JP2017126611A - Light-emitting electrochemical element, and light-emitting device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting electrochemical element (i.e. LEC: light-emitting electrochemical cell) which enables the dramatic rise in the efficiency of light extraction from a light-emitting face, and a light-emitting device having the LEC, and to provide an LEC which makes possible to obtain white light emission extremely close to white at a high efficiency, and a light-emitting device having the LEC.SOLUTION: A light-emitting electrochemical element has a laminate structure comprising an optical substrate, a first electrode, a light-emitting layer, and a second electrode in this order. The light-emitting layer includes a particular conductive polymer, a polymer electrolyte and an electrolytic salt. At least one face of the light-emitting layer is bumpy in geometry. A light-emitting device comprises the light-emitting electrochemical element.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a light-emitting electrochemical element and a light-emitting device having the light-emitting electrochemical element.

In recent years, organic light-emitting diodes (OLEDs) are generally lightweight, thin and capable of forming a large-area light-emitting surface, and are expected to be used in various light-emitting devices such as lighting and displays. Has been.
This organic electroluminescent element is generally composed of an anode, a cathode, and a light emitting layer, and a light emitting layer includes holes injected from the anode by applying a voltage between both electrodes and electrons injected from the cathode. It emits light by combining with. In order to increase the luminous efficiency of the organic electroluminescent device, it is necessary to provide a hole injection layer or an electron injection layer for improving the recombination efficiency of holes and electrons in addition to the light emitting layer to form a multilayer structure. There is a problem that the structure becomes complicated and the manufacturing process becomes complicated. In addition, a high electric field is required for driving.

As an element that solves the problems of the organic electroluminescence element described above, a light-emitting electrochemical cell (LEC) has been proposed in, for example, Patent Document 1, Patent Document 2, and the like.
The LEC includes a first electrode, a second electrode, and a light emitting layer provided between the electrodes. The light emitting layer is formed by dispersing a conductive polymer, which is a light emitting material, and an electrolytic salt in an electrolyte. In this LEC, by applying a voltage between the two electrodes, a pn junction or a pin junction is formed by injection of positive and negative charges from the electrode and movement of both positive and negative ions of the supporting salt. It is presumed that electrons recombine on the light-emitting molecules in the light-emitting layer to excite the light-emitting molecules and emit light by deactivation from the excited state to the ground state.
This LEC generally has (1) low driving voltage, (2) use of stable electrodes in the atmosphere, and (3) manufacture of a device with a single light emitting layer compared to OLEDs. Therefore, it has advantages such as a simple element configuration. Among them, LEC using a solid electrolyte is particularly attracting attention because it is easy to seal at the time of device manufacture and has little influence on the environment when the device is damaged.

However, in a light-emitting element having a layer structure such as LEC, a part of the emitted light is confined in the element due to the difference in refractive index between the light-emitting layer and the transparent electrode on the light extraction side. There is a problem that the light extraction efficiency from the light emitting surface is low because the leakage from the side surface of the device to the outside occurs.
As a means for solving this problem, in order to increase the light extraction efficiency, for example, Patent Document 3 discloses, for example, an organic electroluminescence device in which a plurality of anode electrodes, organic electroluminescence layers, and cathode electrodes are laminated in this order on a transparent substrate. In a luminescence display element (OLED), an organic electroluminescence display element is disclosed in which random dot-like irregularities are formed on the transparent substrate.

JP 2008-291230 A Special table 2012-516033 gazette JP 2000-40584 A

  In the OLED as in Patent Document 3, since the organic layer can be formed in a vapor phase such as vapor deposition or sputtering, for example, when formed on a substrate having an uneven shape, the uneven shape of the substrate It is easy to form an uneven organic layer following the above. However, since the light emitting layer of LEC uses an electrolyte, it is necessary to form a solution containing a light emitting compound by a coating method in order to form an organic layer. When the coating method is used, even if an uneven organic layer that follows the uneven shape is formed on a substrate having an uneven shape, the organic layer is filled in the recess, and the uneven shape is smoothed. It is considered that it is difficult to form a concavo-convex shape with a depth. For this reason, it is considered that a short circuit occurs at the convex portion and an LEC having sufficient light extraction efficiency cannot be created.

Due to the above-described circumstances, the light extraction efficiency is not sufficient in the LEC in which the solution containing the light emitting compound is formed by the coating method with the gentle unevenness disclosed in Patent Document 3.
Accordingly, an object of the present invention is to provide an LEC capable of dramatically improving the light extraction efficiency from the light emitting surface and a light emitting device having the LEC. It is another object of the present invention to provide an LEC capable of obtaining white light emission that is almost as white as possible with high efficiency and a light emitting device having the LEC.

  As a result of intensive research on the above problems, the present inventors have succeeded in dramatically improving the light extraction efficiency by developing a LEC including a light emitting layer having a specific uneven shape on at least one side thereof, thereby completing the present invention. It came to. Furthermore, in addition to forming the uneven shape, an invention has been completed in which two specific types of conductive polymers are contained in the light emitting layer, whereby high-intensity white light is obtained with high efficiency at a low driving voltage.

That is, according to the present invention, in the light emitting electrochemical device having a laminated structure in the order of the optical substrate, the first electrode, the light emitting layer, and the second electrode, the light emitting layer contains a conductive polymer, a polymer electrolyte, and an electrolytic salt. And the light emitting electrochemical element whose at least one surface of the said light emitting layer is uneven | corrugated shape is provided.
In the light emitting electrochemical device of the present invention, when white light is obtained, the conductive polymer is composed of at least a conductive polymer A and a conductive polymer B, and the highest of the conductive polymer A and the conductive polymer B. The absolute value of the energy difference between the occupied orbits (HOMO) or the lowest unoccupied orbit (LUMO) is 0.5 eV or less.
Furthermore, according to another viewpoint of this invention, it has the voltage part which applies a voltage between the 1st electrode of the said light emitting electrochemical element, and this light emitting electrochemical element, and a 2nd electrode, The light emitting device characterized by the above-mentioned. Is provided.

The light-emitting electrochemical element of the present invention can obtain high luminance with high efficiency at a low driving voltage by forming at least one surface of the light-emitting layer to have an uneven shape.
In the light emitting electrochemical device of the present invention, the LEC containing two kinds of conductive polymers having specific light emitting characteristics in the light emitting layer has a low driving voltage, high luminance, and white light emission that is almost infinitely white. Can be obtained with high efficiency. In the present application, white as close as possible to white means that x and y are in the range of 0.33 ± 0.09 in the chromaticity diagram. The emission color of the light-emitting electrochemical element of the present invention and the compound related to the element is applied to the CIE chromaticity coordinates based on the result of measurement using “instant multi-photometry system (wide dynamic range type) MCPD9800” (manufactured by Otsuka Electronics Co., Ltd.). The color when In addition, hereinafter, a thing with such a favorable whiteness may be called high whiteness.
In addition, by using a light emitting device using the light emitting electrochemical element of the present invention, a highly efficient light emitting device capable of obtaining white light with high brightness and high whiteness can be obtained.

It is a schematic sectional drawing of the optical board | substrate which concerns on one Embodiment of the light emitting electrochemical element of this invention. It is a figure which shows the planar view analysis image of the uneven | corrugated shape of an optical board | substrate or a light emitting layer. 1 is a schematic cross-sectional view of a light-emitting electrochemical device according to an embodiment of the present invention. It is the schematic explaining the determination method of the extending | stretching form A and B of an uneven | corrugated shaped convex part (white part). It is a figure for demonstrating the manufacturing process of an optical board | substrate. It is a figure which shows the unevenness | corrugation analysis image which analyzed the uneven | corrugated shape of the uneven structure layer 3 of the optical substrate 1 of Example 1 by AFM, and its Fourier transform image. (B) is an enlarged version of (a), and (a) and (b) both show Fourier transform images. It is a figure which shows the uneven | corrugated analysis image which analyzed the uneven | corrugated shape of the light emitting layer 5 of the element (1) produced in Example 1 by AFM, and its Fourier transform image. (B) is an enlarged version of (a), and (a) and (b) both show Fourier transform images. It is a figure which shows transition of the current efficiency (cd / A) at the time of the light emission performance measurement in Example 1 and Comparative Example 1. 6 is a schematic cross-sectional view of an element (3) manufactured in Comparative Example 1. FIG.

Hereinafter, the present invention will be described in detail.
The light emitting electrochemical device of the present invention has a laminated structure in which an optical substrate, a first electrode, a light emitting layer, and a second electrode are laminated in this order. The light emitting layer contains a conductive polymer, a polymer electrolyte, and an electrolytic salt, and at least one surface of the light emitting layer has an uneven shape.
In the light-emitting electrochemical element of the present invention, the conductive polymer may be one type, but when emitting white light, it is composed of two types of conductive polymer A and conductive polymer B. The absolute value of the energy difference between the highest occupied orbit (HOMO) or the lowest unoccupied orbit (LUMO) between the conductive polymer A and the conductive polymer B is 0.5 eV or less.
In the light-emitting electrochemical element of the present invention, when a voltage is applied between the first electrode and the second electrode, the conductive polymer emits light in blue to blue-green or red to red-orange. Further, when the conductive polymer A and the conductive polymer B are used as the conductive polymer, the conductive polymer A emits blue to blue green light, and the conductive polymer B emits red to red orange light to emit white light. Alternatively, the conductive polymer A emits blue to blue-green light, the conductive polymer B emits red to red-orange light, and the exciplex formed by the conductive polymer A and / or the conductive polymer B emits fluorescence to emit white light. Emits light. The exciplex is an excimer formed by the conductive polymer A or the conductive polymer B, and an exciplex or an electroplex formed between the conductive polymer A and the conductive polymer B. The excimer fluorescence and the exciplex fluorescence are respectively used. Alternatively, electroplex fluorescence is emitted. When at least one surface of the light emitting layer is uneven, white light can be extracted with high efficiency.

An excimer, exciplex or electroplex is an excited dimer consisting of the same or different types of atoms or molecules, where the excited state atoms or molecules bind to the same or other types of ground state atoms or molecules. Is formed. Excimer fluorescence, exciplex fluorescence or electroplex fluorescence is fluorescence emitted when an excited excimer, exciplex or electroplex is deactivated.
An exciplex in a light-emitting electrochemical element is an excited dimer formed from a donor molecule in which holes are injected into HOMO and an acceptor molecule in which electrons are injected into LUMO. Electron and hole delocalization is occurring. In the light emission process, electrons and holes in the excited dimer recombine to emit light.
In addition, in the electroplex, the overlap of the wave function between the donor molecule in which holes are injected into HOMO and the acceptor molecule in which electrons are injected into LUMO is small, and delocalization of charges hardly occurs. Therefore, light emission occurs by direct electronic transition from the LUMO of the acceptor molecule to the HOMO of the donor molecule.

The optical substrate of the present invention is not particularly limited as long as it can be used for a light-emitting electrochemical element, and a known substrate may be used. FIG. 1 shows an example of a preferable optical substrate. The optical substrate 1 is a laminate of the support substrate layer 2 and the concavo-convex structure layer 3, and the concavo-convex structure layer 3 is a substrate having a concavo-convex shape on the surface not in contact with the support substrate layer 2. It is preferable that the extending direction of the concavo-convex convex portions is irregularly distributed in plan view. That is, it is preferable that the concavo-convex shape is formed so that the direction of undulation due to the concavo-convex becomes irregular. The optical substrate of the present invention is preferably the optical substrate 1 of FIG. 1, but is not limited to this, and does not have the uneven structure layer 3 but only the support substrate layer 2, that is, has an uneven shape. It may not be.
Further, the thickness of the optical substrate varies depending on the size of the target LEC, and is not particularly limited. However, the size of the LEC and the thickness of the light emitting layer and the electrode are between 1 μm and 1 cm. A suitable thickness may be set according to the thickness. In addition, since the depth of the unevenness is very small as compared with the thickness of the optical substrate, it is not necessary to consider the influence of the unevenness on the thickness.

  Examples of the supporting substrate layer 2 include substrates made of inorganic materials such as glass, quartz, and silicon substrates, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP), and polymethyl. Resin substrates such as methacrylate (PMMA), polystyrene (PS), polyimide (PI), and polyarylate can be used. In order to extract emitted light from the optical substrate 1 side, the support substrate layer 2 is preferably transparent.

In order to improve the adhesiveness with the concavo-convex structure layer 3, the surface side of the support substrate layer 2 in contact with the concavo-convex structure layer 3 may be surface-treated or an easy-adhesion layer may be provided. In addition, a gas barrier layer may be provided on the surface of the support substrate layer 2 opposite to the surface in contact with the concavo-convex structure layer 3 for the purpose of preventing intrusion of gases such as moisture and oxygen.
Further, the optical substrate 1 has a lens structure having various optical functions such as condensing and light diffusion on the surface opposite to the surface in contact with the concavo-convex structure layer 3 of the supporting substrate layer 2, and condensing and light diffusion. Other optical functional layers having various optical functions may be provided.

As the concavo-convex structure layer 3, for example, silica, a Ti-based material, an ITO (indium tin oxide) -based material, a sol-gel material such as ZnO, ZrO ₂ , and Al ₂ O ₃ can be used. For example, when the uneven structure layer 3 made of silica is formed on the support substrate layer 2 by a sol-gel method, a metal alkoxide (silica precursor) sol-gel material is prepared as a base material. As precursors of silica, tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), tetra-i-propoxysilane, tetra-n-propoxysilane, tetra-i-butoxysilane, tetra-n-butoxysilane, tetra- Tetraalkoxide monomers typified by tetraalkoxysilane such as sec-butoxysilane, tetra-t-butoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isopropyltrimethoxysilane, phenyltrimethoxysilane, Methyltriethoxysilane (MTES), ethyltriethoxysilane, propyltriethoxysilane, isopropyltriethoxysilane, phenyltriethoxysilane, methyltripropoxysilane, ethyltripro Xysilane, propyltripropoxysilane, isopropyltripropoxysilane, phenyltripropoxysilane, methyltriisopropoxysilane, ethyltriisopropoxysilane, propyltriisopropoxysilane, isopropyltriisopropoxysilane, phenyltriisopropoxysilane, tolyltriethoxy Trialkoxide monomers represented by trialkoxysilanes such as silane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldiisopropoxysilane, dimethyldi-n-butoxysilane, dimethyldi-i-butoxysilane, dimethyldi -Sec-butoxysilane, dimethyldi-t-butoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, die Ludipropoxysilane, diethyldiisopropoxysilane, diethyldi-n-butoxysilane, diethyldi-i-butoxysilane, diethyldi-sec-butoxysilane, diethyldi-t-butoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane, di Propyl dipropoxysilane, dipropyldiisopropoxysilane, dipropyldi-n-butoxysilane, dipropyldi-i-butoxysilane, dipropyldi-sec-butoxysilane, dipropyldi-t-butoxysilane, diisopropyldimethoxysilane, diisopropyldiethoxysilane, diisopropyl Dipropoxysilane, diisopropyldiisopropoxysilane, diisopropyldi-n-butoxysilane, diisopropyldi-i-butoxysilane, diisopropyl Lopyldi-sec-butoxysilane, diisopropyldi-t-butoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldipropoxysilane, diphenyldiisopropoxysilane, diphenyldi-n-butoxysilane, diphenyldi-i-butoxysilane Dialkoxide monomers typified by dialkoxysilanes such as diphenyldi-sec-butoxysilane and diphenyldi-t-butoxysilane can be used. Furthermore, alkyltrialkoxysilanes or dialkyldialkoxysilanes in which the alkyl group has C _{4 to} C ₁₈ carbon atoms can also be used. Monomers having a vinyl group such as vinyltrimethoxysilane and vinyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxy Monomers having an epoxy group such as silane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, monomers having a styryl group such as p-styryltrimethoxysilane, 3-methacryloxypropylmethyl Monomers having a methacrylic group such as dimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropiyl Monomers having an acrylic group such as trimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltri Monomers having amino groups, such as methoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, Monomers having a ureido group such as 3-ureidopropyltriethoxysilane, monomers having a mercapto group such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane, sulfs such as bis (triethoxysilylpropyl) tetrasulfide A monomer having an alkyl group, a monomer having an isocyanate group such as 3-isocyanatopropyltriethoxysilane, a polymer obtained by polymerizing a small amount of these monomers, a composite material characterized by introducing a functional group or a polymer into a part of the material, etc. The metal alkoxides may be used. In addition, some or all of the alkyl group and phenyl group of these compounds may be substituted with fluorine. Furthermore, metal acetylacetonate, metal carboxylate, oxychloride, chloride, a mixture thereof and the like can be mentioned, but not limited thereto. Examples of the metal species include, but are not limited to, Ti, Sn, Al, Zn, Zr, In, and a mixture thereof in addition to Si. What mixed suitably the precursor of the said metal oxide can also be used. Furthermore, a silane coupling agent having a hydrolyzable group having affinity and reactivity with silica and an organic functional group having water repellency can be used as a precursor of silica. For example, silane monomers such as n-octyltriethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane, vinylsilane such as vinylmethyldimethoxysilane, Methacrylic silane such as 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycyl Epoxy silanes such as Sidoxypropyltriethoxysilane, 3-Mercaptopropyltrimethoxysilane, Mercaptosilanes such as 3-Mercaptopropyltriethoxysilane, 3-Octanoylthio-1-pro Sulfur silane such as rutriethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl)- Examples include aminosilanes such as 3-aminopropylmethyldimethoxysilane and 3- (N-phenyl) aminopropyltrimethoxysilane, and polymers obtained by polymerizing these monomers.

  When a mixture of TEOS and MTES is used as the sol-gel material solution, the mixing ratio can be 1: 1, for example, in a molar ratio. When this sol-gel material is used, amorphous silica is produced by performing hydrolysis and polycondensation reactions. In order to adjust the pH of the solution as a synthesis condition, an acid such as hydrochloric acid or an alkali such as ammonia is added. Further, a material that generates an acid or an alkali by irradiation with light such as ultraviolet rays may be added. The pH may be 4 or less, or 10 or more. Water may also be added to perform the hydrolysis. The amount of water to be added can be 1.5 times or more in molar ratio with respect to the metal alkoxide species.

  Solvents for the sol-gel material solution include, for example, alcohols such as methanol, ethanol, isopropyl alcohol (IPA) and butanol, aliphatic hydrocarbons such as hexane, heptane, octane, decane and cyclohexane, benzene, toluene, xylene, mesitylene and the like Aromatic hydrocarbons, diethyl ether, tetrahydrofuran, dioxane and other ethers, acetone, methyl ethyl ketone, isophorone, cyclohexanone and other ketones, butoxyethyl ether, hexyloxyethyl alcohol, methoxy-2-propanol, benzyloxyethanol, etc. Ether alcohols, glycols such as ethylene glycol and propylene glycol, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, Glycol ethers such as lenglycol monomethyl ether acetate, esters such as ethyl acetate, ethyl lactate and γ-butyrolactone, phenols such as phenol and chlorophenol, N, N-dimethylformamide, N, N-dimethylacetamide, N- Examples thereof include amides such as methylpyrrolidone, halogen-based solvents such as chloroform, methylene chloride, tetrachloroethane, monochlorobenzene and dichlorobenzene, hetero-containing compounds such as carbon disulfide, water, and mixed solvents thereof. Further, ethanol and isopropyl alcohol may be used, or ethanol and isopropyl alcohol may be mixed with water.

  Examples of additives for the sol-gel material solution include polyethylene glycol, polyethylene oxide, hydroxypropyl cellulose, polyvinyl alcohol for viscosity adjustment, alkanolamines such as triethanolamine which are solution stabilizers, β-diketones such as acetylacetone, β- Ketoester, formamide, dimethylformamide, dioxane and the like can be used.

  Further, as the concavo-convex structure layer 3, a resin can also be used. Examples of the curable resin include photo-curing resins, thermosetting resins, moisture-curing resins, and chemical-curing resins (two-component mixing). Specifically, epoxy, acrylic, methacrylic, vinyl ether, oxetane, urethane, melamine, urea, polyester, polyolefin, phenol, cross-linkable liquid crystal, fluorine, silicone, polyamide And various resins.

  Hydrophobic treatment may be performed on the uneven surface of the uneven structure layer 3. A known method can be used as a method for the hydrophobization treatment. For example, if the surface of the concavo-convex structure layer 3 is a silica surface, it may be hydrophobized with dimethyldichlorosilane, trimethylalkoxysilane or the like, or hydrophobized with a trimethylsilylating agent such as hexamethyldisilazane and silicone oil. The surface treatment method of the metal oxide powder using supercritical carbon dioxide may be used. By making the surface of the concavo-convex structure layer 3 hydrophobic, when the optical substrate 1 is used for manufacturing a light-emitting electrochemical element, moisture can be easily removed from the optical substrate 1 in the manufacturing process of the element, and the light-emitting electrochemical element It is possible to prevent the occurrence of defects and deterioration. In addition, a gas barrier layer may be provided on the concavo-convex surface of the concavo-convex structure layer 3 for the purpose of preventing the entry of gas such as moisture and oxygen.

  The concavo-convex structure layer 3 is formed by applying the solution or resin of the sol-gel material prepared as described above onto the support substrate layer 2 and further transferring the concavo-convex pattern of the mold for transferring the concavo-convex pattern. The manufacturing process for transferring the uneven pattern to the uneven pattern transfer mold and the uneven structure layer 3 will be described later.

Next, the uneven surface of the uneven structure layer 3 will be described. In order to analyze the uneven shape, a scanning probe microscope (SPM) such as an atomic force microscope (AFM) can be used. In the present embodiment, by using a scanning probe microscope (for example, product name “E-sweep” manufactured by Hitachi High-Tech Science Co., Ltd.), the concavo-convex shape of the concavo-convex structure layer 3 is analyzed under the following analysis conditions. It is assumed that an unevenness analysis image and a planar view analysis image are obtained. In this specification, the average value of the uneven depth distribution defined below, the standard deviation of the uneven depth, the average depth of the unevenness, and the average pitch of the unevenness are as follows regardless of the material of the uneven structure layer 3 It can be determined by various analysis conditions and measurement methods.
<Analysis conditions>
Measuring method: Cantilever intermittent contact method Cantilever material: Silicon Cantilever lever width: 40μm
Cantilever tip tip diameter: 10 nm

A specific example of the analysis of the uneven shape will be described. By using E-sweep, an arbitrary 3 μm square (3 μm in length, 3 μm in width) or 10 μm square (10 μm in length, 10 μm in width) is measured under the above-described conditions to obtain an unevenness analysis image. At that time, the depth of unevenness at the measurement points of 16384 points (128 vertical points × 128 horizontal points) or more in the measurement region is obtained on a nanometer scale. The number of measurement points varies depending on the type and setting of the SPM to be used. In the case of E-sweep, measurement of 65536 points (256 vertical points × 256 horizontal points) within a measurement area of 3 μm square or 10 μm square (256 × 256 pixels). Measurement at a resolution of 1).
The unevenness analysis image may be subjected to flat processing including first-order inclination correction in order to increase measurement accuracy. Moreover, in order to ensure sufficient measurement accuracy in various analyzes related to the uneven shape described below, the measurement region has a length of 15 times or more of the average value of the widths of the convex portions included in the measurement region. It is preferable to use a square region with a length of.

  Specifically, the uneven depth can be measured as follows. First, of all the measurement points, the measurement point P having the highest height from the interface between the support substrate layer 2 and the concavo-convex structure layer 3 is determined. A plane including the measurement point P and parallel to the interface is determined as a reference plane (horizontal plane), and a depth value from the reference plane is calculated as the unevenness depth. The depth value from the reference plane may be, for example, a difference obtained by subtracting the height from the interface at each measurement point from the height value from the interface at the measurement point P. Such unevenness depth can be calculated and calculated automatically by software in E-sweep, for example.

  Thus, after calculating | requiring the uneven | corrugated depth in all the measurement points, the value which can be calculated by calculating | requiring the arithmetic mean and standard deviation is employ | adopted as the average value of uneven | corrugated depth distribution, and the standard deviation of uneven | corrugated depth, respectively. .

Specifically, the average value (m) of the uneven depth distribution is calculated by the following formula (I).
[In formula (I), m indicates the average value of uneven depth distribution, the total number of N measuring points, the irregularity depth of the x _i is the i-th measurement point. ]

Further, the standard deviation (σ) of the unevenness depth is calculated by the following equation (II).
[In the formula (II), sigma is the standard deviation of the unevenness depth, the total number of N measuring points, x _i is the i th measuring point of the uneven depth, m is an average value of uneven depth distribution. ]

  The convex part and concave part of this invention are defined using the average value of the uneven | corrugated depth distribution calculated above. That is, a region where the unevenness depth is equal to or greater than the average value of the unevenness depth distribution is defined as a convex portion, and a region where the unevenness depth is less than the average depth of the unevenness is defined as a recessed portion. For example, the unevenness analysis image is processed so that the convex portions are displayed in white and the concave portions are displayed in black, whereby a plan view analysis image (monochrome image) as shown in FIG. 2 is obtained. FIG. 2 is a diagram illustrating an example of a planar view analysis image of the measurement region in the optical substrate 1 according to the present embodiment. Hereinafter, when the uneven shape is described, the convex portion may be referred to as a white portion and the concave portion may be referred to as a black portion.

  The average depth of the unevenness is the difference between the depths of the protrusions and the recesses on the surface of the uneven structure layer 3 on which the unevenness is formed (the distance in the depth direction between the tops of the adjacent protrusions and the bottoms of the recesses). ) Is the average depth difference. The average depth of such irregularities is calculated by measuring 100 or more distances in the depth direction between the top of any adjacent convex part and the bottom of the concave part in the concave / convex analysis image, and calculating the arithmetic average thereof. it can.

  The average pitch of the unevenness is the pitch of the unevenness when the pitch of the unevenness on the surface of the uneven structure layer 3 on which the unevenness is formed (the interval between the tops of the adjacent protrusions or the bottoms of the adjacent recesses). It means the average value of. The average value of the pitch of such irregularities is obtained by measuring the interval between the tops of any adjacent convex portions or the bottom portions of adjacent concave portions in the above-described concave / convex analysis image, and obtaining the arithmetic average thereof. It can be calculated.

The average depth of the irregularities is preferably in the range of 30 to 300 nm, more preferably in the range of 40 to 200 nm. Moreover, as an average pitch of an unevenness | corrugation, the range of 100-1500 nm is preferable, for example, and the range of 200-1200 nm is more preferable. The average value of the uneven depth distribution is preferably in the range of 20 to 200 nm, more preferably in the range of 30 to 150 nm. The standard deviation of the concavo-convex depth is preferably in the range of 10 to 100 nm, and more preferably in the range of 15 to 75 nm.
This is because when the light emitting layer is formed reflecting the uneven shape of the optical substrate 1, the light extraction efficiency is improved when the uneven shape range of the light emitting layer is within these ranges.

Further, the width of the convex portion refers to the width of the convex portion (white display portion) of the planar view analysis image. Specifically, taking FIG. 2 as an example, the width of the white portion observed as an irregularly stretched string in FIG. 2 is defined as the width of the convex portion.
For the average value of the widths of the convex portions, arbitrary 100 or more locations are selected from the convex portions of the planar view analysis image, and in each of the directions substantially orthogonal to the extending direction of the convex portions in a plan view. It can be calculated by measuring the length from the boundary of the convex part to the boundary on the opposite side and calculating the arithmetic average thereof. In addition, although the branch part also exists in the said string-like white part, the said branch part is not used as the measurement location for calculating | requiring the average value of the width | variety of a convex part.
In addition, the average value of the width | variety of a convex part is about about half of the average pitch of an unevenness | corrugation.

Furthermore, the uneven surface of the uneven structure layer 3 can be identified by a Fourier transform image.
In the optical substrate 1, when a concavo-convex analysis image obtained by analyzing the concavo-convex shape formed on the surface of the concavo-convex structure layer 3 with a scanning probe microscope is subjected to a two-dimensional fast Fourier transform process to obtain a Fourier transform image, The Fourier transform image shows a circular or annular pattern whose center is the origin where the absolute value of the wave number is 0 μm ⁻¹ , and the absolute value of the wave number is 10 μm. ^-1 (may be in the range of 0.667～10Myuemu ^-1, further also may be within the range of 0.833～5Myuemu ^-1) may be present in a range within become within the region of. By forming a concavo-convex shape on the surface of the concavo-convex structure layer 3 so as to satisfy the above conditions (hereinafter referred to as “FFT conditions”), the wavelength dependency and directivity (property of emitting light strongly in a certain direction) of light emission are obtained. It can be reduced sufficiently.

The “circular or annular pattern of the Fourier transform image” is a pattern observed when bright spots are gathered in the Fourier transform image. Therefore, “circular shape” here means that the pattern of bright spots gathers appears to be almost circular, and includes the concept that part of the outer shape appears to be convex or concave. It is. In addition, “annular” means that a pattern of bright spots gathers appears to be almost circular, and includes those in which the shape of the outer circle and inner circle appear to be almost circular. It is a concept including what appears to be a convex shape or a concave shape of a part of the outer shape of the outer circle and the inner circle. Further, the pattern of "circular or annular, the absolute value of wavenumber 10 [mu] m ^-1 or less (may be in the range of 0.667～10Myuemu ^-1, may be further within the scope of 0.833～5Myuemu ^-1 ”Exists in a region within the range of“) ”means that 30% or more of the luminescent spots constituting the Fourier transform image have an absolute wave number of 10 μm ⁻¹ or less (0.667 to 10 μm ^−1). Or within the range of 0.833 to 5 μm ⁻¹ ).

  In addition, the following is known about the relationship between the pattern of the concavo-convex structure and the Fourier transform image. If the concavo-convex structure itself has no distribution or directivity in the pitch, the Fourier transform image also appears as a random pattern (no pattern), but the concavo-convex structure is isotropic in the XY direction as a whole, but the distribution is in the pitch. In some cases, a circular or annular Fourier transform image appears. Further, when the concavo-convex structure has a single pitch, the ring appearing in the Fourier transform image tends to be sharp.

  The Fourier transform image is analyzed by analyzing the shape of the unevenness formed on the surface of the uneven structure layer 3 using a scanning probe microscope (for example, product name “E-sweep” manufactured by Hitachi High-Tech Science Co., Ltd.). After obtaining the image, it is obtained by subjecting the unevenness analysis image to a two-dimensional fast Fourier transform process. The two-dimensional fast Fourier transform processing of the unevenness analysis image can be easily performed by electronic image processing using a computer equipped with two-dimensional fast Fourier transform processing software.

  As shown in FIG. 3, the light-emitting electrochemical device 100 of the present invention has a laminated structure in which an optical substrate 1, a first electrode 4, a light-emitting layer 5, and a second electrode 6 are laminated in this order. The optical substrate 1 is preferably the optical substrate 1 shown in FIG. 1 having the concavo-convex structure layer described above. This is because it is suitable for forming a concavo-convex shape on the surface of the light emitting layer 5 in correspondence with the concavo-convex shape on the surface of the optical substrate 1 (uneven structure layer 3).

The light emitting layer 5 according to the present invention has an uneven shape on at least one side (FIG. 3).
The calculation method of the average value of the uneven depth distribution and the standard deviation of the uneven depth related to the light emitting layer 5, and the uneven shape such as the average depth of the unevenness, the average pitch of the unevenness, and the extending direction of the protruding portions are the optical substrate. This is the same as the calculation method and the uneven shape described in 1. Moreover, it is preferable that the extending direction of the concavo-convex convex portion of the light emitting layer 5 is also irregularly distributed in a plan view.
From the viewpoint of easy formation of the uneven shape, it is preferable that the optical substrate 1 has an uneven shape, and the uneven shape of the light emitting layer 5 is formed in a shape corresponding to the uneven shape. Therefore, the light emitting layer 5 preferably has an uneven shape on both sides thereof as shown in FIG. The analysis of the uneven shape is performed in the same manner as in the case of the optical substrate 1. Moreover, FIG. 2 can also be illustrated as a planar view analysis image of the uneven shape of the light emitting layer 5.

From the viewpoint of light extraction efficiency, it is preferable that the stretched form of the white portion observed in an irregularly stretched string shape of the light emitting layer 5 illustrated in FIG. 2 satisfies the conditions described below.
In the case where the stretched part of the white part is divided by a length that is π (circumferential ratio) times the average value of the width of the white part (convex part), the stretched part is divided into a plurality of parts, and between the end points of the section The form in which the ratio of the linear distance between the two end points to the length of the contour line is 0.75 or less is referred to as a stretched form A. On the other hand, a form in which the ratio is greater than 0.75 is defined as a stretched form B.
In the case of dividing the extending portion of the white portion, for example, the white portion may be divided for each “π times the average value of the width of the white portion”, starting from one end point of the white portion. At this time, when another end point is reached and the last break is less than the π times, the break is not used for the determination of the stretching mode. In the case of a white portion having a branch (for example, a three-way), one direction is selected and divided. For directions that are not selected, a new “separation every π times” may be performed in the directions that are not selected, starting from the branching portion.

Hereinafter, with reference to FIG. 4, the determination method of the extending | stretching form A and B is demonstrated. In FIG. 4, for convenience, the concave portions are not shown in black, but the region S1 is a white portion (convex portion) and the region S2 is a concave portion.
Since the white portion has a width, the length of the contour line differs depending on the setting position of the contour line, but the shortest line in the section is defined as the contour line. If it demonstrates in FIG. 4, it is a line shown by X. FIG. In FIG. 4, when the starting point is a and the end point is b, La is π times the average value of the width of the white portion, and Lb represents the linear distance of the section ab. The case where the value of Lb / La is 0.75 or less is determined as the stretched form A, and the case where it exceeds 0.75 is determined as the stretched form B. The example illustrated in FIG.
Thus, the section of the white portion for determining the stretching form is arbitrarily selected as 100 sections, and it is determined which of the stretching forms A and B is. The ratio of the stretched form B is preferably 50% or more from the viewpoint of light extraction efficiency. More preferably, the ratio of the stretched form B is 50% or more and 80% or less. Since it is difficult to secure the 100 sections with one white portion, normally, a plurality of white portions are arbitrarily selected and divided as described above, and the 100 sections are selected.

  In the case where the concavo-convex shape of the light-emitting layer 5 is formed by a method of forming the concavo-convex shape on the optical substrate 1 and reflecting the concavo-convex pattern, which will be described in the manufacturing method described later, even in the concavo-convex shape of the optical substrate 1, the extended form The ratio of B is preferably 50% or more, and more preferably 50% or more and 80% or less. This is because the ratio is reflected in the uneven shape of the light emitting layer 5.

Next, a light emitting compound responsible for light emission of the light emitting layer will be described.
The light emitting layer of the present invention contains a conductive polymer as a light emitting compound. When emitting white light, it contains conductive polymer A and conductive polymer B, and is between the highest occupied orbit (HOMO) or lowest empty orbit (LUMO) of conductive polymer A and conductive polymer B. The absolute value of the energy difference is 0.5 eV or less. Thus, by reducing the absolute value of the energy difference between the highest occupied orbits (HOMO) or the lowest unoccupied orbit (LUMO), light emission from both can be obtained. When the absolute value of the energy difference exceeds 0.5 eV, light emission of only one of the conductive polymer A or the conductive polymer B, or formed between the conductive polymer A and the conductive polymer. Only the exciplex, or the electroplex, or only the exciplex and the electroplex, may emit light far from white light emission.
Further, in order to obtain white light emission, it is preferable that the light emission of the conductive polymer A and the conductive polymer B satisfy a complementary color relationship, but it is extremely difficult to find a compound having a complementary color relationship. In some cases, good white light emission cannot be obtained.
Therefore, in the present invention, the conductive polymer A and the conductive polymer B emit light by themselves, and the exciplex formed by the conductive polymer A and / or the conductive polymer B emits light with a complementary fluorescent color. By designing so as to be able to add new fluorescence that is complementary to the light emission by the conductive polymer A and the conductive polymer B, it is possible to obtain good white light emission. .
In addition, the conductive polymer A of the present invention has an electron and / or hole transport function, and is a conductive polymer that can efficiently transport electrons and / or holes. Among these, a conductive polymer or copolymer having a fluorene skeleton is preferable in that it excites good excimer fluorescence or exciplex fluorescence between the conductive polymers A or in combination with the conductive polymer B. A polymer or copolymer having a fluorene skeleton emits blue light by itself, forms excimers with conductive polymers A to emit excimer fluorescence, or forms exciplex with conductive polymers B to emit exciplex fluorescence. You can do it. The conductive polymer B can also emit light itself.

As the conductive polymer A having the fluorene skeleton, a conductive polymer represented by the following formula (1) is preferable. This is because white light with high whiteness can be obtained.
[In Formula (1), R is a C1-C20 alkyl group, m shows a polymerization degree, 5 or more, Preferably it is 10 or more, More preferably, it represents an integer of 20 or more. ]

Examples of the conductive polymer having the fluorene skeleton of the above formula (1) include the following.
Poly (9,9-di-n-hexylfluorenyl-2,7-diyl) of the following formula (1a):
[In the formula (1a), n represents the degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

Poly [9,9-bis- (2-ethylhexyl) -9H-fluorene-2,7-diyl] of the following formula (1b).

[In the formula (1b), n represents the degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

Poly (9,9-di-n-octylfluorenyl-2,7-diyl) of the following formula (1c):
[In the formula (1c), n represents the degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

Poly (9,9-di-n-dodecylfluorenyl-2,7-diyl) of the following formula (1d):
[In the formula (1d), n represents the degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

There is no particular upper limit on the degree of polymerization of the conductive polymer A as long as a light emitting layer can be formed. A light emitting layer composition can be prepared, and the light emitting layer can be formed by melting or dissolving the composition in a solvent. Any degree of polymerization may be used.
As the conductive polymer A having the fluorene skeleton, poly (9,9-di-n-dodecylfluorenyl-2,7-diyl) represented by the formula (1d) is more preferable. This is because white light with higher whiteness can be obtained.

Next, the conductive polymer B contained in the light emitting layer of the present invention will be described.
The conductive polymer B is not particularly limited as long as it forms an exciplex or electroplex with the conductive polymer A. However, when a voltage is applied, the conductive polymer B plays a role in efficiently transporting holes. To fulfill.

  As the conductive polymer B, a polymer or copolymer having a phenylene vinylene skeleton or a polymer or copolymer having a thiophene skeleton represented by the following formulas (2), (3), and (4) has high hole mobility and efficiency. It is preferable in that excitons can be formed well and white light with high whiteness can be obtained.

[In the formula (2), W represents the degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

[In Formula (3), X represents a degree of polymerization and represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more. ]

[In Formula (4), Y and Z represent the degree of polymerization, and each independently represents an integer of 5 or more, preferably 10 or more, more preferably 20 or more, and may be the same or different. ]

There is no particular upper limit on the degree of polymerization of the conductive polymer B as long as a light emitting layer can be formed. A light emitting layer composition can be prepared, and the light emitting layer can be formed by melting or dissolving the composition in a solvent. Any degree of polymerization may be used.
Specific examples of the conductive polymer B include poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylenevinylene], poly [2-methoxy-5- (3 ′, 7′-dimethyl). Octyloxy) -1,4-phenylenevinylene], poly [3-octylthiophene-2,5-diyl-co-3-decyloxythiophene-2,5-diyl] (POT-co-DOT), etc. Can do.

When emitting white light, the absolute value of the energy difference between the highest occupied orbit (HOMO) or the lowest empty orbit (LUMO) between the conductive polymer A and the conductive polymer B is 0.5 eV, more preferably Both conductive polymers are selected so as to be 0.3 eV or less. Moreover, such an energy difference should just have either between HOMO or LUMO, and both may be such an energy difference.
By selecting the energy difference between HOMO or LUMO of both conductive polymers in this way, there is an effect that charges are easily injected into both conductive polymers, and light emission from both conductive polymers can be easily obtained. There is an advantage.

  The content ratio of the conductive polymer A and the conductive polymer B is preferably 1 to 200 parts by weight, more preferably 5 to 120 parts by weight, with respect to 100 parts by weight of the conductive polymer A. preferable. The lower limit is more preferably 10 parts by weight or more. If it is in the said range, more favorable fluorescence light emission will be obtained, luminous efficiency can be made more favorable, and it will become white light of high whiteness. Furthermore, since it becomes easy to form an exciplex by the conductive polymer A and / or the conductive polymer B, good white light emission can be obtained by complementing the light emission by the conductive polymer A and the conductive polymer B. . When it is out of the above range, good fluorescence may not be obtained.

The polymer electrolyte contained in the light emitting layer is preferably a polymer having an ethylene oxide skeleton. For example, a resin having an ethylene oxide skeleton represented by the following formula (5) and having a branched structure as a structure having these in the main chain or side chain can be given.
-(C-C-O) _n- (5)
Further, for example, in the ethylene oxide skeleton, the hydrogen atom to be bonded may be substituted with an alkyl group such as methyl or ethyl, or an aryl group having an aromatic ring such as a phenyl group.
Among these, polyalkylene oxide is preferable, and polyethylene oxide is more preferable. This is because it is excellent in terms of workability, ionic conductivity, mechanical properties, and transparency.
The polyethylene oxide preferably has a viscosity average molecular weight (Mv) of 100,000 to 2,000,000, more preferably 300,000 to 900,000. Workability and ionic conductivity become better.

  The content of the polymer electrolyte in the light emitting layer is preferably 10 to 400 parts by weight, more preferably 40 to 160 parts by weight with respect to 100 parts by weight of the total amount of the conductive polymer. When the polymer electrolyte content is less than the lower limit value, the light emitting layer is thin and may be short-circuited easily. When the polymer electrolyte content exceeds the upper limit value, clean surface emission may not be obtained.

Examples of the electrolytic salt contained in the light emitting layer include lithium salts such as LiCl, LiBr, LiI, LiBF ₄ , LiClO ₄ , LiPF ₆ and LiCF ₃ SO ₃ , potassium salts such as KCl, KI, KBr, and KCF ₃ SO ₃ , List sodium salts such as NaCl, NaI, and NaBr, or tetraalkylammonium salts such as tetraethylammonium borofluoride, tetraethylammonium perchlorate, tetrabutylammonium perfluoride, tetrabutylammonium perchlorate, and tetrabutylammonium halide. Can do. The alkyl chain lengths of the quaternary ammonium salts described above may be the same or different, and only one kind may be used as necessary, or two or more kinds may be used in combination. Among these, KCF ₃ SO ₃ is preferable from the viewpoints of ionic conductivity, compatibility, and stability.

  Moreover, an ionic liquid can also be used as an electrolytic salt. The ionic liquid of the present invention means a salt that exists as a liquid at room temperature (25 ° C.). Examples of the cation of the ionic liquid include an imidazolium cation, a pyridinium cation, a pyrrolidinium cation, a piperidinium cation, a tetraalkylammonium cation, a pyrazolium cation, and a tetraalkylphosphonium cation.

  Examples of the imidazolium cation include 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1-allyl-3-methylimidazolium, 1 -Allyl-3-ethylimidazolium, 1-allyl-3-butylimidazolium, 1,3-diallylimidazolium and the like.

  Examples of the pyridinium cation include 1-propylpyridinium, 1-butylpyridinium, 1-ethyl-3- (hydroxymethyl) pyridinium, 1-ethyl-3-methylpyridinium, and the like.

  Examples of the pyrrolidinium cation include N-methyl-N-propylpyrrolidinium, N-methyl-N-butylpyrrolidinium, N-methyl-N-methoxymethylpyrrolidinium, and the like.

  Examples of the piperidinium cation include N-methyl-N-propylpiperidinium.

  Examples of the tetraalkylammonium cation include N, N, N-trimethyl-N-propylammonium and methyltrioctylammonium.

  Examples of the pyrazolium cation include 1-ethyl-2,3,5-trimethylpyrazolium, 1-propyl-2,3,5-trimethylpyrazolium, 1-butyl-2,3,5- And trimethylpyrazolium.

  Examples of the tetraalkylphosphonium cation include tetramethylphosphonium and tetrabutylphosphonium.

In addition, examples of the anion that forms an ionic liquid in combination with the cation include BF ₄ ⁻ , NO ₃ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , CH ₃ CH ₂ OSO ₃ ⁻ , CH ₃ CO ₂ ⁻ , or ^{_{CF 3 CO 2 -, CF 3}} SO 3 -, (CF 3 SO 2) 2 N - [ bis (trifluoromethylsulfonyl) _{imide], (CF 3 SO 2)} 3 C - mentioned fluoroalkyl group-containing anions such as It is done.

  In addition, 0.01-40 weight part is preferable with respect to 100 weight part of total amounts of a conductive polymer, and, as for content of the electrolytic salt in a light emitting layer, More preferably, it is 0.1-20 weight part. If the electrolytic salt content is less than the lower limit value, current may not flow and light may not be emitted. If the content exceeds the upper limit value, doping may proceed excessively, which may cause a short circuit.

  The average layer thickness of the light emitting layer of the present invention is in the range of 1 nm to 1000 nm, more preferably in the range of 10 to 500 nm, and still more preferably in the range of 50 nm to 250 nm. When the average layer thickness is smaller than the lower limit value, a short circuit may occur, and when the upper limit value is exceeded, the efficiency of exciplex formation by the conductive polymer A and / or the conductive polymer B may be reduced. . The light emitting layer of the present invention has the uneven shape described above on at least one surface, and since there are a thin portion and a thick portion, the thin layer and the thick portion are selected equally and the average layer thickness is selected. Ask for.

As for the 1st electrode and 2nd electrode which comprise the light emitting electrochemical element of this invention, at least one electrode is a translucent electrode, ie, a transparent electrode, and it can take out emitted light. Examples of the material for the transparent electrode include tin oxide, zinc oxide, indium oxide, indium tin oxide, indium oxide / zinc oxide compound, tin oxide / antimony compound, and gallium oxide / zinc oxide compound. A preferable transparent electrode is an ITO electrode using indium tin oxide.
The other electrode does not need to be a transparent electrode, for example, aluminum, indium, magnesium, tungsten, titanium, molybdenum, calcium, sodium, potassium, yttrium, lithium, manganese, gold, silver, copper, palladium, platinum Further, metals such as tin, lead, nickel, and alloys of these metals can be used. Of course, it may be a transparent electrode. Aluminum is preferable in terms of conductivity and economy.

In the present invention, the electrode formed by being stacked on the optical substrate is referred to as a first electrode. Therefore, since emitted light is extracted from the optical substrate side, at least the first electrode is a transparent electrode.
The first electrode is formed on an optical substrate by a sputtering method, a vacuum deposition method, or the like using an electrode material such as indium tin oxide.

In the light-emitting electrochemical element of the present invention having the above configuration, the conductive polymer emits light with a specific color by applying a voltage between the first electrode and the second electrode. When two kinds of conductive polymers are used, the conductive polymer A emits blue to blue-green light, and the conductive polymer B emits red to red-orange light to emit white light, or the conductive polymer A is blue. ~ Blue-green light emission, the conductive polymer B emits red to red-orange light, and the exciplex formed by the conductive polymer A or the conductive polymer B emits light with a complementary fluorescent color to the outside. Emitted as white light.
When white light emission is not required, either one of the conductive polymer A or the conductive polymer B may be used as the conductive polymer.

  The light-emitting device of the present invention is configured to include the light-emitting electrochemical element of the present invention and a voltage unit for applying a voltage to the light-emitting electrochemical element. The voltage unit may be either a DC voltage or an AC voltage.

  Next, an example of a method for producing the light-emitting electrochemical element of the present invention will be described with reference to the drawings.

First, a schematic manufacturing procedure of the light-emitting electrochemical element 100 will be described with reference to FIG. The light-emitting electrochemical device 100 has a dispersion solution in which a conductive polymer, an electrolytic salt, and a polymer electrolyte are dissolved and dispersed in a solvent on the surface of an ITO electrode or the like provided as a first electrode 4 on the optical substrate 1 by a vacuum deposition method. For example, it is applied by a spin coat application method, and the light-emitting layer 5 is laminated by removing the solvent by drying. Here, the solvent for the dispersion solution is not particularly limited as long as it dissolves each constituent component. For example, a solvent such as chloroform, cyclohexanone, toluene, and a mixed solvent thereof can be used.
Subsequently, aluminum as the second electrode 6 is laminated on the light emitting layer 5 by vapor deposition and film formation by, for example, a vacuum vapor deposition method.
The light emitting electrochemical device 100 can be manufactured as described above.

  Next, a method for manufacturing the light-emitting electrochemical device 100 will be described in more detail, including a method for forming a concavo-convex shape.

  The optical substrate 1 having a concavo-convex shape can be produced as follows. As shown in FIG. 5, first, while pressing the film-shaped mold 8 on which the concavo-convex pattern is formed on the base material layer 7 formed by applying a sol-gel material as the material of the concavo-convex structure layer 3 on the support substrate 2, The base material layer 7 is cured. Subsequently, the film mold 8 is removed from the base material layer 7 (uneven structure layer 3) after curing. Thereby, the concavo-convex pattern of the film-shaped mold 8 is transferred to the surface of the base material layer 7, and the concavo-convex structure layer 3 having the concavo-convex shape is formed.

  As shown in FIG. 5, the film-shaped mold 8 includes a substrate portion 8a and an uneven portion 8b formed on the substrate portion 8a. Both the substrate portion 8a and the concavo-convex portion 8b have flexibility. A concavo-convex pattern is formed in advance on the surface of the concavo-convex portion 8b by transferring the concavo-convex pattern from a metal mold to be described later. The substrate portion 8a is in the form of a film or a sheet. For example, silicone resin, polyethylene terephthalate (PET), polyethylene terephthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP), polymethyl methacrylate (PMMA), polystyrene (PS), polyimide (PI), or an organic material such as polyarylate. Further, the uneven portion 8b may be integrally formed of the same material as the substrate portion 8a, or a different material may be used. As a material for forming the concavo-convex portion 8b, a photocurable resin, a thermosetting resin, a thermoplastic resin, or the like can be used. Moreover, in order to improve adhesiveness on the board | substrate part 8a (border with 8b), you may surface-treat or provide an easily bonding layer, and prevent invasion of gas, such as a water | moisture content and oxygen. For the purpose, a gas barrier layer may be provided.

The film mold 8 used for transferring the concavo-convex pattern can be manufactured as follows, for example.
In order to produce the film mold 8, first, a mother die having a concavo-convex structure for forming a concavo-convex pattern of the mold is produced. The matrix is, for example, a method using self-assembly (microphase separation) by heating of a block copolymer described in WO2012 / 096368 by the present applicants (hereinafter referred to as “BCP (Block Polymermer) heat” as appropriate. Annealing method) and a method using self-assembly of a block copolymer in a solvent atmosphere disclosed in WO2011 / 007878A1 by the present applicants (hereinafter referred to as “BCP solvent annealing method” as appropriate). It may be formed. Further, the matrix may be formed by a photolithography method instead of the BCP thermal annealing method and the BCP solvent annealing method. In addition, for example, a mother die is also produced by a fine machining method such as a cutting method, a direct electron beam drawing method, a particle beam beam machining method, and an operation probe machining method, and a fine machining method using self-organization of fine particles. be able to. In the case of forming the mother die by the BCP thermal annealing method, any material can be used as a material for forming the mother die. For example, a block copolymer composed of two combinations selected from the group consisting of styrene-based polymers such as polystyrene, polyalkyl methacrylates such as polymethyl methacrylate, polyethylene oxide, polybutadiene, polyisoprene, polyvinyl pyridine, and polylactic acid. It may be a coalescence.

  The BCP solvent annealing method is the same as the BCP thermal annealing method described in WO2012 / 096368, but instead of performing the first heating step, the etching step, and the second heating step, In this method, the thin film is subjected to solvent annealing (solvent phase separation) in an atmosphere of an organic solvent vapor to form a phase separation structure of the block copolymer in the thin film. By this solvent annealing treatment, self-assembly of the block copolymer proceeds, and the block copolymer can be microphase-separated to form a matrix having an uneven structure.

  The solvent annealing treatment can be performed, for example, by providing a vapor atmosphere of an organic solvent inside a sealable container such as a desiccator, and exposing the target block copolymer thin film to this atmosphere. The organic solvent vapor may be at a high concentration to promote phase separation of the block copolymer. The organic solvent vapor may be a saturated vapor pressure. In this case, the concentration management is relatively easy. For example, when the organic solvent is chloroform, the saturated vapor amount is known to be 0.4 g / L to 2.5 g / L at room temperature (0 ° C. to 45 ° C.). The treatment time of the solvent annealing treatment may be 6 hours to 168 hours, or may be 12 hours to 48 hours, or 12 hours to 36 hours.

  The organic solvent used for the solvent annealing treatment may be an organic solvent having a boiling point of 20 ° C to 120 ° C. For example, chloroform, dichloromethane, toluene, tetrahydrofuran (THF), acetone, carbon disulfide, a mixed solvent thereof or the like can be used. Of these, chloroform, dichloromethane, acetone, acetone / carbon disulfide mixed solvent may be used. The ambient temperature of the solvent annealing may be performed within a range of 0 ° C to 45 ° C. If the ambient temperature of the solvent annealing is higher than 45 ° C., the concavo-convex structure to be formed cannot maintain its shape and it becomes difficult to obtain a desired concavo-convex structure. In an environment lower than 0 ° C., the organic solvent is difficult to evaporate, and phase separation of the block copolymer is difficult to occur.

After the solvent annealing treatment, heat treatment may be further performed. Since the concavo-convex structure has already been formed by the solvent annealing treatment, this heat treatment smooths the formed concavo-convex structure, but it is not always necessary. For some reason, there are cases where protrusions are formed on a part of the surface of the concavo-convex structure after the solvent annealing treatment, or for the purpose of adjusting the period and height of the concavo-convex structure. The heating temperature can be, for example, not less than the glass transition temperature of the polymer segment constituting the block copolymer, for example, not less than the glass transition temperature of those homopolymers and not more than 70 ° C. higher than the glass transition temperature. be able to. The heat treatment can be performed in an air atmosphere using an oven or the like. After the solvent annealing treatment, the etching may be performed by etching using energy rays such as UV or excimer UV, or by a dry etching method such as RIE (reactive ion etching). Further, heat treatment may be performed.
As described above, a matrix having an uneven structure can be manufactured.

Next, based on the mother die, a metal mold to which the concave and convex structure of the mother die is transferred is produced. An example for metal mold fabrication is shown below.
First, a seed layer serving as a conductive layer for electroforming is formed on the concavo-convex structure layer of the matrix by electroless plating, sputtering, vapor deposition, or the like. The thickness of the seed layer may be 10 nm or more in order to make the current density in the subsequent electroforming process uniform and make the thickness of the metal layer deposited by the subsequent electroforming process constant. Examples of seed layer materials include nickel, copper, gold, silver, platinum, titanium, cobalt, tin, zinc, chromium, gold / cobalt alloy, gold / nickel alloy, boron / nickel alloy, solder, copper / nickel / chromium An alloy, a tin-nickel alloy, a nickel-palladium alloy, a nickel-cobalt-phosphorus alloy, and an alloy thereof can be used. Next, a metal layer is deposited on the seed layer by electroforming (electroplating) to produce a metal mold. As a material for the metal layer deposited by electroforming, any of the above metal species that can be used as a seed layer can be used. The produced metal mold preferably has an appropriate hardness and thickness in view of the ease of processing such as pressing, peeling and cleaning to the subsequent film mold 8. The thickness is preferably 10 to 3000 μm.

  The produced metal mold is peeled from the matrix. The metal mold may be peeled physically or may be removed by dissolving the matrix using an organic solvent that dissolves the matrix, such as toluene, tetrahydrofuran (THF), chloroform, or the like. When the metal mold is peeled from the mother die, the remaining material components can be removed by washing. As a cleaning method, wet cleaning using a surfactant or the like, or dry cleaning using ultraviolet rays, plasma, or the like can be used. Further, for example, the remaining material components may be adhered and removed using an adhesive or an adhesive.

  As described above, the concave / convex pattern formed on the metal mold produced as described above has a matrix concave / convex structure formed by microphase separation of the block copolymer by the BCP thermal annealing method or the BCP solvent annealing method. It is the transferred concavo-convex pattern.

Using this metal mold, the film-shaped mold 8 is produced as follows.
A curable resin is applied to the substrate portion 8a to form a resin layer (a portion that becomes the uneven portion 8b) on the substrate portion 8a, and then the resin layer is cured while pressing the uneven portion of the metal mold against the resin layer. Here, as the curable resin, for example, epoxy, acrylic, methacrylic, vinyl ether, oxetane, urethane, melamine, urea, polyester, phenol, cross-linked liquid crystal, fluorine, silicone Various resins such as a system can be used. Examples of the method for applying the curable resin to the substrate portion 8a include spin coating, spray coating, dip coating, dropping, gravure printing, screen printing, letterpress printing, die coating, curtain coating, Various coating methods such as an inkjet method and a sputtering method can be employed. Furthermore, the conditions for curing the curable resin vary depending on the type of resin used. For example, the curing temperature is in the range of room temperature to 250 ° C., and the curing time is in the range of 0.5 minutes to 3 hours. There may be. It is also possible by a method of curing by irradiation of energy rays such as ultraviolet rays or electron beams, in which case the dose may be in the range of ^{20mJ / cm 2 ~5J / cm 2} .

  Next, the metal mold is removed from the cured resin layer. The method for removing the metal mold is not limited to the mechanical peeling method, and a known method can be adopted. In this way, the film mold 8 having the concavo-convex portion 8b in which the concavo-convex pattern is formed on the substrate portion 8a is produced. This film mold 8 can also be used as an optical substrate in the form of a film.

  The dimensions, particularly the length, of the film mold 8 can be appropriately set according to the dimensions of the optical substrate 1 to be mass-produced and the number (lot number) of the optical substrates 1 that are continuously manufactured in one manufacturing process. For example, a long mold having a length of 10 m or more may be used, and the film-shaped mold 8 wound around the roll may be continuously transferred to a plurality of substrates while being continuously fed from the roll. The film mold 8 may have a width of 50 to 3000 mm and a thickness of 1 to 500 μm. Surface treatment or easy adhesion treatment may be performed between the substrate portion 8a and the concavo-convex portion 8b in order to improve adhesion. Moreover, you may perform a mold release process on the uneven | corrugated pattern surface of the uneven | corrugated | grooved part 8b as needed.

The concavo-convex pattern of the film mold 8 produced as described above is transferred to the base material layer 7 to be the concavo-convex structure layer 3 of the optical substrate 1 as follows.
As shown in FIG. 5, when the film-shaped mold 8 is fed between the pressing roll 9 and the support substrate 2 conveyed immediately below, the uneven pattern of the uneven portions 8 b of the film-shaped mold 8 is changed to the support substrate 2. Transferred to the upper base material layer 7. Here, after pressing the film-shaped mold 8 against the base material layer 7, the base material layer 7 may be temporarily fired. By pre-firing, the gelation of the base material layer 7 proceeds, the uneven pattern is solidified, and is less likely to collapse during peeling. When performing pre-baking, you may heat at the temperature of 40-150 degreeC in air | atmosphere. Note that the preliminary firing is not necessarily performed.

  After the pressing of the film mold 8 or the preliminary firing of the base material layer 7, the film mold 8 is peeled from the base material layer 7. A known peeling method can be employed for peeling the film mold 8. For example, the film mold 8 may be peeled off while heating. As a result, the gas generated from the base material layer 7 can escape and bubbles can be prevented from being generated in the base material layer 7. When the roll process is used, the peel force may be smaller than that of the plate-type mold used in the press method, and the base material layer 7 does not remain on the film-type mold 8, and the film-type mold 8 can be easily attached to the base material layer 7. Can be peeled off. In particular, since the base material layer 7 is pressed while being heated, the reaction is likely to proceed, and the film mold 8 is easily peeled off from the base material layer 7 immediately after pressing. Further, in order to improve the peelability of the film mold 8, a peeling roll 10 may be used. In this embodiment, as shown in FIG. 5, the peeling roll 10 is provided on the downstream side of the pressing roll 9, and the film-shaped mold 8 is rotated and supported while being biased by the peeling roll 10 against the base material layer 7. Thereby, the state in which the film-shaped mold 8 is attached to the base material layer 7 can be maintained only for the distance between the pressing roll 9 and the peeling roll 10 (a certain time). Then, the course of the film mold 8 is changed so that the film mold 8 is pulled up above the peeling roll 10 on the downstream side of the peeling roll 10. Thereby, the film-shaped mold 8 is peeled off from the base material layer 7 in which the unevenness is formed. In addition, during the period in which the film-shaped mold 8 is attached to the base material layer 7, the above-described base material layer 7 may be temporarily fired or heated. In addition, when using the peeling roll 10, peeling of the film-shaped mold 8 can be made still easier by peeling, for example, heating at 40-150 degreeC.

  After peeling off the film-shaped mold 8 from the base material layer 7, the base material layer 7 may be cured. Thereby, the concavo-convex structure layer 3 having the concavo-convex shape as shown in FIG. 1 is formed. In the present embodiment, the base material layer 7 made of a sol-gel material can be cured by the main baking. By the main baking, the hydroxyl group contained in the silica (amorphous silica) constituting the base material layer 7 is detached, and the base material layer 7 becomes stronger. The main baking is preferably performed at a temperature of 200 to 1200 ° C. for about 5 minutes to 6 hours. Thus, the base material layer 7 is cured, and the concavo-convex structure layer 3 having a concavo-convex shape corresponding to the concavo-convex pattern of the film mold 8 is formed. At this time, when the concavo-convex structure layer 3 is made of silica, it is in an amorphous state, a crystalline state, or a mixed state of amorphous and crystalline depending on the firing temperature and firing time.

  Further, when the uneven pattern of the uneven portion 8b of the film mold 8 is transferred to the underlying material layer 7 on the support substrate 2, the underlying material layer 7 is photocured by irradiating it with an energy beam such as UV or excimer UV. Thus, the optical substrate 1 may be manufactured. Further, a gas barrier layer may be provided on the surface of the concavo-convex structure layer 3 for the purpose of preventing the entry of gas such as moisture and oxygen.

The first electrode 4 such as an ITO electrode is stacked on the optical substrate 1 having the concavo-convex shape produced as described above by a vacuum deposition method or the like. By laminating the first electrode 4 in this manner, a concavo-convex pattern reflecting the concavo-convex shape of the optical substrate 1 is also formed on the surface of the first electrode 4 as shown in FIG. Subsequently, a light emitting layer material solution containing a conductive polymer, an electrolytic salt and a polymer electrolyte is applied onto the first electrode 4 by a coating method such as spin coating or dip coating, and then the solvent is dried. The light emitting layer 5 is formed by laminating. By laminating the light emitting layer 5 in this manner, an uneven pattern reflecting the uneven shape of the optical substrate 1 is also formed on the surface of the light emitting layer 5 (FIG. 3). In this case, since the light emitting layer is formed by a coating method, the uneven shape of the light emitting layer becomes an uneven shape in which the unevenness is less than the uneven shape of the first electrode 4, but the uneven shape of the optical substrate 1 is adjusted. Thereby, the uneven | corrugated shape which has desired light extraction performance can be formed. Further, as long as the unevenness shape with a sufficient depth is maintained on the surface in contact with the first electrode 4, the unevenness on the surface opposite to the surface in contact with the first electrode 4 may be relaxed, and the substantially flat surface It may be. In order to improve the light extraction performance, it is preferable that the light emitting layer 5 has an uneven surface on both sides. Further, a second electrode 6 made of aluminum or the like is laminated on the light emitting layer 5 by a vacuum vapor deposition method or the like.
The surface of the second electrode 6 opposite to the light emitting layer 5 may have an uneven shape corresponding to the uneven shape of the light emitting layer 5 or the like as shown in FIG.

  Like the manufacturing method described above, the light emitting electrochemical device 100 is manufactured by the method of forming the uneven shape on the first electrode 4 and the light emitting layer 5 so as to reflect the uneven shape of the optical substrate 1. It is preferable at the point which can improve the ease and light extraction performance.

  The device characteristics of the light-emitting electrochemical device 100 of the present invention can be evaluated by the luminance of the emitted light. Further, when white light is emitted using two types of conductive polymers, the degree of whiteness can be evaluated by the numerical value of the xy coordinates of the chromaticity diagram (chromaticity coordinates).

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
In this example, an optical substrate having a concavo-convex structure layer was produced as an optical substrate, and a light-emitting electrochemical element was manufactured by a method of laminating a first electrode, a light-emitting layer, and a second electrode on the structure layer.

<Compound of each layer constituting light emitting electrochemical element>
[Optical substrate 1]
Support substrate 2: non-alkali glass [OA10GF, manufactured by Nippon Electric Glass Co., Ltd.]
Base material layer 7 for the uneven structure layer 3; Sol-gel material containing tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES) [first electrode 4]; ITO (indium tin oxide) electrode [light emitting layer 5 ]
Conductive polymer A (A); poly (9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) of formula (1d) (manufactured by Aldrich). LUMO: -3.2 eV, HOMO: -6.1 eV
Conductive polymer B (B): poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylene vinylene] (MEH-PPV) (made by Aldrich) of the above formula (2). LUMO: -3.4 eV, HOMO: -5.5 eV
・ Polymer electrolyte (C); polyethylene oxide (PEO) (Mv 600,000, manufactured by Aldrich)
Electrolytic salt (D); KCF ₃ SO ₃ (Aldrich)
The energy level of each conductive polymer was determined by the following method.
The HOMO level of the conductive polymer is determined by determining the oxidation potential E (ferrocene standard) from the rising edge of the oxidation wave of the cyclic boil tomogram (CV), then setting the ferrocene standard work function to 5.23 eV, and the formula: HOMO = -(EE + 5.23). Here, “e” is a unit charge. The band gap energy (Eg) was determined from the rise of the absorption peak in the UV-visible spectrum. The LUMO level is calculated from the formula LUMO = HOMO + Eg.
[Second electrode 6]; Aluminum

<Configuration of Light-Emitting Layer 5>
The composition of the above compounds in the light emitting layer 5 in Examples 1 and 2 and Comparative Examples 1 and 2 and the blending ratio thereof are shown in Table 1 (Compositions 1 and 2). Table 1 also shows the LUMO difference (absolute value) of both polymers in Example 2 using both the conductive polymers A and B.

Example 1
1. Film Mold 8; Production of Mold M1 Mold M1 as film mold 8 for producing optical substrate 1 was produced as follows.
(1) Fabrication of matrix (BCP solvent annealing method)
A matrix having a concavo-convex structure for forming the concavo-convex pattern of the mold M1 was prepared by a mixture of a block copolymer of styrene and methyl methacrylate and polyethylene glycol. As the copolymer, a block copolymer having the following properties manufactured by Polymer Source was used.
Block copolymer: number average molecular weight (Mn): 1,700,000, Mn of polystyrene part (PS segment); 900,000, Mn of polymethyl methacrylate part (PMMA segment); 800,000, PS segment: PMMA segment (volume ratio) = 55: 45, molecular weight distribution (Mw / Mn) = 1.26, PS segment glass transition point (Tg) = 107 ° C., PMMA segment Tg = 134 ° C.

“PS segment: PMMA segment” in the block copolymer was calculated assuming that the density of polystyrene (PS) was 1.05 g / cm ³ and the density of polymethyl methacrylate (PMMA) was 1.19 g / cm ³ .
Mn and Mw (weight average molecular weight) of the block copolymer and each segment are connected in series to gel permeation chromatography (manufactured by Tosoh Corporation, model number “GPC-8020”, TSK-GEL SuperH1000, SuperH2000, SuperH3000, and SuperH4000. Measured).
Tg of each segment was measured using a differential scanning calorimeter (manufactured by Perkin-Elmer, product name “DSC7”) while increasing the temperature at a temperature increase rate of 20 ° C./min in the temperature range of 0 to 200 ° C. did.
The solubility parameters of PS and PMMA are 9.0 and 9.3, respectively (refer to Chemical Handbook Application Edition 2nd revised edition).

  210 mg of this block copolymer and 52.5 mg of polyethylene glycol 2050 (Mn = 2050, manufactured by Aldrich) were dissolved in toluene to prepare 15 g of a block copolymer-polyethylene glycol mixed solution. Subsequently, the mixed solution was filtered through a membrane filter having a pore size of 0.5 μm. Hereinafter, the mixed solution after filtration is referred to as a purified mixed solution.

1 g of silane coupling agent KBM-5103 manufactured by Shin-Etsu Silicone Co., Ltd., 1 g of ion exchange water, 0.1 mL of acetic acid, 19 g of isopropyl alcohol, and a mixed solution in which the above components were mixed were applied onto a glass substrate by spin coating. (After 10 seconds at a rotational speed of 500 rpm, it was subsequently performed at 800 rpm for 45 seconds). A heat treatment was performed at 130 ° C. for 15 minutes to obtain a silane coupling-treated glass substrate (hereinafter simply referred to as a treated substrate).
The purified mixed solution was applied onto the treated substrate by spin coating and dried at room temperature in the atmosphere to form a thin film having a thickness of 100 to 120 nm. The spin coating was performed at a rotational speed of 200 rpm for 10 seconds, and subsequently at 300 rpm for 30 seconds.

  Next, the processing substrate on which the thin film was formed was left in a desiccator previously filled with chloroform vapor for 35 hours at room temperature to perform a solvent annealing treatment. A screw bottle filled with 100 g of chloroform was installed in the desiccator (capacity 5 L), and the atmosphere in the desiccator was filled with chloroform having a saturated vapor pressure.

Unevenness was observed on the surface of the thin film after the solvent annealing treatment, and it was found that the block copolymer constituting the thin film was micro-layer separated. When the cross section of this thin film was observed with a transmission electron microscope (TEM) (H-7100FA manufactured by Hitachi, Ltd.), the circular cross section of the PS portion was separated from each other in the direction parallel to the substrate surface, and the direction perpendicular to the substrate surface ( When arranged together with the analysis image of the atomic force microscope, it was found that the PS portion was phase-separated from the PMMA portion into a horizontal cylinder structure. The PS part was a core (island), and the PMMA part was surrounded by it (the sea).
As described above, a matrix having an uneven shape was produced.

(2) Production of Metal Mold A 20 nm nickel layer was formed as a current seed layer on the irregular surface of the mother die produced above by sputtering. Next, the mother mold on which the nickel layer was formed was placed in a nickel sulfamate bath, and electrocasting (maximum current density 0.05 A / cm ² ) was performed at a temperature of 50 ° C. to deposit nickel until the thickness reached 250 μm. The mother die was mechanically peeled from the nickel electroformed body thus obtained. Next, the nickel electroformed body was immersed in a tetrahydrofuran solvent for 2 hours for primary cleaning.
Subsequently, the nickel electroformed body was taken out and dried. After the acrylic UV curable resin was applied to the surface of the nickel electroformed body in contact with the mother die and cured, the cured resin was peeled off. By repeating the application, curing, and peeling of the acrylic UV curable resin three times, the polymer deposits from the matrix that had adhered to the surface of the nickel electroformed body were almost completely removed.
Next, the nickel electroformed body was immersed in Chemisole 2303 manufactured by Nippon CB Chemical Co., Ltd., and further washed with stirring at 50 ° C. for 2 hours, and then subjected to UV ozone treatment for 10 minutes.

Next, the nickel electroformed body was immersed in a fluorine-based mold release agent “OPTOOL HD-2101TH” (manufactured by Daikin Chemicals Sales Co., Ltd.) for about 1 minute, dried, and then allowed to stand overnight. After standing, the nickel electroformed body was immersed in “HDTH” (manufactured by Daikin Chemicals Sales Co., Ltd.) and subjected to ultrasonic treatment rinsing for about 1 minute.
As described above, a nickel metal mold (hereinafter referred to as a nickel mold) having an uneven shape was produced.

(3) Production of mold M1 After applying a fluorine-based UV curable resin on a PET substrate (substrate part 8a) [Cosmo Shine A-4100, manufactured by Toyobo Co., Ltd.], ultraviolet rays were applied at 600 mJ / cm while pressing the nickel mold. ^The fluorine-based UV curable resin was cured by irradiating with ² (uneven portion 8b). After the resin was cured, the nickel mold was peeled from the cured resin.
As described above, a mold M1 (film mold 8) composed of the concavo-convex portion 8b onto which the concavo-convex shape of the nickel mold surface was transferred and the substrate portion 8a was obtained.

2. Preparation of optical substrate 1 and analysis of concavo-convex structure layer 3 (1) Preparation of optical substrate 1 Tetraethoxysilane (TEOS) 3.74 g was mixed with a solution in which 24.3 g of ethanol, 2.15 g of water and 0.0098 g of concentrated hydrochloric acid were mixed. And methyltriethoxysilane (MTES) 0.89 g was added dropwise and stirred at 23 ° C. and humidity 45% for 2 hours to obtain a sol-gel material solution of SiO ₂ .
The sol-gel material solution is bar-coated on a 10 cm × 10 cm × 0.07 cm non-alkali glass support substrate 2 (OA10GF, manufactured by Nippon Electric Glass Co., Ltd.) to form a 40 μm-thick coating film (underlying material layer 7). Formed. A doctor blade (manufactured by YOSHIMITSU SEIKI) was used as a bar coater. The doctor blade was designed to have a film thickness of 5 μm, but an imide tape with a thickness of 35 μm was attached to the doctor blade so that the film thickness of the film was 40 μm.
After forming the base material layer 7, as shown in FIG. 5, the mold M <b> 1 was pressed against the base material layer 7 using a pressing roll 9 heated to 80 ° C., and the uneven pattern of the mold M <b> 1 was transferred to the base material layer 7. . The underlying material layer 7 to which the concavo-convex pattern was transferred was baked at 300 ° C. for 60 minutes to form the concavo-convex structure layer 3 on the support substrate 2. The press roll 9 is a roll having a heater inside and covered with heat-resistant silicone having an outer periphery of 4 mm thick, and has a roll diameter φ of 50 mm and an axial length of 350 mm.
The optical substrate 1 was produced as described above.

(2) Concavity and convexity analysis of concave-convex structure layer 3 of optical substrate 1 The concave-convex shape of concave-convex structure layer 3 is measured by an atomic force microscope (scanning probe microscope “Nonavi II station / E-sweep” with an environmental control unit manufactured by SII Nanotechnology). ) To obtain an unevenness analysis image. The unevenness analysis image is shown in FIG. 6 at different magnifications (a) and (b).
The analysis conditions of the atomic force microscope are as follows.
Measurement mode: Dynamic force mode Cantilever: SI-DF40 (material: Si, lever width: 40 μm, tip diameter: 10 nm) Measurement atmosphere: in air Measurement temperature: 25 ° C.

<Average value of uneven depth distribution>
An arbitrary 3 μm square (3 μm length, 3 μm width) measurement region of the concavo-convex structure layer 3 was measured to obtain a concavo-convex analysis image. The total number (N) of the measurement points of the unevenness depth in the measurement region was 65536 points (256 vertical points × 256 horizontal points; measurement at a resolution of 256 × 256 pixels). The average value (m) of the uneven depth distribution was determined by the formula (I) using the measured uneven depth value. In this example, the unit of m and x _i in formula (I) is (nm).
[In formula (I), m indicates the average value of uneven depth distribution, the total number of N measuring points, the irregularity depth of the x _i is the i-th measurement point. ]
The value of m of the concavo-convex structure layer 3 of Example 1 was 79 nm.

<Standard deviation of uneven depth>
The standard deviation (σ) of the unevenness depth was determined by the following formula (II).

Wherein (II), sigma represents a standard deviation of the unevenness depth, the average value of m is uneven depth distribution, N is the total number of measurement points, the irregularity depth of the x _i is the i-th measurement point. ]
The value of σ of the uneven structure layer 3 of Example 1 was 47 nm.

<Average depth of irregularities>
A measurement area of 3 μm square (3 μm in length and 3 μm in width) at an arbitrary position of the concavo-convex structure layer 3 was measured to obtain a concavo-convex analysis image. In such an unevenness analysis image, the distances in the depth direction of the bottoms of arbitrary adjacent recesses and the tops of the protrusions are measured at 100 points, and the average is calculated as the average depth of the unevenness. In the analysis image obtained in this example, the average depth of the unevenness of the uneven structure layer 3 was 138 nm.

<Average pitch of unevenness>
A measurement area of 3 μm square (3 μm in length and 3 μm in width) at an arbitrary position of the concavo-convex structure layer 3 was measured to obtain a concavo-convex analysis image. In this unevenness analysis image, the distance between the tops of any adjacent convex portions or the bottom portions of adjacent concave portions was measured at 100 points, and the average was calculated as the average pitch of the unevenness. In the analysis image obtained in this example, the average pitch of the unevenness of the uneven structure layer was 770 nm.

<Fourier transform image of unevenness analysis image>
The obtained unevenness analysis image was subjected to flat processing including primary inclination correction, and then subjected to two-dimensional fast Fourier transform processing to obtain a Fourier transform image. The Fourier transform image is shown in the upper left of (a) and (b) of FIG.
As shown in FIG. 6, the Fourier transform image obtained in this way shows a circular pattern whose center is the origin whose absolute value of the wave number is 0 μm ⁻¹ , and the circular pattern described above. Has been confirmed to be present in a region where the absolute value of the wave number is in the range of 10 μm ⁻¹ or less.

3. Light-emitting electrochemical element 100; Preparation of element (1) and analysis of light-emitting layer 5 (1) Preparation of element (1) Next, ITO is sputtered on the optical substrate 1 provided with the uneven structure layer 3 obtained above. The film was formed with an average thickness of 120 nm by the method. As a result, an uneven shape reflecting the uneven pattern of the uneven structure layer 3 was formed on the surface of the first electrode 4. Subsequently, on the first electrode 4, each component of the composition 1 shown in Table 1 was dissolved in a mixed solvent of chloroform / cyclohexanone (1.62: 1.0) to obtain a solution concentration of 9.5 mg / mL (in 1 mL of the solution). The composition 1 solution in which the composition 1 was 9.5 mg) was prepared. After the composition 1 solution was applied by spin coating, the mixed solvent was removed by drying, and the light emitting layer 5 having an average thickness of 100 nm was laminated. Furthermore, the second electrode 6 having an average thickness of 100 nm was laminated on the light emitting layer 5 by vacuum deposition of aluminum.
Through the above operation, an element (1) in which all of the first electrode 4, the light emitting layer 5, and the second electrode 6 have a concavo-convex shape reflecting the concavo-convex pattern of the concavo-convex structure layer 3 of the optical substrate 1a was produced.

(2) Analysis of the uneven shape of the light emitting layer 5 of the element (1) As in the case of the optical substrate 1, the uneven shape of the light emitting layer 5 analyzed by AFM is shown in FIG. 7 with different magnifications (a) and (b). It shows with. Table 2 shows the analysis results of the average value of the unevenness distribution, the standard deviation of the unevenness depth, the average depth of the unevenness, and the average pitch of the unevenness. The uneven shape of the light emitting layer 5 was measured before the second electrode 6 was laminated.
As can be seen from Table 2, the value of each numerical value specifying the unevenness of the concavo-convex shape of the light emitting layer 5 was smaller than the value of each numerical value specifying the unevenness of the concavo-convex shape of the uneven structure layer 3.
Moreover, the Fourier transform image of the light emitting layer 5 is shown together with the upper left of (a) and (b) of FIG. The obtained Fourier transform image shows a circular pattern whose center is the origin where the absolute value of the wave number is 0 μm ⁻¹ , and the circular pattern has an absolute value of the wave number of 10 μm ⁻¹ or less. It was confirmed that it exists in the area within the range.

4). Measurement of Luminous Performance of Element (1) Regarding the luminous performance of element (1), emitted light obtained from the luminance of emitted light when voltage is applied and the ratio of the luminance to the luminance of element (3) of Comparative Example 1 described later. The efficiency improvement rate and the chromaticity diagram were evaluated. Table 3 shows the measurement results. In Example 1, red-orange light emission was obtained.
The efficiency improvement rate was the following criterion.
A: Brightness of 1.5 times or more of the brightness of the element (3) of Comparative Example 1 B: Brightness of 1.3 times or more and less than 1.5 times of the brightness of the element (3) of Comparative Example 1 C: Comparative Example The luminance of the element (3) of 1.0 or more and less than 1.3 times the luminance of the element (3) The change in current efficiency of the element (1) over time is compared with the element (3) of Comparative Example 1 below. As shown in FIG. Here, the current efficiency is expressed in luminous intensity per unit current.

(Example 2)
The light-emitting electrochemical element 100 is the same as the light-emitting electrochemical element 100 except that the composition of the light-emitting layer 5 is changed from the composition 1 of Example 1 to the composition 2 of Table 1 and the mold M1 is used. (2) was produced. Moreover, the uneven | corrugated shape of the uneven structure layer 3 of the element (2) and the light emitting layer 5 was analyzed similarly to Example 1, and the light emission performance of the element (2) was measured. The efficiency improvement rate was determined by comparison with the luminance of the element (4) of Comparative Example 2. The results are shown in Tables 2 and 3.

(Comparative Example 1)
1. Light-emitting electrochemical element 100 ′; Production of element (3) and measurement of light-emitting performance No uneven shape is formed on the optical substrate 1, that is, no production of the uneven structure layer 3 using the film-shaped mold 8 is carried out (optical substrate) The first electrode 4 ′, the light emitting layer 5 ′ and the second electrode 6 ′ are laminated in the same manner as in Example 1 except that 1 ′ is the support substrate 2 only), and all the layers as shown in FIG. A device (3) that is flat without having a thickness was produced. The light emitting performance of the element (3) was measured in the same manner as in Example 1. The results are shown in Tables 2 and 3.

(Comparative Example 2)
1. Production of light emitting electrochemical element 100 ′; production of element (4) and measurement of light emission performance No irregularity is formed on optical substrate 1, that is, production of irregular structure layer 3 using film mold 8 is not carried out (optical substrate) The first electrode 4 ′, the light emitting layer 5 ′, and the second electrode 6 ′ are stacked in the same manner as in Example 2 except that 1 ′ is the support substrate 2 only), and all the layers as shown in FIG. A device (4) which is flat without having a thickness was produced. The light emitting performance of the element (4) was measured in the same manner as in Example 1. The results are shown in Tables 2 and 3.

  As is clear from the results in Table 3, Examples 1 and 2 exhibited about 1.5 times the luminance in comparison with Comparative Examples 1 and 2, respectively. It can also be seen that Example 2 emits white light. Therefore, it can be seen that the light-emitting electrochemical element in which the surface of the light-emitting layer of the present invention has a specific concavo-convex shape exhibits excellent light-emitting characteristics as compared with a light-emitting electrochemical element in which the light-emitting layer does not have a concavo-convex shape.

DESCRIPTION OF SYMBOLS 1, 1 'Optical substrate 2 Supporting substrate layer 3 Uneven structure layer 4, 4' 1st electrode 5, 5 'Light emitting layer 6, 6' 2nd electrode 7 Base material layer 8 Film-shaped mold 8a Substrate part 8b Uneven part 9 Press Roll 10 Peeling roll 100, 100 'Light emitting electrochemical element

Claims (17)

In a light-emitting electrochemical element having a laminated structure in the order of an optical substrate, a first electrode, a light-emitting layer, and a second electrode,
The light emitting layer contains a conductive polymer, a polymer electrolyte and an electrolytic salt,
At least one surface of the light emitting layer has an uneven shape,
Luminescent electrochemical element. When a voltage is applied between the first electrode and the second electrode, the conductive polymer emits light.
The light-emitting electrochemical device according to claim 1. The conductive polymer is composed of at least a conductive polymer A and a conductive polymer B,
The absolute value of the energy difference between the highest occupied orbit (HOMO) or the lowest unoccupied orbit (LUMO) between the conductive polymer A and the conductive polymer B is 0.5 eV or less.
The light-emitting electrochemical device according to claim 1. When a voltage is applied between the first electrode and the second electrode, the conductive polymer A emits blue to blue green light, and the conductive polymer B emits red to red orange light to emit white light. To
The light-emitting electrochemical device according to claim 3. The optical substrate is a laminate of a support substrate layer and an uneven structure layer,
The concavo-convex structure layer has a concavo-convex shape on a surface not in contact with the support substrate layer,
The light-emitting electrochemical element according to any one of claims 1 to 4. The extending direction of the convex and concave portions of the light emitting layer is irregularly distributed in plan view,
The light-emitting electrochemical element according to any one of claims 1 to 5. When a voltage is applied between the first electrode and the second electrode, an exciplex is formed by the conductive polymer A and / or the conductive polymer B, and fluorescence is emitted from the exciplex. ,
The light-emitting electrochemical element according to any one of claims 3 to 6. The exciplex is an excimer formed between the conductive polymers A or the conductive polymers B, or an exciplex or an electroplex formed between the conductive polymer A and the conductive polymer B. , Emitting excimer fluorescence, exciplex fluorescence or electroplex fluorescence, respectively,
The light-emitting electrochemical element according to claim 7. The conductive polymer A is a conductive polymer having a fluorene skeleton.
The light-emitting electrochemical element according to any one of claims 3 to 8. The conductive polymer having a fluorene skeleton is a compound represented by the formula (1).
The light-emitting electrochemical device according to claim 9.
[In Formula (1), R is a C1-C20 alkyl group, m shows a polymerization degree and represents the integer of 5 or more. ] The conductive polymer B is at least one conductive polymer selected from a conductive polymer having a phenylene vinylene skeleton and a conductive polymer having a thiophene skeleton.
The light-emitting electrochemical element according to any one of claims 3 to 10. The conductive polymer having a phenylene vinylene skeleton is a compound represented by formula (2) or (3), and the conductive polymer having a thiophene skeleton is a compound represented by formula (4).
The light-emitting electrochemical device according to claim 11.
[In Formula (2), W shows a polymerization degree and represents an integer greater than or equal to 5. ]
[In Formula (3), X represents a polymerization degree and represents an integer of 5 or more. ]
[In Formula (4), Y and Z show the degree of polymerization, each independently represents an integer of 5 or more, and may be the same or different. ] The polymer electrolyte is polyethylene oxide.
The light-emitting electrochemical element according to any one of claims 1 to 12. The conductive polymer A is poly (9,9-di-n-dodecylfluorenyl-2,7-diyl).
The light-emitting electrochemical element according to any one of claims 3 to 13. The conductive polymer B is poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylenevinylene], poly [2-methoxy-5- (3 ′, 7′-dimethyloctyloxy) 1,4-phenylene vinylene], poly [octyl-thiophene], poly [decyloxy-thiophene], and at least one conductive polymer selected from a copolymer of octyl-thiophene and desiloxy-thiophene,
The light-emitting electrochemical element according to any one of claims 3 to 14. The average pitch of the concavo-convex shape of the light emitting layer is 100 to 1500 nm, and the standard deviation of the concavo-convex depth of the concavo-convex structure layer is 10 to 100 nm.
The light-emitting electrochemical element according to any one of claims 1 to 15. The light-emitting electrochemical element according to any one of claims 1 to 16, and a voltage unit for applying a voltage between the first electrode and the second electrode of the light-emitting electrochemical element,
Light emitting device.