JP7038049B2 - Organic electroluminescence device and method for manufacturing organic electroluminescence device - Google Patents

Description

The present invention relates to an organic electroluminescence device and a method for manufacturing an organic electroluminescence device.

In an organic electroluminescence element (organic EL element), improvement in luminous efficiency is required. In response to this demand, in order to take out the light emitted from the light emitting layer of the organic EL element to the outside of the organic EL element, a configuration including an optical member composed of an uneven layer having an uneven shape formed on the surface has been proposed. For example, see Patent Document 1, Patent Document 2, and Patent Document 3).
Further, as an internal light extraction technique, a configuration in which a layer containing scattered fine particles is provided on a substrate has been proposed (see, for example, Patent Document 4).

Japanese Unexamined Patent Publication No. 2013-109932. Japanese Unexamined Patent Publication No. 2013-157340 Japanese Unexamined Patent Publication No. 11-283751 International Publication No. 2015/0836660

However, in the organic EL element in which the uneven layer is provided to improve the luminous efficiency, the emission brightness is lowered and dark spots are generated due to the outgas generated from the uneven layer and the adsorption of water by the uneven layer. Therefore, having the uneven layer reduces the reliability of the organic EL element. Further, even when a layer containing scattered fine particles is used, the range of material selection is narrowed due to the relationship between the refractive index of the organic EL element and the substrate, and the configuration that sufficiently satisfies the reliability of the organic EL element is still available. Not found.

In order to solve the above-mentioned problems, the present invention provides an organic electroluminescence device capable of improving luminous efficiency and reliability.

The organic electroluminescence element of the present invention has a base material, an uneven layer having an uneven structure on the surface and an average thickness of 100 nm or more and 2500 nm or less, a barrier layer formed on the uneven layer, and a barrier layer. It includes a first electrode provided, a light emitting unit provided on the first electrode, and a second electrode provided on the light emitting unit. The height of the convex portion of the concave-convex layer is 10 nm or more and 1000 nm or less, the thickness of the concave portion of the concave-convex layer is 10 nm or more and 2000 nm or less, and the surface of the barrier layer and the surface of the second electrode are uneven. It has a shape that follows the structure.
Further, in the method for manufacturing an organic electroluminescence element of the present invention, a step of forming a coating film containing a material for forming an uneven layer on a substrate and an uneven structure of a mother mold transferred to the coating film, the average thickness is 100 nm or more. A step of forming an uneven layer having a convex portion of 2500 nm or less , a convex portion height of 10 nm or more and 1000 nm or less, and a concave portion having a thickness of 10 nm or more and 2000 nm or less, a step of forming a barrier layer on the uneven layer, and a barrier. It has a step of forming a first electrode on a layer, a step of forming a light emitting unit on the first electrode, and a step of forming a second electrode on the light emitting unit, from the barrier layer to the second electrode. Is formed into a shape that follows the uneven structure of the uneven layer.

According to the present invention, it is possible to provide an organic electroluminescence device capable of improving luminous efficiency and reliability.

It is a figure which shows the schematic structure of the organic EL element. It is a process drawing for forming an uneven layer. It is a process drawing for forming an uneven layer. It is a process drawing for forming an uneven layer.

Hereinafter, examples of embodiments for carrying out the present invention will be described, but the present invention is not limited to the following examples.
The explanation will be given in the following order.
1. 1. Embodiment of organic electroluminescence device 2. Manufacturing method of organic electroluminescence device

<1. Embodiment of organic electroluminescence device>
Hereinafter, specific embodiments of the organic electroluminescence device (organic EL device) will be described.

FIG. 1 shows a schematic configuration diagram (cross-sectional view) of the organic EL element. The organic EL element 10 shown in FIG. 1 has a base layer 12, an uneven layer 13 having an uneven structure on the surface, a barrier layer 14, a first electrode 15, a light emitting unit 16, a second electrode 17, and an adhesive layer on a base material 11. It has 18 and a sealing base material 19. The organic EL element 10 shown in FIG. 1 is a bottom emission type element that extracts the light emitted from the light emitting unit 16 from the base material 11 side.

In the organic EL element 10, the uneven layer 13 is formed so as to be in direct contact with the base layer 12. The barrier layer 14 formed on the uneven layer 13 has an uneven structure similar to that of the uneven layer 13 formed on the surface of the layer so as to follow the uneven structure formed on the surface of the uneven layer 13. Similarly, the first electrode 15, the light emitting unit 16, and the second electrode 17 formed on the barrier layer 14 have irregularities on the surface of each layer so as to follow the irregular shape formed on the surface of the concave-convex layer 13. A concave-convex shape similar to that of the layer 13 is formed. Further, the pressure-sensitive adhesive layer 18 has a concavo-convex shape similar to that of the concavo-convex layer 13 formed on the surface on the side of the second electrode 17, and the surface on the opposite side to the second electrode 17 is flattened. Then, the sealing base material 19 is bonded to the flat surface on the pressure-sensitive adhesive layer 18.

In the organic EL element 10, the uneven layer 13 has an average thickness of 100 nm or more and 2500 nm or less. Here, the height of the convex portion of the concave-convex layer 13, the thickness of the convex portion, the thickness of the concave portion, and the average thickness of the concave-convex layer 13 will be described with reference to FIG. As shown in FIG. 1, in the concave-convex layer 13, the thickness from the bottom surface to the highest position of the convex portion of the concave-convex structure is the thickness C in the convex portion of the concave-convex layer 13. Further, the thickness from the bottom surface of the concave-convex layer 13 to the lowest position of the concave portion is the thickness B in the concave portion of the concave-convex layer 13. Further, the difference between the thickness C in the convex portion and the thickness B in the concave portion of the concave-convex layer 13 is the height A of the convex portion. Further, the average thickness of the uneven layer 13 is an average value of the thickness B in the concave portion and the thickness C in the convex portion.

Further, in the organic EL element 10, the barrier layer 14, the first electrode 15, the light emitting unit 16, and the second electrode 17 are formed in a shape that follows the uneven shape formed on the surface of the concave-convex structure of the concave-convex layer 13. ing. Here, the shape to follow is the convexity of the uneven shape of the surface (hereinafter, the surface) on the sealing base material 19 side in each layer of the barrier layer 14, the first electrode 15, the light emitting unit 16, and the second electrode 17. It means that the height of the portion is within ± 20% of the height A of the convex portion of the uneven layer 13. That is, it means that the height E of the convex portion in the concave-convex shape of the surface of the second electrode 17 on the sealing base material 19 side is within ± 20% of the height A of the convex portion in the concave-convex layer 13. As a result, not only the light in the substrate mode but also the light in the waveguide mode can be taken out, and the luminous efficiency of the organic EL element is improved.

Further, the height D of the convex portion in the uneven shape of the surface of the barrier layer 14 shown in FIG. 1 is within ± 20% of the height A of the convex portion in the concave-convex layer 13. Similarly, the height of the convex portion on the surface of each layer formed between the barrier layer 14 and the second electrode 17 is within ± 20% of the height A of the convex portion in the concave-convex layer 13. Further, the height D of the convex portion in the uneven shape of the surface of the barrier layer 14 is preferably within ± 10% of the height A of the convex portion in the uneven layer 13.

In the organic EL element 10, the height A of the convex portion of the uneven layer 13 is preferably 10 nm or more and 1000 nm or less. Further, it is preferable that the pitch of the convex portion of the concave-convex layer 13 is 100 nm or more and 2000 nm or less. Further, it is preferable that the height of the convex portion on the surface of each layer from the barrier layer 14 to the second electrode 17 is within ± 20% of the height D of the convex portion of the barrier layer 14. It is preferable that the pitch of the convex portions on the surface of each layer from the barrier layer 14 to the second electrode 17 is within ± 20% of the pitch of the convex portions of the barrier layer 14.

If the uneven shape of the uneven layer 13 can be maintained from the barrier layer 14 to the second electrode 17, scattering at the interface between the second electrode 17 and the other layer is promoted, and light in the waveguide mode can be taken out. .. On the other hand, when the uneven shape of the uneven layer 13 exceeds the above range, and particularly when the uneven shape becomes larger than the wavelength of the emitted light, only the light in the substrate mode can be extracted. Therefore, since the concave-convex layer 13 to the second electrode 17 of the organic EL element 10 have the above-mentioned shape, the luminous efficiency of the organic EL element 10 is improved.

In the concave-convex layer 13, the thickness, the height A of the convex portion, the thickness B in the concave portion, and the thickness C in the convex portion can be obtained by observing the cross section of the concave-convex layer 13 in the organic EL element 10. Specifically, the uneven layer 13 is cut at an arbitrary position in the thickness direction using a cross section polisher, a fine cutter, a FIB (Focused Ion Beam), or the like. Next, the cross-sectional profile of the uneven layer 13 is photographed using an SEM (Scanning Electron Microscope) or a TEM (Transmission Electron Microscope). After shooting, the height A of the convex portion at an arbitrary position, the thickness B of the concave portion, and the thickness C of the convex portion are measured at 100 points or more, and the height A, the thickness B, and the thickness C are measured from the average value. Is required. Further, the average thickness of the uneven layer 13 can be obtained from the average value of the thickness B in the concave portion and the thickness C in the convex portion.
Further, the thickness of the barrier layer 14, the first electrode 15, the light emitting unit 16, and the second electrode 17, and the height of the convex portion on the surface are also 100, as in the case of the uneven layer 13 described above, by observing the cross section. It is obtained from the average value of the values measured above the point.

The pitch of the convex portions means an average value when the distance between adjacent convex portions on the surface of the concave-convex layer 13 is measured. Further, for the pitch of such convex portions, surface irregularities are analyzed using a scanning probe microscope (for example, product name "E-sweep" manufactured by SII Nanotechnology Co., Ltd.) under the above analysis conditions. After measuring the unevenness analysis image, it is a value that can be calculated by measuring 100 points or more of the distances between arbitrary adjacent convex portions or adjacent concave portions in the unevenness analysis image and calculating the average thereof.

Further, the organic EL element 10 has a barrier layer 14 on the uneven layer 13. That is, the barrier layer 14 is interposed between the uneven layer 13 and the light emitting unit 16. Therefore, the outgas generated from the uneven layer 13 can be blocked by the barrier layer 14, and the adverse effect of the outgas from the uneven layer 13 on the light emitting unit 16 can be suppressed. Further, since the barrier layer 14 can block the moisture adsorbed by the uneven layer 13, it is possible to suppress the adverse effect of the moisture on the light emitting unit 16. Therefore, by having the barrier layer 14 between the uneven layer 13 and the light emitting unit 16, the reliability of the organic EL element 10 is improved.
The barrier layer 14 is formed directly above the uneven layer 13, and is formed so that the uneven layer 13 and the barrier layer 14 are in direct contact with each other. Although another layer may be provided between the uneven layer 13 and the barrier layer 14, this layer is also formed in a shape that follows the uneven structure of the uneven layer 13.

Hereinafter, each configuration of the organic EL element 10 will be described. The following description is an example of configuring the organic EL element of the embodiment, and other configurations can be applied as long as the action and effect of the organic EL element can be obtained.

Further, the organic EL element 10 shown in FIG. 1 is a bottom emission type element that extracts the light emitted from the light emitting unit 16 from the base material 11 side. Therefore, the first electrode 15, the uneven layer 13, the base layer 12, and the base material 11 are made of a transparent material, and the second electrode 17 is made of a conductive layer made of a metal film having high reflectance or the like. Further, as the organic EL element, in addition to the bottom emission type organic EL element, a top emission type organic EL element or a double-sided light emitting type organic EL element can also be used. In the case of the top emission type organic EL element, in the organic EL element 10 shown in FIG. 1, the sealing base material 19, the pressure-sensitive adhesive layer 18, and the second electrode 17 are made of a transparent material, and the first electrode 15 is formed. Is composed of a conductive layer made of a metal film or the like having a high reflectance. Further, in the case of a double-sided light emitting type organic EL element, each layer is composed of a transparent material.

Even when the organic EL element 10 is a top emission type, each layer from the barrier layer 14 to the second electrode 17 is formed in a shape that follows the uneven shape formed on the surface of the uneven layer 13, and thus is sealed. The efficiency of extracting light extracted from the base material 19 side is also improved. Similarly, even if the organic EL element 10 is a double-sided light emitting type, the light extraction efficiency is improved. Therefore, even in the top emission type organic EL element 10 and the double-sided light emitting type organic EL element 10, the luminous efficiency is improved by having the uneven layer 13.

[Base material]
Examples of the substrate material constituting the substrate 11 include glass, quartz, and a resin substrate. A particularly preferable base material 11 is a resin substrate capable of imparting flexibility to the organic EL element 10. The resin substrate may have a structure having a barrier layer, if necessary.

The resin that can be used as the base material 11 is not particularly limited, and for example, polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and modified polyester, polyethylene (PE) resin, polypropylene (PP) resin, and polystyrene resin. , Polyolefin resins such as cyclic olefin resins, vinyl resins such as polyvinyl chloride and polyvinylidene chloride, polyether ether ketone (PEEK) resins, polysulfone (PSF) resins, polyether sulfone (PES) resins, polycarbonates ( PC) resin, polyamide resin, polyimide resin, acrylic resin, triacetyl cellulose (TAC) resin and the like can be mentioned. These resins may be used alone or in combination of two or more. Further, the base material 11 may be an unstretched film or a stretched film.

It is preferable that the base material 11 has high transparency because the efficiency of light extraction from the organic EL element 10 side is likely to be improved. Transparency means that the total light transmittance in the visible light wavelength region measured by a method based on JIS K 7631-1: 1997 (test method for total light transmittance of plastic-transparent material) is 50% or more. , 80% or more is more preferable.

[Concave and convex layer]
The uneven layer 13 is formed on the base material 11. Further, as shown in FIG. 1, the base layer 12 may be provided between the uneven layer 13 and the base material 11, and the uneven layer 13 may be formed directly on the base layer 12. The concavo-convex layer 13 is a layer in which a concavo-convex structure on the order of nanometers is formed on the surface, and the concavo-convex structure serves as a diffraction grating and has a function of improving light extraction efficiency. Further, since the concavo-convex layer 13 has a concavo-convex structure on the order of nanometers, light extraction in the waveguide mode is good.

Further, the uneven layer 13 has a thickness B of 10 nm or more and 2000 nm or less in the concave portion of the above-mentioned uneven structure. Further, it is preferable that the thickness B of the concave-convex layer 13 in the concave portion is 10 nm or more and 1000 nm or less. Further, the height A of the convex portion of the uneven layer 13 is preferably 10 nm or more and 1000 nm or less, and the pitch of the convex portion is preferably 100 nm or more and 2000 nm or less. When the concavo-convex structure of the concavo-convex layer 13 is within the above range, light extraction by the waveguide mode is good.

The uneven layer 13 may be formed by any method such as transfer method, rubbing of a polymer film, direct injection molding using a 3D printer, etc., but it is preferably formed by nanoimprint technology. In order to form the concavo-convex structure of the concavo-convex layer 13 by using the nanoimprint technique, the mother mold is pressed against the layer for producing the concavo-convex layer 13 to transfer the concavo-convex structure of the mother mold. At this time, if the thickness B of the above-mentioned concave portion is too small, a sufficient amount of material cannot be supplied to the convex portion depending on the pressure distribution that presses the master mold when transferring the shape of the master mold. , The shape of the convex part tends to be partially non-uniform. In this case, the uniformity of the shape of the convex portion in the concave-convex layer 13 is lowered, the optical characteristics are deteriorated, and the light extraction efficiency is lowered.

Further, if the thickness B in the above-mentioned recess is not provided, the mother die comes into contact with the base material 11 side, so that the base material 11 and the base layer 12 and the like are scratched, damaged, and damaged. In this case, the mother mold itself is damaged due to the contact between the mother mold and the base material 11 side. In this case, the surface of the master mold is damaged, and the uneven structure is deformed. Also in this case, since the concave-convex structure of the concave-convex layer 13 to which the concave-convex structure of the master mold is transferred deviates from the design, the optical characteristics are deteriorated and the light extraction efficiency is lowered.

Further, when the nanoimprint technique is used, it is preferable to increase the uniformity of the film thickness of the layer for forming the uneven layer 13 before transferring the matrix. Before transferring the mother mold, the higher the uniformity of the film thickness of the layer, the easier it is to make the shape of the convex portion formed by the transfer of the mother mold uniform. In order to improve the uniformity of the film thickness, it is necessary to give the layer a certain thickness, and it is easy to achieve the uniformity of the shape of the uneven layer 13 by giving the layer a sufficient thickness. If the layer before formation has a certain thickness, a certain thickness remains in the concave portions of the concave-convex layer 13 after the uneven structure of the master mold is transferred. Therefore, by designing the thickness B of the concave portion of the concave-convex layer 13 to a thickness that can enhance the uniformity of the film thickness, the optical characteristics of the concave-convex layer 13 are improved and the light extraction efficiency is further improved. be able to.

Therefore, in order to produce the concavo-convex layer 13 having good optical characteristics by using the nanoimprint technique with high productivity, it is preferable that the thickness B in the concave portion of the concavo-convex layer 13 has a certain thickness. .. That is, the larger the thickness B in the concave portion of the concave-convex layer 13, the lower the possibility of contact between the mother mold and the base material 11 side, and the higher the shape stability of the convex portion of the concave-convex layer 13.

However, as the thickness B of the uneven layer 13 increases, the overall thickness C of the uneven layer 13 increases. That is, the total amount of the material constituting the uneven layer 13 increases. When the total amount of the materials constituting the uneven layer 13 increases, the amount of outgas generated from the uneven layer 13 increases, which may affect the reliability of the organic EL element 10. Therefore, the larger the volume of the uneven layer 13, the higher the possibility that the reliability of the electronic device formed on the organic EL element 10 will decrease.

As described above, considering the reliability of the electronic device formed on the organic EL element 10, it is necessary to reduce the total amount of the materials constituting the concave-convex layer 13. However, in the uneven layer 13, the height A of the convex portion, the pitch of the convex portion, and the like are determined by the optical design, so that the degree of freedom in design is low. Therefore, in order to reduce the total amount of the material constituting the uneven layer 13, it is difficult to change the shape of the convex portion that strongly affects the optical characteristics. That is, in order to reduce the amount of outgas generated from the uneven layer 13, it is necessary to reduce the amount of the portion other than the convex portion having a large optical influence.

As described above, from the viewpoint of reliability of the electronic device formed on the organic EL element 10, it is preferable to make the thickness B in the concave portion of the concave-convex layer 13 as small as possible. When the thickness B in the concave portion is sufficiently small, or when the concave-convex layer 13 does not have the thickness B, the amount of outgas generated from the concave-convex layer 13 can be sufficiently small, and the organic EL element 10 can be used. It is possible to suppress the deterioration of reliability due to the influence of the outgas of the electronic device formed on the surface.

From the above viewpoint, in the organic EL element 10 having the uneven layer 13 manufactured by using the nanoimprint technology, in order to suppress the deterioration of the reliability of the electronic device due to outgas without lowering the light extraction efficiency, the uneven layer It is necessary to optimize the thickness B of the recess of 13.

In the organic EL element 10, in order to suppress a decrease in shape stability and productivity of the concave-convex layer 13, it is preferable that the thickness B in the concave portion is 10 nm or more. Further, from the viewpoint of outgas generated from the uneven layer 13, it is preferable that the thickness B of the concave portion of the concave-convex layer 13 is 2000 nm or less. As described above, by setting the thickness B of the concave portion of the concave-convex layer 13 to 10 nm or more and 2000 nm or less, the deterioration of the shape stability and productivity of the concave-convex layer 13 and the reliability of the organic EL element 10 is sufficiently small. It can be suppressed to the range.

Further, it is preferable that the height A of the convex portion of the uneven layer 13 is 10 nm or more and 1000 nm or less. The height of the convex portion of the uneven layer 13 is a value mainly required by the optical design, but by setting the thickness A of the convex portion within the above range, the optical requirement and the generation of outgas are generated. It is possible to achieve both the problem of controlling the amount.

Further, if the average thickness of the uneven layer 13 exceeds 2500 nm, the total amount of the materials constituting the uneven layer 13 becomes too large, so that the reliability of the electronic device formed on the organic EL element 10 due to the outgas may decrease. There is sex. Further, as described above, in order to secure the thickness B in the concave portion of the concave-convex layer 13, it is preferable that the average thickness is 100 nm or more. Therefore, it is preferable that the average thickness of the uneven layer 13 is 100 nm or more and 2500 nm or less.

(material)
As the material for forming the uneven layer 13, a conventionally known material applicable to the nanoimprint technique can be used, and any of an organic material, an inorganic material, a resin material and the like can be applied. Examples thereof include resin materials such as epoxy resin, acrylic resin, urethane resin, melamine resin, urea resin, polyester resin, phenol resin, and crosslinked liquid crystal resin. Further, as the transparent inorganic layer forming material, for example, when a transparent inorganic layer is formed by a sol-gel method, a sol solution containing a metal material such as a metal alkoxide can be mentioned. As described above, the uneven layer 13 may be a cured resin layer obtained by curing the resin material or an inorganic layer formed by using a transparent inorganic material. Since it is suitable for production by nanoimprint technology, it is preferable to use a resin material.

The uneven layer 13 may have a one-dimensional lattice in which striped unevenness is uniformly arranged, a two-dimensional lattice in which conical or pillar-shaped unevenness is arranged, and a shape having other unevenness structures. Not particularly limited. For example, the arrangement of the uneven layers is preferably a square lattice shape, a triangular lattice shape, a honeycomb lattice shape, or the like, and the arrangement is preferably repeated two-dimensionally. The concavo-convex layer 13 can be applied to the organic EL element 10 as long as it has a concavo-convex structure capable of improving the light extraction efficiency. For example, a general diffraction grating structure can be applied.

It is desirable that the uneven layer 13 has a two-dimensional periodic refractive index. This is because the light emitted from the light emitting layer is randomly generated in all directions, so in a general one-dimensional uneven layer having a periodic refractive index distribution only in one direction, only the light traveling in a specific direction is diffracted. However, it is difficult to improve the efficiency of light extraction. On the other hand, by making the refractive index distribution a two-dimensional distribution, the light traveling in all directions is subjected to effects such as diffraction and scattering by the uneven layer 13, so that the light extraction efficiency is likely to be improved.

[Barrier layer]
The barrier layer 14 is formed between the uneven layer 13 and the first electrode 15. The barrier layer 14 is formed so as to follow the uneven shape of the surface of the uneven layer 13. Therefore, the barrier layer 14 has an uneven shape on the front surface and the back surface (the surface on the base material 11 side), respectively. The height D of the convex portion in the uneven shape of the surface of the barrier layer 14 is within ± 20% of the height A of the convex portion in the concave-convex layer 13. Further, since it is preferable to have higher followability from the viewpoint of light extraction efficiency, the height D of the convex portion in the uneven shape of the surface of the barrier layer 14 is ± 10 of the height A of the convex portion in the uneven layer 13. It is preferably within%.

Further, the barrier layer 14 is preferably a layer formed by a dry process. This is because when the wet process is used, the uneven shape of the surface of the uneven layer 13 is flattened by the coating liquid, and the followability of the barrier layer 14 tends to decrease. Further, as compared with the wet process, the film formed by the dry process generates less outgas, and the reliability of the organic EL element 10 is less likely to be lowered.

The thickness of the barrier layer 14 is not particularly limited, and is preferably 100 nm or more, more preferably 200 nm or more, for example, in consideration of barrier properties. Further, from the viewpoint of the followability of the uneven shape and the film forming property, the upper limit of the thickness is preferably 1000 nm or less.

Further, the barrier layer 14 preferably has a water vapor transmission rate of less than 0.1 g / ( ^m 2.24 h). The water vapor transmission rate of the barrier layer 14 is a value measured by a method according to JIS K 7129-1992. The barrier layer 14 has a water vapor transmission rate (25 ± 0.5 ° C., relative humidity 90 ± ² % RH) of less than 0.1 g / (m 2.24 h) and 0.01 g / ( ^m 2.24 h) or less. It is preferably 0.001 g / ( ^m 2.24 h) or less, and more preferably 0.001 g / (m 2.24 h) or less.

The barrier layer 14 preferably contains a silicon compound formed by a dry process as a main component. By using the silicon compound formed by the dry process as the main component of the barrier layer 14, it is possible to efficiently prevent the permeation of outgas, moisture and the like released from the uneven layer 13.

Examples of the silicon compound constituting the barrier layer 14 include silicon oxide, silicon nitride, silicon nitride, silicon carbide, and silicon nitride. In particular, from the viewpoint of barrier properties, it is preferable that the barrier layer 14 contains silicon nitride as a main component.

The barrier layer 14 can be suitably used as long as it is a dry process that has low water vapor transmission rate and can form a dense film with low film stress. For example, a vacuum vapor deposition method using silicon as a raw material (resistive heating, EB method, etc.), a magnetron sputtering method using a target containing silicon, an ion plating method, and plasma CVD using an organic silicon compound or silicon dioxide as a raw material. (Chemical Vapor Deposition) method or the like can be used.

Further, the barrier layer 14 may be formed into a composite film or a laminated film in which a film containing a silicon compound having the same composition or a different composition as a main component is combined by a multi-step film formation in a dry process. In the case of such a composite film or a laminated film, the function as the barrier layer 14 may be exhibited as a whole.

[1st electrode / 2nd electrode]
In the organic EL element 10, one of the first electrode 15 and the second electrode 17 serves as an anode of the organic EL element 10, and the other serves as a cathode. Further, in the organic EL element 10 shown in FIG. 1, the first electrode 15 is made of a transparent conductive material, and the second electrode 17 is made of a highly reflective conductive material. When the organic EL element 10 is a top emission type or a double-sided light emitting type, the first electrode 15 and the second electrode 17 are each made of a highly reflective material or a transparent conductive material.

The first electrode 15 and the second electrode 17 are formed by using a conductive material having a volume resistivity of ^10-5 Ωcm or more and 1 × 10 ^-3 Ω · cm or less. The volume resistivity can be obtained by measuring the sheet resistance measured according to the resistivity test method by the four-probe method of conductive plastic of JIS K 7194-1994 and the film thickness. The film thickness can be measured using a contact type surface shape measuring device (for example, DECTAK) or a light interference surface shape measuring device (for example, WYKO).

When the first electrode 15 and the second electrode 17 are formed of a transparent conductive material, they can be formed by using a metal thin film such as gold, silver, or aluminum, or a metal oxide having light transmittance. As a method for forming the first electrode 15 and the second electrode 17, a dry process method such as a vapor deposition method or a sputtering method can be used.

The metal oxide that can be used as the transparent conductive material is not particularly limited as long as it is a material having excellent conductivity. Examples of the metal oxide that can be used for the first electrode 15 include ATO (Sb-doped SnO), AZO (Al-doped ZnO), CeO ₂ , Ga ₂ O ₃ , GZO (Ga-doped ZnO), and ICO (indium cerium oxide). , IGZO (Indium Gallium Zinc Oxide), ITO (Indium Tin Oxide), IWZO (Indium Tin Oxide), IZO (Indium Zinc Oxide / Zinc Oxide), La ₂ Ti ₂ O ₇ , Nb ₂ O ₅ , SnO ₂ , Ta ₂ O ₅ , Ti ₂ O ₃ , Ti ₃ O ₅ , Ti ₄ O ₇ , TiO, TiO ₂ , ZnO, ZnS, ZrO ₂ , ZTO (zinc oxide composite oxide) and the like. As the transparent conductive material, IZO, IGO, and IWZO are preferable, and IZO is particularly preferable.

When a metal thin film is used as the transparent conductive material, it is preferable to use silver or an alloy containing silver as a main component. The principal component is the component having the highest composition ratio among the constituent components. Specifically, it is preferable that silver is contained in an amount of 60 atomic% (atomic%) or more with respect to all the atoms constituting the transparent conductive material. Further, from the viewpoint of conductivity, it is more preferable that silver is contained in an amount of 90 atomic% or more, and it is further preferable that silver is contained in an amount of 97 atomic% or more.

When the first electrode 15 and the second electrode 17 are formed of a highly reflective conductive material, it is preferable to use a material having high reflectance, and it is preferable to use Ag or an alloy containing Ag as a main component. Also, for example, sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, indium, lithium. / Aluminum mixture, rare earth metal, etc. can also be used.

[Light emitting unit]
The light emitting unit 16 is a light emitting body configured to have a light emitting layer containing at least an organic compound. Further, the light emitting unit 16 is mainly composed of an organic functional layer such as a hole transport layer and an electron transport layer together with the light emitting layer. The light emitting unit 16 is sandwiched between a pair of electrodes consisting of a first electrode 15 and a second electrode 17, and holes (holes) supplied from each electrode and electrons are recombinated in the light emitting layer. It emits light. The organic EL element may be provided with a plurality of the light emitting units according to the desired light emitting color.

In the organic EL element 10, the layer structure of the light emitting unit 16 is not limited, and may be a general layer structure. For example, when the first electrode 15 functions as an anode (anode) and the second electrode 17 functions as a cathode (cathode), the light emitting unit 16 is in order from the first electrode 15 side [hole injection layer / hole transport]. An example is a configuration in which a layer / light emitting layer / electron transport layer / electron injection layer] is laminated. The hole injection layer and the hole transport layer may be provided as the hole transport injection layer. The electron transport layer and the electron injection layer may be provided as an electron transport injection layer. Further, among these light emitting units 16, for example, the electron injection layer may be made of an inorganic material.

In addition to these layers, the light emitting unit 16 may have a hole blocking layer, an electron blocking layer, or the like laminated at necessary locations. Further, the light emitting layer may have each color light emitting layer that generates light emitted in each wavelength region, and each of these color light emitting layers may be laminated via a non-light emitting auxiliary layer. The auxiliary layer may function as a hole blocking layer and an electron blocking layer. Further, the second electrode 17, which is a cathode, may also have a laminated structure, if necessary. Further, the organic EL element 10 may be an element having a so-called tandem structure in which a plurality of light emitting units 16 including at least one light emitting layer are laminated.

Specific examples of the tandem organic EL element include, for example, US Pat. No. 6,337,492, US Pat. No. 7,420,203, US Pat. No. 7,473,923, US Pat. No. 6,872,472, and US Pat. No. 6,107,734. Japanese Patent No. 6337492, International Publication No. 2005/009087, Japanese Patent Application Laid-Open No. 2006-228712, Japanese Patent Application Laid-Open No. 2006-24791, Japanese Patent Application Laid-Open No. 2006-49393, Japanese Patent Application Laid-Open No. 2006-49394. , Japanese Patent Application Laid-Open No. 2006-49396, Japanese Patent Application Laid-Open No. 2011-966679, Japanese Patent Application Laid-Open No. 2005-340187, Japanese Patent No. 4711424, Japanese Patent No. 349661, Japanese Patent No. 3884564, Japanese Patent No. 4213169, Japanese Patent Application Laid-Open No. Japanese Patent Application Laid-Open No. 2010-192719, Japanese Patent Application Laid-Open No. 2009-0762929, Japanese Patent Application Laid-Open No. 2008-078441, Japanese Patent Application Laid-Open No. 2007-059848, Japanese Patent Application Laid-Open No. 2003-272860, Japanese Patent Application Laid-Open No. 2003-045676, International Publication No. Examples thereof include the element configuration and constituent materials described in 2005/094130 and the like.

[Underground layer]
In the organic EL element 10, the base layer 12 is provided as needed. The base layer 12 is arranged between the base material 11 and the uneven layer 13, and the uneven layer 13 is provided in direct contact with the base layer 12. In order to produce the concavo-convex structure of the concavo-convex layer 13 described above by using the nanoimprint technique, it is preferable that the film thickness of the layer forming the concavo-convex structure is as uniform as possible. Further, in order to minimize the amount of outgas generated from the uneven layer 13, it is preferable to make the layer for forming the uneven layer 13 thin. Therefore, the base layer 12 having a high affinity with the material forming the uneven layer 13 is provided so that the uniformity of the film thickness can be improved even if the layer for forming the uneven layer 13 is thinly formed. Is preferable.

The material constituting the base layer 12 is not particularly limited as long as it can form a layer having a high affinity with the material forming the uneven layer 13. For example, when the layer for forming the uneven layer 13 is produced by the coating method, it is preferable to use a material having a composition containing a silicon-containing compound having a high affinity for the coating liquid.

The composition and structure of the silicon-containing compound applicable to the base layer 12 are not limited. Further, there is no particular limitation on the method of forming the base layer 12 using the silicon-containing compound. For example, a method of forming a layer made of an inorganic compound such as silica by vacuum deposition or a CVD method, or a method of forming a silicon-containing polymer modified layer shown below can be applied. In particular, a silicon-containing polymer modified layer is preferable from the viewpoint of affinity with the coating liquid and productivity.

(Silicon-containing polymer modified layer)
The silicon-containing polymer reforming layer applied to the base layer 12 is formed by a modification treatment of a silicon-containing polymer having bonds such as silicon and oxygen (Si—O) and silicon and nitrogen (Si—N) in the repeating structure. Will be done. Although the silicon-containing polymer is converted to silica or the like by the modification treatment, it is not necessary to modify all the silicon-containing polymers in the silicon-containing polymer modified layer, and at least a part of the silicon-containing polymer, for example, the silicon-containing polymer on the ultraviolet irradiation surface side. Should be modified.

The thickness of the silicon-containing polymer modified layer can be appropriately set depending on the intended purpose, but is generally in the range of 10 nm to 10 μm.

Specific examples of the silicon-containing polymer include polysiloxane (including polysilsesquioxane) having a Si—O bond, polysilazane having a Si—N bond, and Si—O bond and Si—N bond in the repeating structure. Examples include polysiloxazan containing both. These can be used by mixing two or more kinds. It is also possible to laminate layers of different types of silicon-containing polymers.

The polysiloxane contains [-RaSiO _{1 /} 2-], [-RbSiO-], [-RcSiO _{3/ 2-} ], [-SiO 2-] and the like in the repeating structure. Ra, Rb and Rc independently have an alkyl group containing a hydrogen atom and 1 to 20 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, etc.) and an aryl group (for example, a phenyl group, an unsaturated alkyl group). Represents a substituent such as.
Polysilsesquioxane is a compound among the above polysiloxanes that has the same structure as silsesquioxane in its repeating structure. Sylsesquioxane is a compound having a structure represented by the above [ _{-RcSiO 3/} 2-].

The structure of polysilazane can be expressed by the following general formula (A).
[-Si (R ¹ ) (R ² ) -N (R ³ )-] ... General formula (A)
In the above general formula (A), R ¹ , R ² and R ³ independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkylsilyl group, an alkylamino group or an alkoxy group, respectively. ..

As another example of polysilazane that is ceramicized at a low temperature, a silicon alkoxide-added polysilazane obtained by reacting a polysilazane having a main skeleton consisting of a unit represented by the above general formula (A) with a silicon alkoxide (for example, JP-A-Pri). 5-238827 (see JP-A-5-238827), glycidol-added polysilazane obtained by reacting with glycidol (see, for example, JP-A-6-122852), alcohol-added polysilazane obtained by reacting with alcohol (eg, JP-A-6-240208). (See JP), metal carboxylate-added polysilazane obtained by reacting with a metal carboxylate (see, for example, JP-A-6-299118), and an acetylacetonate complex obtained by reacting an acetylacetonate complex containing a metal. Examples thereof include the added polysilazane (see, for example, JP-A-6-306329), the metal fine particle-added polysilazane obtained by adding metal fine particles (see, for example, JP-A-7-196986), and the like.

The silicon-containing polymer modified layer can be formed by forming a coating film using the above-mentioned coating liquid containing the silicon-containing polymer and subjecting the coating film to a modification treatment.
Examples of the coating film forming method include a roll coating method, a flow coating method, a spray coating method, a printing method, a dip coating method, a bar coating method, a cast film forming method, an inkjet method, and a gravure printing method.

As the coating liquid, a commercially available product in which polysilazane is dissolved in an organic solvent can be used. Examples of commercially available products that can be used include Aquamica NAX120-20, NN110, NN310, NN320, NL110A, NL120A, NL150A, NP110, NP140, SP140 manufactured by AZ Electronic Materials.

From the viewpoint of removing the organic solvent in the coating film, the formed coating film is preferably subjected to a drying treatment by heating. The heating temperature is preferably in the range of 50 to 200 ° C. The heating time is preferably set to a short time in order to prevent deformation of the base material 11. For example, when polyethylene terephthalate having a glass transition temperature of 70 ° C. is used for the base material 11, the temperature during the drying process can be set to 150 ° C. or lower in order to prevent deformation of the resin film.

Further, from the viewpoint of removing the moisture in the coating film, the formed coating film may be subjected to a drying treatment for dehumidifying while maintaining a low humidity environment. Since the humidity in a low humidity environment changes depending on the temperature, the relationship between the temperature and the humidity can be determined by the regulation of the dew point temperature. The preferred dew point temperature is 4 ° C. or lower (temperature 25 ° C./humidity 25%), the more preferable dew point temperature is −8 ° C. (temperature 25 ° C./humidity 10%) or less, and the more preferable dew point temperature is −31 ° C. (temperature 25 ° C./25%). Humidity is 1%) or less. To facilitate the removal of moisture, it may be dried under reduced pressure. The pressure in vacuum drying can be selected in the range of normal pressure to 0.1 MPa.

As a method for modifying the coating film, a known method that causes less damage to the base material 11 can be used, and plasma treatment, ozone treatment, ultraviolet ray or vacuum ultraviolet irradiation treatment that can be treated at a low temperature are used. be able to. Above all, the irradiation treatment with vacuum ultraviolet rays is preferable because the deterioration of the barrier property due to the environment is unlikely to occur from the formation of the silicon-containing polymer modified layer to the formation of the transition metal oxide layer.

As the base layer 12, a silicon compound obtained by a dry process may be used. As the silicon compound by the dry process, the same structure as that of the barrier layer 14 described above can be used. It is preferable to adjust the thickness and composition of the silicon compound obtained by the dry process so as to have a high affinity with the material forming the uneven layer 13.

[Adhesive layer]
The pressure-sensitive adhesive layer 18 is used as a sealing agent for fixing the sealing base material 19 to the base material 11 and the second electrode 17 and sealing the light emitting unit 16. As the pressure-sensitive adhesive layer 18, a resin used for sealing a conventionally known organic EL element can be applied.

The coating of the pressure-sensitive adhesive layer 18 may be printed on the sealing base material 19 using a commercially available dispenser as in screen printing. The organic compound constituting the light emitting unit 16 may be deteriorated by the heat treatment. Therefore, the pressure-sensitive adhesive layer 18 is preferably one that can be adhesively cured from room temperature (25 ° C.) to 80 ° C. Further, the desiccant may be dispersed in the pressure-sensitive adhesive layer 18.

[Encapsulating base material]
The sealing base material 19 is a plate-shaped member that covers the upper surface of the pressure-sensitive adhesive layer 18 in order to seal the organic EL element 10, and is fixed to the base material 11 side by the pressure-sensitive adhesive layer 18. Further, the sealing base material 19 is not limited to a plate shape but may be in a film shape or the like.

As the sealing base material 19, a base material used for sealing a conventionally known organic EL element can be applied. For example, a glass substrate, a polymer substrate, a metal substrate and the like can be mentioned. Further, these materials may be thinned and a film-shaped sealing base material 19 may be used. In particular, since it is advantageous for thinning the element, it is preferable to use a polymer substrate or a metal substrate in the form of a thin film as the sealing base material 19. Further, the sealing base material 19 may be processed into an intaglio shape and used. In this case, the material of the sealing base material 19 described above is subjected to processing such as sandblasting and chemical etching to form a concave structure on the sealing base material 19.

Further, the sealing base material 19 has an oxygen permeability measured by a method conforming to JIS K 7126-1987 of 1 × 10 ^-3 ml / ( ^m 2.24 h · atm) or less, and conforms to JIS K 7129-992. It is preferable that the water vapor transmission rate (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured by the above method is 1 × 10 ^-3 g / ( ^m 2.24 h) or less.

<2. Manufacturing method of organic electroluminescence device>
Next, a method for manufacturing the organic EL element 10 shown in FIG. 1 will be described.

The method for manufacturing the organic EL element 10 includes a step of forming the base layer 12 on the base material 11, a step of forming a coating film containing the uneven layer forming material on the base layer 12, and a coating film containing the uneven layer forming material. Includes a step of transferring the uneven structure of the master mold to form the uneven layer 13. It also includes a step of forming the barrier layer 14 on the uneven layer 13 and a step of forming the first electrode 15 on the barrier layer 14. Further, the step of forming the light emitting unit 16 on the first electrode 15 and the step of forming the second electrode 17 on the light emitting unit 16 are included. Here, in the step of forming the second electrode 17 from the step of forming the barrier layer 14, the surface of each layer is formed so as to follow the concave-convex structure of the concave-convex layer 13. Further, a sealing step of bonding the sealing base material 19 on the second electrode 17 via the pressure-sensitive adhesive layer 18 may be included. Hereinafter, each step for manufacturing the organic EL element 10 will be described.

[Step of forming the base layer]
First, the base layer 12 is formed on the base material 11. As the base layer 12, for example, a silicon-containing polymer modified layer is formed on the base material 11. For the silicon-containing polymer modified layer, for example, a liquid containing perhydropolysilazane is applied by the following method, and then the perhydropolysilazane is modified to form an underlayer.

First, a solution containing perhydropolysilazane is prepared as a silicon-containing compound. Then, the prepared solution is subjected to a base material 11 by using a roll coating method, a flow coating method, a spray coating method, a printing method, a dip coating method, a bar coating method, a cast film forming method, an inkjet method, a gravure printing method, or the like. Apply on top. After forming the coating film, in order to remove the organic solvent in the coating film, the formed coating film is heated to 50 to 200 ° C. and dried.

Further, the dried coating film is subjected to, for example, vacuum ultraviolet irradiation treatment to modify the coating film. The vacuum ultraviolet irradiation treatment is performed using, for example, an Xe excimer lamp with an illuminance of 1 mW / cm ² to 10 W / cm ² and an irradiation energy amount of 0.1 to 10.0 J / cm ² for 0.1 seconds to 10 minutes. , Irradiate with vacuum ultraviolet rays.

[Making a mother mold]
It is preferable to form a surface shape (concave and convex shape) in the master mold so that the height of the convex portion is 10 nm or more and 100 nm or less. Further, it is preferable that the mother die has a surface shape in which the pitch of the convex portions is 100 nm or more and 2000 nm or less. For a master mold having a fine uneven structure, for example, a latent image is formed on a resist by using a technique such as optical drawing (mask exposure, reduced projection exposure, interference exposure, etc.), electron beam drawing, X-ray drawing, etc., and then developed. It can be produced by forming an uneven pattern. In particular, as a method for producing a matrix having a large-area uneven structure with high productivity, an optical drawing method such as two-luminous flux interference exposure is excellent. Further, the uneven structure of the master mold may be formed by electroforming technology from the uneven structure formed by the resist, and the shape is transferred to silicon, quartz glass, metal or the like by etching using the resist as a mask. You may. Further, a mold release agent may be applied to the mother mold.

(Specific mother mold manufacturing method: laser interference exposure method)
An ultraviolet laser (wavelength 266 nm) is used to perform immersion 2 light flux interference exposure at an inclination of 35 degrees with respect to the normal direction to form interference fringes on the resist. As the laser light source, "MBD266 manufactured by Coherent Co., Ltd." can be used. As the resist material, a negative resist in which the resist remains in the exposed portion, for example, "TDUR-009P manufactured by Tokyo Ohka Co., Ltd." can be used. The immersion exposure optical system has a beam diameter of 80 mm and masks areas other than the exposed area to form an unexposed portion.

Next, after developing the resist, a fine uneven structure having a drawing size of 50 mm square is formed on quartz glass (70 mm square, thickness 1.2 mm) by dry etching. Then, the uneven structure of the quartz glass is transferred step by step to the entire surface of a 1000 mm square resin substrate (acrylic resin, thickness 1 mm) by using nanoimprint (heat imprint) technology. By electroforming the resin substrate with Ni, a mother die (nickel mold, 1000 mm square, thickness 1 mm) can be manufactured.

(Film-shaped mother mold)
Further, a film-shaped master mold applicable to the production of the uneven layer 13 by the roll-to-roll method described later as a master mold and an imprint roll in which the film-shaped master mold is attached to the outer surface of the roll are produced. May be good.

The film-like matrix is, for example, a long and flexible silicone resin, polyethylene terephthalate (PET), polyethylene terenaphthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP), polymethylmethacrylate (PMMA). ), Polystyrene (PS), polyimide (PI), polyarylate and the like are used to form an uneven structure on the surface of this film. The uneven structure may be formed in direct contact with the film, or may be formed on a coating material such as a photocurable resin, a thermosetting resin, or a thermoplastic resin provided on the film.

Specifically, for example, the film wound around the roll is unwound to the downstream side, and the coating material is applied onto the film using a die coater or the like. Then, the outer peripheral surface of the transfer roll having a predetermined uneven structure formed on the surface is pressed against the coating material coated on the film, and the uneven pattern on the outer peripheral surface of the transfer roll is transferred to the coating film. At this time, energy rays such as ultraviolet rays and heating are performed to cure the coating material to which the uneven pattern is transferred. Finally, the transfer roll is separated from the coating material having the cured uneven structure, and the film is wound up by the take-up roll to prepare a film-shaped master mold. Further, if necessary, the uneven surface of the film-shaped master mold may be plated. As the plating, an electroless plating method and an electrolytic plating method can be applied.

[Step of forming a coating film containing a material for forming an uneven layer]
The method for producing the concavo-convex layer 13 is not particularly limited, and for example, International Publication No. 2011/007878, JP-A-11-283751, JP-A-2013-109932, JP-A-2013-157340, JP-A-2008- The methods described in Japanese Patent Application Laid-Open No. 290330, Japanese Patent Application Laid-Open No. 2013-219334, etc. can be applied. In particular, since productivity is improved in the production of the organic EL element 10 using a flexible film, the roll-to-roll method described in JP-A-2008-290330, JP-A-2013-219334, etc. It is preferable to apply the method for producing the uneven layer 13 according to the above.

2 to 4 show an example of a process diagram for forming the uneven layer 13. The method for manufacturing the uneven layer 13 is a step of applying a material for forming the uneven layer 13 on the base material 11 (concave and convex layer forming material), and curing the uneven layer forming material while pressing a mother mold for forming the uneven layer. It has a step and a step of releasing the master mold.

(Preparation of liquid composition)
First, the above-mentioned uneven layer forming material is dissolved or dispersed in a solvent to prepare a liquid composition containing the uneven layer forming material. As the uneven layer forming material, the above-mentioned resin material or transparent inorganic material can be used. As the solvent, lower alcohols having about 1 to 4 carbon atoms, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, esters such as methyl acetate and ethyl acetate, and hydrocarbons such as toluene and xylene are selected. be able to.

(Application of uneven layer forming material)
Next, as shown in FIG. 2, a liquid composition containing the uneven layer forming material is applied onto the base material 11 to form a coating film 13A containing the uneven layer forming material. At this time, the coating film 13A containing the material for forming the uneven layer is formed to have a thickness at least equal to or larger than the thickness of the convex portion of the prepared master mold 20. More specifically, the coating film 13A is formed to have an average thickness of 100 nm or more and 2500 nm or less in consideration of the uneven structure of the master mold.

As a method for applying the liquid composition, a coating method such as a spin coating method, a bar coating method, a dip coating method, a die coating method, or an inkjet method can be used. In the liquid composition of the uneven layer forming material, it is necessary to appropriately select conditions such as viscosity, molecular weight, and wettability to the prepared mother mold 20 according to the uneven size. When the uneven structure is fine, the lower the viscosity and the lower the molecular weight, the easier it is for the liquid to enter the uneven structure of the master mold 20. Further, it is desirable that the wettability with the mother die 20 is good.

When the liquid composition is applied onto the master mold 20 by using an inkjet method, the liquid composition is filled in the inkjet head, discharged from a nozzle, and applied to a necessary portion on the surface of the master mold 20. As the inkjet method, a piezo-type inkjet method using a piezoelectric element, a bubble jet method, or the like can be used, and a coating liquid having a wide viscosity from several mPa · s to 100 mPa · s can be discharged. It is preferable to use the piezo type inkjet method.

(Attachment with mother mold)
Next, as shown in FIG. 3, the master mold 20 is bonded and pressed against the coating film 13A containing the uncured uneven layer forming material before the applied uneven layer forming material is cured. Then, the uneven layer forming material is cured in a state where the mother die 20 and the coating film 13A are bonded to each other. As a result, the concavo-convex layer 13 to which the concavo-convex structure of the master mold 20 is transferred is formed on the base material 11.

To cure the uneven layer forming material, the uneven layer forming material is heated or the uneven layer forming material is irradiated with active rays such as ultraviolet rays and electron beams. At this time, volatilization of the solvent in the coating liquid, drying treatment, and the like may be performed at room temperature. Further, in order to accelerate drying and curing, it may be exposed to warm air in an environment of a certain temperature. However, if the temperature rises above a certain temperature, inconveniences such as deformation of the coating film 13A containing the base material 11 and the material for forming the uneven layer and generation of bubbles in the drying process occur.

(Release)
Next, as shown in FIG. 4, the mother die 20 is released from the formed uneven layer 13. The mold release of the master mold 20 is performed when the material for forming the uneven layer is hardened to the extent that it can maintain its own shape. If the mold release is too fast, the uneven structure of the uneven layer forming material formed at the time of mold release tends to collapse. In addition, it is preferable to release the mold immediately after the cured state is reached to the extent that the shape does not collapse.

(Roll-to-roll method)
When the uneven layer 13 is formed by the roll-to-roll method using the above-mentioned film-shaped mother mold, the above-mentioned coating of the uneven layer forming material, bonding with the mother mold 20, and mold release are performed in a series. This is done in the roll-to-roll device. For example, the base material 11 is unwound from the roll, and a liquid composition containing the uneven layer forming material is applied onto the base material 11 or the base layer 12 to form the coating film 13A. As a method for applying the liquid composition, a method applicable to roll-to-roll can be selected from the above-mentioned application methods.

Then, the film-shaped master mold 20 or the imprint roll having the master mold 20 is pressed against the coating film 13A containing the uneven layer forming material to transfer the concave-convex structure. For example, a film-shaped master mold 20 is sent between the pressing roll and the base material 11, and the master mold 20 is pressed against the coating film 13A by the pressing roll, and then the base material 11 and the film-shaped master mold 20 Are transported at the same time. Alternatively, the base material 11 is conveyed along the surface of the imprint roll at a constant distance while the imprint roll is pressed against the coating film 13A.

Further, with the mother die 20 pressed against the coating film 13A, energy rays are irradiated and heated to cure the uneven layer forming material. When the uneven layer forming material is cured by heating such as a thermosetting resin or a sol-gel method, the uneven layer forming material may be heated using a heating roll. Then, by transporting the base material 11, the mother die 20 can be peeled off from the cured material for forming the uneven layer, and the uneven layer 13 can be produced.

The transport speed is preferably about 0.05 to 40 m / min, more preferably 1 to 20 m / min. If the transfer speed is 0.05 m / min or more, sufficient productivity can be ensured. On the other hand, when the transfer speed is 40 m / min or less, the transfer time by the film-shaped master mold or the imprint roll can be sufficiently secured, and the surface of the uneven layer forming material can be sufficiently plastically deformed.

[Step of forming a barrier layer]
The barrier layer 14 forms a layer containing a silicon compound by using the above-mentioned dry process. As an example of the dry process for forming the barrier layer 14, a plasma CVD method using an organosilicon compound will be described. In the formation of the barrier layer 14 by the plasma CVD method, a silicon compound is formed from the reaction product of the organosilicon compound.

(Film formation by dry process)
Examples of the organic silicon compound used in the plasma CVD method include hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, and trimethylsilane. , Diethylsilane, propylsilane, phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, octamethylcyclotetrasiloxane and the like. Among them, hexamethyldisiloxane and 1,1,3,3-tetramethyldisiloxane are preferable from the viewpoint of handling in film formation and the barrier property of the obtained barrier layer 14. In addition, these organosilicon compounds can be used alone or in combination of two or more.

For example, when the barrier layer 14 made of the reaction product of hexamethyldisiloxane is formed by using the plasma CVD method, the molar amount of oxygen as the reaction gas with respect to the molar amount (flow rate) of hexamethyldisiloxane as the raw material gas is used. The amount (flow rate) is preferably 12 times or less (more preferably 10 times or less), which is the stoichiometric ratio. By supplying hexamethyldisiloxane and oxygen in such a ratio, carbon atoms and hydrogen atoms in hexamethyldisiloxane that are not completely oxidized are incorporated into the barrier layer 14. Therefore, the obtained barrier layer 14 can be provided with excellent barrier properties and bending resistance. The lower limit of the molar amount of oxygen in the film-forming gas is preferably 0.1 times or more, more preferably 0.5 times or more the molar amount of hexamethyldisiloxane.

Further, in the film formation using the dry process, since a trace amount of gas other than the introduced gas is present, it is rare that the component is as stoichiometric. Specifically, Si ₃ N ₄ is a representative value of stoichiometry, but there is a certain range of ratios in the actual film, and these are included and treated as Si N. The above-mentioned atomic number ratio can be obtained by a conventionally known method, but can be measured by, for example, an analyzer using X-ray Photoelectron Spectroscopy (XPS) or the like.

[Step of forming the first electrode]
The method for forming the first electrode 15 on the barrier layer 14 is not particularly limited. For example, when the above-mentioned metal oxide or metal thin film is formed, it can be formed by a vacuum vapor deposition method or a sputtering method using the above-mentioned materials. If it is a vacuum vapor deposition method or a sputtering method, the first electrode 15 having high flatness can be formed extremely quickly without exposing the base material 11 to a high temperature environment.

Examples of the applicable vapor deposition method include a resistance heating vapor deposition method, an electron beam vapor deposition method, an ion plating method, and an ion beam vapor deposition method. As the vapor deposition apparatus, for example, a BMC-800T vapor deposition machine manufactured by Syncron can be used.

The sputtering methods include a two-pole sputtering method, a magnetron sputtering method, a DC sputtering method, a DC pulse sputtering method, an RF (high frequency) sputtering method, a dual magnetron sputtering method, a reactive sputtering method, an ion beam sputtering method, a bias sputtering method, and a bias sputtering method. A known sputtering method such as the opposed target sputtering method can be appropriately used. Specific commercially available sputtering equipment includes magnetron sputtering equipment manufactured by Osaka Vacuum Co., Ltd., various sputtering equipment manufactured by ULVAC (for example, multi-chamber type sputtering equipment ENTRON ^TM -EX W300), and L-430S-FHS sputtering equipment manufactured by Anerva. Etc. can be used.

If it is a vacuum vapor deposition method or a sputtering method, the first electrode 15 having high flatness can be formed at an extremely high speed. Further, when the first electrode 15 is formed on the uneven layer 13 and the first electrode 15 is formed by using a metal oxide, the forming speed is preferably 0.3 nm / sec or more. The formation rate of the first electrode 15 is more preferably in the range of 0.5 to 30 nm / sec, and particularly preferably in the range of 1.0 to 15 nm / sec. Further, the temperature at the time of film formation is preferably in the range of −25 to 25 ° C. The ultimate vacuum before the start of film formation is preferably 3 × 10 ^-3 Pa or less, more preferably 7 × 10 ^-4 Pa or less.

[Step of forming a light emitting unit]
Next, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are formed in this order on the first electrode 15 to form a light emitting unit 16. As a film forming method for each of these layers, there are a spin coating method, a casting method, an inkjet method, a vapor deposition method, a printing method, etc. The vacuum deposition method or the spin coating method is particularly preferable. Further, different film forming methods may be applied to each layer. When the ^thin -film deposition method is adopted for the film formation of each of these layers, the vapor deposition conditions differ depending on the type of compound used, etc., but generally, the boat heating temperature is 50 to 450 ° ^C. It is preferable to appropriately select each condition within the range of Pa, the vapor deposition rate of 0.01 to 50 nm / sec, the substrate temperature of -50 to 300 ° C., and the layer thickness of 0.1 to 5 μm.

[Step of forming the second electrode]
Next, the second electrode 17 is formed on the light emitting unit 16 by an appropriate film forming method such as a thin film deposition method or a sputtering method. At this time, the second electrode 17 is formed into a pattern in which the terminal portion is pulled out from above the light emitting unit 16 to the peripheral edge of the base material 11 while maintaining the insulating state with respect to the first electrode 15 by the light emitting unit 16.

[Sealing process]
Next, the pressure-sensitive adhesive layer 18 and the sealing base material 19 are placed on the base material 11 so as to cover at least the light emitting unit 16 with the extraction electrode of the first electrode 15 and the terminal portion of the second electrode 17 exposed. Seal with. First, a resin layer for forming the pressure-sensitive adhesive layer 18 is provided on one surface of the sealing base material 19, and the sealing base material 19 with resin is prepared. Then, the resin-attached sealing base material 19 is placed so that the resin layer side of the resin-attached sealing base material 19 covers the base material 11, the first electrode 15, the light emitting unit 16, and the side surfaces and the upper surface of the second electrode 17. Paste them together. After bonding, the resin layer is cured by heating or the like to form the pressure-sensitive adhesive layer 18.
By the above steps, the organic EL element 10 sealed with the pressure-sensitive adhesive layer 18 and the sealing base material 19 can be manufactured.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "%" is used in the examples, it represents "mass%" unless otherwise specified.

<Manufacturing of organic EL element of sample 101>
[Base material]
As a base material, a transparent resin base material having a clear hard coat layer on both sides, a polyethylene terephthalate (abbreviation: PET) film with a clear hard coat layer (CHC) manufactured by Kimoto Co., Ltd. (The clear hard coat layer is mainly composed of acrylic resin. It was composed of a UV curable resin and had a PET thickness of 125 μm).

[Preparation of the first electrode]
Next, an amorphous ITO film as a first electrode was produced on the above-mentioned substrate with a thickness of 300 nm. For the ITO film, a commercially available ITO target and an L-430S-FHS sputtering device manufactured by Anerva are used, Ar: 20 sccm, O ₂ : 1 sccm, sputtering pressure: 0.25 Pa, at room temperature, target side power: 1000 W, target. -Substrate distance: Fabricated by RF sputtering under the condition of 86 mm. Further, the substrate was heated to 100 ° C. during the sputtering film formation to prepare a crystalline ITO film. The thickness of the ITO film was 150 nm.

[Making a light emitting unit]
The crucible for vapor deposition in the vacuum vapor deposition apparatus was filled with the constituent materials of each layer of the light emitting unit in the optimum amount for producing the organic EL element. As the crucible for vapor deposition, a crucible made of a resistance heating material such as molybdenum or tungsten was used.

The following compounds α-NPD, BD-1, GD-1, RD-1, H-1, H-2 and E-1 were used as constituent materials for each layer of the light emitting unit.

First, the vacuum was reduced to 1 × 10 ^-4 Pa, the crucible for vapor deposition filled with the compound α-NPD was energized and heated, and the film was deposited on the first electrode at a vapor deposition rate of 0.1 nm / sec. A hole injection transport layer having a layer thickness of 40 nm was formed.

Similarly, compounds BD-1 and H-1 are co-deposited at a vapor deposition rate of 0.1 nm / sec so that the concentration of compound BD-1 becomes 5%, and a fluorescent light emitting layer having a layer thickness of 15 nm and exhibiting a blue color is exhibited. Formed.
Next, the compounds GD-1, RD-1 and H-2 were deposited at 0.1 nm / sec so that the concentration of the compound GD-1 was 17% and the concentration of the compound RD-1 was 0.8%. Co-deposited at a rate to form a yellow phosphorescent layer with a layer thickness of 15 nm.

Then, compound E-1 was deposited at a vapor deposition rate of 0.1 nm / sec to form an electron transport layer having a layer thickness of 30 nm.

[Preparation of the second electrode]
Further, lithium fluoride (LiF) was deposited with a layer thickness of 1.5 nm and aluminum with a layer thickness of 110 nm to form a second electrode (cathode). The second electrode was formed in a shape in which the terminal portion was pulled out from the peripheral edge of the substrate in a state of being insulated by the light emitting unit.

A thin-film mask is used to form each layer, and the 4.5 cm × 4.5 cm region located in the center of the 5 cm × 5 cm substrate is used as the light emitting region, and the width is 0.25 cm over the entire circumference of the light emitting region. A non-light emitting region was provided.

[Sealing]
(Preparation of adhesive composition)
100 parts by mass of Opanol B50 (BASF, Mw: 340,000) as a polyisobutylene resin, 30 parts by mass of Nisseki polybutene grade HV-1900 (Mw: 1900) as a polybutene resin, hindered amine light stabilizer As a TINUVIN765 (manufactured by Ciba Japan, having a tertiary hindered amine group) 0.5 part by mass, as a hindered phenolic antioxidant IRGANOX1010 (manufactured by Ciba Japan, β-position of both hindered phenol groups is tertiary 0.5 parts by mass (having a butyl group) and 50 parts by mass of Eastocac H-100L Resin (manufactured by Eastman Chemical Co., Inc.) as a cyclic olefin polymer are dissolved in toluene to obtain a pressure-sensitive adhesive having a solid content concentration of about 25% by mass. The agent composition was prepared.

(Preparation of adhesive sheet for sealing)
As the barrier layer, a polyethylene terephthalate film Alpet 12/34 (manufactured by Asia Aluminum Co., Ltd.) on which aluminum (Al) is vapor-deposited is used, and the layer thickness of the pressure-sensitive adhesive layer formed after drying the prepared solution of the pressure-sensitive adhesive composition. Was applied to the aluminum side (barrier layer side) so as to have a thickness of 20 μm, and dried at 120 ° C. for 2 minutes to form an adhesive layer. Next, a peeling-treated surface of a polyethylene terephthalate film having a thickness of 38 μm was bonded to the formed pressure-sensitive adhesive layer surface as a peeling sheet to prepare a sealing pressure-sensitive adhesive sheet.

(Sealing)
In a nitrogen atmosphere, the release sheet was removed from the sealing adhesive sheet prepared by the above method, dried on a hot plate heated to 120 ° C. for 10 minutes, and then cooled to room temperature (25 ° C.). Then, a sealing pressure-sensitive adhesive sheet was laminated so as to completely cover the cathode, and the mixture was heated at 90 ° C. for 10 minutes. In this way, the organic EL element of the sample 101 was produced.

<Manufacturing of organic EL element of sample 102>
The organic EL element of the sample 102 was produced by the same method as the organic EL element of the sample 101 described above, except that the first electrode was produced of amorphous ITO by the following method.

[Preparation of the first electrode]
An amorphous ITO film as a first electrode was prepared on the above substrate with a thickness of 300 nm. For the amorphous ITO film, using a commercially available ITO target and an L-430S-FHS sputtering device manufactured by Anerva, Ar: 20 sccm, O ₂ : 1 sccm, sputtering pressure: 0.25 Pa, at room temperature, target side power: It was produced by RF sputtering under the conditions of 1000 W and target-board distance: 86 mm.

<Manufacturing of organic EL element of sample 103>
The organic EL element of the sample 103 was produced by the same method as the organic EL element of the sample 101 described above, except that the first electrode was produced by IZO using the following method.

[Preparation of the first electrode]
An IZO film as a first electrode was formed on the above substrate with a thickness of 300 nm. For the IZO film, a commercially available IZO target and an L-430S-FHS sputtering device manufactured by Anerva are used, Ar: 20 sccm, O ₂ : 1 sccm, sputtering pressure: 0.25 Pa, room temperature, target side power: 1000 W, target. -Made by RF sputtering under the condition of substrate distance: 86 mm.

<Manufacturing of organic EL element of sample 104>
The organic EL element of the sample 104 was produced by the same method as the organic EL element of the sample 101 described above, except that the first electrode was produced by AZO using the following method.

[Preparation of the first electrode]
An AZO (Al2O _{- 3} -ZnO) film as a first electrode was formed on the above-mentioned substrate with a thickness of 300 nm. For the AZO film, a commercially available AZO target and an L-430S-FHS sputtering device manufactured by Anerva are used, Ar: 20 sccm, O ₂ : 1 sccm, sputtering pressure: 0.25 Pa, room temperature, target side power: 1000 W, target. -Made by RF sputtering under the condition of substrate distance: 86 mm.

<Manufacturing of organic EL element of sample 105>
After preparing a base layer on the base material by the following method, an uneven layer was formed on the base layer by the following method. Further, the organic EL element of the sample 105 is formed by the same method as the organic EL element of the sample 103 described above, except that the first electrode is formed on the barrier layer after the barrier layer is formed on the uneven layer by the following method. Was produced.

[Underground layer]
N, N-diethylethanolamine was added as an amine catalyst to a 10% by mass dibutyl ether solution of perhydropolysilazane (PHPS) (Aquamica NN120-10, non-catalytic type, manufactured by AZ Electronic Materials) to prepare a coating solution. .. The amount of N, N-diethylethanolamine added was 1.0% by mass with respect to the coating liquid.
The above coating liquid is applied on a substrate with a wire bar so that the (average) layer thickness after drying is 300 nm, and is kept in an atmosphere of a temperature of 85 ° C. and a humidity of 55% RH for 1 minute to be dried. Further, a dehumidifying treatment was carried out in which the temperature was 25 ° C. and the humidity was 10% RH (dew point temperature −8 ° C.) for 10 minutes to form a polysilazane layer.
Next, the formed polysilazane layer was subjected to silica conversion treatment under atmospheric pressure using the following ultraviolet irradiation device and modification treatment conditions to obtain a silicon nitride compound film.

(Ultraviolet irradiation device)
Equipment: Excimer irradiation device MODEL MECL-M-1-200 manufactured by MD.com.
Irradiation wavelength: 172 nm
Lamp-filled gas: Xe

(Reform treatment conditions)
The substrate on which the polysilazane layer fixed on the operating stage was formed was modified under the following conditions.
Excimer lamp light intensity: 130 mW / cm ² (172 nm)
Distance between sample and light source: 1 mm
Stage heating temperature: 70 ° C
Oxygen concentration in the irradiator: 1.0%
Excimer lamp irradiation time: 5 seconds

[Concave and convex layer]
A fluorine-based UV curable resin (trade name "NIF" manufactured by Asahi Glass Co., Ltd.) was applied onto the base layer so as to have a predetermined dry film thickness. Next, the surface of the coating film of the fluorine-based UV curable resin is irradiated with ultraviolet rays under the condition of 600 mJ / cm ² while pressing the mother mold having the concave-convex structure with the depth of the recesses of 50 nm, and the fluorine-based UV is cured. The sex resin was cured. As a result, an uneven layer having a convex portion height A of 50 nm and an average thickness of 50 nm was produced.

[Preparation of barrier layer]
In the chamber of the magnetron sputtering apparatus (manufactured by Anerva, SPF-730H), a base material prepared up to an uneven layer was mounted. Next, the inside of the chamber of the magnetron sputtering apparatus was depressurized to an ultimate vacuum degree of 3.0 × 10 ^-4 Pa by an oil rotary pump and a cryopump. Si is used as a target, argon gas 7 sccm and nitrogen gas 26 sccm are introduced, high frequency power with a frequency of 13.56 MHz (input power 1.2 kW) is applied, and silicon with a gas pressure of 0.4 Pa and a film thickness of 500 nm. A compound (SiN) film was formed.

<Manufacturing of organic EL elements of sample 106 and sample 107>
In the preparation of the uneven layer, the coating thickness of the fluorine-based UV curable resin (trade name "NIF" manufactured by Asahi Glass Co., Ltd.) is changed, and the average thickness is shown in Table 1 below without changing the height A of the convex portion. The organic EL elements of the sample 116 and the sample 107 were produced by the same method as the organic EL element of the sample 105 described above except that the thickness was changed.

<Manufacturing of organic EL element of sample 108>
The organic EL element of sample 108 was produced by the same method as the organic EL element of sample 107 described above, except that the barrier layer was prepared of ZTO (zinc-tin composite oxide) by the following method.

[Preparation of barrier layer]
Ar: 20 sccm, O ₂ : 1 sccm, sputter pressure: 0.25 Pa, at room temperature, target using a commercially available ZTO target and Anerva's L-430S-FHS sputtering device on the substrate prepared up to the uneven layer. A ZTO film was prepared with a thickness of 500 nm under the conditions of a side power of 1000 W and a target-substrate distance of 86 mm. The ZTO film was prepared by RF sputtering.

<Manufacturing of organic EL element of sample 109>
The organic EL element of sample 109 was produced by the same method as the organic EL element of sample 107 described above, except that the first electrode was produced of crystalline ITO by the same method as that of sample 101 described above.

<Manufacturing of organic EL element of sample 110>
The organic EL element of the sample 110 was produced by the same method as the organic EL element of the sample 107 described above, except that the first electrode was produced of amorphous ITO by the same method as that of the sample 102 described above.

<Manufacturing of organic EL element of sample 111>
The organic EL element of the sample 111 was produced by the same method as the organic EL element of the sample 107 described above, except that the first electrode was produced by AZO using the same method as that of the sample 104 described above.

<Manufacturing of organic EL elements of samples 112 to 117>
In the production of the uneven layer, the coating thickness of the fluorine-based UV curable resin (trade name "NIF" manufactured by Asahi Glass Co., Ltd.) is changed, and the average thickness is shown in Table 1 below without changing the height A of the convex portion. The organic EL elements of the samples 112 to 117 were produced by the same method as the organic EL element of the sample 107 described above except that the thickness was changed.

<Manufacturing of organic EL element of sample 118>
As the barrier layer, the sample is prepared by the same method as the organic EL device of the above-mentioned sample 107, except that the silicon nitride compound film is prepared from perhydropolysilazane (PHPS) by the same method as the above-mentioned preparation of the base layer. 118 organic EL devices were manufactured.

<Manufacturing of organic EL element of sample 119>
The organic EL element of sample 119 was produced by the same method as the organic EL element of sample 107 described above, except that the organic layer made of α-NPD was produced instead of the barrier layer by the following method.

[Preparation of organic layer]
The crucible for vapor deposition in the vacuum vapor deposition apparatus was filled with α-NPD. As the crucible for vapor deposition, a crucible made of a resistance heating material such as molybdenum or tungsten was used. The inside of the device is depressurized to a vacuum degree of 1 × 10 ^-4 Pa, a crucible for vapor deposition filled with the compound α-NPD is energized and heated, and a thin film is deposited on the uneven layer at a vapor deposition rate of 0.1 nm / sec. A barrier layer having a thickness of 40 nm was formed.

<evaluation>
The organic EL devices of the prepared samples 101 to 119 were evaluated by the following methods.

[Thickness, followability]
Samples 105 to 119 on which the uneven layer was prepared are cut using FIB, the shape of the cut surface is observed using TEM, and the cross section of the uneven layer, the barrier layer, the first electrode, the light emitting unit, and the second electrode. I took a profile. After shooting, the height A of the convex portion of the uneven layer, the thickness B of the concave portion, and the thickness C of the convex portion are measured at 100 points or more at an arbitrary position, and the height A of the convex portion of the uneven layer is measured from the average value. The thickness B in the concave portion of the concave-convex layer and the thickness C in the convex portion of the concave-convex layer were determined. Further, the average thickness of the uneven layer was obtained from the average value of the thickness B in the concave portion of the concave-convex layer and the thickness C in the convex portion of the concave-convex layer. The thickness at the convex portion was measured at 100 points or more at an arbitrary position, and the average thickness of the barrier layer was obtained from the average value.
Further, in the barrier layer and the second electrode, the height D of the convex portion of the barrier layer and the height E of the convex portion of the second electrode are measured at an arbitrary position at 100 points or more, and the barrier layer is measured from the average value. The height D of the convex portion of the second electrode and the height E of the convex portion of the second electrode were obtained. Then, the height A of the convex portion of the uneven layer obtained by the above method, the height D of the convex portion of the barrier layer, and the height E of the convex portion of the second electrode are compared, and the barrier layer, And, the followability of the surface of the second electrode [(height of the convex portion of the barrier layer D-height of the convex portion of the uneven layer A) / (height A of the convex portion of the uneven layer)] × 100 (%). , [(Height E of the convex portion of the second electrode-Height A of the convex portion of the concave-convex layer) / (Height A of the convex portion of the concave-convex layer)] × 100 (%) was obtained.

[Preservation: Evaluation of Ca method for barrier layer]
For the barrier layers of the prepared samples 105 to 119, Ca method evaluation samples (types evaluated by permeation concentration) were prepared by the following method. Then, each of the prepared evaluation samples was stored in a 25 ± 0.5 ° C. 90 ± 2% RH environment, and the corrosion rate of Ca was observed at regular intervals. Observation and transmission concentration measurement (average of any 4 points) were performed every 1 hour, 5 hours, 10 hours, 20 hours, and every 20 hours thereafter, and the measured transmission concentration was less than 50% of the initial transmission concentration value. The observation time at the time point was used as an index of the storage stability of the organic EL element, and the evaluation was made according to the following criteria.
5: 400 hours or more 4: 300 hours or more and less than 400 hours 3: 200 hours or more and less than 300 hours 2: 100 hours or more and less than 200 hours 1: less than 100 hours

(Ca method evaluation sample)
In the preparation of each sample 105 to 119, the samples prepared up to the barrier layer were prepared. Then, after UV-cleaning the surface of the barrier layer of each sample, a thermosetting sheet-like adhesive (epoxy resin) was bonded to the barrier layer surface as a sealing resin layer with a thickness of 20 μm. After punching this into a size of 50 mm × 50 mm, it was placed in a glove box and dried for 24 hours.

Next, one side of a 50 mm × 50 mm size non-alkali glass plate (thickness 0.7 mm) was UV-cleaned. Then, using a vacuum vapor deposition apparatus manufactured by ALS Technology Co., Ltd., Ca was vapor-deposited in the center of the glass plate in a size of 20 mm × 20 mm via a mask. The thickness of Ca was 80 nm. Further, the Ca-deposited glass plate was transferred into the glove box, arranged so that the sealing resin layer surface of the barrier film and the Ca-deposited surface of the glass plate were in contact with each other, and bonded by vacuum lamination. At this time, heating was performed at 110 ° C. Further, the adhered sample was placed on a hot plate set at 110 ° C. with the glass plate facing down and cured for 30 minutes to prepare a cell for evaluation of the Ca method.

[Luminous efficiency]
Each of the prepared samples 101 to 119 was lit at room temperature (25 ° C.) under a constant current density condition of 2.5 mA / cm ² , and the spectral radiance meter CS-2000 (manufactured by Konica Minolta) was lit. The radiance of each sample was measured using the above, and the luminous efficiency (L) at the current value was determined.
The luminous efficiency is expressed as a relative value with the luminous efficiency of the sample 101 as 100, based on the light extraction efficiency of the organic EL element of the sample 101.

[Preservation]
(Preservation test)
The organic EL elements of each sample 101 to 119 are wound around a plastic roller having a curvature of 6 mmφ so that the organic EL element forming surface is on the outside, and stored for 500 hours in an environment of 85 ° C. and 85% RH. did.

(Change in luminous efficiency)
Then, the luminous efficiency of the sample after storage was determined by the same method as described above, the difference in luminous efficiency (ΔL) between before and after storage was determined, and the relative value was evaluated with the value before storage as 100%.

(Change in drive voltage)
Further, in the organic EL element of each sample before and after storage, the voltage when the front luminance on the resin substrate side was 1000 cd / m ² was measured as the drive voltage (V). Then, the difference (ΔV) in the drive voltage from that before storage was obtained. A spectral radiance meter CS-2000 (manufactured by Konica Minolta Sensing) was used to measure the brightness.

(Dark spot)
A current of 1 mA / cm ² was applied to the organic EL element of each sample after storage to cause light emission. Next, a part of the light emitting part of the organic EL element was magnified and photographed with a 100x optical microscope (MS-804 manufactured by Moritex, lens MP-ZE25-200). Next, the photographed image was cut out in 2 mm squares, and the presence or absence of dark spots was observed for each image. From the observation results, the ratio of the dark spot generation area to the light emission area was obtained, and the dark spot resistance was evaluated according to the following criteria.

5: No dark spots are observed 4: Dark spots are 0.1% or more and less than 1.0% 3: Dark spots are 1.0% or more and 3. Less than 0% 2: Dark spot occurrence area is 3.0% or more and less than 6.0% 1: Dark spot occurrence area is 6.0% or more

Table 1 shows the configurations of the uneven layer, the barrier layer, and the first electrode for the organic EL element of each sample, and the evaluation results of the storage stability, the luminous efficiency, and the stability of each sample.

As shown in Table 1, the samples 105 to 119 having the uneven layer have improved luminous efficiency as compared with the samples 101 to 104 having no uneven layer, except for the sample 118. In the sample 118, since the barrier layer is formed on the uneven layer by the coating method, the uneven shape due to the uneven layer is flattened. That is, the surface of the layer above the barrier layer is not formed in a shape that follows the uneven structure of the surface of the uneven layer. Therefore, the organic EL element has a concavo-convex layer, and further, the layer above the barrier layer follows the concavo-convex structure on the surface of the concavo-convex layer, so that the efficiency of extracting light emitted from the light emitting layer is improved. Luminous efficiency is improved.

On the other hand, in the above-mentioned organic EL elements of Samples 106 to 117 and Samples 119 having improved luminous efficiency, Sample 119 having an organic layer made of α-NPD has a higher shelf life than Samples 107 to 117 having a barrier layer. After the test, the luminous efficiency drops significantly, the drive voltage rises significantly, and dark spots occur significantly. This indicates that the organic layer alone such as α-NPD cannot obtain sufficient barrier performance, and the organic EL element is damaged by outgas, moisture, etc. from the uneven layer. Therefore, by forming a barrier layer on the uneven layer using a silicon compound as in Samples 107 to 117, outgas and moisture from the uneven layer can be blocked, and the reliability of the organic EL element is improved. ..

Comparing Sample 107 and Samples 109 to 111, which differ only in the materials constituting the first electrode, the luminous efficiency of Sample 107 using IZO as the first electrode is the highest, and each evaluation after storage is also high. Therefore, by forming the first electrode on the barrier layer using IZO, the luminous efficiency and reliability of the organic EL element can be further improved.

Comparing Samples 105 to 107 and Samples 112 to 117, which differ only in the average thickness of the uneven layer, the luminous efficiency of the sample 107 having an average thickness of 2000 nm is the highest, and the luminous efficiency of the sample 113 having an average thickness of 1500 nm is the highest. Is the next highest. In addition, the samples 107 and 113 are highly evaluated after storage. Further, in the sample 105 having an average thickness of the uneven layer of 50 nm, the evaluation of the luminous efficiency is significantly lower than that of the sample 117 having an average thickness of the uneven layer of 100 nm. Further, even in the sample 106 having an average thickness of 3000 nm, the luminous efficiency and each evaluation after storage are significantly lower than those of the sample 112 having an average thickness of 2500 nm.
Therefore, by setting the average thickness of the uneven layer to 100 nm or more and 2500 nm or less, it is possible to achieve both the luminous efficiency and reliability of the organic EL element.

In the organic EL device having the same configuration as the sample 107, an organic EL device manufactured by setting the height of the convex portion of the uneven layer to less than 10 nm or making the height of the convex portion of the concave-convex layer larger than 100 nm is sufficient. No improvement in efficiency was expected. Further, even in an organic EL device in which the pitch of the convex portion of the concave-convex layer is less than 100 nm or the pitch of the convex portion of the concave-convex layer is larger than 1000 nm, sufficient efficiency improvement cannot be expected.

The present invention is not limited to the configuration described in the above-described embodiment, and various modifications and changes can be made without departing from the configuration of the present invention.

10 ... Organic EL element, 11 ... Base material, 12 ... Underlayer layer, 13 ... Concavo-convex layer, 13A ... Coating film, 14 ... Barrier layer, 15 ... First electrode , 16 ... Light emitting unit, 17 ... Second electrode, 18 ... Adhesive layer, 19 ... Sealing base material, 20 ... Mother mold

Claims (11)

With the base material
An uneven layer having an uneven structure on the surface and an average thickness of 100 nm or more and 2500 nm or less,
The barrier layer formed on the uneven layer and
The first electrode provided on the barrier layer and
The light emitting unit provided on the first electrode and
A second electrode provided on the light emitting unit is provided.
The height of the convex portion of the uneven layer is 10 nm or more and 1000 nm or less.
The thickness of the concave portion of the uneven layer is 10 nm or more and 2000 nm or less.
An organic electroluminescence device having a shape in which the surface of the barrier layer and the surface of the second electrode follow the concave-convex structure of the concave-convex layer. The organic electroluminescence device according to claim 1, wherein the pitch of the convex portions of the concave-convex layer is 100 nm or more and 2000 nm or less. The organic electroluminescence device according to claim 1, wherein the uneven layer is made of an organic substance. The organic electroluminescence device according to claim 1, wherein a base layer in contact with the uneven layer is provided between the base material and the uneven layer. The organic electroluminescence device according to claim 1, wherein the barrier layer contains a silicon compound. The organic electroluminescence element according to claim 1, wherein the barrier layer has a water vapor transmission rate (25 ± 0.5 ° C., relative humidity 90 ± ² % RH) of 0.001 g / (m 2.24 h) or less. The organic electroluminescence device according to claim 1, wherein at least one of the first electrode and the second electrode is formed of IZO. The organic electroluminescence device according to claim 1, wherein at least one of the first electrode and the second electrode contains silver as a main component. The process of forming a coating film containing a material for forming an uneven layer on a substrate, and
The uneven structure of the matrix is transferred to the coating film, and the average thickness is 100 nm or more and 2500 nm or less , the height of the convex portion is 10 nm or more and 1000 nm or less, and the thickness of the concave portion is 10 nm or more and 2000 nm or less. The process of forming the layer and
A step of forming a barrier layer on the uneven layer and
The step of forming the first electrode on the barrier layer and
The step of forming a light emitting unit on the first electrode and
It has a step of forming a second electrode on the light emitting unit.
The barrier layer to the second electrode are formed into a shape that follows the uneven structure of the uneven layer.
A method for manufacturing an organic electroluminescence device. The method for manufacturing an organic electroluminescence device according to claim 9 , wherein the barrier layer is formed by a dry process. The method for manufacturing an organic electroluminescence device according to claim 9 , further comprising a step of forming a base layer on a base material and a step of forming a coating film containing the uneven layer forming material on the base layer.

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