JP2002056980A - Organic el layer coating fluid, organic el element and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL element (a pixel) and an organic EL display enabled to display in monochrome and in color. SOLUTION: The organic EL layer coating fluid to be used for the formation of the organic EL element, contains a leveling agent and a luminous material or an electric charge transport material, and the added volume of the leveling agent (L) fulfills the relation expressed so that the viscosity of L (cp) × the volume of the leveling agent L added to the luminous material or the electric charge transport material in (wt.%)<200.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic EL device (pixel) capable of monochrome and full-color display and an organic EL device.
The present invention relates to a coating liquid for forming an organic EL layer for manufacturing an L display, an organic EL element and an organic EL display using the same, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, demands for thin, low-power-consumption, lightweight display elements have been increasing with the advancement of information, and low-voltage driven, high-brightness organic EL displays have attracted attention. In particular, recent research and development has significantly improved the luminous efficiency of organic EL devices using organic (polymer) materials.
Practical application to organic EL displays has begun.

[0003] In manufacturing an organic EL display, a polymer material can be formed into a film by a wet process by coating, so that cost reduction is expected.
One of the important research objectives is a patterning method of a light emitting layer for colorization, and an ink jet method (Japanese Patent Application Laid-Open No. 10-12377 and ICPA'99, p16
0), and patterning of the light emitting layer by a printing method (JP-A-3-269995 and JP-A-11-273859).

[0004]

However, in an organic EL display manufactured by an ink-jet method or a printing method, it is difficult to form a film having a smooth surface. There has been a problem that the film is lower than a film formed by the coating method.

JP-A-11-40358 and JP-A-11-54270 disclose a composition (coating liquid) used for producing an organic EL device by an ink-jet method, and a leveling agent is added to the coating liquid. It is described that it may be added. However, these publications do not specifically describe examples of a coating liquid to which a leveling agent is added,
There is no example of the leveling agent.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the above-mentioned problems.
As a result of intensive studies to eliminate the decrease in luminous efficiency, it was found that the above problem can be unexpectedly solved by including a specific amount of a leveling agent, particularly a leveling agent composed of a silicon-based compound or a fluorine-based compound. Heading, the present invention has been completed.

[0007] As in the present invention, a coating liquid for forming an organic EL layer, characterized in that the coating liquid contains a specific amount of a leveling agent, especially a leveling agent comprising a silicon compound or a fluorine compound. By forming at least one organic layer in the organic EL element by an ink-jet method or a printing method, the light-emitting characteristics due to the content of the leveling agent and the life are not reduced.
This makes it possible to form a film having a flat surface. As a result, uneven light emission due to the flatness of the film occurs, and the luminous efficiency and life are reduced compared to a film formed by the spin coating method. It is possible to solve.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the organic EL element (pixel) includes at least a first electrode 2, an organic EL medium 3, and a second electrode 4 on a substrate 1. Here, it is preferable that partition walls 5 are provided on the side walls of the organic EL medium 3 and the second electrode 4. Further, from the viewpoint of contrast, it is preferable that the deflection plate 7 is provided outside the substrate 1, and further from the viewpoint of reliability,
It is preferable that a sealing film or a sealing substrate 6 is provided on the second electrode 4.

As the substrate, an inorganic material substrate such as a quartz substrate and a glass substrate, and a resin substrate such as a polyethylene terephthalate substrate, a polyether sulfone substrate, and a polyimide substrate can be used, but the present invention is not limited to these. Not something.

[0010] The organic EL medium has a structure having at least one organic light emitting layer, a single layer structure of the organic light emitting layer, or a multilayer structure of a charge transport layer (electron transport layer and hole transport layer) and an organic light emitting layer. It may be. Here, each of the charge transport layer and the organic light emitting layer may have a multilayer structure. Also,
If necessary, a buffer layer may be provided between the light emitting layer and the electrode. The organic layer in the present invention means an organic light emitting layer and a charge transport layer that constitute an organic EL medium.

It is preferable that at least one layer of the organic EL medium is formed by an ink-jet method or a printing method using the coating liquid for forming an organic EL layer according to the present invention. May be formed by the method of the present invention, or may be formed by a conventional method such as a dry process such as a vacuum deposition method or a dry process such as a dip coating method or a spin coating method.

Next, the coating liquid for forming an organic EL layer of the present invention will be described. The coating liquid for forming an organic EL layer of the present invention can be broadly classified into a coating liquid for forming a light emitting layer and a coating liquid for forming a charge transport layer.

The coating liquid for forming a light emitting layer may be a known low molecular light emitting material, a high molecular light emitting material, a precursor of a high molecular light emitting material, or both a low molecular light emitting material and a high molecular material used for forming an organic EL device. A light-emitting material such as a contained material and a leveling agent are dissolved or dispersed in a solvent. Hereinafter, the respective materials will be exemplified, but these do not limit the present invention.

Known low molecular light emitting materials include, for example,
Examples include triphenylbutadiene, coumarin, Nile red, oxadiazole derivatives, chelate complexes and the like. Known polymer light emitting materials include, for example, poly (2
-Decyloxy-1,4-phenylene) [DO-PP
P], poly [2,5-bis {2- (N, N, N-triethylammonium) ethoxy} -1,4-phenylene-
Alto-1,4-phenylene] dibromide [PPP-
NEt ₃ ^+], poly [2- (2'-ethylhexyl oxy) -5-methoxy-1,4-phenylene vinylene]
[MEH-PPV], poly [5-methoxy (2-propanoxysulfonide) -1,4-phenylenevinylene]
[MPS-PPV], poly [2,5-bis (hexyloxy-1,4-phenylene) (1-cyanovinylene)]
[CN-PPV], poly [2- (2′-ethylhexyloxy) -5-methoxy-1,4-phenylene- (1-
Cyanovinylene)] [MEH-CN-PPV], poly (dioctylfluorene) (PDF) and the like.

Examples of known polymer light emitting material precursors include, for example, poly (p-phenylene) precursor [Pre
-PPP], poly (p-phenylenevinylene) precursor [Pre-PPV], poly (p-naphthalenevinylene)
Precursor [Pre-PNV] and the like. Known polymer materials include, for example, polycarbonate (P
C), polymethyl methacrylate (PMMA), polycarbazole (PVCz) and the like.

As the leveling agent, a silicon compound, a fluorine compound, a nonionic surfactant, an ionic surfactant, a titanate coupling agent and the like can be used. Among them, a silicon compound and a fluorine compound are preferable. . Examples of the silicon compound include dimethyl silicone, methyl silicone, phenyl silicone, methyl phenyl silicone, alkyl-modified silicone, alkoxy-modified silicone, and polyether-modified silicone. Among them, dimethyl silicone and methyl phenyl silicone are preferable. Examples of the fluorine-based compound include polytetrafluoroethylene, polyvinylidene fluoride, fluoroalkyl methacrylate, perfluoropolyether, and perfluoroalkylethylene oxide. Among them, polytetrafluoroethylene is preferable. As the leveling agent, more specifically, a dimethylsiloxane compound (trade name: KF96L-1, KF96L-5, KF96L-1) manufactured by Shin-Etsu Silicone Co., Ltd.
0, KF96L-100) can be suitably used.

The amount of the leveling agent (L) added is: viscosity of L (cp) × the amount of L added to the luminescent material (wt.
%) <200. Usually, the amount of the leveling agent added is 0.0001 to
30 wt%, preferably 0.001 to 10 wt%
And more preferably 0.1 to 5 wt%.

As a solvent used for dissolving or dispersing the luminescent material as described above, a solvent containing at least one solvent having a vapor pressure of 500 Pa or less at a temperature at the time of forming an organic layer (at the time of transfer) is used. Is preferred. More preferably, from the viewpoint of film surface properties, organic EL
In order to achieve a film thickness suitable for a device, the vapor pressure must be 2
Solvents having a pressure of 50 Pa or less are particularly preferred. When a mixed solvent of two or more different solvents is used, it is preferable to contain 50 wt% or more of a solvent having a vapor pressure of 500 Pa or less. In the case of forming an organic EL medium including a multilayer laminated film, a solvent used for a layer to be formed later is preferably a solvent that does not dissolve a layer formed earlier, in order to prevent mixing of materials between adjacent films. .

Examples of the solvent having a vapor pressure of 500 Pa or less at the temperature for forming the organic layer include, for example, ethylene glycol, propylene glycol, triethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, triethylene glycol monomethyl. Ether, triethylene glycol monoethyl ether, glycerin, N, N-dimethylformamide, N-methyl-2-pyrrolidone, cyclohexanone, methanol, ethanol, 1-propanol,
Examples thereof include octane, nonane, decane, xylene, diethylbenzene, trimethylbenzene, and nitrobenzene. These solvents can also be used as a mixed solvent of two or more kinds.

The coating liquid for forming a light emitting layer may contain, if necessary, an additive for adjusting viscosity; N, N-bis- (3-methylphenyl) -N, N'-bis (phenyl) benzidine [ TPD], N, N'-di (naphthalen-1-yl)-
A known hole transport material for organic EL or organic photoconductor such as N, N'-diphenyl-benzidine [NPD];
3- (4-biphenylyl) -4-phenylene-5-t
-Butylphenyl-1,2,4-triazole [TA
Z], tris (8-hydroxynato) aluminum “A
An electron transporting material such as "lq ₃ "; a dopant such as an acceptor or a donor may be added.

The other coating liquid for forming a charge transport layer of the coating liquid for forming an organic EL layer of the present invention may be a known low molecular charge transport material, polymer charge transport material, precursor of a polymer charge transport material, or A material containing both a low molecular charge transport material and a high molecular material and a leveling agent are dissolved or dispersed in a solvent. Hereinafter, the respective materials will be exemplified, but these do not limit the present invention.

Known low-molecular charge transport materials include, for example, TPD, NPD and oxadiazole derivatives. Known polymer charge transport materials include, for example, polyaniline (PANI), 3,4-polyethylenedioxythiophene (PEDOT), polycarbazole (PVCz), poly (triphenylamine derivative) (P
poly-TPD), poly (oxadiazole derivative)
(Poly-OXZ). Known precursors of the polymer charge transport material include, for example, Pre
-PPV, Pre-PNV and the like. Known polymer materials include, for example, PC, PMMA, PVCz
And the like.

The addition of a leveling agent is also effective in a charge transport layer containing no luminescent material. In such a case, examples of the leveling agent include compounds as exemplified in the coating solution for forming a luminescent layer. Specifically, a leveling agent (trade name: S-145) manufactured by Asahi Kasei Kogyo Co., Ltd. can be suitably used. Like the light emitting layer, the amount of addition preferably satisfies the relational expression represented by L viscosity (cp) × the amount of L added to the charge transporting material (wt%) <200. Usually, the amount of the leveling agent added is 0.000 to the charge transporting material.
1 to 30 wt%, preferably 0.001 to 10 w
t%, more preferably 0.1 to 5 wt%.

As a solvent used for dissolving or dispersing the above-described charge transporting material, a solvent containing at least one solvent having a vapor pressure of 500 Pa or less at a temperature at the time of forming an organic layer (at the time of transfer) is used. It is preferably used. More preferably, a solvent having a vapor pressure of 250 Pa or less is particularly preferable in order to realize a film thickness suitable for an organic EL element from the viewpoint of the surface properties of the film. When a mixed solvent of two or more different solvents is used, it is preferable to contain 50 wt% or more of a solvent having a vapor pressure of 500 Pa or less. As the solvent having a vapor pressure of 500 Pa or less at the temperature at which the organic layer is formed,
Examples of the solvent include those exemplified in the light emitting layer forming coating liquid. In the case of forming an organic EL medium including a multilayer laminated film, a solvent used for a layer to be formed later is preferably a solvent that does not dissolve a layer formed earlier, in order to prevent mixing of materials between adjacent films. .

The coating liquid for forming a charge transporting layer may be added, if necessary, with additives such as viscosity adjusting additives and acceptors and donors as exemplified in the coating liquid for forming a light emitting layer. Good.

The material of the first electrode 2 and the second electrode 4 sandwiching the organic EL medium 3 is selected according to the configuration of the organic EL display. That is, in the organic EL display, when the substrate 1 is a transparent substrate and the first electrode is a transparent electrode, light emission from the organic EL medium 3 is emitted from the substrate 1 side. , Second electrode 4
Is preferably used as a reflective electrode, or a reflective film (not shown) is provided on a surface of the second electrode 4 not adjacent to the organic EL medium. Conversely, when the second electrode 4 is a transparent electrode, light emission from the organic EL medium 3 is emitted from the second electrode 4 side. It is preferable to provide a reflection film (not shown) between the substrate 2 and the substrate 1.

As a material of the transparent electrode, for example, Cu
I, ITO (indium tin oxide), SnO ₂ , ZnO
Examples of the material of the reflective electrode include metals such as aluminum and calcium, alloys such as magnesium-silver and lithium-aluminum, laminated films of metals such as magnesium / silver and magnesium / silver, and fluorine. Examples thereof include a stacked film of an insulator and a metal such as lithium / aluminum, but are not particularly limited thereto.

A first electrode or a second electrode is formed on a substrate or an organic EL medium using the above electrode material. The method is not particularly limited, and sputtering, EB deposition,
A dry process such as resistance heating evaporation is given. Alternatively, the first electrode or the second electrode can be formed by dispersing the above electrode material in a resin and performing a wet process such as a printing method or an inkjet method.

Next, the arrangement of the organic EL elements (pixels) will be described. In the organic EL display of the present invention, for example, as shown in FIG. 2 (a), each part of the display may be composed of areas having different emission colors. The pixels are arranged in a stripe array in which red (R) light emitting pixels 8, green (G) light emitting pixels 9, and blue (B) light emitting pixels 10 are arranged in a matrix as shown in FIG. No. Further, the arrangement of the pixels may be a mosaic arrangement, a delta arrangement, and a square arrangement as shown in FIGS. 2 (c), 2 (d) and 2 (e), respectively. R light emitting pixel 8, G light emitting pixel 9 and B
The ratio of the occupied area of each of the light emitting pixels 10 is shown in FIG.
As shown in (1), it is not always necessary to use 1: 1: 1, and the occupied area of each pixel may be the same or different for each pixel.

It is preferable to provide partitions between pixels having different emission colors in order to prevent mixing of the emission layers. The partition wall may have a single-layer structure or a multilayer structure, may be arranged between pixels, or may be arranged between different emission colors. The material of the partition walls is preferably a solvent in which a luminescent material, a charge transporting material or a polymer material is dissolved or dispersed, that is, a material which is insoluble or hardly soluble in a solvent of the luminescent layer forming coating liquid or the charge transporting layer forming coating liquid. Materials for black matrix (for example, chromium and resin black) in order to improve display quality as a display
It is particularly preferred to use

The barrier ribs have a critical surface tension (γc [dyne / c) smaller than the surface tension of the coating liquid for forming the organic EL layer in order to effectively prevent mixing of the light emitting layers.
m]) are preferred. Specifically, the partition wall may be formed using a material having a small critical surface tension.After the partition wall is formed, plasma treatment, UV treatment, gas treatment, or the like is performed to reduce the critical surface tension of the partition wall. May be.

As a preferable material for forming the partition walls, for example, polyhexafluoropropylene (γc = 16 dy)
ne / cm), polytetrafluoroethylene (γc = 18 dy)
ne / cm), polytetrafluoroethylene (γc = 22 dy)
ne / cm), KBM7103 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., γc = 20 dyne / c) in a positive resist
m), but are not particularly limited thereto.

Next, between the first electrode corresponding to each pixel and the second
A connection method between the electrodes will be described. Organic EL of the present invention
In the display, for example, as shown in FIG. 3A, the first electrode 2 or the second electrode 4 may be an independent electrode for each pixel. Also, as shown in FIG. 3B, whether the first electrode 2 and the second electrode 4 sandwiching the organic EL medium are configured to be striped electrodes orthogonal to each other on the common substrate 1. Alternatively, as shown in FIG. 3C, the first electrode 2 or the second electrode 4 may be connected to a common electrode via a thin film transistor (TFT) 11. In the figure, 12 indicates a source bus line, and 13 indicates a gate bus line.

In the organic EL display of the present invention, a plurality of pixels are arranged in a matrix with the partition walls 5 interposed therebetween, and by giving these pixels a plurality of luminescent colors, full-color display is possible. As the plurality of emission colors, a combination of red, green, and blue is preferable.

Next, a method for forming an organic EL medium (organic layer) according to the present invention will be described in detail. In the method for producing an organic EL device of the present invention, the organic layer of the organic EL device is formed by an inkjet method or a printing method using the coating liquid for forming an organic EL layer of the present invention. Specifically, a coating liquid for forming a light emitting layer is formed on the first electrode or the charge transport layer by an ink jet method or a printing method, and the coating liquid for forming a charge transport layer is formed on the first electrode or the charge transport layer. Over the light-emitting layer.

The ink-jet method may be either a continuous type or an on-demand type. The liquid discharge method is such that a coating liquid in which an organic luminescent material or a precursor of the organic luminescent material is dissolved or dispersed is deteriorated by heat. To prevent this, the piezo method is preferred. The inkjet of the present invention also includes a dispenser and an ultrasonic spray.

Next, formation of the organic layer by the ink jet method will be described. As shown in FIG. 4, the organic layer can be formed by discharging a coating liquid for forming an organic EL layer by an inkjet printing method. When one pixel is formed, only one liquid may be discharged, or multiple liquids may be discharged to the same place or different places. Regarding the manufacture of the organic LE display, it is preferable to use a different nozzle for each emission color as the nozzle for discharging the liquid. Further, it is preferable to use a plurality of nozzles with the same emission color in consideration of the production speed.

Next, formation of an organic layer by a printing method will be described. The printing method is a method in which a coating liquid for forming an organic EL layer is applied to a transfer substrate, and the coating liquid is transferred to the substrate. Examples thereof include conventional methods such as letterpress printing, intaglio printing, lithographic printing, and offset printing. The method of the present invention is not particularly limited. However, in order to uniformly form a thin film having a thickness of 1 μm or less, letterpress printing, intaglio printing, and lithographic printing are preferable.
In order to uniformly form a thin film having a thickness of 1000 ° or less, letterpress printing is preferable.

The structure of the printing apparatus used is shown in FIG.
As shown in FIG. 1, the roll unit 1 for fixing the transfer substrate 16
7 is applied from a coating liquid inlet 14 to a transfer substrate 16 fixed to the coating substrate 7, the coating liquid 18 is directly applied via a blade 15, and the first electrode 2 on the substrate 1 set on the stage 19.
However, in order to make the thickness of the film formed on the substrate 1 uniform, first, as shown in FIG.
8 is applied to a roll section 20 for temporarily holding a coating liquid, and the roll section 20 is transferred to a transfer substrate 16 fixed to another roll section (a roll section for fixing a transfer substrate) 17 and the transfer is performed. It is preferable to transfer the material to the first electrode 2 on the substrate 1. Also, as shown in FIG.
Is applied to a roll section 20 for temporarily holding the coating liquid, the roll section 20 is transferred to another roll section (a roll section for fixing a transfer substrate) 17, and the transferred coating liquid 18 is further transferred to another roll section. The coating liquid 18 is transferred to the transfer substrate 16 fixed to 21, and the transferred coating liquid 18 is transferred to the roll unit 21 again.
Thereafter, it can be transferred to the first electrode 2 on the substrate 1.

The transfer substrate fixed to the roll will be described. The material of the transfer substrate is preferably selected according to the material of the substrate to be used. When the substrate is a resin substrate, the material of the transfer substrate may be either a metal material or a resin material.However, when the substrate is an inorganic material substrate, the material of the transfer substrate is determined in consideration of damage to the substrate. Therefore, a resin material is preferable. Examples of the metal material include a copper plate, and examples of the resin material include APR (product name, manufactured by Asahi Kasei Corporation) and Fuji Trelief (product name, manufactured by Fuji Film Co., Ltd.).
The present invention is not limited by these. Further, as the transfer pattern, an uneven pattern may be simply formed, or a pattern may be formed in a portion having good wettability with respect to the coating liquid and a portion having poor wettability with the coating liquid (a planographic plate may be used).

The environment in which the organic layer is formed by the ink jet method or the printing method is not particularly limited, but is preferably in an inert gas in consideration of moisture absorption of the formed film and deterioration of the organic material.

After the organic layer is formed by an ink jet method or a printing method, it is preferable to carry out heat drying in order to remove the remaining solvent. The environment in which the drying is performed is not particularly limited, but is preferably in an inert gas and preferably under reduced pressure in consideration of moisture absorption of the formed film and deterioration of the organic material.

[0043]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited by these examples.

<Film Forming Test by Printing Apparatus> (Comparative Example 1) 1 g of poly (dioctylfluorene) (PDF) as a light emitting material was vaporized with trimethylbenzene (vapor pressure at a temperature (28 ° C. when an organic layer was formed (28 ° C.): 247 P)).
a) Dissolved in 100 ml to prepare a blue light emitting layer forming coating liquid (surface tension: 27.8 mN / m), and the viscosity of the obtained coating liquid was measured. Next, the prepared coating liquid was transferred to a glass substrate using an ink jet device (nozzle diameter: 50 μm) and a letterpress printing device (300 lines / inch as anilox roll) to produce a film. In printing, APR (Shore A hardness 55) is used as a transfer substrate.
And the printing pressure was 0.1 mm.

The surface properties of the produced films were evaluated. That is, the film thickness was measured at 20 points at 5 mm intervals, and the distribution and average value were determined. The obtained result is
The results are shown in Table 1 together with the viscosity of the coating liquid.

(Example 1) As a leveling agent, an amount corresponding to 0.01 wt% with respect to 1 g of PDF of the luminescent material,
That is, 0.0001 g of KF96L-1 (manufactured by Shin-Etsu Silicone Co., Ltd., surface tension: 16.9 mN / m, boiling point: 1)
(53 ° C.) was added to the blue light-emitting layer forming coating liquid, and a blue light-emitting layer forming coating liquid was prepared in the same manner as in Comparative Example 1. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Example 2) As a leveling agent, KF96L-1 was added to the blue luminescent layer forming coating solution in an amount corresponding to 0.1 wt% relative to 1 g of PDF of the luminescent material, that is, 0.001 g. Instead of trimethylbenzene, a mixed solvent of trimethylbenzene-xylene having a mixture ratio of 7: 3 (vapor pressure at a temperature (28 ° C.) at which an organic layer is formed: trimethylbenzene 247 Pa, xylene 88
A blue light emitting layer forming coating liquid was prepared in the same manner as in Comparative Example 1 except that 0 Pa) was used. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film,
The surface properties of the obtained film were evaluated. The obtained results, the trade name of the leveling agent, the amount added and the viscosity,
Table 1 shows the viscosity of the coating liquid before the addition of the leveling agent.

(Examples 3 to 5) As leveling agents, 1 wt% and 10 watts were respectively used for 1 g of PDF of a light emitting material.
t% and an amount corresponding to 20 wt%, ie, 0.01
g, 0.1 g, and 0.2 g of KF96L-1 were added to the blue light emitting layer forming coating liquid in the same manner as in Comparative Example 1 to prepare a blue light emitting layer forming coating liquid. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

Examples 6 to 10 As leveling agents,
0.01wt each for 1g of PDF of light emitting material
%, 0.1 wt%, 1 wt%, 10 wt% and 20 w
%, ie 0.0001 g, 0.00%
1 g, 0.01 g, 0.1 g and 0.2 g of KF96
L-5 (manufactured by Shin-Etsu Silicone Co., Ltd., surface tension: 19.7)
mN / m, boiling point: 200 ° C. or more) was prepared in the same manner as in Comparative Example 1 except that the coating liquid for forming a blue light emitting layer was added. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

Comparative Example 2 KF96L-5 (Shin-Etsu Silicone Co., Ltd.) was used as a leveling agent in an amount corresponding to 40 wt% with respect to 1 g of PDF of the luminescent material, ie, 0.4 g.
In the same manner as in Comparative Example 1, except that the following components were added to the coating solution for forming a blue light-emitting layer: surface tension: 19.7 mN / m, boiling point: 200 ° C. or higher. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Examples 11 to 14) As a leveling agent, 0.01 w each was added to 1 g of PDF of a light emitting material.
%, 0.1 wt%, 1 wt% and 10 wt%, ie 0.0001 g, 0.001 g, 0.
01 g and 0.1 g of KF96L-10 (manufactured by Shin-Etsu Silicone Co., Ltd., surface tension: 20.1 mN / m, boiling point: 2)
(00 ° C. or higher) was added to the blue light-emitting layer forming coating liquid in the same manner as in Comparative Example 1 to prepare a blue light-emitting layer forming coating liquid. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Comparative Example 3) As a leveling agent, an amount corresponding to 20 wt% with respect to 1 g of PDF of the luminescent material, that is, 0.2 g of KF96L-10 (manufactured by Shin-Etsu Silicone Co., Ltd., surface tension: 20.1 mN / m) , Boiling point: 200
(° C. or more) was added to the coating solution for forming a blue light emitting layer in the same manner as in Comparative Example 1 except that the coating solution for forming a blue light emitting layer was prepared. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Examples 15 and 18) As a leveling agent, 0.001 to 1 g of PDF of a luminescent material was used.
wt%, 0.01 wt%, 0.1 wt% and 1 wt%
Ie, 0.00001 g, 0.000
1 g, 0.001 g and 0.01 g of KF96L-1
00 (manufactured by Shin-Etsu Silicone Co., Ltd., surface tension: 20.9 m)
N / m, boiling point: 200 ° C. or higher) was prepared in the same manner as in Comparative Example 1 except that the coating liquid for forming a blue light emitting layer was added. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Comparative Example 4) As a leveling agent, an amount corresponding to 2 wt% with respect to 1 g of PDF of the luminescent material, that is, 0.02 g of KF96L-100 (Shin-Etsu Silicone Co., Ltd., surface tension: 20.9 mN / m) , Boiling point: 200
(° C. or more) was added to the coating solution for forming a blue light emitting layer in the same manner as in Comparative Example 1 except that the coating solution for forming a blue light emitting layer was prepared. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 1, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

Comparative Example 5 1 g of 3,4-polyethylenedioxythiophene (PEDOT) / polystyrenesulfonate (PSS) as a hole transport material was mixed with a pure water-ethylene glycol mixed solution (organic layer) at a mixing ratio of 6: 4. Vapor pressure at the temperature at the time of formation of the powder: 7 Pa, surface tension: 53.3 mN / m) 100 m
1 to prepare a coating liquid for forming a hole transport layer, and the viscosity of the obtained coating liquid was measured. Next, the prepared coating liquid was transferred to a glass substrate using a modified version of a commercially available inkjet printer and a letterpress printing device (300 lines / inch as anilox roll) to produce a film.
In printing, APR (Shore A) is used as a transfer substrate.
The printing pressure was 0.1 mm using a hardness of 55).

The surface properties of the produced films were evaluated. That is, the film thickness was measured at 20 points at 5 mm intervals, and the distribution and average value were determined. The obtained result is
The results are shown in Table 1 together with the viscosity of the coating liquid.

(Example 19) As a leveling agent, 0.01 w per 1 g of PEDOT / PSS of a hole transport material was used.
%, ie 0.0001 g of S-14
5 (manufactured by Asahi Kasei Corporation, surface tension: 16.5 mN /
m) to the coating solution for forming a hole transport layer, a methanol-ethylene glycol mixed solvent having a mixing ratio of 6: 4 instead of the pure water-ethylene glycol mixed solution (at a temperature at the time of forming an organic layer: methanol A coating liquid for forming a hole transport layer was prepared in the same manner as in Comparative Example 5 except that 12300 Pa and ethylene glycol 7 Pa) were used. The viscosity of the coating liquid before the addition of the leveling agent was measured. Comparative Example 5
In the same manner as described above, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

Examples 20 to 23 As leveling agents, 0.1% by weight, 1% by weight, 10% by weight and 20% by weight with respect to 1 g of PEDOT / PSS of a hole transporting material, respectively.
wt.%, ie 0.001 g, 0.01
g, 0.1 g and 0.2 g of S-145 in the same manner as in Comparative Example 5 except that
A coating liquid for forming a hole transport layer was prepared. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 5, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties.
The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

(Comparative Example 6) As a leveling agent, an amount equivalent to 30% by weight based on 1 g of PEDOT / PSS of the hole transport material, that is, 0.3 g of S-145 was added to the coating liquid for forming a hole transport layer. A coating solution for forming a hole transport layer was prepared in the same manner as in Comparative Example 5 except that the coating was performed. The viscosity of the coating liquid before the addition of the leveling agent was measured. In the same manner as in Comparative Example 5, the prepared coating liquid was transferred to a glass substrate to prepare a film, and the obtained film was evaluated for surface properties. The obtained results are shown in Table 1 together with the brand name, amount and viscosity of the leveling agent, and the viscosity of the coating liquid before the addition of the leveling agent.

[0060]

[Table 1]

From the results shown in Table 1, it can be seen that the surface of the film can be made flat by adding a leveling agent comprising a silicon compound or a fluorine compound to the coating solution.

Comparative Example 7 A pattern electrode made of ITO having a pitch of 4 mm and a width of 2 mm was formed as a first electrode on a glass substrate with ITO having a thickness of 150 nm by photolithography. Next, the substrate is cleaned by a conventional wet process (isopropyl alcohol, acetone and pure water), and further cleaned by a conventional dry process (UV
(Ozone treatment and plasma treatment). IT
Using a PEDOT / PSS aqueous solution, a hole transport layer having a thickness of 50 nm was formed on a glass substrate with O by a spin coating method, and dried by heating at 200 ° C. for 5 minutes in a nitrogen atmosphere.

A coating solution for forming a blue light emitting layer was prepared by dissolving 1 g of PDF as a light emitting material in 100 ml of trimethylbenzene. Next, a 50 nm-thick blue light-emitting layer was formed by spin coating using a coating solution prepared on the glass substrate with ITO on which the hole transport layer was formed, and dried by heating at 160 ° C. for 2 hours in a nitrogen atmosphere. . Next, a shadow mask having a hole with a width of 2 mm × 100 mm was fixed to the substrate in a direction perpendicular to the ITO, and the substrate was put into a vacuum evaporation apparatus, and Ca was dried to 50 nm under a vacuum of 1 × 10 ⁻⁶ Torr.
Ag was vacuum-deposited with a thickness of 300 nm to form a second electrode (counter electrode).

With respect to the fabricated device, the electrical characteristics (10
Luminance in V, cd / m ² ) and half-life (initial 100
cd / m ² ) was evaluated. Table 2 shows the obtained results.

Comparative Example 8 A pattern electrode made of ITO having a pitch of 4 mm and a width of 2 mm was formed as a first electrode on a glass substrate with ITO having a thickness of 150 nm by photolithography. Next, the substrate is cleaned by a conventional wet process (isopropyl alcohol, acetone and pure water), and further cleaned by a conventional dry process (UV
(Ozone treatment and plasma treatment). IT
Using a PEDOT / PSS aqueous solution, a hole transport layer having a thickness of 50 nm was formed on a glass substrate with O by a spin coating method, and dried by heating at 200 ° C. for 5 minutes in a nitrogen atmosphere.

1 g of PDF as a light emitting material was dissolved in 100 ml of trimethylbenzene to prepare a coating liquid for forming a blue light emitting layer. Next, an inkjet device (nozzle diameter:
20 μm) and letterpress printing device (aniloc roll: 3)
00 line / inch) to form a hole transport layer.
The prepared coating solution was transferred onto a glass substrate with TO to form a blue light-emitting layer having a thickness of 50 nm,
The mixture was dried by heating at 2 ° C. for 2 hours. Next, the IT
Fix a shadow mask with a hole of 2 mm x 100 mm width in a direction orthogonal to O, put it in a vacuum evaporation apparatus,
Under a vacuum of 10 ^-6 Torr, Ca is 50 nm and Ag is 30 nm.
Vacuum evaporation was performed to a thickness of 0 nm to form a second electrode (counter electrode).

The electrical characteristics (10
Luminance in V, cd / m ² ) and half-life (initial 100
cd / m ² ) was evaluated. Table 2 shows the obtained results.

(Examples 24 to 33) Devices were produced in the same manner as in Comparative Example 8 except that the coating solutions prepared in Examples 1 to 10 were used as the coating solution for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

Comparative Example 9 A device was prepared in the same manner as in Comparative Example 8 except that the coating liquid prepared in Comparative Example 2 was used as the coating liquid for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Examples 34 to 37) Devices were produced in the same manner as in Comparative Example 8, except that the coating solutions prepared in Examples 11 to 14 were used as the coating solution for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Comparative Example 10) An element was produced in the same manner as in Comparative Example 8, except that the coating liquid prepared in Comparative Example 3 was used as a coating liquid for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Examples 38 to 41) Devices were prepared in the same manner as in Comparative Example 8 except that the coating solutions prepared in Examples 15 to 18 were used as the coating solution for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

Comparative Example 11 A device was prepared in the same manner as in Comparative Example 8 except that the coating liquid prepared in Comparative Example 4 was used as the coating liquid for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Comparative Example 12) A pattern electrode made of ITO having a pitch of 4 mm and a width of 2 mm was formed as a first electrode on a glass substrate with ITO having a thickness of 150 nm by photolithography. Next, the substrate is cleaned by a conventional wet process (isopropyl alcohol, acetone and pure water), and further cleaned by a conventional dry process (UV
(Ozone treatment and plasma treatment). PE
1 g of DOT / PSS was dissolved in 100 ml of a mixed solvent of methanol and ethylene glycol at a mixing ratio of 6: 4 to prepare a coating liquid for forming a hole transport layer. Next, the prepared coating liquid was transferred onto a glass substrate with ITO using an ink jet device (nozzle diameter: 20 μm) and a letterpress printing device (anilo roll: 300 lines / inch) to obtain a film thickness of 50 n.
m of the hole transport layer was formed.

A coating solution for forming a blue light emitting layer was prepared by dissolving 1 g of PDF as a light emitting material in 100 ml of trimethylbenzene. Next, a 50-nm-thick blue light-emitting layer was formed on the glass substrate with ITO on which the hole transport layer was formed by spin coating. Next, the ITO
A shadow mask with a hole of 2 mm x 100 mm width was fixed in the direction orthogonal to
Ca is 50 nm and Ag is 300 under a vacuum of 0 ^-6 Torr.
The second electrode (counter electrode) was formed by vacuum evaporation. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Examples 42 to 46) Devices were produced in the same manner as in Comparative Example 8 except that the coating solutions prepared in Examples 19 to 23 were used as the coating solution for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

(Comparative Example 13) An element was produced in the same manner as in Comparative Example 8, except that the coating liquid prepared in Comparative Example 6 was used as the coating liquid for forming a blue light emitting layer. In the same manner as in Comparative Example 8, the manufactured device was evaluated for electrical characteristics and half-life. Table 2 shows the obtained results.

[0078]

[Table 2]

From the results shown in Table 2, it was found that the film formed by the ink-jet method or the printing method was replaced with the film formed by the spin-coating method by adding a leveling agent comprising a silicon compound or a fluorine compound to the coating liquid. It can be seen that problems such as a decrease in luminous efficiency and life can be solved. Further, it can be seen that the following constant relationship exists between the viscosity of the leveling agent and the amount of addition that does not cause a decrease in luminous efficiency or life. L viscosity (cp) × the amount of L added to the light emitting material or the charge transporting material (wt%) <200 That is, the lower the viscosity of the leveling agent, the more the leveling agent can be added. And a reduction in the service life can be prevented.

Example 47 An ITO transparent stripe electrode having a pitch of 120 μm and a width of 100 μm was formed as a first electrode on a glass substrate with ITO having a thickness of 130 nm by photolithography. Next, the substrate was washed by a conventional wet process (isopropyl alcohol, acetone and pure water), and further washed by a conventional dry process (UV ozone treatment and plasma treatment).

Next, a critical surface tension of 10 d
A negative photosensitive resin containing yne / cm of a surface tension adjusting agent (trade name: CYTOP CTL, manufactured by Asahi Glass Co., Ltd.) was coated to a film thickness of 4 μm by spin coating. Next, mask exposure is performed, and the residue of the resist film is washed away.
A pitch of 120 μm and a width of 40 μm in a direction orthogonal to O
Was obtained.

Next, an ink jet apparatus (nozzle diameter: 2)
0 μm) and PE having a surface tension of 40 dyne / cm
A coating liquid for forming a hole transport layer of a DOT / PSS aqueous solution was discharged to each pixel, and subsequently heated and dried at 90 ° C. for 30 minutes under vacuum to form a hole transport layer having a thickness of 75 nm.

Further, a poly [2,5-bis (hexyloxy-1,4-phenylene) (1-cyanovinylene)] precursor (Pre-CN-PPV) as a red light-emitting material and an Leveling agent KF96L in an amount equivalent to 0.1 wt% based on the light emitting material
-1 and a mixed solvent of methanol and diethylene glycol having a mixing ratio of 4: 6 (at the temperature at which an organic layer is formed: methanol 12300 Pa, diethylene glycol 2P
a) a coating solution for forming a red light-emitting layer dissolved in a), a poly (p-phenylenevinylene) precursor (Pre
-PPV) and a leveling agent KF96L-1 in an amount corresponding to 0.1 wt% with respect to the light emitting material, at a mixing ratio of 6:
4, a coating liquid for forming a green light-emitting layer dissolved in a mixed solvent of methanol and ethylene glycol, poly (dioctylfluorene) (PDF) as a blue light-emitting material, and an amount of 0.1 wt% based on the light-emitting material. Agent
A coating solution for forming a blue light-emitting layer in which KF96L-1 was dissolved in trimethylbenzene was applied by patterning. The surface tension of each coating solution used was 30 dyne / cm.

After forming the coating films, these were dried by heating to obtain a light emitting layer having a thickness of 110 nm. The coating film containing PDF was heated and dried at 100 ° C. for 1 hour. Also, Pre-C
For coating films containing N-PPV and Pre-PPV,
It was heat-treated at 150 ° C. for 6 hours in an Ar atmosphere, and was converted into CN-PPV and PPV simultaneously with drying. As is clear from the relationship between the critical surface tension of the partition walls and the surface tension of each light-emitting layer forming coating liquid, each light-emitting layer forming coating liquid has a different luminescent color due to poor wettability with respect to the partition walls. Mixing of the light emitting layers between the light emitting pixels could be effectively prevented.

Next, Al and Li were co-evaporated using a shadow mask having a thickness of 0.2 μm, a width of 270 μm, and a pitch of 300 nm to form an AlLi alloy electrode as a second electrode. Finally, the obtained device was sealed with an epoxy resin to produce an organic EL display.

When a pulse voltage of 30 V was applied to the organic EL device obtained as described above and the light emission state was observed, light emission was obtained from all the pixels, and the first electrode and the second electrode
No short circuit occurred between the electrodes, between the first electrodes, and between the second electrodes, and no color mixing due to mixing of the light emitting layers was observed. Further, non-uniform light emission in the pixel due to non-uniform thickness of the light emitting layer and the charge transport layer was not observed.

Example 48 An ITO transparent stripe electrode having a pitch of 120 μm and a width of 100 μm was formed as a first electrode on a glass substrate with ITO having a thickness of 130 nm by photolithography. Next, the substrate was washed by a conventional wet process (isopropyl alcohol, acetone and pure water), and further washed by a conventional dry process (UV ozone treatment and plasma treatment).

Next, a critical surface tension of 10 d
A negative photosensitive resin containing yne / cm of a surface tension adjusting agent (trade name: CYTOP CTL, manufactured by Asahi Glass Co., Ltd.) was coated to a film thickness of 4 μm by spin coating. Next, mask exposure is performed, and the residue of the resist film is washed away.
A pitch of 120 μm and a width of 40 μm in a direction orthogonal to O
Was obtained.

Next, a letterpress printing device (anilo roll:
Surface tension of 40 dyne using 300 lines / inch)
/ Cm 2 of a PEDOT / PSS aqueous solution was transferred, and then dried by heating at 90 ° C for 30 minutes under vacuum to form a hole transport layer having a thickness of 75 nm.

Further, using a relief printing apparatus, Pre-CN-PPV as a red light-emitting material and a leveling agent KF9 in an amount corresponding to 0.1 wt% based on the light-emitting material.
6L-1 in a mixed solvent of methanol and diethylene glycol at a mixing ratio of 6: 4, a red light-emitting layer forming coating solution, Pre-PPV as a green light-emitting material, and an amount corresponding to 0.1 wt% based on the light-emitting material. Leveling agent KF9
6L-1 in a mixed solvent of methanol and ethylene glycol at a mixing ratio of 6: 4, a green light emitting layer forming coating solution, PDF as a blue light emitting material, and an amount corresponding to 0.1 wt% based on the light emitting material. Leveling agent KF96L
-1 was dissolved in trimethylbenzene, and a blue light emitting layer forming coating solution was applied by patterning. The surface tension of each coating solution used was 30 dyne / cm.

After forming the coating films, these were heated and dried to obtain a light emitting layer having a thickness of 110 nm. The coating film containing PDF was heated and dried at 100 ° C. for 1 hour. Also, Pre-C
For coating films containing N-PPV and Pre-PPV,
It was heat-treated at 150 ° C. for 6 hours in an Ar atmosphere, and was converted into CN-PPV and PPV at the same time as drying. As is clear from the relationship between the critical surface tension of the partition walls and the surface tension of each light-emitting layer forming coating liquid, each light-emitting layer forming coating liquid has a different luminescent color due to poor wettability with respect to the partition walls. Mixing of the light emitting layers between the light emitting pixels could be effectively prevented.

Next, Al and Li were co-evaporated using a shadow mask having a thickness of 0.2 μm, a width of 270 μm, and a pitch of 300 nm to form an AlLi alloy electrode as a second electrode. Finally, the obtained device was sealed with an epoxy resin to produce an organic EL display.

When a pulse voltage of 30 V was applied to the organic EL device obtained as described above and the light emission state was observed, light emission was obtained from all the pixels, and the first electrode and the second electrode
No short circuit occurred between the electrodes, between the first electrodes, and between the second electrodes, and no color mixing due to mixing of the light emitting layers was observed. Further, non-uniform light emission in the pixel due to non-uniform thickness of the light emitting layer and the charge transport layer was not observed.

[0094]

According to the present invention, it is possible to form an organic film having excellent flatness by an ink-jet method or a printing method. It can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an organic EL device of the present invention.

FIG. 2 is a schematic partial plan view of an arrangement of a light emitting layer of the organic EL display of the present invention.

FIG. 3 is a schematic partial plan view of an arrangement of electrodes of the organic EL display of the present invention.

FIG. 4 is a schematic view of a step of forming a light-emitting layer by an inkjet method in the organic EL display of the present invention.

FIG. 5 is a schematic partial sectional view of a printing apparatus for an organic EL display of the present invention.

FIG. 6 is a schematic partial sectional view of a printing apparatus for an organic EL display of the present invention.

FIG. 7 is a schematic partial sectional view of a printing apparatus for an organic EL display according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Substrate 2 1st electrode 3 Organic EL medium (organic layer) 4 2nd electrode 5 Partition 6 Sealing film or substrate 7 Deflection plate 8 Red (R) light emitting pixel 9 Green (G) light emitting pixel 10 Blue (B) Light-emitting pixel 11 Thin-film transistor (TFT) 12 Source bus line 13 Gate bus line 14 Coating liquid inlet 15 Blade 16 Transfer substrate 17 Roll part for fixing transfer substrate 18 Coating liquid 19 XY stage 20 Roll part for temporarily holding coating liquid (Anilox roll) 21 roll part 22 inkjet printer head

Claims (5)

[Claims] 1. An organic EL layer forming coating liquid used for forming an organic layer of an organic EL element, wherein the coating liquid contains a leveling agent and a luminescent material or a charge transport material.
The organic EL device according to claim 1, wherein the amount of the leveling agent (L) satisfies a relational expression represented by: L viscosity (cp) × the amount of L added to the light emitting material or the charge transporting material (wt%) <200. Coating liquid for forming a layer. 2. The coating liquid for forming an organic EL layer according to claim 1, which contains a solvent having a vapor pressure of 500 Pa or less at a temperature at which the organic layer is formed. 3. An organic EL device, wherein an organic layer of an organic EL element is formed by an inkjet method or a printing method using the coating liquid for forming an organic EL layer according to claim 1 or 2.
Manufacturing method of L element. 4. A leveling agent, wherein at least one of the organic layers of the organic EL device is formed using the coating liquid for forming an organic EL layer according to claim 1 or 2, and is made of a silicon compound or a fluorine compound. An organic EL device comprising: 5. The organic EL device according to claim 4, comprising a partition having a critical surface tension smaller than the surface tension of the coating liquid for forming an organic EL layer.