JPWO2014041615A1 - Organic EL device - Google Patents

Abstract

Provided is an organic EL device which has flexibility and can obtain good sealing performance. The organic EL device 1 includes a flexible substrate 2, a light emitting unit 10 formed on one side of the substrate 2, and a sealing member 3 that covers the light emitting unit 10. The light emitting unit 10 includes one or a plurality of organic EL elements. The sealing member 3 includes a flexible member 32 and a plurality of drying members 31, and the plurality of drying members 31 are arranged at different positions on the light emitting unit 10.

Description

  The present invention relates to an organic EL device.

  In order to seal an EL layer, it is known to use a laminate film in which a resin film is stacked (see Patent Document 1 below).

JP-A-61-290693

  Thin light emitting devices having flexibility are required for various applications. In particular, a display panel of a portable electronic device is required to have flexibility in order to suppress damage due to pressure when being carried.

  An object of the present invention is to provide an organic EL device which has flexibility and can obtain good sealing performance.

  In order to achieve such an object, the organic EL device according to the present invention has at least the following configuration.

  A substrate having flexibility, a light emitting portion formed on one side of the substrate, and a sealing member covering the light emitting portion, the light emitting portion including one or a plurality of organic EL elements, and the sealing The member includes a flexible member and a plurality of drying members, and the plurality of drying members are arranged at different positions on the light emitting unit.

FIG. 1 is an explanatory diagram showing an organic EL device according to an embodiment of the present invention (FIG. 1A is an explanatory diagram showing a cross-sectional structure, and FIG. 1B is an explanatory diagram viewed from above). The structural example of the organic EL element in the light emission part of the organic EL apparatus which concerns on embodiment of this invention is shown. It is explanatory drawing which showed the cross-sectional structural example of the desiccant layer in the organic electroluminescent apparatus which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing an organic EL device according to an embodiment of the present invention (FIG. 1 (a) is an explanatory view showing a cross-sectional structure, and FIG. 1 (b) is an explanatory view in plan view. is there.). The organic EL device 1 includes a flexible substrate (for example, a film substrate) 2, a light emitting unit 10 formed on one side of the substrate 2, and a sealing member 3 that covers the light emitting unit 10. The sealing member 3 has flexibility similar to the substrate 2, and the organic EL device 1 as a whole has flexibility. As the board | substrate 2, the member which can be bent with a resin film, a glass film, a metal film etc. can be used.

  The sealing member 3 includes at least a flexible member 32 and a plurality of drying members 31. In the illustrated example, the plurality of drying members 31 are covered with a flexible member 32. Moreover, the resin layer 30 which contacts the light emission part 10 is provided as needed. A connecting member 33 for connecting the plurality of drying members 31 and the flexible member 32 can be provided. As the resin layer 30 here, for example, an ultraviolet curable resin, specifically, a known resin such as an epoxy resin can be used. As the member 32 having flexibility, a bendable member such as a resin film, a glass film, or a metal film can be used. Examples of each drying member 31U in the plurality of drying members 31 include oxides such as BaO, SrO, and CaO having a moisture absorption function, or a mixture of an oxide and a resin.

  The plurality of drying members 31 are disposed on the light emitting unit 10 between the resin layer 30 and the flexible member 32. In the illustrated example, the resin layer 30 is disposed in the region of the layer formed by the connecting member 33. And each drying member 31U is arrange | positioned in the different position on the light emission part 10, and is arrange | positioned mutually spaced apart. In the example shown in FIG. 1B, a plurality of dividing lines that connect the gaps between the adjacent drying members 31U are arranged vertically and horizontally and arranged in a lattice pattern. However, the present invention is not limited to this, and the dividing lines may be arranged one by one vertically and horizontally. Further, the gap between the two drying members 31U may be filled with a member constituting the resin layer 30 or the connecting member 33.

  According to such an organic EL device 1, the flexible organic EL device 1 can be obtained by sandwiching the light emitting unit 10 between the flexible substrate 2 and the sealing member 3. Since the sealing member 3 has a plurality of drying members 31 disposed between the resin layer 30 and the flexible member 32, the drying member 31 removes moisture generated from the resin layer 30 and the flexible member 32. By adsorbing, the sealing property of the light emitting unit 10 can be improved. Since each drying member 31U is arrange | positioned in the position which mutually differs, or is arrange | positioned separately, favorable moisture adsorption | suction performance can be exhibited, without impairing the flexibility of the sealing member 3. FIG. Since the resin layer 30 functions as a protective layer for the light emitting unit 10, it is possible to solve the problem that the drying member 31 </ b> U that has expanded by adsorbing moisture directly contacts the light emitting unit 10 to cause leakage.

  In the example shown in FIG. 1B, a plurality of dividing lines passing between the adjacent drying members 31U are arranged vertically and horizontally and arranged in a lattice pattern. According to this, since there are a plurality of dividing lines along the direction in which the drying members 31U are arranged, the sealing member 3 can be curved along the plurality of dividing lines, and the flexibility of the sealing member 3 is ensured. can do. Note that the dividing lines are not limited to such a grid-like arrangement, and may be, for example, a random arrangement or an arrangement of dividing lines along a direction in which the dividing line is desired to be curved.

  FIG. 2 shows a configuration example of the organic EL element in the light emitting unit. The organic EL element 10U includes a first electrode 11 formed on the substrate 2, an organic layer 12 formed on the first electrode 11 and including the light emitting layer 12a, and a second electrode 13 formed on the organic layer 12. Yes. The organic EL element 10U may be divided into a plurality of light emitting units by an insulating film 14 as shown in the figure, or may be a single light emitting element spread so that surface emission of a desired area can be obtained. Good.

  The light emitting unit 10 can employ a passive matrix driving method or an active matrix driving method. The light emitting unit 10 may employ either a bottom emission method in which light is extracted from the substrate 2 side or a top emission method in which light is extracted from the side opposite to the substrate 2. When the bottom emission method is adopted, a light transmissive material is used for the first electrode 11 and the substrate 2, and when the top emission method is adopted, a light transmissive material is used for the second electrode 13 and the sealing member 3. Used.

  FIG. 3 is an explanatory view showing a cross-sectional configuration example of the drying member. For example, as shown in the drawing, the drying member 31 has a laminated structure composed of an adhesive 31a as a connecting member, a resin film 31b, an adhesive 31c as a connecting member, a sheet-shaped drying agent 31d, and an adhesive 31e as a connecting member. be able to. Moreover, it can also be set as the 3 layer structure which laminated | stacked the adhesive on both surfaces of the sheet-like desiccant. The sheet-like desiccant may be constituted by, for example, a resin and a member in which the above-described oxide is mixed in the resin.

  Below, the specific structural example of the organic EL element 10U mentioned above is demonstrated.

The first electrode 11 is a transparent conductive film in the case of the bottom emission method, and includes ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), a zinc oxide-based transparent conductive film, a SnO ₂ -based transparent conductive film, and a titanium dioxide-based transparent film. A transparent metal oxide such as a conductive film can be used. The first electrode 11 can be formed on the substrate 2 directly or via another layer.

  In the case where the first electrode 11 is patterned on a plurality of electrodes, an insulating film 14 is provided to ensure insulation between the electrodes. The insulating film 14 is made of a material such as polyimide resin, acrylic resin, silicon oxide, or silicon nitride. The insulating film 14 is formed in a lattice shape when the organic EL elements 10U are arranged in a dot matrix shape.

  The organic layer 12 has a laminated structure of light emitting functional layers including the light emitting layer 12a. When one of the first electrode 11 and the second electrode 13 is an anode and the other is a cathode, the hole injection layer, A hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like are selectively formed. As the film formation of the organic layer 12, a vacuum deposition method or the like is used as a dry film formation, and coating or various printing methods are used as a wet film formation.

  An example of forming the organic layer 12 will be described below. For example, first, NPB (N, N-di (naphtalence) -N, N-dipheneyl-benzidene) is formed as a hole transport layer. This hole transport layer has a function of transporting holes injected from the anode to the light emitting layer. The hole transport layer may be a single layer or a stack of two or more layers. In addition, the hole transport layer is not formed by a single material, but a single layer may be formed by a plurality of materials, and a guest material having a high charge donating (accepting) property may be formed on a host material having a high charge transport capability. Doping may be performed.

  Next, a light emitting layer is formed on the hole transport layer. As an example, red (R), green (G), and blue (B) light-emitting layers are formed in respective film formation regions by using a resistance heating vapor deposition method using a coating mask. As the red (R), an organic material that emits red light such as a styryl dye such as DCM1 (4- (dicyanomethylene) -2-methyl-6- (4'-dimethylaminostyryl) -4H-pyran) is used. An organic material that emits green light such as an aluminum quinolinol complex (Alq3) is used as green (G). As the blue (B), an organic material emitting blue light such as a distyryl derivative or a triazole derivative is used. Of course, other materials or a host-guest layer structure may be used, and the emission form may be a fluorescent light emitting material or a phosphorescent light emitting material.

  The electron transport layer formed on the light emitting layer is formed using various materials such as an aluminum quinolinol complex (Alq3) by various film forming methods such as resistance heating vapor deposition. The electron transport layer has a function of transporting electrons injected from the cathode to the light emitting layer. This electron transport layer may have a multilayer structure in which only one layer is stacked or two or more layers are stacked. In addition, the electron transport layer may be formed of a plurality of materials instead of a single material, and a guest material having a high charge donating (accepting) property may be formed on a host material having a high charge transport capability. It may be formed by doping.

When the second electrode 13 formed on the organic layer 12 is a cathode, a material (metal, metal oxide, metal fluoride, alloy, or the like) having a work function smaller than that of the anode (for example, 4 eV or less) is used. Specifically, metal films such as aluminum (Al), indium (In), magnesium (Mg), amorphous semiconductors such as doped polyaniline and doped polyphenylene vinylene, Cr ₂ O ₃ , An oxide such as NiO or Mn ₂ O ₅ can be used. As the structure, a single layer structure made of a metal material, a laminated structure of LiO ₂ / Al, or the like can be adopted.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention. The embodiments described in the above drawings can be combined with each other as long as there is no particular contradiction or problem in the purpose, configuration, or the like. Moreover, the description content of each figure can become independent embodiment, respectively, and embodiment of this invention is not limited to one embodiment which combined each figure.

Claims (7)

A substrate having flexibility, a light emitting part formed on one side of the substrate, and a sealing member covering the light emitting part,
The light emitting unit includes one or a plurality of organic EL elements,
The sealing member includes a flexible member and a plurality of drying members,
The organic EL device, wherein the plurality of drying members are arranged at different positions on the light emitting unit.   The organic EL device according to claim 1, wherein the sealing member has flexibility.   The organic EL device according to claim 2, wherein the drying members of the plurality of drying members are separated from each other.   The organic EL device according to claim 3, wherein a resin layer is provided between the light emitting unit and the drying member.   The organic EL device according to claim 3, wherein the plurality of drying members and the flexible member are connected by a connecting member.   The organic EL device according to claim 5, wherein the plurality of drying members are covered with the flexible member.   The plurality of drying members are disposed between the resin layer and the connecting member, and the resin layer is disposed in a region of a layer formed by the connecting member. Item 7. The organic EL device according to Item 6.

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