JP2009081123A - Top emission type organic el element, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a top emission type organic EL element wherein warps are reduced. <P>SOLUTION: In this top emission type organic EL element having at least a pair of electrode layers 2, and an organic compound layer 3 on one side of a non-translucent base material 1, a gas barrier layer 5 is laminated on the electrode remote from the non-translucent base material through an adhesive layer or a smoothing layer 4, and an anti-curl layer 6 is provided on the other side of the non-translucent base material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a top emission type organic EL device and a manufacturing method thereof.

  Conventionally, prevention of the warp accompanying the thinning of an organic EL element has been studied. For example, Patent Document 1 discloses a bottom emission type organic EL element in which an anti-curl layer (warp prevention layer) is provided on the side opposite to the organic compound layer of a transparent substrate. .

JP 2003-317937 A

  Here, as a result of investigations by the present inventors, it was found that the warpage of the organic EL element is more remarkable in the top emission type organic EL element than in the bottom emission type organic EL element. The object of the present invention is to provide a top emission type organic EL device with reduced warpage.

When the present inventors examined the reason why the warpage of the top emission type organic EL element is remarkable, the bottom emission type organic EL element uses a transparent substrate such as glass or transparent plastic as the substrate of the organic EL element, Since the transparent substrate side is attached as a backlight of a liquid crystal display device or the like, it was found that the influence of warping was small. That is, in the top emission type organic EL element, since there is no such sticking, the influence of the warp becomes more serious.
The present invention has been accomplished by finding the above-mentioned problems. Specifically, the present invention has been accomplished by the following means.
(1) At least one pair of electrode layers on one surface of the non-translucent base material, an organic compound layer provided between the electrode layers, and an electrode far from the non-translucent base material An organic EL device having a gas barrier layer laminated thereon via an adhesive layer or a smoothing layer, wherein an anti-curl layer is provided on the other surface of the non-translucent substrate. Emission type organic EL element.
(2) The third root of the volume shrinkage ratio at the time of curing of the adhesive layer or the smoothing layer, the elastic modulus, and the layer thickness (unit: μm) are x1, y1, and z1 in this order, and the anti-curl layer is cured. (X2) × (x1) × (y1) × (z1) (x2) × (z1) where the third root of the volumetric shrinkage, the elastic modulus, and the layer thickness (unit: μm) are x2, y2, and z2, respectively. The top emission type organic EL device of (1), wherein the ratio to y2) × (z2) is 0.1 to 10.
(3) The top emission type organic EL device according to (2), wherein a ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) is 0.3 to 3.
(4) The top emission type organic EL device according to any one of (1) to (3), wherein the adhesive layer contains a polymer of a polymerizable (meth) acrylate monomer as a main component.
(5) The top emission type organic EL device according to any one of (1) to (4), wherein the decrease in the elastic modulus of the anticurl layer when it contains water is 30% or less.
(6) The method for producing an organic EL element according to any one of (1) to (5), wherein an anti-curl layer is provided by curling a non-light-transmitting substrate in advance to the anti-curl layer side. Then, the manufacturing method of an organic EL element which provides a gas barrier film through an adhesive layer or a smoothing layer.

 By this invention, the curvature in a top emission type organic EL element was reduced, and the destruction of the organic EL element by the curvature was reduced.

  Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value. Moreover, the organic EL element in this specification means an organic electroluminescence element.

First, a typical top emission type organic EL device will be described with reference to FIG. 1, but it goes without saying that the present invention is not limited to this.
The top emission type organic EL device of the present invention includes a non-translucent substrate 1, a pair of electrodes 2 provided on the non-translucent substrate, an organic compound layer 3 provided between the electrodes, A gas barrier layer 5 provided on an electrode via an adhesive layer or a smoothing layer (hereinafter sometimes abbreviated as “adhesive layer or the like”) 4 on the side opposite to the non-translucent substrate; It has the anti-curl layer 6 provided on the opposite side to an electrode on a translucent base material. Here, the anti-curl layer counteracts the warp by providing a stress layer that antagonizes the tensile stress of the adhesive layer on the surface on the opposite side.
In the present invention, the third root of the volumetric shrinkage ratio at the time of curing of the adhesive layer, the elastic modulus, and the layer thickness (unit: μm) are sequentially set to x1, y1, and z1, and the volume at the time of curing the anti-curl layer. (X1) × (y1) × (z1) (x2) × (y2) where the third root of the shrinkage, the elastic modulus, and the layer thickness (unit: μm) are x2, y2, and z2 in this order. The ratio to x (z2) is 0.1 to 10. In the case of a top emission type organic EL element, when these ratios are less than 0.1 or greater than 10, the balance is deteriorated and warpage cannot be suppressed.
Here, the volume shrinkage ratio at the time of curing of the adhesive layer is the difference between the volume of the adhesive such as the adhesive layer before curing and the volume of the adhesive such as the adhesive layer after curing. The volume shrinkage ratio at the time of curing of the anti-curl layer is a value obtained by dividing the volume of the agent by the volume of the agent. The value divided by the volume of the agent. This value can be actually measured, but since it is almost constant depending on the material, a literature value can be used. As the literature value, use the values described in page 100 of “UV curing curing failure / inhibition factors and countermeasures” edited by the Technical Information Association, FIG. 6, photocuring technology data book, material edition, and Technonet Corporation. it can. Since the values vary depending on the literature, it is preferable to refer to the values of x1 and x2 from the same literature.
When the substrate is curled in the anti-curl direction and another film is bonded, the value of the third root of the volume shrinkage is the reciprocal of the radius of curvature of the previously curled substrate (the radius of the substrate curl) is Acm. When the thickness of the adhesive for film bonding is Bcm and the thickness of the film for bonding is Ccm, it can be obtained by 1- (A / (ABC-2)). This value does not need to obtain the cube root, and the value of the equation can be used as it is.
Even if the elastic modulus is the same material, the elastic modulus changes depending on the curing conditions and the film thickness. Therefore, the elastic modulus can be obtained as the microhardness by directly measuring the layer with a commercially available microhardness meter. The values of y1 and y2 are preferably measured using the same measuring device and measurement conditions. In addition, when the base material is curled in the anti-curl direction and another film is bonded, the elastic modulus of another film can be separately measured and used.
The layer thickness (unit: μm) is the thickness of the adhesive layer or the like, the anti-curl layer, or the anti-curl laminating film, and can be determined by the theoretical layer thickness when each layer is installed or by direct measurement.
The ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) is preferably 0.3 to 3, more preferably 0.5 to 2, More preferably, it is 0.75 to 1.3.
As a method of setting the ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) within the scope of the present invention, (A) reducing the thickness of the adhesive layer, etc. (B) Decrease the elastic modulus of the adhesive layer, etc. (C) Decrease the cure shrinkage rate of the adhesive layer, etc. (D) Increase the elastic modulus of the anti-curl layer, (E) Increase the cure shrinkage rate of the anti-curl layer, (F) The method of increasing the thickness of the anti-curl layer and (G) adjusting the curl amount when the anti-curl layer is previously curled in a desired direction are used alone or in combination.

Hereinafter, the organic EL device of the present invention will be described in more detail.
(Adhesive layer)
As the adhesive layer in the present invention, a known adhesive layer can be widely employed, and a polymerization-type adhesive layer is preferably employed because a step of removing the solvent is unnecessary.
In the present invention, the adhesive layer can be mainly composed of a polymerized polymerizable (meth) acrylate monomer. Here, “main component” means that the polymer of (meth) acrylate is the first component of the adhesive layer, and usually refers to the component having the largest weight ratio. As the (meth) acrylate monomer in the present invention, commercially available monomers, oligomers, and in some cases, polymers and mixtures thereof can be used.
Since the cure shrinkage is caused by the volume shrinkage of the acrylate group accompanying the cure, the cure shrinkage rate can be reduced by (1) using a monomer having a low acrylate content. In addition, a film having a lower elastic modulus can be produced as (a) the curing rate is slower, (b) the crosslinking point density is lower, and (c) the distance between the crosslinking points is longer.
Epoxy adhesives can also be used.

Further, as the adhesive, an adhesive having a small curing shrinkage can be used. Specifically, a polymer of a compound having an ethylenically unsaturated bond at the terminal or side chain, and / or an epoxy or oxetane is terminal or An adhesive or a pigment mainly composed of a polymer of a compound having a side chain is more preferable. A compound having both a functional group capable of radical polymerization and an ethylenically unsaturated bond and a functional group capable of cationic polymerization in the molecule can also be preferably used. The monomer polymerization method is not particularly limited, but heat polymerization, light (ultraviolet ray, visible light) polymerization, electron beam polymerization, plasma polymerization, or a combination thereof is preferably used. When carrying out heat polymerization, the substrate film needs to have appropriate heat resistance. In this case, at least the Tg (glass transition temperature) of the plastic film needs to be higher than the heating temperature.
When carrying out photopolymerization, a photopolymerization initiator is used in combination. Examples of the photopolymerization initiator include Irgacure series (for example, Irgacure 651, Irgacure 754, Irgacure 184, Irgacure 2959 Irgacure 907, Irgacure 369, Irgacure 379, Irgacure 819, etc., commercially available from Ciba Specialty Chemicals. ), Darocure series (eg, Darocur TPO, Darocur 1173, etc.), Quantacure PDO, Ezacure series (eg, Ezacure TZM, Ezacure TZT, etc.) commercially available from Sartomer. Can be mentioned.
The light to irradiate is usually ultraviolet light from a high pressure mercury lamp or a low pressure mercury lamp. The irradiation energy is preferably 0.5 J / cm ² or more, and more preferably ² J / cm ² or more. Since acrylate and methacrylate are subject to polymerization inhibition by oxygen in the air, it is preferable to lower the oxygen concentration or oxygen partial pressure during polymerization. When the oxygen concentration during polymerization is lowered by the nitrogen substitution method, the oxygen concentration is preferably 2% or less, and more preferably 0.5% or less. When the oxygen partial pressure during polymerization is reduced by the decompression method, the total pressure is preferably 1000 Pa or less, and more preferably 100 Pa or less. Further, it is particularly preferable to perform ultraviolet polymerization by irradiating energy of ² J / cm ² or more under a reduced pressure condition of 100 Pa or less.

 At this time, the polymerization rate of the monomer is preferably 80% or more, more preferably 85% or more, and further preferably 90% or more. The polymerization rate here means the ratio of the reacted polymerizable groups among all the polymerizable groups (acryloyl group and methacryloyl group) in the monomer mixture.

 When the pigment is dispersed in the adhesive of the top emission type element as in the present invention, there is an advantage that the film thickness of the adhesive layer can be kept constant, but the shape, size, addition amount, pigment / adhesion of the pigment is advantageous. Care must be taken in adjusting the refractive index of the agent. If the refractive index of the two is greatly different, the particle shape of the pigment is anisotropic, the particle size is large, or the particle size distribution is wide, light scattering by the adhesive layer becomes remarkable, and the quality of the display image is improved. May be reduced.

  In the present invention, as the adhesive layer, in addition to the adhesive layer provided between the electrode and the gas barrier film, another adhesive layer may be included. In the adhesive layer, in addition to the layer for bonding the sealing film to the organic EL element, a smoothing used for smoothing the surface in the case of providing an encapsulation film on the surface of the organic EL element Also included are those that play a role as stratified layers.

  The volume shrinkage ratio of the adhesive layer in the present invention is preferably 5 to 20%. Moreover, it is preferable that the elasticity modulus of the contact bonding layer in this invention is 0.1-1.0 Gpa. Furthermore, the layer thickness of the adhesive layer in the present invention is preferably 0.1 to 100 μm.

(Anti-curl layer)
The material of the anti-curl layer in the present invention is not particularly defined and can be widely selected from known materials. Here, in the case of the top emission type organic EL device of the present invention, since the anti-curl layer is likely to be used in an exposed state, there is a material whose warpage does not change in a temperature / humidity environment during use or assembly. It is preferable to be selected. The adhesive layer is not affected by environmental humidity because it is located in the cell of the organic EL element, whereas the anti-curl layer is directly affected by environmental humidity because it has a structure in contact with the outside. However, other factors often make it difficult to select such materials. Therefore, in the present invention, in order to prevent the anti-curl layer from greatly expanding / contracting due to temperature and environmental humidity and the elastic modulus from changing greatly, the elastic change rate is also considered, and the above (x1) × (y1) The condition of the ratio of x (z1) to (x2) x (y2) x (z2) is set. Therefore, in the present invention, the material of the anti-curl layer is not limited. In addition to the resin film, it can be widely selected from metal foil, (meth) acrylate monomer cured product, and the like.
When a resin film or metal foil is used as an anti-curl layer, (1) the base material is curled in the anti-curl direction in advance, and (2) the anti-curl of one set of nip rolls to be bonded together. The elastic modulus of the roll to be attached is made higher than the elastic modulus of the other roll. (3) The diameter of the roll on the anti-curl side of one set of nip rolls to be bonded is smaller than the diameter of the other roll. It can be realized by drying or curing the adhesive after bonding by a method such as.
The concept for using a (meth) acrylate monomer cured product is the same as that for the adhesive layer, and any of commercially available monomers and oligomers, and in some cases, polymers and mixtures thereof can be used.
As a material for the anti-curl layer, a material having a thin anti-curl property and a high anti-curl property is required. Therefore, it is preferable to select a material and a process having a large cure shrinkage. That is, (1) use of a monomer having a high acrylate content, and (2) an increase in the polymerization rate can increase the cure shrinkage. In addition, a film having a lower elastic modulus can be produced as (a) the curing rate is faster, (b) the density of crosslinking points is higher, and (c) the distance between crosslinking points is shorter. Specifically, DPHA (diventaerythritol hexaacrylate), PETIA (pentaerythritol triacrylate), NP (neopentyl glycol diacrylate), HD (1,6-hexanediol diacrylate) and the like are preferably employed.

The volume shrinkage of the anti-curl layer in the present invention is preferably 10 to 30%. Moreover, it is preferable that the elasticity modulus of the anti-curl layer in this invention is 0.3-1.0 Gpa. Furthermore, the layer thickness of the anti-curl layer in the present invention is preferably 0.1 to 5 μm.
In the present invention, the decrease in the elastic modulus of the anticurl layer when it contains water is preferably 30% or less, and more preferably 20% or less. Moreover, the time of water content here means the case where it is left to stand for 1 day or more in an environment of 40 ° C. and 90%.

Further, in order to suppress warpage against temperature change, it is preferable to set the difference in the coefficient of thermal expansion between the adhesive layer and the anti-curl layer in the range of 100 to -100 ppm / ° C. For this purpose, it is preferable to use the same material for the adhesive layer and the anti-curl layer. The temperature expansion coefficient here is defined as the average value of the slope of the thermal expansion curve measured between 10 ° C. and 50 ° C.
In the present invention, it is also preferable to curl the anti-curl layer in advance. In this case, the anti-curl layer does not need to be a curable resin layer, and a film such as a metal foil or a plastic film may be bonded.

(Gas barrier layer)
The gas barrier layer of the present invention is composed of a gas barrier film or a gas barrier layer by encapsulation, and has a function of blocking oxygen and moisture in the atmosphere. The gas barrier layer in the present invention has at least one inorganic layer, and is preferably a laminate of at least one organic layer and at least one inorganic layer. Organic layers and inorganic layers are usually laminated alternately. The composition which comprises each layer may be what is called a gradient material layer from which the film thickness direction changes continuously. As an example of the gradient material, an article by Kim et al. “Journal of Vacuum Science and Technology A Vol. 23 p971-977 (2005 American Vacuum Society) Journal of Vacuum Science and Technology A Vol. 23, pages 971-977 , American Vacuum Society) ”.
Although there is no restriction | limiting in particular regarding the number of layers which comprises a cas barrier film, Typically 2-30 layers are preferable, and 2 layers-10 layers are more preferable.

(Gas barrier layer base material)
The gas barrier layer in the present invention may be a so-called gas barrier film having a base film or a so-called encapsulation film in which a gas barrier film is directly laminated on an organic EL element.
A plastic film is preferably used as the base film when the gas barrier layer is a gas barrier film. The plastic film to be used is not particularly limited in material, thickness and the like as long as it can hold a laminate such as an organic layer and an inorganic layer, and can be appropriately selected according to the purpose of use. Specifically, as the plastic film, metal support (aluminum, copper, stainless steel, etc.) polyester resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene resin, transparent fluororesin, polyimide, fluorinated polyimide resin , Polyamide resin, polyamideimide resin, polyetherimide resin, cellulose acylate resin, polyurethane resin, polyetheretherketone resin, polycarbonate resin, alicyclic polyolefin resin, polyarylate resin, polyethersulfone resin, polysulfone resin, cycloolefin Examples thereof include thermoplastic resins such as filn copolymers, fluorene ring-modified polycarbonate resins, alicyclic ring-modified polycarbonate resins, fluorene ring-modified polyester resins, and acryloyl compounds.

  As for the gas barrier film in this invention, it is preferable that a plastic film consists of a raw material which has heat resistance. Specifically, it is preferable that the glass transition temperature (Tg) is 100 ° C. or higher and / or the linear thermal expansion coefficient is 40 ppm / ° C. or lower and is made of a transparent material having high heat resistance. Tg and a linear expansion coefficient can be adjusted with an additive. As such a thermoplastic resin, for example, polyethylene naphthalate (PEN: 120 ° C.), polycarbonate (PC: 140 ° C.), alicyclic polyolefin (for example, ZEONOR 1600: 160 ° C. manufactured by Nippon Zeon Co., Ltd.), polyarylate ( PAr: 210 ° C., polyethersulfone (PES: 220 ° C.), polysulfone (PSF: 190 ° C.), cycloolefin copolymer (COC: Japanese Patent Application Laid-Open No. 2001-150584 compound: 162 ° C.), polyimide (for example, Mitsubishi Gas Chemical) Neoprim: 260 ° C.), fluorene ring-modified polycarbonate (BCF-PC: compound of JP 2000-227603 A: 225 ° C.), alicyclic modified polycarbonate (IP-PC: compound of JP 2000-227603 A) : 205 ° C), acryloyl compound (Compound described in JP-A 2002-80616: 300 ° C. or more) (the parenthesized data are Tg). In particular, when transparency is required, it is preferable to use an alicyclic polyolefin or the like.

  When the gas barrier film of the present invention is used in combination with a polarizing plate, it is preferable that the barrier laminate of the gas barrier film faces the inside of the cell and is arranged on the innermost side (adjacent to the element). At this time, since the gas barrier film is disposed inside the cell from the polarizing plate, the retardation value of the gas barrier film is important. The usage form of the gas barrier film in such an embodiment includes a gas barrier film using a base film having a retardation value of 10 nm or less and a circularly polarizing plate (1/4 wavelength plate + (1/2 wavelength plate) + linearly polarizing plate. ) Or a linear barrier plate combined with a gas barrier film using a base film having a retardation value of 100 nm to 180 nm, which can be used as a quarter wavelength plate.

As a base film having a retardation of 10 nm or less, cellulose triacetate (Fuji Film Co., Ltd .: Fuji Tac), polycarbonate (Teijin Chemicals Co., Ltd .: Pure Ace, Kaneka: Elmec Co., Ltd.), cycloolefin polymer (JSR Co., Ltd.) ): Arton, Nippon Zeon Co., Ltd .: Zeonoa), cycloolefin copolymer (Mitsui Chemicals Co., Ltd .: Appel (pellet), Polyplastic Co., Ltd .: Topas (pellet)) Polyarylate (Unitika Co., Ltd.): U100 (pellet) )), Transparent polyimide (Mitsubishi Gas Chemical Co., Ltd .: Neoprim) and the like.
Moreover, as a quarter wavelength plate, the film adjusted to the desired retardation value by extending | stretching said film suitably can be used.

Since the gas barrier film in the present invention is used for an organic EL device, the plastic film is transparent, that is, the light transmittance is usually 80% or more, preferably 85% or more, more preferably 90% or more. The light transmittance is calculated by measuring the total light transmittance and the amount of scattered light using the method described in JIS-K7105, that is, an integrating sphere light transmittance measuring device, and subtracting the diffuse transmittance from the total light transmittance. be able to.
Even when the gas barrier film of the present invention is used for display, transparency is not necessarily required when it is not installed on the observation side. Therefore, in such a case, an opaque material can be used as the plastic film. Examples of the opaque material include polyimide, polyacrylonitrile, and known liquid crystal polymers.
Although there is no restriction | limiting in particular in the thickness of the plastic film used for the gas barrier film of this invention, Typically, it is 1-800 micrometers, Preferably it is 10-200 micrometers. These plastic films may have functional layers such as a transparent conductive layer and a primer layer. The functional layer is described in detail in paragraph numbers 0036 to 0038 of JP-A-2006-289627. Examples of functional layers other than these include matting agent layers, protective layers, antistatic layers, smoothing layers, adhesion improving layers, light shielding layers, antireflection layers, hard coat layers, stress relaxation layers, antifogging layers, and antifouling layers. , Printing layer, easy adhesion layer and the like.

(Inorganic layer)
The inorganic layer is not particularly limited as long as it is composed of an inorganic material and has a gas barrier property. Typically, the inorganic substance includes boron, magnesium, aluminum, silicon, titanium, zinc, tin oxide, nitride, oxynitride, carbide, hydride, and the like. These may be pure substances or mixtures. Of these, aluminum oxide, nitride or oxynitride, or silicon oxide, nitride or oxynitride is preferable. Although it does not specifically limit regarding the thickness of each inorganic layer which comprises a gas barrier layer, Typically, it is preferable to exist in the range of 5 nm-500 nm per layer, More preferably, it is 10 nm-200 nm per layer.

As a method for forming the inorganic layer, any method can be used as long as the target thin film can be formed. For example, a sol-gel method, a sputtering method, a vacuum deposition method, an ion plating method, a plasma CVD method, and the like are suitable, and specifically, Japanese Patent Registration No. 3400324, Japanese Patent Application Laid-Open No. 2002-322561, Japanese Patent Application Laid-Open No. 2002-361774. Can be employed.
In particular, when a silicon compound is formed, it is preferable to employ any one of inductively coupled plasma CVD, PVD or CVD using a microwave and a magnetic field-applied plasma set to electron cyclotron resonance conditions, Most preferably, a formation method by inductively coupled plasma CVD is employed. CVD (ECR-CVD) using microwaves set to inductively coupled plasma CVD or electron cyclotron resonance conditions and plasma applied with a magnetic field is described in, for example, Chemical Society of Japan, CVD Handbook, p. 284 (1991). It can be implemented by the method. PVD (ECR-PVD) using microwaves set to electron cyclotron resonance conditions and plasma applied with a magnetic field is, for example, Ono et al., Jpn. J. Appl. Phys. 23, No. 8, L534 ( 1984). As a raw material when using the CVD, a gas source such as silane or a liquid source such as hexamethyldisilazane can be used as a silicon supply source.

(Organic layer)
The gas barrier layer in the present invention preferably has an organic layer. In order to improve the brittleness and barrier property of the inorganic layer made of the above-mentioned inorganic substance, one or more organic layers are provided adjacent to the organic layer.

  The organic layer can be formed using (1) a method using an inorganic oxide layer prepared by using a sol-gel method, (2) a method of laminating an organic substance by coating or vapor deposition, or the like. Moreover, when laminating | stacking an organic substance by application | coating, a solid film can also be obtained by melt | dissolving a solid organic substance with a normal temperature and normal thickness with a solvent, and apply | coating and drying. In this case, a method in which curing is not performed can be used. (1) and (2) may be used in combination. For example, after forming a thin film on the resin film by the method (1), an inorganic oxide layer is formed, and then the method (2) is used. A thin film may be formed. Hereinafter, these methods will be described in order.

(1) Sol-gel method The sol-gel method is a method in which a metal alkoxide is preferably hydrolyzed and polycondensed in a solution or in a coating film to obtain a dense thin film. At this time, an organic-inorganic hybrid material may be used in combination with a resin.

  Examples of the metal alkoxide used in the sol-gel method include alkoxysilane and / or metal alkoxide other than alkoxysilane. As the metal alkoxide other than alkoxysilane, zirconium alkoxide, titanium alkoxide, aluminum alkoxide and the like are preferable.

  The polymer used in combination during the sol-gel reaction preferably has a hydrogen bond forming group. Examples of resins having hydrogen bond-forming groups include hydroxyl group-containing polymers and derivatives thereof (polyvinyl alcohol, polyvinyl acetal, ethylene-vinyl alcohol copolymers, phenol resins, methylol melamine, and derivatives thereof); carboxyl groups Polymers and derivatives thereof (mono or copolymers containing units of polymerizable unsaturated acids such as poly (meth) acrylic acid, maleic anhydride, itaconic acid, and esterified products of these polymers (vinyl esters such as vinyl acetate, Homo- or copolymers containing units such as (meth) acrylic acid esters such as methyl methacrylate)); polymers having an ether bond (polyalkylene oxide, polyoxyalkylene glycol, polyvinyl ether, silicon resin, etc.); amide bond Having a polymer (> N COR) -bond (wherein R represents a hydrogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent) N- of polyoxazoline or polyalkyleneimine Acylated product);> polyvinylpyrrolidone having a NC (O) -bond and derivatives thereof; polyurethane having a urethane bond; polymer having a urea bond, and the like.

  Alternatively, an organic-inorganic hybrid material can be prepared by using a monomer in combination during the sol-gel reaction and polymerizing the monomer during or after the sol-gel reaction.

During the sol-gel reaction, the metal alkoxide is hydrolyzed and polycondensed in water and an organic solvent. At this time, it is preferable to use a catalyst. As the hydrolysis catalyst, an acid (organic or inorganic acid) is generally used.
The amount of the acid used is 0.0001 to 0.05 mol per 1 mol of metal alkoxide (alkoxysilane and other metal alkoxide in the case of containing alkoxysilane and other metal alkoxide), and preferably is 0.00. 001-0.01 mol. After hydrolysis, a basic compound such as an inorganic base or an amine may be added to bring the pH of the solution to near neutrality to promote condensation polymerization.

In addition, other sol-gel catalysts such as metal chelate compounds having Al, Ti, and Zr as the central metal, organometallic compounds such as tin compounds, and metal salts such as alkali metal salts of organic acids can be used in combination.
The proportion of the sol-gel catalyst in the composition is preferably 0.01 to 50% by mass, more preferably 0.1 to 50% by mass, and still more preferably 0.5 to 10%, based on the alkoxysilane that is the raw material of the sol liquid. % By mass.

  Next, the solvent used for the sol-gel reaction will be described. The solvent uniformly mixes each component in the sol liquid, adjusts the solid content of the composition, and at the same time allows it to be applied to various coating methods to improve the dispersion stability and storage stability of the composition. . These solvents are not particularly limited as long as they can fulfill the above purpose. Preferable examples of these solvents include water and organic solvents that are highly miscible with water.

For the purpose of adjusting the speed of the sol-gel reaction, an organic compound capable of multidentate coordination may be added to stabilize the metal alkoxide. Examples of organic compounds capable of multidentate coordination include β-diketones and / or β-ketoesters, and alkanolamines.
Specific examples of the β-diketones and / or β-ketoesters include acetylacetone, methyl acetoacetate, ethyl acetoacetate, acetoacetate-n-propyl, acetoacetate-i-propyl, acetoacetate-n-butyl, acetoacetate. Acetic acid-sec-butyl, acetoacetic acid-tert-butyl, 2,4-hexane-dione, 2,4-heptane-dione, 3,5-heptane-dione, 2,4-octane-dione, 2,4-nonane -Dione, 5-methyl-hexane-dione and the like can be mentioned. Of these, ethyl acetoacetate and acetylacetone are preferred, and acetylacetone is particularly preferred. These β-diketones and / or β-ketoesters may be used alone or in combination of two or more.
These compounds capable of multidentate coordination can also be used for the purpose of adjusting the reaction rate when the metal chelate compound is used as a sol-gel catalyst.

  Next, a method for coating the sol-gel reaction composition will be described. The sol solution can form a thin film on the transparent film by a coating method such as curtain flow coating, dip coating, spin coating or roll coating. In this case, the hydrolysis may be performed at any time during the production process. For example, a solution of a required composition is hydrolyzed and partially condensed to prepare a desired sol solution, which is applied and dried, and a solution of the required composition is prepared and dried while hydrolyzing and partially condensing simultaneously. Method, application-After primary drying, a method of applying a water-containing liquid necessary for hydrolysis repeatedly and applying hydrolysis can be suitably employed. In addition, the coating method can take various forms. However, when productivity is important, each of the lower layer coating solution and the upper layer coating solution is required on a slide Geyser having a multistage discharge port. A method (simultaneous multi-layer method) is preferably used in which the discharge flow rate is adjusted so that the coating amount is obtained, and the formed multilayer flow is continuously placed on a support and dried.

  The drying temperature after coating is preferably 150 to 350 ° C, more preferably 150 to 250 ° C, and still more preferably 150 to 200 ° C.

In order to make the film after coating and drying more dense, irradiation with energy rays may be performed. Although there is no restriction | limiting in particular in the kind of irradiation radiation, In consideration of the influence with respect to a deformation | transformation and modification | denaturation of a support body, irradiation of an ultraviolet-ray, an electron beam, or a microwave can be used especially preferable. The irradiation intensity is ^{30mJ / cm 2 ~500mJ / cm 2} , particularly preferably ^{50mJ / cm 2 ~400mJ / cm 2} . The irradiation temperature can be employed without limitation between room temperature and the deformation temperature of the support, and is preferably 30 ° C to 150 ° C, particularly preferably 50 ° C to 130 ° C.

(2) Method of laminating organic materials by coating or vapor deposition (organic layer)
The organic layer in the present invention contains an organic polymer as a main component. Examples of the organic polymer include polyurea, polyurethane, polyamide, polyimide, polyacrylate, and polymethacrylate. The organic polymer may be an addition polymerization polymer or a condensation polymerization polymer. The addition polymerization polymer may be a homopolymer or a copolymer. The organic polymer may be cross-linked. The organic polymer contained in the organic layer may be one type or a mixture of two or more types. The organic polymer of the present invention is formed by coating the polymer or polymerizing and / or crosslinking the monomer and / or oligomer when forming the organic layer.

  In the present invention, the organic layer is substantially free from a liquid organic compound. The liquid organic compound means an organic compound having a melting point of less than 25 ° C. and a boiling point of 25 ° C. or more. The phrase “the organic layer does not substantially contain a liquid organic compound” means that the content of the liquid organic compound contained in the organic layer is less than 0.5% by mass of the organic layer. In this invention, it is preferable that the content rate of the liquid organic compound contained in an organic layer is less than 0.1 mass% of an organic layer, and it is still more preferable that it is less than 0.01 mass%. That is, in the present invention, 99.5% by mass or more of the organic compound contained in the organic layer is solid at 25 ° C., and 99.9% by mass or more of the organic compound contained in the organic layer is solid at 25 ° C. It is particularly preferable that 99.99% by mass or more of the organic compound contained in the organic layer is solid at 25 ° C.

According to the study by the present inventors, it has been found that an organic polymer or a solid organic compound does not adversely affect the organic EL element, but a liquid organic compound adversely affects the organic EL element. Although not bound by any theory, it is assumed that this is because when an organic EL element is produced on the gas barrier layer, a liquid organic compound diffuses from the organic layer of the gas barrier layer to the organic EL element part. Is done. The liquid organic compound contained in the organic layer is mainly an unreacted liquid monomer used when the organic layer is installed. For this reason, in this invention, when installing an organic layer, a solid monomer is used and a liquid monomer is not used substantially. In addition, the higher the melting point of the same solid monomer, the smaller the adverse effect on the organic EL element. The melting point of the solid monomer is preferably 40 ° C to 400 ° C, more preferably 60 ° C to 300 ° C.
Note that a volatile organic solvent may be used when the organic layer is installed, but the volatile organic solvent remaining in the organic layer is contrary to the spirit of the present invention. In the present invention, the organic solvent used for installing the organic layer has a boiling point of 200 ° C. or lower, preferably 150 ° C. or lower, more preferably 100 ° C. or lower. These organic solvents are used so that the organic solvent does not substantially remain.

  In the present invention, high adhesion between the inorganic layer and the organic layer is important for maintaining the film strength. For this purpose, it is preferable to use a solid monomer having a carboxyl group or a phosphonic acid group as the solid monomer. The carboxyl group or phosphonic acid group is particularly effective when the inorganic layer is an oxide, nitride or oxynitride of a metal selected from Si, Al, In, Sn, Zn and Ti. The ratio of the carboxyl group- or phosphonic acid group-containing solid monomer to the total solid monomer used for installing the organic layer is preferably 0.1% by mass to 50% by mass, more preferably 0.5% by mass to 30% by mass, and 2% by mass. -20% by weight is particularly preferred.

Examples of the method for forming the organic layer include a vacuum film forming method. Although there is no restriction | limiting in particular as a vacuum film-forming method, Film-forming methods, such as vapor deposition and plasma CVD, are preferable, and the resistance heating vapor deposition method which is easy to control a film-forming rate is more preferable. In the present invention, an organic polymer layer is formed by polymerizing an organic compound during film formation or after film formation. The method for polymerizing the organic compound is not particularly limited, but heat polymerization, light (ultraviolet ray, visible light) polymerization, electron beam polymerization, plasma polymerization, or a combination thereof is preferably used. When performing heat polymerization, the plastic film used as a base material needs to have appropriate heat resistance. In this case, at least the Tg (glass transition temperature) of the plastic film needs to be higher than the heating temperature. When performing photopolymerization, it is necessary to include a photopolymerization initiator in the organic layer. In the present invention, a photopolymerization initiator that is solid at room temperature is selected. The photoinitiator is deposited simultaneously with the solid monomer.
Post-polymerization may be performed to convert unreacted monomers into a polymer. Post polymerization is performed using heating, light (ultraviolet ray, visible light) irradiation, electron beam irradiation, plasma irradiation, and a combination thereof. The post polymerization may be performed immediately after the organic layer is installed or may be performed after all the layers are installed. When a plurality of organic layers are installed, post polymerization may be performed for each organic layer installation.
The film thickness of the organic layer is not particularly limited, but if it is too thin, it will be difficult to obtain film thickness uniformity, and if it is too thick, cracks will be generated by external force and the barrier properties will be reduced. From this viewpoint, the thickness of the adjacent organic layer is preferably 10 nm to 2000 nm, more preferably 20 nm to 1000 nm, and most preferably 50 nm to 500 nm.

The monomer used in the method for forming the organic layer mainly composed of a polymer obtained by crosslinking the monomer is not particularly limited as long as it contains a group that can be crosslinked by ultraviolet rays or electron beams, but an acryloyl group or It is preferable to use a monomer having a methacryloyl group or an oxetane group. For example, epoxy (meth) acrylate, urethane (meth) acrylate, isocyanuric acid (meth) acrylate, pentaerythritol (meth) acrylate, trimethylolpropane (meth) acrylate, ethylene glycol (meth) acrylate, polyester (meth) acrylate, etc. Among these, it is preferable that a polymer obtained by crosslinking a monomer having a bifunctional or higher functional acryloyl group or methacryloyl group as a main component. These monomers having a bifunctional or higher functional acryloyl group or methacryloyl group may be used as a mixture of two or more kinds, or as a mixture of monofunctional (meth) acrylates.
Moreover, as a monomer which has oxetane group, it is preferable to use the monomer which has a structure described in Unexamined-Japanese-Patent No. 2002-356607 General formula (3)-(6). In this case, you may mix these arbitrarily.

In the present invention, the organic layer is preferably composed of a radical polymerizable compound and / or a polymer of a cationic polymerizable compound having an ether group as a functional group.
(Polymerizable compound)
The polymerizable compound used in the present invention is a compound having an ethylenically unsaturated bond at the terminal or side chain and / or a compound having epoxy or oxetane at the terminal or side chain. Of these, compounds having an ethylenically unsaturated bond at the terminal or side chain are preferred. Examples of compounds having an ethylenically unsaturated bond at the terminal or side chain include (meth) acrylate compounds (acrylates and methacrylates are collectively referred to as (meth) acrylates), acrylamide compounds, styrene compounds, and anhydrous maleic compounds. An acid etc. are mentioned.

As the (meth) acrylate compound, (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate and the like are preferable.
As the styrene compound, styrene, α-methylstyrene, 4-methylstyrene, divinylbenzene, 4-hydroxystyrene, 4-carboxystyrene and the like are preferable.

Although the specific example of a (meth) acrylate type compound is shown below, this invention is not limited to these.

 Furthermore, in addition to the above, the gas barrier layer used in the present invention is provided with a desired functional layer between the base film, the organic layer, the inorganic layer, or between the gas barrier layer and the adhesive layer, on the outermost side of the film. be able to. Examples of such a functional layer include a smoothing layer / adhesion improving layer, an antireflection layer, and an antistatic layer.

Water vapor permeability at 40 ° C. · 90% relative humidity of the gas barrier layer used in the present invention is preferably not more than 0.01g / m ² · day, more preferably at most 0.001g / m ² · day 0.0001 g / m ² · day or less is particularly preferable.
In addition, the thickness of the gas barrier layer used in the present invention is preferably 10 to 200 μm, and more preferably 25 to 100 μm.

(Organic EL device)
Next, an organic EL element (hereinafter referred to as “organic EL element of the present invention”) will be described.

The organic EL device of the present invention has a pair of electrodes (a cathode and an anode) on a non-translucent substrate, and includes an organic light emitting layer (hereinafter simply referred to as “light emitting layer”) between both electrodes. It has a compound layer. In view of the properties of the light emitting element, at least one of the anode and the cathode is preferably transparent.
As an aspect of lamination of the organic compound layer in the present invention, an aspect in which a hole transport layer, a light emitting layer, and an electron transport layer are laminated in this order from the anode side is preferable. Furthermore, a charge blocking layer or the like may be provided between the hole transport layer and the light-emitting layer, or between the light-emitting layer and the electron transport layer. A hole injection layer may be provided between the anode and the hole transport layer, and an electron injection layer may be provided between the cathode and the electron transport layer. Each layer may be divided into a plurality of secondary layers.

(Non-translucent substrate)
As the non-transparent substrate in the present invention, a known substrate used for a top emission type organic EL element can be adopted. That is, resin films exemplified as barrier film equipment, metal foils such as aluminum, nickel, and stainless steel, glass substrates and the like can be used, but a light-impermeable functional layer such as a reflective layer or an irregular reflection preventing layer is provided. The substrate is shown. Among them, a substrate in which a thin metal layer is deposited on a resin film by vapor deposition, sputtering, or the like, and a film in which irregular reflection is prevented by blackening the metal surface are preferably used.

(anode)
The anode usually has a function as an electrode for supplying holes to the organic compound layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element. , Can be appropriately selected from known electrode materials. As described above, the anode is usually provided as a transparent anode.

  Suitable examples of the material for the anode include metals, alloys, metal oxides, conductive compounds, and mixtures thereof. Specific examples of the anode material include conductive metals such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), etc. Metals such as oxides, gold, silver, chromium, nickel, and mixtures or laminates of these metals and conductive metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, polyaniline, polythiophene, polypyrrole, etc. Organic conductive materials, and laminates of these with ITO. Among these, conductive metal oxides are preferable, and ITO is particularly preferable from the viewpoints of productivity, high conductivity, transparency, and the like.

  The anode is composed of, for example, a wet method such as a printing method or a coating method, a physical method such as a vacuum deposition method, a sputtering method or an ion plating method, or a chemical method such as a CVD or plasma CVD method. It can be formed on the non-translucent substrate according to a method appropriately selected in consideration of suitability for the material to be used. For example, when ITO is selected as the anode material, the anode can be formed according to a direct current or high frequency sputtering method, a vacuum deposition method, an ion plating method, or the like.

  In the organic EL device of the present invention, the formation position of the anode is not particularly limited and can be appropriately selected according to the use and purpose of the light emitting device. It is preferably formed on the non-translucent substrate. In this case, the anode may be formed on the entire one surface of the non-translucent substrate, or may be formed on a part thereof. The patterning for forming the anode may be performed by chemical etching such as photolithography, or may be performed by physical etching such as laser, or vacuum deposition or sputtering with a mask overlapped. It may be performed by a lift-off method or a printing method. The thickness of the anode can be appropriately selected depending on the material constituting the anode and cannot be generally defined, but is usually about 10 nm to 50 μm, and preferably 50 nm to 20 μm.

The resistance value of the anode is preferably 10 ³ Ω / □ or less, and more preferably 10 ² Ω / □ or less. When the anode is transparent, it may be colorless and transparent or colored and transparent. In order to take out light emission from the transparent anode side, the transmittance is preferably 60% or more, and more preferably 70% or more. The transparent anode is described in detail in the book “New Development of Transparent Electrode Films” published by CMC (1999), supervised by Yutaka Sawada, and the matters described here can be applied to the present invention. In the case of using a plastic substrate having low heat resistance, a transparent anode formed using ITO or IZO at a low temperature of 150 ° C. or lower is preferable.

(cathode)
The cathode usually has a function as an electrode for injecting electrons into the organic compound layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element, It can select suitably from well-known electrode materials. Examples of the material constituting the cathode include metals, alloys, metal oxides, electrically conductive compounds, and mixtures thereof. Specific examples include Group 1 metals (for example, Li, Na, K, Cs, etc.), Group 2 metals (for example, Mg, Ca, etc.), gold, silver, lead, aluminum, sodium-potassium alloy, lithium-aluminum alloy, magnesium. -Rare earth metals such as silver alloys, indium, ytterbium, and the like. These may be used alone, but two or more can be suitably used in combination from the viewpoint of achieving both stability and electron injection.

  Among these, the material constituting the cathode is preferably a Group 1 metal or a Group 2 metal from the viewpoint of electron injection, and a material mainly composed of aluminum is preferable from the viewpoint of excellent storage stability. The material mainly composed of aluminum is aluminum alone, an alloy of aluminum and 0.01 to 10% by mass of Group 1 metal or Group 2 metal, or a mixture thereof (for example, lithium-aluminum alloy, magnesium-aluminum alloy). Say. The materials for the cathode are described in detail in JP-A-2-15595 and JP-A-5-121172, and the materials described in these public relations can also be applied in the present invention.

  There is no restriction | limiting in particular about the formation method of a cathode, According to a well-known method, it can carry out. For example, the cathode described above is configured from a wet method such as a printing method or a coating method, a physical method such as a vacuum deposition method, a sputtering method, or an ion plating method, or a chemical method such as CVD or plasma CVD method. It can be formed according to a method appropriately selected in consideration of suitability with the material. For example, when a metal or the like is selected as the cathode material, one or more of them can be simultaneously or sequentially performed according to a sputtering method or the like. Patterning when forming the cathode may be performed by chemical etching such as photolithography, physical etching by laser, or the like, or by vacuum deposition or sputtering with the mask overlaid. It may be performed by a lift-off method or a printing method.

In the present invention, the cathode formation position is not particularly limited, and may be formed on the entire organic compound layer or a part thereof. Moreover, you may insert the dielectric material layer by the thickness of 0.1-5 nm between a cathode and the said organic compound layer with the fluoride, oxide, etc. of 1 group metal or 2 group metals. This dielectric layer can also be regarded as a kind of electron injection layer. The dielectric layer can be formed by, for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like. The thickness of the cathode can be appropriately selected depending on the material constituting the cathode and cannot be generally defined, but is usually about 10 nm to 5 μm, and preferably 50 nm to 1 μm.
Further, the cathode may be transparent or opaque. The transparent cathode can be formed by depositing a thin cathode material to a thickness of 1 to 10 nm and further laminating a transparent conductive material such as ITO or IZO.

(Organic compound layer)
The organic EL device of the present invention has at least one organic compound layer including a light emitting layer, and as the organic compound layer other than the light emitting layer, as described above, a hole transport layer, an electron transport layer, a charge Examples of the layer include a block layer, a hole injection layer, and an electron injection layer.

(Formation of organic compound layer)
In the organic EL device of the present invention, each layer constituting the organic compound layer can be suitably formed by any of a dry film forming method such as a vapor deposition method and a sputtering method, a transfer method, and a printing method.

(Light emitting layer)
The light-emitting layer receives holes from the anode, the hole injection layer, or the hole transport layer when an electric field is applied, receives electrons from the cathode, the electron injection layer, or the electron transport layer, and recombines holes and electrons. It is a layer which has the function to provide and to emit light. The light emitting layer in the present invention may be composed of only a light emitting material, or may be a mixed layer of a host material and a light emitting material. The light emitting material may be a fluorescent light emitting material or a phosphorescent light emitting material, and the dopant may be one type or two or more types. The host material is preferably a charge transport material. The host material may be one type or two or more types, and examples thereof include a configuration in which an electron transporting host material and a hole transporting host material are mixed. Further, the light emitting layer may include a material that does not have charge transporting properties and does not emit light. Further, the light emitting layer may be a single layer or two or more layers, and each layer may emit light in different emission colors.

  Examples of fluorescent materials that can be used in the present invention include, for example, benzoxazole derivatives, benzimidazole derivatives, benzothiazole derivatives, styrylbenzene derivatives, polyphenyl derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, naphthalimide derivatives, coumarin derivatives. , Condensed aromatic compounds, perinone derivatives, oxadiazole derivatives, oxazine derivatives, aldazine derivatives, pyralidine derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives, quinacridone derivatives, pyrrolopyridine derivatives, thiadiazolopyridine derivatives, cyclopentadiene derivatives, styryl Of amine derivatives, diketopyrrolopyrrole derivatives, aromatic dimethylidin compounds, metal complexes of 8-quinolinol derivatives and pyromethene derivatives And various metal complexes typified by metal complex, polythiophene, polyphenylene, polyphenylene vinylene polymer compounds include compounds such as organic silane derivatives.

  Examples of the phosphorescent material that can be used in the present invention include a complex containing a transition metal atom or a lanthanoid atom. Although it does not specifically limit as a transition metal atom, Preferably, ruthenium, rhodium, palladium, tungsten, rhenium, osmium, iridium, and platinum are mentioned, More preferably, they are rhenium, iridium, and platinum. Examples of lanthanoid atoms include lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. Among these lanthanoid atoms, neodymium, europium, and gadolinium are preferable.

  Examples of the ligand of the complex include G. Wilkinson et al., Comprehensive Coordination Chemistry, Pergamon Press, 1987, H. Yersin, “Photochemistry and Photophysics of Coordination Compounds,” Springer-Verlag, 1987, Akio Yamamoto. Examples of the ligands described in the book “Organic Metal Chemistry-Fundamentals and Applications-” published in 1982 by Hankabosha. Specific ligands are preferably halogen ligands (preferably chlorine ligands), nitrogen-containing heterocyclic ligands (eg, phenylpyridine, benzoquinoline, quinolinol, bipyridyl, phenanthroline, etc.), diketones Ligand (for example, acetylacetone), carboxylic acid ligand (for example, acetic acid ligand), carbon monoxide ligand, isonitrile ligand, cyano ligand, more preferably nitrogen-containing Heterocyclic ligand. The complex may have one transition metal atom in the compound, or may be a so-called binuclear complex having two or more. Different metal atoms may be contained at the same time.

  The phosphorescent material is preferably contained in the light emitting layer in an amount of 0.1 to 40% by mass, and more preferably 0.5 to 20% by mass. Examples of the host material contained in the light emitting layer in the present invention include those having a carbazole skeleton, those having a diarylamine skeleton, those having a pyridine skeleton, those having a pyrazine skeleton, those having a triazine skeleton, and aryl. Examples thereof include materials having a silane skeleton and materials exemplified in the sections of a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer described later. Although the thickness of a light emitting layer is not specifically limited, Usually, it is preferable that they are 1 nm-500 nm, it is more preferable that they are 5 nm-200 nm, and it is further more preferable that they are 10 nm-100 nm.

(Hole injection layer, hole transport layer)
The hole injection layer and the hole transport layer are layers having a function of receiving holes from the anode or the anode side and transporting them to the cathode side. Specifically, the hole injection layer and the hole transport layer are carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamines. Derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidin compounds, porphyrin compounds, organosilane derivatives, carbon , Etc. are preferable. The thicknesses of the hole injection layer and the hole transport layer are each preferably 500 nm or less from the viewpoint of lowering the driving voltage.

  The thickness of the hole transport layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm. In addition, the thickness of the hole injection layer is preferably 0.1 nm to 200 nm, more preferably 0.5 nm to 100 nm, and further preferably 1 nm to 100 nm. The hole injection layer and the hole transport layer may have a single-layer structure composed of one or more of the above-described materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions. .

(Electron injection layer, electron transport layer)
The electron injection layer and the electron transport layer are layers having a function of receiving electrons from the cathode or the cathode side and transporting them to the anode side. Specifically, the electron injection layer and the electron transport layer are triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, Carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, aromatic tetracarboxylic anhydrides such as naphthalene and perylene, phthalocyanine derivatives, metal complexes of 8-quinolinol derivatives, metal phthalocyanines, benzoxazoles and benzothiazoles as ligands It is preferably a layer containing various metal complexes typified by metal complexes, organosilane derivatives, and the like.

  The thicknesses of the electron injection layer and the electron transport layer are each preferably 50 nm or less from the viewpoint of lowering the driving voltage. The thickness of the electron transport layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm. In addition, the thickness of the electron injection layer is preferably 0.1 nm to 200 nm, more preferably 0.2 nm to 100 nm, and further preferably 0.5 nm to 50 nm. The electron injection layer and the electron transport layer may have a single layer structure composed of one or more of the above-described materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.

(Hole blocking layer)
The hole blocking layer is a layer having a function of preventing holes transported from the anode side to the light emitting layer from passing through to the cathode side. In the present invention, a hole blocking layer can be provided as an organic compound layer adjacent to the light emitting layer on the cathode side. Examples of the organic compound constituting the hole blocking layer include aluminum complexes such as BAlq, triazole derivatives, phenanthroline derivatives such as BCP, and the like. The thickness of the hole blocking layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm. The hole blocking layer may have a single layer structure composed of one or more of the above-described materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.

  The organic EL device of the present invention obtains light emission by applying a direct current (which may include an alternating current component if necessary) voltage (usually 2 to 15 volts) or a direct current between the anode and the cathode. be able to. Regarding the driving method of the organic EL device of the present invention, each of JP-A-2-148687, JP-A-6-301355, JP-A-5-290080, JP-A-7-134558, JP-A-8-234658, and JP-A-8-2441047. The driving methods described in Japanese Patent Laid-Open No. 2784615, US Pat. Nos. 5,828,429 and 6,023,308 can be applied.

  The typical application example of the organic EL element of the present invention has been described in detail above. However, the technology of the present invention can be widely applied to uses other than the organic EL element. For example, the present invention can be applied to an image display device such as a liquid crystal display device or electronic paper.

  The features of the present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

Example 1 Production and Evaluation of Gas Barrier Film A gas barrier film (Sample Nos. 101 to 104) in which an inorganic layer and an organic layer were provided on a base film was produced according to the following procedure. Details of the structure of each gas barrier film are as shown in Table 1. Polyethylene naphthalate (PEN, thickness 100 μm, manufactured by Teijin DuPont Co., Ltd., Q65A) film was used as the base film.

[1] Formation of inorganic layer (X) An inorganic layer of aluminum oxide was formed using a reactive sputtering apparatus. Specific film forming conditions are shown below.
The vacuum chamber of the reactive sputtering apparatus was evacuated to an ultimate pressure 5 × 10 ^-4 Pa by an oil rotary pump and a turbo molecular pump. Next, argon was introduced as a plasma gas, and power of 2000 W was applied from a plasma power source. A high-purity oxygen gas was introduced into the chamber, the film formation pressure was adjusted to 0.3 Pa, and the film was formed for a certain period of time to form an aluminum oxide inorganic layer. The obtained aluminum oxide film had a thickness of 40 nm and a film density of 3.01 g / cm ³ .

[2] Formation of Organic Layer (Y, Z) The organic layer is divided into a film formation method (organic layer Y) by solvent coating under normal pressure and a film formation method (organic layer Z) by flash vapor deposition under reduced pressure. Done using the street. Specific film formation contents are shown below.
[2-1] Film formation by solvent application under normal pressure [2-1-1] Film formation of organic layer (Y) 9 g of tripropylene glycol diacrylate (TPGDA, manufactured by Daicel Cytec) as a photopolymerizable acrylate, and 0.1 g of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, Irgacure 907) was dissolved in 190 g of methyl ethyl ketone to obtain a coating solution. This coating solution is applied to a base film using a wire bar, and an irradiance is applied using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 W / cm under a nitrogen purge with an oxygen concentration of 0.1% or less. The organic layer Y was formed by irradiating ultraviolet rays at 350 mW / cm ² and an irradiation amount of 500 mJ / cm ² . The film thickness was about 500 nm.

[2-2] Film formation by flash evaporation under reduced pressure [2-2-1] Film formation of organic layer (Z) BRS-0101 commercially available from Vitex Systems was used as the vapor deposition solution. This vapor deposition solution was vapor-deposited on the base film by the flash vapor deposition method under the condition that the internal pressure of the vacuum chamber was 3 Pa. Subsequently, the organic layer Z was formed by irradiating with an ultraviolet ray having a dose of ² J / cm ^{2 under} the same vacuum condition. The film thickness was about 1200 nm. The organic layer Z was formed by using an organic / inorganic laminated film forming apparatus (Guardian 200, manufactured by Vitex Systems).

[3] Production of gas barrier film The gas barrier film was produced by sequentially forming the inorganic layer and the organic layer on the base film according to the constitution of each sample described in Table 1. The production method was performed in the following two ways.
[3-1] Method of repeating organic layer formation by solvent coating and inorganic layer formation under reduced pressure (Lamination A)
Organic layers and inorganic layers were alternately laminated on the base film. When stacking the inorganic layer on the organic layer is placed in a vacuum chamber after forming the organic layer by solution coating under reduced pressure, the inorganic layer was held constant time following the state vacuum of 10 ^-3 Pa Was deposited. When the organic layer was laminated on the inorganic layer, the organic layer was formed by solvent coating immediately after the inorganic layer was formed.
[3-2] Method for consistently forming an organic layer and an inorganic layer under reduced pressure (Lamination B)
The organic layer and the inorganic layer were laminated | stacked using the above-mentioned organic-inorganic laminated film-forming apparatus Guardian200. In this apparatus, both the organic layer and the inorganic layer are formed in a reduced pressure environment, and the organic and inorganic layer forming chambers are connected. Therefore, it is possible to continuously form the film in a reduced pressure environment. Therefore, it is not released to the atmosphere until the barrier layer is completed.

[4] Physical property evaluation of gas barrier film Various physical properties of the gas barrier film were evaluated using the following apparatus.
[Layer structure (film thickness)]
The ultra-thin section of the film sample was observed and measured with a scanning electron microscope “S-900 type” manufactured by Hitachi, Ltd.

[Water vapor transmission rate (g / m ² / day)]
Metal Ca was directly deposited on the gas barrier film, and the film and the glass substrate were sealed with a commercially available sealing material for organic EL so that the deposited Ca was inside, thereby preparing a measurement sample. Next, the measurement sample was kept under the above temperature and humidity conditions, and the water vapor transmission rate was determined from the change in optical density of the metal Ca on the gas barrier film (the metal gloss decreased due to hydroxylation or oxidation).

(Production of organic EL element)
<Production of substrate>
An aluminum foil having a thickness of 150 μm was used as the non-translucent base material, an insulating layer was provided under the following conditions, and a substrate was produced.
A non-light-transmitting base material was introduced into a vacuum chamber, and an SiO ₂ film having a thickness of 0.05 μm was formed as an insulating layer by RF magnetron sputtering (condition: base material temperature 50 ° C.).

<Lower electrode>
This non-light-transmitting substrate was introduced into a vacuum chamber, and using an ITO target (indium: tin = 95: 5 (molar ratio)) with a SnO ₂ content of 10% by mass, DC magnetron sputtering (conditions: An ITO thin film (thickness 0.2 μm) was formed as a transparent electrode on a non-translucent substrate at a substrate temperature of 150 ° C. and an oxygen pressure of 1 × 10 ⁻³ Pa). The surface resistance of the ITO thin film was 10Ω / □.
Next, after putting the non-translucent base material in which the transparent electrode was formed in the washing container and carrying out IPA washing | cleaning, this was subjected to UV-ozone treatment for 30 minutes.
<Organic compound layer>
On this transparent electrode, copper phthalocyanine was deposited as a hole injection layer by a vacuum deposition method at a rate of 1 nm / second to provide 0.01 μm.

 Next, a hole transport layer was provided thereon. As a hole transport material, N, N′-dinaphthyl-N, N′-diphenylbenzidine (NPD) was deposited by a vacuum deposition method to provide a 0.3 μm hole transport layer.

On top of this, a phosphorescent material, tris (2-phenylpyridyl) iridium complex (Ir (ppy) ₃ ), and 4,4′-N, N′-dicarbazolebiphenyl (CBP) as a host compound were deposited at a deposition ratio of 5 / 100 and co-evaporated by a vacuum deposition method to provide a 0.03 μm light emitting layer.
A block layer was provided thereon. As an electron transport material used for the block layer, aluminum (III) bis (2-methyl-8-quinolinato) 4-phenylphenolate (Balq ₂ ) is used, and is deposited by vacuum deposition at a rate of 1 nm / second. A .01 μm block layer was provided.
Further thereon, tris (8-hydroxyquinolinato) aluminum (Alq ₃ ) was used as an electron transport material, and a 0.04 μm electron transport layer was provided by vacuum deposition at a rate of 1 nm / second.

Furthermore, LiF was vapor-deposited as an electron injection layer at a rate of 1 nm / second to provide a 0.002 μm electron injection layer.

<Back electrode>
Further, a patterned mask (a mask having a light emitting area of 2 mm × 2 mm) was placed on the electron injection layer, and 0.015 μm of Ag was deposited to form a transparent back electrode.
Aluminum lead wires were respectively connected from the lower electrode and the back electrode to form a light emitting laminate.
On this back electrode, an adhesive layer consisting of 95% 1,1- (bisacryloyloxymethyl) ethyl isocyanate (Showa Denko, Karenz BEI) and Irgacure 1700, 5% as an adhesive layer is laminated to a thickness of 0.08 mm. Furthermore, the gas barrier film produced above was laminated. Further, on the other surface of the non-translucent substrate, 1,1- (bisacryloyloxymethyl) ethyl isocyanate (manufactured by Showa Denko, Karenz BEI) is laminated with a thickness of 0.08 mm as an anti-curl layer, An organic EL device was obtained. The ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) was 0.9.

(Example 2)
In Example 1, an organic EL device was prepared in the same manner except that 1,1- (bisacryloyloxymethyl) ethyl isocyanate (manufactured by Showa Denko, Karenz BEI) was laminated with a thickness of 0.05 mm as the anti-curl layer. Obtained. The ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) was 1.8.

(Example 3)
In Example 1, a 50 μm polyethylene terephthalate resin film warped in advance with a curvature radius of 2 (1 / m) was applied as the anti-curl layer, and then 1,1- (bisacryloyloxymethyl) ethyl isocyanate ( An organic EL device was obtained in the same manner except that Showa Denko Kalenzu BEI) was laminated to a thickness of 0.01 mm. The ratio of (x1) × (y1) × (z1) to (x2) × (y2) × (z2) was 0.5.

(Examples 4 and 5)
An organic EL device was obtained in the same manner as in Examples 1 and 3 except that the following changes were made.

(Comparative Example 1)
In the organic EL element of Example 1, an anti-curl layer was not formed, and the others were performed in the same manner to produce an organic EL element.

 The organic EL elements obtained in the above examples and comparative examples were placed on a flat surface, and the subsequent results were confirmed. As a result, all the organic EL elements obtained in the examples of the present application were (floating at the four corners within 0.5 mm), but in the organic EL element obtained in Comparative Example 1, the curing shrinkage of the adhesive layer Thus, it was confirmed that both ends of the non-translucent substrate were floated by 3 mm or more from the plane.

According to the present invention, it is possible to reduce warpage in a top emission type organic EL element. For this reason, further thinning of the organic EL element can be expected.
The technology of the present invention can also be employed in solar cells and electronic paper. Further, the technique of the present invention can also be employed in an image display element that uses a gas barrier film as a substrate.

The schematic of the top emission type organic EL element of this invention is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Non-translucent base material 2 Electrode 3 Organic compound layer 4 Adhesive layer or smooth layer 5 Gas barrier layer 6 Anti-curl layer

Claims (6)

 It has at least a pair of electrode layers and an organic compound layer provided between the electrode layers on one surface of the non-translucent substrate, and adheres to the electrode far from the non-translucent substrate. An organic EL device in which a gas barrier layer is laminated via a layer or a smoothing layer, wherein an anti-curl layer is provided on the other surface of the non-translucent base material, EL element.  The volume shrinkage ratio at the time of curing of the anti-curl layer is set such that the cube root of the volume shrinkage ratio at the time of curing the adhesive layer or the smoothing layer, the elastic modulus, and the layer thickness (unit: μm) are x1, y1, and z1, respectively. (X1) × (y1) × (z1) of (x2) × (y2) × where the cube root, elastic modulus, and layer thickness (unit: μm) are x2, y2, and z2 in this order. The top emission type organic EL device according to claim 1, wherein the ratio to (z2) is 0.1 to 10. The top emission type organic EL device according to claim 2, wherein a ratio of (x1) x (y1) x (z1) to (x2) x (y2) x (z2) is 0.3 to 3. The top emission type organic EL device according to any one of claims 1 to 3, wherein the adhesive layer is mainly composed of a polymerized polymerizable (meth) acrylate monomer. The top emission type organic EL device according to any one of claims 1 to 4, wherein a decrease in elastic modulus of the anticurl layer when it contains water is 30% or less. It is a manufacturing method of the organic EL element of any one of Claims 1-5, Comprising: After curling a non-light-transmissive base material in the anti-curl layer side beforehand and providing an anti-curl layer, an adhesive layer or The manufacturing method of an organic EL element which provides a gas barrier film through a smoothing layer.

Images