JP2008218143A - Organic electroluminescence element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence element using a composite material substrate with a transparent electrode excelling in dimensional stability, stability of a resistance value, and transparency. <P>SOLUTION: This organic electroluminescence element includes the composite material substrate with a transparent electrode, and a luminescent layer. The organic electroluminescence element is characterized in that the composite material substrate with a transparent electrode includes: a plastic film containing a cross-linked resin and a glass fiber; one or more gas barrier layers formed on both surfaces of the plastic film; and transparent electrode layers formed on the gas barrier layers and containing In-Zn-O as a main constituent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence element.

  Flat panel displays (FPD) such as liquid crystal display devices and organic electroluminescence (organic EL) display devices are widely used as thin and space-saving display devices. In addition, with the mobile use of information terminal devices, demand for FPDs is rapidly expanding using plastic films and sheets as base materials.

  However, in order to use a plastic substrate for an active matrix type liquid crystal display element, a color filter substrate, an organic EL display element, an organic EL backlight or the like instead of a conventional glass substrate, there are some problems that must be solved. There are difficult challenges.

  That is, the first is dimensional stability, the second is gas barrier property, the third is transparency, the fourth is heat resistance, and the fifth is low resistance and stability of resistance value of the transparent electrode. Furthermore, characteristics such as low warpage of the substrate during the process, chemical resistance, and etching properties of the transparent electrode are also important. In addition, even if the individual material properties to be laminated are excellent, there is a possibility that problems such as peeling and breakage may occur during the process, and matching of laminated materials is also a big issue.

  Examples of conventional plastic substrates for liquid crystals include epoxy resin-based liquid crystal substrates described in Patent Document 1 (Japanese Patent Laid-Open No. 6-337408) and Patent Document 2 (Japanese Patent Laid-Open No. 7-120740). 3 (Japanese Patent Laid-Open No. 10-77321) and Patent Document 4 (Japanese Patent Laid-Open No. 10-90667) describe a transparent liquid crystal substrate using a (meth) acrylate resin. However, these conventional glass substitute plastic materials have a remarkably large linear expansion coefficient as compared with a glass plate, and particularly, when used for an active matrix display substrate, problems such as warpage in the manufacturing process and disconnection of wiring occur. Also, when used in a color filter substrate having a photolithographic process in the process, a substrate having a low linear expansion coefficient and high heat resistance is required to form RGB colors at predetermined positions with high definition and no color shift. Required. Furthermore, methods for forming an organic EL on a plastic substrate are disclosed in Patent Document 5 (Japanese Patent Laid-Open No. 2002-175875), Patent Document 6 (Japanese Patent Laid-Open No. 2002-190384), and the like. However, one of the reasons why glass substrates are not easily replaced by plastic substrates is that the linear expansion coefficient differs greatly between glass and plastic. Also, even in the case of uniform light emission on the surface like an organic EL backlight, the gas barrier layer and electrode layer on the plastic are mostly metal oxides, and the linear expansion coefficient with the plastic as the substrate Deflection, deformation, breakage, and the like due to the difference occur in the manufacturing heating process. Therefore, a reduction in the linear expansion coefficient of the plastic substrate is indispensable for these applications.

  Recently, a transparent composite composition described in Patent Document 7 (International Publication No. WO03 / 064530) or a patent document that can be suitably used for a liquid crystal display substrate, an organic EL element substrate, a color filter substrate, and the like containing an active matrix. No. 8 (International Publication No. WO03 / 064535 pamphlet), such as a transparent composite composition, has been proposed a plastic substrate having excellent characteristics such as linear expansion coefficient, transparency, and heat resistance. However, these are not used alone for a liquid crystal substrate or an organic EL substrate, but can be used for these applications only after providing a barrier layer or a transparent electrode layer.

  Patent Document 9 (Japanese Patent Laid-Open No. 2006-113322) describes a barrier film with a transparent electrode to which a barrier property that can be applied to a liquid crystal display substrate, an organic EL element, or the like is provided. However, there is no description about the linear expansion coefficient of the transparent plastic film, and there is a resin layer in which gas such as water vapor easily diffuses directly under the outermost transparent electrode. There is a problem to be solved.

Transparent electrodes used in FPDs are required to have higher quality as their performance increases. The most commonly used transparent electrode is ITO (Indium Tin Oxide), which has excellent properties such as film formation by sputtering and etching processability by hydrochloric acid-nitric acid strong acid. However, with the high definition of liquid crystal displays, improvements in electrode etching processability and excellent conductivity and stability have been demanded of materials, and development of new transparent conductive films has been activated. In particular, since IZO (Indium Zinc Oxide) is generally an amorphous film, it has excellent properties such as excellent etching properties and low internal stress. As methods for forming these IZOs on a plastic film, there are Patent Document 10 (Japanese Patent Laid-Open No. 7-235219) and Patent Document 11 (Japanese Patent Laid-Open No. 2000-243160). Patent Document 10 is intended to form a transparent conductive film having a relatively low resistance while keeping the substrate temperature at room temperature by using an IZO film as a transparent conductive film. Patent Document 11 discloses a low resistance with little resistance change between the resistance value immediately after the formation of the conductive film and the heat treatment within the range not exceeding the glass transition temperature of the polymer substrate in order to improve the productivity of the transparent conductive film. A transparent conductive film is to be formed.
JP-A-6-337408 JP-A-7-120740 JP 10-77321 A JP-A-10-90667 JP 2002-175875 A JP 2002-190384 A International Publication No. WO03 / 064530 Pamphlet International Publication No. WO03 / 064535 Pamphlet JP 2006-113322 A JP 7-235219 A JP 2000-243160 A

  However, the composite material substrate with a transparent electrode that can be suitably used for a liquid crystal display substrate including an active matrix, an organic EL element substrate, and a color filter substrate is not limited to the design of individual materials of a plastic substrate, a barrier layer, and a transparent electrode. Therefore, it is necessary to design a material configuration suitable for the process of compounding them. In particular, a plastic substrate for application to an organic EL element is required to have a very high shielding property such as water molecules and oxygen molecules while providing flexibility. In the case of a conductive film typified by conventional ITO, it is difficult to eliminate the disadvantage that fine break points are scattered when it is formed on the characteristics of a plastic substrate and a barrier layer structure suitable for this, and it was applied to an organic EL element. In some cases, the growth of dark spots was remarkable, making it difficult to put it to practical use. In other words, complicated materials and process issues such as plastic substrate material, barrier layer configuration, conductive film material and formation method, and appropriate evaluation after forming an organic EL element must be considered together. It cannot be solved with known techniques.

  Accordingly, the present invention has been made in view of such circumstances, and instead of a conventional glass substrate, a plastic is used for an active matrix type liquid crystal display element, a color filter substrate, an organic EL display element, an organic EL backlight, or the like. The present invention provides an organic electroluminescence device using a composite substrate with a transparent electrode, which is excellent in dimensional stability, resistance value stability, and transparency for using a substrate.

  According to the present invention for solving the above-mentioned problems, an organic electroluminescence element comprising a composite material substrate with a transparent electrode and a light emitting layer, wherein the composite material substrate with a transparent electrode comprises a crosslinked resin and glass fiber. And at least one gas barrier layer provided on both surfaces of the plastic film, and a transparent electrode layer provided on the gas barrier layer and containing In—Zn—O as a main component. An organic electroluminescent device is provided.

  According to the present invention, by using a composite substrate with a transparent electrode including a plastic film including a crosslinked resin and glass fiber and a transparent electrode including In-Zn-O as a main component, the expansion coefficient of the plastic film is increased. While being able to suppress low, the change of the resistance value before and behind a process can be suppressed. Moreover, by providing a gas barrier layer on both surfaces of the plastic film, the gas barrier property can be improved, and thereby dark spots on the substrate can be reduced. Therefore, it is possible to realize an organic electroluminescence device having excellent dimensional stability, resistance value stability and transparency in a well-balanced manner.

  In the organic electroluminescence device, the light emitting layer may include a light emitting layer host and a phosphorescent material.

  In the organic electroluminescence device, the glass fiber may be blended in an amount of 10 to 90% by weight based on the total weight of the plastic film.

  In the organic electroluminescence device, the linear expansion coefficient of the plastic film at 30 ° C. to 150 ° C. may be 0 ppm / ° C. or more and 40 ppm / ° C. or less.

In the organic electroluminescence element, the water vapor transmission rate of the composite material substrate with a transparent electrode may be 0.01 g / (m ² · 24 hr) or less (measured value at 40 ° C. and 90% RH based on JIS K7129B method).

When the sheet resistance value of the transparent electrode before the heat treatment at 180 ° C. is a and the sheet resistance value of the transparent electrode after the heat treatment at 180 ° C. is b in the composite substrate with a transparent electrode of the organic electroluminescence element. , B / a may be 0.8 or more and less than 1.5.
In the organic electroluminescence device, the gas barrier layer may contain silicon oxide, nitride, or nitride as a main component.
In the organic electroluminescence element, the composite substrate with a transparent electrode may further include an organic coat layer.

  ADVANTAGE OF THE INVENTION According to this invention, the organic electroluminescent element using the composite material board | substrate with a transparent electrode excellent in dimensional stability, stability of resistance value, and transparency is provided.

  A preferred embodiment of a composite substrate with a transparent electrode according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

The organic electroluminescence device of the present invention includes a composite material substrate with a transparent electrode and a light emitting layer. This composite material substrate with a transparent electrode is provided with a plastic film containing a crosslinked resin and glass fiber, a gas barrier layer provided on both surfaces of the plastic film, and provided on the gas barrier layer, with In—Zn—O as a main component. A transparent electrode layer.
FIG. 1 shows an example of an organic electroluminescence device according to an embodiment of the present invention. In FIG. 1, an organic electroluminescence element 10 includes a plastic film 1, gas barrier layers 2 and 4 provided on both surfaces of the plastic film 1, an organic coat layer 3 provided on the surface of the gas barrier layer 2, and a gas barrier layer 4. And a composite material substrate with a transparent electrode, including an IZO electrode 5 provided on the surface of the substrate. The organic EL element 10 is provided through an organic layer 6 provided on the surface of the IZO electrode 5 of the composite material substrate with a transparent electrode, a counter electrode 7 provided on the surface of the organic layer 6, and an adhesive 9. A stainless steel sealing can 8 is included.

  Hereinafter, each configuration will be described in detail.

(Plastic film)
The plastic film used in the present invention contains a crosslinked resin and glass fiber.
The plastic film is obtained by impregnating a glass fiber with a crosslinked resin and curing the crosslinked resin.
Examples of the crosslinked resin used for producing the plastic film of the present invention include (A) a resin obtained by crosslinking a reactive monomer such as acrylate with active energy rays and / or heat, or (B) an epoxy resin.

  In the present invention, the crosslinking is preferably performed after glass fibers described later are contained.

  A preferable cross-linked resin (A) is a transparent resin obtained by cross-linking of an acrylate (a1) having an alicyclic structure and at least one acrylate (a2) selected from a sulfur-containing acrylate and an acrylate having a fluorene skeleton. Resin. (A1) is a low refractive index monomer having a lower refractive index than glass fiber, and (a2) is a monomer having a higher refractive index than glass fiber. Both are described in detail below.

(A1) Low refractive index monomer As the reactive monomer having a refractive index lower than that of the glass fiber, various (meth) acrylates containing an alicyclic structure or an aliphatic chain can be used. A (meth) acrylate having an alicyclic structure is preferred from the surface.

  As the (meth) acrylate having an alicyclic structure, any (meth) acrylate having an alicyclic structure and having two or more functional groups may be used, and the following formula ( At least one (meth) acrylate selected from 1) and (2) is preferred.

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group. A represents 1 or 2, and b represents 0 or 1.)

(In the formula, X is a hydrogen atom, —CH ₃ , —CH ₂ OH, NH ₂ ,

を示し、Ｒ_３及びＲ_４は、Ｈまたは−ＣＨ_３、ｐは０または１である。）

R ₃ and R ₄ are H or —CH ₃ , and p is 0 or 1. )

In formula (1), dicyclopentadienyl diacrylate having a structure in which R ₁ and R ₂ are hydrogen, a is 1 and b is 0 is particularly preferred from the viewpoint of physical properties such as viscosity.

In the formula (2), in particular, perhydro-1,4,5,8- having a structure in which X is —CH ₂ OCOCH═CH ₂ , R ₃ and R ₄ are hydrogen, and p is 1. Dimethanonaphthalene-2,3,7- (oxymethyl) triacrylate, at least one acrylate selected from acrylates having a structure in which X, R ₃ and R ₄ are all hydrogen and p is 0 or 1 Is preferred. In particular, considering the viscosity and the like, norbornane dimethylol diacrylate having a structure in which X, R ₃ , and R ₄ are all hydrogen and p is 0 is most preferable. The (meth) acrylate of the formula (2) can be obtained by the method disclosed in JP-A-5-70523.

  As the reactive monomer having a refractive index lower than that of the glass fiber, the cyclic ether (meth) acrylate represented by the following formula (6) is also desirable because of its high transparency and heat resistance.

(In the formula, R ₁₈ and R ₁₉ each independently represent a hydrogen atom or a methyl group.)

(A2) High Refractive Index Monomer As the reactive monomer having a higher refractive index than glass fiber, various (meth) acrylates containing sulfur and aromatic rings can be used. A (meth) acrylate or a (meth) acrylate having a fluorene skeleton is preferred.

  The sulfur-containing (meth) acrylate used in the present invention may be a (meth) acrylate having two or more functional groups containing sulfur, and is represented by the following formula (3) from the viewpoint of heat resistance and transparency ( (Meth) acrylate is preferred.

(Wherein, X represents a sulfur or SO _2, Y is .n and m _.R 5 _{to R 10} showing the oxygen or sulfur each independently represent a hydrogen atom or a methyl group is 0-2.)

Among the (meth) acrylates represented by formula (3), X is sulfur, Y is oxygen, R _{5 to} R ₁₀ are all hydrogen, and n and m are both 1 because of reactivity, heat resistance and ease of handling. [4- (acryloyloxyethoxy) phenyl] sulfide is most preferred.

  The (meth) acrylate having a fluorene skeleton used in the present invention is not particularly limited as long as it is a (meth) acrylate having a fluorene skeleton and having two or more functional groups, but the following from the viewpoint of heat resistance and transparency. At least one (meth) acrylate selected from the formulas (4) and (5) is preferred.

(In the formula, R _{11 to} R ₁₄ each independently represents a hydrogen atom or a methyl group. R and s are 0 to 2.)

(In the formula, R _{15 to} R ₁₇ each independently represent a hydrogen atom or a methyl group.)

Among these, bis [4- (acryloyloxyethoxy) phenyl] fluorene in which R _{11 to} R ₁₄ are all hydrogen and r and s are 1 in the formula (4) is most preferable.

  These low-refractive index monomer and high-refractive index monomer can be mixed and crosslinked at an appropriate blending ratio according to the target refractive index, and the refractive index of the transparent resin is combined with the refractive index of the glass fiber. Can be adapted to

  In order to impart flexibility to the (meth) acrylate having two or more functional groups used in the present invention, a monofunctional (meth) acrylate may be used in combination as long as desired properties are not impaired. In this case, the blending amount is adjusted so that the refractive index of the entire resin component matches the refractive index of the glass fiber.

(Polymerization initiator)
In order to crosslink and cure the reactive monomer with active energy rays such as ultraviolet rays, it is preferable to add a photopolymerization initiator that generates radicals in the resin composition. Examples of such photopolymerization initiators include benzophenone, benzoin methyl ether, benzoin propyl ether, diethoxyacetophenone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,6-dimethylbenzoyl diphenylphosphine oxide, 2,4,6-trimethylbenzoyl. Examples thereof include diphenylphosphine oxide. Two or more of these photopolymerization initiators may be used in combination.

  The content of the photopolymerization initiator in the resin composition may be an appropriate amount to be cured, and a total of 100 (meth) acrylates (a-1) and (a-2) having two or more functional groups. The amount is preferably 0.01 to 2 parts by weight, more preferably 0.02 to 1 part by weight, and most preferably 0.1 to 0.5 part by weight with respect to parts by weight. When the amount of the photopolymerization initiator added is too large, the polymerization proceeds rapidly, and problems such as increased birefringence, coloring, and cracks during curing occur. On the other hand, if the amount is too small, the composition cannot be sufficiently cured, and there is a possibility that problems such as adhesion to the mold after crosslinking and removal cannot occur.

  When heat treatment is performed at a high temperature after curing by active energy rays and / or crosslinking by thermal polymerization, 250 to 300 ° C. in a nitrogen atmosphere or in a vacuum state for the purpose of reducing the linear expansion coefficient during the heat treatment step. It is preferable to add a heat treatment step for 1 to 24 hours.

  The epoxy resin (B) has a different refractive index after curing depending on the curing agent used. In the present invention, the refractive index after curing is lower than the refractive index of the glass fiber used. Or it will not be specifically limited if it becomes high.

  When glass fibers having a refractive index of 1.52 or more such as E glass or S glass are used as glass fibers, an epoxy resin having a low refractive index or an epoxy resin having a high refractive index can be prepared by using an acid anhydride as a curing agent. At least one selected from alicyclic epoxy resins having a low refractive index (e.g., the following formulas (7) to (12)) and triglycidyl isocyanurate having a moderate refractive index (the following formula (13)) A combination of an epoxy resin and (ii) a sulfur-containing epoxy resin having a relatively high refractive index (the following formula (14)) and at least one epoxy resin selected from a fluorene skeleton-containing epoxy resin (the following formula (15)) Is preferred.

  Among them, triglycidyl isocyanurate is more preferable as the component (i) from the viewpoint of heat resistance.

  On the other hand, when glass fibers having a refractive index of less than 1.52, such as NE glass, are used, (i) an alicyclic epoxy resin having a relatively low refractive index (the following formulas (7) to (12) )) And at least one epoxy resin selected from (ii) triglycidyl isocyanurate having a medium refractive index (the following formula (13)), and a sulfur-containing epoxy resin having a relatively high refractive index (below) A combination of at least one epoxy resin selected from the formula (14)) and a fluorene skeleton-containing epoxy resin (the following formula (15)) is preferable.

  Examples of the epoxy resin having a relatively low refractive index include alicyclic epoxy resins represented by the following formulas (7) to (12).

(In the formula, R ₆ represents an alkyl group or a trimethylolpropane residue, and q is 1 to 20.)

(Wherein R ₇ and R ₈ each independently represent a hydrogen atom or a methyl group, and r is 0 to 2).

  (In the formula, s is 0 to 2.)

  Further, triglycidyl isocyanurate having a medium refractive index is represented by the following formula (13).

  The sulfur-containing epoxy resin having a relatively high refractive index is not particularly limited as long as it contains sulfur and has two or more epoxy groups. From the viewpoint of heat resistance and transparency, the following formula (14 The epoxy resin shown in FIG.

(In the formula, X represents S or SO ₂ , Y represents O or S. R _{1 to} R ₄ each independently represents a hydrogen atom or a methyl group, and n is 0 to 2.)

Among the epoxy resins represented by formula (14), bisphenol S in which X is SO ₂ , Y is oxygen, R _{5 to} R ₁₀ are all hydrogen, and n is 0 to 1 because of reactivity, heat resistance, and ease of handling. Is most preferred.

  The fluorene skeleton-containing epoxy resin having a relatively high refractive index is not particularly limited as long as it contains an fluorene skeleton and has two or more epoxy groups, but the following formula is used from the viewpoint of heat resistance and transparency. The epoxy resin represented by (15) is preferred.

(In the formula, R ₅ represents hydrogen or a methyl group, and m is 0 to 2.)

  Epoxy resins having different refractive indexes after curing can be mixed and cured at an appropriate blending ratio according to the target refractive index, and the refractive index of the epoxy resin can be adjusted to the refractive index of the glass fiber.

  The epoxy resin used in the present invention may be used in combination with a monofunctional epoxy compound within a range that does not impair the desired characteristics for imparting flexibility. In this case, the blending amount is adjusted so that the refractive index of the entire resin matches the refractive index of the glass fiber.

  The epoxy resin used in the present invention is used after being cured by heating or irradiation with active energy rays in the presence of a curing agent or a polymerization initiator. The curing agent is not particularly limited, but an acid anhydride-based curing agent or a cationic catalyst is preferable because an excellent transparent cured product can be easily obtained.

  Examples of acid anhydride curing agents include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl nadic anhydride, nadic anhydride, glutaric anhydride, Examples include methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl hydrogenated nadic anhydride, hydrogenated nadic anhydride, etc. Among them, methyl hexahydrophthalic anhydride and methyl hydrogenated nadic anhydride are excellent because of their excellent transparency. Is preferred.

  When using an acid anhydride curing agent, it is preferable to use a curing accelerator in combination. Examples of the curing accelerator include 1,8-diaza-bicyclo (5,4,0) undecene-7, tertiary amines such as triethylenediamine, imidazoles such as 2-ethyl-4-methylimidazole, and triphenylphosphine. And phosphorus compounds such as tetraphenylphosphonium tetraphenylborate, quaternary ammonium salts, organometallic salts, and derivatives thereof, among which phosphorus compounds are preferred. These curing accelerators may be used alone or in combination of two or more.

  The amount of the acid anhydride curing agent used is preferably set to 0.5 to 1.5 equivalents of the acid anhydride group in the acid anhydride curing agent with respect to 1 equivalent of the epoxy group in the epoxy resin. 0.7-1.2 equivalent is more preferable.

  Cationic catalysts include acetic acid, benzoic acid, salicylic acid, p-toluenesulfonic acid and other organic acids, boron trifluoride amine complexes, boron trifluoride ammonium salts, aromatic diazonium salts, aromatic sulfonium salts, aromatic Examples thereof include cationic catalysts containing a group iodonium salt and an aluminum complex, and among these, a cationic catalyst containing an aluminum complex is preferred.

  Although the refractive index of the glass fiber mix | blended with the plastic film of this invention is not specifically limited, It is preferable to exist in the range of 1.50-1.57 so that adjustment of the refractive index of resin to combine is easy. . In particular, when the refractive index of the glass fiber is 1.50 to 1.54, a resin close to the Abbe number of the glass can be selected, which is preferable. When the Abbe numbers of the resin and glass are close, the refractive indexes of the two coincide in a wide wavelength region, and a high light transmittance is obtained in a wide wavelength region.

  The glass fibers used in the present invention may be any of glass fiber filaments (short fibers or long fibers), glass fiber woven fabrics, glass fiber nonwoven fabrics, etc., among which glass fiber woven fabrics are preferred. In the present invention, glass fiber does not include glass powder, glass beads, or 1 mm or less glass fiber (short fiber).

  Examples of the glass include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, quartz, low-inductivity glass, and high-inductivity glass. E glass, S glass, T glass, and NE glass, which have few impurities and are easily available, are preferred.

  When a glass fiber woven fabric is used as the glass fiber, the method of weaving the filament is not limited, and plain weave, Nanako weave, satin weave, twill weave, etc. can be applied, and plain weave is preferred.

  In general, the thickness of the glass fiber woven fabric is preferably 30 to 200 μm, and more preferably 40 to 150 μm.

  Only one glass fiber cloth such as a glass fiber woven cloth or a glass non-woven cloth may be used, or a plurality of glass fiber cloths may be used.

  As for the compounding quantity of the glass fiber in a plastic film composition, 10 to 90 weight% is preferable, More preferably, it is 20 to 80 weight%, More preferably, it is 30 to 70 weight%. When the blending amount of the glass fiber is less than this, the linear expansion coefficient tends to be large and the range does not fall within the scope of the present invention. On the other hand, when the blending amount is larger than this, the molded appearance tends to be lowered.

  The plastic film substrate thus obtained has a linear expansion coefficient at 30 ° C. to 150 ° C. of 0 ppm / ° C. or more and 40 ppm / ° C. or less, preferably 0 ppm / ° C. or more and 30 ppm / ° C. or less. is there. When the expansion coefficient is within the above range, warping of the plastic substrate during processing can be suppressed. In the present invention, the linear expansion coefficient is measured by the following method.

  According to JIS K7197, it measured using the TMA / SS120C type | mold thermal stress strain measuring apparatus by Seiko Electronics Co., Ltd.

(Gas barrier layer)
The composite substrate with a transparent electrode has at least one gas barrier layer on both sides of the plastic film.

  When the gas barrier layer is provided, the gas permeability of the plastic film is greatly reduced, so that the permeation of water vapor and oxygen contained in the outside air can be suppressed. For example, in an organic EL substrate, by suppressing gas permeation by the gas barrier layer, damage to the organic EL element can be reduced and the light emission life can be extended. In addition, expansion of the non-lighting area that increases with time during light emission can be suppressed.

  Even in the case of using it for a liquid crystal substrate, if there is no gas barrier layer, gas such as water vapor or oxygen is mixed into the element, which causes the display quality to deteriorate and shorten the life.

  In one embodiment of the present invention, at least one gas barrier layer is provided on each side of the plastic film. By having the gas barrier layer on both sides, not only gas permeation can be suppressed, but also dimensional change can be suppressed in the process of contacting the liquid such as cleaning during the process.

  As the gas barrier layer, it is preferable to provide an inorganic film having transparency. Although not particularly limited thereto, silicon oxide, aluminum oxide, tantalum oxide, silicon oxynitride, aluminum oxynitride, SiAlON, and the like can be used from the viewpoints of transparency and gas barrier properties. Further, from the viewpoint of acid resistance and alkali resistance, it is preferable that the main component is silicon oxide, nitride or oxynitride.

The gas barrier layer can be produced by a physical vapor deposition (PVD) method such as vapor deposition, ion plating or sputtering, a chemical vapor deposition method such as plasma CVD (chemical vapor deposition), or a sol-gel method. Among these, the sputtering method is preferable because a film having high adhesion, a dense and high gas barrier property is easily obtained. The gas barrier layer can be formed by either a single wafer method or a roll-to-roll method. However, since the film is formed on a plastic film, productivity is improved by the roll-to-roll method. Sputtering deposition of silicon oxide, nitride, or oxynitride includes DC (direct current) sputtering, RF (radio frequency) sputtering, a combination of magnetron sputtering, and dual using an intermediate frequency range. Conventional techniques such as magnetron (DMS) sputtering can be used alone or in combination. In the sputtering atmosphere, an inert gas such as He, Ne, Ar, Kr, and Xe, at least one process gas among oxygen and nitrogen can be used. When sputtering silicon oxide, nitride, or oxynitride by DC sputtering or DMS sputtering, Si can be used as the target. By introducing oxygen or nitrogen into the process gas, a thin film of silicon oxide, nitride or oxynitride can be formed. When these are formed by RF (high frequency) sputtering, a ceramic target such as SiO ₂ or Si ₃ N ₄ can also be used. From the viewpoint of productivity, it is preferable to form a film using Si target and introducing oxygen or nitrogen by DC sputtering or DMS sputtering.

  Two or more gas barrier layers may be provided. In that case, an organic coat layer is preferably provided between the gas barrier layers. Providing this organic coating layer in the intermediate layer is preferable because the gas permeability is reduced as compared with the case where two barrier layers are provided in succession. This is because the organic coating layer covers and smoothes the defects of the barrier layer provided earlier, and the barrier layer provided next is triggered by the defects of the previous barrier layer. It is thought to make it difficult to make. This organic coating layer may also be provided between the plastic film and the gas barrier layer. Each organic coat layer may be the same material or a different material.

  In particular, when this composite material substrate with a transparent electrode is used as a substrate for a color filter, B (black) R (red) G (green) B (formed by a photolithographic method or the like as one of the organic coating layers. A blue colored pattern can also be inserted.

  The organic coating layer is usually a compound having transparency, adhesion and heat resistance, and examples thereof include thermosetting resins such as thermoplastic resins and epoxy resins, and ultraviolet / electron beam crosslinking resins such as acrylic crosslinking resins. However, it is not limited to these. The organic coat layer can be formed by a method such as wire bar, extrusion, microgravure, reverse roll, etc. while keeping the raw material compound in solution, latex or no solvent. The thickness of the organic coating layer is preferably in the range of 0.5 μm to 5 μm from the balance of defect coverage, adhesion, and transparency.

(Transparent electrode layer)

The composite material substrate with a transparent electrode of the present invention includes a transparent electrode layer containing In—Zn—O as a main component.
In one embodiment of the present invention, the transparent electrode layer is deposited on the gas barrier layer. Preferably, the transparent electrode layer is formed directly on the gas barrier layer. When an organic layer exists between the gas barrier layer and the transparent electrode layer, a component (a substance contained in the layer or entering from the edge) due to this layer may enter the liquid crystal element or the organic EL element. In consideration of operability, cost, etching property, etc., ITO and IZO using a sputtering method are practical for this transparent electrode layer. Furthermore, IZO is preferable from the viewpoint of stability of resistance value when subjected to heat treatment, stability of etching characteristics, film stress, and the like. The transparent electrode layer can be formed by either a single wafer method or a roll-to-roll method. However, since the film is formed on a plastic film, the productivity is improved when the roll-to-roll method is used.

The IZO layer is formed by sputtering using conventional techniques such as a DC (direct current) sputtering method, an RF (radio frequency) sputtering method, a method combining this with magnetron sputtering, and a dual magnetron sputtering method using an intermediate frequency region. Can be used alone or in combination. For such film formation, IZO may be used as a target. The IZO target is a material obtained by adding about 5 to 20 wt% of ZnO to In ₂ O ₃ . Since this target has a small bulk resistivity, it is suitable for DC sputtering. In the sputtering atmosphere when forming the IZO film, an inert gas such as He, Ne, Ar, Kr, or Xe, oxygen, or nitrogen can be used. Since oxygen in the formed IZO film is slightly insufficient with respect to the stoichiometric ratio, it is preferable to introduce a small amount of oxygen so as to balance the light transmittance and the specific resistance. The inert gas used at this time is preferably Ar from the viewpoint of economy. Process gas may be introduced while adjusting the flow rate with a mass flow controller. The light transmittance and specific resistance may be adjusted by the introduced gas flow rate while measuring the values in-line.

  As an example of a preferred layer structure for the composite substrate with a transparent electrode of the present invention, (1) organic coating layer / (2) gas barrier layer / (3) plastic film substrate / (4) gas barrier layer / (5) organic coating layer Examples include: / (6) gas barrier layer / (7) IZO electrode.

The water vapor permeability of the composite electrode substrate with a transparent electrode of the present invention is preferably 0.01 g / (m ² · 24 hr) or less (measured value at 40 ° C. and 90% RH based on the JISK7129B method). For example, in order to ensure the light emission lifetime of the organic EL element in a practical time, and to suppress the growth of the non-light-emitting region (dark spot) to an inconspicuous level, the water vapor transmission rate is 0.01 g / (m ² · 24 hr) or less.

  Furthermore, the resistance value of the composite material substrate with a transparent electrode of the present invention is as follows: a is the sheet resistance value of the transparent electrode before being heat-treated at 180 ° C., and b is the sheet resistance value after being heat-treated at 180 ° C. It is preferable that the value of b / a is 0.8 or more and less than 1.5.

  For example, when such a composite substrate with a transparent electrode is used as a substrate for a liquid crystal display, a liquid crystal aligning agent is applied on the transparent electrode, and then usually heat-dried at 180 ° C. or higher. Furthermore, when the composite material substrate with a transparent electrode of the present invention is used for an organic EL substrate, there is usually a washing step with an organic solvent or pure water before forming an organic layer including a light emitting layer. Therefore, it is necessary to sufficiently dry the liquid that has penetrated into the substrate after the cleaning under a heating vacuum. At this time, in order to shorten the exhaust time, the liquid is usually dried at a high temperature of 150 ° C. or higher. That the resistance value does not change in such a heating process is required in terms of the characteristics and yield of the liquid crystal element and the organic EL element.

  In addition, since IZO is amorphous regardless of the heating process, the film stress is small, and there are not only warping of the substrate compared to crystalline ITO etc., but also failure such as fracture due to film stress. Less likely to occur than ITO.

(Organic layer including light emitting layer)
In this invention, after providing a transparent electrode layer and forming a composite material substrate with a transparent electrode, it has a process of forming a planarization layer on a transparent electrode layer, and it is preferable to form an organic layer next.

  When the planarization layer is formed, steep unevenness that may exist on the substrate surface becomes gentle, and leakage current due to concentration of the electric field between the anode and the cathode after the element formation is suppressed. When a voltage is applied to the organic EL element and gradually raised, the first short-circuited part is the part where the electric field concentrates. Therefore, when the planarization layer is formed, the element is not easily burned even if the area is increased. The yield of light emission is improved.

  As the planarization layer, a conductive material can be widely used. However, a material in which charges are easily injected from an electrode and a molecule having a flat plate shape and easy to stack is preferable. Phthalocyanine-based materials are preferable, and copper phthalocyanines (CuPC) are particularly preferable. The planarization layer can be formed by a method such as vapor deposition, sputtering, or chemical vapor deposition (CVD) in vacuum.

  The thickness of the planarizing layer is preferably 1 nm to 50 nm. If it is thicker than 50 nm, the light emission voltage increases and the power efficiency decreases. If the thickness is less than 1 nm, the unevenness of the surface of the substrate cannot be sufficiently hidden, and when a voltage is applied to the completed device, the leakage current increases and the possibility of damage due to current concentration increases.

  In addition, since it demonstrates in detail later about the organic layer in this invention, it abbreviate | omits here.

(Counter electrode)
The organic electroluminescence device of the present invention includes a counter electrode on an organic layer including a light emitting layer.
The counter electrode normally functions as a cathode. As the cathode, a material having a small work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof is used. Preferably used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (A1 ₂ 0 ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like.

Among these, a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value than this from the viewpoint of durability against electron injecting and oxidation, for example, a magnesium / silver mixture, magnesium An aluminum / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (A1 ₂ 0 ₃ ) mixture, a lithium / aluminum mixture and the like are suitable.

  The cathode can be produced by forming a thin film from these electrode materials by a method such as vapor deposition or sputtering. Alternatively, the sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 1 μm, preferably 50 nm to 200 nm. In order to transmit light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the light emission efficiency is improved, which is convenient.

(Sealing can)
In this invention, it seals on each layer (on a counter electrode) which comprises the said organic EL element formed on the translucent board | substrate in this way using another sealing member.

The sealing member may be formed of glass, resin, ceramic, metal, metal compound, or a composite thereof. In a test based on JIS Z-0208, the thickness is 1 μm or more and the water vapor transmission rate. Is preferably 1 g / (m ² · 24 hr) (1.013 × 10 ⁻¹ MPa, 25 ° C.) or less.

  Moreover, it is also preferable to use the light-transmitting plastic film substrate according to the present invention. By making both the substrates low in moisture permeability and highly flexible, an organic EL element resistant to impact can be formed. The present invention can also be applied to a surface light source whose light emitting surface is a curved surface.

  In addition, the sealing member (glass, film, etc.) on the counter electrode side (cathode, eg, Al, Mg electrode side) is sealed in order to prevent electroluminescence from being absorbed or light from diffusing to the back side. It is preferable to form a pigment layer filled with white titanium oxide on the surface of the member facing the cathode (Al, Mg, etc.) side.

  Sealing is performed through a substantially frame-shaped adhesive layer (or sealing material) provided by a coating method, a transfer method, or the like on the periphery of the surface of the sealing member facing, for example, the counter cathode (upper electrode) side. This is performed by pasting together the transparent substrates on which the respective layers of the organic EL elements facing each other are formed.

For the adhesive layer, a thermosetting epoxy resin, an ultraviolet curable epoxy resin, or a room temperature curable epoxy resin in which a reaction starts by microencapsulating and pressurizing a reaction initiator can be used. In this case, an air escape opening or the like is provided at a predetermined portion of the adhesive layer (not shown) to complete the sealing. The air escape opening is one of the above curable epoxy resins in a reduced pressure atmosphere (preferably a degree of vacuum of 1.33 × 10 ⁻² MPa or less) in a vacuum apparatus, or in a nitrogen gas or inert gas atmosphere, or Sealed with an ultraviolet curable resin or the like.

  Examples of epoxy resins include bisphenol A, bisphenol F, bisphenol AD, bisphenol S, xylenol, phenol novolac, cresol novolac, polyfunctional, tetraphenylolmethane, polyethylene glycol, polypropylene A glycol type, hexanediol type, trimethylolpropane type, propylene oxide bisphenol A type, hydrogenated bisphenol A type, or a mixture thereof is mainly used.

  In addition, a material that absorbs moisture or reacts with moisture (for example, barium oxide or the like) can be formed in a layer on the substrate and sealed.

(Constitution layers and dopants of organic EL elements)
In the present invention, the organic layer only needs to have a light emitting layer, and the light emitting layer in a broad sense is a layer that emits light when a current is passed through an electrode composed of a cathode and an anode, Specifically, it refers to a layer containing a compound that emits light when an electric current is passed through an electrode composed of a cathode and an anode.

In the present invention, the light emitting layer is obtained by adding a phosphorescent material (hereinafter also referred to as a phosphorescent compound) as a dopant to a light emitting layer host (hereinafter also referred to as a host compound) which is a main material of the light emitting layer.
In the present invention, a preferable organic layer is one in which a light emitting layer is provided between the first layer and the second layer having different functions such as hole transport property and electron transport property.

In general, when there are two or more materials constituting the light emitting layer, the main component is called a host compound, and the other components are called dopants. In the present invention, the above phosphorescent dopant is used.
In that case, the mixing ratio of the dopant to the host compound as the main component is preferably 0.1% by mass to less than 15% by mass.

(Host compound)
In the organic electroluminescent device of the present invention, as the host compound, any known compound used for the organic EL device may be selected and used. Most of the above hole transport materials and electron transport materials can also be used as the light emitting layer host compound.
The host compound is preferably an organic compound or a complex. For example, a polymer material may be used, and a polymer material in which the host compound is introduced into a polymer chain or the host compound is a polymer main chain may be used.
Examples of the light-emitting host (host compound) include materials including a partial structure such as a carbazole derivative, a biphenyl derivative, a styryl derivative, a benzofuran derivative, a thiophene derivative, and an arylsilane derivative as a unit. Of these, a carbazole derivative and a biphenyl derivative are preferable light emitting materials exhibiting high light emission efficiency.
As the host compound, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

(Dopant)
In recent years, Princeton University has reported an organic EL device using phosphorescence emission from an excited triplet (MA Baldo et al., Nature, 395, 151-154 (1998)), from an excited singlet. Compared with organic EL devices using fluorescent light emission, the luminous efficiency is four times as much in principle and has been attracting attention. Also in the present invention, it is preferable in terms of luminous efficiency that a phosphorescent compound (dopant) is contained.

  The phosphorescent compound in the present invention is a compound in which light emission from an excited triplet is observed, and is a compound having a phosphorescence quantum yield of 0.001 or more at 25 ° C. The phosphorescent quantum yield is preferably 0.01 or more, more preferably 0.1 or more.

  The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 version, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence quantum yield used in the present invention is only required to achieve the above phosphorescence quantum yield in any solvent.

  There are two types of principle of the dopant. One is the recombination of the carrier on the host where the carrier is transported to generate an excited state of the host compound, and this energy is transferred to the dopant to emit light from the dopant. The other is a carrier trap type in which the dopant becomes a carrier trap, and carrier recombination occurs on the dopant compound, and light emission from the dopant is obtained. The condition is that the excited state energy of is lower than the excited state energy of the host compound.

  In the organic electroluminescence device of the present invention, the phosphorescent compound used as a dopant is preferably a complex compound containing a Group VIII metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, Or it is a platinum compound (platinum complex compound), and an iridium compound is the most preferable among them.

  Specific examples of the phosphorescent compound used in the present invention are shown below, but are not limited thereto. These compounds are described, for example, in Inorg. Chem. 40, 1704-1711, and the like. Note that the phosphorescent compound contained may or may not have a polymerizable functional group or a reactive functional group.

  The organic layer of the present invention preferably has a hole transport layer, an electron transport layer, an anode buffer layer, a cathode buffer layer, and the like in addition to the light emitting layer, and is sandwiched between the cathode and the anode.

  Specific structures of the organic layer include the structures shown below.

(I) Anode / hole transport layer / light emitting layer / cathode (ii) Anode / light emitting layer / electron transport layer / cathode
(Iii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iv) Anode / anode buffer layer / hole transport layer / light emitting layer / electron transport layer / cathode buffer layer / cathode

(Light emitting layer)
The light emitting layer according to the organic EL device of the present invention will be described.

  The light-emitting layer is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer. It may be an interface with an adjacent layer.

  As the formation method, for example, a thin film can be formed by a known method such as a vapor deposition method, a spin coating method, a casting method, or an LB method. In the present invention, the vapor deposition method is particularly preferable.

  In general, it is preferable that the light emitting layer is disposed on the cathode side of the hole transport layer from the viewpoint of the performance of the device. Therefore, compared with the hole transport material, all the materials used for the light emitting layer are relatively (definition of the present invention). So it becomes an electron transport material.

  In the present invention, when referring to a hole transport material and an electron transport material, a material having a higher highest occupied molecular orbital (HOMO) level (close to the vacuum order) is the hole transport. The material is defined as the electron transport material.

(Film thickness of the light emitting layer)
There is no restriction | limiting in particular about the film thickness of the light emitting layer formed in this way, Although it can select suitably according to a condition, It is preferable to adjust film thickness in the range of 5 nm-5 micrometers.

  Next, other layers constituting the organic EL element in combination with the light emitting layer, such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer, will be described.

(Hole injection layer, hole transport layer, electron injection layer, electron transport layer)
The hole injection layer and hole transport layer used in the present invention have a function of transmitting holes injected from the anode to the light emitting layer, and the hole injection layer and hole transport layer serve as the anode and the light emitting layer. Therefore, many holes are injected into the light emitting layer with a lower electric field, and electrons injected from the cathode, the electron injection layer, or the electron transport layer into the light emitting layer are positively connected to the light emitting layer. Due to an electron barrier existing at the interface of the hole injection layer or the hole transport layer, it is accumulated at the interface in the light emitting layer, and the light emitting efficiency is improved.

(Hole injection material, hole transport material)
The material of the hole injection layer and hole transport layer (hereinafter referred to as hole injection material and hole transport material) has the property of transmitting holes injected from the anode to the light emitting layer. If it is a thing, there will be no restriction | limiting in particular, In a photoconductive material, what is conventionally used as a charge injection transport material of a hole, and the well-known thing used for the hole injection layer of a EL element, a hole transport layer are used. Any one can be selected and used.

  The hole injection material and the hole transport material have any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. Examples of the hole injection material and hole transport material include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, virazoline derivatives and virazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazoles. Derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, or conductive polymer oligomers, particularly thiophene oligomers. As the hole injecting material and the hole transporting material, those described above can be used, and porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds, particularly aromatic tertiary amine compounds can be used. preferable.

  Representative examples of the aromatic tertiary amine compound and styrylamine compound include N, N, N ′, N ′ monotetraphenyl-4,4′-diaminophenyl; N, N′-diphenyl-N, N ′. -Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-P-tolylaminophenyl) propane; Bis (4-di-P-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-P-tolyl 4,4′-diaminobiphenyl; 1,1-bis (4-di-P -Tolylaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-P-tolylaminophenyl) phenylmethane; N, N'-diphenyl- N, N'-di (4-meth Cyphenyl) -4,4′-diaminobiphenyl; N, N, N ′, N′-tetraphenyl-4,4′-diaminodiphenyl ether; 4,4′-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-P-tolylamino) -4 ′-[4- (di-P-tolylamino) styryl] stilpene; 4-N, N-diphenylamino- (2-diphenyl) Vinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and two fused aromatic rings described in US Pat. No. 5,061,569. What is contained in the molecule, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD), described in JP-A-4-308688 4,4 triphenylamine units there are connected to three star Perth preparative ', 4 "- tris [N- (3- methylphenyl) -N- phenylamino] triphenylamine (MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  Alternatively, inorganic compounds such as P-type-Si and P-type-SiC can also be used as the hole injection material and the hole transport material. The hole injection layer and the hole transport layer are formed by thinning the hole injection material and the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. Can be formed.

(Hole injection layer thickness, hole transport layer thickness)
Although there is no restriction | limiting in particular about the film thickness of a positive hole injection layer and a positive hole transport layer, It is preferable to adjust to the range about 5 nm-5 micrometers. The hole injection layer and hole transport layer may have a single layer structure composed of one or more of the above materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions.

(Electron transport layer, electron transport material)
The electron transport layer according to the present invention is only required to have a function of transmitting electrons injected from the cathode to the light emitting layer, and as the material thereof, any one of conventionally known compounds can be selected and used. Can do.

  Examples of materials used for this electron transport layer (hereinafter referred to as electron transport materials) include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiobilane dioxide derivatives, heterocyclic tetracarponic anhydrides such as naphthalene perylene, carposimide, fluoreni Examples include redenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, and organometallic complexes. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  Or metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum, tris (2-Methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metals of these metal complexes are In, Mg, Cu, Metal complexes replaced with Ca, Sn, Ga, or Pb can also be used as the electron transport material.

  In addition, metal-free or metal phthalocyanine, and those having the terminal substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transport material. Alternatively, the distyrylvirazine derivative exemplified as the material for the light-emitting layer can also be used as an electron transport material, and like the hole injection layer and the hole transport layer, n-type-Si, n-type-SiC, and the like can be used. Inorganic semiconductors can also be used as electron transport materials.

  The electron transport layer can be formed by forming the above compound by a known thin film forming method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method.

(Film thickness of electron transport layer)
Although the film thickness of an electron carrying layer does not have a restriction | limiting in particular, It is preferable to adjust to the range of 5 nm-5 micrometers. This electron transport layer may have a single layer structure composed of one or two or more of these electron transport materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions.

  Further, in the present invention, the fluorescent compound is not limited to the light emitting layer, but is the same as the fluorescent compound that becomes the host compound of the phosphorescent compound in the hole transport layer adjacent to the light emitting layer or the electron transport layer. At least one fluorescent compound having a fluorescent maximum wavelength in the region may be contained, whereby the luminous efficiency of the EL element can be further increased. As the fluorescent compound contained in these hole transport layer and electron transport layer, the fluorescent compound having a fluorescence maximum wavelength in the range of 350 nm to 440 nm, more preferably 390 nm to 410 nm, as in the light emitting layer. A compound is used.

  Next, a suitable example for producing an organic EL element having an organic layer will be described. As an example, a method for manufacturing an EL element composed of the anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described.

  First, a thin film made of a desired electrode material, for example, an anode material is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 to 200 nm. An anode is produced. Next, a thin film comprising a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer / electron injection layer, which is a device material, is formed thereon.

  Further, a buffer layer (electrode interface layer) may be present between the anode and the light emitting layer or hole injection layer and between the cathode and the light emitting layer or electron injection layer.

  The buffer layer is a layer provided on the electrode and the organic layer for lowering the driving voltage and improving the luminous efficiency. “The organic EL element and its forefront of industrialization (November 30, 1998, NTS Corporation) The details are described in Chapter 2 “Electrode Materials” (pages 123 to 166) of the 2nd volume of “Summary”), and there are an anode buffer layer and a cathode buffer layer.

  The details of the anode buffer layer are also described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, a phthalocyanine buffer layer represented by copper phthalocyanine And an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

  The details of the cathode buffer layer are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like, specifically, metals represented by strontium, aluminum and the like. Examples include a buffer layer, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, an oxide buffer layer typified by aluminum oxide and lithium oxide, and the like.

  The buffer layer is preferably a very thin film, and depending on the material, the film thickness is preferably in the range of 0.1 to 100 nm.

  Further, in addition to the above basic constituent layers, layers having other functions may be laminated as required. For example, JP-A-11-204258, JP-A-11-204259, and “Organic EL elements and their industrialization It may have a functional layer such as a hole blocking layer described on page 237 of the front line (published on November 30, 1998 by NTT).

  The method for producing the organic EL device according to the present invention has been described above, but a supplementary explanation will be given below.

As the thinning method, there are a spin coating method, a casting method, a vapor deposition method and the like as described above, but a vacuum vapor deposition method is preferable because a homogeneous film can be easily obtained and pinholes are hardly generated. When the vacuum deposition method is adopted for thinning, the deposition conditions vary depending on the type of compound used, the target crystal structure of the molecular deposition film, the association structure, etc., but generally the boat heating temperature is 50 to 450 ° C., the degree of vacuum It is desirable to select appropriately within a range of 10 ⁻⁶ to 10 ⁻³ Pa, a deposition rate of 0.01 nm / second to 50 nm / second, a substrate temperature of −50 ° C. to 300 ° C., and a film thickness of 5 nm to 5 μm.

  As described above, a desired electrode material, for example, a thin film made of an anode material is formed on the plastic film substrate by a method such as vapor deposition or sputtering, and then an anode is prepared. Then, holes are injected onto the anode as described above. After forming each layer thin film composed of a layer, a hole transport layer, a light emitting layer, an electron transport layer / electron injection layer, a thin film composed of a cathode material is formed thereon by a method such as vapor deposition or sputtering, for example. A desired organic EL element can be obtained.

  Hereinafter, the present invention will be described in more detail with reference to examples. In the following embodiments, a reference numeral is appended to the layer in order to distinguish the plurality of layers. In the same embodiment, the same reference numerals represent the same layer.

(Example 1)
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The following glass fiber is impregnated with the following polyfunctional acrylate resin composition (refractive index after cross-linking: 1.531), and then continuously cured by an ultraviolet curing device, resin 50% by weight, glass fiber 50% by weight, width 30 cm, long A plastic film (1) having a thickness of 100 m and a thickness of 100 μm was obtained.

<Polyfunctional acrylate resin composition>
Dicyclopentadienyl diacrylate (Formula 1)
(M-203 manufactured by Toagosei Co., Ltd., refractive index 1.527 after crosslinking) 96 parts by weight Bis [4- (acryloyloxyethoxy) phenyl] fluorene (Formula 4)
(Toagosei Co., Ltd. prototype TO-2065, refractive index after crosslinking 1.624) 4 parts by weight Photopolymerization initiator 1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by Ciba Specialty Chemicals, Irgacure 184) 0.5 weight Part

<Glass fiber>
S glass-based glass cloth (thickness 50 μm, refractive index 1.530, manufactured by Unitika cloth (# 2117))

  The obtained plastic film (1) had a linear expansion coefficient of 10 ppm at 30 ° C. to 150 ° C.

  Further, the glass transition temperature of the plastic film (1) was 250 ° C. or higher as evaluated by tan δmax. The total light transmittance of this plastic film (1) was 90.9%.

(Production of gas barrier layer)
This plastic film (1) is loaded into a sputter roll coater, and by DC magnetron sputtering, using Si as a target, the ultimate vacuum is 1.0 × 10 ⁻⁴ Pa or less, and the film forming temperature is 180 ° C. Argon gas and oxygen gas were introduced, and a 70 nm-thick SiOx film (x = 1.8, using XPS) was formed on the plastic film (1) by reactive sputtering to form a gas barrier layer (2).

  Next, 100 parts by weight of an epoxy acrylate prepolymer, 200 diethylene glycol are used on a continuous coating machine equipped with a roll unwinding device, a micro gravure coater, a drying furnace, a UV irradiation device, and a roll winding device on the gas barrier layer (2). A homogeneous mixed solution of parts by weight, 100 parts by weight of ethyl acetate, 2 parts by weight of benzene ethyl ether, and 1 part by weight of a silane coupling agent was applied with a micro gravure coater of a continuous coating machine and passed through a drying zone at 120 ° C. Thereafter, ultraviolet rays were irradiated to form an organic coat layer (3) having a thickness of 3 μm.

Next, in order to form a gas barrier layer (4) on the surface opposite to the organic coat layer (3), the plastic film (1) on which the organic coat layer (3) is formed is loaded into a sputter roll coater, and DC Using magnetron sputtering, Si is used as a target, an ultimate vacuum of 1.0 × 10 ⁻⁴ Pa or less, a film formation temperature of 180 ° C., argon gas and oxygen gas are introduced as process gases, and SiOx having a film thickness of 70 nm is formed by reactive sputtering. A gas barrier layer (4) was formed by forming a film (x = 1.8, by XPS).

(Preparation of IZO layer)
Finally, in order to form the IZO layer (5), the plastic film (1) on which the gas barrier layer (4) is formed is loaded into a sputter roll coater, and DC magnetron sputtering is performed to obtain 10 wt. Of ZnO in IZO (In ₂ O _3). %) Was used as a target, and an argon gas and a small amount of oxygen gas were introduced as a process gas at a film forming temperature of 100 ° C., and an IZO film having a film thickness of 150 nm was formed by reactive sputtering to form an IZO layer (5). (Evaluation board 1-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the evaluation substrate 1-1 based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less.

(Preparation of organic EL element evaluation substrate)
In order to evaluate the dark spot (DS) generation rate (%) of the composite substrate with a transparent electrode, an organic EL device was produced. In this case, under the same conditions as the formation of the IZO layer (5) described above, a portion where the IZO layer (5) was not sputtered was simultaneously formed using a shadow mask, and the shape of the electrode when energized was created on the substrate. .

  The pattern-formed composite material substrate with a transparent electrode was cut into 30 mm square pieces using a laser cutter (carbon dioxide laser: energy 30 W).

  This plastic substrate with an IZO pattern was sequentially washed with pure water, 5% surfactant aqueous solution, aqueous ammonia hydrogen peroxide, and isopropyl alcohol (IPA), and dried at 180 ° C. for 5 hours in a clean nitrogen atmosphere (evaluation). Substrate 1-2).

(Production of green phosphorescent organic EL device)
Next, as shown in FIG. Phys. Lett. , Vol. 81, no. A green phosphorescent organic EL device was produced according to 16, 14 October 2002, p2929. The ultimate vacuum before vapor deposition was 3 × 10 ⁻⁵ Pa. On the evaluation board | substrate 1-2 of this invention, copper phthalocyanine (CuPC) was vapor-deposited 10 nm as a planarization layer (not shown), and the organic layer (6) was formed on it.

On the planarizing layer, a hole transport material α-NPD was vacuum-deposited by 30 nm, and a light-emitting layer host CBP and a light-emitting layer dopant Ir (ppy) ₃ were formed by co-evaporation of 30 nm (Ex. Ir-1) (Ir -1 is 6 wt% with respect to CBP). Then BAlq as the hole blocking material, was deposited to the electron transporting material Alq ₃ to a thickness of each 10 nm, 40 nm, to manufacture an organic layer.

  On top of that, LiF was deposited to 1 nm and aluminum was deposited to 100 nm as a counter electrode (7) to form a multilayer element.

  This element was bonded using a stainless steel sealing can (8) and an ultraviolet curable adhesive (9) in a nitrogen atmosphere.

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED1.

      Hole transport material

      Light emitting layer host

Light emitting layer dopant Ir (ppy) ₃

      Hole blocking material BAlq

      Electron transport material

(Example 2)
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the organic coat layer (10) in the same manner as in Example 1.

(Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (11) in the same manner as in Example 1 (evaluation substrate 2-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained evaluation board 2-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 2-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED2.

(Example 3)
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the surface opposite to the organic coat layer (3) by the same method as in Example 1.
An organic coat layer (12) was formed on the gas barrier layer (11) in the same manner as in Example 1.
A gas barrier layer (13) was formed on the organic coat layer (12) in the same manner as in Example 1. (Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (13) in the same manner as in Example 1 (evaluation substrate 3-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 3-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 3-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED3.

Example 4
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
An organic coat layer (14) was formed on the plastic film (1) in the same manner as in Example 1.
The organic coating layer (15) was formed on the opposite surface of the organic coating layer (14) in the same manner as in Example 1.
A gas barrier layer (16) was formed on the organic coat layer (15) in the same manner as in Example 1.
An organic coat layer (17) was formed on the gas barrier layer (16) in the same manner as in Example 1.
A gas barrier layer (18) was formed on the opposite surface of the organic coating layer (17) by the same method as in Example 1.
An organic coat layer (19) was formed on the gas barrier layer (18) in the same manner as in Example 1.
A gas barrier layer (20) was formed on the organic coat layer (19) in the same manner as in Example 1.
(Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (20) in the same manner as in Example 1 (evaluation substrate 4-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 4-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 4-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED4.

(Example 5)
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.

(Preparation of IZO layer)
An IZO layer (5) was formed on the organic coat layer (10) in the same manner as in Example 1 (evaluation substrate 9-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The substrate used for producing the organic EL element was subjected to pattern formation, cutting, washing and drying in the same manner as in Example 1 to obtain an evaluation substrate 9-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 9-2 of the present invention, and a stainless steel can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED9.

(Comparative example 1 (no transparent electrode 1))
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite material substrate formed up to the gas barrier layer (4) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less.

(Comparative example 2 (no transparent electrode 2))
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the organic coat layer (10) in the same manner as in Example 1.

When the water vapor permeability at 40 ° C. and 90% RH was measured on the composite material substrate formed up to the gas barrier layer (11) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less.

(Comparative Example 3 (ITO))
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.

(Preparation of ITO layer)
Finally, in order to form the ITO layer (21), the plastic film (1) on which the gas barrier layer (4) is formed is loaded into a sputtering roll coater, and ITO (added 10 wt% of SnO2 to In2O3) by DC magnetron sputtering. As a target, an argon gas and a small amount of oxygen gas were introduced at a film forming temperature of 100 ° C., and an ITO film having a film thickness of 150 nm was formed by reactive sputtering to form an ITO layer (21) (Evaluation substrate 5- 1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured on the composite substrate with a transparent electrode formed up to the ITO layer (21) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 5-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 5-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to this device with the ITO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED5.

(Comparative Example 4 (ITO))
(Production of glass sheet containing glass fiber-containing crosslinked resin)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the organic coat layer (10) in the same manner as in Example 1.

(Preparation of ITO layer)
An ITO layer (21) was formed on the gas barrier layer (11) in the same manner as in Comparative Example 3 (evaluation substrate 6-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured on the composite substrate with a transparent electrode formed up to the ITO layer (21) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 6-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarization layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 6-2 of the present invention, and a stainless steel can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to this device with the ITO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED6.

(Comparative Example 5 (PES substrate))
(Preparation of plastic film)
As the plastic film, a polyethersulfone (PES) film FST-U1340 (manufactured by Sumitomo Bakelite Co., Ltd.) having a width of 30 cm, a length of 100 m, and a thickness of 200 μm was used. This film was designated as a plastic film (2).

(Production of gas barrier layer)
A gas barrier layer (2) was formed on the plastic film (2) in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the organic coat layer (10) in the same manner as in Example 1.

(Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (11) in the same manner as in Example 1 (evaluation substrate 7-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 7-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 7-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED 7.

(Comparative Example 6 (PES substrate, ITO))
(Preparation of plastic film)
The same plastic film (2) as in Comparative Example 5 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed on the plastic film (2) in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (4) was formed on the opposite surface of the organic coating layer (3) in the same manner as in Example 1.
On this gas barrier layer (4), an organic coat layer (10) was formed in the same manner as in Example 1.
A gas barrier layer (11) was formed on the organic coat layer (10) in the same manner as in Example 1.

(Preparation of ITO layer)
An ITO layer (21) was formed on the gas barrier layer (11) in the same manner as in Comparative Example 3 (evaluation substrate 8-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured on the composite substrate with a transparent electrode formed up to the ITO layer (21) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 8-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 8-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to this device with the ITO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED8.

(Comparative Example 7 (single-sided barrier))
(Production of glass fiber-containing crosslinked resin-containing plastic film)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.

(Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (2) in the same manner as in Example 1 (evaluation substrate 10-1).

When the water vapor permeability at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.02 g / (m ² · 24 hr). It was.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 10-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarizing layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 10-2 of the present invention, and a stainless steel can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED 10.

(Comparative Example 8 (single-sided barrier))
(Production of glass sheet containing glass fiber-containing crosslinked resin)
The plastic film (1) of Example 1 was used.

(Production of gas barrier layer)
A gas barrier layer (2) was formed in the same manner as in Example 1.
An organic coat layer (3) was formed in the same manner as in Example 1.
A gas barrier layer (22) was formed on the organic coat layer (3) in the same manner as in Example 1.

(Preparation of IZO layer)
An IZO layer (5) was formed on the gas barrier layer (22) in the same manner as in Example 1 (evaluation substrate 11-1).

When the water vapor transmission rate at 40 ° C. and 90% RH was measured for the composite substrate with a transparent electrode formed up to the IZO layer (5) as described above based on the JISK7129B method, it was 0.01 g / (m ² · 24 hr) or less. there were.

(Preparation of organic EL element evaluation substrate)
The board | substrate used for organic EL element preparation performed pattern formation, a cutting | disconnection, washing | cleaning, and drying similarly to Example 1, and obtained the evaluation board | substrate 11-2.

(Production of green phosphorescent EL element)
As in Example 1, a planarization layer, an organic layer (6) and a counter electrode (7) are formed on the evaluation substrate 11-2 of the present invention, and a stainless steel sealing can (8) and an ultraviolet curable adhesive ( 9).

  Barium oxide was added as a dehydrating agent between the sealing can and the element. When a voltage of 10 V was applied to the device with the IZO side being positive and the aluminum side being negative, green light emission having a peak wavelength of 510 nm was observed. This element is referred to as OLED 11.

(Evaluation of composite material substrate with transparent electrode)
The composite material substrate with a transparent electrode obtained by the following method was evaluated. The results are shown in Table 1.

(Water vapor transmission rate (WVTR))
Based on the JISK7129B method, the water vapor transmission rate at 40 ° C. and 90% RH was measured.

(Durability / Dark spot growth)
After driving OLEDs 1 to 11 at a constant current of 10 mA / cm ² for 500 hours under conditions of 25 ° C. and 50% RH, the area of the non-light emitting point (dark spot) that can be confirmed in the range of 6 mm × 15 mm square is measured. did.

(Luminescence yield)
Ten elements of each of the examples and comparative examples were produced in the same manner, and those in which current flowed at the first energization immediately after the trial production and emitting light entirely were regarded as non-defective products, and those that did not emit light entirely were regarded as defective products. The number of non-defective products out of 10 is shown.

(Resistance value / resistance value change)
Based on the JISK7194 method, five points were measured for each sample to determine the surface resistivity (Ω / □). The thickness of each transparent electrode layer is 150 nm. For the evaluation sample, the evaluation substrate of -1 of the example and the comparative example is used (for example, the evaluation substrate 1-1 is used in the case of the example 1). It was measured.

(Linear expansion coefficient)
According to JIS K7197, the linear expansion coefficient of the plastic film was measured using a TMA / SS120C type thermal stress strain measuring device manufactured by Seiko Denshi Co., Ltd.

(Light transmittance)
The total light transmittance was measured based on the JIS K 7361 method. As an evaluation sample, the evaluation substrate of -1 of Examples and Comparative Examples was used (for example, in the case of Example 1, the evaluation substrate 1-1 was used).

(Board warpage)
Evaluation substrate-2 (e.g., evaluation substrate 1-2 was used in Example 1) was visually observed immediately after the drying step. If there was little warpage (approximately 3 mm or less), it was marked as ◯.

  As is apparent from Table 1, the composite substrate with a transparent electrode of the present invention is excellent in dimensional stability, gas barrier properties, transparency and heat resistance, stable in resistance, and easy to handle with little warping of the substrate. Therefore, the yield when the organic EL element is made is high, and dark spots can be suppressed.

  From Examples 1 and 2 and Comparative Examples 1 and 2, the substrate of the present invention has a high gas barrier property before and after IZO film formation. Next, comparing the dark spot area ratios of Examples 1 and 2 and Comparative Examples 3 and 4, it can be seen that IZO is superior to ITO in this characteristic. Furthermore, if the number of barrier layers and smoothing coat layers is increased as shown in Examples 3 and 4, dark spots can be further suppressed.

  When Example 2 and Comparative Example 5 are compared, Example 2 is superior in light emission yield and substrate warpage. This is considered to be due to the difference in the coefficient of linear expansion of the substrate. It is considered that the plastic film (1) with less movement of the substrate during the process is excellent. The small movement of the substrate during the process is not limited to the contents of this embodiment, but is also advantageous when used for an active matrix display substrate. Further, although details are unknown, Example 2 gave excellent results even in the dark spot area ratio.

  When Example 2 was compared with Comparative Example 6, not only the light emission yield and the warpage of the substrate, but also a significant difference in the dark spot area ratio was found. Since the dark spot area ratio of Comparative Example 6 was much larger than expected, the central portion of the dark spot was FIB cut, and TEM observation was performed. As a result, a plurality of forms in which the ITO and the SiOx layer immediately below were continuously broken were observed. It is presumed that this was caused by the interaction between the expansion and contraction of the substrate and the internal stress of ITO in the processes after the ITO film formation.

  In Comparative Example 7 in which the barrier layer is provided on only one layer on one side, the barrier property is insufficient. Further, in Comparative Example 8 in which two barrier layers are provided on one side, the warpage of the substrate is large, and the yield is poor when an organic EL element is used.

  Finally, when the IZO electrodes of Examples 1 to 5 and Comparative Examples 5, 7, and 8 and the ITO electrodes of Comparative Examples 3, 4, and 6 were compared, the resistance value changed even when IZO was processed at a temperature of 180 ° C. In contrast, the resistance value of ITO varies greatly after heat treatment. This is presumably due to the fact that IZO is amorphous before and after the treatment, whereas ITO is crystallized. In any case, IZO has been shown to be advantageous when considering process stability on these plastic films.

Schematic sectional view showing an example of an organic EL element

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plastic film 2 Gas barrier layer 3 Organic coat layer 4 Gas barrier layer 5 IZO electrode 6 Organic layer 7 Counter electrode 8 Stainless steel sealing can 9 Adhesive 10 Organic EL element

Claims (8)

An organic electroluminescence device comprising a composite material substrate with a transparent electrode and a light emitting layer,
The composite substrate with a transparent electrode is
A plastic film containing a crosslinked resin and glass fiber;
At least one gas barrier layer provided on both sides of the plastic film;
A transparent electrode layer provided on the gas barrier layer and containing In-Zn-O as a main component;
An organic electroluminescence device comprising:   The organic light-emitting device according to claim 1, wherein the light-emitting layer includes a light-emitting layer host and a phosphorescent material.   The organic electroluminescent element according to claim 1 or 2, wherein the glass fiber is blended in an amount of 10 to 90% by weight based on the total weight of the plastic film.   The organic electroluminescent element according to any one of claims 1 to 3, wherein the plastic film has a linear expansion coefficient at 30 to 150 ° C of 0 ppm / ° C or more and 40 ppm / ° C or less. The water vapor permeability of the composite substrate with a transparent electrode is 0.01 g / (m ² · 24 hr) or less (measured value at 40 ° C. and 90% RH based on the JISK7129B method). 5. The organic electroluminescence device according to any one of 4 above.   In the composite substrate with a transparent electrode, when the sheet resistance value of the transparent electrode before heat treatment at 180 ° C. is a and the sheet resistance value of the transparent electrode after heat treatment at 180 ° C. is b, b / a A value is 0.8 or more and less than 1.5, The organic electroluminescent element of any one of Claims 1-5 characterized by the above-mentioned.   The organic electroluminescence device according to any one of claims 1 to 6, wherein the gas barrier layer contains a silicon oxide, nitride, or oxynitride as a main component.   The organic electroluminescent element according to claim 1, wherein the composite substrate with a transparent electrode further includes an organic coat layer.

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