkaline earth metals, fluorides of alkali metals, and aluminum fluoride. Specifically, magnesium fluoride, calcium fluoride, strontium fluoride, barium fluoride, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride,
Examples include cesium fluoride and francium fluoride.
Among these, magnesium fluoride, calcium fluoride,
Strontium fluoride and barium fluoride are preferable, and magnesium fluoride and calcium fluoride are particularly excellent. When the metal fluoride is a fluoride of an alkaline earth metal, both high barrier property and high transparency are preferable, which is preferable. The alkali metal fluoride has the same transparency as that of the alkaline earth metal fluoride, but the barrier property is slightly inferior.

Magnesium oxides constituting the thin film layer (B) include magnesium oxide, a co-oxide of magnesium oxide and silicon dioxide (a co-oxide called forsterite or steatite), and magnesium oxide. A complex compound with a metal fluoride may be mentioned. Thin film layer (B)
The compositional ratio of the silicon oxide: metal fluoride or magnesium oxides constituting the above is 98 to 80 mol%: 2 to 20
Mol% range, especially 95-90 mol%: 5-10 mol%
The range of is desirable. When the thin film layer (B) is composed of silicon oxide, metal fluoride and magnesium oxide, the composition ratio of silicon oxide: metal fluoride: magnesium oxide is 97.5-80 mol. %: 2-19.
5 mol%: in the range of 0.5-18 mol%, especially 93-88
The range of mol%: 5-10 mol%: 2-17 mol% is desirable.

The raw material for the thin film layer (B) may be an inorganic compound such as a metal oxide, a metal fluoride, a metal, an organometallic compound, or an organic compound, either alone or as a mixture, but particularly silicon oxide and metal. A thin film layer (B) may be directly formed on a plastic film by vacuum evaporation or the like using a mixture of fluorides or a mixture of silicon oxide, metal fluoride and a co-oxide of silicon dioxide and magnesium oxide as a raw material. desirable. The composition ratio of the raw materials is such that when silicon oxide and metal fluoride are used, silicon oxide: metal fluoride = 9.
8-70 mol%: in the range of 2-30 mol%, especially 95-8
5 mol%: The range of 5 to 15 mol% is desirable.

When silicon oxides and magnesium oxides are used, silicon oxide: magnesium oxides = 99.5 to 70 mol%: 0.5 to 30 mol%, particularly 99. The range of 5 to 90 mol%: 0.5 to 10 mol% is desirable. Furthermore, when silicon oxide, metal fluoride and magnesium oxide are used, silicon oxide: metal fluoride: magnesium oxide = 97.5
-70 mol%: 2-29.5 mol%: 0.5-28 mol%, especially 95-90 mol%: 4.5-9.5 mol%: 0.5-5.5 mol% Range is desirable.

Examples of the silicon oxide used as a raw material include a mixture of silicon and silicon dioxide, a simple substance of silicon monoxide, and a mixture of silicon, silicon dioxide and silicon monoxide. Silicon (Si) and silicon dioxide (SiO)
_When the mixture of ₂ ) is used, its composition ratio is basically preferably equimolar, but Si: SiO ₂ = 40 to 60 mol%: 60 to 40 mol%. When the silicon oxide used as a raw material is a mixture of Si, SiO, and SiO ₂ , the molar ratio of Si: SiO ₂ may be approximately equal, and the ratio of (Si + SiO ₂ ): SiO is not particularly limited.

The vacuum thin film forming technique for forming the thin film layer (B) on the plastic film (A) may be either a continuous winding method or a single-wafer method, and the forming method may be vacuum vapor deposition or ion plating. , Sputtering, etc. can be used. Furthermore, the heating method for vacuum evaporation is not particularly limited as long as it does not generate evaporation droplets called splash during the evaporation or is small enough to be removed without trouble, and high frequency induction heating, resistance heating, electron beam heating A known heating method such as the above can be used. When a large amount of vapor deposition droplets are generated, the droplets remain as foreign matter on the vapor deposition film, and when the EL element sealing structure is manufactured, the foreign matter becomes black spots, and the EL element sealing structure itself becomes defective.

A general crucible system may be used as an evaporation source for vacuum deposition, but it is disclosed in Japanese Patent Laid-Open Nos. 1-252786 and 2-277774, in which substances having different sublimation points and melting points can always be uniformly vacuum-deposited. A method of continuously supplying and discharging the described evaporation raw material can also be used. When the thin film layer (B) is formed on the plastic film (A), the composition of the raw material may be directly reflected on the composition of the thin film layer (B) by a method such as vacuum deposition, but it may be 2
The thin film layer (B) may be formed while reacting one or more raw materials.

As the method for forming the thin film layer (B) by reactive vapor deposition, vacuum deposition is carried out while oxidizing or fluorinating a metal or a compound containing a metal such as an organic metal oxide, or a metal fluoride is deposited on a plastic film. There may be mentioned a method of performing vapor deposition and then subjecting the deposited layer to an oxidation treatment in a subsequent step. The method of oxidation treatment is not particularly limited as long as it is a method of performing treatment within the usable temperature range of the plastic film, and an oxygen gas introduction method during vapor deposition, a discharge treatment method, an oxygen plasma method,
A thermal oxidation method etc. are mentioned. The thickness of the thin film layer (B) is selected according to the plastic film (A) to be used, but is 5 to 200 nm, particularly 10 to 100 nm per one side.
Is desirable. Further, the thin film layer (B) may have a laminated structure of two or more layers, and at that time, different kinds of metal fluorides and magnesium oxides may be laminated.

The adhesive (C) is not particularly limited,
Urethane adhesives, epoxy amine adhesives, epoxy adhesives, acrylic adhesives, cyanoacrylate adhesives, urethane anchor coating agents, alkyl titanate anchor coating agents, polyethyleneimine anchor coating agents, butadiene adhesives Anchor coat agents are mentioned, and any of organic solvent type, aqueous type and solventless type may be used. The adhesive (C) preferably contains a silane coupler such as epoxysilane or aminosilane as an adhesion aid. There is no limitation on the coating amount of the adhesive (C). However, when the EL sealing structure is always used outdoors, an adhesive having high weather resistance must be used.

The heat-fusible plastic (D) is not limited as long as it has heat-fusible property (heat-sealing property). Polyolefin such as polyethylene and polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer. Films of polymers, ionomers, polyvinyl chloride, polyvinylidene chloride, polyurethane, fluororesins, polyacrylonitrile, polystyrene, polyethylene terephthalate, etc. can be applied. Examples of the method of laminating the heat-fusible plastic (D) include a method of laminating a film in advance such as dry lamination, and a method of laminating a resin to form a film such as extrusion laminating.

To obtain an EL device sealing structure, two EL device sealing laminates of the present invention (basic structure: A / B / C /
The heat-fusible plastic (D) of D) is heat-welded so that the two parts face each other. At that time, the EL element is sandwiched between the two laminated bodies (basic configuration: A / B / C / D / EL element / D /
C / B / A). The heat fusion method is not particularly limited, and generally heat lamination or the like can be used, but lamination using an adhesive may also be used. At this time, the area of the EL element sealing laminate is larger than the area of the EL element, and the four areas are heat-sealed due to the difference between the two areas. If the four sides cannot be completely heat-sealed, the EL element protrudes from the EL element sealing laminate and becomes meaningless as a sealing material.

The basic structure of the EL element encapsulating laminate of the present invention is A / B / C / D, but if it is desired to further improve the water vapor barrier property, A / B / C / A / B / C is used. / D, A /
Stack two vapor-deposited films like B / C / B / A / C / D or 3 vapor-deposited films like A / B / C / A / B / C / A / B / C / D May be stacked.

The inorganic EL element used in the EL element sealing structure of the present invention comprises barium titanate or yttrium oxide on a transparent electrode layer using a conductive oxide such as ITO or a metal thin film such as gold. An insulating layer using a dielectric such as, and a light emitting layer containing a phosphor such as zinc sulfide added with manganese or rare earth fluoride, calcium sulfide, strontium sulfide, etc. are formed in this order, and after providing an insulating layer if necessary The back electrode is made of aluminum, carbon, or the like, but is not limited thereto. A moisture absorption layer or the like may be provided in the element, but is not particularly limited.

The organic EL element used in the EL element sealing structure of the present invention is an element in which a single-layer or multi-layer organic thin film is formed between an anode and a cathode. In the case of a single-layer device, only the light emitting layer is provided between the anode and the cathode. . The multi-layer type device includes (anode / hole injection layer / light emitting layer / cathode), (anode / light emitting layer / electron injection layer / cathode), (anode / hole injection layer / light emitting layer / electron injection layer / cathode) It is composed of either layer.
When the organic EL element has a multi-layered structure, it is possible to efficiently cause recombination of holes and electrons in the light emitting layer, and further, it is possible to prevent reduction in brightness and life due to quenching. .

In the organic EL device, it is desirable that at least one of the electrodes is sufficiently transparent in the emission wavelength region of the device in order to emit light efficiently. It is also desirable that the substrate is transparent. In an organic EL element, the anode is usually a transparent electrode, but it is also possible to use only the cathode or both the anode and the cathode as transparent electrodes. The substrate has mechanical and thermal strength and is not limited as long as it is transparent, but examples thereof include a transparent resin such as a glass plate, a polyethylene plate, a polyether sulfone plate, and a polypropylene plate. .

The conductive material used for the anode of the organic EL element is preferably one having a work function larger than 4.0 eV, such as carbon, aluminum, vanadium, iron, cobalt, nickel, tungsten, silver, gold, Platinum, palladium and alloys thereof, ITO substrates, metal oxides such as tin oxide and indium oxide used for NESA substrates, and organic conductive resins such as polythiophene and polypyrrole are used, but are not limited to these. is not.
The anode may be formed with a layered structure of two or more layers if necessary. The transparent electrode is set using the above-mentioned conductive material so as to ensure a predetermined translucency by a method such as vapor deposition or sputtering. The total light transmittance of the substrate and the anode is preferably 10% or more.

The hole injecting material used for the hole injecting layer of the organic EL device has a capability of efficiently injecting holes from the anode and transporting the holes, and has a capability of transporting holes, and is superior to the light emitting layer or the light emitting material in the light emitting layer. And a compound having an excellent hole injection effect and an excellent thin film forming ability. Specifically, phthalocyanine compounds, naphthalocyanine compounds, porphyrin compounds, oxadiazole, triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone, tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, poly Aryl alkanes, stilbenes, butadienes, benzidine-type triphenylamines, styrylamine-type triphenylamines, diamine-type triphenylamines, and the like, and their derivatives, and polymer materials such as polyvinylcarbazole, polysilane, and conductive polymers. However, it is not limited thereto.

In the organic EL device, a more effective hole injection material is an aromatic tertiary amine derivative or a phthalocyanine derivative. Specifically, as the aromatic tertiary amine derivative, triphenylamine, tritolylamine, tolyldiphenylamine, N, N'-diphenyl-
N, N'-di (3-methylphenyl) -1,1'-biphenyl-4,4'-diamine, N, N'-diphenyl-
N, N'-di (2,4-dimethylphenyl) -1,1 '
-Biphenyl-4,4'-diamine, N, N, N'N '
-Tetra (4-methylphenyl) -1,1'-di (3-
Methylphenyl) -4,4'-diamine, N, N, N '
N'-tetra (4-methylphenyl) -1,3-phenylenediamine, N, N'-diphenyl-N, N'-dinaphthyl-1,1'-biphenyl-4,4'-diamine,
N, N'-di (4-methylphenyl) -N, N'-di (4-n-butylphenyl) -phenanthrene-9,1
Examples thereof include 0-diamine, 1,1-bis (4-di (4-methylphenyl) aminophenyl) cyclohexane, and oligomers or polymers having an aromatic tertiary amine skeleton, but are not limited thereto. Not a thing. As the phthalocyanine (Pc) derivative, H ₂ P
c, CuPc, CoPc, NiPc, ZnPc, PdP
c, FePc, MnPc, ClAlPc, ClGaP
c, ClInPc, ClSnPc, Cl ₂ SiPc,
(HO) AlPc, (HO) GaPc, VOPc, Ti
There are phthalocyanine derivatives such as OPc, MoOPc, GaPc-O-GaPc and naphthalocyanine derivatives, but not limited to these.

The light emitting layer of the organic EL element comprises a light emitting material and a doping material added to the light emitting material as necessary. The light-emitting material has excellent thin film forming ability, and in the thin film state, holes and electrons injected from the electrode, the hole injection layer, and the electron injection layer are efficiently recombined in the light emitting layer, and excited by the energy generated at that time. It is a material with high emission intensity, which is the energy emission when returning from the excited state to the ground state. Further, the doping material is a material added to the light emitting layer when the brightness from the light emitting layer is improved or the emission color is changed. The doping material has only to exhibit the required characteristics in a state of being added to the light emitting layer, has a poor thin film forming ability, and does not have to emit light in a single thin film state. Specific examples of the light emitting material or the doping material include anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, coumarin,
Oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, quinoline metal complex, aminoquinoline metal complex, benzoquinoline metal complex, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine, merocyanine , Imidazole chelated oxinoid compounds, quinacridone, rubrene and the like, and derivatives thereof, but are not limited thereto.

The electron injection material used for the electron injection layer of the organic EL device has an ability to transport electrons, has an excellent electron injection effect on the light emitting layer or the light emitting material, and has an excellent thin film forming ability. Compounds. For example, there are fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxadiazole, thiadiazole, tetrazole, perylene tetracarboxylic acid, fluorenylidene methane, anthraquinodimethane, anthrone and their derivatives. It is not limited to.

In the organic EL device, a more effective electron injection material is a metal complex compound or a nitrogen-containing five-membered ring derivative. Specifically, as the metal complex compound, 8
-Lithium hydroxyquinolinato, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato) aluminum, Tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, bis (10-hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinate) Zinc, bis (2-methyl-8-
Quinolinato) chlorogallium, bis (2-methyl-8)
-Quinolinato) (o-cresolato) gallium, bis (2-methyl-8-quinolinato) (1-naphtholato) aluminum, bis (2-methyl-8-quinolinato) (2-naphtholato) gallium, and the like. It is not limited. Further, as the nitrogen-containing five-membered derivative, an oxazole, thiazole, oxadiazole, thiadiazole or triazole derivative is preferable. Specifically, 2,5-bis (1-phenyl)-
1,3,4-oxazole, dimethyl POPOP, 2,
5-bis (1-phenyl) -1,3,4-thiazole,
2,5-bis (1-phenyl) -1,3,4-oxadiazole, 2- (4'-tert-butylphenyl)-
5- (4 "-biphenyl) 1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1,3,4-oxadiazole, 1,4-bis [2- (5- Phenyloxadiazolyl)] benzene, 1,4-bis [2- (5-
Phenyloxadiazolyl) -4-tert-butylbenzene], 2- (4'-tert-butylphenyl)-
5- (4 "-biphenyl) -1,3,4-thiadiazole, 2,5-bis (1-naphthyl) -1,3,4-thiadiazole, 1,4-bis [2- (5-phenylthiadiazo] Ryl)] benzene, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-
Triazole, 2,5-bis (1-naphthyl) -1,
Examples thereof include 3,4-triazole and 1,4-bis [2- (5-phenyltriazolyl)] benzene, but are not limited thereto.

In each of the hole injecting layer, the light emitting layer, and the electron injecting layer in the organic EL device, a hole injecting material, a light emitting material, and a doping material are introduced so that holes or electrons are efficiently injected from the electrodes and transported in the layers. Two or more kinds of materials or electron injection materials may be mixed and used in the same layer, and the hole injection layer, the light emitting layer, and the electron injection layer may each be formed of a layer structure of two or more layers. . A hole injection material or an electron injection material may be added to the light emitting layer in order to efficiently transport holes injected from the anode or electrons injected from the cathode to the light emitting material or the doping material. Further, an electron accepting substance may be added to the hole injection layer and an electron donating substance may be added to the electron injection material to sensitize.

The hole injecting layer, the light emitting layer, and the electron injecting layer in the organic EL device according to the present invention are each formed by a dry film forming method such as resistance heating vapor deposition, electron beam vapor deposition, sputtering, ion plating, chemical reaction vapor deposition, or spin. Any of wet film forming methods such as coating and dipping can be applied. The film thickness is not particularly limited, but each layer needs to be set to an appropriate film thickness. If the film thickness is too thick, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. If the film thickness is too thin, pinholes or the like are generated in the thin film, and sufficient light emission brightness cannot be obtained even when an electric field is applied. Normal film thickness is 5nm to 10μ
A range of m is suitable, but a range of 10 nm to 0.2 μm is more preferable.

In the case of the wet film forming method, the material forming each layer is dissolved or dispersed in an appropriate solvent such as chloroform, tetrahydrofuran, dioxane to form a thin film.
The solvent may be any. Further, in any of the thin films, an appropriate resin or additive may be used in order to improve the film forming property and prevent pinholes in the film. Resins that can be used include polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane,
Insulating resin such as polysulfone, polymethylmethacrylate, polymethylacrylate, cellulose, poly-N
-Photoconductive resin such as vinylcarbazole and polysilane,
Examples of the conductive resin include polythiophene and polypyrrole. Examples of the additives include antioxidants, ultraviolet absorbers, plasticizers and the like.

As the conductive material used for the cathode in the organic EL device, those having a work function smaller than 4 eV are preferable, and cesium, rubidium, potassium, sodium, lithium, barium, strontium, calcium, magnesium, Europium, ytterbium, samarium, cerium, erbium, gadolinium, yttrium, neodymium, lanthanum, scandium, and the like, and alloys thereof with metal elements of 4 eV or more are used, but not limited to these. Examples of the film forming method include resistance heating vapor deposition, electron beam vapor deposition, DC sputtering, RF sputtering, and ion plating.

The present invention does not preclude multi-component alloying to improve cathode stability or other properties. Further, the cathode may be composed of two or more layers of metal or alloy as required, and the composition and the component ratio thereof may continuously change between the lower part and the upper part of the layer. Further, an insulating oxide or nitride having a higher barrier property against moisture and oxygen may be formed so as to cover the cathode.

In the organic EL element encapsulation structure obtained by the present invention, in order to further improve the stability against temperature, humidity, atmosphere, etc., another encapsulation film or a different encapsulation film is provided inside or outside the encapsulation structure. It is also possible to use a sealing resin or the like. It is also possible to protect the element by enclosing silicon oil or the like inside the sealing structure. When the encapsulating laminate in the present invention is used in combination with these encapsulating resins or silicone oils, it is preferable that the resin or oil is applied or sealed only on the cathode side opposite to the light emitting surface.

[0036]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to the following examples without departing from the gist thereof. The test method in the examples is as follows. Water vapor barrier property: In accordance with ASTM F 1249,
"PERMATRAN-" manufactured by Modern Controls, Inc.
Water vapor transmission rate was measured using "W-TWIN". The smaller this value, the better the water vapor barrier property. Transparency: spectrophotometer ("U-best3" manufactured by JASCO Corporation)
0 ") was used, and the transmittance at 400 nm was measured using air as a reference. The larger this value, the better the transparency. EL element encapsulation structure test: Inorganic and organic EL element encapsulation structures were exposed in an environment of 40 ° C. and 90% RH for 10,000 hours. After that, both EL elements were caused to emit light, and it was evaluated whether the EL elements were damaged. The inorganic EL element was evaluated by visual observation, and the organic EL element was evaluated by the degree of decrease in emission luminance and visual observation.

Example 1 A continuous winding type resistance heating type vacuum vapor deposition system for continuously supplying and discharging an evaporation raw material described in JP-A-1-252786 was used, and a 25 μm thick polyester film was used. A mixture of silicon, silicon dioxide and magnesium fluoride (mixing ratio 46 mol%: 46 mol%: 8 mol%) was vacuum-deposited by heating on one surface of a telsalphone (PES) film (thickness of thin film layer is about 60 n.
m). The obtained vapor-deposited film was dry laminated using a 25 μm fluororesin film (“FEP” manufactured by Daikin Co., Ltd.) and an adhesive (“AD76P1 / CAT-10” manufactured by Toyo Morton Co., Ltd.), and a laminated body for EL device sealing. Got

Example 2 Using the same vacuum vapor deposition apparatus as in Example 1, one side of a polyethylene terephthalate (PET) film having a thickness of 12 μm was coated with silicon monoxide and a co-oxide of silicon dioxide and magnesium oxide. A mixture of (forsterite: SiO ₂ .2MgO) (mixing ratio 90 mol%: 10 mol%) was vacuum-deposited by heating (thickness of thin film layer was about 60 nm). The obtained vapor-deposited film was dry-laminated using a linear low-density polyethylene (L-LDPE) having a thickness of 40 μm and an adhesive (“AD585 / CAT-10” manufactured by Toyo Morton Co., Ltd.) to obtain a laminate for sealing an EL device. Obtained.

[Embodiment 3] A vacuum deposition apparatus similar to that of Embodiment 1
With a thickness of 25 μm polyethylene terephthalate
On one side of the (PET) film, silicon, silicon dioxide,
Magnesium fluoride and silicon dioxide and magnesium acid
Compound Cooxide (Steatite: 2SiO ₂・ 2Mg
O) mixture (mixing ratio 40 mol%: 40 mol%: 10 m
(% By mole: 10 mol%) was vacuum-deposited by heating (thickness of thin film layer).
Is about 60 nm). The obtained vapor-deposited film was
Linear low density polyethylene (L-LDPE) and Example 2
Dry laminate in the same manner, and EL element sealing laminate
Got

[Embodiment 4] The same vacuum vapor deposition apparatus as in the embodiment is used except that the heating evaporation source is switched to the electron beam type.
12 μm thick polyethylene terephthalate (PET)
On one side of the film, a mixture of silicon, silicon dioxide and calcium fluoride (mixing ratio 45 mol%: 45 mol%:
10 mol%) was vacuum-deposited by heating (thickness of thin film layer is about 6).
0 nm). The obtained two vapor-deposited films and 40 μm polypropylene (CPP) were dry-laminated using an adhesive (“AD590 / CAT-55” manufactured by Toyo Morton Co., Ltd.) (structure: PET / thin film layer / adhesive / PET). / Thin film layer / adhesive / CPP) to obtain a laminate for EL device sealing.

Comparative Example 1 Polyether sulfone (P
An EL device encapsulating laminate was obtained in the same manner as in Example 1 except that the ES film was not vacuum-deposited (no thin film layer was formed). [Comparative Example 2] An EL device sealing laminate was obtained in the same manner as in Example 2 except that the polyethylene terephthalate (PET) film was not vacuum-deposited (no thin film layer was formed). [Comparative Example 3] An EL device sealing laminate was obtained in the same manner as in Example 2 except that only silicon monoxide was used as the vapor deposition material.

The EL element sealing laminates obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were tested for water vapor barrier property and transparency. Further, an EL element sealing structure is manufactured by thermocompression bonding using the EL element sealing laminates obtained in Examples and Comparative Examples, and inorganic and organic EL elements,
An EL element sealing structure test was conducted. The results are shown in Table 1.
The inorganic EL elements used in this example and the comparative example are IT
An insulating layer made of barium titanate and a light emitting layer made of zinc sulfide: manganese were formed on the O electrode, and aluminum was formed thereon as a back electrode. The organic EL device used was prepared as follows.
On the washed glass plate with an ITO electrode, oligo (p-tolylimino-1,4-phenylene-1,1-cyclohexylene-1,4-phenylene) was vacuum-deposited to give a film thickness of 5
A 0 nm hole injection layer was obtained. Then, a tris (8-hydroxyquinoline) aluminum complex was used as a light emitting material to perform vacuum evaporation to form a light emitting layer having a film thickness of 50 nm. On top of that, an alloy of Mg: Ag = 10: 1 by co-evaporation has a film thickness of
A cathode having a film thickness of 00 nm was formed. The hole injection layer, the light emitting layer and the cathode were vapor-deposited in a vacuum of 10 ⁻⁶ Torr and at a substrate temperature of room temperature.

[0043]

[Table 1]

Example 5 H ₂ Pc was vacuum-deposited on a washed glass plate with an ITO electrode to obtain a first hole injection layer having a thickness of 10 nm. Furthermore, 1,1-bis (4-di-
p-Tolylaminophenyl) cyclohexane was vacuum-deposited to obtain a second hole injection layer having a thickness of 40 nm. Then
A tris (8-hydroxyquinoline) aluminum complex was used as a light emitting material to perform vacuum deposition to form a light emitting layer having a film thickness of 50 nm. On top of that, Mg: In = 10: 1 by co-evaporation
A cathode having a thickness of 200 nm was formed from the alloy of. The hole injection layer, the light emitting layer and the cathode were vapor-deposited in a vacuum of 10 ⁻⁶ Torr and at a substrate temperature of room temperature. An organic EL element encapsulation structure was manufactured by thermocompression bonding using the organic EL element thus prepared and the laminate of Example 2. This organic EL element encapsulation structure is placed in an environment of 40 ° C. and 90% RH for 1
The results of light emission after exposure for 0000 hours are shown in Table 2.

Example 6 N, N'-diphenyl-N, N'-di (3-
Methylphenyl) -1,1'-biphenyl-4,4'-
Diamine was vacuum-deposited to obtain a hole injection layer having a film thickness of 50 nm. Then, quinacridone was co-evaporated at a ratio of 1 mol% with respect to the tris (8-hydroxyquinoline) aluminum complex to form a light emitting layer having a film thickness of 50 nm. On top of that, an alloy of Al: Li = 3: 2 was formed by co-evaporation to a film thickness of 20.
A cathode having a film thickness of 0 nm was formed. The hole injection layer, the light emitting layer and the cathode were vapor-deposited in a vacuum of 10 ⁻⁶ Torr and at a substrate temperature of room temperature. Organic EL created in this way
The element and the laminate of Example 2 were used for thermocompression bonding to produce organic E
An L element sealing structure was manufactured. The organic EL device sealing structure is exposed to light in the environment of 40 ° C. and 90% RH for 10,000 hours, and then light is emitted.

Example 7 Oligo (p-tolylimino-1,4-phenylene-1,1-cyclohexylene-1,4-phenylene) was vacuum-deposited on a washed glass plate with an ITO electrode to form a film. A hole injection layer having a thickness of 50 nm was obtained. Then bis (2-methyl-8-quinolinate)
A (1-naphtholato) gallium complex was used as a light emitting material to perform vacuum deposition to form a light emitting layer having a film thickness of 50 nm. On top of that, an alloy of Mg: Ag = 10: 1 by co-evaporation has a film thickness of 2
A cathode having a film thickness of 00 nm was formed. The hole injection layer, the light emitting layer and the cathode were vapor-deposited in a vacuum of 10 ⁻⁶ Torr and at a substrate temperature of room temperature. Organic E created in this way
An organic EL element sealing structure was manufactured by thermocompression bonding using the L element and the laminate of Example 2. The organic EL device sealing structure is exposed to light in the environment of 40 ° C. and 90% RH for 10,000 hours, and then light is emitted.

Example 8 Oligo (p-tolylimino-1,4-phenylene-1,1-cyclohexylene-1,4-phenylene) was vacuum-deposited on a washed glass plate with an ITO electrode to form a film. A hole injection layer having a thickness of 40 nm was obtained. Then, N, N, N ', N'-tetra (4- (2-
Phenyl-2-propyl) phenyl) anthracene-
Vacuum emission was performed using 9,10-diamine as a light emitting material to form a light emitting layer having a film thickness of 30 nm. Further, 2,5-bis (1-naphthyl) -1,3,4-oxadiazole was vacuum-deposited to form an electron injection layer having a film thickness of 30 nm. A cathode having a thickness of 200 nm was formed on the cathode by co-evaporation using an alloy of Mg: Ag = 10: 1. The organic layers and the cathode were vapor-deposited under the conditions of a substrate temperature of room temperature in a vacuum of 10 ⁻⁶ Torr. An organic EL element encapsulation structure was manufactured by thermocompression bonding using the organic EL element thus prepared and the laminate of Example 2. The organic EL device sealing structure is exposed to light in the environment of 40 ° C. and 90% RH for 10,000 hours, and then light is emitted.

[0048]

[Table 2]

[0049]

According to the present invention, an EL device encapsulating laminate having a high degree of colorless transparency and a high degree of water vapor barrier property can be obtained without using an expensive thick fluorine film. Furthermore, by sealing an EL element, particularly an organic EL element, with this laminated body, it has become possible to obtain a stable EL element encapsulation structure that is free from alteration over a long period of time.

Claims (5)

[Claims] 1. A plastic film (A) having, on one or both sides thereof, a silicon oxide as an essential component by a vacuum thin film forming technique, and one or more selected from metal fluorides and magnesium oxides. A laminated body for encapsulating an electroluminescence device, which comprises forming a thin film layer (B) containing a component, and further laminating a heat-fusible plastic (D) via an adhesive (C). 2. The metal fluoride constituting the thin film layer (B) is
The electroluminescent element sealing laminate according to claim 1, which is one or more selected from magnesium fluoride, calcium fluoride, strontium fluoride and barium fluoride. 3. The magnesium oxide constituting the thin film layer (B) is one or two selected from magnesium oxide, a co-oxide of magnesium oxide and silicon dioxide, and a complex compound of magnesium oxide and metal fluoride. The laminated body for encapsulating an electroluminescence element according to claim 1 or 2, which comprises at least one kind. 4. An electroluminescent element encapsulation structure comprising: two heat-fusible plastics (D) of the laminate according to claim 1 being superposed on each other, and an electroluminescent element provided therebetween. 5. An electroluminescent element sealing structure, wherein the electroluminescent element according to claim 4 is an organic electroluminescent element including a light emitting layer or an organic compound thin film layer including a light emitting layer between an anode and a cathode.