JP2018117035A - Organic electroluminescence device - Google Patents

Abstract

Kind Code: A1 A solvent contained in a composition for forming an organic layer is prevented from dissolving or permeating into another organic layer when forming an organic layer using a coating method. A first electrode layer (2) on one surface of a substrate (1) and an organic EL device on a surface of the first electrode layer (2) opposite to the substrate (1), including a plurality of organic layers including a light-emitting layer. An organic EL element having a layer 3 and a second electrode layer 4 on the surface of the organic EL layer 3 opposite to the first electrode layer 2, wherein the first electrode layer 2 is the most first electrode layer 2 among the plurality of organic layers. When the organic layer located on the side is defined as a first organic layer, the first organic layer covers the surface and the side surface of the first electrode layer on the first organic layer side, and is the first organic layer among the plurality of organic layers. When any one of the organic layers located on the second electrode layer side of one organic layer is defined as the second organic layer, the second organic layer is formed on the surface of the second organic layer on the first electrode layer 2 side. An organic EL element covering the surface of the contacting organic layer on the side of the second organic layer and the side surface of the organic layer positioned from the second organic layer to the first electrode layer 2 side among the plurality of organic layers. [Selection drawing] Fig. 1

Description

  Embodiments of the present disclosure relate to an organic electroluminescent device having a coating-type organic layer.

  The organic electroluminescence element has high visibility due to self-coloring, is an all-solid-state display unlike a liquid crystal display device, has excellent impact resistance, has a fast response speed, is less affected by temperature changes, and Advantages such as a wide viewing angle are attracting attention. Hereinafter, organic electroluminescence may be abbreviated as organic EL.

  The organic EL element usually has a configuration in which an organic EL layer composed of a plurality of organic layers including a transparent substrate, a transparent first electrode layer, and a light emitting layer, and a second electrode layer are sequentially laminated. Here, there are roughly two methods for forming the organic EL layer. Specific examples include a dry process method in which a film is formed by vapor deposition under vacuum and a coating method in which a film is formed by applying a composition for forming an organic EL layer. In recent years, attention has been focused on the use of an organic EL element as a lighting device, and a large area and high productivity of the organic EL element are demanded. Therefore, as a method for forming the organic EL layer, a coating method is more preferably used from the viewpoint of an increase in area and productivity.

  When the organic EL layer is formed by a coating method, that is, when a plurality of organic layers constituting the organic EL layer are formed by a coating method, the solvent contained in the composition for forming the organic layer is the organic layer. There is a problem that the organic layer is dissolved and penetrated into another organic layer located on the first electrode layer side to be deteriorated. Therefore, for example, as shown in FIG. 5, an organic EL element 10 ′ in which a transparent substrate 1, a first electrode layer 2, an organic EL layer 3, and a second electrode layer 4 are sequentially laminated, In the case of the organic EL device 10 ′ having the hole injection layer 31, the hole transport layer 32, the light emitting layer 33, and the electron transport layer 34, a solvent used in the composition for forming the hole transport layer 32 For the solvent used for the composition for forming the light-emitting layer 33, a material that is difficult to dissolve and penetrate into the hole transport layer 32 is used. Furthermore, it is preferable to use a material that is difficult to dissolve and penetrate into the light emitting layer 33 as the solvent used in the composition for forming the electron transport layer 34. That is, as the solvent contained in the composition for forming the organic layer, it is preferable to select a material that is difficult to dissolve and penetrate into the organic layer located on the first electrode layer side.

JP 2004-296417 A JP 2006-012433 A

  Thus, the solvent contained in the composition for forming the conventional organic layer is a material that is difficult to dissolve and penetrate into the organic layer that is in contact with the organic layer, that is, the so-called organic layer located immediately below the first electrode layer. Although there is a tendency to be used, such a material is not necessarily a material that hardly dissolves and permeates into other organic layers other than the organic layer immediately below the organic layer. Therefore, for example, as indicated by an arrow shown in FIG. 5, the organic solvent that is included in the composition for forming the organic layer is in contact with the organic layer on the surface on the first electrode layer side from the side surface of the organic EL layer 3. The subject that it melt | dissolves and osmose | permeates other organic layers other than a layer arises. Specifically, in the case of the organic EL element 10 ′ illustrated in FIG. 5, for example, a problem that the solvent used in the composition for forming the light emitting layer 33 is dissolved and permeated into the hole injection layer 31. In addition, there is a problem that the solvent used in the composition for forming the electron transport layer 34 is dissolved and penetrated into the hole transport layer 32 and the hole injection layer 31. Patent Documents 1 and 2 propose a technique related to a waterproof layer for suppressing moisture permeation into the organic EL layer.

  The present disclosure has been made in view of the above problems, and when forming an organic layer using a coating method, the solvent contained in the composition for forming an organic layer dissolves and penetrates into another organic layer. It is a main object to provide an organic EL element capable of suppressing the above.

  One embodiment of the present disclosure includes a substrate, a first electrode layer on one side of the substrate, and a plurality of organic layers including a light emitting layer, opposite to the substrate of the first electrode layer. An organic EL element having an organic EL layer on a side surface and a second electrode layer on a surface opposite to the first electrode layer of the organic EL layer, wherein the organic EL element includes: When the organic layer located closest to the first electrode layer is the first organic layer, the first organic layer has a surface and a side surface of the first electrode layer on the first organic layer side. When the second organic layer is any one of the plurality of organic layers that is positioned on the second electrode layer side of the first organic layer, the second organic layer is The second organic layer side surface of the organic layer in contact with the first electrode layer side surface of the second organic layer, and the second of the plurality of organic layers From machine layer to provide an organic EL element which covers the side surface of the organic layer located on the first electrode layer side.

  In one embodiment of the present disclosure, when the organic layer is formed on the second electrode layer side of the second organic layer using a coating method, the solvent contained in the composition for forming the organic layer is There exists an effect that it can suppress melt | dissolving and osmose | permeating into the side surface of the organic layer formed in the 1st electrode layer side of the 2nd organic layer.

It is a schematic sectional drawing which shows an example of the organic EL element of this indication. It is a schematic sectional drawing which shows the other example of the organic EL element of this indication. It is a schematic sectional drawing which shows the other example of the organic EL element of this indication. It is a schematic sectional drawing which shows the other example of the organic EL element of this indication. It is a schematic sectional drawing which shows an example of the conventional organic EL element.

  In this specification, when a certain configuration such as a certain member or a certain region is “above (or below)” another configuration such as another member or another region, unless otherwise limited, This includes not only when directly above (or directly below) another configuration, but also when above (or below) another configuration, i.e., another configuration above (or below) another configuration. This includes cases where elements are included.

  Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, the present disclosure can be implemented in many different modes, and should not be construed as being limited to the description of the embodiments described below. Further, in order to clarify the description, the drawings may be schematically represented with respect to the width, thickness, shape, etc. of each part as compared with the embodiment, but are merely examples, and the interpretation of the present disclosure may be interpreted. It is not limited. In addition, in the present specification and each drawing, elements similar to those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description may be omitted as appropriate. Further, for convenience of explanation, the description may be made using the terms “upper” or “lower”, but the vertical direction may be reversed.

  Hereinafter, the organic EL element in one embodiment of the present disclosure will be described.

  The organic EL element of the present disclosure includes a base material, a first electrode layer on one surface of the base material, and a plurality of organic layers including a light emitting layer, and is opposite to the base material of the first electrode layer. An organic EL element having an organic EL layer on a side surface and a second electrode layer on a surface opposite to the first electrode layer of the organic EL layer, wherein the organic EL element includes: When the organic layer located closest to the first electrode layer is the first organic layer, the first organic layer has a surface and a side surface of the first electrode layer on the first organic layer side. When the second organic layer is any one of the plurality of organic layers that is positioned on the second electrode layer side of the first organic layer, the second organic layer is , The second organic layer side surface of the organic layer in contact with the first electrode layer side surface of the second organic layer, and the second of the plurality of organic layers The organic layer covers the side surface of the organic layer located on the first electrode layer side.

The organic EL element of the present disclosure will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view illustrating an example of the organic EL element of the present disclosure. As illustrated in FIG. 1, the organic EL element 10 of the present disclosure includes a base material 1, a first electrode layer 2 on one surface of the base material 1, and a plurality of organic layers including a light emitting layer. It has the organic EL layer 3 on the surface on the opposite side to the base material 1 of the 1 electrode layer 2, and the 2nd electrode layer 4 on the surface on the opposite side to the 1st electrode layer 2 of the organic EL layer 3. Further, in the organic EL element 10 of the present disclosure, when the organic layer located closest to the first electrode layer 2 among the plurality of organic layers is the first organic layer, the first organic layer is the first electrode. The first organic layer side surface and the side surface of the layer are covered, and among the plurality of organic layers, any one of the organic layers located on the second electrode layer side of the first organic layer is a second When the organic layer is formed, the second organic layer includes the second organic layer-side surface of the organic layer in contact with the surface of the second organic layer on the first electrode layer 2 side, and the plurality of organic layers. The side surface of the organic layer located on the first electrode layer 2 side from the second organic layer is covered. In the organic EL element 10 shown in FIG. 1, the organic EL layer 3 is a laminate in which a hole injection layer 31, a hole transport layer 32, a light emitting layer 33, and an electron transport layer 34 are sequentially laminated. The organic layer corresponds to the hole injection layer 31, and the second organic layer corresponds to any of the hole transport layer 32, the light emitting layer 33, and the electron transport layer 34. In FIG. 1, for example, when the positive electrode transport layer 32 is the second organic layer, the hole transport layer 32 includes the surface of the hole injection layer 31 on the side in contact with the hole transport layer 32 and the hole injection layer 31. Cover the sides. In FIG. 1, for example, when the light emitting layer 33 is a second organic layer, the light emitting layer 33 is an organic layer in contact with the surface of the light emitting layer 33 on the hole injection layer 31 side, that is, the hole transport layer 32. The surface on the light emitting layer 33 side and the organic layer located on the hole injection layer 31 side from the light emitting layer 33, that is, the side surfaces of the hole transport layer 32 and the hole injection layer 31 are covered.
In the example shown in FIG. 1, an example is shown in which each organic layer constituting the organic EL layer 3 is arranged so as to cover the organic layer located on the first electrode layer side of each organic layer. Yes. Further, FIG. 1 shows an example in which the second electrode layer 4 has a function as the electron injection layer 35.

  As shown in FIG. 5, the conventional organic EL element 10 ′ is formed by sequentially forming a hole injection layer 31, a hole transport layer 32, a light emitting layer 33 and an electron transport layer 34 as an organic EL layer 3 using a coating method. For example, the solvent contained in the composition for forming the hole transport layer 32 may not dissolve or penetrate into the hole injection layer 31 located on the first electrode layer 2 side of the hole transport layer 32. It is considered preferable to select a suitable solvent. This is because the function of the organic layer is lowered due to dissolution and penetration by the solvent, and the function as the organic EL element may be impaired. In FIG. 5, as described above, the solvent contained in the composition for forming the organic layer is difficult to dissolve and penetrate into the hole injection layer 31 located on the first electrode layer side of the organic layer. In addition, for example, as a solvent contained in the composition for forming the light emitting layer 33, for example, dissolved in the hole transport layer 32 located on the first electrode layer side of the light emitting layer 33, A solvent that does not permeate is selected, and does not dissolve or permeate into the light emitting layer 33 located on the first electrode layer side of the electron transport layer 34 as a solvent contained in the composition for forming the electron transport layer 34. Such a solvent may be selected.

  By the way, in the conventional organic EL element 10 ′, as described above, as a solvent contained in the composition for forming the organic layer, dissolution and penetration into the organic layer located on the first electrode layer side of the organic layer. The material which suppresses is selected. That is, conventionally, in the organic EL layer 3, dissolution and penetration by a solvent into the organic layer located on the first electrode layer 2 side in contact with the thickness direction has been a problem. Therefore, the solvent contained in the composition for forming the organic layer has the property that it is difficult to dissolve and penetrate only into the organic layer located on the first electrode layer side of the organic layer. In the present situation, the dissolution and penetration of the organic layer into the organic layer has not been studied.

  On the other hand, as shown in FIG. 5, when a plurality of organic layers are stacked, the side surfaces of the organic layers may be exposed. Therefore, in the present disclosure, the solvent contained in the composition for forming the organic layer is difficult to dissolve and penetrate into the organic layer located on the first electrode layer side of the organic layer, but other than the organic layer. The other organic layer was found to have a problem of dissolving and penetrating from the side. Specifically, in the case of the organic EL element 10 ′ illustrated in FIG. 5, for example, a problem that the solvent used in the composition for forming the light emitting layer 33 is dissolved and permeated into the hole injection layer 31. In addition, there is a problem that the solvent used in the composition for forming the electron transport layer 34 dissolves and permeates into the hole transport layer 32 and the hole injection layer 31.

  In the present disclosure, the first organic layer covers the surface and the side surface of the first electrode layer on the first organic layer side, and the second organic layer is on the first electrode layer side of the second organic layer. A surface of the organic layer in contact with the surface on the second organic layer side and a side surface of the organic layer located on the first electrode layer side from the second organic layer among the plurality of organic layers are covered. Accordingly, when the organic layer is formed on the second electrode layer side of the second organic layer by a coating method, the solvent contained in the composition part for forming the organic layer is changed to the second organic layer. There exists an effect that it can suppress that it melt | dissolves and osmose | permeates from the side surface of the organic layer located in the 1 electrode layer side. Specifically, for example, as shown in FIG. 2, a case where the hole injection layer 31 is provided as the first organic layer and the light emitting layer 33 is provided as the second organic layer will be described. In this case, when the electron transport layer 34 is formed on the second electrode layer 4 side of the light emitting layer 33 that is the second organic layer by a coating method, the solvent contained in the composition for forming the electron transport layer 34 is: It is possible to suppress dissolution and permeation from the side surfaces of the hole transport layer 32 and the hole injection layer 31 located on the first electrode layer 2 side from the light emitting layer 33. In addition, about the code | symbol which is not demonstrated in FIG. 2, since it can be the same as that of FIG. 1 mentioned above, description is abbreviate | omitted.

  Hereinafter, the configuration and members of the organic EL element of the present disclosure will be described.

1. Configuration The organic EL element of the present disclosure has a configuration in which a substrate 1, a first electrode layer 2, an organic EL layer 3, and a second electrode layer 4 are laminated as shown in FIG. 1. In addition, the organic EL layer in the present disclosure includes a plurality of organic layers including a light emitting layer. In the organic EL element 10 shown in FIG. 1, the organic EL layer 3 includes a hole injection layer 31, a hole transport layer 2, a light emitting layer 33, and an electron transport layer 34.

  In the present disclosure, when the organic layer located closest to the first electrode layer among the plurality of organic layers is the first organic layer, the first organic layer is the first organic layer of the first electrode layer. Cover side and side surfaces.

  Here, the “organic layer located closest to the first electrode layer” is an organic EL layer that is disposed on the first electrode layer and is formed by laminating a plurality of organic layers. It means the organic layer that is the outer layer. Therefore, when an organic EL layer is disposed immediately above the first electrode layer, it means an organic layer in contact with the first electrode layer. For example, in FIGS. 1 and 2, the hole injection layer 31 corresponds to the first organic layer. In the present disclosure, by covering the first electrode layer with the first organic layer, it is possible to suppress the occurrence of defects such as a short circuit due to contact between the first electrode layer and the second electrode layer, Further, by covering the first electrode layer, it is possible to secure a wider light emitting region of the organic EL element. In addition, the “first organic layer covers the first organic layer side and side surfaces of the first electrode layer” means that the first organic layer covers all the exposed surfaces of the first electrode layer. It is preferable to coat.

  In the present disclosure, the second organic layer includes the second organic layer-side surface of the organic layer in contact with the surface of the second organic layer on the first electrode layer side, and the second organic layer among the plurality of organic layers. The side surface of the organic layer located on the first electrode layer side from the two organic layers is covered.

  Here, “the organic layer located on the first electrode layer side from the second organic layer among the plurality of organic layers” is arranged at a position closer to the first electrode layer side than the second organic layer. Means organic layer. For example, when the electron transport layer 34 is the second organic layer in FIG. 1, the hole injection layer 31, the hole transport layer 32, and the light emitting layer 33 are indicated. In FIG. 2, when the light emitting layer 33 is the second organic layer, the hole transport layer 32 and the hole injection layer 31 are indicated. Further, the “second organic layer includes the second organic layer side surface of the organic layer in contact with the first electrode layer side surface of the second organic layer, and the second organic layer of the plurality of organic layers. "The side of the organic layer positioned on the first electrode layer side from the layer" means that the second organic layer is exposed on all the surfaces of the organic layer positioned on the first electrode layer side of the second organic layer. Means coating. For example, as shown in FIG. 1, when each organic layer is formed so as to cover other organic layers located on the first electrode layer 2 side of the organic layer, the electron transport layer 34 is formed as the second organic layer. As a layer, the electron transport layer 34 covers the surface of the light emitting layer 33 located on the first electrode layer 2 side and the side surface of the light emitting layer 33. For example, as shown in FIG. 2, when the hole injection layer 31 is the first organic layer and the light emitting layer 33 is the second organic layer, the light emitting layer 33 is the hole injection layer 31. These side surfaces, the side surface of the hole transport layer 32, and the surface of the hole transport layer 32 on the side in contact with the light emitting layer are covered. In this way, the first second organic layer covers all the exposed surfaces in the organic layer located on the first electrode layer side of the second organic layer. Even if another organic layer is formed by a coating method, the solvent contained in the composition for forming the organic layer is dissolved from the side of the organic layer located on the first electrode layer side of the second organic layer. It becomes possible to suppress permeation.

  In the present disclosure, it is particularly preferable that the second organic layer is located on the second electrode layer side of the light emitting layer among the plurality of organic layers. Since the light emitting layer is covered with the second organic layer on the second organic layer side and side surfaces of the light emitting layer, another organic layer is formed on the second organic layer by a coating method. Even if it exists, it can suppress that the solvent contained in the composition for forming the said organic layer melt | dissolves and osmose | permeates from the side surface of a light emitting layer through a 2nd organic layer. Therefore, it is possible to suppress the effects of dissolution and permeation of the solvent into the light emitting layer, and to suppress the deterioration of the light emitting performance of the organic EL element and the life of the organic EL element. In addition, in the present disclosure, it is particularly preferable that all the organic layers are formed so as to cover the side surfaces of the organic layers located on the first electrode layer side as shown in FIG. Since dissolution and permeation by the solvent from the side surfaces of all the organic layers can be suppressed, the above-described operational effects of the present disclosure can be made remarkable.

  Furthermore, the second organic layer in the present disclosure may have an opening in the light emitting region of the organic EL element, and at least one organic layer of the plurality of organic layers may be disposed in the opening. . When the second organic layer has such a structure, the second organic layer is preferably a solvent permeation suppression unit having a function of suppressing dissolution and permeation by a solvent. Specifically, as shown in FIG. 3, the second organic layer has a solvent permeation suppression unit 51, and the organic layer is disposed in the opening R of the light emission region of the solvent permeation suppression unit 51. good. In the present disclosure, when the second organic layer is a solvent permeation suppression unit having an opening in the light emitting region, the organic layer disposed in the opening may be referred to as a functional unit 52 in some cases. Here, the “function of suppressing dissolution and penetration by a solvent” means dissolution in a solvent contained in a composition for forming an organic layer as a functional unit disposed in the opening of the second organic layer, It means a function that is difficult to penetrate. In the present disclosure, when the second organic layer is a solvent permeation suppression unit having a predetermined function, the other organic layer is formed on the second electrode side of the second organic layer by a coating method. It is possible to prevent the solvent contained in the composition for forming the organic layer from entering from the side surface of the organic layer disposed on the first electrode layer side of the second organic layer, and to form an organic EL element As a result, the function can be maintained without impairing the function. The function can be expressed by the remaining film ratio with respect to a predetermined solvent, and detailed description will be described in the section of “2. Member (1) Organic EL layer (a) Solvent permeation suppression unit” described later. .

  When the second organic layer is a solvent permeation suppression unit having an opening in the light emitting region and has a functional unit in the opening, examples of the solvent permeation suppression unit and the method of forming the functional unit include a solvent permeation suppression unit And forming an organic layer as a functional part in the opening formed in the light emitting region of the solvent permeation suppression part. In the present disclosure, to form the organic layer to be applied in the opening by forming the solvent permeation suppression unit so as to cover the side surface of the organic layer located on the first electrode layer side of the second organic layer It is possible to prevent the solvent in the composition from dissolving and permeating from the side surface of the organic layer located on the first electrode layer side of the second organic layer. In FIG. 3, the light emitting layer 33 has a second organic layer on the second electrode layer 4 side, and the second organic layer is a solvent permeation suppression unit having an opening, and a functional unit is provided in the opening. Although the example in which the electron transport layer 34 is disposed as described above has been described, such a solvent permeation suppression unit as the second organic layer is disposed on the second electrode layer side of the hole injection layer, for example, to suppress the solvent permeation. The hole transport layer may be formed in the opening formed in the part, or the light emitting layer is disposed in the opening formed in the solvent permeation suppressor disposed on the second electrode layer side of the hole transport layer. It may be formed and is not particularly limited. Moreover, since the reference numerals not described in FIG. 3 can be the same as those in FIG. 1 described above, description thereof is omitted here.

  In FIG. 1 and FIG. 3, the organic EL layer 3 has been described as an example composed of an organic layer of a hole injection layer 31, a hole transport layer 32, a light emitting layer 33, and an electron transport layer 34. There is no particular limitation as long as it is composed of a plurality of organic layers including a light emitting layer. Here, the “plurality of organic layers” means two or more organic layers including a light emitting layer, and the number of organic layers is preferably three or more. Since there are three or more organic layers, another organic layer can be applied and formed on the second organic layer, so that the second organic layer is on the first electrode layer side of the second organic layer. The effect of coating the positioned organic layer, that is, when the organic layer is formed on the second organic layer by a coating method, the solvent in the composition for forming the organic layer is the second organic layer. This is because the effect of suppressing dissolution and permeation from the side surface of the organic layer located on the first electrode layer side can be made remarkable.

  Furthermore, the organic EL element of the present disclosure may have a tandem structure in which the organic EL layer has a plurality of units. For example, as shown in FIG. 4, the organic EL layer 3 has a plurality of units composed of organic layers of a hole injection layer 31, a hole transport layer 32, a light emitting layer 33, and an electron transport layer 34. May be. In addition, in FIG. 4, the example which has two units shown with the code | symbol 3a, 3b is shown. In FIG. 4, the second organic layer is a solvent permeation suppression unit 51 having an opening, and the charge generation layer 36 is provided as the functional unit 52 in the opening of the light emitting region of the solvent permeation suppression unit 51. Show. Furthermore, FIG. 4 shows an example in which all the organic layers constituting the two units cover the organic layer located on the first electrode layer side. In the present disclosure, even in the case of an organic EL element having a tandem structure, a composition for forming the organic layer when the organic layer is formed on the second electrode layer side of the second organic layer by a coating method. The problem that the solvent in the substance dissolves and permeates from the side surface of the organic layer located on the first electrode layer side from the second organic layer can be solved.

2. Member The organic EL element of the present disclosure includes a base material, a first electrode layer on one surface of the base material, and a plurality of organic layers including a light emitting layer, and the first electrode layer is opposite to the base material. An organic EL layer on the surface, and a second electrode layer on the surface of the organic EL layer opposite to the first electrode layer.
Hereinafter, each member which the organic EL element of this indication has is explained.

(1) Organic EL Layer The organic EL layer in the present disclosure is a member that includes a plurality of organic layers including a light emitting layer and is disposed on the surface of the first electrode layer opposite to the base material.

  In the present disclosure, examples of the organic layer constituting the organic EL layer other than the light emitting layer include a hole injection layer, an electron injection layer, a hole transport layer, an electron transport layer, and a charge generation layer. The hole transport layer may be integrated with the hole injection layer by imparting a hole transport function to the hole injection layer. In addition, the electron transport layer may be integrated with the electron injection layer by adding an electron transport function to the electron injection layer. Furthermore, as an organic layer which comprises an organic EL layer, the layer etc. for preventing the penetration of a hole or an electron like a carrier block layer and improving recombination efficiency are mentioned.

  In the present disclosure, of the plurality of organic layers as described above, the organic layer on the first electrode side can be used as the first organic layer. The first organic layer is disposed so as to cover the first electrode layer. Moreover, in this indication, the organic layer located in the 2nd electrode layer side of a 1st organic layer can be used as a 2nd organic layer among the above several organic layers. The second organic layer includes a second organic layer-side surface of the organic layer that is in contact with the surface of the second organic layer on the first electrode layer side, and a second organic layer among the plurality of organic layers. The side surface of the organic layer located on the electrode layer side is covered.

  In the present disclosure, the second organic layer may have an opening in the light emitting region of the organic EL element, and at least one organic layer of the plurality of organic layers may be disposed in the opening. . Since the second organic layer has an opening in the light emitting region, a material having a predetermined resistance to a solvent can be used as the second organic layer. Therefore, while suppressing the increase in the light emitting function of the organic EL element and the thickness of the organic EL element, for example, when forming another organic layer on the second electrode layer side of the second organic layer by a coating method, the other There exists an effect that it can suppress that the solvent contained in the composition for forming this organic layer penetrate | invades from the side surface of the organic layer located in the 1st electrode layer side of a 2nd organic layer. That is, in the present disclosure, the second organic layer is a solvent permeation suppression unit having a function of suppressing dissolution and permeation by a solvent, and the organic layer is disposed as a functional unit in the opening. preferable. In addition, as the organic layer as the functional unit here, for example, the above-described organic layers such as a light emitting layer, a hole injection layer, an electron injection layer, a hole transport layer, an electron transport layer, and a charge generation layer are used. it can.

  Hereinafter, the solvent permeation suppression unit, the light emitting layer, the hole injection layer, the hole transport layer, the electron injection layer, and the electron transport layer constituting the organic EL layer in the present disclosure will be described.

(A) Solvent permeation suppression part The solvent permeation suppression part in this indication is used as the 2nd organic layer, and is a member which has an opening in a luminescence field. In addition, the organic layer which has a translucency of the grade which does not affect the light emission of an organic EL element is arrange | positioned as a function part in the opening part of a solvent penetration suppression part.

  The solvent permeation suppression unit in the present disclosure preferably has a predetermined resistance to the solvent contained in the composition for forming the organic layer as the functional unit. That is, in the composition for forming the organic layer serving as the functional unit by disposing the solvent permeation suppression unit so as to cover the side surface of the organic layer located on the first electrode layer side of the second organic layer. It is preferable that the solvent contained has such resistance that the solvent can be prevented from dissolving and penetrating from the side surface of the organic layer located on the first electrode layer side of the second organic layer. Therefore, the resistance of the solvent permeation suppression unit is a property with respect to the solvent contained in the composition for forming the organic layer as the functional unit, and the “solvent” here is a composition for forming the organic layer. Although it will not specifically limit if it is a solvent which can be used for, for example, water, glycerin, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, ethylene glycol, propylene glycol, Butanediol, ethylhexanol, benzyl alcohol, cyclohexanol, 12-amino-1-dodecanol, 2-methyl-2,4-pentanediol, diethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether, propylene glycol monomethyl ester Ter, propylene glycol monomethyl ether acetate, benzene, toluene, xylene, mesitylene, dodecylbenzene, cyclohexanone, tetralin, mesitylene, anisole, methylene chloride, tetrahydrofuran, dichloroethane, chlorobenzene, dichlorobenzene, chloroform, ethyl benzoate, butyl benzoate, acetonitrile , Ethyl acetate, propyl acetate, butyl acetate, propylene glycol 1-monomethyl ether 2-acetate. These may be used alone or in combination of two or more.

  The resistance of the solvent permeation suppression unit to the solvent varies depending on the type of the solvent, and can be indicated, for example, by the remaining film rate of the solvent permeation suppression unit when the solvent is brought into contact with the solvent permeation suppression unit. For example, the remaining film ratio of the solvent permeation suppression portion is preferably 50% or more, more preferably 60% or more, and particularly preferably 70% or more.

In addition, the remaining film rate of the solvent permeation suppression unit can be measured as follows. That is, first, a quartz substrate of 25 mm × 25 mm is prepared. Next, a solvent permeation suppression unit is formed on the quartz substrate. Next, when measuring the residual film ratio of the solvent permeation suppression unit, the solvent used in forming the layer to be in contact with the target solvent, that is, the solvent permeation suppression unit, is determined as the solvent permeation suppression unit. On the top, 1 mL for 25 mm × 25 mm is applied using a spin coater method. The number of rotations at this time can be appropriately adjusted according to the film thickness of the layer arranged so as to be in contact with the solvent permeation suppression unit. Thereafter, the solvent applied on the solvent permeation suppression unit is dried under the same conditions as when the layer is dried. In this way, a solvent permeation suppression unit coated with a solvent is created.
Here, the remaining film ratio of the solvent permeation suppression unit can be measured from the ratio of the absorbance (Abs) of the absorption maximum (λmax) of the solvent permeation suppression unit in the ultraviolet visible absorption spectrum using an ultraviolet-visible spectrophotometer. it can. Specifically, it can be calculated by the following formula.
([Absorbance of absorption maximum of solvent permeation suppression part after solvent application] / [absorbance of absorption maximum of solvent permeation suppression part before solvent application]) × 100 (%) = remaining film ratio (%)
If the solvent permeation suppression unit does not have absorption in the ultraviolet visible absorption spectrum, an atomic force microscope (AFM) or a stylus type surface shape measuring instrument (for example, DEKTAK series, manufactured by SLOANA) is used. Thus, the residual film ratio can be obtained by directly measuring the film thickness of the solvent permeation suppression part before and after the solvent application.

  The solvent permeation suppression unit has an opening in the light emitting region of the organic EL element. Therefore, the solvent permeation suppression unit may have transparency or may not have transparency. As a material of such a solvent permeation suppression portion, for example, a composite (PEDOT / PSS) composed of poly (3,4-ethylenedioxythiophene) called PEDOT and polystyrene sulfonic acid called PSS, poly (Ethyleneimine) derivatives, parylene and parylene derivatives, poly (4-vinylpyridine) derivatives, aromatic amine compounds such as N, N'-bis- (3-methylphenyl) -N, N'-bis- (phenyl ) -Benzidine (TPD), bis (N- (1-naphthyl-N-phenyl) benzidine) (α-NPD), 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (MTDATA) ), 4,4 ′, 4 ″ -tris (N- (2-naphthyl) -N-phenylamino) triphenylamine (2-TNATA) and the like. The solvent permeation suppression unit may further contain, in the molecule, an electron donating compound such as an anthracene derivative, carbazole derivative, thiophene derivative, fluorene derivative, distyrylbenzene derivative, or spiro compound.

  Moreover, as a material of the solvent permeation suppression part, for example, an amine polymer compound can be mentioned. Examples of the amine-based polymer compound include a polymer containing an aromatic amine derivative in a repeating unit. The polymer may be a copolymer further containing an electron-donating compound such as an anthracene derivative, carbazole derivative, thiophene derivative, fluorene derivative, distyrylbenzene derivative, and spiro compound in a repeating unit. The amine polymer compound may be, for example, a compound represented by the following general formula (1).

(In Formula (1), Ar ^{1 to} Ar ⁴ may be the same or different from each other, and are unsubstituted or substituted aromatic carbonized carbon atoms having 6 to 60 carbon atoms related to the conjugated bond. A hydrogen group or an unsubstituted or substituted heterocyclic group having 4 or more and 60 or less carbon atoms related to a conjugated bond, n is 1 or more and 10,000 or less, m is 0 or more and 10,000 or less, and n + m is 10 or more (The number of the repeating units is arbitrary.)

  The arrangement of the two repeating units is arbitrary, and may be, for example, a random copolymer, an alternating copolymer, a periodic copolymer, or a block copolymer. The average of n is preferably 5 or more and 5000 or less, and more preferably 10 or more and 3000 or less. Moreover, the average of m is preferably 5 or more and 5000 or less, and more preferably 10 or more and 3000 or less. The average n + m is preferably 10 or more and 10,000 or less, and more preferably 20 or more and 6000 or less.

In Ar ^{1 to} Ar ⁴ of the general formula (1), examples of the aromatic hydrocarbon in the aromatic hydrocarbon group include benzene, fluorene, naphthalene, anthracene, combinations thereof, and derivatives thereof, and phenylene. Examples include vinylene derivatives and styryl derivatives. Examples of the heterocyclic ring in the heterocyclic group include thiophene, pyridine, pyrrole, carbazole, combinations thereof, and derivatives thereof.

When Ar ^{1 to} Ar ^{4 in} the general formula (1) have a substituent, the substituent is preferably a linear or branched alkyl group or alkenyl group having 1 to 12 carbon atoms.

  Examples of the compound represented by the general formula (1) include poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (shown by the following formula (2) and referred to as FTB. 4,4 ′-(N- (4-sec-butylphenyl)) diphenylamine)], poly [(9,9-dioctylfluorenyl-2,7-diyl) -alt- represented by the following formula (3) co- (N, N′-bis {4-butylphenyl} -benzidine N, N ′-{1,4-diphenylene})] is a preferred compound.

  Examples of the material of the solvent permeation suppression unit in the present disclosure include a material containing at least one of the following (A) and (B) and an amine compound.

  (A) a compound represented by the following general formula (I);

(In General Formula (I), M is at least one of molybdenum, tungsten, and vanadium, and R ¹ and R ² may each independently have a substituent and include a hetero atom. And represents an aliphatic hydrocarbon group, an aromatic ring group, or a combination thereof, n represents a positive number of 1 or more and 3 or less, and m represents a positive number of 0 or more and 2 or less.

  (B) Transition metal-containing nanoparticles comprising at least one transition metal compound selected from the group consisting of transition metal oxides, transition metal carbide oxides, transition metal nitride oxides, and transition metal sulfide oxides, and a protective agent The transition metal is at least one of molybdenum, tungsten, and vanadium, and the transition metal-containing nanoparticles are formed by attaching a protective agent that protects the surface to the particle surface. A linking group capable of linking to a transition metal compound and an organic group having 1 or more carbon atoms, wherein the linking group includes a hydroxyl group, a sulfonamide group, and functional groups represented by the following general formulas (1a) to (1o) One or more transition metal compound nanoparticles selected from the group consisting of groups;

(In the formula, Z ¹ , Z ² and Z ³ each independently represent a halogen atom or an alkoxy group, and R represents a hydrogen atom or a methyl group.)

  The solvent permeation suppression unit in the present disclosure is a member having an opening in the light emitting region. In the opening formed in the solvent permeation suppression unit, for example, a light emitting layer, a hole injection layer, an electron injection layer, a hole transport layer, an electron transport layer, a charge generation layer, and the like are disposed as functional units. It is preferable to appropriately adjust the size and shape of the opening formed in the solvent permeation suppression unit according to the light emitting region of the organic EL element defined by the size and shape of the first electrode layer. Specifically, the size and shape of the opening formed in the solvent permeation suppression unit are preferably equal to or greater than the size and shape of the first electrode layer. Moreover, it is preferable that the position of the opening formed in the solvent permeation suppression unit overlaps with the light emitting region of the organic EL element defined by the first electrode layer in plan view. This is because a wider light-emitting region of the organic EL element can be secured.

  As described above, the thickness of the solvent permeation suppression portion is preferably a thickness that can impart predetermined resistance to the solvent. In addition, the thickness of the solvent permeation suppression portion can be made equal to the thickness of the organic layer serving as the functional portion formed in the opening. The thickness of such a solvent permeation suppression part can be, for example, in the range of 5 nm to 500 nm, and preferably in the range of 10 nm to 200 nm.

  As described above, the method for forming the solvent permeation suppression unit in the present disclosure can be arranged so as to cover the side surface of the organic layer, and can provide a predetermined opening in the light emitting region of the organic EL element. It is preferable that there is no particular limitation. For example, a method of forming an opening by forming a solvent permeation suppression portion on the entire surface so as to cover the first organic layer and then removing the solvent permeation suppression portion in the light emitting region of the organic EL element, or corresponding to the opening A method of forming the solvent permeation suppression portion through the mask, and a method of forming the solvent permeation control portion in a pattern using a coating method so that an opening is formed in the light emitting region of the organic EL element. Can be mentioned. Here, both the wet process and the dry process can be used to form the solvent permeation suppression unit. For example, vacuum deposition, printing, inkjet, die coating, spin coating, casting, dipping, bar coating, slit coating, blade coating, roll coating, gravure coating, screen printing, gravure Examples thereof include an offset printing method, a flexographic printing method, a spray coating method, a coating method such as a nozzle method, and a self-organizing method.

(B) Light-Emitting Layer Examples of materials used for the light-emitting layer in the present disclosure include light-emitting materials such as dye-based materials, metal complex-based materials, and polymer-based materials.

  Examples of dye-based materials include cyclopentadiene derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, pyridine Examples thereof include ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, oxadiazole dimers, and pyrazoline dimers.

  Examples of the metal complex-based material include aluminum quinolinol complex, benzoquinolinol beryllium complex, benzoxazole zinc complex, benzothiazole zinc complex, azomethyl zinc complex, porphyrin zinc complex, and eurobium complex. Or a metal complex having a rare earth metal such as Tb, Eu, or Dy and having a oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structure, or the like as a ligand.

  Furthermore, examples of the polymer material include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyvinylcarbazole, polyfluorene derivatives, polyquinoxaline derivatives, and copolymers thereof. Is mentioned.

  The light emitting layer in the present disclosure may contain a doping agent for the purpose of improving the light emission efficiency and changing the light emission wavelength. Examples of the doping agent include perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squalium derivatives, porphyrin derivatives, styryl dyes, tetracene derivatives, pyrazoline derivatives, decacyclene, phenoxazone, quinoxaline derivatives, carbazole derivatives, fluorene derivatives, and the like. It is done.

  The thickness of the light emitting layer in the present disclosure is not particularly limited as long as it can provide a function of emitting light by providing a recombination field between electrons and holes, and is, for example, 1 nm or more. Moreover, it can be 500 nm or less.

  The light emitting layer in the present disclosure may be formed in a pattern so as to have light emitting portions of a plurality of colors such as red, green, and blue. Thereby, an organic EL element capable of color display can be obtained.

  As a method for forming a light emitting layer in the present disclosure, a general method for forming a light emitting layer can be adopted, and either a wet process or a dry process can be used. For example, vacuum deposition, printing, inkjet, die coating, spin coating, casting, dipping, bar coating, slit coating, blade coating, roll coating, gravure coating, gravure offset printing, Examples thereof include a coating method such as a flexographic printing method and a spray coating method, and a self-organizing method. In the present disclosure, the light emitting layer is preferably formed by a coating method. This is because the effects of the present disclosure can be made remarkable when light emission unevenness due to coating unevenness occurs.

(C) Hole injection layer and hole transport layer In the present disclosure, the hole transport layer may be integrated with the hole injection layer by imparting a hole transport function to the hole injection layer. . That is, the hole injection layer may have only a hole injection function, or may have both a hole injection function and a hole transport function.

  The material used for the hole injection layer is not particularly limited as long as the material can stabilize the injection of holes into the light emitting layer. In addition, phenylamine, starburst amine, phthalocyanine, vanadium oxide, molybdenum oxide, ruthenium oxide, aluminum oxide, titanium oxide and other oxides, amorphous carbon, polyaniline, polythiophene, polyphenylene vinylene derivatives, etc. can be used. . Specifically, bis (N-((1-naphthyl) -N-phenyl) benzidine (α-NPD), 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (m- MTDATA), poly (3,4-ethylenedioxythiophene) -polystyrene sulfonic acid (PEDOT-PSS), polyvinylcarbazole (PVCz) and the like.

  Further, the thickness of the hole injection layer is not particularly limited as long as the hole injection function and the hole transport function are sufficiently exhibited, but specifically, it is preferably 0.5 nm or more, It is preferable that it is 10 nm or more. In addition, the thickness of the hole injection layer is preferably 500 nm or less, and more preferably 200 nm or less.

  Since the method for forming the hole injection layer can be the same as the method for forming the light emitting layer described above, description thereof is omitted here.

(D) Electron Injection Layer and Electron Transport Layer In the present disclosure, the electron transport layer may be integrated with the electron injection layer by imparting an electron transport function to the electron injection layer. That is, the electron injection layer may have only an electron injection function, or may have both an electron injection function and an electron transport function.

  The material used for the electron injection layer is not particularly limited as long as the material can stabilize the injection of electrons into the light emitting layer. In addition to the compounds exemplified as the light emitting material of the light emitting layer, Aluminum lithium alloy, lithium fluoride, sodium fluoride, strontium, magnesium oxide, magnesium fluoride, strontium fluoride, calcium fluoride, barium fluoride, aluminum oxide, strontium oxide, calcium, polymethyl methacrylate, sodium polystyrene sulfonate, Examples include lithium, cesium, cesium fluoride, alkali metals, alkali metal halides, alkali metal organic complexes, and the like.

  Alternatively, a metal doped layer in which an alkali metal or alkaline earth metal is doped on an electron transporting organic material may be formed and used as an electron injection layer. Examples of the electron-transporting organic material include bathocuproin, bathophenanthroline, and phenanthroline derivatives. Examples of the metal to be doped include Li, Cs, Ba, and Sr. In addition, other examples include 8-hydroxyquinolinolato-lithium called Liq.

  The thickness of the electron transport layer is not particularly limited as long as the electron transport function is sufficiently exerted.

  Since the formation method of an electron carrying layer can be made the same as the formation method of the light emitting layer mentioned above, description here is abbreviate | omitted.

(2) 1st electrode layer The 1st electrode layer in this indication is a member arranged on one side of the substrate mentioned below. The organic EL element of the present disclosure may extract light from the first electrode layer side or may extract light from the second electrode layer side. When the organic EL element of the present disclosure extracts light from the first electrode layer side, the first electrode layer preferably has a predetermined transparency.

  When the 1st electrode layer in this indication has predetermined transparency, the transparency which the 1st electrode layer has is the transparency which can permeate the luminescence from an organic EL layer, and can display. For example, the transmittance in the visible light region is preferably 80% or more, and more preferably 90% or more.

  The first electrode layer may be an anode or a cathode. As a material of the first electrode layer, a material used for a general organic EL element can be used. When the first electrode layer is an anode, it is preferable that the resistance is small, and generally a metal material that is a conductive material is used, but an organic compound or an inorganic compound may be used. For the anode, a conductive material having a large work function is preferably used so that holes can be easily injected. For example, metals such as Au, Cr, and Mo; indium tin oxide called ITO, indium oxide such as indium zinc oxide, zinc oxide, and indium oxide called IZO; high conductivity such as metal-doped polythiophene Molecule and the like. These conductive materials may be used alone or in combination of two or more. When two or more types are used, layers made of each material may be stacked.

  For the cathode, it is preferable to use a conductive material having a low work function so that electrons can be easily injected. Examples thereof include magnesium alloys such as MgAg, aluminum alloys such as AlLi, AlCa, and AlMg, and alloys of alkali metals and alkaline earth metals such as Li, Cs, Ba, Sr, and Ca.

  The thickness of the first electrode layer can be adjusted as appropriate according to the application of the organic EL element and the like, and is not particularly limited.

  The formation method of the first electrode layer can be appropriately selected according to the configuration of the organic EL element. The first electrode layer may be formed on the entire surface of the base material, and the first electrode layer is formed in a pattern. May be. Since the specific formation method of the first electrode layer can be the same as the general electrode formation method, description thereof is omitted here.

(3) Second electrode layer The second electrode layer in the present disclosure is a member disposed on the surface of the organic EL layer opposite to the first electrode layer.
The second electrode layer can be the same as the contents described in the above section “(2) First electrode layer”, and thus description thereof is omitted here.

(4) Base material The base material in this indication is a member which supports the 1st electrode layer, organic EL layer, and 2nd electrode layer which were mentioned above.

  The base material in the present disclosure may or may not have transparency, but when taking out light from the first electrode layer side, the base material preferably has transparency.

  When the substrate in the present disclosure has a predetermined transparency, the transparency of the substrate is preferably transparent enough to transmit light emitted from the organic EL layer, for example, The transmittance in the visible light region is preferably 80% or more, and more preferably 90% or more. Here, the transmittance | permeability of a base material can be measured with the test method of the total light transmittance of the plastic-transparent material according to JISK7361-1.

  The base material in the present disclosure may or may not have flexibility, and can be appropriately selected according to the use of the organic EL element, but it has flexibility in particular. Is preferred. This is because flexibility can be imparted to the organic EL element of the present disclosure.

  Examples of the base material include inflexible rigid materials such as quartz glass, Pyrex (registered trademark) glass, and synthetic quartz plate, or flexibility such as resin film, optical resin plate, and thin glass. Examples thereof include flexible materials. In addition, the base material in this indication may be the laminated body in which the barrier layer was formed in the resin film.

  The thickness of the base material can be appropriately selected according to the type of material used for the base material, the use of the organic EL element, and the like, for example, 0.005 mm or more, and 5 mm or less. can do.

(5) Other members The organic EL element of this indication should just have each member mentioned above, and may have other members if needed. About another member, the member used for a general organic EL element is employable. For example, a sealing member that can be disposed so as to cover the organic EL element and prevent intrusion of moisture, a counter substrate that is disposed on the surface of the second electrode layer opposite to the organic EL layer, and the like Can be mentioned.

(A) Sealing member The sealing member in this indication is a member arranged so that an organic EL element may be covered.

  Examples of the material of the sealing member in the present disclosure include radical seal materials using resins such as various acrylates such as ester acrylate, urethane acrylate, epoxy acrylate, melamine acrylate, and acrylic resin acrylate, and urethane polyester, epoxy, and vinyl ether. Examples thereof include photo-curing resins such as cation-based sealing materials using resins such as thiol-ene addition-type resin-based sealing materials, and thermosetting resins.

  About the thickness of the sealing member, it can adjust suitably according to the use etc. of the organic EL element of this indication, and is not specifically limited.

  As a method for forming the sealing member, a conventional method can be used. For example, inkjet method, dispenser method, spin coating method, die coating method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, flexographic printing method, offset printing method, and Screen printing method etc. are mentioned.

(B) Opposite base material The counter base material in the present disclosure is a member disposed on the surface of the second electrode layer opposite to the organic EL layer.

  Since the opposing base material in this indication is a member arrange | positioned on the surface on the opposite side to the light emission surface of an organic EL element, it may have transparency and does not need to have transparency.

  Examples of the material of the counter substrate in the present disclosure include inflexible rigid materials such as quartz glass, Pyrex (registered trademark) glass, and synthetic quartz plate, or resin films, optical resin plates, thin glass, and the like. Examples thereof include a flexible material having flexibility. In addition, the opposing base material in this indication may be the laminated body in which the barrier layer was formed in the resin film.

3. Manufacturing method of organic EL element The manufacturing method of the organic EL element of this indication will not be specifically limited if it is a method which can obtain the organic EL element mentioned above. In the present disclosure, an organic EL element can be obtained by the following method. That is, the substrate includes a substrate, a first electrode layer on one surface of the substrate, and a plurality of organic layers including a light emitting layer, and the organic on the surface of the first electrode layer opposite to the substrate. An organic EL element manufacturing method comprising: an EL layer; and a second electrode layer on a surface opposite to the first electrode layer of the organic EL layer, wherein the most of the plurality of organic layers When the organic layer located on the first electrode layer side is the first organic layer, the first organic layer covers the first electrode layer side surface and the side surface of the first electrode layer. A first organic layer forming step to be formed on the first organic layer, and among the plurality of organic layers, any one of the organic layers located on the second electrode layer side of the first organic layer is defined as a second organic layer. The second organic layer is formed on the second organic layer side surface of the organic layer in contact with the first electrode layer side surface of the second organic layer, and A second organic layer forming step of forming a second organic layer so as to cover a side surface of the organic layer located on the first electrode layer side from the second organic layer of the plurality of organic layers. With this manufacturing method, a predetermined organic EL element can be obtained.

  In the present disclosure, the first organic layer forming step is preferably a step of forming the first organic layer by a coating method. Moreover, it is preferable that a 2nd organic layer formation process is a process of forming a 2nd organic layer by the apply | coating method. Further, in the present disclosure, when the organic EL layer in the organic EL element has another organic layer other than the first organic layer and the second organic layer, the step of forming the other organic layer is also applied. The method is preferably used. This is because the effect of the present disclosure such that the solvent contained in the composition for forming the organic layer is prevented from dissolving and penetrating into other organic layers can be made remarkable.

  About the formation method of each member which comprises the organic EL element of this indication, since it can be made to be the same as that of the content demonstrated by the term of each member mentioned above, description here is abbreviate | omitted.

4). Application The application of the organic EL element of the present disclosure is not particularly limited, and can be applied to, for example, a display device, a lighting device, a light source, and the like. In the present disclosure, it is preferable to form a plurality of organic layers constituting the organic EL layer by using a coating method, and from such a viewpoint, it is preferable to apply to an illumination device.

Hereinafter, the present disclosure will be specifically described using examples and comparative examples.
In the following examples and comparative examples, the work was performed in a glove box under an atmosphere of nitrogen (oxygen concentration 1 ppm or less, moisture concentration 1 ppm or less) unless otherwise specified.

[Example 1]
In Example 1, an organic EL element 10 similar to that shown in FIG. 1 was formed except that a hole injection / transport layer was used instead of the hole transport layer and an electron injection / transport layer was used instead of the electron transport layer. .

<Base material preparation process>
As a base material, a 25 mm × 25 mm × 0.7 mm glass substrate (manufactured by Sanyo Vacuum Co., Ltd.) was prepared.

<First electrode layer forming step>
Next, as a first electrode layer (anode), ITO having a thickness of 150 nm was formed in a stripe pattern on one surface of the base material, and this was used as an ITO substrate. Next, the obtained ITO substrate was subjected to ultrasonic cleaning in the order of neutral detergent and ultrapure water, and then UV ozone cleaning was performed for 10 minutes.

<Hole injection layer forming step>
Next, a hole injection layer was formed on the surface of the ITO substrate on the first electrode layer side so as to cover the surface and side surfaces of the first electrode layer. As the hole injection layer, a 30 nm thick PEDOT-PSS thin film was formed in the atmosphere. The PEDOT-PSS thin film is coated with a PEDOT-PSS solution (Bayer, Baytron P AI 4083), and then heated at 200 ° C. in the air using a hot plate to evaporate the solvent. The film was formed by drying for 30 minutes.

<Hole injection transport layer formation process>
Next, in the glove box, a hole injection transport layer was formed on the surface of the hole injection layer opposite to the first electrode layer so as to cover the surface and side surfaces of the hole injection layer. As the hole injecting and transporting layer, poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (4,4 ′-(N— (4-sec-butylphenyl)) diphenylamine)] (TFB) thin film was formed. The TFB thin film was coated with a solution prepared by dissolving TFB at a concentration of 1.0% by weight in xylene by a spin coating method, and then a hot plate was used to evaporate the solvent. A film was formed by drying for 30 minutes under a temperature condition of ° C.

<Light emitting layer forming step>
Next, a light emitting layer was formed on the surface of the hole injection transport layer opposite to the hole injection layer so as to cover the surface and side surfaces of the hole injection transport layer. The light-emitting layer contains Tris [2- (p-tolyl) pyridine] iridium (III) (Ir (mppy) 3) having a thickness of 80 nm as a light-emitting dopant, and Poly (N-vinylcarbazole) (PVK) and 1 , 3-bis [(4-tert-butylphenyl) -1,3,4-oxydiazolyl] phenylene (OXD-7) as a host was formed. The mixed thin film was applied with a solution obtained by dissolving Ir (mppy) 3, PVK, and OXD-7 in toluene at a concentration of 1.8% by weight by spin coating, and then hot to evaporate the solvent. A plate was used to form a film by drying at 110 ° C. for 30 minutes. Moreover, solid content in the said solution was adjusted to PVK: OXD-7: Ir (mppy) 3 = 70: 20: 10 by weight ratio.

<Electron injection transport layer formation process>
Next, an electron injecting and transporting layer was formed on the surface of the light emitting layer opposite to the hole injecting and transporting layer so as to cover the surface and side surfaces of the light emitting layer. As the electron injecting and transporting layer, a LiBq thin film having a thickness of 5 nm or less was formed. The LiBq thin film was prepared by applying a solution obtained by dissolving LiBq represented by the following formula in 1-butanol at a concentration of 0.2 wt% by a spin coating method, and then using a hot plate to evaporate the solvent. The film was formed by drying for 15 minutes under a temperature condition of 110 ° C.

<Second electrode layer forming step>
Next, Al having a thickness of 100 nm was formed as a second electrode layer (cathode) on the surface of the electron injecting and transporting layer opposite to the light emitting layer. In addition, Al was formed into a film by the resistance heating vapor deposition method in the vacuum (1 * 10 <^-4> Pa).

<Sealing process>
Finally, sealing was performed using a non-alkali glass and a UV curable epoxy adhesive in a glove box to obtain an organic EL element of the present disclosure.

[Example 2]
In Example 2, an organic EL element 10 similar to that in FIG. 3 was formed except that a hole injection / transport layer was used instead of the hole transport layer and an electron injection / transport layer was used instead of the electron transport layer.

<Base material preparation step, first electrode layer formation step, hole injection layer formation step, hole injection transport layer formation step, light emitting layer formation step>
In the same manner as in Example 1 described above, a substrate, a first electrode layer, a hole injection layer, a hole injection transport layer, and a light emitting layer were formed.

<Solvent penetration control part formation process>
The side of the light emitting layer opposite to the hole injecting and transporting layer was covered with the side surface of the light emitting layer and masked to have an opening as shown in FIG. 3 to form a solvent permeation suppression portion. A PEDOT-PSS thin film having a thickness of 30 nm was formed as the solvent permeation suppression unit. The PEDOT-PSS thin film is coated with a PEDOT-PSS solution (Bayer, Baytron P AI 4083), and then dried for 30 minutes at 120 ° C. using a hot plate to evaporate the solvent. To form a film.

<Electron injection transport layer formation process>
Next, an electron injecting and transporting layer was formed in the opening provided in the solvent permeation suppression unit. The material and method for forming the electron injecting and transporting layer are the same as in Example 1.

<Sealing process>
Finally, sealing was performed using a non-alkali glass and a UV curable epoxy adhesive in a glove box to obtain an organic EL element of the present disclosure.

[Comparative example]
An organic EL element was obtained in the same manner as in Example 1 except that each layer was formed to have the structure shown in FIG.

[Evaluation]
A voltage was applied between the first electrode layer and the second electrode layer to the organic EL elements obtained in Examples 1 and 2 and the comparative example, and current efficiency at 10 mA / cm ² was measured. Further, the current was set so that the luminance was 1000 cd / m ^2, and the time (luminance half-life) during which the luminance decreased to 500 cd / m ² when the constant current was continuously applied was measured. Table 1 shows the relative ratio when the current efficiency and the luminance half-life of the comparative example are each 100.

  As shown in Table 1, the organic EL elements of Example 1 and Example 2 having the configuration of the present disclosure were able to improve the life compared to the comparative example. This is because when the organic EL element of Example 1 and Example 2 has a predetermined configuration, the solvent contained in the composition for forming an organic layer is different from that of the organic layer forming composition when the organic layer is formed using a coating method. It can be considered that dissolution and permeation from the side surface of the organic layer can be suppressed, and that the residual solvent in each organic layer can be reduced and the deterioration of the organic layer due to solvent permeation can be reduced. Moreover, in Example 2 which has a solvent penetration suppression part, it has confirmed that the effect became remarkable.

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... 1st electrode layer 3 ... Organic EL layer 4 ... 2nd electrode layer 10 ... Organic EL element

Claims (5)

A substrate, a first electrode layer on one surface of the substrate, and a plurality of organic layers including a light-emitting layer, the organic electroluminescence on the surface of the first electrode layer opposite to the substrate An organic electroluminescent element comprising: a layer; and a second electrode layer on a surface of the organic electroluminescent layer opposite to the first electrode layer,
When the organic layer located closest to the first electrode layer among the plurality of organic layers is a first organic layer, the first organic layer is the first organic layer of the first electrode layer. Covering the layer side and side,
Of the plurality of organic layers, when any one of the organic layers located on the second electrode layer side of the first organic layer is a second organic layer, the second organic layer is A surface of the organic layer in contact with the surface on the first electrode layer side of the second organic layer, and a surface of the second organic layer side of the plurality of organic layers from the second organic layer to the first electrode layer side The organic electroluminescent element which coat | covers the side surface of the organic layer located in this.   2. The organic electroluminescence element according to claim 1, wherein the second organic layer is located closer to the second electrode layer than the light emitting layer among the plurality of organic layers.   The second organic layer has an opening in a light emitting region of the organic electroluminescence element, and at least one organic layer of the plurality of organic layers is disposed in the opening. Item 3. The organic electroluminescence device according to Item 1 or 2.   The organic electroluminescence according to claim 3, wherein the second organic layer has a remaining film ratio of 50% or more with respect to a solvent contained in a composition for forming the organic layer disposed in the opening. element.   The organic electroluminescent element according to any one of claims 1 to 4, wherein the plurality of organic layers are of a coating type.