JP2012079897A - Method of manufacturing organic electroluminescent display device, and organic electroluminescent display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing an organic electroluminescent display device, along with an organic electroluminescent display device manufactured by the method, which includes applying of liquid material containing organics (application liquid) on a pixel region separated by a bank provided on a substrate, by an ink jet method or the like, which can reduce the amount of organics sticking to the bank.SOLUTION: There is provided a method of manufacturing an organic electroluminescent display device which uses an application liquid containing liquid organics or the organics having mesomorphism as well as a bank having a curvature. In the method, a predetermined relationship of contact angle against pure water is satisfied. There is also provided an organic electroluminescent display device manufactured by the method.

Description

  The present invention relates to a method for manufacturing an organic light emitting display device and an organic light emitting display device.

  As devices using organic materials, researches on organic electroluminescent elements (hereinafter also referred to as OLEDs and organic EL elements), transistors using organic semiconductors, and the like are being actively conducted. In particular, the organic electroluminescence device is expected to be developed as a lighting application as a solid light-emitting large-area full-color display device or an inexpensive large-area surface light source. In general, an organic electroluminescent element is composed of an organic layer including a light emitting layer and a pair of counter electrodes sandwiching the organic layer. When a voltage is applied to such an organic electroluminescence device, electrons are injected from the cathode and holes are injected from the anode into the organic layer. The electrons and holes recombine in the light emitting layer, and light is emitted by releasing energy as light when the energy level returns from the conduction band to the valence band.

An organic EL element can be produced by forming a light emitting layer and other organic layers by, for example, a dry method such as vapor deposition or a wet method such as coating. However, wet methods are attracting attention from the viewpoint of productivity. ing. As one form of the wet method, there is a method of forming a thin film pattern by filling a liquid material containing an organic compound using an ink jet method or a nozzle printing method. However, in this case, there is a problem that the discharged liquid material flows out to adjacent pixels.
In order to solve such a problem, usually, a convex partition member (also referred to as “bank” or “convex portion”) that partitions different thin film regions is provided, and a liquid that forms a different thin film in a pixel region surrounded by the partition member. A method of filling the material is employed. However, when a coating solution containing an organic compound is formed by an ink jet method or a nozzle printing method, there arises a problem that an organic substance adheres to a bank (for example, an insulating film) that divides pixels due to landing positional deviation or the like. In order to deal with such problems, attempts have been made to reduce the amount of organic substances deposited by imparting liquid repellency to the bank or controlling the ink jet driving method.

For example, in Patent Document 1, in the thin film forming method using the bank as described above, the width and height of the bank, the width of the coated region (pixel region), and the droplet diameter of the liquid material forming the thin film layer are described. A method for satisfying a predetermined condition and a method for modifying the bank surface to impart liquid repellency are disclosed. Disclosed is a technique for preventing a situation in which a liquid material flows over a bank by applying a liquid material to the pixel region delimited by the bank using an ink-jet method and forming a film using such a devised bank. Has been.
However, the organic substance used in Patent Document 1 is a polymer or the like, and when the organic substance adheres to the bank, the organic substance is difficult to flow out of the bank, and the organic substance to be formed in the pixel region is a problem. There is a need for improvement. Further, Patent Document 1 does not describe a technique for reducing the amount of organic matter attached to the bank by selecting the organic matter.

Japanese Patent No. 3328297

  In a method of forming a film by applying a liquid material (coating liquid) containing an organic substance to a pixel region divided by the bank by an ink jet method or the like in a pixel region divided by the bank, the organic substance to the bank is compared with the conventional technique. There is a need to further reduce the amount of adhesion.

An object of the present invention is to solve the conventional problems and achieve the following objects.
That is, the present invention provides an organic electroluminescence display device including a bank on a substrate and applying a liquid material (coating liquid) containing an organic substance to a pixel region partitioned by the bank by an inkjet method or the like. It is an object of the present invention to provide a method for manufacturing an organic light emitting display device that can reduce the amount of organic substances attached to a bank.
Another object of the present invention is to provide an organic light emitting display device manufactured by the method for manufacturing the organic light emitting display device.

  In view of the above situation, the present inventors have conducted intensive research and found that a coating liquid containing a liquid organic material or a liquid crystal organic material and a bank having a curvature are used, and a contact angle with respect to pure water will be described later. It has been found that the above-mentioned problems can be solved by satisfying a predetermined relationship.

  That is, the means for solving the problems are as follows.

[1] A method of manufacturing an organic light emitting display device including a patterning substrate having a bank having a curvature and a pixel region partitioned by the bank on a substrate,
A coating liquid containing a liquid organic material or a liquid crystalline organic material is applied to the pixel region in a pattern, and a contact angle θ1 with respect to pure water of a coating surface on which the coating liquid is applied, the coating A method of manufacturing an organic light emitting display device, wherein a contact angle θ2 of a film formed from a liquid with respect to pure water and a contact angle θ3 of the bank with pure water satisfy a relationship of the following formulas (1) and (2).
| Θ2-θ1 | <| θ3-θ2 | Formula (1)
θ2 <θ3 Formula (2)
[2] Contact angle θ1 with respect to pure water of the coating surface on which the coating liquid is applied ≦ contact angle θ2 with respect to pure water of a film formed from the coating liquid <contact angle θ3 with respect to pure water of the bank [1] A method for producing an organic light emitting display device according to [1].
[3] The method for manufacturing an organic electroluminescence display device according to the above [1] or [2], comprising heating the patterning substrate after applying the coating solution.
[4] The method for manufacturing an organic electroluminescence display device according to [3], wherein the heating of the patterning substrate is performed at 80 ° C. to 220 ° C.
[5] The method for manufacturing an organic light emitting display device according to any one of [1] to [4], wherein the bank does not have a flat portion.
[6] The method for producing an organic electroluminescence display device according to any one of [1] to [5], wherein the liquid organic material or liquid crystalline organic material is a light emitting layer forming material.
[7] The method for manufacturing an organic electroluminescence display device according to [6], wherein the coating liquid is applied onto a hole injection layer or a hole transport layer formed in the pixel region.
[8] The coating surface on which the coating solution is applied is a surface of a hole injection layer or a hole transport layer, and a contact angle θ4 of the hole injection layer or the hole transport layer with respect to pure water, and the θ2 and θ3 The method for producing an organic electroluminescence display device according to the above [7], in which satisfies the relationship of the following formula (3).
| Θ2-θ4 | <| θ3-θ2 | Equation (3)
[9] Contact angle θ4 of the hole injection layer or hole transport layer with respect to pure water ≦ contact angle θ2 of the film formed from the coating solution with respect to pure water <contact angle θ3 with respect to pure water of the bank [8] The method for producing an organic electroluminescence display device according to [8].
[10] The organic material according to any one of [1] to [9], wherein the coating liquid contains an organic substance having liquid crystallinity, and the organic substance having liquid crystallinity is a triphenylene derivative having liquid crystallinity. A method for manufacturing an electroluminescent display device.
[11] The organic material according to any one of [1] to [10], wherein the coating liquid contains an organic substance having liquid crystallinity, and the organic substance having liquid crystallinity is a pyrene derivative having liquid crystallinity. A method for manufacturing an electroluminescent display device.
[12] The above coating liquid according to any one of [1] to [9], wherein the coating liquid contains a liquid organic substance, and the liquid organic substance has a melting point in the range of 80 ° C to 220 ° C. Manufacturing method of organic electroluminescence display device.
[13] The method for producing an organic electroluminescence display device according to [12], wherein the organic substance having a melting point in the range of 80 ° C to 220 ° C is a carbazole derivative having an asymmetric structure.
[14] The method for producing an organic electroluminescence display device according to [13], wherein the carbazole derivative having an asymmetric structure is represented by the following general formula (ACz).

In the general formula (ACz), R _As represents a tert-butyl group, a tert-amyl group, or a trimethylsilyl group.
[15] An organic electroluminescent display device manufactured by the method for manufacturing an organic electroluminescent display device according to any one of [1] to [14].

  According to the present invention, an organic electroluminescence display device including a bank on a substrate and applying a liquid material (coating liquid) containing an organic substance to a pixel region partitioned by the bank by an inkjet method or the like. In the method, it is possible to provide a method of manufacturing an organic light emitting display device capable of reducing the amount of organic substances attached to the bank. In addition, according to the present invention, an organic light emitting display device manufactured by the method for manufacturing the organic light emitting display device can be provided.

It is the schematic which shows an example of a structure of the patterning board | substrate which concerns on this invention. It is the schematic which shows an example of the structure by which the positive hole injection layer or the positive hole transport layer was formed in the pixel area | region of the patterning board | substrate which concerns on this invention, and also the light emitting layer was formed on it. FIG. 3 is a diagram illustrating a configuration example of a top emission type organic light emitting display device.

  Hereinafter, the present invention will be described in detail. In the present specification, “to” indicates a range including the numerical values described before and after the minimum and maximum values, respectively.

An organic light emitting display device manufacturing method of the present invention is a method of manufacturing an organic light emitting display device including a patterning substrate having a bank having a curvature and a pixel region partitioned by the bank on a substrate. A coating liquid containing a liquid organic material or a liquid crystal organic material is applied in a pattern to the pixel region, and a contact angle θ1 with respect to pure water of a coating surface on which the coating liquid is applied, The contact angle θ2 with respect to pure water of the film formed from the coating solution and the contact angle θ3 with respect to pure water of the bank satisfy the relationship of the following expressions (1) and (2).
| Θ2-θ1 | <| θ3-θ2 | Formula (1)
θ2 <θ3 Formula (2)

“Applying the coating liquid in a pattern” means that the coating liquid according to the present invention is applied along the pattern of the pixel region formed on the substrate.
Examples of the pixel area pattern include a conventionally known pixel area pattern applied in an organic light emitting display device.
The reason why the amount of organic matter attached to the bank can be reduced by the method of the present invention is not clear, but is presumed as follows.
By using a liquid organic substance or an organic substance having liquid crystallinity as the organic substance, the coating liquid containing these organic substances has a lower viscosity than the case of containing an organic substance other than the above such as a polymer as the organic substance. Such coating liquid has self-healing properties. Specifically, the coating liquid is naturally repaired so as to form a horizontal liquid surface due to the characteristics of self-leveling. There is a tendency to move to the coating liquid body due to the difference in hydrophilicity and hydrophobicity. As a result, the amount of droplets adhering to the bank is reduced, the loss of organic matter is small, and the coating liquid can be used for forming a thin film.
In addition, since the bank according to the method of the present invention has a curvature, the droplets attached to the bank can move to the pixel region along the curved surface, and compared with the case where the bank adheres to the flat surface, Since it is difficult for the droplets to stay, it is presumed that the adhesion of organic substances to the bank is further reduced.
Furthermore, since the contact angle with respect to pure water satisfies the above relationship, the affinity of the coating liquid containing an organic substance (that is, the oil phase) is greater with respect to the coated surface on which the coating liquid is coated than with the bank. This increases the tendency of the coating liquid to move to the coating surface.

In the method of the present invention, it is preferable to heat the patterning substrate after application of the coating solution in order to promote the effect of self-leveling.
In this case, the heating to the patterning substrate is preferably performed at 30 ° C to 250 ° C, more preferably 80 ° C to 220 ° C, and further preferably 80 ° C to 150 ° C.

  Hereinafter, the structure concerning the manufacturing method of the organic electroluminescent display apparatus of this invention is demonstrated.

[1] Patterning Substrate A patterning substrate according to the present invention will be described with reference to FIG. The patterning substrate 21 includes a substrate 22, a bank 23 having a curvature formed on the substrate 22, and a pixel region 24 partitioned by the bank 23. In FIG. 1, the entire bank 23 is located on the substrate 22, but the present invention is not limited to this, and at least a part of the bank 23 may be located on the substrate 22. Although not shown in the present application, the pixel region 24 is surrounded by the bank 23, and the adjacent pixel regions 24 are all partitioned by the bank 23.
As the formation pattern of the pixel region, a conventionally known pixel region pattern used in the organic light emitting display device as described above can be applied.

  Examples of the material of the substrate 22 include glass, PET, PEN, PC, and PSF. Moreover, on these substrates, an oxide semiconductor such as ITO, IZO, ZnO, etc. as a transparent electrode, an electrode layer such as a metal such as silver or gold, or an alloy thereof, and PEDOT / PSS, polyarylamine as a hole injection layer A laminate of known materials such as phthalocyanine derivatives such as polyfluorene and copper phthalocyanine, arylamine derivatives having a polymerizable group, and Ir complexes may be used.

The bank 23 having a curvature has an arc shape in FIG. 1, but the shape of the bank according to the present invention is not limited to this, and has a curvature at least partially (in other words, a curved surface at least partially). The bank is not particularly limited.
The width of the bank 23 is generally 10 to 50 μm, preferably 20 to 50 μm, more preferably 20 to 40 μm. The height of the bank 23 is generally 1 to 10 μm, preferably 2 to 8 μm, more preferably 2 to 5 μm.
Examples of the shape of the bank 23 include an arc shape, a triangular shape, and a trapezoidal shape, but the bank 23 preferably does not have a flat portion. Since the bank 23 does not have a flat portion, the droplets attached to the bank are less likely to stay on the bank wall surface, and can move to the pixel region more efficiently. The bank 23 is more preferably arcuate or triangular, and more preferably arcuate.

The material of the bank 23 is not particularly limited as long as the relationship of the contact angle with respect to the pure water is satisfied, and examples thereof include polyimide, novolac resin, epoxy resin, acrylic resin, and the like, and is preferably polyimide from the viewpoint of hydrophobicity. . The bank may be subjected to water repellent treatment as necessary. As a specific method, CF ₄ may be deposited in a bank by CVD, or a silane coupling agent having a long-chain fluoroalkyl group or a fluoropolymer may be mixed in the bank.
As a method for forming a bank, (1) a method using patterning and development by UV light using a photosensitive resist or polyimide, and (2) patterning by UV light by coating a resist on polyimide capable of alkali development, Examples include a method using development, and (3) a method using patterning by screen printing using an epoxy resin and UV crosslinking.

The pixel area 24 is an area surrounded by the bank 23, and a coating liquid containing the liquid organic substance or the liquid crystalline organic substance is applied to the area. If necessary, a layer may be formed by applying a coating solution containing other organic substances to the pixel region 24 before and after the coating solution is applied to the pixel region 24.
The width of the pixel region 24 is generally 50 to 500 μm, preferably 80 to 300 μm.
In the present invention, the shape of the pixel region is not particularly limited as long as the pixel region has the above-described size, and is quadrilateral (including rectangle, square, rhombus), polygon (pentagon, hexagon, etc.). Any shape such as a circular shape (including a perfect circle and an ellipse), a cross shape, and other similar shapes can be used, but in the coating method using the ink jet method, the droplets are easily wetted. Therefore, in the case of a shape having an edge portion (for example, a corner portion or a vertex portion in a quadrangle), it is preferable that the edge portion is a curved surface. By doing in this way, when the coating liquid is filled in the pixel region, the edge portion can be easily wetted.
The pixel region is provided with a pixel electrode by applying a coating liquid. The organic substance contained in the coating liquid is an organic semiconductor material for forming a thin film light emitting element. In this case, for example, the pixel electrode is an ITO electrode film.

[2] Coating liquid The coating liquid of the present invention contains at least a liquid organic substance or an organic substance having liquid crystallinity. The liquid organic substance and the organic substance having liquid crystallinity are preferably organic semiconductor materials, and more preferably light emitting layer forming materials. This is because it is necessary to divide the pixels of the light emitting layer. Here, the organic semiconductor material and the light emitting layer forming material do not include a solvent (coating solvent) for dissolving or compatibilizing a liquid organic material or a liquid crystal organic material.
Below, the organic substance which has liquid crystallinity contained in the coating liquid of this invention, a liquid organic substance, and the solvent (coating solvent) which melt | dissolves or is compatible with these organic substances are demonstrated.

[2-1] Organic substance having liquid crystallinity As the organic substance having liquid crystallinity, a known organic substance having liquid crystallinity can be used, but an organic semiconductor material having liquid crystallinity is preferable, and liquid crystallinity is more preferable. A light emitting layer forming material, more preferably a host material having liquid crystallinity or a light emitting material having liquid crystallinity.
Examples of the host material having liquid crystallinity include triphenylene derivatives, pyrene derivatives, and perylene derivatives having liquid crystallinity. From the viewpoint of charge mobility, triphenylene derivatives having liquid crystallinity are preferable.

[Triphenylene derivative having liquid crystallinity]
As the triphenylene derivative having liquid crystallinity, a conventionally known discotic liquid crystalline triphenylene derivative can be used, and examples thereof include a triphenylene derivative represented by the following general formula (TI). The triphenylene derivative having liquid crystallinity, it is preferable that the triphenylene derivative expressing a discotic nematic phase having a good monodomain property (N _D phase). When the coating solution of the present invention is a coating solution for forming a light emitting layer, the triphenylene derivative having liquid crystallinity functions as a host material in the light emitting layer formed from the coating solution. A triphenylene derivative having liquid crystallinity is hardly crystallized even when driven at high luminance. In addition, the triphenylene derivative having liquid crystallinity is oriented and has higher solubility in an organic solvent than a triphenylene derivative not exhibiting liquid crystallinity.

In the above general formula (T-I), R _T represents R _T ¹ —, R _T ¹ —O—, R _T ¹ —CO—O—, or R _T ¹ —O—CO—. Although all the compounds having these groups are not discotic liquid crystalline, an appropriate group that exhibits discotic liquid crystallinity can be selected and used based on known techniques. Examples of R _T ¹ include an alkyl group, an alkyl group in which a ring such as a phenylene group or a cyclohexylene group is combined, an oxygen group in which an oxygen atom is arranged between carbon and carbon of the alkyl group, and the like.

As R _T , specifically, R _T ² —, R _T ² —O—, R _T ² —O—R _T ³ —, R _T ² —O—R _T ³ —O—, R _T ² — O—Ph—COO—, R _T ² — (O—R _T ³ ) _nT —O—Ph—COO—, R _T ² —O—Ph—CH═CH—COO—, CH ₂ = CH—COO—R _T ³ —O—Ph—COO— may be mentioned. Here, R _T ² represents an alkyl group which may have a polymerizable group, R _T ³ represents an alkylene group, Ph represents a phenylene group which may have a substituent, n _T , Is a repeating number _of- (O-R _T ³ )-and represents an integer of 1 or more.

R _T ² represents an alkyl group which may have a polymerizable group, when having a polymerizable group, it is preferable from the viewpoint of the expression of the N _D phase having a polymerizable group at the top end of the alkyl group. Examples of the polymerizable group include an acrylic acid ester group, a methacrylic acid ester group, a crotonic acid ester group, and an epoxy group. From the viewpoint of polymerization speed, ease of synthesis, and cost, an acrylic acid ester group and a methacrylic acid ester group. Groups are preferred, and acrylate groups are more preferred.
Carbon number of the alkyl group part in the alkyl group which may have a polymerizable group represented by R _T ² is preferably in the range of 1-20, more preferably in the range of 1-15, and further Preferably it is the range of 3-10.
The number of carbon atoms of the alkylene group represented by R _T ³ is preferably in the range of 1 to 20, more preferably in the range of 1 to 15, and still more preferably in the range of 3 to 10.
Ph represents a phenylene group which may have a substituent group, includes as the substituent also be a halogen atom such as fluorine atom, an alkyl group, an alkoxy group, and the expression of the N _D phase From the viewpoint, an alkyl group is preferable. The number of carbon atoms of the alkyl group or alkoxy group as a substituent is preferably in the range of 1 to 20, more preferably in the range of 1 to 10, and still more preferably in the range of 1 to 6.
n _{T ^{is, - (O-R T 3}} ) - number of repetitions of the represents an integer of 1 or more. n _T is preferably an integer of 1 to 10, more preferably an integer from 1 to 6, more preferably an integer of 1 to 3.

The R _T, in terms of expression of the _{N D ^{phase, R T 2 -O-Ph-}} COO-, R T 2 - (O-R T 3) nT -O-Ph-COO-, R T 2 - O-Ph-CH = CH- COO- is ^{_{preferred, R T 2 -O-Ph-}} COO- are more preferred.

Triphenylene derivative represented by the above general formula (T-I) in that they express the N _D phase, it is preferably a triphenylene derivative represented by the following general formula (T-II).

In the above general formula (T-II), R _T ′ is R _T ² —O—Ph—CO—, R _T ² — (O—R _T ³ ) _nT —O—Ph—CO—, or R _T ^2. —O—Ph—CH═CH—CO— is represented. The definitions of R _T ² , Ph, R _T ³ , and n _T are synonymous with R _T ² , Ph, R _T ³ , and n _{T in} the general formula (TI). Specific examples and preferred ranges of R _T ² , Ph, R _T ³ , and n _{T in} the general formula (T-II) are the same as those in the general formula (T-I).

R _T ', since the expression of _{N D} phase is good, the following general formula (T-II-1) ~ It is more preferably represented by any one of (T-II-5).

In the general formulas (T-II-1) to (T-II-5), n and n ′ each independently represent an integer of 1 or more.
X _T represents a polymerizable group.

n represents an integer of 1 or more. n is preferably an integer of 1 to 20, more preferably an integer of 1 to 15, and still more preferably an integer of 3 to 10.
n ′ represents an integer of 1 or more. n ′ is preferably an integer of 1 to 10, more preferably an integer of 1 to 6, and still more preferably an integer of 1 to 3.
X _T represents a polymerizable group, and specific examples and preferred ranges are specific examples of the general formula (T-I) in which may have an alkyl group represented by R _T ² polymerizable groups and This is the same as the preferred range.

  Among the triphenylene derivatives having liquid crystallinity in the present invention, those that cause the liquid crystal phase to be expressed in the range of 20 ° C to 300 ° C are preferable. More preferably, it is 40 degreeC-280 degreeC, More preferably, it is 60 degreeC-250 degreeC. Here, the expression of the liquid crystal phase at 20 ° C. to 300 ° C. also means that the liquid crystal temperature range extends over 20 ° C. (for example, 10 ° C. to 22 ° C.) or 300 ° C. (for example, 298 ° C. to 310 ° C.). Including. The same applies to 40 ° C to 280 ° C and 60 ° C to 250 ° C.

  The content of the triphenylene derivative having liquid crystallinity in the coating solution of the present invention is preferably 15 to 97% by mass, more preferably 30 to 95% by mass based on the total solid content in the coating solution. More preferably, it is 50 to 90% by mass.

  Specific examples of the triphenylene derivative having liquid crystallinity are shown below, but the present invention is not limited thereto.

  Examples of the light emitting material having liquid crystallinity include a pyrene derivative and a perylene derivative having liquid crystallinity. From the viewpoint of color purity, a pyrene derivative having liquid crystallinity is preferable.

[Pyrene derivatives having liquid crystallinity]
Examples of the pyrene derivative having liquid crystallinity include a pyrene derivative represented by the following general formula (PI).

In the general formula (P-I), R _P means R _P ¹ — or R _P ¹ —CO—. p is the number of substituents and represents an integer of 1 to 5. Although all the compounds having these groups are not liquid crystalline, an appropriate group having liquid crystallinity can be selected and used based on known techniques. Examples of _RP ¹ include an alkyl group, an alkyl group in which a ring such as a phenylene group or a cyclohexylene group is combined, an oxygen group in which an oxygen atom is disposed between carbon and carbon of the alkyl group, and the like.

The R _{P, ^{specifically, R P 2 -, R P}} 2 -O-R P 3 -, R P 2 -O-Ph-CO-, R P 2 - (O-R P 3) nP - ^{_{O-Ph-CO-, R P}} 2 -O-Ph-CH = CH-CO-, CH 2 = CH-COO-R P 3 -O-Ph-CO- and the like. Here, R _P ² represents an alkyl group, R _P ³ represents an alkylene group, Ph represents a phenylene group which may have a substituent, and n _P represents-(O-R _P ³ )-. And represents an integer of 1 or more.

The number of carbon atoms of the alkyl group represented by R _P ² is preferably in the range of 1-20, more preferably in the range of 1-15, and even more preferably in the range of 3-10. The alkyl group represented by R _P ² may be linear or branched, but is preferably linear in terms of liquid crystallinity.
The number of carbon atoms of the alkylene group represented by R _P ³ is preferably in the range of 1-20, more preferably in the range of 1-15, and even more preferably in the range of 3-10.
Ph represents a phenylene group which may have a substituent group, includes as the substituent also be a halogen atom such as fluorine atom, an alkyl group, an alkoxy group, and the expression of the N _D phase From the viewpoint, an alkyl group is preferable. The number of carbon atoms of the alkyl group or alkoxy group as a substituent is preferably in the range of 1 to 20, more preferably in the range of 1 to 10, and still more preferably in the range of 1 to 6.
n _{P ^{is, - (O-R P 3}} ) - number of repetitions of the represents an integer of 1 or more. n _P is preferably an integer of from 1 to 10, more preferably an integer from 1 to 6, more preferably an integer of 1 to 3.

The R _P, in terms of _{solubility, R} ^{P 2} - is preferred.
p is the number of substituents, preferably an integer of 1 to 3, more preferably an integer of 1 or 2. The pyrene derivative represented by the general formula (PI) preferably has a substituent at least at the 4-position of the benzene ring from the viewpoint of imparting liquid crystallinity and solubility.

  The pyrene derivative represented by the general formula (P-I) is preferably a pyrene derivative represented by the following general formula (P-II) from the viewpoint of high solubility.

In the general formula _{(P-II), R} P has the same meaning as _{R P} in the general formula (P-I).

Specific examples and preferred ranges of _{R P} in the general formula (P-II) are the same as those in general formula (P-I).

  Specific examples of the pyrene derivative having liquid crystallinity are shown below, but the present invention is not limited thereto.

The content of the pyrene derivative having liquid crystallinity in the coating liquid of the present invention is preferably 0.5 to 30% by mass, and preferably 1 to 20% by mass based on the total solid content in the coating liquid. More preferably, it is still more preferable that it is 1.5-10 mass%.
[2-2] Liquid Organic Substance The liquid organic substance used in the present invention is not only an organic substance that is liquid at 25 ° C. (room temperature) (hereinafter also referred to as “liquid organic substance at room temperature”), but also the application of the present invention. Also included are organic substances that melt by heating at the time of drying after application of the liquid to become liquids (hereinafter also referred to as “organic substances that melt by heating”). These liquid organic substances are preferably liquid organic semiconductor materials, more preferably liquid light-emitting layer forming materials, and still more preferably liquid host materials.
Each will be described below.

[Organic liquid at room temperature]
Examples of organic substances that are liquid at room temperature include 9- (2-ethylhexyl) carbazole described in Applied Physics Letters 95,053304 (2009).

  The concentration of the organic substance that is liquid at room temperature in the coating solution of the present invention is preferably 15 to 97% by mass, more preferably 30 to 95% by mass, and still more preferably 50 to 90% by mass.

[Organic substances that melt by heating]
The organic substance that melts by heating is an organic substance that melts at a temperature equal to or lower than the heating temperature at the time of drying after application of the coating liquid to become a liquid. The organic substance that melts by heating is preferably an organic substance having a melting point in the range of 80 ° C to 220 ° C, more preferably an organic substance having a melting point in the range of 120 ° C to 220 ° C, and more preferably 120 ° C to 180 ° C. It is an organic substance having a melting point in the range of ° C.

  Examples of the organic substance having a melting point in the range of 80 ° C. to 220 ° C. include carbazole derivatives having an asymmetric structure, compounds having the following structural formula described in JP-A-2007-269772 (melting temperature: 170 ° C.), N-carbazole derivatives, and the like. In view of device durability, an asymmetric carbazole derivative or N-carbazole derivative is preferable. As the carbazole derivative having an asymmetric structure, a carbazole derivative having an asymmetric structure represented by the following general formula (Acz) is preferable from the viewpoint of a low melting point.

In the general formula (ACz), R _As represents a tert-butyl group, a tert-amyl group, or a trimethylsilyl group.

In the compound represented by the general formula (ACz), when R _As is a tert-butyl group, the melting point is 125 ° C., and when the tert-amyl group is used, the melting point is 128 ° C. Is 135 ° C.

  As the N-carbazole derivative, an N-carbazole derivative represented by the following general formula (Ncz) is preferable from the viewpoint of a low melting point.

In the general formula (NCz), _{R N} represents an alkyl group or an aryl group.

The number of carbon atoms in the alkyl group represented by R _N is preferably in the range of 1 to 20, more preferably in the range of 1 to 15, more preferably from 1 to 10, even more preferably methyl Group, an ethyl group. Alkyl group represented by R _N may be an even branched linear, but it is preferable from the viewpoint of the liquid crystal is linear.
Aryl groups the number of carbon atoms represented by R _N is preferably in the range of 6 to 20, more preferably in the range of 6-12, more preferably a phenyl group.

  Specific examples of the compound represented by the general formula (NCz) include 9-ethylcarbazole (melting point 68 ° C.), 9-methylcarbazole (melting point 89 ° C.), 9-phenylcarbazole (melting point 88 ° C.) and the like. .

  The content of the organic substance melted by heating in the coating solution of the present invention at room temperature is preferably 15 to 97% by mass, and preferably 30 to 95% by mass based on the total solid content in the coating solution. More preferably, it is further more preferable that it is 50-90 mass%.

The coating liquid of the present invention may further contain an organic substance other than the liquid organic substance or the organic substance having liquid crystallinity as long as the effects of the present invention are not impaired. Examples of such an organic substance include a light emitting material, a hole transport material, and an electron transport material.
When the coating liquid of the present invention further contains an organic substance other than the above liquid organic substance or liquid crystalline organic substance, the content of these organic substances in the coating liquid of the present invention is based on the total solid content in the coating liquid. The content is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, and still more preferably 1.5 to 10% by mass.

[2-3] Solvent In the coating liquid of the present invention, as a solvent (coating solvent) that dissolves or is compatible with the above-described liquid organic substance or liquid crystalline organic substance, a conventionally known solvent is appropriately used depending on the organic substance. Is possible.
Examples of the coating solvent include known organic solvents such as aromatic hydrocarbon solvents, alcohol solvents, ketone solvents, aliphatic hydrocarbon solvents, amide solvents, and the like.

  Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, trimethylbenzene, tetramethylbenzene, cumeneethylbenzene, methylpropylbenzene, methylisopropylbenzene, and the like, and toluene, xylene, cumene, and trimethylbenzene are more preferable. preferable.

Examples of the alcohol solvent include methanol, ethanol, butanol, benzyl alcohol, cyclohexanol, and the like, butanol, benzyl alcohol, and cyclohexanol are more preferable. The relative dielectric constant of the alcohol solvent is usually 10-40.
Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, 2-butanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, and phenylacetone. , Methyl ethyl ketone, methyl isobutyl ketone, acetyl acetone, acetonyl acetone, ionone, diacetonyl alcohol, acetyl carbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, etc., 2-butanone, methyl isobutyl ketone, propylene carbonate preferable.
Examples of the aliphatic hydrocarbon solvent include pentane, hexane, octane, decane and the like, and octane and decane are preferable.
Examples of amide solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, 1,3-dimethyl-2-imidazolidinone and the like. N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone are preferred.
In the present invention, the above solvents may be used alone or in combination of two or more.

In the coating liquid of the present invention, it is preferable that the liquid organic substance or the organic substance having liquid crystallinity is a light emitting layer forming material (that is, the coating liquid of the present invention is a light emitting layer forming coating liquid). It is more preferable to apply the light emitting layer forming coating solution on the hole injection layer or the hole transport layer formed in the region.
FIG. 2 shows a state in which the light emitting layer 25 is formed on the hole injection layer or hole transport layer 26 formed in the pixel region 24 by the coating liquid of the present invention.
The light emitting layer formed from the light emitting layer forming coating solution is preferably used in a film thickness of 5 to 100 nm, and more preferably in a film thickness of 30 to 50 nm. Such a film thickness can be obtained by setting the solid content concentration in the coating solution to an appropriate range to give an appropriate viscosity and improving the coating property and film forming property.
The total solid concentration in the coating liquid of the present invention is generally 0.05 to 30% by mass, more preferably 0.1 to 20% by mass, and still more preferably 0.1 to 10% by mass.
The viscosity in the coating liquid of the present invention is generally 1 to 30 mPa · s, more preferably 1.5 to 20 mPa · s, and still more preferably 1.5 to 15 mPa · s from the viewpoint of ejection stability. .

  The coating solution of the present invention is used by dissolving the above components in a predetermined organic solvent, filtering the solution, and applying the solution on a predetermined support or layer as follows. The pore size of the filter used for filter filtration is 2.0 μm or less, more preferably 0.5 μm or less, and still more preferably 0.3 μm or less made of polytetrafluoroethylene, polyethylene, or nylon.

The coating method of the coating liquid of the present invention is not particularly limited, and can be formed by any conventionally known coating method. Examples thereof include an ink jet method, a spray coating method, a spin coating method, a bar coating method, a transfer method, and a printing method.
The heating temperature and time after coating are not particularly limited as long as the coating solution is dried, but the heating temperature is generally 100 ° C to 200 ° C, preferably 120 ° C to 160 ° C. The heating time is generally 1 minute to 120 minutes, preferably 1 minute to 60 minutes, more preferably 1 minute to 25 minutes.

[3] Contact angle with respect to pure water In the method for producing an organic electroluminescence display device of the present invention, the contact angle θ1 with respect to pure water of the coating surface on which the coating liquid according to the present invention is coated, the film formed from the coating liquid The contact angle θ2 with respect to pure water and the contact angle θ3 with respect to the pure water of the bank satisfy the relationship of the following formulas (1) and (2).
| Θ2-θ1 | <| θ3-θ2 | Formula (1)
θ2 <θ3 Formula (2)
Formula (1) indicates that the absolute value of the difference between the contact angle θ1 with respect to pure water of the coating surface on which the coating solution is applied and the contact angle θ2 with respect to pure water of the film formed from the coating solution is It means that the absolute value of the difference between the contact angle θ2 of the film formed from the liquid with respect to pure water and the contact angle θ3 with respect to the pure water of the bank is smaller.
The absolute value (| θ2-θ1 |) of the difference between θ1 and θ2 is preferably 0 to 10 degrees, and more preferably 0 to 5 degrees. The absolute value (| θ3-θ2 |) of the difference between θ2 and θ3 is preferably larger than 10 degrees. The absolute value of the difference between θ2 and θ3 is generally 100 degrees or less, preferably 80 degrees or less.
The θ1, θ2, and θ3 preferably satisfy the following relationship.
Contact angle θ1 with respect to pure water of a coating surface on which the coating solution is applied ≦ contact angle θ2 with respect to pure water of a film formed from the coating solution <contact angle θ3 with respect to pure water of the bank

By using a contact angle meter (such as a fully automatic contact angle meter DM-301 manufactured by Kyowa Interface Chemical Co., Ltd.), the contact angle can be measured. In addition, the contact angle with respect to the pure water of the film | membrane formed from the said coating liquid can be calculated | required by forming a thin film from the said coating liquid and measuring at the temperature which does not generate | occur | produce fluidity | liquidity. The coating surface to which the coating liquid according to the present invention is applied is a substrate surface when a layer is not formed in advance in the pixel region, and when a layer is formed in the pixel region in advance, This is the surface of the layer.
The contact angle θ1 of the coated surface with respect to pure water is preferably 10 to 90 degrees, more preferably 20 to 80 degrees, and still more preferably 20 to 70 degrees.
The contact angle θ2 of the film formed from the coating solution with respect to pure water is preferably 30 to 90 degrees, more preferably 30 to 80 degrees, and still more preferably 40 to 80 degrees.
The contact angle θ3 with respect to the pure water of the bank is preferably 80 to 110 degrees, and more preferably 90 to 110 degrees.
The contact angle of the substrate surface with pure water or the contact angle of the bank with pure water can be set to the above range by subjecting the substrate surface and the bank to surface treatment by the method described in Japanese Patent No. 3328297, for example.

When the coating liquid of the present invention is a light emitting layer forming coating liquid, the light emitting layer forming coating liquid is preferably applied onto the hole injection layer or the hole transport layer formed in the pixel region. In this case, the coating surface on which the coating solution is applied is the surface of the hole injection layer or the hole transport layer, the contact angle θ4 of the hole injection layer or the hole transport layer with respect to pure water, and the θ2 and θ3. Satisfies the relationship of the following formula (3).
| Θ2-θ4 | <| θ3-θ2 | Equation (3)
Note that the absolute value of the difference between the contact angle θ4 with respect to pure water of the hole injection layer or the hole transport layer and the contact angle θ2 with respect to pure water of the film formed from the coating solution is expressed by the equation (3). This means that the absolute value of the difference between the contact angle θ2 of the film formed from the coating solution with respect to pure water and the contact angle θ3 with respect to the pure water of the bank is smaller.
The absolute value (| θ2-θ4 |) of the difference between θ4 and θ2 is preferably 0 to 10 degrees, and more preferably 0 to 5 degrees. The absolute value (| θ3-θ2 |) of the difference between θ2 and θ3 is the same as described above.
It is preferable that θ4, θ2, and θ3 satisfy the following relationship from the viewpoints of film forming property and prevention of adhesion of the coating liquid to the bank.
Contact angle θ4 with respect to pure water of the hole injection layer or hole transport layer ≦ contact angle θ2 with respect to pure water of a film formed from the coating liquid <contact angle θ3 with respect to pure water of the bank

  At this time, the contact angle θ4 of the hole injection layer or the hole transport layer with respect to pure water is preferably 10 to 90 degrees, and more preferably 10 to 80 degrees.

[4] Configuration of Organic Electroluminescent Device The present invention also relates to an organic electroluminescent device manufactured by the method for manufacturing an organic electroluminescent device.
The configuration of the organic electroluminescent device in the present invention will be described in detail.

  The specific configuration of the display device and the method for manufacturing the display device are described in detail in, for example, the third embodiment described in Japanese Patent No. 3328297, and the matters described in this publication can be applied to the present invention. it can.

Hereinafter, a specific configuration of the organic electroluminescent device will be described in detail.
The organic electroluminescent element has a pair of electrodes, that is, an anode and a cathode, and a light emitting layer between both electrodes. Examples of the functional layer other than the light emitting layer that can be disposed between both electrodes include a hole transport layer, an electron transport layer, a hole block layer, an electron block layer, a hole injection layer, and an electron injection layer.

The organic electroluminescent element preferably has a hole transport layer between the anode and the light emitting layer, and preferably has an electron transport layer between the cathode and the light emitting layer. Furthermore, a hole injection layer may be provided between the hole transport layer and the anode, or an electron injection layer may be provided between the electron transport layer and the cathode.
In addition, a hole transporting intermediate layer (electron blocking layer) may be provided between the light emitting layer and the hole transporting layer, and an electron transporting intermediate layer (hole blocking layer) is provided between the light emitting layer and the electron transporting layer. Layer) may be provided. Each functional layer may be divided into a plurality of secondary layers.

  In view of the properties of the light-emitting element, at least one of the anode and the cathode is preferably transparent or translucent.

<Structure of organic layer>
There is no restriction | limiting in particular as a layer structure of an organic layer, Although it can select suitably according to the use and objective of an organic electroluminescent element, It is preferable to form on the said transparent electrode or the said back electrode. In this case, the organic layer is formed on the front surface or one surface of the transparent electrode or the back electrode.
There is no restriction | limiting in particular about the shape of a organic layer, a magnitude | size, thickness, etc., According to the objective, it can select suitably.

Specific examples of the layer configuration include the following, but the present invention is not limited to these configurations.
Anode / hole transport layer / light emitting layer / electron transport layer / cathode,
Anode / hole transport layer / light emitting layer / block layer / electron transport layer / cathode,
Anode / hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer / cathode,
Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode.
Anode / hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer / cathode,
Anode / hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer / cathode.
Anode / hole injection layer / hole transport layer / exciton block layer / light emitting layer / electron transport layer / electron injection layer / cathode.
The element configuration, the substrate, the cathode, and the anode of the organic electroluminescence element are described in detail in, for example, Japanese Patent Application Laid-Open No. 2008-270736, and the matters described in the publication can be applied to the present invention.

<Board>
The substrate used in the present invention is preferably a substrate that does not scatter or attenuate light emitted from the organic layer. In the case of an organic material, it is preferable that it is excellent in heat resistance, dimensional stability, solvent resistance, electrical insulation, and workability.

<Anode>
The anode usually only needs to have a function as an electrode for supplying holes to the organic layer, and there is no particular limitation on the shape, structure, size, etc., depending on the use and purpose of the light-emitting element, It can select suitably from well-known electrode materials. As described above, the anode is usually provided as a transparent anode.

<Cathode>
The cathode usually has a function as an electrode for injecting electrons into the organic layer, and there is no particular limitation on the shape, structure, size, etc., and it is known depending on the use and purpose of the light-emitting element. The electrode material can be selected as appropriate.

  Regarding the substrate, anode, and cathode, the matters described in paragraphs [0070] to [0089] of JP-A-2008-270736 can be applied to the present invention.

<Organic layer>
The organic layer in the present invention will be described.

[Formation of organic layer]
In the organic electroluminescent device of the present invention, each organic layer is formed by a solution coating process such as a dry film forming method such as an evaporation method or a sputtering method, a transfer method, a printing method, a spin coating method, a bar coating method, an ink jet method, or a spray method. Any of these can be suitably formed.

  In addition to the layer formed from the coating solution of the present invention, any one of the organic layers is preferably formed by a wet method, and the hole injection layer or the hole transport layer is more preferably formed by a wet method. . The other layers can be formed by appropriately selecting a dry method or a wet method. When the wet method is used, the organic layer can be easily increased in area, and a light-emitting element having high luminance and excellent light emission efficiency can be obtained efficiently at low cost, which is preferable. Vapor deposition, sputtering, etc. can be used as dry methods, and dipping, spin coating, dip coating, casting, die coating, roll coating, bar coating, gravure coating, and spray coating as wet methods. An ink jet method or the like can be used. These film forming methods can be appropriately selected according to the material of the organic layer. When the film is formed by a wet method, it may be dried after the film is formed. Drying is performed by selecting conditions such as temperature and pressure so that the coating layer is not damaged.

The coating solution used in the wet film-forming method (coating process) usually comprises an organic layer material and a solvent for dissolving or dispersing it. A solvent is not specifically limited, What is necessary is just to select according to the material used for an organic layer. Specific examples of the solvent include halogen solvents (chloroform, carbon tetrachloride, dichloromethane, 1,2-dichloroethane, chlorobenzene, etc.), ketone solvents (acetone, methyl ethyl ketone, diethyl ketone, n-propyl methyl ketone, 2-butanone, Cyclohexanone, etc.), aromatic solvents (benzene, toluene, xylene, etc.), ester solvents (ethyl acetate, n-propyl acetate, n-butyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, diethyl carbonate, etc.) , Ether solvents (tetrahydrofuran, dioxane, etc.), amide solvents (dimethylformamide, dimethylacetamide, etc.), dimethyl sulfoxide, alcohol solvents (methanol, propanol, butanol, etc.), water and the like.
The solid content with respect to the solvent in the coating solution is not particularly limited, and the viscosity of the coating solution can be arbitrarily selected according to the film forming method.

[Light emitting layer]
In the organic electroluminescent device of the present invention, the light emitting layer contains a light emitting material, and the light emitting material preferably contains a phosphorescent compound. The phosphorescent compound is not particularly limited as long as it is a compound that can emit light from triplet excitons. As the phosphorescent compound, an orthometalated complex or a porphyrin complex is preferably used, and an orthometalated complex is more preferably used. Of the porphyrin complexes, a porphyrin platinum complex is preferred. The phosphorescent compounds may be used alone or in combination of two or more.

  The orthometalated complex referred to in the present invention is a material described in Akio Yamamoto, “Organic Metal Chemistry Fundamentals and Applications,” pages 150 and 232, Houhuabosha (1982), H.C. Yersin's “Photochemistry and Photophysics of Coordination Compounds”, pages 71-77 and pages 135-146, Springer-Verlag (1987), etc. The ligand forming the ortho-metalated complex is not particularly limited, but a 2-phenylpyridine derivative, a 7,8-benzoquinoline derivative, a 2- (2-thienyl) pyridine derivative, a 2- (1-naphthyl) pyridine derivative or A 2-phenylquinoline derivative is preferred. These derivatives may have a substituent. Moreover, you may have another ligand other than these essential ligands for ortho metalation complex formation. As the central metal forming the orthometalated complex, any transition metal can be used. In the present invention, rhodium, platinum, gold, iridium, ruthenium, palladium and the like can be preferably used. Of these, iridium is particularly preferable. An organic layer containing such an orthometalated complex is excellent in light emission luminance and light emission efficiency. Specific examples of the orthometalated complex are also described in paragraphs 0152 to 0180 of Japanese Patent Application No. 2000-254171.

  The orthometalated complex used in the present invention can be obtained from Inorg. Chem. 30, 1685, 1991, Inorg. Chem. 27, 3464, 1988, Inorg. Chem. 33, 545, 1994, Inorg. Chim. Acta, 181, 245, 1991; Organomet. Chem. , 335, 293, 1987; Am. Chem. Soc. , 107, 1431, 1985 and the like.

  Although content in particular of the phosphorescence-emitting compound in a light emitting layer is not restrict | limited, For example, it is 0.1-70 mass%, and it is preferable that it is 1-20 mass%. If the content of the phosphorescent compound is less than 0.1% by mass or exceeds 70% by mass, the effect may not be sufficiently exhibited.

  In the present invention, the light emitting layer may contain a host compound as necessary.

  The host compound is a compound that causes energy transfer from the excited state to the phosphorescent compound, and as a result, causes the phosphorescent compound to emit light. Specific examples include carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrylanthracene derivatives. , Fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrylamine compounds, aromatic dimethylidene compounds, porphyrin compounds, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiopyran dioxide oxide Derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, and heterocyclic tetra Rubonic acid anhydride, phthalocyanine derivative, metal complex of 8-quinolinol derivative, metal phthalocyanine, metal complex having benzoxazole or benzothiazole as a ligand, polysilane compound, poly (N-vinylcarbazole) derivative, aniline copolymer , Conductive polymers such as thiophene oligomers and polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, and the like. A host compound may be used individually by 1 type, or may use 2 or more types together.

  The thickness of the light emitting layer is preferably 10 to 200 nm, and more preferably 20 to 80 nm. When the thickness exceeds 200 nm, the driving voltage may increase. When the thickness is less than 10 nm, the light emitting element may be short-circuited.

(Hole injection layer, hole transport layer)
The organic electroluminescent element of the present invention preferably has a hole injection layer and a hole transport layer. The hole injection layer and the hole transport layer are layers having a function of receiving holes from the anode or the anode side and transporting them to the cathode side.
The hole injection layer and the hole transport layer are described in detail, for example, in JP-A-2008-270736 and JP-A-2007-266458, and the matters described in these publications can be applied to the present invention.

(Electron injection layer, electron transport layer)
The organic electroluminescent element of the present invention may have an electron injection layer and an electron transport layer. The electron injection layer and the electron transport layer are layers having a function of receiving electrons from the cathode or the cathode side and transporting them to the anode side. The electron injection material and the electron transport material used for these layers may be a low molecular compound or a high molecular compound.
The electron injection layer and the electron transport layer are described in detail, for example, in JP-A-2008-270736 and JP-A-2007-266458, and the matters described in these publications can be applied to the present invention.

(Hole blocking layer)
The hole blocking layer is a layer having a function of preventing holes transported from the anode side to the light emitting layer from passing through to the cathode side. In the present invention, a hole blocking layer can be provided as an organic layer adjacent to the light emitting layer on the cathode side.
As an example of the organic compound constituting the hole blocking layer, aluminum (III) bis (2-methyl-8-quinolinato) 4-phenylphenolate (Aluminum (III) bis (2-methyl-8-quinolinato) 4- aluminum complexes such as phenylphenolate (abbreviated as BAlq), triazole derivatives, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (2,9-Dimethyl-4,7-diphenyl-1,10-) phenanthroline derivatives such as phenanthroline (abbreviated as BCP), triphenylene derivatives, carbazole derivatives, and the like.
The thickness of the hole blocking layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and still more preferably 10 nm to 100 nm.
The hole blocking layer may have a single layer structure made of one or more of the materials described above, or may have a multilayer structure made of a plurality of layers having the same composition or different compositions.

(Electronic block layer)
The electron blocking layer is a layer having a function of preventing electrons transported from the cathode side to the light emitting layer from passing through to the anode side. In the present invention, an electron blocking layer can be provided as an organic layer adjacent to the light emitting layer on the anode side.
As an example of the organic compound constituting the electron blocking layer, for example, those mentioned as the hole transport material described above can be applied.
The thickness of the electron blocking layer is preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm, and even more preferably 10 nm to 100 nm.
The electron blocking layer may have a single layer structure composed of one or more of the above-described materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.

(Description of exciton block layer)
The exciton blocking layer is a layer formed at one or both of the interface between the light emitting layer and the hole transport layer, or the interface between the light emitting layer and the electron transport layer, and the excitons generated in the light emitting layer are holes. It is a layer that diffuses into the transport layer and the electron transport layer and prevents deactivation without emitting light. The exciton blocking layer is preferably made of a carbazole derivative.

[Other organic layers]
The organic electroluminescent device of the present invention has a protective layer described in JP-A-7-85974, 7-192866, 8-22891, 10-275682, 10-106746, etc. Also good. The protective layer is formed on the uppermost surface of the light emitting element. Here, when the base material, the transparent electrode, the organic layer, and the back electrode are laminated in this order, the top surface refers to the outer surface of the back electrode, and the base material, the back electrode, the organic layer, and the transparent electrode are laminated in this order. In some cases, it refers to the outer surface of the transparent electrode. The shape, size, thickness and the like of the protective layer are not particularly limited. The material for forming the protective layer is not particularly limited as long as it has a function of suppressing intrusion or permeation of a light-emitting element such as moisture or oxygen into the element. Silicon, germanium oxide, germanium dioxide or the like can be used.

  The method for forming the protective layer is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular sensing epitaxy, cluster ion beam, ion plating, plasma polymerization, plasma CVD, laser CVD Thermal CVD method, coating method, etc. can be applied.

[Sealing]
The organic electroluminescent element is preferably provided with a sealing layer for preventing moisture and oxygen from entering. As a material for forming the sealing layer, a copolymer of tetrafluoroethylene and at least one comonomer, a fluorinated copolymer having a cyclic structure in the copolymer main chain, polyethylene, polypropylene, polymethyl methacrylate, polyimide, Polyurea, polytetrafluoroethylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, chlorotrifluoroethylene or a copolymer of dichlorodifluoroethylene and another comonomer, a water-absorbing substance having a water absorption of 1% or more, a water absorption of 0. 1% or less moisture-proof material, metal (In, Sn, Pb, Au, Cu, Ag, Al, Tl, Ni, etc.), metal oxide (MgO, SiO, SiO ₂ , Al ₂ O ₃ , GeO, NiO, _{CaO, BaO, Fe 2 O 3} , Y 2 O 3, TiO 2 , etc.), metal fluorides (M _{F 2, LiF, AlF 3,} CaF 2 , etc.), liquid fluorinated carbon (perfluoroalkane, perfluoro amines, perfluoroether, etc.), the liquid fluorinated carbon as dispersed adsorbent moisture or oxygen, etc. Can be used.

  The organic electroluminescence device of the present invention emits light by applying a direct current (which may include an alternating current component as necessary) voltage (usually 2 to 15 volts) or a direct current between the anode and the cathode. Obtainable.

  The driving method of the organic electroluminescence device of the present invention is described in JP-A-2-148687, JP-A-6-301355, JP-A-5-29080, JP-A-7-134558, JP-A-8-234658, and JP-A-8-2441047. The driving methods described in each publication, Japanese Patent No. 2784615, US Pat. Nos. 5,828,429, 6023308, and the like can be applied.

<Top emission type organic EL display device>
For example, as shown in FIG. 3, the top emission type organic EL display device includes a glass substrate 1 (refractive index: about 1.5) and a passivation layer which is disposed on the glass substrate 1 and is made of SiNx, SiON or the like. 2, disposed on the passivation layer 2, an interlayer insulating layer 3 made of acrylic resin, and the like, disposed on the passivation layer 2 and adjacent to the interlayer insulating layer 3, an organic thin film transistor (TFT) 4, Arranged on the insulating layer 3, an organic resin material (refractive index: about 1.5), a planarization layer 6, and a transparent electrode (anode) 7 (refractive index: made of ITO or the like disposed on the planarization layer 6). 1.9), an organic compound layer 8 (refractive index: about 1.8) disposed on the transparent electrode (anode) 7 and including a light-emitting layer, and the like, disposed on the organic compound layer 8, aluminum, silver Opposite made of The electrode (semi-transmissive cathode) 9 and the planarizing layer 6 are disposed adjacent to the transparent electrode (anode) 7, the organic compound layer 8 and the counter electrode (semi-transmissive cathode) 9. A bank 10, a counter electrode (semi-transmissive cathode) 9, a sealing layer 11 made of SiNx, SiON or the like, an adhesive layer 12 made of epoxy resin or the like, placed on the sealing layer 11, The substrate 13 is disposed on the adhesive layer 12 and made of glass or the like.
The interlayer insulating layer 3 and the planarizing layer 6 also have a function as a planarizing film that planarizes the organic thin film transistor (TFT) 4.
Vias 14 are formed in the interlayer insulating layer 3 and the planarizing layer 6, and the transparent electrode (anode) 7 and the organic thin film transistor (TFT) 4 are connected.
Further, since the thickness of the planarizing layer 6 is as thin as 2 μm to 10 μm, the via 14 can be easily formed, and the manufacturing cost can be reduced.
The planarizing layer 6 contains fine particles having a refractive index higher than that of the organic resin material.

The organic light emitting display device may have a resonator structure. For example, a multilayer mirror made of a plurality of laminated films having different refractive indexes, a transparent or translucent electrode, a light emitting layer, and a metal electrode are superimposed on a transparent substrate. The light generated in the light emitting layer resonates repeatedly with the multilayer mirror and the metal electrode as a reflection plate.
In another preferred embodiment, a transparent or translucent electrode and a metal electrode each function as a reflecting plate on the transparent substrate, and light generated in the light emitting layer resonates and resonates between them.
In order to form the resonance structure, the optical path length determined from the effective refractive index of the two reflecting plates and the refractive index and thickness of each layer between the reflecting plates is set to an optimum value for obtaining a desired resonance wavelength. Adjusted. The calculation formula in the case of the first embodiment is described in JP-A-9-180883. The calculation formula in the case of the second aspect is described in Japanese Patent Application Laid-Open No. 2004-127795.

  As a method of making the organic electroluminescent display device of a full color type, for example, as described in “Monthly Display”, September 2000, pages 33 to 37, three primary colors (blue (B) , Green (G), red (R)), a three-color light emitting method in which organic electroluminescent elements that emit light corresponding to green (G) and red (R)) are arranged on a substrate, and white light emitted by a white light emitting organic electroluminescent element through a color filter. There are known a white method for separating primary colors, a color conversion method for converting blue light emitted by an organic electroluminescent element for blue light emission into red (R) and green (G) through a fluorescent dye layer, and the like. Moreover, the planar light source of a desired luminescent color can be obtained by using combining the organic electroluminescent element of the different luminescent color obtained by the said method. For example, a white light-emitting light source that combines blue and yellow light-emitting elements, a white light-emitting light source that combines blue, green, and red light-emitting elements.

  The present invention will be described more specifically with reference to the following examples. The materials, reagents, substance amounts and ratios, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples.

(Bank formation)
After depositing ITO (Indium Tin Oxide) as a positive electrode on a 0.7 mm thick, 25 mm square glass substrate to a thickness of 150 nm, etching and cleaning were performed. The substrate on which the ITO film was formed was placed in a cleaning container and subjected to ultrasonic cleaning in 2-propanol, and then subjected to UV-ozone treatment for 30 minutes.
A bank having a thickness of 5 μm and a width of 50 μm was formed on the ITO electrode using polyimide: HD-8820 (product name of Hitachi Chemical DuPont Microsystems).
When the shape at this time was measured using a laser microscope: VK-9700 (Keyence product name), it was trapezoidal, the tapered portion was 50 μm wide and 4 μm high, and the upper side was 40 μm wide and high. It was confirmed that the film had a gentle curvature of 1 μm and no flat portion.

(Bank fluorination treatment)
According to the method of the eighth embodiment described in Japanese Patent No. 3328297, the bank surface was subjected to fluorine treatment.

(Example 1: Pt complex)
<Production of organic electroluminescence device>
The subsequent spin coating, drying, annealing, and baking were performed in a glove box (dew point -60 ° C., oxygen concentration 10 ppm). Next, on the pixel region of the anode (ITO) on which the bank was formed, the following structural formula 2 parts by mass of PTPDES (produced by Chemipro Kasei Co., Ltd., weight average molecular weight = 13000. N represents the number of repetitions of the structure in parentheses and is an integer) 98 parts by mass of cyclohexanone for electronics industry (manufactured by Kanto Chemical) After coating the hole injection layer coating solution dissolved or dispersed in, the film was dried at 120 ° C. for 10 minutes and annealed at 160 ° C. for 60 minutes to form a hole injection layer having a thickness of 40 nm.

Next, 4 parts by mass of a hole transport material HTL-1 (HTL-1 described in US Pat. No. 2008/0220265) having the following structure is dissolved in 996 parts by mass of methyl isobutyl ketone (manufactured by Kanto Chemical Co., Ltd.) to transport holes. A layer coating solution was prepared.
This hole transport layer coating solution was coated on the hole injection layer and dried at 150 ° C. for 30 minutes to form a 10 nm thick hole transport layer.

  Next, as the light emitting layer, 16.3 parts by mass of the host liquid crystal compound H-1 having the following structure, 1.7 parts by mass of the modified trimethylolpropane triacrylate represented by the following structural formula, and the following structural formula are used. 0.5 parts by mass of a photopolymerization initiator (IRGACURE 907) and 2 parts by mass of phosphorescent material E-1 having the following structure were dissolved in 979.5 parts by mass of 2-butanone (manufactured by Kanto Chemical) for electronic industry. Alternatively, dispersed, molecular sieve (trade name: Molecular sieve 3A 1/16, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the light-emitting layer was prepared by filtration using a syringe filter with a pore size of 0.22 μm in a glove box. The liquid was coated in a glove box. It was confirmed that the coating layer transitioned from a liquid crystal phase (Nd phase) to an isotropic phase by heating at 135 ° C. After annealing at 150 ° C. for 30 minutes, UV exposure is performed for 10 minutes using a UV chamber: ELC-500 (manufactured by ELCTRO-LITE CORPORATION), and baking is performed at 80 ° C. for 30 minutes to correct the 40 nm-thick luminescent layer. Formed on the hole transport layer

  As an adjacent layer, a triphenylene compound AD-1 having the following structure was deposited by a vacuum deposition method to form a 5 nm thick layer on the light emitting layer.

  Next, BAlq (Bis- (2-methyl-8-quinolinolato) -4- (phenyl-phenolate) -aluminum- (III)) was deposited by a vacuum deposition method, and an electron transport layer having a thickness of 35 nm was formed as an adjacent layer. Formed on top.

Next, lithium fluoride (LiF) was deposited on the electron transport layer to form an electron injection layer having a thickness of 1 nm.
Next, metal aluminum was vapor-deposited on the electron injection layer to form a cathode having a thickness of 70 nm.
The produced laminate was put in a glove box substituted with argon gas, and sealed using a stainless steel sealing can and an ultraviolet curable adhesive (XNR5516HV, manufactured by Nagase Ciba Co., Ltd.).

(Example 2: Pyrene derivative)
An organic electroluminescent element was produced in the same manner as in Example 1 except that the light emitting layer was formed as described below.
As a light emitting layer, 17 parts by mass of the host liquid crystal compound H-1, 2 parts by mass of the modified trimethylolpropane triacrylate, 0.5 parts by mass of the photopolymerization initiator, and a fluorescent light emitting material E having the following structure -2 (Journal of Materials Chemistry, 2007, 17, 1392-1398) is dissolved or dispersed in 979.5 parts by mass of methyl isobutyl ketone (manufactured by Kanto Chemical Co., Inc.), and molecular sieve (trade name: Molecular sieve 3A 1/16, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and a light emitting layer coating solution prepared by filtration using a syringe filter having a pore size of 0.22 μm in a glove box was coated in the glove box. It was confirmed that the coating layer transitioned from a liquid crystal phase (Nd phase) to an isotropic phase by heating at 120 ° C. After annealing at 130 ° C. for 30 minutes, UV exposure is performed for 10 minutes using a UV chamber: ELC-500 (manufactured by ELCTRO-LITE CORPORATION), and baking is performed at 80 ° C. for 30 minutes to correct the 40 nm thick light-emitting layer. Formed on the hole transport layer.

(Example 3)
A luminescent material similar to that in Example 2 was used except that the host material used for the luminescent layer was changed to a host liquid crystal compound H-2 (compound described in JP-A-10-321371) having the following structure. It was confirmed that the coating layer transitioned from the liquid crystal phase to the isotropic phase at 90 ° C. A light emitting layer was formed by annealing at 120 ° C. for 30 minutes. Instead of vapor deposition of metallic aluminum as a cathode, copper phthalocyanine (CuPc) is deposited as a buffer layer to a thickness of 20 nm by vacuum deposition, and then an Al: Li alloy (weight ratio 97: 3) as a cathode is sputtered. An organic electroluminescent element was produced in the same manner as in Example 1 except that the film was formed by the method.

Example 4
On the hole transport layer, 4.75 parts by mass of a compound (melting temperature: 125 ° C.) represented by the following structural formula H-3 as a host material and a trade name: Ir (ppy) ₃ (Chemipro) as a phosphorescent material Organic electroluminescence in the same manner as in Example 1 except that 0.25 part by mass is used, an annealing treatment is performed at 150 ° C. for 30 minutes, a light emitting layer is formed, and AD-1 is not formed. An element was produced.

(Comparative Example 1)
Using a metal mask so that only the bank is irradiated with plasma, atmospheric pressure plasma: S-5000BM is used on the bank, plasma irradiation: 1 minute (distance to torch: 5 mm, gas used: nitrogen), hydrophilicity The treatment was performed. Thereafter, an organic electroluminescent element was produced in the same manner as in Example 1.

<Measurement method of contact angle>
Contact angle meter: Using Drop Master 300 (manufactured by Kyowa Interface Science Co., Ltd.), 2 μL of pure water was dropped, and the contact angle was measured. In addition, the contact angle made the average value of 10 places the representative value.
As for the contact angle of the light emitting layer, the contact angle of the film subjected to the annealing treatment and the baking treatment was measured.

<Surface roughness Ra evaluation>
Immediately after the application and after the annealing treatment, Ra of the observation area of 2.5 mm × 1.8 mm was measured using a microscope (trade name: Wyco NT1100, manufactured by Beco).
<Confirmation of light emitting layer material on bank>
Before and after applying the light emitting layer, the shape of the upper part of the bank was confirmed by using a laser microscope: VK-9700 (Keyence product name), and the presence or absence of organic substances was observed under observation of 150 times the objective lens.

In Examples 1 to 4 and Comparative Example 1, the contact angle of the hole transport layer was 87.5 °.
As is apparent from Table 1, in Examples 1 to 4 that satisfy the relationship of the contact angle with pure water according to the present invention, there was no adhesion of organic substances on the upper part of the bank, whereas in Comparative Example 1 that did not satisfy this relationship, the bank There was organic adhesion on the top.
As can be seen from the results of surface roughness before and after annealing, the coating liquid containing a liquid organic substance or liquid crystalline organic substance is self-leveled by an annealing process (leveling process), and the smoothness of the film is improved. The surface roughness was reduced. The self-leveling property was remarkable in Example 4 using the compound H-3 corresponding to the liquid organic substance.

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Passivation layer 3 ... Interlayer insulation layer 4 ... Transistor (TFT)
6 ... Flattening layer 7 ... Transparent electrode (anode)
8 ... Light emitting layer (organic compound layer)
9 ... Counter electrode (cathode)
DESCRIPTION OF SYMBOLS 10 ... Bank 11 ... Sealing layer 12 ... Adhesive layer 13 ... Substrate 14 ... Via 100 ... Organic electroluminescence display device 21 ... Patterning substrate 22 ... Substrate 23 ... Bank 24 ... Pixel region 25 ... Light emitting layer 26 ... Hole injection layer or hole transport layer

Claims (15)

A method of manufacturing an organic light emitting display device comprising a patterning substrate having a bank having a curvature and a pixel region partitioned by the bank on the substrate,
A coating liquid containing a liquid organic material or a liquid crystalline organic material is applied to the pixel region in a pattern, and a contact angle θ1 with respect to pure water of a coating surface on which the coating liquid is applied, the coating A method of manufacturing an organic light emitting display device, wherein a contact angle θ2 of a film formed from a liquid with respect to pure water and a contact angle θ3 of the bank with pure water satisfy a relationship of the following formulas (1) and (2).
| Θ2-θ1 | <| θ3-θ2 | Formula (1)
θ2 <θ3 Formula (2)   The contact angle θ1 with respect to pure water of the coating surface on which the coating liquid is applied ≦ the contact angle θ2 with respect to pure water of the film formed from the coating liquid <the contact angle θ3 with respect to pure water of the bank. Manufacturing method of organic electroluminescence display device.   The manufacturing method of the organic electroluminescent display apparatus of Claim 1 or 2 including performing the heating to the said patterning substrate after application | coating of the said coating liquid.   The method for manufacturing an organic light emitting display device according to claim 3, wherein the patterning substrate is heated at 80 ° C. to 220 ° C. 5.   The manufacturing method of the organic electroluminescent display apparatus as described in any one of Claims 1-4 with which the said bank does not have a flat part.   The manufacturing method of the organic electroluminescent display apparatus as described in any one of Claims 1-5 whose said organic substance which has the liquid organic substance or liquid crystallinity is a light emitting layer forming material.   The method of manufacturing an organic light emitting display device according to claim 6, wherein the coating liquid is applied onto a hole injection layer or a hole transport layer formed in the pixel region. The coating surface to which the coating solution is applied is the surface of a hole injection layer or a hole transport layer, and the contact angle θ4 of the hole injection layer or the hole transport layer with respect to pure water, and the θ2 and θ3 are the following formulas The manufacturing method of the organic electroluminescent display apparatus of Claim 7 which satisfy | fills the relationship of (3).
| Θ2-θ4 | <| θ3-θ2 | Equation (3)   The contact angle θ4 of the hole injection layer or the hole transport layer with respect to pure water ≦ the contact angle θ2 of the film formed from the coating liquid with respect to pure water <the contact angle θ3 of the bank with pure water according to claim 8. The manufacturing method of the organic electroluminescent display apparatus of description.   The organic electroluminescence display device according to claim 1, wherein the coating liquid contains an organic substance having liquid crystallinity, and the organic substance having liquid crystallinity is a triphenylene derivative having liquid crystallinity. Method.   The organic electroluminescent display device according to any one of claims 1 to 10, wherein the coating liquid contains an organic substance having liquid crystallinity, and the organic substance having liquid crystallinity is a pyrene derivative having liquid crystallinity. Method.   The organic electroluminescence display device according to claim 1, wherein the coating liquid contains a liquid organic substance, and the liquid organic substance has an organic substance having a melting point in the range of 80 ° C. to 220 ° C. Manufacturing method.   The method of manufacturing an organic light emitting display device according to claim 12, wherein the organic substance having a melting point in the range of 80 ° C. to 220 ° C. is a carbazole derivative having an asymmetric structure. The method for manufacturing an organic light emitting display device according to claim 13, wherein the carbazole derivative having an asymmetric structure is represented by the following general formula (ACz).

In the general formula (ACz), R _As represents a tert-butyl group, a tert-amyl group, or a trimethylsilyl group.   The organic electroluminescent display apparatus manufactured by the manufacturing method of the organic electroluminescent display apparatus as described in any one of Claims 1-14.

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