WO2012046741A1

WO2012046741A1 - Organic el device

Info

Publication number: WO2012046741A1
Application number: PCT/JP2011/072889
Authority: WO
Inventors: 小野　善伸
Original assignee: 住友化学株式会社
Priority date: 2010-10-08
Filing date: 2011-10-04
Publication date: 2012-04-12
Also published as: JP2012084307A; TW201232868A

Abstract

An organic EL device provided with an organic EL element, a first film disposed facing the organic EL element, and a light extraction structure having a light-exiting surface from which light emitted from the organic EL element exits. The first film is provided with a gas barrier layer containing a silicon atom, an oxygen atom, and a carbon atom. The silicon distribution curve, the oxygen distribution curve and the carbon distribution curve of the gas barrier layer satisfy the following conditions: (i) among the ratio of the number of silicon atoms, the ratio of the number of oxygen atoms and the ratio of the number of carbon atoms, the ratio of the number of silicon atoms is the second largest in a region accounting for 90 % or more in the thickness direction of the gas barrier layer; (ii) the carbon distribution curve has at least one extreme value; and (iii) the difference between the maximum value and the minimum value of the ratio of the number of carbon atoms is 5 atom % or more in the carbon distribution curve.

Description

Organic EL device

The present invention relates to an organic EL device, a lighting device, a planar light source, and a display device.

An organic EL (Electro Luminescence) element has a structure in which a plurality of thin films are stacked. Flexibility can be imparted to the element itself by appropriately setting the thickness and material of each thin film. When such an organic EL element is provided on a flexible film, the entire apparatus on which the organic EL element is mounted can be a flexible apparatus.

Since the organic EL element deteriorates when exposed to the outside air, it is usually provided on a film having a high gas barrier property that hardly permeates oxygen and moisture. As such a film having a high gas barrier property, a film formed by forming a thin film made of an inorganic oxide such as silicon oxide, silicon nitride, silicon oxynitride and aluminum oxide on a plastic substrate has been proposed.

As a method of forming a thin film made of an inorganic oxide on a plastic substrate, physical vapor deposition (PVD) such as vacuum deposition, sputtering, ion plating, vacuum chemical vapor deposition, plasma chemistry, etc. Chemical vapor deposition (CVD) such as vapor deposition is known. As a film having a high gas barrier property using such a film forming method, for example, Japanese Patent Laid-Open No. 4-89236 (Patent Document 1) discloses a laminated vapor deposition formed by laminating two or more silicon oxide vapor deposited films. A film having a membrane layer is disclosed.

On the other hand, a film having ceramic-based inorganic barrier films and polymer films laminated alternately is disclosed in JP-T-2002-532850 (Patent Document 2).

JP-A-4-89236 JP 2002-532850 A

However, the film described in Patent Document 1 has a problem that the gas barrier property is not always sufficient and the gas barrier property is lowered by being bent.

According to the film described in Patent Document 2, it is expected that the gas barrier property is improved and the decrease in the gas barrier property due to bending is suppressed. However, the film production process described in Patent Document 2 has a problem that it requires a complicated and long production time because the inorganic barrier film and the polymer film are alternately laminated.

As described above, the organic EL device needs to have a high gas barrier property and the like, but in addition to this, an organic EL element having higher light extraction efficiency is required.

An object of the present invention is to provide an organic EL device having a film that has a high gas barrier property, is hardly deteriorated by bending, and can be formed in a short time by a simple process.

A further object of the present invention is to provide an organic EL device with high light extraction efficiency.

The present invention has an organic EL element, a first film disposed opposite to the organic EL element, and an emission surface disposed opposite to the organic EL element to emit light emitted from the organic EL element. And an organic EL device including the light extraction structure. The first film has a gas barrier layer containing silicon (silicon atoms), oxygen (oxygen atoms), and carbon (carbon atoms). Ratio of silicon atom (number) to the total amount of silicon atoms, oxygen atoms and carbon atoms (silicon atomic ratio), ratio of oxygen atom (number) ratio (oxygen atomic ratio) and amount of carbon atoms (number) ) Ratio (carbon atomic ratio) and the distance from one surface of the gas barrier layer in the thickness direction (film thickness direction) of the gas barrier layer, a silicon distribution curve, an oxygen distribution curve, and a carbon distribution curve, respectively. Satisfies the following conditions (i) to (iii).
(I) In the region of 90% or more in the thickness direction (film thickness direction) of the gas barrier layer, the silicon atomic ratio is the second largest value among the silicon atomic ratio, oxygen atomic ratio, and carbon atomic ratio. is there.
(Ii) The carbon distribution curve has at least one extreme value.
(Iii) The difference between the maximum value and the minimum value of the atomic ratio of carbon in the carbon distribution curve is 5 atomic% (at%) or more.

Further, according to the present invention, both the front intensity and the integrated intensity of light incident on the light extraction structure from the surface opposite to the emission surface and emitted from the emission surface are flat. The present invention relates to an organic EL device in which the light emitting surface has a concavo-convex structure that is 1.3 times or more compared to the case. In other words, the light extraction structure has an intensity of light incident on the structure and emitted from the light extraction side surface, and the light extraction side surface of the virtual structure having a planar surface on the light extraction side. When compared with the intensity of light emitted from the surface, both the front intensity and the integrated intensity are 1.3 times or more.

In another aspect, the present invention relates to an illumination device, a surface light source device, and a display device having the organic EL device.

According to the present invention, it is possible to provide an organic EL device including a film that has a high gas barrier property, is unlikely to be deteriorated by bending, and can be formed in a short time by a simple process. Furthermore, according to the present invention, an organic EL device with high light extraction efficiency can be provided.

It is a figure which shows the organic electroluminescent apparatus which concerns on one Embodiment. It is a figure which shows the organic electroluminescent apparatus which concerns on one Embodiment. It is a conceptual diagram which shows one Embodiment of the apparatus for manufacturing an organic electroluminescent apparatus. It is a schematic diagram which shows one Embodiment of the apparatus which manufactures a 1st film. It is a figure which shows one Embodiment of a light extraction structure. It is a figure which shows the virtual structure 110 typically. It is a figure for demonstrating I ((theta)). It is a graph which shows the silicon distribution curve, oxygen distribution curve, and carbon distribution curve in the 1st film obtained by reference example A1. It is a graph which shows the silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve in the 1st film obtained by reference example A1. It is a graph which shows the silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve in the 1st film obtained by reference example A2. It is a graph which shows the silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve in the 1st film obtained by reference example A2. It is a graph which shows the silicon distribution curve, oxygen distribution curve, and carbon distribution curve in the 1st film obtained by reference example A3. It is a graph which shows the silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve in the 1st film obtained by reference example A3. It is a graph which shows the silicon distribution curve, oxygen distribution curve, and carbon distribution curve in the 1st film obtained by reference comparative example A1. It is a graph which shows the silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve in the 1st film obtained by reference comparative example A1. It is a microscope picture of the section of UTE12. It is a microscope picture of the surface of UTE12. It is a figure shown about the measuring method of I ((theta)). It is a microscope picture of the surface of UTE21. It is a microscope picture of the surface of WF80.

Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

The organic EL device according to the present embodiment is opposed to the organic EL element, the first film disposed to face the organic EL element, and the position where the light emitted from the organic EL element is emitted. And a light extraction structure having an emission surface from which the light is emitted.

The organic EL device is usually provided on a support substrate. The organic EL device may further include a sealing member that is bonded to the support substrate while interposing an organic EL element between the organic EL device and the support substrate. Even if the 1st film of the organic EL element which concerns on this embodiment is used as a support base material with which an organic EL element is provided, it may be used as a sealing member bonded with a support base material. Below, the organic EL element of the form which is further provided with a 2nd film as a support substrate and a 1st film is provided as a sealing member is demonstrated.

Organic EL elements mounted on organic EL devices can be roughly divided into the following three types of elements. That is, the organic EL element (I) emits light toward a support substrate on which the organic EL element is mounted, a so-called bottom emission type element, and (II) emits light toward the opposite side of the support substrate. And so-called top emission type elements, and (III) a dual emission type element that emits light toward the support substrate and emits light toward the opposite side of the support substrate. . The organic EL element mounted on the organic EL device according to this embodiment may be any type of element. Hereinafter, as an example, an organic EL device provided with a top emission type element will be described first with reference to FIG. 1, and then an organic EL device provided with a bottom emission type element will be described with reference to FIG. .

FIG. 1 is a cross-sectional view schematically showing the organic EL device of this embodiment. In the organic EL device 13 of the embodiment shown in FIG. 1, the organic EL element 2 is mounted on the second film 1. The first film 11 is disposed on the second film 1 while the organic EL element 2 is interposed between the first film 11 and the second film 1. The first film 11 seals the organic EL element 2 together with the second film 1. The 2nd film 1 and the 1st film 11 are bonded together via the contact bonding layer 4 provided between them. The organic EL device 13 may include a protective layer 3 that covers the organic EL element 2 and is interposed between the organic EL element 2 and the adhesive layer 4 as necessary. By providing this protective layer 3, the organic EL element 2 can be protected from the adhesive layer 4.

The organic EL device 13 further includes a light extraction structure 14. The light extraction structure 14 is disposed at a position where light emitted from the organic EL element 2 is emitted. The organic EL element 2 of this embodiment shown in FIG. 1 is a top emission type element, and emits light toward the first film 11. Therefore, the position where light is emitted to the outside of the organic EL device 13 is the outermost surface on the first film 11 side with respect to the organic EL element 2. Therefore, in the embodiment shown in FIG. 1, the light extraction structure 14 is provided in the outermost layer on the first film 11 side with respect to the organic EL element 2. The light extraction structure 14 has an emission surface S from which light is emitted.

The light extraction structure 14 may be formed directly on the first film 11, but in the present embodiment, the light extraction structure 14 is bonded to the first film 11 by the adhesive layer 15.

Although details of the light extraction structure 14 will be described later, by arranging the light extraction structure 14 at a position where the light is emitted, the light extraction efficiency is improved, and as a result, the light emission efficiency of the entire organic EL device is improved. To do.

Since the organic EL element 2 of the present embodiment is a top emission type element, the first film 11 and the light extraction structure 14 need to be formed of a member that transmits light. On the other hand, the second film 1 corresponding to the support substrate in the present embodiment may be formed of an opaque member that does not transmit light.

As the second film 1, a plastic film or a metal film can be used, and a metal film is preferable. Since the metal film has a higher gas barrier property than a plastic film or the like, the gas barrier property of the organic EL device can be improved. As the metal film, for example, a thin plate of Al, Cu or Fe and a thin plate of an alloy such as stainless steel can be used.

The first film 11 has a gas barrier layer 5 containing silicon atoms, oxygen atoms and carbon atoms. In this embodiment, the 1st film 11 is comprised from the base material 6 and the gas barrier layer 5 provided on the main surface by the side of the organic EL element 2 of the base material 6. FIG. The gas barrier layer 5 has high gas barrier properties by satisfying the conditions (i), (ii), and (iii) described later, and can further suppress a decrease in gas barrier properties when bent.

By sealing the organic EL element 2 with such a first film and a second film, a flexible organic EL device having sufficient durability and gas barrier properties can be realized. In particular, when a metal film is used as the second film 1, since both the second film 1 and the first film 11 exhibit high gas barrier properties, the organic EL device having higher durability and gas barrier properties. Can be realized.

FIG. 2 is a cross-sectional view schematically showing an organic EL device 13 according to another embodiment. The organic EL device 13 of the embodiment shown in FIG. 2 is different from the embodiment shown in FIG. 1 in the organic EL element 2 and the second film 1 and further in the position where the light extraction structure 14 is arranged.

In this embodiment, a bottom emission type organic EL element 2 is provided. Similar to the above-described embodiment, the light extraction structure 14 is disposed at a position where light emitted from the organic EL element 2 is emitted. Since the organic EL element 2 shown in FIG. 2 emits light toward the second film 1, the position where the light is emitted is the outermost surface on the second film 1 side with respect to the organic EL element 2. is there. Therefore, in the embodiment shown in FIG. 2, the light extraction structure 14 is provided in the outermost layer on the second film 1 side with respect to the organic EL element 2. The light extraction structure 14 is bonded to the second film 1 via the adhesive layer 15.

The organic EL element 2 of the present embodiment emits light toward the second film 1 corresponding to the support substrate. Therefore, the second film needs to be a film exhibiting light transmittance.

The second film 1 of the present embodiment is not particularly limited as long as it is a light-transmitting film, but contains silicon atoms, oxygen atoms, and carbon atoms in the same manner as the first film 11 from the viewpoint of gas barrier properties. The second gas barrier layer 8 is preferably provided. In the present embodiment, the second film 1 includes a base material 7 and a second gas barrier layer 8 provided on the main surface of the base material 7 on the organic EL element 2 side. Like the gas barrier layer 5 of the first film 11, the second gas barrier layer 8 has a high gas barrier property by satisfying conditions (i), (ii), and (iii) described later, and is further bent. It is possible to suppress a decrease in gas barrier properties when it is performed.

Also by sealing the organic EL element 2 with such a first film 1 and a second film, it is possible to realize an organic EL device that is flexible and has both sufficient durability and gas barrier properties.

In the organic EL device of the embodiment shown in FIG. 2, a double-sided light emitting organic EL element may be provided in place of the bottom emission organic EL element. In this case, a light extraction structure 14 may be further provided. That is, the light extraction structure 14 may be provided on the surface of the first film 11 opposite to the organic EL element 4.

The organic EL element may be sealed with the first film and the second film using the second film as a sealing member and the first film having a gas barrier layer as a supporting substrate.

For example, in the embodiment shown in FIGS. 1 and 2, an additional film may be further bonded to the first film and / or the second film. As an additional film, a protective film for protecting the surface of the organic EL device, an antireflection film for preventing reflection of external light incident on the organic EL device, an optical functional film for adjusting the phase and polarization of light, And the optical film etc. which have the structure by which the some film chosen from these was laminated | stacked are mentioned. The additional film is bonded to one side or both sides of the first film and / or the second film.

(Adhesive layer)
The adhesive layer 4 is a layer that adheres the first film and the second film in a state where the organic EL element is disposed between them. In the form in which the light extraction structure 14 is bonded to the first film 11 and / or the second film 1, the adhesive layer includes the light extraction structure 14 and the first film 11 and / or the second film 1. It can also be used as an adhesive layer 15 for adhering. The adhesive used for the adhesive layer preferably has a high gas barrier property. In the organic EL device in which the light emitted from the organic EL element 2 as shown in FIG. 1 is emitted to the outside through the adhesive layer 4, the light transmittance of the adhesive layer 4 is preferably high. In this case, from the viewpoint of light extraction efficiency, the absolute value of the difference in refractive index between the layer in contact with the adhesive layer 4 and the adhesive layer 4 is preferably small.

As the adhesive that can be used for the adhesive layer, a curable adhesive such as a thermosetting adhesive and a photocurable adhesive is suitable.

Examples of thermosetting resin adhesives include epoxy adhesives and acrylate adhesives.

Examples of the epoxy adhesive include an adhesive containing an epoxy compound selected from bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenoxy resin.

As the acrylate adhesive, for example, a monomer as a main component selected from acrylic acid, methacrylic acid, ethyl acrylate, butyl acrylate, 2-hexyl acrylate, acrylamide, acrylonitrile, hydroxyl acrylate, and the like, and copolymerizable with the main component And an adhesive containing a simple monomer.

Examples of the photo-curable adhesive include radical adhesives and cationic adhesives.

Examples of radical adhesives include adhesives containing epoxy acrylate, ester acrylate, ester acrylate, and the like.

Examples of cationic adhesives include adhesives containing epoxy resins, vinyl ether resins, and the like.

(Protective layer)
The protective layer is provided so as to cover the organic EL element. By providing this protective layer, the organic EL element can be protected from the adhesive layer.

Since the electron injection layer and the cathode constituting the organic EL element usually contain a material that is unstable in the atmosphere as a main component, after forming the organic EL element, the first film is pasted to the organic EL element. There is a possibility that the electron injection layer and the cathode may be deteriorated by moisture, oxygen, etc. in the atmosphere before being sealed. Therefore, the protective layer preferably has a function of blocking moisture and oxygen in the atmosphere and protecting the organic EL element from these until the organic EL element is sealed by the first film.

Examples of the material used for the protective layer include metal materials that are stable in the atmosphere, inorganic insulating materials and organic insulating materials having excellent barrier properties, and the like. The metal material is selected from, for example, Al, Cu, Ag, Au, Pt, Ti, Cr, Co, and Ni. Inorganic insulating material, for _example, SiO 2, SiN, selected from _SiO x _{N y,} and _SiO x _{C y.} Parylene or the like is used as the organic insulating material.

The protective layer formed from a metal material is formed by, for example, a vacuum deposition method, a sputtering method, or a plating method. The protective layer formed from an inorganic insulating material is formed by, for example, a sputtering method, a CVD method, or a laser ablation method. The protective layer formed of an organic insulating material is formed by, for example, a film forming method including vacuum vapor deposition of a monomer gas and polymerization on a vapor deposition film (coating surface) containing the monomer.

(Method for manufacturing organic EL device)
Hereinafter, a method for manufacturing the organic EL device will be described with reference to FIG. FIG. 3 is a diagram schematically showing an apparatus for manufacturing an organic EL device. In the apparatus shown in FIG. 3, the second film 1 and the first film 11 are bonded together, and the light extraction structure 14 is further bonded to the first film 11. On the second film 1, an organic EL element is formed in advance.

The unwinding roll 500 sends out the 2nd film 1 in which the organic EL element was previously formed on it. The unwinding roll 510 sends out the first film 11. On the 2nd film 1 sent out from the unwinding roll 500, the adhesive agent is apply | coated by the coating device 610 for 1st contact bonding layers, and a 1st contact bonding layer is formed. Thereafter, the first bonding rolls 511 and 512 are used to bond the second film 1 and the first film 11 supplied via the transport roll 513 via the first adhesive layer, and further for the first adhesive layer. The first adhesive layer is cured (solidified) by the curing device 611.

On the first film 11, an adhesive is applied by a second adhesive layer coating device 620 provided on the downstream side of the curing device 611, and a second adhesive layer is further formed. Subsequently, the second bonding rolls 521 and 522 cause the first film 11 and the light extraction structure 14 fed from the unwinding roll 520 and supplied via the transporting roll 523 to pass through the second adhesive layer. Further, the second adhesive layer is cured (solidified) by the curing device 621 for the second adhesive layer. Thereafter, the formed organic EL device is wound up by a winding roll 530.

When three or more films are bonded, the order of bonding is appropriately changed according to the stacking order of the organic EL devices.

(First film)
Next, the first film 11 will be described. One of the features of the organic EL device of the present embodiment is the first film, particularly the gas barrier layer 5 thereof.

The first film has a gas barrier layer containing silicon atoms, oxygen atoms, and carbon atoms. The ratio of the number of silicon atoms (the atomic ratio of silicon), the ratio of the number (quantity) of oxygen atoms (the atomic ratio of oxygen) and the ratio of the number of carbon atoms (carbon) to the total amount of silicon atoms, oxygen atoms and carbon atoms The atomic distribution of the gas barrier layer is measured while changing the distance from one surface of the gas barrier layer in the thickness direction of the gas barrier layer, thereby expressing the relationship between the atomic ratio of each atom and the distance from the surface of the gas barrier layer. Curves, oxygen distribution curves and carbon distribution curves can be obtained. These curves obtained from the gas barrier layer according to the present embodiment satisfy the following conditions (i), (ii), and (iii).
(I) In the region of 90% or more in the thickness direction of the gas barrier layer, the silicon atomic ratio is the second largest value among the silicon atomic ratio, oxygen atomic ratio, and carbon atomic ratio.
(Ii) The carbon distribution curve has at least one extreme value.
(Iii) The difference (absolute value) between the maximum value and the minimum value of the atomic ratio of carbon in the carbon distribution curve is 5 at% or more.

In other words, the condition (i) means that the following formula (1) or the following formula (2) is satisfied in a region of 90% or more in the thickness direction of the gas barrier layer.
(Atomic ratio of oxygen)> (atomic ratio of silicon)> (atomic ratio of carbon) (1)
(Atomic ratio of carbon)> (Atomic ratio of silicon)> (Atomic ratio of oxygen) (2)

<Base material of first film>
The gas barrier layer described above is usually formed on a substrate. That is, the first film includes a base material and a gas barrier layer formed on the base material. Examples of the base material of the first film include a colorless and transparent resin film or resin sheet. Examples of the resin used for such a substrate include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin resins such as polyethylene (PE), polypropylene (PP), and cyclic polyolefin; Resin; Polycarbonate resin; Polystyrene resin; Polyvinyl alcohol resin; Saponified ethylene-vinyl acetate copolymer; Polyacrylonitrile resin; Acetal resin; and Polyimide resin. Among these resins, polyester-based resins and polyolefin-based resins are preferable, and PET and PEN are particularly preferable from the viewpoint of high heat resistance, low coefficient of linear expansion, and low manufacturing cost. These resin may be used individually by 1 type, and may be used in combination of 2 or more type.

The thickness of the base material of the first film can be appropriately set in consideration of the stability when the first film is manufactured. The thickness of the substrate of the first film is preferably in the range of 5 to 500 μm from the viewpoint that the film can be conveyed even in a vacuum. When the gas barrier layer is formed by the plasma CVD method, since the gas barrier layer is formed while discharging through the base material of the second film, the thickness of the base material of the first film is more preferably 50 to 200 μm. Preferably, the thickness is 50 to 100 μm.

It is preferable to subject the first film substrate to a surface activation treatment for cleaning the surface from the viewpoint of adhesion to a gas barrier layer described later. Examples of such surface activation treatment include corona treatment, plasma treatment, and flame treatment.

<Gas barrier layer>
The gas barrier layer is formed on at least one side of the substrate. The first film according to this embodiment may include at least one gas barrier layer containing silicon atoms, oxygen atoms, and carbon atoms and satisfying all of the above conditions (i) to (iii). For example, the first film may have another layer that does not satisfy at least one of the above conditions (i) to (iii). The gas barrier layer or other layer may further contain nitrogen atoms, aluminum atoms, and the like.

When the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon do not satisfy the condition (i), the gas barrier property of the first film is lowered. It is preferable that the region satisfying the above formula (1) or (2) occupies 90% or more of the thickness of the gas barrier layer. This ratio is more preferably 95% or more, and still more preferably 100%.

In the gas barrier layer according to this embodiment, the carbon distribution curve needs to have at least one extreme value as the condition (ii). In such a gas barrier layer, the carbon distribution curve preferably has two extreme values, and more preferably has three or more extreme values. When the carbon distribution curve does not have an extreme value, the gas barrier property is lowered when the obtained first film is bent. When the carbon distribution curve has at least three extreme values, the distance in the thickness direction between adjacent extreme values of the carbon distribution curve is preferably 200 nm or less, and more preferably 100 nm or less.

In this specification, the extreme value means a maximum value or a minimum value in a distribution curve obtained by plotting an atomic ratio of an element with respect to a distance from the surface of the gas barrier layer in the thickness direction of the gas barrier layer. In the above distribution curve, the maximum value is a point where the value of the atomic ratio of the element changes from increasing to decreasing with the change of the distance from the surface of the gas barrier layer, and the value of the atomic ratio of the element at that point In comparison, the atomic ratio of the element at the point where the value of the atomic ratio of the element at the position where the distance from the surface of the gas barrier layer in the thickness direction of the gas barrier layer from this point is further changed by 20 nm decreases by 3 at% or more. . The minimum value is a point where the value of the atomic ratio of the element changes from decreasing to increasing as the distance from the surface of the gas barrier layer changes, and compared with the value of the atomic ratio of the element at that point, The atomic ratio of the element at the point where the value of the atomic ratio of the element at a position where the distance from the surface in the thickness direction of the gas barrier layer from the point is further changed by 20 nm further increases by 3 at% or more.

The gas barrier layer according to the present embodiment requires that the difference between the maximum value and the minimum value of the atomic ratio of carbon in the carbon distribution curve is 5 at% or more as the condition (iii). In such a gas barrier layer, the difference between the maximum value and the minimum value of the atomic ratio of carbon is more preferably 6 at% or more, and further preferably 7 at% or more. If this difference is less than 5 at%, the gas barrier property of the first film is lowered when the first film is bent. The upper limit of the difference is not particularly limited, but is usually about 30 at%.

(Oxygen distribution curve, extreme value)
The oxygen distribution curve of the gas barrier layer preferably has at least one extreme value, more preferably has at least two extreme values, and more preferably has at least three extreme values. When the oxygen distribution curve has an extreme value, the gas barrier property tends to be less likely to occur due to the bending of the first film. When the oxygen distribution of the gas barrier layer has at least three extreme values, the gas barrier layer in the thickness direction of each gas barrier layer between one extreme value of the oxygen distribution curve and the extreme value adjacent to the extreme value. The difference in distance from the surface is preferably 200 nm or less, and more preferably 100 nm or less.

(Oxygen distribution curve, difference between maximum and minimum values)
The difference between the maximum value and the minimum value of the oxygen atomic ratio in the oxygen distribution curve of the gas barrier layer is preferably 5 at% or more, more preferably 6 at% or more, and even more preferably 7 at% or more. If this difference is equal to or greater than the lower limit, the gas barrier property tends to be less likely to occur due to the bending of the first film. The upper limit of this difference is not particularly limited, but is usually about 30 at%.

The difference between the maximum value and the minimum value of the atomic ratio of silicon in the silicon distribution curve of the gas barrier layer is preferably less than 5 at%, more preferably less than 4 at%, and even more preferably less than 3 at%. If this difference is less than the upper limit, the gas barrier property of the first film tends to be particularly high.

(Oxygen carbon distribution curve, difference between maximum and minimum values)
Expresses the relationship between the distance from the surface of the gas barrier layer in the thickness direction and the ratio of the total amount of oxygen atoms and carbon atoms to the total amount of silicon atoms, oxygen atoms, and carbon atoms (atomic ratio of oxygen and carbon) In the oxygen-carbon distribution curve, the difference between the maximum value and the minimum value of the total atomic ratio of oxygen and carbon is preferably less than 5 at%, more preferably less than 4 at%, and more preferably less than 3 at%. Further preferred. If this difference is less than the upper limit, the gas barrier property of the first film tends to be particularly high.

The silicon distribution curve, oxygen distribution curve, carbon distribution curve, and oxygen carbon distribution curve are obtained by combining X-ray photoelectron spectroscopy (XPS) measurement with rare gas ion sputtering such as argon. It can be created by so-called XPS depth profile measurement in which surface composition analysis is sequentially performed while being exposed. A distribution curve obtained by such XPS depth profile measurement can be created, for example, with the vertical axis as the atomic ratio (unit: at%) of each element and the horizontal axis as the etching time (sputtering time). The etching time generally correlates with the distance from the surface of the gas barrier layer in the thickness direction of the gas barrier layer. Therefore, the “distance from one surface of the gas barrier layer in the thickness direction of the gas barrier layer” is the distance from the surface of the gas barrier layer calculated from the relationship between the etching rate and the etching time employed in the XPS depth profile measurement. Can be adopted. In such XPS depth profile sputtering employing for the measurement, an argon (Ar ⁺⁾ rare gas ions sputter method using the adopted as an etching ion species, the etching rate (etching rate) was 0.05 nm / sec ( It is preferable to set the value in terms of SiO ₂ thermal oxide film.

From the viewpoint of forming a gas barrier layer having a uniform and excellent gas barrier property over the entire film surface, the gas barrier layer is substantially uniform in the film surface direction (direction parallel to the main surface (surface) of the gas barrier layer). Preferably there is. In this specification, “the gas barrier layer is substantially uniform in the film surface direction” means that an oxygen distribution curve and a carbon distribution curve are measured at any two measurement points on the film surface of the gas barrier layer by XPS depth profile measurement. When the oxygen carbon distribution curve is created, the number of extreme values of the carbon distribution curve obtained at any two measurement points is the same, and the maximum value of the carbon atomic ratio in each carbon distribution curve The difference from the minimum value is the same as each other, or the difference is within 5 at%.

The carbon distribution curve is preferably substantially continuous. In the present specification, “the carbon distribution curve is substantially continuous” means that a portion in which the atomic ratio of carbon in the carbon distribution curve changes discontinuously is not included. Specifically, this is because the distance (x, unit: nm) from the surface of the gas barrier layer in the thickness direction calculated from the etching rate and etching time, and the atomic ratio of carbon (c, unit: at). %) In relation to the following formula (F1):
−1.0 ≦ (dc / dx) ≦ 1.0 (F1)
It means that the condition represented by is satisfied.

The first film according to the present embodiment only needs to include at least one gas barrier layer that satisfies all of the above conditions (i) to (iii), and the first film has the above conditions (i) to (iii). Two or more gas barrier layers satisfying all of the above may be provided. When the first film includes two or more such gas barrier layers, the materials of the plurality of gas barrier layers may be the same or different. Further, when the first film includes two or more such gas barrier layers, the gas barrier layers may be formed on one surface of the base material, and are respectively formed on both surfaces of the base material. It may be formed. The first film may include a thin film layer that does not necessarily have gas barrier properties.

In the silicon distribution curve, oxygen distribution curve, and carbon distribution curve, when the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon satisfy the condition expressed by the formula (1), the silicon atoms and oxygen in the gas barrier layer The atomic ratio of the silicon atom content to the total amount of atoms and carbon atoms is preferably 25 to 45 at%, more preferably 30 to 40 at%. The atomic ratio of the oxygen atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer is preferably 33 to 67 at%, more preferably 45 to 67 at%. The atomic ratio of the carbon atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer is preferably 3 to 33 at%, and more preferably 3 to 25 at%.

In the silicon distribution curve, oxygen distribution curve, and carbon distribution curve, when the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon satisfy the condition expressed by the above formula (2), silicon in the gas barrier layer The atomic ratio of the content of silicon atoms with respect to the total amount of atoms, oxygen atoms and carbon atoms is preferably 25 to 45 at%, more preferably 30 to 40 at%. The atomic ratio of the oxygen atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer is preferably 1 to 33 at%, and more preferably 10 to 27 at%. The atomic ratio of the carbon atom content to the total amount of silicon atoms, oxygen atoms and carbon atoms in the gas barrier layer is preferably 33 to 66 at%, and more preferably 40 to 57 at%.

The thickness of the gas barrier layer is preferably 5 to 3000 nm, more preferably 10 to 2000 nm, and particularly preferably 100 to 1000 nm. When the thickness of the gas barrier layer is within these numerical ranges, more excellent gas barrier properties such as oxygen gas barrier properties and water vapor barrier properties can be obtained, and a decrease in gas barrier properties due to bending tends to be more effectively suppressed.

When the first film includes a plurality of gas barrier layers, the total thickness of these gas barrier layers is usually 10 to 10,000 nm, preferably 10 to 5000 nm, more preferably 100 to 3000 nm. More preferably, the thickness is 200 to 2000 nm. When the total thickness of the gas barrier layer is within these numerical ranges, more excellent gas barrier properties such as oxygen gas barrier properties and water vapor barrier properties can be obtained, and a decrease in gas barrier properties due to bending tends to be more effectively suppressed. is there.

The first film may further include a primer coat layer, a heat-sealable resin layer, an adhesive layer, and the like, if necessary, in addition to the base material of the first film and the gas barrier layer. The primer coat layer can be formed using a primer coat agent capable of improving the adhesion between the substrate and the gas barrier layer. The heat-sealable resin layer can be appropriately formed using a known heat-sealable resin. The adhesive layer can be appropriately formed using a normal adhesive, and the plurality of first films may be bonded to each other by such an adhesive layer.

The gas barrier layer of the first film is preferably a layer formed by a plasma chemical vapor deposition method. The gas barrier layer formed by plasma chemical vapor deposition is a plasma chemical vapor phase in which a second film substrate is disposed on a pair of film forming rolls, and plasma is generated by discharging between the pair of film forming rolls. A layer formed by a growth method is more preferable. When discharging between the pair of film forming rolls, it is preferable to reverse the polarity of the pair of film forming rolls alternately. The film forming gas used for such plasma chemical vapor deposition preferably includes an organosilicon compound and oxygen. The oxygen content in the film forming gas is preferably less than or equal to the theoretical oxygen amount necessary for complete oxidation of the entire amount of the organosilicon compound in the film forming gas. The gas barrier layer of the first film is preferably a layer formed by a continuous film forming process. Details of a method for forming a gas barrier layer using such a plasma chemical vapor deposition method will be described in a method for producing a first film described later.

<Method for producing first film>
Next, a method for producing the first film will be described. The first film can be produced by forming a gas barrier layer on the surface of the substrate of the first film. As a method for forming the gas barrier layer on the surface of the substrate of the first film, plasma chemical vapor deposition (plasma CVD) is preferable from the viewpoint of gas barrier properties. This plasma chemical vapor deposition method may be a plasma chemical vapor deposition method using a Penning discharge plasma method.

When generating plasma in the plasma enhanced chemical vapor deposition method, it is preferable to generate a plasma discharge in a space between a plurality of film forming rolls, using a pair of film forming rolls, and each of the pair of film forming rolls. More preferably, a substrate is disposed on the substrate, and plasma is generated by discharging between the pair of film forming rolls. By using a pair of film forming rolls in this manner, a base material existing on the other film forming roll while forming a gas barrier layer on the base material existing on one film forming roll during film formation. A gas barrier layer can be simultaneously formed on the upper layer. Thereby, not only the gas barrier layer can be efficiently produced, but also a film having the same structure can be simultaneously formed at a double film formation rate. As a result, it is possible to at least double the extreme value in the carbon distribution curve and efficiently form a gas barrier layer that satisfies all the above conditions (i) to (iii). From the viewpoint of productivity, it is preferable to form a gas barrier layer on the surface of the substrate of the first film by a roll-to-roll method. An apparatus that can be used for manufacturing the second film by such a plasma chemical vapor deposition method is not particularly limited, but includes at least a pair of film forming rolls and a plasma power source, and includes the pair of components. An apparatus capable of discharging between the film rolls is preferable. For example, by using the manufacturing apparatus shown in FIG. 4, it is possible to manufacture the first film by the roll-to-roll method while using the plasma chemical vapor deposition method.

Hereinafter, the method for producing the first film will be described in more detail with reference to FIG. FIG. 4 is a schematic diagram illustrating an example of a manufacturing apparatus that can be suitably used to manufacture the first film according to the present embodiment. In the following description and drawings, the same or corresponding elements are denoted by the same reference numerals, and overlapping descriptions are omitted as appropriate.

The manufacturing apparatus shown in FIG. 4 includes a feed roll 701, transport rolls 21, 22, 23, and 24, a pair of

film forming rolls

31 and 32 disposed opposite to each other, a gas supply pipe 41, and a plasma generation power source. 51,

magnetic field generators

61 and 62 installed inside the

film forming rolls

31 and 32, and a winding roll 702. In this manufacturing apparatus, at least the

film forming rolls

31 and 32, the gas supply pipe 41, the plasma generation power source 51, and the

magnetic field generators

61 and 62 are disposed in a vacuum chamber (not shown). . This vacuum chamber is connected to a vacuum pump (not shown), and the pressure in the vacuum chamber can be appropriately adjusted by such a vacuum pump.

In the manufacturing apparatus of FIG. 4, each film forming roll has a plasma generating power source so that the pair of film forming rolls (film forming roll 31 and film forming roll 32) can function as a pair of counter electrodes. 51 is connected. By supplying electric power from the plasma generating power source 51, a discharge is generated in the space between the film forming roll 31 and the film forming roll 32, and thereby plasma is generated in the space between the film forming roll 31 and the film forming roll 32. Can be generated. When the film-forming roll 31 and the film-forming roll 32 are also used as electrodes, the material and design may be changed as appropriate so that they can also be used as electrodes. The pair of film forming rolls (film forming rolls 31 and 32) are preferably arranged so that their central axes are substantially parallel on the same plane. In this way, a pair of film-forming rolls (film-forming rolls 31 and 32) are arranged, and a gas barrier layer is formed on each film-forming roll, so that a film is formed on one film-forming roll. Thus, the film formation rate can be doubled. In addition, since the films having the same structure can be stacked, it is possible to at least double the number of extreme values in the carbon distribution curve. According to such a manufacturing apparatus, it is possible to form a gas barrier layer on the surface of the substrate 6 by the CVD method, and while depositing a film component on the surface of the substrate 6 on the film forming roll 31, Furthermore, film components can also be deposited on the surface of the substrate 6 on the film forming roll 32. Therefore, the gas barrier layer can be efficiently formed on the surface of the substrate 6.

Inside the film forming roll 31 and the film forming roll 32,

magnetic field generators

61 and 62 are provided. The

magnetic field generators

61 and 62 are fixed so as not to rotate even if the film forming roll rotates.

As the film forming roll 31 and the film forming roll 32, normal rolls can be appropriately used. The diameters of the

film forming rolls

31 and 32 are preferably substantially the same from the viewpoint of forming a thin film more efficiently. The diameters of the

film forming rolls

31 and 32 are preferably 5 to 100 cm from the viewpoint of discharge conditions, chamber space, and the like.

4, the base material 6 is disposed on a pair of film forming rolls (the film forming roll 31 and the film forming roll 32) so that the surfaces of the base material 6 face each other. By disposing the base material 6 in this way, each of the base materials 6 existing between the pair of film forming rolls is generated when the plasma is generated by performing discharge between the film forming roll 31 and the film forming roll 32. It is possible to form films on the surfaces simultaneously. That is, according to such a manufacturing apparatus, a film component is deposited on the surface of the substrate 6 on the film forming roll 31 and a film component is further deposited on the film forming roll 32 by the CVD method. it can. Therefore, the gas barrier layer can be efficiently formed on the surface of the substrate 6.

As the delivery roll 701 and the transport rolls 21, 22, 23, 24, normal rolls can be used as appropriate. The winding roll 702 is not particularly limited as long as it can wind the substrate 6 on which the gas barrier layer is formed, and is appropriately selected from commonly used rolls.

The gas supply pipe 41 only needs to be able to supply or discharge the raw material gas or the like at a predetermined speed. As the plasma generating power source 51, a power source of a normal plasma generating apparatus can be used as appropriate. The plasma generating power supply 51 supplies power to the film forming roll 31 and the film forming roll 32 connected to the power supply 51, and makes it possible to use these as counter electrodes for discharge. As the plasma generating power source 51, since it is possible to perform plasma CVD more efficiently, a power source (such as an AC power source) that can alternately reverse the polarity of a pair of film forming rolls is used. Is preferred. More preferably, the plasma generation power source 51 can set the applied power to 100 W to 10 kW and the AC frequency to 50 Hz to 500 kHz in order to perform plasma CVD more efficiently. As the

magnetic field generators

61 and 62, normal magnetic field generators can be used as appropriate. As the base material 6, in addition to the base material of the first film, a film having a gas barrier layer formed in advance can be used. Thus, by using a film having a gas barrier layer formed in advance as the substrate 6, it is possible to increase the thickness of the gas barrier layer.

Using the manufacturing apparatus shown in FIG. 4, for example, by appropriately adjusting the type of source gas, the power of the electrode drum of the plasma generator, the pressure in the vacuum chamber, the diameter of the film forming roll, and the film transport speed A first film can be produced.

By using the manufacturing apparatus shown in FIG. 4 to generate a discharge between a pair of film forming rolls (film forming rolls 31 and 32) while supplying a film forming gas (such as a raw material gas) into the vacuum chamber, The film gas (source gas or the like) is decomposed by plasma, and a gas barrier layer is formed on the surface of the substrate 6 on the film forming roll 31 and on the surface of the substrate 6 on the film forming roll 32 by the plasma CVD method. . In such film formation, the base material 6 is conveyed by the delivery roll 701, the film formation roll 31 and the like, respectively. Therefore, a gas barrier is formed on the surface of the base material 6 by a roll-to-roll continuous film formation process. A layer is formed.

The source gas in the film forming gas used for forming the gas barrier layer is appropriately selected according to the material of the gas barrier layer to be formed. As the source gas, for example, an organosilicon compound containing silicon can be used. The source gas may contain monosilane as a silicon source in addition to the organosilicon compound.

The source gas is, for example, hexamethyldisiloxane, 1,1,3,3-tetramethyldisiloxane, vinyltrimethylsilane, methyltrimethylsilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, At least one organosilicon compound selected from the group consisting of phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and octamethylcyclotetrasiloxane including. Among these organosilicon compounds, hexamethyldisiloxane and 1,1,3,3-tetramethyldisiloxane are preferable from the viewpoints of handling properties of the compound and gas barrier properties of the resulting gas barrier layer. These organosilicon compounds can be used individually by 1 type or in combination of 2 or more types.

The film forming gas may contain a reactive gas in addition to the source gas. As this reaction gas, a gas that reacts with the raw material gas to form an inorganic compound such as oxide or nitride can be appropriately selected and used. As a reaction gas for forming an oxide, for example, oxygen or ozone can be used. As the reaction gas for forming the nitride, for example, nitrogen or ammonia can be used. These reaction gases are used alone or in combination of two or more. For example, when oxynitride is formed, a reaction gas for forming an oxide and a reaction gas for forming a nitride can be combined.

As a film forming gas, a carrier gas may be used as necessary in order to supply a source gas into the vacuum chamber. As the film forming gas, a discharge gas may be used as necessary in order to generate plasma discharge. As such a carrier gas and a discharge gas, known ones can be used as appropriate. For example, a rare gas such as helium, argon, neon, and xenon, or hydrogen can be used as the carrier gas or the discharge gas.

When the deposition gas contains a source gas and a reactive gas, the ratio of the source gas and the reactive gas is greater than the ratio of the amount of the reactive gas that is theoretically necessary to completely react the source gas and the reactive gas. However, it is preferable not to make the ratio of the reaction gas excessive. By appropriately controlling the ratio of the reaction gas, a thin film (gas barrier layer) satisfying all the above conditions (i) to (iii) can be formed particularly efficiently. When the deposition gas contains an organosilicon compound and oxygen, the amount of oxygen in the deposition gas is less than or equal to the theoretical oxygen amount required to fully oxidize the entire amount of the organosilicon compound in the deposition gas. Is preferred.

Hereinafter, a gas containing hexamethyldisiloxane (organosilicon compound: HMDSO: (CH ₃ ) ₆ Si ₂ O :) as a source gas and oxygen (O ₂ ) as a reaction gas is used as a film forming gas, Taking a case of producing a silicon-oxygen-based gas barrier layer as an example, a suitable ratio of the raw material gas to the reactive gas in the film forming gas will be described in more detail.

A film-forming gas containing hexamethyldisiloxane (HMDSO, (CH ₃ ) ₆ Si ₂ O) as a source gas and oxygen (O ₂ ) as a reaction gas is reacted by plasma CVD to form a silicon-oxygen-based material. When producing a gas barrier layer, the following reaction formula (3) in the film-forming gas:
(CH ₃ ) ₆ Si ₂ O + 12O ₂ → 6CO ₂ + 9H ₂ O + 2SiO ₂ (3)
The reaction represented by this occurs and silicon dioxide is formed. In this reaction, the amount of oxygen necessary to completely oxidize 1 mol of hexamethyldisiloxane is 12 mol. Therefore, a uniform silicon dioxide film can be formed when 12 moles or more of oxygen is contained in 1 mole of hexamethyldisiloxane and completely reacted in the film forming gas. In that case, there is a high possibility that a gas barrier layer satisfying all the above conditions (i) to (iii) cannot be formed. Therefore, when the gas barrier layer according to this embodiment is formed, the oxygen amount is set to a stoichiometric ratio of 12 with respect to 1 mol of hexamethyldisiloxane so that the reaction of the above formula (3) does not proceed completely. It is preferable to make it less than a mole. In the actual reaction in the plasma CVD chamber, the raw material hexamethyldisiloxane and the reaction gas oxygen are supplied from the gas supply unit to the film formation region to form a film, so the molar amount (flow rate) of oxygen in the reaction gas Even though the molar amount (flow rate) is 12 times the molar amount (flow rate) of the raw material hexamethyldisiloxane, in reality, the reaction does not proceed completely, and oxygen is compared to the stoichiometric ratio. It is thought that the reaction is often completed only when a large excess is supplied. For example, in order to obtain silicon oxide by complete oxidation by CVD, the molar amount (flow rate) of oxygen may be about 20 times or more the molar amount (flow rate) of hexamethyldisiloxane as a raw material. Therefore, the molar amount (flow rate) of oxygen with respect to the molar amount (flow rate) of the raw material hexamethyldisiloxane is preferably an amount of 12 times or less (more preferably 10 times or less) which is the stoichiometric ratio. . By containing hexamethyldisiloxane and oxygen in the film forming gas at such a ratio, carbon atoms and hydrogen atoms in hexamethyldisiloxane that have not been completely oxidized are taken into the gas barrier layer. As a result, a gas barrier layer that satisfies all the above conditions (i) to (iii) can be formed. Thereby, it becomes possible to exhibit the outstanding barrier property and bending resistance in the 2nd film obtained. If the molar amount (flow rate) of oxygen relative to the molar amount (flow rate) of hexamethyldisiloxane in the film forming gas is too small, unoxidized carbon atoms and hydrogen atoms are excessively taken into the gas barrier layer. In this case, since the transparency of the gas barrier layer is lowered, it becomes difficult to use the gas barrier layer as a flexible substrate for devices that require transparency, such as organic EL devices and organic thin-film solar cells. From such a viewpoint, the molar amount (flow rate) of oxygen with respect to the molar amount (flow rate) of hexamethyldisiloxane in the film forming gas is greater than 0.1 times the molar amount (flow rate) of hexamethyldisiloxane. It is preferable that the amount is more than 0.5 times.

The pressure in the vacuum chamber (degree of vacuum) can be adjusted as appropriate according to the type of source gas, but is preferably in the range of 0.1 Pa to 50 Pa.

In such a plasma CVD method, in order to discharge between the

film forming rolls

31 and 32, an electrode drum connected to the plasma generating power supply 51 (in this embodiment, the

film forming rolls

31 and 32 are installed). ) Is appropriately adjusted according to the type of source gas and the pressure in the vacuum chamber, but is preferably 0.1 to 10 kW. If the applied power is less than the lower limit, particles tend to be generated. If the applied power exceeds the upper limit, the amount of heat generated during film formation increases, and the temperature of the substrate surface during film formation increases. If the temperature rises too much, the substrate may be damaged by heat, and wrinkles may occur during film formation. In some cases, the film melts due to heat, the film formation roll is exposed, and a large current flows between the film formation rolls. There is a possibility that the film forming roll itself may be damaged due to the occurrence of the discharge.

The conveyance speed (line speed) of the substrate 6 can be appropriately adjusted according to the type of source gas, the pressure in the vacuum chamber, etc., but is preferably 0.1 to 100 m / min, 0.5 More preferably, it is ˜20 m / min. When the line speed is less than the lower limit, wrinkles due to heat tend to occur in the film, and when the line speed exceeds the upper limit, the thickness of the formed gas barrier layer tends to be thin.

(Second film)
As described above, when the light emitted from the organic EL element is emitted to the outside through the second film, the second film needs to be formed of a member that exhibits light transmittance. In that case, it is preferable that the 2nd film has a 2nd gas barrier layer similarly to the 1st film. The second gas barrier layer according to an embodiment contains silicon atoms, oxygen atoms, and carbon atoms, and the silicon distribution curve, oxygen distribution curve, and carbon distribution curve in the second gas barrier layer satisfy the above-described conditions (i ) To (iii) are satisfied. This second gas barrier layer can be formed by the same method as the gas barrier layer in the first film described above. The second gas barrier layer may have exactly the same configuration as the gas barrier layer of the first film, but as long as the oxygen distribution curve and the carbon distribution curve satisfy the conditions (i) to (iii), The film may have a different structure from the gas barrier layer.

(Light extraction structure)
Next, the light extraction structure will be described. The light extraction structure 14 used in the organic EL device according to this embodiment is provided on the outermost side of the organic EL device. However, this organic EL device may be further incorporated into another device or housing.

The structure of the light extraction structure is not particularly limited as long as it has an effect of increasing the light extraction efficiency, but preferably has the following characteristics. In other words, the intensity of light that enters the light extraction structure and exits from the surface from which the light is extracted (exit surface), and the virtual structure in which the surface from which the light is extracted (exit surface) is planar. When compared with the intensity of light emitted from the exit surface of the body, both the front intensity and the integrated intensity of the light extraction structure are 1.3 times or more compared to the front intensity and the integrated intensity of the virtual structure. As described above, it is preferable that the exit surface of the light extraction structure has an uneven structure. The magnifications of the front intensity and the integrated intensity are, for example, the evaluation light emitting device (organic EL device) provided with the extraction structure and the evaluation light emitting device except that the extraction structure is not provided. It can be estimated by comparing with a reference light emitting device (organic EL device) having the same configuration as the above and having a flat emission surface. In this case, a member (for example, a glass substrate as a support substrate) constituting the emission surface of the reference light emitting device corresponds to a light extraction structure as a virtual structure.

FIG. 5 is a diagram schematically showing an example of the light extraction structure 14. FIG. 5 (1) is a side view, and FIG. 5 (2) is a plan view seen from the exit surface side.

The light extraction structure 14 has a main surface opposite to the surface on which the light L is incident as the emission surface S. The exit surface S of the light extraction structure 14 forms an uneven structure. This concavo-convex structure is incident on the light extraction structure 14 and when the intensity of light emitted from the emission surface S is compared with the intensity of light emitted from the emission surface of the virtual structure having a planar emission surface. Both the front intensity and the integrated intensity of the light emitted from the light extraction structure 14 have a shape that is 1.3 times or more that of the light emitted from the virtual structure. The light exit structure S of FIG. 5 has a concavo-convex structure formed by a plurality of granular structures 14 a that are dispersed in the light exit surface S.

FIG. 6 is a diagram schematically showing the virtual structure 110 to be compared with the light extraction structure 14. FIG. 6A is a side view of the virtual structure 110, and FIG. 6B is a plan view of the virtual structure 110. As shown in FIG. 6, both of a pair of opposing main surfaces of the virtual structure 110 are planar. That is, the virtual structure 110 does not have an uneven structure. The virtual structure 110 has the same configuration as the light extraction structure 14 except that the surface shape is different.

When the same light (light emitted from the same light source) is incident on the light extraction structure 14 having an uneven structure and the virtual structure 110 not having an uneven structure under the same conditions, the light extraction structure 14 The front intensity of the light emitted from the virtual structure 110 is 1.3 times or more, more preferably 1.4 times or more than the front intensity of the light emitted from the virtual structure 110. Further, when the same light (light emitted from the same light source) is incident on the light extraction structure 14 having the concavo-convex structure and the virtual structure 110 having no concavo-convex structure under the same conditions, the light extraction structure The integrated intensity of light emitted from the body 14 is 1.3 times or more, more preferably 1.31 times or more than the integrated intensity of light emitted from the virtual structure 110. The magnification of the front strength and the integral strength may be 1.3 times or more, and the upper limit is not particularly limited, but it may not be appropriate if only the front strength becomes too strong, so the magnification of the front strength is, for example, 5 times or less. The integral intensity magnification is, for example, 5 times or less.

The front intensity of the emitted light is the intensity of light emitted in the thickness direction of the light extraction structure 14. Assuming a plane in which the uneven structure of the light extraction structure 14 is macroscopically averaged, the normal direction of the plane coincides with the thickness direction of the light extraction structure 14. Therefore, when viewed macroscopically, the front intensity of the emitted light represents the light intensity in the normal direction of the surface (exit surface S) of the light extraction structure 14.

The integrated intensity of the emitted light is a value obtained by integrating the intensity of the light emitted in all directions as well as the normal direction with respect to the light emitted from the light source through the light extraction structure.

An organic EL element is used as a light source for various devices, but required characteristics vary depending on a device on which the organic EL element is mounted. For example, while there are devices that require high brightness in the normal direction, there are also devices that are required to emit light uniformly in all directions. In other words, there is a device that is not suitable for a device that projects only in the normal direction and has high luminance. For example, in the case of a light source that requires uniform light emission, such as general illumination, a light extraction structure with high diffusibility is required. Therefore, conventionally, even at the expense of light intensity in directions other than the normal direction (so-called oblique direction), research and development aimed at improving the frontal strength, and even in the direction of the frontal strength, uniform in all directions Research and development aimed at light emission have been carried out. Under such circumstances, the present inventors have taken out the light so that both the front intensity and the integrated intensity of the light emitting device are 1.3 times or more as compared with the light emitting device having a flat emission surface. It has been found that a particularly useful light-emitting device can be obtained by applying the structure 14 to an organic EL element. For example, when an organic EL element is used as a light source of a lighting device, a lighting device having a high front intensity of emitted light and capable of illuminating a room or the like is preferable, but compared with a light emitting device having a flat emission surface. Then, such a lighting device can be realized by applying the light extraction structure 14 in which both the front intensity and the integrated intensity are 1.3 times or more to the organic EL element. This utilizes the property peculiar to the organic EL element that the element itself can be a planar light source (two-dimensional light source).

For example, since inorganic LEDs and fluorescent lamps are point-like (zero-dimensional) or linear (one-dimensional) light sources, diffusivity is more important than frontal intensity when using them as lighting devices. For this reason, the application of a light extraction structure that increases the integrated intensity has been studied. However, since the organic EL element can be a planar light source (two-dimensional light source), by applying the light extraction structure 14 that increases both the front intensity and the integrated intensity, the organic EL element can be used as an illumination device. Performance can be improved.

Regarding the light extraction structure 14, it is preferable that the ratio of I (θ °) described below satisfies the following formula (4), the haze value is 60% or more, and the total light transmittance is 60% or more.
I (35) / I (70)> 5 Formula (4)
The ratio of I (θ °) is sometimes referred to as a diffusion parameter. I (θ °) is the angle θ ° to the normal direction of the main surface of the light extraction structure when light from a planar light source arranged parallel to the light extraction structure is incident on the light extraction structure Means the intensity of light emitted from the light extraction structure in the direction of

By using the light extraction structure 14 having a haze value of 60% or more and a total light transmittance of 60% or more, a light emitting device exhibiting particularly high extraction efficiency can be realized.

The haze value is represented by the following formula. The haze value can be measured by the method described in JIS K 7136 “Plastics—How to determine haze of transparent material”.
Haze value (cloudiness value) = (diffuse transmittance (%) / total light transmittance (%)) × 100 (%).

The total light transmittance can be measured by the method described in JIS K 7361-1 “Testing method of total light transmittance of plastic-transparent material”.

FIG. 7 is a diagram for explaining I (θ °). The intensity of light emitted in the normal direction of the emission surface of the light extraction device is defined as I (0). The planar light source 210 is arranged in parallel to the light extraction structure 14 so that the light emitting surface thereof is parallel to the main surface of the light extraction structure 14. As described above, since the organic EL element itself is a planar light source, the planar light source 210 can be regarded as a simulated organic EL element. A specific method for measuring I (θ °) will be described in the Examples section.

I (35) represents the intensity of light in a direction inclined by 35 ° from the normal direction, and I (70) represents the intensity of light in a direction inclined by 70 ° from the normal direction. A high I (35) / I (70) corresponds to the emission of stronger light in the front direction. When I (35) / I (70) exceeds 5, this light extraction structure 14 can be used particularly suitably for an illumination device, for example. If I (35) / I (70) is too high, only the light intensity in the front direction becomes too high. Therefore, it is preferably 30 or less in order to illuminate a wide range.

It is preferable that the light extraction structure 14 further satisfies the following formula (5).
I (0) / I (35)> 1.5 Formula (5)
A high I (0) / I (35) corresponds to the emission of stronger light in the front direction. When this ratio exceeds 1.5, the light extraction structure 14 can be used particularly suitably for an illumination device, for example. If I (0) / I (35) is too high, only the light intensity in the front direction becomes too high. Therefore, it is preferably 10 or less in order to illuminate a wide range.

The concavo-convex structure of the light extraction structure 14 is preferably formed by a plurality of granular structures dispersed and arranged on the surface of the light extraction structure 14. The granular structure may be attached to a flat surface or may be formed integrally with the main body of the structure on the exit surface. The granular structures may be arranged periodically or aperiodically. In the case where the granular structures are arranged aperiodically, light interference caused by the granular structures can be suppressed, so that occurrence of moire or the like can be prevented. An example of a light extraction structure having a concavo-convex structure formed by a plurality of granular structures arranged dispersed on the surface is shown in FIGS. 17, 19, and 20.

Hereinafter, a preferred embodiment of the concavo-convex structure, particularly a preferred embodiment for making the front intensity and the integrated intensity of the light extraction structure at least 1.3 times that of the virtual structure will be described in detail.

The concavo-convex structure includes, for example, a plurality of concave structures having a flat bottom surface, and a convex structure that is arranged around each concave structure and protrudes away from the bottom surface of the concave structure. Each concave structure or each convex structure constituting the concavo-convex structure has such a width and height that the light extraction efficiency is improved. The width of each concave structure or each convex structure means a size in a direction parallel to the main surface of the light extraction structure 14. The width of each concave structure is, for example, the maximum width of a flat bottom surface in a cross section perpendicular to the main surface of the light extraction structure. The width of each convex structure is, for example, the maximum width of the skirt of the convex structure in a cross section perpendicular to the main surface of the light extraction structure. The height of each convex structure means the height in the normal direction of the main surface of the light extraction structure 14, and is, for example, the height with respect to the bottom surface of the concave structure. If the width of each concave structure and each convex structure is too large, the luminance on the surface of the light extraction structure 14 becomes nonuniform, and if it is too small, the production cost of the light extraction structure 14 increases. Therefore, the width of each concave structure and each convex structure is preferably 0.5 μm to 100 μm, and more preferably 1 μm to 50 μm. The height of each convex structure is usually determined according to the width of each concave structure or each convex structure and the period in which each concave structure or each convex structure is provided (for example, the distance between the vertices of adjacent convex structures). It is preferable that the width is equal to or less than the width of each concave structure or each convex structure, or equal to or less than the period in which each concave structure or each convex structure is provided. The height of each convex structure is preferably 0.25 μm to 70 μm, more preferably 0.5 μm to 50 μm.

The shape of each concave structure or each convex structure is not particularly limited, but preferably has a curved surface. The convex structure preferably has, for example, a hemispherical shape. It is preferable that the concave structures or the convex structures are arranged aperiodically because moire can be prevented. The total area occupied by the region where the concavo-convex structure is formed on the surface of the light extraction structure 14 when viewed from one of the normal directions of the main surface of the light extraction structure 14 is the light extraction structure 14. It is preferable that it is 60% or more of the area of the main surface.

The material constituting the light extraction structure 14 may be a transparent material, for example, an inorganic substance such as glass, or an organic substance (low molecular compound or high molecular compound). The polymer compound contained in the light extraction structure 14 is, for example, at least one selected from the group consisting of polyarylate, polycarbonate, polycycloolefin, polyethylene naphthalate, polyethylene sulfonic acid, and polyethylene terephthalate. The thickness of the light extraction structure 14 is not particularly limited, but if it is too thin, it becomes difficult to handle, and if it is too thick, the total light transmittance decreases. Therefore, the thickness of the light extraction structure 14 is preferably 50 μm to 2 mm, more preferably 80 μm to 1.5 mm.

The light extraction structure made of an inorganic material such as glass can be obtained, for example, by etching a flat base made of an inorganic material. For example, a light extraction structure can be obtained by selectively etching a portion where a concavo-convex shape (concavo-convex structure) is formed on the surface of a flat base. Specifically, a concavo-convex structure can be formed by patterning a protective film on the surface of a base made of an inorganic material and performing liquid phase etching or gas phase etching. The protective film can be patterned using, for example, a photoresist.

The light extraction structure made of an organic material can be formed, for example, by the following methods (1) to (5).
(1) A method of transferring a concavo-convex shape of a metal plate to a film by pressing a metal plate having a concavo-convex surface against a flat surface of a heated film.
(2) A method of rolling a film having a flat surface using a roll having an uneven surface.
(3) A method of forming a film of an organic material by dropping a solution or dispersion containing the organic material onto a base having an uneven surface.
(4) A method of selectively photopolymerizing a part of a film containing a polymerizable monomer and removing an unpolymerized part.
(5) A method in which a polymer solution is cast on a base under high humidity conditions, and a water droplet structure is transferred to the surface.

For example, the light extraction structure 14 may be directly formed on the first film shown in FIG. 1, or by processing the surface of the first film to form a concavo-convex structure, It may be formed integrally with the first film on the surface portion.

When an air layer is formed between the light extraction structure 14 and the first film or the second film when the light extraction structure 14 is bonded to the first film or the second film, Light reflection may occur at the interface of the air layer, which may reduce the light extraction efficiency. Therefore, it is preferable that the light extraction structure 14 and the first film or the second film are bonded through an adhesive layer so that an air layer is not formed therebetween.

The difference (absolute value) between the maximum value and the minimum value among the refractive index nf of the light extraction structure 14, the refractive index na of the adhesive layer, and the refractive index ns of the first film or the second film is 0. Preferably it is less than 2. By satisfying such a refractive index relationship, reflection that occurs between the light extraction structure 14 and the first film or the second film can be suppressed, and the light extraction efficiency can be further improved. it can.

The total thickness of the light extraction structure 14 and the first film and the second film is not particularly limited, but the light extraction structure 14 including the adhesive layer interposed therebetween, the first film, and the first film The total thickness with the film 2 is preferably 50 μm to 2 mm, more preferably 80 μm to 1.5 mm.

(Organic EL device)
Next, the configuration of the organic EL element will be described. The organic EL element is formed on the first film or the second film before the step of bonding the first film and the second film.

The organic EL element is composed of a pair of electrodes composed of an anode and a cathode, and a light emitting layer provided between the electrodes. In addition to the light-emitting layer, a predetermined layer may be provided between the pair of electrodes as necessary. The light emitting layer is not limited to one layer, and a plurality of layers may be provided.

Examples of the layer provided between the cathode and the light emitting layer include an electron injection layer, an electron transport layer, and a hole blocking layer. In the case where both the electron injection layer and the electron transport layer are provided between the cathode and the light emitting layer, the layer in contact with the cathode is referred to as an electron injection layer, and the layer excluding this electron injection layer is referred to as an electron transport layer.

The electron injection layer has a function of improving the electron injection efficiency from the cathode. The electron transport layer has a function of improving electron injection from the layer in contact with the surface on the cathode side. The hole blocking layer has a function of blocking hole transport. When the electron injection layer and / or the electron transport layer has a function of blocking hole transport, these layers may also serve as the hole blocking layer.

The fact that the hole blocking layer has a function of blocking hole transport can be confirmed, for example, by fabricating a device that allows only the hole current to flow and reducing the current value.

Examples of the layer provided between the anode and the light emitting layer include a hole injection layer, a hole transport layer, and an electron block layer. When both the hole injection layer and the hole transport layer are provided between the anode and the light-emitting layer, the layer in contact with the anode is called a hole injection layer, and the layers other than the hole injection layer are positive. It is called a hole transport layer.

The hole injection layer has a function of improving the hole injection efficiency from the anode. The hole transport layer has a function of improving hole injection from a layer in contact with the surface on the anode side. The electron blocking layer has a function of blocking electron transport. When the hole injection layer and / or the hole transport layer have a function of blocking electron transport, these layers may also serve as the electron block layer.

The fact that the electron blocking layer has a function of blocking electron transport can be confirmed, for example, by producing an element that allows only an electron current to flow and reducing the current value.

The electron injection layer and the hole injection layer may be collectively referred to as a charge injection layer, and the electron transport layer and the hole transport layer may be collectively referred to as a charge transport layer.

An example of the layer structure that the organic EL element of the present embodiment can have is shown below.
a) anode / light emitting layer / cathode b) anode / hole injection layer / light emitting layer / cathode c) anode / hole injection layer / light emitting layer / electron injection layer / cathode d) anode / hole injection layer / light emitting layer / Electron transport layer / cathode e) anode / hole injection layer / light emitting layer / electron transport layer / electron injection layer / cathode f) anode / hole transport layer / light emitting layer / cathode g) anode / hole transport layer / light emitting layer / Electron injection layer / cathode h) anode / hole transport layer / light emitting layer / electron transport layer / cathode i) anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode j) anode / hole Injection layer / hole transport layer / light emitting layer / cathode k) anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode l) anode / hole injection layer / hole transport layer / light emitting layer / Electron transport layer / cathode m) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode n) anode / light emitting layer / electron injection layer / cathode o) anode / Photo layer / electron transport layer / cathode p) anode / light emitting layer / electron transport layer / electron injection layer / cathode (here, the symbol “/” indicates that the two layers described with the symbol “/” in between are (Indicates that they are stacked adjacently. The same shall apply hereinafter.)

The organic EL element of the present embodiment may have two or more light emitting layers. In any one of the layer configurations of a) to p) above, when the laminate sandwiched between the anode and the cathode is referred to as “structural unit A”, the configuration of an organic EL element having two light emitting layers is obtained. And the layer structure shown in the following q). The two (structural unit A) layer structures may be the same or different.
q) Anode / (structural unit A) / charge generation layer / (structural unit A) / cathode

When “(structural unit A) / charge generation layer” is “structural unit B”, examples of the configuration of the organic EL device having three or more light emitting layers include the layer configuration shown in the following r).
r) Anode / (Structural unit B) x / (Structural unit A) / Cathode The symbol “x” represents an integer of 2 or more, and (Structural unit B) x is a stacked layer of the structural units B stacked in x stages. Represents the body. A plurality of (structural unit B) layer structures may be the same or different.

The charge generation layer is a layer that generates holes and electrons by applying an electric field. Examples of the charge generation layer include a thin film containing vanadium oxide, indium tin oxide (abbreviated as ITO), molybdenum oxide, and the like.

The order of the layers to be laminated, the number of layers, and the thickness of each layer can be appropriately set in consideration of the light emission efficiency and the element lifetime.

Next, the material and forming method of each layer constituting the organic EL element will be described more specifically.

<Anode>
In the case of an organic EL element having a configuration in which light emitted from the light emitting layer is emitted outside through the anode, an electrode exhibiting light transmittance is used as the anode. As an electrode exhibiting light transmittance, a thin film of metal oxide, metal sulfide, metal, or the like can be used, and an electrode having high electrical conductivity and light transmittance is preferable. Specifically, a thin film containing indium oxide, zinc oxide, tin oxide, ITO, indium zinc oxide (abbreviated as IZO), gold, platinum, silver, copper, or the like is used. Among these, a thin film made of ITO, IZO, or tin oxide is preferable. Examples of the method for producing the anode include a vacuum deposition method, a sputtering method, an ion plating method, and a plating method. As the anode, an organic transparent conductive film such as polyaniline or a derivative thereof and polythiophene or a derivative thereof may be used.

The thickness of the anode is appropriately set in consideration of required characteristics and process simplicity, and is, for example, 10 nm to 10 μm, preferably 20 nm to 1 μm, and more preferably 50 nm to 500 nm.

<Hole injection layer>
The hole injection material constituting the hole injection layer includes oxides such as vanadium oxide, molybdenum oxide, ruthenium oxide, and aluminum oxide, phenylamine compounds, starburst amine compounds, phthalocyanines, amorphous carbon, polyaniline And polythiophene derivatives.

Examples of the method for forming the hole injection layer include film formation from a solution containing a hole injection material. For example, a hole injection layer can be formed by applying a solution containing a hole injection material by a predetermined application method to form a film, and solidifying the formed solution.

The solvent used for film formation from a solution is not particularly limited as long as it dissolves the hole injection material. Chlorine solvents such as chloroform, methylene chloride and dichloroethane, ether solvents such as tetrahydrofuran, toluene and xylene And aromatic hydrocarbon solvents such as acetone, ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate, butyl acetate and ethyl cellosolve acetate, and water.

As coating methods, spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method, spray coating method, screen printing method, flexographic printing method, offset Examples thereof include a printing method and an ink jet printing method.

The thickness of the hole injection layer is appropriately set in consideration of required characteristics and process simplicity, and is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm.

<Hole transport layer>
As the hole transport material constituting the hole transport layer, polyvinylcarbazole or a derivative thereof, polysilane or a derivative thereof, a polysiloxane derivative having an aromatic amine in a side chain or a main chain, a pyrazoline derivative, an arylamine derivative, a stilbene derivative, Triphenyldiamine derivative, polyaniline or derivative thereof, polythiophene or derivative thereof, polyarylamine or derivative thereof, polypyrrole or derivative thereof, poly (p-phenylenevinylene) or derivative thereof, and poly (2,5-thienylenevinylene) or Examples thereof include derivatives thereof.

Among these, hole transport materials include polyvinyl carbazole or derivatives thereof, polysilane or derivatives thereof, polysiloxane derivatives having aromatic amine compound groups in the side chain or main chain, polyaniline or derivatives thereof, polythiophene or derivatives thereof, poly Polymeric hole transport materials such as arylamines or derivatives thereof, poly (p-phenylene vinylene) or derivatives thereof, and poly (2,5-thienylene vinylene) or derivatives thereof are preferred. More preferable hole transport materials are polyvinyl carbazole or a derivative thereof, polysilane or a derivative thereof, and a polysiloxane derivative having an aromatic amine in a side chain or a main chain. The low molecular hole transport material is preferably used by being dispersed in a polymer binder.

The method for forming the hole transport layer is not particularly limited, but in the case of a low molecular hole transport material, film formation from a mixed solution containing a polymer binder and a hole transport material can be exemplified. Examples of molecular hole transport materials include film formation from a solution containing a hole transport material.

The solvent used for film formation from a solution is not particularly limited as long as it can dissolve a hole transport material. Chlorine solvents such as chloroform, methylene chloride and dichloroethane, ether solvents such as tetrahydrofuran, toluene and xylene And aromatic hydrocarbon solvents such as ketone solvents such as acetone and methyl ethyl ketone, and ester solvents such as ethyl acetate, butyl acetate and ethyl cellosolve acetate.

As a film formation method from a solution, the same coating method as the above-described film formation method of the hole injection layer can be exemplified.

It is preferable that the polymer binder combined with the hole transport material does not extremely impede charge transport, and that absorption with respect to visible light is weak. The polymer binder is selected from, for example, polycarbonate, polyacrylate, polymethyl acrylate, polymethyl methacrylate, polystyrene, polyvinyl chloride, and polysiloxane.

The thickness of the hole transport layer varies depending on the material used, and is appropriately set so that the drive voltage and the light emission efficiency are appropriate. The hole transport film must have at least a thickness that does not cause pinholes. If the hole transport film is too thick, the drive voltage of the device increases. Therefore, the thickness of the hole transport layer is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, more preferably 5 nm to 200 nm.

<Light emitting layer>
The light emitting layer is usually formed of an organic substance (light emitting material) that mainly emits fluorescence and / or phosphorescence, or the organic substance and a dopant that assists the organic substance. The dopant is added, for example, to improve the luminous efficiency or to change the emission wavelength. The organic substance contained in the light emitting layer may be a low molecular compound or a high molecular compound. In general, since a polymer compound having higher solubility in a solvent than a low molecule is preferably used in the coating method, the light emitting layer preferably contains a polymer compound. The light emitting layer preferably contains a high molecular compound having a polystyrene-reduced number average molecular weight of 10 ³ to 10 ⁸ . Examples of the light emitting material constituting the light emitting layer include the following dye materials, metal complex materials, polymer materials, and dopant materials.

(Dye material)
Examples of dye-based materials include cyclopentamine derivatives, tetraphenylbutadiene derivative compounds, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, pyrrole derivatives, thiophene ring compounds. Pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, oxadiazole dimers, pyrazoline dimers, quinacridone derivatives, and coumarin derivatives.

(Metal complex materials)
Examples of the metal complex material include rare earth metals such as Tb, Eu, and Dy, and a central metal selected from Al, Zn, Be, Ir, Pt, and the like, oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, and the like. A metal complex having a ligand selected from a quinoline structure and the like can be given. Metal complex materials include, for example, metal complexes that emit light from triplet excited states such as iridium complexes and platinum complexes, aluminum quinolinol complexes, benzoquinolinol beryllium complexes, benzoxazolyl zinc complexes, benzothiazole zinc complexes, azomethyl zinc Selected from complexes, porphyrin zinc complexes, and phenanthroline europium complexes.

(Polymer material)
As polymer materials, polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, the above dye materials or metal complex light emitting materials are polymerized. Materials etc. can be mentioned.

Among the above light emitting materials, examples of materials that emit blue light include distyrylarylene derivatives, oxadiazole derivatives, and polymers thereof, polyvinylcarbazole derivatives, polyparaphenylene derivatives, and polyfluorene derivatives. . Of these, polymer materials such as polyvinyl carbazole derivatives, polyparaphenylene derivatives, and polyfluorene derivatives are preferred.

Examples of materials that emit green light include quinacridone derivatives, coumarin derivatives, and polymers thereof, polyparaphenylene vinylene derivatives, and polyfluorene derivatives. Of these, polymer materials such as polyparaphenylene vinylene derivatives and polyfluorene derivatives are preferred.

Examples of materials that emit red light include coumarin derivatives, thiophene ring compounds, and polymers thereof, polyparaphenylene vinylene derivatives, polythiophene derivatives, and polyfluorene derivatives. Of these, polymer materials such as polyparaphenylene vinylene derivatives, polythiophene derivatives, and polyfluorene derivatives are preferred.

In addition, as a material that emits white light, a material obtained by mixing the above-described materials that emit light in blue, green, and red, or a component that becomes a material that emits light in each color is used as a monomer, and a polymer obtained by polymerizing this is used as the material. May be. Alternatively, an element that emits white light as a whole may be realized by stacking light emitting layers formed using materials that emit light of each color.

(Dopant material)
Examples of the dopant material include perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squalium derivatives, porphyrin derivatives, styryl dyes, tetracene derivatives, pyrazolone derivatives, decacyclene, and phenoxazone. The thickness of the light emitting layer is usually about 2 nm to 200 nm.

<Method for forming light emitting layer>
As a method for forming the light emitting layer, a method of applying a solution containing a light emitting material, a vacuum deposition method, a transfer method, or the like can be used. Examples of the solvent used for film formation from a solution include the same solvents as those described above used for forming a hole injection layer from a solution.

As a method for applying a solution containing a light emitting material, a spin coating method, a casting method, a micro gravure coating method, a gravure coating method, a bar coating method, a roll coating method, a wire bar coating method, a dip coating method, a slit coating method, a capillary Examples include coating methods such as coating methods, spray coating methods, and nozzle coating methods, and printing methods such as gravure printing methods, screen printing methods, flexographic printing methods, offset printing methods, reversal printing methods, and inkjet printing methods. . A printing method such as a gravure printing method, a screen printing method, a flexographic printing method, an offset printing method, a reverse printing method, and an ink jet printing method is preferable in that pattern formation and multicolor coating are easy. In the case of a low molecular compound exhibiting sublimability, a vacuum deposition method can be used. A method of forming a light emitting layer only at a desired portion by laser transfer or thermal transfer can also be used.

<Electron transport layer>
As an electron transport material constituting the electron transport layer, a commonly used material can be used, such as an oxadiazole derivative, anthraquinodimethane or a derivative thereof, benzoquinone or a derivative thereof, naphthoquinone or a derivative thereof, anthraquinone or a derivative thereof, Tetracyanoanthraquinodimethane or derivatives thereof, fluorenone derivatives, diphenyldicyanoethylene or derivatives thereof, diphenoquinone derivatives, or metal complexes of 8-hydroxyquinoline or derivatives thereof, polyquinoline or derivatives thereof, polyquinoxaline or derivatives thereof, and polyfluorene or Examples thereof include derivatives thereof.

Among these, electron transport materials include oxadiazole derivatives, benzoquinone or derivatives thereof, anthraquinones or derivatives thereof, or metal complexes of 8-hydroxyquinoline or derivatives thereof, polyquinoline or derivatives thereof, polyquinoxaline or derivatives thereof, and poly Fluorene or its derivatives are preferred, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole, benzoquinone, anthraquinone, tris (8-quinolinol) aluminum, and polyquinoline Is more preferable.

The method for forming the electron transport layer is not particularly limited. In the case of a low-molecular electron transport material, a vacuum deposition method from powder, or film formation from a solution or a molten state can be exemplified, and in the case of a polymer electron transport material, film formation from a solution or a melt state can be exemplified. be able to. In the case of film formation from a solution or a molten state, a polymer binder may be used in combination. Examples of the method for forming an electron transport layer from a solution include the same film formation method as the method for forming a hole injection layer from a solution described above.

The thickness of the electron transport layer varies depending on the material used, and is appropriately set so that the drive voltage and the light emission efficiency are appropriate. The electron transport layer needs to have at least a thickness that does not generate pinholes, and if it is too thick, the drive voltage of the device increases. Accordingly, the thickness of the electron transport layer is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm.

<Electron injection layer>
As a material constituting the electron injection layer, an optimum material is appropriately selected according to the type of the light emitting layer. As a material constituting the electron injection layer, an alloy containing one or more kinds of metals selected from alkali metals, alkaline earth metals, alkali metals and alkaline earth metals, oxides of alkali metals or alkaline earth metals, halides, Mention may be made of carbonates and mixtures of these substances. Examples of alkali metals, alkali metal oxides, halides, and carbonates include lithium, sodium, potassium, rubidium, cesium, lithium oxide, lithium fluoride, sodium oxide, sodium fluoride, potassium oxide, potassium fluoride , Rubidium oxide, rubidium fluoride, cesium oxide, cesium fluoride and lithium carbonate. Examples of alkaline earth metal, alkaline earth metal oxides, halides and carbonates include magnesium, calcium, barium, strontium, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, barium oxide, fluoride Examples thereof include barium, strontium oxide, strontium fluoride and magnesium carbonate. The electron injection layer may be composed of a laminate in which two or more layers are laminated. An example of a laminate of electron injection layers is LiF / Ca. The electron injection layer is formed by vapor deposition, sputtering, printing, or the like. The thickness of the electron injection layer is preferably about 1 nm to 1 μm.

<Cathode>
A material for the cathode is preferably a material having a low work function, easy electron injection into the light emitting layer, and high electrical conductivity. In the case of an organic EL element configured to extract light from the anode side, a material having a high visible light reflectivity is preferable as the cathode material in order to reflect light emitted from the light emitting layer to the anode side at the cathode. As the material of the cathode, for example, alkali metal, alkaline earth metal, transition metal, and Group 13 metal of the periodic table can be used. Examples of cathode materials include lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, ytterbium, and the like. And an alloy containing two or more metals selected from these metals, one or more selected from the above metals, and one selected from gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten and tin Alloys with seeds or more, or graphite or graphite intercalation compounds are used. Examples of alloys include magnesium-silver alloys, magnesium-indium alloys, magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum alloys, lithium-magnesium alloys, lithium-indium alloys, and calcium-aluminum alloys. Can do. As the cathode, a transparent conductive electrode made of a conductive metal oxide, a conductive organic material, or the like can be used. Specifically, examples of the conductive metal oxide include indium oxide, zinc oxide, tin oxide, ITO, and IZO, and examples of the conductive organic substance include polyaniline or a derivative thereof and polythiophene or a derivative thereof. . The cathode may be composed of a laminate in which two or more layers are laminated. In some cases, the electron injection layer is used as a cathode.

The thickness of the cathode is appropriately designed in consideration of required characteristics and process simplicity, and is, for example, 10 nm to 10 μm, preferably 20 nm to 1 μm, more preferably 50 nm to 500 nm.

Examples of the method for producing the cathode include a vacuum deposition method, a sputtering method, and a lamination method in which a metal thin film is thermocompression bonded.

The above organic EL device can be used as a lighting device, a surface light source device, or a display device by adding predetermined components.

(Reference Example A1)
A first film was produced using the production apparatus shown in FIG. That is, a biaxially stretched polyethylene naphthalate film (PEN film, thickness: 100 μm, width: 350 mm, manufactured by Teijin DuPont Films, trade name “Teonex Q65FA”) is used as a base material (base material 6), and this is sent out. Mounted on a roll 701. And while applying a magnetic field between the film-forming roll 31 and the film-forming roll 32 and supplying electric power to each of the film-forming roll 31 and the film-forming roll 32, Was discharged to generate plasma. A film-forming gas (mixed gas of hexamethyldisiloxane (HMDSO) as a source gas and oxygen gas (which also functions as a discharge gas) as a source gas) is supplied to the formed discharge region under the following conditions A thin film was formed by a plasma CVD method to obtain a first film having a gas barrier layer.

<Film formation conditions>
Supply amount of source gas: 50 (Standard Cubic Centimeter per Minute converted to zero, 1 atm. The same shall apply hereinafter.)
Supply amount of oxygen gas: 500 sccm
Degree of vacuum in the vacuum chamber: 3Pa
Applied power from the power source for plasma generation: 0.8 kW
Frequency of power source for plasma generation: 70 kHz
Film conveyance speed: 0.5 m / min.

The thickness of the gas barrier layer in the obtained first film was 0.3 μm. Further, the water vapor permeability of the obtained first film was 3.1 × 10 ⁻⁴ g / (m under the conditions of a temperature of 40 ° C., a humidity of 0% RH on the low humidity side, and a humidity of 90% RH on the high humidity side. ² · day), a value below the detection limit under the conditions of a temperature of 40 ° C., a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Further, the water vapor permeability of the first film under the conditions of a temperature of 40 ° C. after bending the first film under the condition of a curvature radius of 8 mm, a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Is a value below the detection limit, and it was confirmed that even when the first film was bent, the decrease in gas barrier properties was sufficiently suppressed.

About the obtained 1st film, XPS depth profile measurement was performed on the following conditions, and the silicon distribution curve, the oxygen distribution curve, the carbon distribution curve, and the oxygen carbon distribution curve were obtained.
Etching ion species: Argon (Ar ⁺ )
Etching rate (SiO ₂ thermal oxide equivalent value): 0.05 nm / sec
Etching interval (SiO ₂ equivalent value): 10 nm
X-ray photoelectron spectrometer: Model “VG Theta Probe”, manufactured by Thermo Fisher Scientific
Irradiation X-ray: Single crystal spectroscopy AlKα
X-ray spot and size: 800 × 400 μm oval.

The obtained silicon distribution curve, oxygen distribution curve and carbon distribution curve are shown in FIG. Regarding the obtained silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen-carbon distribution curve, the atomic ratio (atomic concentration) and the distance from the surface of the gas barrier layer (atomic concentration) and the relationship between the etching time and the surface ( nm) is shown in the graph of FIG. “Distance (nm)” indicated on the horizontal axis of the graph of FIG. 9 is a value obtained by calculation from the etching time and the etching rate.

As is clear from the results shown in FIGS. 8 and 9, the obtained carbon distribution curve has a plurality of distinct extreme values, and the difference between the maximum value and the minimum value of the atomic ratio of carbon is 5 at. %, And in the region of 90% or more in the thickness direction of the gas barrier layer, the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon satisfy the conditions represented by the above formula (1). It was confirmed.

(Reference Example A2)
The first film having a gas barrier layer having a thickness of 0.3 μm obtained in Reference Example A1 was mounted on the delivery roll 701 as the base material 6, and a gas barrier layer was newly formed on the surface of the gas barrier layer. Otherwise in the same manner as in Reference Example A1, a first film (A) was obtained. The thickness of the gas barrier layer on the base material (PEN film) in the obtained first film (A) was 0.6 μm.

The obtained first film (A) was mounted on a delivery roll 701 as a base material 6, and a gas barrier layer was newly formed on the surface of the gas barrier layer. Otherwise in the same manner as in Reference Example A1, a first film (B) was obtained.

The thickness of the gas barrier layer in the obtained first film (B) was 0.9 μm. The water vapor permeability of the obtained first film (B) was 6.9 × 10 ⁻⁴ g / (under conditions of a temperature of 40 ° C., a humidity of 0% RH on the low humidity side, and a humidity of 90% RH on the high humidity side. m ² · day), which was below the detection limit under the conditions of a temperature of 40 ° C., a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Further, the first film (B) after bending the first film (B) under the condition of a curvature radius of 8 mm, under the conditions of a temperature of 40 ° C., a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side ( The water vapor permeability of B) was a value below the detection limit, and it was confirmed that the gas barrier property was sufficiently suppressed even when the first film (B) was bent.

For the obtained first film (B), a silicon distribution curve, an oxygen distribution curve, a carbon distribution curve, and an oxygen carbon distribution curve were prepared by the same method as in Reference Example A1. The obtained result is shown in FIG. Regarding the silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen carbon distribution curve, the relationship between the atomic ratio (atomic concentration) and the etching time, as well as the atomic ratio (atomic concentration) and the distance (nm) from the surface of the gas barrier layer. The relationship is shown in the graph of FIG. The “distance (nm)” described on the horizontal axis of the graph of FIG. 11 is a value obtained by calculation from the etching time and the etching rate.

As is apparent from the results shown in FIGS. 10 and 11, the obtained carbon distribution curve has a plurality of distinct extreme values, and the difference between the maximum value and the minimum value of the atomic ratio of carbon is 5 at. %, And in the region of 90% or more in the thickness direction of the gas barrier layer, the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon satisfy the conditions represented by the above formula (1). It was confirmed.

(Reference Example A3)
A first film was obtained in the same manner as in Reference Example A1, except that the supply amount of the source gas was changed to 100 sccm.

The thickness of the gas barrier layer in the obtained first film was 0.6 μm. The water vapor permeability of the obtained first film was 3.2 × 10 ⁻⁴ g / (m ² · m under the conditions of a temperature of 40 ° C., a humidity of 0% RH on the low humidity side, and a humidity of 90% RH on the high humidity side. day), a value below the detection limit under the conditions of a temperature of 40 ° C., a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Further, the water vapor permeability of the first film under the conditions of a temperature of 40 ° C. after bending the first film under the condition of a curvature radius of 8 mm, a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Is a value below the detection limit, and it was confirmed that even when the first film was bent, the decrease in gas barrier properties was sufficiently suppressed.

For the obtained first film, a silicon distribution curve, an oxygen distribution curve, a carbon distribution curve, and an oxygen carbon distribution curve were prepared by the same method as in Reference Example A1. The obtained silicon distribution curve, oxygen distribution curve and carbon distribution curve are shown in FIG. Regarding the obtained silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen-carbon distribution curve, the atomic ratio (atomic concentration) and the distance from the surface of the gas barrier layer (nm) as well as the relationship between the atomic ratio (atomic concentration) and etching time. The graph of FIG. “Distance (nm)” described on the horizontal axis of the graph of FIG. 13 is a value obtained by calculation from the etching time and the etching rate.

As is apparent from the results shown in FIGS. 12 and 13, the obtained carbon distribution curve has a plurality of distinct extreme values, and the difference between the maximum value and the minimum value of the atomic ratio of carbon is 5 at. %, And in the region of 90% or more in the thickness direction of the gas barrier layer, the atomic ratio of silicon, the atomic ratio of oxygen, and the atomic ratio of carbon satisfy the conditions represented by the above formula (1). It was confirmed.

(Reference Comparative Example A1)
On the surface of a biaxially stretched polyethylene naphthalate film (PEN film, thickness: 100 μm, width: 350 mm, manufactured by Teijin DuPont Films, Inc., trade name “Teonex Q65FA”), using a silicon target, in an oxygen-containing gas atmosphere, A gas barrier layer made of silicon oxide was formed by reactive sputtering to obtain a first film for comparison.

The thickness of the gas barrier layer in the obtained first film was 100 nm. The water vapor permeability of the obtained first film is 1.3 g / (m ² · day) under the conditions of a temperature of 40 ° C., a humidity of 10% RH on the low humidity side, and a humidity of 100% RH on the high humidity side. Its gas barrier properties were insufficient.

For the obtained first film, a silicon distribution curve, an oxygen distribution curve, a carbon distribution curve, and an oxygen carbon distribution curve were prepared by the same method as in Reference Example A1. The obtained silicon distribution curve, oxygen distribution curve and carbon distribution curve are shown in FIG. In addition, regarding the obtained silicon distribution curve, oxygen distribution curve, carbon distribution curve and oxygen-carbon distribution curve, the atomic ratio (atomic concentration) and the distance from the surface of the gas barrier layer as well as the relationship between the atomic ratio (atomic concentration) and etching time. The relationship with (nm) is also shown in the graph of FIG. “Distance (nm)” shown on the horizontal axis of the graph of FIG. 15 is a value obtained by calculation from the etching time and the etching rate. As is clear from the results shown in FIGS. 14 and 15, it was confirmed that the obtained carbon distribution curve did not have an extreme value.

As described below, an organic EL element was produced, and a light extraction structure was bonded thereto, and the relationship between the presence of the light extraction structure and the luminance was evaluated.

In each reference example, a current of 0.15 mA was passed through the organic EL element, and the emission intensity in the normal direction (front direction) at that time and the integration intensity using an integrating sphere were measured. A light emitting device having a glass substrate having a flat surface and an organic EL element provided on the glass substrate is used as a reference light emitting device, and the characteristics of the reference light emitting device and the characteristics of the light emitting devices of the respective reference examples are shown. Compared. Specifically, the light emission intensity and the integrated intensity in the front direction of the light emitting device of each reference example were respectively divided by the light emission intensity and the integrated intensity in the front direction of the reference light emitting device, and the value of each magnification was calculated. In the standard light-emitting device, a glass substrate having a flat surface corresponds to a virtual structure having a flat emission surface.

(Reference Example 1)
An anode made of an ITO thin film having a predetermined pattern shape was formed on a glass substrate having a flat surface, and this anode and the glass substrate were subjected to UV / O ₃ cleaning for 20 minutes. Next, a suspension of poly (3,4) ethylenedioxythiophene / polystyrene sulfonic acid (manufactured by Starck Vitech, trade name: BaytronP CH8000) was filtered in two stages. In the first stage filtration, a 0.45 μm diameter filter was used, and in the second stage filtration, a 0.2 μm diameter filter was used. The solution obtained by filtration was applied onto the anode by spin coating, and the coating film was heat-treated at 200 ° C. for 15 minutes on a hot plate in an air atmosphere to form a hole injection layer having a thickness of 65 nm. .

Next, a xylene solution having a concentration of 1.2 mass% of Lumation WP1330 (manufactured by SUMATION) was prepared. This solution was applied onto the hole injection layer by spin coating, and the coating film was heat-treated on a hot plate at 130 ° C. for 60 minutes in a nitrogen atmosphere to form a light emitting layer having a thickness of 65 nm.

Next, the substrate on which the light emitting layer was formed was introduced into a vacuum vapor deposition machine, and Ba and Al were sequentially deposited at a thickness of 5 nm and 80 nm, respectively, to form a cathode. The metal deposition was started after the degree of vacuum reached 1 × 10 ⁻⁴ Pa or less. Thereby, the organic EL element comprised from an anode, a positive hole injection layer, a light emitting layer, and a cathode was formed on the board | substrate.

A photocurable sealant is applied to the periphery of the sealing glass with a dispenser, the substrate on which the organic EL element is formed and the sealing glass are bonded together in a nitrogen atmosphere, and the photocurable sealant is cured with ultraviolet rays. By doing so, the organic EL element was sealed.

A film UTE12 (refractive index 1.5, thickness 188 μm) manufactured by MNtech having an uneven surface formed by a plurality of granular structures arranged in a dispersed manner was prepared as a light extraction structure. This film was bonded to a glass substrate using a non-carrier pressure-sensitive adhesive (refractive index 1.5). At that time, the film was bonded to the glass substrate so that the concavo-convex structure was disposed on the outermost surface.

FIG. 16 is a photomicrograph of the cross section of UTE12, and FIG. 17 is a photomicrograph of the surface of UTE12. As shown in FIGS. 16 and 17, the surface of the UTE 12 has a concavo-convex structure formed by a plurality of hemispherical granular structures.

The total light transmittance of UTE12 is 68.4%, haze is 82.6%, the diffusion parameter I (35) / I (70) is 7.2, and I (0) / I (35) is 1.7. Met. When comparing the light emitting device of this reference example with the standard light emitting device in which UTE12 is not bonded to the glass substrate, the front intensity (front luminance) of the light emitting device of this reference example is 1.43 times, and the integrated intensity Was 1.34 times.

<Measurement method of I (θ °)>
Although the definition of I (θ °) is as described above, a method of measuring I (θ °) actually measured in the reference example will be described with reference to FIG. As shown in FIG. 18, the angle formed with the normal of the main surface of the light extraction structure out of the light that enters the light extraction structure at an incident angle φ ° and exits from the light extraction surface (exit surface). Was measured every 5 ° in the range of ± 80 °. A halogen lamp SPH-100N manufactured by Chuo Seiki was used as a light source. When the light source is a planar light source, light having a specific incident angle does not enter the light extraction structure, but light of −90 ° <φ ° <90 ° simultaneously enters the light extraction structure. To simulate this, the outgoing light in the θ ° direction measured at each incident angle while changing the incident angle φ ° of the incident light by 5 ° in the range of −80 ° ≦ φ ° ≦ 80 °. I (θ °) was calculated by integrating the intensities.

(Reference Example 2)
In the same manner as in Reference Example 1, an organic EL element is formed on a glass substrate, and a film UTE21 (refractive index of 1.5) having a concavo-convex structure surface formed by a plurality of granular structures arranged in a dispersed manner is used. , Having a thickness of 188 μm) was prepared as a light extraction structure. This film was bonded to a flat surface opposite to the organic EL element of the glass substrate using a non-carrier adhesive (refractive index 1.5). In that case, the film was bonded to the glass substrate so that the uneven structure of the film was disposed on the outermost surface.

FIG. 19 is a micrograph of the surface of UTE21. As shown in FIG. 19, the surface of the UTE 21 has a concavo-convex structure formed by a plurality of hemispherical granular structures.

The total light transmittance of UTE21 is 63.4%, haze is 78.7%, diffusion parameter I (35) / I (70) is 8.4, and I (0) / I (35) is 2.0. Met. When comparing the light emitting device of this reference example with a standard light emitting device in which UTE21 is not bonded to the glass substrate, the front intensity (front luminance) of the light emitting device of this reference example is 1.45 times, and the integrated intensity Was 1.34 times.

(Reference Example 3)
In the same manner as in Reference Example 1, an organic EL element is formed on a glass substrate, and a wave front film WF80 (refractive index of 1.5 is formed) having a concavo-convex structure surface formed by a plurality of granular structures arranged in a dispersed manner. , Having a thickness of 80 μm) was prepared as a light extraction structure. This film was bonded to a flat surface opposite to the organic EL element of the glass substrate using a non-carrier adhesive (refractive index 1.5). In that case, the film was bonded to the glass substrate so that the uneven structure of the film was disposed on the outermost surface.

FIG. 20 is a photomicrograph of the surface of WF80. As shown in FIG. 20, the surface of WF80 has a concavo-convex structure formed by a plurality of granular structures.

WF80 has a total light transmittance of 75.1%, a haze of 89.3%, a diffusion parameter I (35) / I (70) of 6.5, and I (0) / I (35) of 1.1. Met. When comparing the light emitting device of this reference example with a standard light emitting device in which WF80 is not bonded to a glass substrate, the front intensity (front luminance) of the light emitting device of this reference example is 1.42 times, and the integrated intensity Was 1.31 times.

(Reference Example 4)
In the same manner as in Reference Example 1, an organic EL element was formed on a glass substrate, and a 3M film BEF100 (refractive index 1.5, thickness 150 μm) as a prism film was prepared as a light extraction structure. This film was bonded to a flat surface opposite to the organic EL element of the glass substrate using a non-carrier pressure-sensitive adhesive (refractive index: 1.5). In that case, the film was bonded to the glass substrate so that the uneven structure of the film was disposed on the outermost surface.

When comparing the light emitting device of this reference example with a standard light emitting device not bonded to the BEF100 glass substrate, the front intensity (front luminance) of the light emitting device of this reference example is 1.26 times, and the integrated intensity is 1. It was 25 times.

(Reference Example 5)
In the same manner as in Reference Example 1, an organic EL element is formed on a glass substrate, and a film opal PCM1 (refracted by Ewa Shoko Co., Ltd.) having an uneven surface formed by a plurality of granular structures arranged in a dispersed manner. A ratio of 1.5 and a thickness of 120 μm was prepared as a light extraction structure. This film was bonded to a flat surface opposite to the organic EL element of the glass substrate using a non-carrier pressure-sensitive adhesive (refractive index: 1.5). In that case, the film was bonded to the glass substrate so that the uneven structure of the film was disposed on the outermost surface.

PCM1 has a total light transmittance of 92.7%, a haze of 86.0%, a diffusion parameter I (35) / I (70) of 2.0, and I (0) / I (35) of 1. .3. When comparing the light emitting device of this reference example and the standard light emitting device not bonded to the PCM1 glass substrate, the front intensity (front luminance) of the light emitting device of this reference example is 1.24 times, and the integrated intensity is It was 1.26 times.

In summary, Reference Examples 1, 2, and 3 have higher light extraction efficiency than Reference Examples 4 and 5, and both front luminance and integrated intensity are 1.3 times or more than the standard light emitting device. It was.

As described above, the film used in the organic EL device according to the present invention has a sufficient gas barrier property, and even when bent, it can sufficiently suppress a decrease in the gas barrier property. is there.

DESCRIPTION OF SYMBOLS 1 2nd film 2 Organic EL element 3 Protective layer 4 Adhesive layer 5 Gas barrier layer 6 First film substrate 7 Second film substrate 8 Second gas barrier layer 11 First film 13 Organic EL device 14

Light extraction structure

500, 510, 520

Unwinding roll

511, 512

First laminating roll

521, 522

Second laminating roll

513, 523 Transport roll 530

Rewinding roll

610, 620

Coating device

611, 621 Curing device 701

Feeding roll

21, 22, 23, 24 Transport rolls 31, 32 A pair of film forming rolls 41 Gas supply pipe 51

Power source

61, 62 for generating plasma Magnetic field generator 701 Sending roll 702 Winding roll S Output surface

Claims

An organic EL element;
A first film disposed to face the organic EL element;
A light extraction structure disposed opposite to the organic EL element and having an emission surface for emitting light emitted from the organic EL element;
With
The first film has a gas barrier layer containing silicon atoms, oxygen atoms and carbon atoms,
From the ratio of the number of silicon atoms, the ratio of the number of oxygen atoms and the ratio of the number of carbon atoms to the total amount of silicon atoms, oxygen atoms and carbon atoms, and from one surface of the gas barrier layer in the thickness direction of the gas barrier layer A silicon distribution curve, an oxygen distribution curve, and a carbon distribution curve respectively representing the relationship with the distance of
(I) In the region of 90% or more in the thickness direction of the gas barrier layer, the ratio of the number of silicon atoms is the second among the ratio of the number of silicon atoms, the ratio of the number of oxygen atoms, and the ratio of the number of carbon atoms. Is a large value,
(Ii) the carbon distribution curve has at least one extreme value; and (iii) the difference between the maximum value and the minimum value of the ratio of the number of carbon atoms in the carbon distribution curve is 5 atomic% or more.
An organic EL device that satisfies the requirements.
Both the front intensity and the integrated intensity of the light that enters the light extraction structure from the surface opposite to the light exit surface and exits from the light exit surface are compared to when the light exit surface is planar. The organic EL device according to claim 1, wherein the emission surface has a concavo-convex structure that is 1.3 times or more.
A lighting device having the organic EL device according to claim 1.
A surface light source device having the organic EL device according to claim 1.
A display device comprising the organic EL device according to claim 1.