JP2016091793A - Organic electroluminescent device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent device excellent in durability and folding resistance under a high-temperature and high-humidity environment even having a narrow bezel width by a side face sealing technique of an organic electroluminescent element that comprises a flexible member, and a method for manufacturing the organic electroluminescent device.SOLUTION: An organic electroluminescent device of the present invention includes a laminate in which at least an organic electroluminescent element unit and a flexible sealing plate are laminated in the order on a flexible substrate, and also includes a side face sealing layer on a side face part of a laminate that comprises at least the organic electroluminescent element unit and the flexible sealing plate. The side face sealing layer is formed of a polymer having a surface energy of 30×10N/m or less, as a main component thereof.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an organic electroluminescent device and a method for manufacturing the same, and more particularly, to an organic electroluminescent device excellent in bending durability and a method for manufacturing the same.

  Currently, as a thin light emitting device, an organic electroluminescence element (hereinafter also referred to as an organic EL element) using electroluminescence of an organic material (hereinafter referred to as “EL”) is several V to several. It is a thin-film type complete solid-state device that can emit light at a low voltage of about 10 V, and has many excellent features such as high brightness, high luminous efficiency, thinness, and light weight. It attracts attention as a surface light emitter such as a display board such as an emergency light or an illumination light source.

  An organic EL device has a structure in which an organic functional layer group including a light emitting layer containing a light emitting compound is sandwiched between a cathode and an anode, and excitons are injected by recombination by injecting electrons and holes into the light emitting layer. Is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when this exciton is deactivated, and can emit light at a voltage of about several volts to several tens of volts. In recent years, an organic EL element having flexibility by using a flexible substrate, for example, a resin film, thin film glass, or the like has been used in a wide field by taking advantage of its characteristics.

  The flexible organic EL element as described above, for example, is produced in a single-wafer state by cutting into a predetermined size in the next step after continuously producing a long organic EL element laminate by a roll-to-roll method. Often done.

  In the organic EL element cut into such a sheet shape, each side surface is exposed, so that moisture and oxygen enter from the side surface portion, and organic functionality including a light emitting layer having low resistance to them. By deactivating the material, there arises a problem that the light emitting failure region is enlarged from the side surface portion.

  To solve the above problem, a method has been proposed in which a sealing member for preventing intrusion of moisture and oxygen is provided on the side surface exposed by cutting.

  Consists of a flexible substrate layer, an organic EL element layer, and a flexible sealing layer, and a polymer (for example, polyvinyl alcohol, polyimide, polyamide, etc.) and inorganic particles (for example, silicon dioxide, titanium oxide, etc.) on the side surface of the organic EL device By providing a side sealing layer containing, and setting the linear expansion coefficient of the side sealing layer between the respective linear expansion coefficients of the flexible substrate and the flexible sealing layer, both curl resistance and flexibility can be achieved. Has been disclosed (for example, see Patent Document 1). However, if the bezel at the end of the organic EL element forming the side sealing portion (the frame portion provided around the display portion) is narrowed, the sealing performance of the sealing material is insufficient, and oxygen and moisture from the external environment Have the problem of being easily affected.

  Further, as a side sealing method in a liquid crystal display element, a method is disclosed in which a moisture-proof portion is provided on the outer peripheral portion of a seal portion for fixing a plurality of constituent members, and the moisture-proof portion contains a fluorine-based resin and porous silicon dioxide. (For example, refer to Patent Document 2). However, in Patent Document 2, the target is a liquid crystal display element, and even if the effect is sufficient for the liquid crystal display element, the organic EL element is required to have high sensitivity to oxygen and moisture and higher resistance. It was extremely insufficient as a sealing member for. In addition, in order to apply to a display element provided with a flexible substrate, the flexibility is insufficient and the bending resistance has a problem.

  In addition, a sealing structure that includes a sealing layer, a moisture-proof layer, and a non-flat structure and is provided on the outer peripheral portion of the liquid crystal portion of the display element is disclosed (for example, see Patent Document 3). However, the formation of the non-flat structure of the sealing structure is complicated, the productivity is inferior, and the flexibility is insufficient for application to a display element equipped with a flexible substrate, and there is a problem in bending resistance. It was.

  Therefore, development of a side sealing method that can perform sealing with excellent moisture resistance by a simple method, is suitable for a display element provided with a flexible substrate, has excellent flexibility, and can realize a narrow bezel. Longed for.

JP 2014-022158 A JP 2009-080396 A JP 2014-119705 A

  The present invention has been made in view of the above problems, and its solution is a side sealing technique of an organic electroluminescence element composed of a flexible member, even in a high temperature and high humidity environment even with a narrow bezel width. It is providing the organic electroluminescent device excellent in durability and bending resistance, and its manufacturing method.

  As a result of intensive studies in view of the above problems, the present inventor has a laminate in which at least an organic electroluminescence element unit and a flexible sealing plate are laminated in this order on a flexible substrate, and at least the organic electroluminescence An organic electroluminescent device, characterized in that a side surface portion of a laminate composed of a luminescent element unit and the flexible sealing plate is formed of a water-repellent polymer whose surface energy is not more than a specific condition as a main component. Thus, it was found that an organic electroluminescence device excellent in durability and bending resistance under a high temperature and high humidity environment can be obtained even with a narrow bezel width, and the present invention has been achieved.

  That is, the said subject of this invention is solved by the following means.

1. An organic electroluminescence device having a laminate in which at least an organic electroluminescence element unit and a flexible sealing plate are laminated in this order on a flexible substrate,
Having a side surface sealing layer on a side surface part of a laminate composed of at least the organic electroluminescence element unit and the flexible sealing plate;
The organic electroluminescent device, wherein the side surface sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less as a main component.

2. 2. The organic electroluminescence device according to claim 1, wherein the polymer contained in the side sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less.

  3. 3. The organic electroluminescence device according to claim 1, wherein at least a part of the side surface sealing layer is bonded and fixed to the flexible substrate.

  4). A gas barrier layer is provided between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. The organic electroluminescent device according to any one of items 1 to 3.

  5. 5. The organic electroluminescence device according to item 4, wherein the gas barrier layer is a polysilazane modified layer.

6). After producing a laminate by laminating at least an organic electroluminescence element unit and a flexible sealing plate in this order on a flexible substrate,
A side sealing layer forming material whose main component is a polymer having a surface energy of 30 × 10 ⁻³ N / m or less on a side surface portion composed of at least the organic electroluminescence element unit and the flexible sealing plate of the laminate. A method for producing an organic electroluminescent device, comprising forming a side sealing layer using

7). 7. The method for producing an organic electroluminescent device according to item 6, wherein the polymer used for forming the side sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less.

  8). 8. The method for manufacturing an organic electroluminescent device according to claim 6, wherein at least a part of the side surface sealing layer is bonded and fixed to the flexible substrate.

  9. A gas barrier layer is formed between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. The manufacturing method of the organic electroluminescent device as described in any one of Claim 8.

  10. The method for producing an organic electroluminescent device according to item 9, wherein the gas barrier layer is formed by applying a modification treatment by irradiation with vacuum ultraviolet light using a coating liquid containing polysilazane.

  By the above means of the present invention, it is possible to provide an organic electroluminescent device excellent in durability and bending resistance under a high temperature and high humidity environment even with a narrow bezel width, and a method for producing the same.

  It is presumed that the above problem can be solved by the configuration defined in the present invention for the following reason.

  As described above, as a method for manufacturing an organic electroluminescence device, in consideration of productivity, after producing a long organic electroluminescence by a roll-to-roll method, a desired size is obtained according to the purpose of use. It is cut into a single wafer form. When cutting into such a single wafer form, the edge is subjected to normal stress, microcracks and delamination occur at the edge of organic electroluminescence, and moisture and oxygen can easily enter from the generated crack and peel. Become. In order to suppress this, it is necessary to suppress the adsorption, dissolution, diffusion, and the like of moisture on the end surface after cutting.

  As a conventional method, there is a method of forming a side sealing layer containing a polymer and inorganic particles or a vapor deposition gas barrier layer at the end, but it is difficult due to the shape factor of the end, or when stress is concentrated on the end In such a sealing member, the effectiveness as a means could not be found because it was poor in flexibility and easily broken.

In view of the above problems, the present inventors have found that in order to prevent moisture intrusion at the edge, a method for suppressing moisture adsorption and dissolution at the edge and accompanying diffusion into the layer is effective. It was. As a result of further detailed investigation on the surface characteristics for achieving the above characteristics, by forming the side surface sealing layer with a polymer having a surface energy of 30 × 10 ⁻³ N / m or less, In the side sealing layer surface, it exhibits a high level of water repellency and antifouling properties, and can prevent moisture from adsorbing, dissolving and diffusing into the film on the side surface. It has been found that excellent moisture resistance can be exhibited when stored. Furthermore, since the end portion is a non-light emitting region (bezel portion), a sufficient diffusion distance can be obtained by making the side surface sealing layer into a thick film design, providing flexibility and moisture adsorption and dissolution. It was possible to suppress efficiently and arrived at the present invention.

Schematic sectional view showing an example of the configuration of the organic electroluminescence device of the comparative example Schematic sectional drawing which shows an example of a structure of the organic electroluminescent device which comprised the side surface sealing layer which concerns on this invention Schematic sectional drawing which shows another example of a structure of the organic electroluminescent device which comprised the side surface sealing layer which concerns on this invention Schematic which showed an example of the manufacturing method which forms the side surface sealing layer which concerns on this invention in the side part of a laminated body Schematic which showed another example of the manufacturing method which forms the side surface sealing layer which concerns on this invention in the side part of a laminated body

The organic electroluminescence device of the present invention has a laminate in which at least an organic electroluminescence element unit and a flexible sealing plate are laminated in this order on a flexible substrate, and at least the organic electroluminescence element unit and the flexible seal are stacked. It has a side sealing layer on the side part of the laminate composed of a stop plate, and the side sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less as a main component. It is possible to realize an organic electroluminescence device that is excellent in durability and bending resistance in a high-temperature and high-humidity environment even with a narrow bezel width. This feature is a technical feature common to the inventions according to claims 1 to 10.

As an embodiment of the present invention, the polymer contained in the side surface sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less from the viewpoint that the effects of the present invention can be further expressed. Therefore, it is possible to effectively prevent moisture from entering from the side surface due to the development of an excellent water repellent effect, and it is possible to obtain superior durability under a high temperature and high humidity environment, which is preferable.

  In addition, it is preferable that at least a part of the side surface sealing layer is bonded and fixed to the flexible substrate from the viewpoint of exhibiting a more excellent sealing effect.

  In addition, a gas barrier layer is formed between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. Furthermore, this is a preferred embodiment from the viewpoint that oxygen and moisture can be more effectively prevented from entering from the flexible substrate side.

  In addition, it is preferable that the gas barrier layer is a polysilazane modified layer formed by a wet coating method from the viewpoint that a dense gas barrier layer can be formed with a simple apparatus.

Furthermore, in the method for producing an organic electroluminescence device of the present invention, at least an organic electroluminescence element unit and a flexible sealing plate are laminated in this order on a flexible substrate, and then a laminate is produced. Side sealing using a side sealing layer forming material mainly composed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less on a side surface composed of an organic electroluminescence element unit and the flexible sealing plate A layer is formed.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, "-" shown in this invention is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

<< Basic configuration of organic EL element device >>
A basic configuration of the organic EL device of the present invention will be described with reference to the drawings. In addition, the number described in parentheses after each component represents the code of the component described in each figure.

  FIG. 1 is a schematic cross-sectional view showing an example of the configuration of a conventional organic EL device which is a comparative example.

  In the organic EL device (1) which is a comparative example described in FIG. 1, an organic EL element unit (3) composed of an anode, an organic functional layer group including a light emitting layer, a cathode and the like on a flexible substrate (2) and Sealing adhesive for adhering the laminate (M) composed of the flexible sealing plate (4) to the organic EL element unit (3) and the flexible sealing plate (4) (6).

  In the organic EL device (1) configured as shown in FIG. 1, the function for preventing the influence from the outside on the end of the organic EL element unit (3) is mainly used as a sealing adhesive ( 6), but since this sealing adhesive (6) does not have a sufficient sealing function, the width at the end of the organic EL element unit (3) from the outside (bezel width (L )) Need to be designed thick. As a result, there is a problem that the light emitting area of the organic EL element is reduced.

Based on the above problems, the organic EL element device of the present invention has a laminate in which an organic EL element unit and a flexible sealing plate are laminated in this order on a flexible substrate, and at least the organic EL element unit and the flexible sealing. It has a side sealing layer on the side part of the laminate composed of plates, and the side sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less as a main component. Features.

  FIG.2 and FIG.3 is a schematic sectional drawing which shows an example of a structure of the organic electroluminescent device which comprised the side surface sealing layer based on this invention.

(A) of FIG. 2 is the 1st embodiment of this invention, and is comprised with the organic EL element unit (3) and the flexible substrate (4) with respect to the organic EL device (1) shown in FIG. A side sealing layer (5) formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less is provided on the outer peripheral portion of the laminate (M), and an end portion of the organic EL element unit (3). Or, the effect of effectively preventing moisture and the like from entering from the side surface of the laminate is exhibited.

The polymer constituting the side sealing layer (5) according to the present invention has a characteristic that the surface energy is 30 × 10 ⁻³ N / m or less, and the water repellency and prevention at the surface portion of the side sealing layer (5). It has excellent soiling properties, can prevent moisture from adsorbing, dissolving and diffusing into the membrane on the side, and exhibits excellent moisture resistance when stored in a high humidity and high temperature environment. . Moreover, since it has such an excellent moisture-proof effect, the bezel width (L) can be designed narrowly as shown in FIG. In the present invention, the bezel width (L) is preferably 2.0 mm or less, more preferably within the range of 0.1 to 1.0 mm, still more preferably 0.1 to 0.5 mm. Is within the range.

In the present invention, the polymer contained in the side sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less, or as shown in FIG. It is a preferable aspect that at least a part of the side surface sealing layer (5), for example, the lower end portion is bonded and fixed to the flexible substrate (2).

  This is because the substrate and the sealing plate constituting the organic EL device of the present invention are both formed of a flexible material, and a fluorine-containing polymer having excellent moisture resistance and flexibility is disposed on the side surface layer on the side surface sealing layer. By doing so, even when subjected to stress such as bending, this is a preferred embodiment from the viewpoint that stress relaxation can be performed smoothly without causing film surface breakage.

  As shown in FIG. 2 (b), the second preferred embodiment as the organic EL device of the present invention is provided with a gas barrier layer (7) between the flexible substrate (2) and the organic EL element unit (3). It is the structure to provide. By setting it as such a structure, the penetration | invasion from the flexible substrate surface side of the water | moisture content and harmful gas which influences organic EL can be prevented.

  Furthermore, if necessary, as shown in FIG. 2C, in addition to the configuration of FIG. 2B, the second gas barrier layer (7B) is formed on the lower surface side of the flexible sealing plate (4). ) May be provided. In particular, in the case of a method of taking out light emission of the organic EL element from both sides, when using a resin substrate instead of a metal thin film as the flexible sealing plate (4), from the viewpoint of improving moisture resistance and the like. The second gas barrier layer (7B) is preferably provided.

  The gas barrier layer can be formed by a general vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or a vacuum ultraviolet ray using polysilazane. Although there is a method of performing the treatment, in the present invention, the latter method which does not require a large vacuum facility or the like is preferable.

  Moreover, as a 3rd embodiment of the organic EL device of this invention, as shown to (a)-(c) of FIG. 3, a side surface sealing layer (5) is provided in the whole side surface part of an organic EL device. A configuration is also preferable.

  Further, as a fourth embodiment of the organic EL device of the present invention, as shown in FIG. 3 (d), a flexible substrate (2), a gas barrier layer (7), an organic EL element unit (7), a sealing A method of forming the side sealing layer (5) in the entire side region after the fixing adhesive layer (3) and the flexible sealing plate (4) are configured with the same area, and the cross section is cut to a predetermined size. Can also be preferably used. In the case of such a configuration, the thickness of the side sealing layer (5) is the bezel width (L).

<< Each component of organic EL device >>
Next, details of each component of the organic EL device of the present invention will be described.

(Side sealing layer)
In the organic EL device of the present invention, it is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less as a main component on at least a side surface of a laminate composed of an organic electroluminescence element unit and a flexible sealing plate. It is characterized by having a side sealing layer.

The “main component” in the present invention means that the ratio of the polymer having a surface energy of 30 × 10 ⁻³ N / m or less to the total mass of the side sealing layer is 70% by mass or more, preferably It is 80 mass% or more, More preferably, it is 90 mass% or more, Especially preferably, it is the structure of only a polymer (100 mass%) whose surface energy is 30 * 10 < ^-3 > N / m or less.

(Measurement method of surface energy)
For the measurement of the surface energy in the present invention, a method for measuring the surface energy with a wetting reagent based on JIS-K6768: 1999 can be applied. Specifically, it can be determined by measurement according to the method described below.

  A polymer thin film to be measured is applied and dried on a flat glass substrate in advance under a condition that the thickness after drying is 50 μm, and is conditioned for 1 day in an environment of 25 ° C. and 55% RH. A measurement plate is prepared.

  Next, using a FACE contact angle meter CA-D type (manufactured by Kyowa Interface Science Co., Ltd.), in an environment of 25 ° C. and 55% RH, ethylene glycol, n-hexadecane, and methylene iodide were respectively placed on the measurement plate. 3 μl of the droplet amount is dropped and each contact angle is measured, and the surface energy (mN / m) is calculated from the value and Young-Fowkes equation.

(Polymer material)
In general, fluorine-based surfactants or silicon compounds have been used as water- and oil-repellent materials and antifouling materials. However, in the present invention, the surface energy is 30 × 10 ⁻³ N / m as a main component. It is characterized by adapting the following polymers:

  The polymer referred to in the present invention is a material having a weight average molecular weight of 20,000 or more, preferably in the range of 10,000 to 5,000,000, more preferably in the range of 20,000 to 2,000,000, Preferably it is in the range of 50,000 to 800,000.

The polymer applicable to the formation of the side sealing layer according to the present invention is not particularly limited as long as the surface energy is 30 × 10 ⁻³ N / m or less, and is selected from a hydrophobic polymer or a water-repellent polymer. For example, a polypropylene polymer, a polyethylene polymer, a polyvinyl polymer, a polyvinylidene polymer, a fluorine polymer, a silicon polymer, and the like can be mentioned. In the present invention, among these, the surface energy is 20 ×. A fluorine-based polymer of 10 ⁻³ N / m or less is preferable.

  Examples of the fluorine polymer applicable in the present invention include polytetrafluoroethylene, tetrafluoroethylene / perfluoroalkyl vinyl ether polymer, tetrafluoroethylene / hexafluoropropylene copolymer, tetrafluoroethylene / ethylene copolymer, Copolymers of tetrafluoroethylene and heterocycle-containing fluorine monomers, polychlorotrifluoroethylene, fluoroalkyl (meth) acrylate polymers, fluoroalkyl (meth) acrylates and other alkyl (meth) acrylate copolymers, vinylidene fluoride , Vinylidene fluoride and tetrafluoroethylene copolymer, vinylidene fluoride and perfluoroalkyl vinyl ether copolymer, and the like.

Moreover, a commercial item can be used for the fluorine-type polymer of 20 * 10 < ^-3 > N / m or less, for example, Fluoro Surf (trademark) FG-30303 series etc. by a Fluoro Technology company etc. can be mentioned.

  In the present invention, other polymers and the like can be used in combination with the fluoropolymer within the range having the surface energy condition defined in the present invention.

(Method for forming side sealing layer)
As a method for forming a side surface sealing layer according to the present invention, a polymer having a surface energy of 30 × 10 ⁻³ N / m or less, more preferably a fluorine-based polymer having a surface energy of 20 × 10 ⁻³ N / m or less. Then, after dissolving in a polymer-soluble solvent at a predetermined concentration to prepare a side surface sealing layer forming coating liquid (9), for example, an organic EL device (1) cut to a predetermined size as shown in FIG. For example, the four sides of the side surface of the laminate (M) are used as a wet coater (8), and an inkjet discharge type head is used to apply the side surface sealing layer forming coating liquid (9) to a predetermined region A → The side sealing layer (5) of Embodiment 1 illustrated in FIG. 2A or the side sealing of Embodiment 2 illustrated in FIG. 2B is discharged and dried in the order of B → C → D. A stop layer (5) can be formed.

  Moreover, as a formation method of Embodiment 3, as shown in FIG. 5, the said side surface sealing layer formation coating liquid (9) is applied with respect to the whole side part of the organic EL device (1) cut to predetermined size. Using the wet coater (8), the side seals of Embodiment 3 and Embodiment 4 illustrated in FIGS. 3A to 3D are applied and dried in the order of A → B → C → D. A method of forming the stop layer (5) can also be applied.

In the preparation of the side sealing layer forming coating solution (9), the content of the polymer having a surface energy of 30 × 10 ⁻³ N / m or less according to the present invention is 10 to 70 with respect to the total mass of the coating solution. It is preferably in the range of mass%, more preferably in the range of 10-50 mass%. When the content of the polymer is 10% by mass or more, a side seal layer having a high film thickness can be formed efficiently. Moreover, if content of the said polymer is 70 mass% or less, a coating liquid will not become high viscosity too much and a uniform side sealing layer can be formed stably.

  The solvent applicable to the preparation of the side sealing layer forming coating solution (9) is not particularly limited as long as it is a solvent capable of dissolving the polymer, but is a nonflammable fluorine-based solvent. For example, hydrofluoroether, perfluoropolyether, perfluoroalkane, hydrofluoropolyether, hydrofluorocarbon and the like can be mentioned. In addition, other solvents can be used in combination, for example, flammable fluorine solvents such as trifluoropropanol and metaxylene hexafluoride, and organic solvents such as alcohol, paraffin solvents and ester solvents are mixed. Can do.

  The ratio of the solvent in the side sealing layer forming coating solution (9) is preferably 20 to 90% by mass with respect to the total mass of the coating solution.

  The wet coater (8) used for forming the side surface sealing layer according to the present invention can be used without limitation as long as it is a coater capable of wet coating, for example, a spin coat method, a roll coat method, a flow coat method. , Inkjet method, spray coating method, printing method, dip coating method, bar coating method, gravure printing method, screen printing method, reverse coating method, die coating method and the like.

The thickness of the side sealing layer according to the present invention is not particularly limited as long as it is within a range in which a desired effect can be exhibited, but is preferably within a range of 5 to 300 μm, and within a range of 10 to 200 μm. More preferably, it is particularly preferably within the range of 15-100 μm.
If the thickness of the side sealing layer is 5 μm or more, a sufficient sealing effect against moisture and the like can be exerted, expansion of the bezel width by the side sealing layer is suppressed, and a sufficient light emitting area is secured. Can do. Moreover, if it is 300 micrometers or less, the film | membrane surface destruction (generation | occurrence | production of a crack etc.) at the time of receiving a stress can be prevented, and it is preferable to set to said layer thickness range.

[Flexible substrate]
The flexible substrate as used in the present invention refers to a substrate that is wound around a φ (diameter) 50 mm roll and does not crack before and after winding with a constant tension, and more preferably a substrate that can be wound around a φ30 mm roll.

  The flexible substrate according to the present invention may be light transmissive or light opaque. The flexible substrate applicable to the present invention is not particularly limited, and examples thereof include a resin substrate, a thin film metal foil, and a thin plate flexible glass.

  Examples of the resin substrate applicable to the present invention include polyesters such as polyethylene terephthalate (abbreviation: PET), polyethylene naphthalate (abbreviation: PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, and cellulose triacetate (abbreviation: TAC). Cellulose acetate butyrate, cellulose acetate propionate (abbreviation: CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate and their derivatives, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, Polycarbonate (abbreviation: PC), norbornene resin, polymethylpentene, polyetherketone, polyimide, polyethersulfone ( Name: PES), polyphenylene sulfide, polysulfones, polyether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic and polyarylates, Arton (trade name, manufactured by JSR) and Appel (product) And X, such as cycloolefin resin such as Mitsui Chemical Co., Ltd.).

  Among these resin substrates, films such as polyethylene terephthalate (abbreviation: PET), polybutylene terephthalate, polyethylene naphthalate (abbreviation: PEN), polycarbonate (abbreviation: PC) are flexible in terms of cost and availability. It is preferably used as a resin substrate.

  The resin substrate may be an unstretched film or a stretched film.

  The resin substrate applicable to the present invention can be manufactured by a conventionally known general film forming method. For example, an unstretched resin substrate that is substantially amorphous and not oriented can be produced by melting a resin as a material with an extruder, extruding it with an annular die or a T-die, and quenching. In addition, the resin substrate transport direction (vertical axis direction, MD) is applied to the unstretched resin substrate by a known method such as uniaxial stretching, tenter sequential biaxial stretching, tenter simultaneous biaxial stretching, tubular simultaneous biaxial stretching, or the like. Direction) or a direction (horizontal axis direction, TD direction) perpendicular to the transport direction of the resin substrate, the stretched resin substrate can be produced. Although the draw ratio in this case can be suitably selected according to the resin used as the raw material of the resin substrate, it is preferably in the range of 2 to 10 times in the vertical axis direction and the horizontal axis direction.

  The thickness of the resin substrate is preferably a thin resin substrate within the range of 3 to 200 μm, more preferably within the range of 10 to 150 μm, and particularly preferably within the range of 20 to 120 μm. is there.

  Moreover, the thin plate flexible glass applicable as the flexible substrate according to the present invention is a glass plate that is thin enough to be bent. The thickness of the thin flexible glass can be appropriately set within the range in which the thin flexible glass exhibits flexibility.

  Examples of the thin flexible glass include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. As thickness of thin plate flexible glass, it is the range of 5-300 micrometers, for example, Preferably it is the range of 20-150 micrometers.

  The material for forming the thin film metal foil is, for example, one or more metals selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum. The thing which consists of alloys is mentioned. The thickness of the thin film metal foil can be appropriately set within a range in which the thin film metal foil exhibits flexibility, and is, for example, in the range of 10 to 100 μm, and preferably in the range of 20 to 60 μm.

[Gas barrier layer]
In the present invention, the gas barrier layer is provided between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer according to the present invention is bonded and fixed to the gas barrier layer. Is preferred.

  In the present invention, the first method for forming the gas barrier layer includes a vapor deposition method, and more specifically, a physical vapor deposition method (PVD method) or a chemical vapor deposition method (CVD method). Is mentioned.

  The physical vapor deposition method (PVD method) is a method of depositing a target material, for example, a thin film such as a carbon film, on the surface of the material in a gas phase by a physical method. Examples thereof include a DC sputtering method, an RF sputtering method, an ion beam sputtering method, and a magnetron sputtering method, a vacuum deposition method, and an ion plating method.

  The chemical vapor deposition (CVD) method is a method of depositing a film by a chemical reaction on the surface of the substrate or in the vapor phase by supplying a raw material gas containing a target thin film component onto the substrate. It is. In addition, for the purpose of activating the chemical reaction, there is a method of generating plasma or the like. Known CVD such as thermal CVD method, catalytic chemical vapor deposition method, photo CVD method, vacuum plasma CVD method, atmospheric pressure plasma CVD method, etc. The method etc. are mentioned. Although not particularly limited, it is preferable to apply a plasma CVD method such as a vacuum plasma CVD method or an atmospheric pressure plasma CVD method from the viewpoint of film forming speed and processing area.

  For example, if a silicon compound is used as a raw material compound and oxygen is used as the decomposition gas, silicon oxide is generated. This is because highly active charged particles and active radicals exist in the plasma space at a high density, so that multistage chemical reactions are accelerated at high speed in the plasma space, and the elements present in the plasma space are thermodynamic. This is because it is converted into an extremely stable compound in a very short time.

Examples of the chemical vapor deposition method (CVD method) applicable in the present invention include, for example, JP 2006-321127 A, JP 2007-59244 A, JP 2012-131194 A, 2013-28170, The methods described in JP 2014-141707 A, JP 2014-189891 A, and the like can be referred to, and a conventionally known sputtering method can also be applied as a sputtering method. And a method of forming SiO ₂ as a target using an L-430S-FHS sputtering apparatus manufactured by Anerva.

  As a second method of forming a gas barrier layer, a gas barrier layer-forming coating solution containing polysilazane is applied to form a coating film, and then subjected to a modification treatment by irradiating with vacuum ultraviolet rays to effect a polysilazane modified layer. And the like (hereinafter referred to as a polysilazane modification method). In the present invention, a polysilazane modification method that does not require a large vacuum facility is particularly preferred.

(Formation method of gas barrier layer by polysilazane modification method)
Next, in the present invention, the details of the polysilazane modification method, which is a preferred method for forming the gas barrier layer, will be described.

  The gas barrier layer according to the present invention forms a polysilazane-modified layer by forming a polysilazane-containing layer as a gas barrier precursor layer and then performing a modification treatment using vacuum ultraviolet rays or the like.

  In the polysilazane-containing layer according to the present invention, the polysilazane-containing layer is not formed in the state where all of the ceramic precursor inorganic polymer that is the polysilazane is formed as it is, and the polysilazane-containing layer is formed. The polysilazane is modified into silica or the like by a heat treatment in a drying process or the like, or a modification treatment such as forced annealing, ultraviolet irradiation, or vacuum ultraviolet irradiation. At this time, it is not necessary to modify all of the polysilazane, and it is sufficient that at least a part of the polysilazane is modified.

<Constitutional materials of polysilazane>
“Polysilazane” according to the present invention is a polymer having a silicon-nitrogen bond, and is composed of Si—N, Si—H, N—H, etc., SiO ₂ , Si ₃ N ₄ and both intermediate solid solutions SiO _x N _y, etc. The ceramic precursor inorganic polymer.

  The polysilazane is preferably a compound that is converted to silica by being ceramicized at a relatively low temperature so as to be applied so as not to impair the shape and planarity of the thin resin substrate. For example, the polysilazane is described in JP-A-8-112879. A compound having a main skeleton composed of units represented by the following general formula (I) is preferred.

In the general formula (I), R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkylsilyl group, an alkylamino group, an alkoxy group, or the like. Represent.

In the present invention, from the viewpoint of the denseness of the resulting polysilazane-containing layer, perhydropolysilazane (abbreviation: PHPS) in which all of R ₁ , R ₂ and R ₃ are hydrogen atoms is particularly preferable.

  In addition, the organopolysilazane in which a part of the hydrogen atom bonded to Si is substituted with an alkyl group or the like has an alkyl group such as a methyl group, so that the adhesive property between the flexible substrate as a base and the polysilazane-containing layer is reduced. The ceramic film made of polysilazane, which is hard and brittle, can be toughened, and even when the film thickness (average film thickness) is increased, the occurrence of cracks can be suppressed. Accordingly, perhydropolysilazane and organopolysilazane may be appropriately selected according to the application, and may be used in combination.

  Perhydropolysilazane is presumed to have a linear structure and a ring structure centered on 6- and 8-membered rings. Its molecular weight is about 600 to 2000 (polystyrene conversion) in terms of number average molecular weight (Mn), and there is a liquid or solid substance, and its state varies depending on the molecular weight. These are marketed in a solution state dissolved in an organic solvent, and the commercially available product can be used as it is as a polysilazane-containing coating solution.

  As another example of the polysilazane compound that is ceramicized at a low temperature, a silicon alkoxide-added polysilazane obtained by reacting a silicon alkoxide with a polysilazane having a main skeleton composed of a unit represented by the general formula (I) (for example, a special No. 5-238827), a glycidol-added polysilazane obtained by reacting glycidol (for example, see JP-A-6-122852), and an alcohol-added polysilazane obtained by reacting an alcohol (eg, JP-A-6-6). -240208), a metal carboxylate-added polysilazane obtained by reacting a metal carboxylate (see, for example, JP-A-6-299118), and a metal-containing acetylacetonate complex. Acetylacetonate complex-added polysilaza (E.g., JP-A-6-306329 JP reference.), Fine metal particles of the metal particles added polysilazane obtained by adding (e.g., JP-A-7-196986 JP reference.), And the like.

  As an organic solvent for preparing a coating liquid for forming a polysilazane-containing layer containing polysilazane, it is preferable to avoid the use of an alcohol-based organic solvent that easily reacts with polysilazane or an organic solvent containing moisture. Therefore, specifically, hydrocarbon solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons, halogenated hydrocarbon solvents, and ethers such as aliphatic ethers and alicyclic ethers can be used. . Specifically, there are hydrocarbons such as pentane, hexane, cyclohexane, toluene, xylene, solvesso and turben, halogen hydrocarbons such as methylene chloride and trichloroethane, ethers such as dibutyl ether, dioxane and tetrahydrofuran. These organic solvents may be selected according to characteristics such as the solubility of polysilazane and the evaporation rate of the organic solvent, and a plurality of organic solvents may be mixed.

  The polysilazane concentration in the coating liquid for forming a polysilazane-containing layer containing polysilazane varies depending on the film thickness of the target polysilazane-containing layer and the pot life of the coating liquid, but is in the range of 0.2 to 35% by mass. Is preferred.

  An amine or metal catalyst can be added to the polysilazane-containing coating solution for forming a polysilazane-containing layer in order to promote the modification to the silicon oxide compound. Specific examples include Aquamica NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL150A, NP110, NP140, and SP140 manufactured by AZ Electronic Materials.

<Formation of polysilazane-containing layer>
The polysilazane-containing layer is preferably formed by a wet process using the polysilazane-containing layer forming coating liquid having the above-described configuration. For example, spin coating method, casting method, die coating method, blade coating method, roll coating method, ink jet method, printing method, spray coating method, curtain coating method, LB method (Langmuir Brodgett method), etc. be able to.

  In the present invention, the thickness of the polysilazane-containing layer can be appropriately set according to the purpose. For example, the thickness after drying is preferably in the range of 1 nm to 100 μm, more preferably in the range of 10 nm to 10 μm, and most preferably in the range of 10 nm to 1 μm.

<Modification treatment of polysilazane-containing layer>
In the present invention, the polysilazane-containing layer is modified to form a polysilazane modified layer.

  The modification treatment is performed on the polysilazane constituting the polysilazane-containing layer, whereby a part or all of the polysilazane contained in the polysilazane-containing layer is modified into a polysilazane modified body.

  As a specific modification treatment, a known method based on the conversion reaction of polysilazane can be selected. Modification to a silicon oxide film or a silicon oxynitride film by a substitution reaction of silazane requires a heat treatment at 450 ° C. or higher, and is difficult to apply to a thin resin substrate applied to the present invention. In order to apply to the thin film resin substrate according to the present invention, a method such as plasma treatment, ozone treatment, ultraviolet irradiation treatment, vacuum ultraviolet irradiation treatment or the like capable of proceeding the conversion reaction at a low temperature can be used.

  In addition, when performing a modification process with respect to a polysilazane content layer, it is preferable that the water | moisture content is removed as mentioned above before the said modification process.

  As the modification treatment applicable to the present invention, the above ultraviolet irradiation, vacuum ultraviolet irradiation, and plasma irradiation are desirable, and vacuum ultraviolet irradiation is particularly preferable from the viewpoint of the modification effect of polysilazane.

  Hereinafter, an ultraviolet irradiation process and a vacuum ultraviolet irradiation process will be described as typical modification methods.

<Ultraviolet irradiation treatment>
Hereinafter, an ultraviolet irradiation process which is one method of the modification process will be described.

  Ozone and active oxygen atoms generated by ultraviolet rays (synonymous with ultraviolet light) have high oxidation ability, and can form silicon oxide or silicon oxynitride having high density and insulation properties at low temperatures. .

  In the present invention, any commonly used ultraviolet ray generator can be used.

  The “ultraviolet rays” referred to in the present invention generally refers to electromagnetic waves having a wavelength in the region of 10 to 400 nm, but the wavelength range to be applied to vacuum ultraviolet rays (within a wavelength range of 10 to 200 nm) described later is used. In order to classify, in the case of the ultraviolet irradiation treatment, ultraviolet rays having a wavelength within the range of 210 to 350 nm are preferably used.

  The irradiation conditions of the ultraviolet rays are set such that the irradiation intensity and the irradiation time are set within a range in which the thin resin substrate carrying the irradiated polysilazane-containing layer is not damaged.

  Examples of such ultraviolet light generation light sources include metal halide lamps, high-pressure mercury lamps, low-pressure mercury lamps, xenon arc lamps, carbon arc lamps, and excimer lamps (single wavelengths of 222 nm and 308 nm, for example, manufactured by USHIO INC.) ), A UV light laser and the like, and are not particularly limited. In addition, when irradiating the coating layer with the generated ultraviolet rays, it is desirable to apply the ultraviolet rays from the generation source to the coating layer after reflecting the ultraviolet rays from the generation source with a reflector in order to achieve uniform irradiation and improve efficiency. .

  The ultraviolet irradiation can be adapted to both batch processing and continuous processing, and can be appropriately selected depending on the shape of the flexible substrate.

<Vacuum UV irradiation treatment; Excimer irradiation treatment>
In the present invention, a more preferable modification treatment method is a treatment method by vacuum ultraviolet irradiation.

  In the treatment method by vacuum ultraviolet irradiation, light energy of 100 to 200 nm, preferably light energy having a wavelength of 100 to 180 nm, which is larger than the interatomic bonding force constituting the polysilazane compound, is used, and only photons called photon processes are used to bond atoms. In this method, a silicon oxide film or the like is formed in a relatively low temperature environment by causing an oxidation reaction with active oxygen or ozone to proceed while cutting directly.

  As a vacuum ultraviolet light source required for this, a rare gas excimer lamp is preferably used.

  In addition, although there is no restriction | limiting in particular as a detailed content and specific conditions of a vacuum ultraviolet irradiation process (excimer irradiation process), For example, paragraph number [0079]-same [0091] of Unexamined-Japanese-Patent No. 2011-031610 The contents described therein or the contents described in paragraph numbers [0086] to [0098] of JP 2012-016854 A can be referred to.

[Organic EL element unit]
Next, details of the organic EL element unit (3) formed on the flexible substrate (2) produced above or on the flexible substrate (2) / gas barrier layer (7) will be described.

  As the configuration of the organic EL element unit (3) according to the present invention, various layer configurations can be applied on the flexible substrate (2) or the flexible substrate (2) / gas barrier layer (7). And may have a layered structure described in (i) to (v) below. Further, the following light emitting layer is preferably composed of a blue light emitting layer, a green light emitting layer and a red light emitting layer.

(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) Anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode Next, each component of the organic EL element unit will be described.

(Anode: 1st electrode)
When the first electrode is provided on one surface side of the flexible substrate, the first electrode is a transparent electrode that functions as an anode.

As a material constituting the first electrode (transparent electrode), a metal such as Ag, Au or the like, an alloy containing a metal as a main component, a CuI or indium-tin composite oxide (ITO), a metal such as SnO ₂ and ZnO An oxide can be mentioned, but from the viewpoint of controlling the objective effect of the present invention, in particular, the difference in refractive index from the charge injection layer to a desired condition, it is a metal or an alloy containing a metal as a main component. It is preferable that there is, and more preferable is silver or an alloy containing silver as a main component.

  The purity of silver constituting the transparent electrode as the first electrode is preferably 99% or more. Further, palladium (Pd), copper (Cu), gold (Au), or the like may be added to ensure the stability of silver.

  Moreover, when a transparent electrode is comprised from the alloy which has silver as a main component, it is preferable that the content rate of silver is 50% or more. Examples of such alloys include silver magnesium (AgMg), silver-copper (Ag-Cu), silver-palladium (Ag-Pd), silver-palladium-copper (Ag-Pd-Cu), silver-indium (Ag). -In), silver-gold (Ag-Au), silver-aluminum (Ag-Al), silver-zinc (Ag-Zn), silver-tin (Ag-Sn), silver-platinum (Ag-Pt), silver -Titanium (Ag-Ti), silver-bismuth (Ag-Bi), etc. are mentioned.

  As a method for forming such a transparent electrode, a method using a wet process such as a coating method, an inkjet method, a coating method, a dip method, a vapor deposition method (resistance heating, EB method, etc.), a sputtering method, a CVD method, etc. Examples include a method using a dry process. Of these, the vapor deposition method is preferably applied. Moreover, you may form into a film the layer containing a nitrogen atom as a base layer between a transparent electrode and a transparent base material. In addition, the transparent electrode composed of silver or an alloy containing silver as a main component is characterized by having sufficient conductivity even without an annealing treatment or the like. Etc. may be performed.

(Intermediate electrode)
The organic EL element unit has a structure in which two or more organic functional layer groups are stacked between the first electrode and the second electrode, and electrical connection is obtained between the two or more organic functional layer units. Therefore, the structure can be separated by an intermediate electrode layer unit having an independent connection terminal.

  Subsequently, the structure of the organic functional layer group containing a light emitting layer is demonstrated.

(Charge injection layer)
In the organic EL element unit according to the present invention, the charge injection layer is a layer provided between the electrode and the light emitting layer in order to lower the driving voltage and improve the light emission luminance. The details are described in Chapter 2, “Electrode Materials” (pp. 123-166) of Volume 2 of “November 30, 1998, issued by NTS Corporation”. There is.

  As a charge injection layer, generally, if it is a hole injection layer, it exists between a transparent anode and a light emitting layer or a hole transport layer, and if it is an electron injection layer, it exists between a cathode and a light emitting layer or an electron transport layer. Can be made.

  In the present invention, the hole injection layer is preferably a layer disposed adjacent to the transparent anode according to the present invention in order to lower the driving voltage and improve the light emission luminance. (Published on November 30, 1998 by NTS Corporation) "Volume 2 Chapter 2" Electrode Materials "(pp. 123-166).

  The details of the hole injection layer are also described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069, etc. Examples of the material used for the hole injection layer include: , Porphyrin derivatives, phthalocyanine derivatives, oxazole derivatives, oxadiazole derivatives, triazole derivatives, imidazole derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, hydrazone derivatives, stilbene derivatives, polyarylalkane derivatives, triarylamine derivatives, carbazole derivatives, Inrocarbazole derivatives, isoindole derivatives, acene derivatives such as anthracene and naphthalene, fluorene derivatives, fluorenone derivatives, polyvinylcarbazole, aromatic amines introduced into the main chain or side chain Material or oligomer, polysilane, a conductive polymer or oligomer (e.g., PEDOT (polyethylene dioxythiophene): PSS (polystyrene sulfonic acid), aniline copolymers, polyaniline, polythiophene, etc.) and the like can be mentioned.

  Examples of the triarylamine derivative include benzidine type represented by α-NPD (4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl), and MTDATA (4,4 ′, 4 ″). Examples include a starburst type represented by -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine) and a compound having fluorene or anthracene in the triarylamine-linked core.

  In addition, hexaazatriphenylene derivatives such as those described in JP-A-2003-519432 and JP-A-2006-135145 can also be used as a hole transport material.

  The electron injection layer is a layer provided between the cathode and the light emitting layer for lowering the driving voltage and improving the light emission luminance. When the cathode is composed of the transparent electrode according to the present invention, Chapter 2 “Electrode materials” (pages 123-166) of the second edition of “Organic EL elements and their forefront of industrialization” (published on November 30, 1998 by NTT) ) Is described in detail.

  The details of the electron injection layer are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specific examples of materials preferably used for the electron injection layer are as follows. Metals represented by strontium and aluminum, alkali metal compounds represented by lithium fluoride, sodium fluoride, potassium fluoride, etc., alkali metal halide layers represented by magnesium fluoride, calcium fluoride, etc. Examples thereof include an alkaline earth metal compound layer typified by magnesium, a metal oxide typified by molybdenum oxide and aluminum oxide, and a metal complex typified by lithium 8-hydroxyquinolate (Liq). Moreover, when the transparent electrode in this invention is a cathode, organic materials, such as a metal complex, are used especially suitably. The electron injection layer is desirably a very thin film, and although depending on the constituent material, the layer thickness is preferably in the range of 1 nm to 10 μm.

  In the present invention, the average value Δn of the refractive index difference (absolute value) from the transparent electrode is set in the range of 0.5 to 2.0, so that the metal or metal of the transparent electrode to be applied is a main component. A material for the charge injection layer that satisfies the above conditions is appropriately selected in relation to the refractive index of the alloy.

(Light emitting layer)
In the organic EL element unit according to the present invention, the light emitting layer constituting the organic functional layer group preferably includes a phosphorescent light emitting compound as a light emitting material.

  This light emitting layer is a layer that emits light by recombination of electrons injected from the electrode or the electron transport layer and holes injected from the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. Alternatively, it may be the interface between the light emitting layer and the adjacent layer.

  As such a light emitting layer, there is no restriction | limiting in particular in the structure, if the light emitting material contained satisfy | fills the light emission requirements. Moreover, there may be a plurality of layers having the same emission spectrum and emission maximum wavelength. In this case, it is preferable to have a non-light emitting intermediate layer between the light emitting layers.

  The total thickness of the light emitting layers is preferably in the range of 1 to 100 nm, and more preferably in the range of 1 to 30 nm because a lower driving voltage can be obtained. In addition, the sum total of the thickness of a light emitting layer is the thickness also including the said intermediate | middle layer, when a nonluminous intermediate | middle layer exists between light emitting layers.

  For the light emitting layer as described above, a light emitting material and a host compound to be described later may be used by publicly known methods such as a vacuum deposition method, a spin coating method, a casting method, an LB method (Langmuir-Blodget, Langmuir Broadgett method), and an ink jet method. Can be formed.

  In the light emitting layer, a plurality of light emitting materials may be mixed, and a phosphorescent light emitting material and a fluorescent light emitting material (also referred to as a fluorescent dopant or a fluorescent compound) may be mixed and used in the same light emitting layer. The structure of the light-emitting layer preferably includes a host compound (also referred to as a light-emitting host) and a light-emitting material (also referred to as a light-emitting dopant compound), and emits light from the light-emitting material.

<Host compound>
As the host compound contained in the light emitting layer, a compound having a phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) of less than 0.1 is preferable. Further, the phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the volume ratio in the layer is 50% or more among the compounds contained in a light emitting layer.

  As the host compound, a known host compound may be used alone, or a plurality of types of host compounds may be used. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the efficiency of the organic electroluminescent device can be improved. In addition, by using a plurality of kinds of light emitting materials described later, it is possible to mix different light emission, thereby obtaining an arbitrary light emission color.

  The host compound used in the light emitting layer may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host). )

  Examples of host compounds applicable to the present invention include, for example, JP-A Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002 No. -75645, No. 2002-338579, No. 2002-105445, No. 2002-343568, No. 2002-141173, No. 2002-352957, No. 2002-203683, No. 2002. 363 No. 27, No. 2002-231453, No. 2003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-260861, No. 2002-280183. No. 2002, No. 2002-299060, No. 2002-302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, US Patent Application Publication No. 2003/0175553, US Patent Application Publication No. 2006/0280965, US Patent Application Publication No. 2005/0112407, US Patent Application Publication No. 2009/0017330, US Patent Application Publication No. 2009/0030202, US Patent Public application No. 2005/238919, International Publication No. 2001/039234, International Publication No. 2009/021126, International Publication No. 2008/056746, International Publication No. 2004/093207, International Publication No. 2005/089025, International Publication No. 2007/063796, International Publication No. 2007/063754, International Publication No. 2004/107822, International Publication No. 2005/030900, International Publication No. 2006/114966, International Publication No. 2009/086028, International Publication No. 2009 No./003898, International Publication No. 2012/023947, Japanese Patent Application Laid-Open No. 2008-074939, Japanese Patent Application Laid-Open No. 2007-254297, EP No. 2034538, and the like.

<Light emitting material>
As the light-emitting material that can be used in the present invention, a phosphorescent compound (also referred to as a phosphorescent compound, a phosphorescent material, or a phosphorescent dopant) and a fluorescent compound (both a fluorescent compound or a fluorescent material) are used. Say).

<Phosphorescent compound>
A phosphorescent compound is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. A preferred phosphorescence quantum yield is 0.1 or more, although it is defined as 0.01 or more compounds.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. The phosphorescence quantum yield in the solution can be measured using various solvents, but when using a phosphorescent compound in the present invention, the phosphorescence quantum yield is 0.01 or more in any solvent. Should be achieved.

  The phosphorescent compound can be appropriately selected from known compounds used for the light emitting layer of a general organic EL device, but preferably contains a group 8-10 metal in the periodic table of elements. More preferred are iridium compounds, more preferred are iridium compounds, osmium compounds, platinum compounds (platinum complex compounds) or rare earth complexes, and most preferred are iridium compounds.

  In the present invention, at least one light emitting layer may contain two or more phosphorescent compounds, and the concentration ratio of the phosphorescent compound in the light emitting layer varies in the thickness direction of the light emitting layer. It may be an embodiment.

  Specific examples of known phosphorescent compounds that can be used in the present invention include compounds described in the following documents.

  Nature 395, 151 (1998), Appl. Phys. Lett. 78, 1622 (2001), Adv. Mater. 19, 739 (2007), Chem. Mater. 17, 3532 (2005), Adv. Mater. 17, 1059 (2005), International Publication No. 2009/100991, International Publication No. 2008/101842, International Publication No. 2003/040257, US Patent Application Publication No. 2006/835469, US Patent Application Publication No. 2006 /. Examples thereof include compounds described in US Patent No. 0202194, US Patent Application Publication No. 2007/0087321, US Patent Application Publication No. 2005/0244673, and the like.

Inorg. Chem. 40, 1704 (2001), Chem.
Mater. 16, 2480 (2004), Adv. Mater. 16, 2003 (2004), Angew. Chem. lnt. Ed. 2006, 45, 7800, Appl. Phys. Lett. 86, 153505 (2005), Chem. Lett. 34, 592 (2005), Chem. Commun. 2906 (2005), Inorg. Chem. 42, 1248 (2003), International Publication No. 2009/050290, International Publication No. 2002/015645, International Publication No. 2009/000673, US Patent Application Publication No. 2002/0034656, and US Pat. No. 7,332,232. US Patent Application Publication No. 2009/0108737, US Patent Application Publication No. 2009/0039776, US Patent No. 6921915, US Patent No. 6,687,266, US Patent Application Publication No. 2007/0190359, US Patent Application Publication No. 2006/0008670, US Patent Application Publication No. 2009/0165846, US Patent Application Publication No. 2008/0015355, US Pat. No. 7,250,226, US Pat. No. 7,396,598 , US special Examples include compounds described in Japanese Patent Application Publication No. 2006/0263635, US Patent Application Publication No. 2003/0138657, US Patent Application Publication No. 2003/0152802, US Pat. No. 7090928, and the like. it can.

  Also, Angew. Chem. lnt. Ed. 47, 1 (2008), Chem. Mater. 18, 5119 (2006), Inorg. Chem. 46, 4308 (2007), Organometallics 23, 3745 (2004), Appl. Phys. Lett. 74, 1361 (1999), International Publication No. 2002/002714, International Publication No. 2006/009024, International Publication No. 2006/056418, International Publication No. 2005/019373, International Publication No. 2005/123873, International Publication No. 2005/123873, International Publication No. 2007/004380, International Publication No. 2006/082742, US Patent Application Publication No. 2006/0251923, US Patent Application Publication No. 2005/0260441, US Pat. No. 7,393,599. Description, US Pat. No. 7,534,505, US Pat. No. 7,445,855, US Patent Application Publication No. 2007/0190359, US Patent Application Publication No. 2008/0297033, US Pat. No. 7,338,722 ,USA Examples include compounds described in Japanese Patent Application Publication No. 2002/0134984, US Patent No. 7279704, US Patent Application Publication No. 2006/098120, US Patent Application Publication No. 2006/103874, and the like. Can do.

  Furthermore, International Publication No. 2005/076380, International Publication No. 2010/032663, International Publication No. 2008/140115, International Publication No. 2007/052431, International Publication No. 2011/134013, International Publication No. 2011/157339. International Publication No. 2010/086089, International Publication No. 2009/113646, International Publication No. 2012/020327, International Publication No. 2011/051404, International Publication No. 2011/004639, International Publication No. 2011/073149, Special JP 2012-069737, JP 2009-114086, JP 2003-81988, JP 2002-302671, JP 2002-363552, and the like.

  In the present invention, preferred phosphorescent compounds include organometallic complexes having Ir as a central metal. More preferably, a complex containing at least one coordination mode of a metal-carbon bond, a metal-nitrogen bond, a metal-oxygen bond, or a metal-sulfur bond is preferable.

  The phosphorescent compound described above (also referred to as a phosphorescent metal complex) is described in, for example, Organic Letter, vol. 16, 2579-2581 (2001), Inorganic Chemistry, Vol. 30, No. 8, 1685-1687 (1991), J. Am. Am. Chem. Soc. , 123, 4304 (2001), Inorganic Chemistry, Vol. 40, No. 7, 1704-1711 (2001), Inorganic Chemistry, Vol. 41, No. 12, 3055-3066 (2002) , New Journal of Chemistry. 26, 1171 (2002), European Journal of Organic Chemistry, Vol. 4, pages 695-709 (2004), and the methods described in references in these documents should be applied. Can be synthesized.

<Fluorescent compound>
Fluorescent compounds include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, stilbene dyes. And dyes, polythiophene dyes, and rare earth complex phosphors.

(Hole transport layer)
The hole transport layer is made of a hole transport material having a function of transporting holes. In a broad sense, the hole injection layer and the electron blocking layer also have the function of a hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

  The hole transport material has any of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples include stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, and thiophene oligomers.

  As the hole transport material, those described above can be used, but porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds can be used, and in particular, aromatic tertiary amine compounds can be used. preferable.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl, N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (abbreviation: TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1 -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, '-Di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N, N', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) c Audriphenyl, N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene, 4-N, N- Examples include diphenylamino- (2-diphenylvinyl) benzene, 3-methoxy-4′-N, N-diphenylaminostilbenzene, N-phenylcarbazole and the like.

  For the hole transport layer, known methods such as vacuum deposition, spin coating, casting, printing including ink jet, and LB (Langmuir Brodget, Langmuir Broadgett) are used as the hole transport material. Thus, it can be formed by thinning. Although there is no restriction | limiting in particular about the layer thickness of a positive hole transport layer, Usually, about 5 nm-5 micrometers, Preferably it is the range of 5-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

  Moreover, p property can also be made high by doping the material of a positive hole transport layer with an impurity. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175 and J.P. Appl. Phys. 95, 5773 (2004), and the like.

  Thus, it is preferable to increase the p property of the hole transport layer because an element with lower power consumption can be manufactured.

(Electron transport layer)
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer structure or a stacked structure of a plurality of layers.

  In the electron transport layer having a single-layer structure and the electron transport layer having a multilayer structure, an electron transport material (also serving as a hole blocking material) constituting a layer portion adjacent to the light emitting layer is used as an electron transporting material. What is necessary is just to have the function to transmit. As such a material, any one of conventionally known compounds can be selected and used. Examples include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane, anthrone derivatives, and oxadiazole derivatives. 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 a material for the electron transport layer. it can. Furthermore, a polymer material in which these materials are introduced into a polymer chain, or a polymer material having these materials as a polymer main chain can also be used.

In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (abbreviation: Alq ₃ ), 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 (abbreviation: Znq), etc. and the central metal of these metal complexes A metal complex replaced with In, Mg, Cu, Ca, Sn, Ga, or Pb can also be used as a material for the electron transport layer.

  The electron transport layer can be formed by thinning the above material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an inkjet method, and an LB method. Although there is no restriction | limiting in particular about the layer thickness of an electron carrying layer, Usually, about 5 nm-5 micrometers, Preferably it exists in the range of 5-200 nm. The electron transport layer may have a single structure composed of one or more of the above materials.

(Blocking layer)
The blocking layer includes a hole blocking layer and an electron blocking layer, and is a layer provided as necessary in addition to the constituent layers of the organic functional layer unit 3 described above. For example, it is described in JP-A Nos. 11-204258, 11-204359, and “Organic EL elements and their forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). Hole blocking (hole block) layer and the like.

  The hole blocking layer has a function of an electron transport layer in a broad sense. The hole blocking layer is made of a hole blocking material that has a function of transporting electrons but has a very small ability to transport holes, and recombines electrons and holes by blocking holes while transporting electrons. Probability can be improved. Moreover, the structure of an electron carrying layer can be used as a hole-blocking layer as needed. The hole blocking layer is preferably provided adjacent to the light emitting layer.

  On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense. The electron blocking layer is made of a material that has the ability to transport holes and has a very small ability to transport electrons. By blocking holes while transporting holes, the probability of recombination of electrons and holes is improved. Can be made. Moreover, the structure of a positive hole transport layer can be used as an electron blocking layer as needed. The layer thickness of the hole blocking layer applied to the present invention is preferably in the range of 3 to 100 nm, more preferably in the range of 5 to 30 nm.

(cathode)
The cathode is an electrode film that functions to supply holes to the organic functional layer unit, and a metal, an alloy, an organic or inorganic conductive compound, or a mixture thereof is used. Specifically, gold, aluminum, silver, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, indium, lithium / aluminum mixture, rare earth metal, ITO, ZnO, TiO Oxide semiconductors such as ₂ and SnO ₂ .

  The cathode can be produced by using these conductive materials and forming a thin film by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 5 nm to 5 μm, preferably 5 to 200 nm.

  In the case where the organic EL element is a double-sided light emitting type in which emitted light is extracted also from the cathode side, a cathode with good light transmittance may be selected and configured.

(Sealing member)
The organic EL device of the present invention is characterized in that the cathode and the organic functional layer unit formed between the cathode and the transparent anode are sealed with a flexible sealing plate in order to shield them from the outside air.

  Specifically, as illustrated in FIGS. 2 and 3, as a sealing means applied to the present invention, in addition to the formation of the side surface sealing layer (5), an organic EL element unit ( 3) can be mentioned by forming a sealing structure with a sealing adhesive layer (6) and a flexible sealing plate (4) and bonding them.

  As a flexible sealing board, it should just be arrange | positioned so that the display area | region of an organic EL element unit may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

  Further, in the flexible sealing plate (4) according to the present invention, as shown in FIG. 2 (c) or FIG. 3 (c), on the surface side in contact with the sealing adhesive layer (6), The gas barrier layer may be configured to have two gas barrier layers (7B). The method for forming the gas barrier layer may be the same as the method for forming the gas barrier layer (7, 7A) on the flexible substrate. it can.

  Specifically, as a sealing material used for sealing, a flexible glass plate, a resin substrate, a thin film metal foil, or a metal composite resin film laminated with a metal foil, such as Alpet (aluminum foil / polyethylene) Terephthalate film). Specifically, each material illustrated with the said flexible substrate can be used similarly.

In this invention, since an organic EL element can be made into a thin film, a resin substrate, a thin film metal foil, and a metal composite resin film can be preferably used. Furthermore, the resin substrate has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / (m ² · 24 h · atm) or less, and a method according to JIS K 7129-1992. It is preferable that the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured in (1) is 1 × 10 ⁻³ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive that forms the sealing adhesive layer (6) include acrylic and methacrylic acid oligomer photocuring and thermosetting adhesives having a reactive vinyl group, and 2-cyanoacrylic acid. Mention may be made of moisture-curing adhesives such as esters. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element unit may deteriorate with heat processing, what can be adhesive-hardened in the temperature range from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive.

  Application | coating of the adhesive agent to a sealing material may use a commercially available dispenser, and may print it like screen printing.

<< Method for Manufacturing Organic EL Device >>
In the method for producing an organic EL device of the present invention, at least an organic EL element unit and a flexible sealing plate are laminated in this order on a flexible substrate to produce a laminate, and then at least the organic EL element unit of the laminate and A side sealing layer is formed on a side surface composed of a flexible sealing plate using a side sealing layer forming material mainly composed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less. And

  As a more preferred embodiment, a gas barrier layer is formed between the flexible substrate and the organic EL element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. The gas barrier layer is formed by applying a modification treatment by vacuum ultraviolet light irradiation using a coating liquid containing polysilazane.

  Hereinafter, the manufacturing process of the organic EL device (1) having the configuration illustrated in FIG.

  (1) A gas barrier layer (7) is formed on the flexible substrate (2) by a polysilazane modification method.

  (2) An organic EL element unit (3) having a predetermined light emitting area is formed using a mask member.

  (3) A sealing adhesive layer (6) is formed on the organic EL element unit (3) and its peripheral portion by applying a sealing adhesive.

  (4) A flexible sealing plate (4) is provided on the sealing adhesive layer (6) to produce the organic EL device (1).

  (5) Cut the four sides of the produced organic EL device (1) under the condition that the final bezel width is L (mm). In this state, the distance from the end to the end of the organic EL element unit is the thickness (mm) of the L-side sealing layer.

(6) Finally, a side sealing layer containing a polymer having a surface energy of 30 × 10 ⁻³ N / m or less using a wet coater (8) on the four side portions cut by the method shown in FIG. The side surface sealing layer (5) is formed by sequentially applying and drying the forming coating solution in a state of being bonded and fixed to at least the flexible substrate.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "%" is used in an Example, unless otherwise indicated, "mass%" is represented.

Example 1
<< Production of organic EL devices >>
[Production of Organic EL Device 1]
According to the following method, the organic EL device 1 having the configuration shown in FIG. The numbers in parentheses correspond to the code numbers of the respective components described in each figure.

(Step 1) Preparation of Flexible Substrate (2) As the flexible substrate (2), thin flexible glass (thickness: 50 μm, manufactured by Corning Inc., described as thin glass in Table 1) was used.

(Step 2) Formation of Organic EL Element Unit 1 According to the following method, using a mask member, the bezel width (L) is 2 mm on the flexible substrate (2) as shown in FIG. Under the conditions, the organic EL element unit 1 (3) was formed.

<2.1: Formation of transparent anode>
On the said flexible substrate (2), the transparent anode comprised from a silver thin film was formed in accordance with the following method using the mask member.

  A thin flexible glass (2), which is a flexible substrate (2), was fixed to a substrate holder of a commercially available vacuum deposition apparatus, silver (Ag) was placed in a resistance heating boat made of tungsten, and was attached to the first vacuum chamber of the vacuum deposition apparatus. .

Next, after depressurizing the first vacuum tank to 4 × 10 ⁻⁴ Pa, the resistance heating boat containing silver was energized and heated. Thereby, a transparent anode made of silver having a thickness of 15 nm and a deposition rate of 0.1 nm / second to 0.2 nm / second was formed through a mask having a predetermined size, thereby forming a transparent anode.

<2.2: Formation of organic functional layer unit>
Subsequently, after reducing the pressure to 1 × 10 ⁻⁴ Pa using a commercially available vacuum deposition apparatus, the compound HT-1 shown below was deposited at a deposition rate of 0 while moving the flexible substrate (2) on which the transparent anode was formed. Evaporation was performed at a rate of 1 nm / second, and a 20 nm hole transport layer (HTL) was provided.

  Next, compound A-3 (blue light emitting dopant), compound A-1 (green light emitting dopant), compound A-2 (red light emitting dopant) and compound H-1 (host compound) shown below are converted into compound A-3. The vapor deposition rate is changed depending on the film formation region so that is linearly 35% to 5% by mass with respect to the film thickness. The deposition rate was changed depending on the film formation region so that the concentration of the compound H-1 was 64.6% by mass to 94.6% by mass at a deposition rate of 0.0002 nm / second so that the concentration was mass%. A light emitting layer was formed by co-evaporation so that the total layer thickness was 70 nm.

  Then, the following compound ET-1 was vapor-deposited with a film thickness of 30 nm to form an electron transport layer, and further potassium fluoride (KF) was formed with a thickness of 2 nm to form an organic functional layer unit.

<2.3: Formation of cathode>
Subsequently, aluminum 110nm was vapor-deposited, the cathode was formed, and the organic EL element unit 1 (3) was formed.

  In addition, the said compound HT-1, compound A-1 to 3, compound H-1, and compound ET-1 are the compounds shown below.

(Step 3) Application of sealing member Next, as the flexible sealing plate (4), an alpet obtained by laminating an aluminum foil with a thickness of 30 μm on a polyethylene terephthalate film having a thickness of 20 μm is used. 4) A thermosetting liquid adhesive (epoxy resin) having a thickness of 25 μm as a sealing adhesive layer (6) is applied on one side of 4) to the organic EL element unit 1 (3) formed up to the cathode. Superimposed. At this time, the surface for forming the sealing adhesive layer (6) and the surface of the organic EL element unit 1 (3) are continuously provided so that the ends of the lead electrodes of the transparent anode and the cathode (6) come out. Superimposed.

  Next, the laminate is placed in a decompression device, and a unit and a sealing member unit are formed from the flexible substrate (2) to the cathode (6) superimposed under a decompression condition of 0.1 MPa at 90 ° C. Pressed and held for 5 minutes. Subsequently, the laminate was returned to the atmospheric pressure environment, and further heated at 90 ° C. for 30 minutes to cure the adhesive, thereby producing an organic EL device unit before forming the side surface sealing layer.

  The sealing step is performed under atmospheric pressure and in a nitrogen atmosphere with a moisture content of 1 ppm or less, in accordance with JIS B 9920, with a measured cleanliness of class 100, a dew point temperature of −80 ° C. or less, and an oxygen concentration of 0.8 ppm or less. At atmospheric pressure.

(Step 4) Formation of side sealing layer The entire thickness of the four sides of the organic EL device unit produced above was dried according to the coating method shown in FIG. Formed a side sealing layer having a thickness of 20 μm, and an organic EL device 1 was produced. The distance (bezel width (L)) from the edge part of the organic EL element unit in the organic EL device 1 to the outer peripheral part of the side surface sealing layer was 2 mm.

(Coating liquid for forming side sealing layer)
Fluorosurf FG-3030C-30 (main component: perfluorooctylethyl acrylate), which is a fluororesin manufactured by Fluoro Technology, was used. In addition, the surface energy of the fluorosurf FG-3030C-30 measured by the method described later is 12 × 10 ⁻³ N / m.

[Production of Organic EL Device 2]
(Process 1) Preparation of flexible substrate (2) As the flexible substrate (2), a stainless steel foil (thickness: 70 μm, manufactured by Nippon Steel Materials Co., Ltd.) was prepared.

(Step 2) Formation of Insulating Layer On the stainless steel foil, which is the flexible substrate (2), an L-430S-FHS sputtering apparatus manufactured by Anelva was used, Ar 20 sccm, O ₂ 0 sccm, sputtering pressure 0.25 Pa, room temperature (25 The insulating layer was formed by DC pulse sputtering using polycrystalline SiO ₂ as a target and a layer thickness of 200 nm at a formation rate of 2.5 nm / s.

(Step 3) Formation of Organic EL Element Unit 2 In the formation of the organic EL element unit 1 described in the organic EL device 1 (step 2), the thickness of silver was changed to aluminum (110 nm) as the cathode formation method. The organic EL element unit 2 was formed in the same manner except that the cathode having light transmittance was formed by vapor deposition at 10 nm.

(Step 4) Application of sealing member Next, as the flexible sealing plate (4), a gas barrier film having a thickness of 250 nm formed on a polyethylene terephthalate film having a thickness of 20 μm by the following method is used. An organic EL in which a thermosetting liquid adhesive (epoxy resin) is applied as a sealing adhesive layer (6) to a thickness of 25 μm on one side of the flexible sealing plate (4) to form a cathode. Overlaid on the element unit 2 (3). At this time, the surface for forming the sealing adhesive layer (6) and the surface of the organic EL element unit 2 (3) are continuously provided so that the ends of the lead electrodes of the transparent anode and the cathode (6) come out. Superimposed.

(Formation of gas barrier layer)
After applying the following polysilazane-containing coating solution to form a coating film, a modification treatment by vacuum ultraviolet irradiation was performed, and a gas barrier layer was formed by a polysilazane modification method.

<Preparation of polysilazane-containing coating solution>
A dibutyl ether solution containing 20% by mass of perhydropolysilazane (PHPS) (manufactured by AZ Electronic Materials, NN120-20) and an amine catalyst (N, N, N ′, N′-tetramethyl-1,6-diamino) Hexane (TMDAH))-containing perhydropolysilazane 20% by mass dibutyl ether solution (manufactured by AZ Electronic Materials Co., Ltd., NAX120-20) is mixed at a ratio of 4: 1 (mass ratio) and further dried film thickness For adjustment, it was appropriately diluted with dibutyl ether to prepare a polysilazane-containing coating solution.

<Coating formation and modification treatment>
The prepared polysilazane-containing coating solution was applied on a PET film by a spin coating method under the condition that the dry film thickness was 250 nm, and dried at 80 ° C. for 2 minutes. Next, the dried coating film was subjected to a vacuum ultraviolet ray irradiation treatment using a Xe excimer lamp with a wavelength of 172 nm under the conditions of oxygen concentration: 0.1% by volume and irradiation energy: 6.0 J / m ^2. A barrier layer (7) was formed.

  Next, the laminate is placed in a decompression device, and a unit and a sealing member unit are formed from the flexible substrate (2) to the cathode (6) superimposed under a decompression condition of 0.1 MPa at 90 ° C. Pressed and held for 5 minutes. Subsequently, the laminate was returned to the atmospheric pressure environment, and further heated at 90 ° C. for 30 minutes to cure the adhesive, thereby producing an organic EL device unit before forming the side surface sealing layer.

(Step 5) Formation of side surface sealing layer In the same manner as the method used in the organic EL device 1 for the produced organic EL device unit, a thickness of 20 μm made of a fluororesin (Fluorosurf FG-3030C-30) is used. An organic EL device 2 was produced by forming a side sealing portion.

[Production of Organic EL Device 3]
(Step 1) Preparation of flexible substrate (2) As flexible substrate (2), double-sided hard-coated polyethylene terephthalate film (total thickness: 136 μm, polyethylene terephthalate thickness: 125 μm, manufactured by Kimoto Co., Ltd., trade name: KB film (trademark) ) 125G1SBF, hereinafter abbreviated as PET film).

(Step 2) Formation of gas barrier layer (7) After applying a polysilazane-containing coating solution prepared by the following method to form a coating film, a reforming treatment by vacuum ultraviolet irradiation is performed, and a gas is formed by a polysilazane reforming method. A barrier layer (7) was formed.

<Preparation of polysilazane-containing coating solution>
A dibutyl ether solution containing 20% by mass of perhydropolysilazane (PHPS) (manufactured by AZ Electronic Materials, NN120-20) and an amine catalyst (N, N, N ′, N′-tetramethyl-1,6-diamino) Hexane (TMDAH))-containing perhydropolysilazane 20% by mass dibutyl ether solution (manufactured by AZ Electronic Materials Co., Ltd., NAX120-20) is mixed at a ratio of 4: 1 (mass ratio) and further dried film thickness For adjustment, it was appropriately diluted with dibutyl ether to prepare a polysilazane-containing coating solution.

<Coating formation and modification treatment>
The prepared polysilazane-containing coating solution was applied on a PET film by a spin coating method under the condition that the dry film thickness was 250 nm, and dried at 80 ° C. for 2 minutes. Next, the dried coating film was subjected to vacuum ultraviolet irradiation treatment using a Xe excimer lamp with a wavelength of 172 nm under the conditions of oxygen concentration: 0.1 vol% and irradiation energy: 6.0 J / m ^2. A gas barrier layer (7) having a thickness of 200 nm was formed.

(Step 3) to (Step 5)
In the same manner as in the production of the organic EL device 2, (Step 3) formation of an organic EL element unit, (Step 4) application of a sealing member, and (Step 5) formation of a side surface sealing layer are performed. 3 was produced.

[Production of Organic EL Device 4]
In the production of the organic EL device 3, (Step 2) The organic EL device 4 was produced in the same manner except that the formation of the gas barrier layer (7) was performed by the following sputtering method instead of the polysilazane modification method. .

(Step 2) Formation of gas barrier layer (7): Sputtering method An Aruba L-430S-FHS sputtering apparatus is used on the upper PET film which is the flexible substrate (2), Ar 20 sccm, O ₂ 0 sccm, sputtering pressure At 0.25 Pa, room temperature (25 ° C.), with a formation rate of 2.5 nm / s, polycrystalline SiO ₂ is used as a target, and DC pulse sputtering is performed under the condition that the layer thickness is 200 nm, thereby forming a gas barrier layer (7). did.

[Production of Organic EL Device 5]
In the production of the organic EL device 4, (Step 5) The organic EL device 5 was produced in the same manner except that the formation of the side surface sealing layer was changed to the following method.

(Step 5) Formation of side surface sealing layer 10 parts by weight of polyvinyl alcohol (manufactured by Kuraray Kogyo Co., Ltd .: PVA235) is mixed with 90 parts by weight of water, allowed to stand for 10 minutes, and then heated to 90 ° C to obtain polyvinyl alcohol. A coating solution (PVA coating solution) was prepared.

  Next, as shown in FIG. 3B, the PVA coating solution is applied to the entire side surface of the organic EL device unit by a spray coating method under the condition that the layer thickness after drying is 50 μm, The formed coating film was dried and cured at 100 ° C. to form a side surface sealing layer (5) composed of PVA.

[Production of Organic EL Device 6]
In the production of the organic EL device 4, (Step 5) An organic EL device 6 was produced in the same manner except that the formation of the side surface sealing layer was changed to the following method.

(Step 5) Formation of side sealing layer 7 parts by mass of polyvinyl alcohol (manufactured by Kuraray Kogyo Co., Ltd .: PVA235), 3 parts by mass of vapor phase silica (Aerosil 200V, Nippon Aerosil Co., Ltd.), and 90 parts by mass of water were mixed. After leaving still for 10 minutes, the temperature was heated to 90 ° C. and then subjected to a dispersion treatment to prepare a polyvinyl alcohol / silica mixed coating solution (PVA / silica coating solution).

Next, as shown in FIG. 3B, the PVA / silica coating solution is applied to the entire side surface of the organic EL device unit by a spray coating method under the condition that the layer thickness after drying is 50 μm. Next, the formed coating film was dried and cured at 100 ° C. to form a side surface sealing layer (5) composed of PVA and silica (SiO ₂ ).

[Production of Organic EL Device 7]
In the production of the organic EL device 3, (step 5) the side surface sealing layer (5) is formed of PVA and silica (SiO ₂ ) in the same manner as the production of the organic EL device 6 in the formation of the side surface sealing layer. An organic EL device 7 was produced in the same manner except that was formed.

<< Measurement and evaluation of each characteristic >>
(Measurement of surface energy of side sealing layer forming member)
The surface energy of each polymer was measured according to the following method.

(Preparation of sample plate for measurement)
After preparing the polymer solution which melt | dissolved the fluororesin (fluorosurf FG-3030C-30) and polyvinyl alcohol (made by Kuraray Industrial Co., Ltd .: PVA235) which are measuring objects with a suitable solvent, respectively, the said polymer solution is made into flat glass. After applying and drying on the substrate under the condition that the thickness after drying was 50 μm, humidity was adjusted for 1 day in an environment of 25 ° C. and 55% RH to prepare a measurement plate.

(Measurement of surface energy)
The surface energy is measured using a FACE contact angle meter CA-D type (manufactured by Kyowa Interface Science Co., Ltd.) in an environment of 25 ° C. and 55% RH on a measurement plate with ethylene glycol, n-hexadecane, and iodide. Methylene was added dropwise in an amount of 3 μl each as a droplet amount, each contact angle was measured, and the surface energy (mN / m) was calculated from the value and Young-Fowkes equation.

(Evaluation of preservability: resistance to dark spots in high temperature and high humidity environment)
Each organic EL element device was stored for 50 hours in an environment of 85 ° C. and 85% RH. Thereafter, a current of 1 mA / cm ² was applied to emit light. Subsequently, it image | photographed about the area | region of width 2cm from the edge part of an organic EL element with the 100 times optical microscope (Mortex Co., Ltd. product MS-804, lens MP-ZE25-200). Next, the dark spot generation area ratio in an area of 2 cm wide × 2 cm long from the end portion was measured at 12 random locations on four sides, the average value was obtained, and darkness due to moisture permeation from the end portion was determined according to the following criteria: Spot resistance was evaluated.

5: The area where dark spots are generated is less than 0.1% 4: The area where dark spots are generated is 0.1% or more and less than 1.0% 3: The area where dark spots are generated is 1.0 % Or more and less than 2.5% 2: Dark spot generation area is 2.5% or more and less than 5.0% 1: Dark spot generation area is 5.0% or more [Bending Resistance evaluation)
Each organic EL element device was stored for 50 hours in an environment of 85 ° C. and 85% RH in a state where the organic EL element device was wound around a plastic roller having a curvature of 6 mmφ so that the organic EL element forming surface was on the outside. Thereafter, a current of 1 mA / cm ² was applied to emit light. Subsequently, it image | photographed about the area | region of width 2cm from the edge part of an organic EL element with the 100 times optical microscope (Mortex Co., Ltd. product MS-804, lens MP-ZE25-200). Subsequently, the dark spot generation area ratio in a region of 2 cm wide × 2 cm long from the end was measured at 12 random locations on four sides, the average value was obtained, and bending resistance was evaluated according to the following criteria.

5: The area where dark spots are generated is less than 0.1% 4: The area where dark spots are generated is 0.1% or more and less than 1.0% 3: The area where dark spots are generated is 1.0 % Or more and less than 2.5% 2: Dark spot generation area is 2.5% or more and less than 5.0% 1: Dark spot generation area is 5.0% or more The obtained results are shown in Table 1.

As is clear from the results shown in Table 1, the organic EL device of the present invention in which the side surface sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less is compared with the comparative example from the end. In the organic EL device having a flexible substrate and a flexible sealing plate, by providing a side sealing layer made of a polymer with excellent flexibility, the followability to bending and the like is high. It can be seen that it has excellent bending resistance.

Example 2
<< Production of organic EL devices >>
[Production of Organic EL Devices 8 and 9]
In the production of the organic EL device 3 described in Example 1, except that the bezel width from the outer periphery of the side sealing layer to the end of the organic EL element unit was changed from 2.0 mm to 1.0 mm and 0.5 mm, respectively. Similarly, organic EL devices 8 and 9 were produced.

[Production of Organic EL Devices 10 and 11]
In the production of the organic EL device 7 described in Example 1, the bezel width from the outer peripheral portion of the side sealing layer to the end of the organic EL element unit was changed from 2.0 mm to 1.0 mm and 0.5 mm, respectively. Similarly, organic EL devices 10 and 11 were produced.

<< Evaluation of organic EL devices >>
For the organic EL devices 8 to 11 produced above and the organic EL devices 3 and 7 produced in Example 1, storage stability and bending resistance were evaluated in the same manner as in the method described in Example 1 and obtained. The results are shown in Table 2.

As is clear from the results shown in Table 2, the organic EL device of the present invention in which the side surface sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less has a bezel width as compared with the comparative example. It can be seen that even if it is narrowed, it has an excellent effect on storage stability and bending resistance.

Example 3
<< Production of organic EL devices >>
[Production of organic EL devices 12 to 21]
In the production of the organic EL device 3 described in Example 1, organic EL devices 12 to 21 were produced in the same manner except that the material for forming the side surface sealing layer was changed to the polymer described in Table 3.

<< Evaluation of organic EL devices >>
About the produced organic EL devices 12 to 21 and the organic EL device 3 produced in Example 1, in the same manner as in the method described in Example 1, storage stability and bending resistance were evaluated, and the obtained results were obtained. Table 3 shows.

As is clear from the results shown in Table 3, the organic EL device of the present invention in which the side surface sealing layer is formed of a polymer having a surface energy of 30 × 10 ⁻³ N / m or less is more stable than the comparative example. It turns out that it has the effect excellent in bending tolerance. Among these, it can be seen that the organic EL device of the present invention in which the side sealing layer is formed of a fluorine-based polymer having a surface energy of 20 × 10 ⁻³ N / m or less exhibits a more excellent effect.

DESCRIPTION OF SYMBOLS 1 Organic EL device 2 Flexible substrate 3 Organic EL element unit 4 Flexible sealing board 5 Side surface sealing layer 6 Sealing adhesive layer 7, 7A, 7B Gas barrier layer 8 Wet coater 9 Side surface sealing layer forming coating liquid L Bezel width M Laminate

Claims (10)

An organic electroluminescence device having a laminate in which at least an organic electroluminescence element unit and a flexible sealing plate are laminated in this order on a flexible substrate,
Having a side surface sealing layer on a side surface part of a laminate composed of at least the organic electroluminescence element unit and the flexible sealing plate;
The said side surface sealing layer is formed with the polymer whose surface energy is 30 * 10 < ^-3 > N / m or less as a main component, The organic electroluminescent device characterized by the above-mentioned. 2. The organic electroluminescent device according to claim 1, wherein the polymer contained in the side surface sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less.   The organic electroluminescence device according to claim 1, wherein at least a part of the side surface sealing layer is bonded and fixed to the flexible substrate.   The gas barrier layer is provided between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. The organic electroluminescent device according to any one of claims 1 to 3.   The organic electroluminescence device according to claim 4, wherein the gas barrier layer is a polysilazane modified layer. After producing a laminate by laminating at least an organic electroluminescence element unit and a flexible sealing plate in this order on a flexible substrate,
A side surface sealing layer forming material whose main component is a polymer having a surface energy of 30 × 10 ⁻³ N / m or less on a side surface portion composed of at least the organic electroluminescence element unit and the flexible sealing plate of the laminate. A method for producing an organic electroluminescent device, comprising forming a side sealing layer using The method for producing an organic electroluminescent device according to claim 6, wherein the polymer used for forming the side sealing layer is a fluorine-containing polymer having a surface energy of 20 × 10 ⁻³ N / m or less.   The method for manufacturing an organic electroluminescence device according to claim 6, wherein at least a part of the side surface sealing layer is bonded and fixed to the flexible substrate.   The gas barrier layer is formed between the flexible substrate and the organic electroluminescence element unit, and at least a part of the side surface sealing layer is bonded and fixed to the gas barrier layer. Item 9. The method for producing an organic electroluminescence device according to any one of Items 8 to 8.   The method for producing an organic electroluminescent device according to claim 9, wherein the gas barrier layer is formed by applying a modification treatment by vacuum ultraviolet light irradiation using a coating liquid containing polysilazane.

Images