JP7112432B2 - Composition, Retardation Film for Organic Electroluminescence Display Element, Method for Producing Retardation Film for Organic Electroluminescence Display Element - Google Patents

Description

The present invention relates to a composition, a retardation film for organic electroluminescence display elements, and a method for producing a retardation film for organic electroluminescence display elements.

Retardation films having refractive index anisotropy are applied to various uses such as antireflection films for display devices and optical compensation films for liquid crystal display devices. In particular, in recent years, a circularly polarizing plate including a retardation film has been used in an organic electroluminescence (EL) display device in order to suppress adverse effects due to reflection of external light (Patent Document 1).

JP-A-9-127885

Conventionally, when manufacturing an organic EL display device including a retardation film, a plurality of organic EL display elements 16 including organic light emitting layers 12 and connection terminals 14 are fabricated on a mother substrate 10 as shown in FIG. Regarding the structure of the organic EL display element 16, in order to simplify the explanation, members other than the organic light emitting layer and connection terminals (for example, a pair of electrodes sandwiching the organic light emitting layer, a sealing layer, etc.) are omitted.
Next, the mother substrate is cut to fabricate laminates each including the substrate 20 and the organic EL display element 16 as shown in FIG. Further, as shown in FIG. 3, a retardation film 24 is adhered to the upper side of the organic light-emitting layer 12 of the organic EL display element 16 with an adhesive layer 22 interposed therebetween. Normally, when the retardation film 24 is attached, the retardation film 24 is arranged so as not to cover the connection terminals 14 for connecting to the IC (integrated circuit) of the organic EL display element 16 .

On the other hand, in recent years, from the viewpoint of thinning and improving the flexibility of organic EL display devices, there has been a demand for a mode in which a retardation film is formed directly on an organic EL display element. In this case, a method of forming a retardation film by applying a composition for forming a retardation film on an organic EL display element can be considered.
However, when a conventional composition for forming a retardation film is used, the retardation film is formed so as to cover the connection terminals of the above-described organic EL display device. can't

In view of the above circumstances, the present invention provides a composition capable of forming a retardation film at a predetermined position on an organic EL display element and having excellent display performance of an organic EL display device to which the retardation film is applied. The task is to provide
Another object of the present invention is to provide a retardation film for an organic EL display element and a method for producing the retardation film for an organic EL display element.

As a result of earnestly examining the problems of the prior art, the inventors of the present invention have found that the above problems can be solved by using a composition having a predetermined composition.
That is, the inventors have found that the above problems can be solved by the following configuration.

(1) a polymer having a hydrophilic group, a crosslinkable group, and a mesogenic group;
and a polymerizable compound,
A composition for forming a retardation film arranged on an organic electroluminescence display element.
(2) The composition according to (1), wherein the polymer comprises repeating units having a crosslinkable group and a mesogenic group.
(3) The composition according to (1) or (2), wherein the hydrophilic group and the crosslinkable group are capable of reacting by heating.
(4) The composition according to any one of (1) to (3), wherein the crosslinkable group is a group selected from the group consisting of oxetanyl groups and epoxy groups.
(5) The composition according to any one of (1) to (4), wherein the hydrophilic group is a group selected from the group consisting of a carboxy group and a phenolic hydroxyl group.
(6) The composition according to any one of (1) to (5), further comprising a polymerization initiator.
(7) The composition according to any one of (1) to (6), wherein the polymerizable compound is a polymerizable liquid crystal compound.
(8) A retardation film for an organic electroluminescence display element, which is formed using the composition according to any one of (1) to (7).
(9) The retardation film for an organic electroluminescence display device according to (8), which is a λ/4 plate or a λ/2 plate.
(10) The retardation film for an organic electroluminescence display device according to (8) or (9), which exhibits reverse wavelength dispersion.
(11) an organic electroluminescent display element;
An organic electroluminescence display device comprising a retardation film for an organic electroluminescence display element according to any one of (8) to (10) disposed on the organic electroluminescence display element.
(12) A step of forming a coating film using the composition according to any one of (1) to (7) on a substrate on which an organic electroluminescence display element is arranged;
orienting the mesogenic groups in the coating;
A step of exposing a portion of the coating film;
A method for producing a retardation film for an organic electroluminescence display element, comprising a step of developing the exposed coating film to form a retardation film for an organic electroluminescence display element on the organic electroluminescence display element.

ADVANTAGE OF THE INVENTION According to this invention, the composition which can form a retardation film in the predetermined position on an organic EL display element, and is excellent in the display performance of the organic EL display device to which the retardation film is applied can be provided.
Further, according to the present invention, it is possible to provide a retardation film for an organic EL display element and a method for manufacturing the retardation film for an organic EL display element.

It is a figure showing the manufacturing process of the organic EL display apparatus of a prior art. It is a figure showing the manufacturing process of the organic EL display apparatus of a prior art. It is a figure showing the manufacturing process of the organic EL display apparatus of a prior art. 4 is a diagram for explaining the procedure of step 1; FIG. FIG. 10 is a diagram for explaining the procedure of step 3; FIG. 10 is a diagram for explaining the procedure of step 4;

The present invention will be described in detail below. In this specification, the numerical range represented by "-" means a range including the numerical values described before and after "-" as lower and upper limits. First, the terms used in this specification will be explained.

In the present invention, Re(λ) and Rth(λ) represent in-plane retardation and thickness direction retardation at wavelength λ, respectively. Unless otherwise specified, the wavelength λ is 550 nm.
In the present invention, Re(λ) and Rth(λ) are values measured at wavelength λ with AxoScan OPMF-1 (manufactured by Optoscience). By entering the average refractive index ((nx+ny+nz)/3) and film thickness (d (μm)) in AxoScan,
Slow axis direction (°)
Re(λ)=R0(λ)
Rth(λ)=((nx+ny)/2−nz)×d
is calculated.
Note that R0(λ), which is displayed as a numerical value calculated by AxoScan OPMF-1, means Re(λ).

In this specification, the refractive indices nx, ny and nz are measured using an Abbe refractive index (NAR-4T, manufactured by Atago Co., Ltd.) using a sodium lamp (λ=589 nm) as the light source. When measuring the wavelength dependence, it can be measured by using a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.) in combination with an interference filter.
In addition, the values in the polymer handbook (JOHN WILEY & SONS, INC.) and various optical film catalogs can be used. Average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), Polystyrene (1.59).
In this specification, the Nz factor is a value given by Nz=(nx-nz)/(nx-ny).

In this specification, "visible light" means light with a wavelength of 380 to 780 nm.
Also, in this specification, angles (e.g., angles such as "90°") and their relationships (e.g., "perpendicular", "parallel", and "crossing at 45°") are referred to as the technology to which the present invention belongs. It shall include the margin of error allowed in the field. For example, it means that it is within the range of a strict angle of ±10°, and the error from the strict angle is preferably 5° or less, more preferably 3° or less.

As used herein, the "absorption axis" of a polarizer means the direction of highest absorbance. "Transmission axis" means the direction that forms a 90° angle with the "absorption axis".

A composition for forming a retardation film disposed on the organic electroluminescence display element of the present invention (composition for forming an organic electroluminescence retardation film) (hereinafter also simply referred to as "composition of the present invention") One of the features of is the use of a polymer having a hydrophilic group, a crosslinkable group, and a mesogenic group.
By having a hydrophilic group in the polymer, developability is imparted to the coating film described in detail later. In addition, when the polymer has a crosslinkable group, phase separation between the polymers and/or between the polymer and the polymerizable compound can be suppressed, and as a result, the display performance of the organic EL display device is excellent. In addition, when the polymer has a mesogenic group, a phase difference can be expressed. Furthermore, when the composition of the present invention contains a polymerizable liquid crystal compound, since the polymer has a mesogenic group, the compatibility between the polymer and the polymerizable liquid crystal compound is excellent, and the removal of the coating film by the developer proceeds efficiently. do.

The composition of the present invention comprises a polymer having hydrophilic groups, crosslinkable groups and mesogenic groups, and a polymerizable compound.
Each component contained in the composition of the present invention will be described in detail below.

<Polymer Having Hydrophilic Group, Crosslinkable Group, and Mesogenic Group>
The polymer has hydrophilic groups.
Hydrophilic groups include, for example, carboxy groups, hydroxyl groups, sulfo groups, and amino groups. Among them, a carboxy group or a phenolic hydroxyl group is preferable, and a carboxy group is more preferable, in terms of better reactivity with a crosslinkable group to be described later.
In addition, a phenolic hydroxyl group intends the hydroxyl group directly couple|bonded with an aromatic-hydrocarbon ring group.

The polymer preferably contains repeating units having hydrophilic groups. The number of hydrophilic groups in each repeating unit is not particularly limited, and may be one or plural (two or more).
Also, the number of hydrophilic groups may be one, or two or more.
As the repeating unit having a hydrophilic group, a repeating unit represented by formula (1) is preferable.

R ¹ represents a hydrogen atom or an alkyl group.
L ¹ represents a single bond or a divalent linking group. Although the divalent linking group is not particularly limited, for example, any one or more selected from the group consisting of —O—, —CO—, —NR ^A —, and divalent hydrocarbon groups Combined groups are included. ^RA represents a hydrogen atom or an alkyl group.
Examples of the divalent hydrocarbon group include an alkylene group, an alkenylene group (e.g. -CH=CH-), an alkynylene group (e.g. -C≡C-), and an arylene group (e.g. phenylene group). mentioned. The alkylene group may be linear, branched, or cyclic. The number of carbon atoms is preferably 1-10, more preferably 1-6, and even more preferably 1-4.

X represents a hydrophilic group. The definition of the hydrophilic group is as described above.

In addition, as described above, the polymer preferably contains a repeating unit having a carboxyl group or a phenolic hydroxyl group.
Repeating units having a carboxyl group include repeating units derived from unsaturated carboxylic acids. Unsaturated carboxylic acids include unsaturated monocarboxylic acids and unsaturated polycarboxylic acids.
Examples of unsaturated monocarboxylic acids include acrylic acid, methacrylic acid, crotonic acid, α-chloroacrylic acid, cinnamic acid, 2-(meth)acryloyloxyethyl-succinic acid, 2-(meth)acryloyloxy Ethylhexahydrophthalic acid and 2-(meth)acryloyloxyethyl-phthalic acid can be mentioned.
Examples of unsaturated polycarboxylic acids include maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid.
The unsaturated polycarboxylic acid may also be its acid anhydride. Specific examples include maleic anhydride, itaconic anhydride, and citraconic anhydride.
The unsaturated polycarboxylic acid may also be a mono(2-methacryloyloxyalkyl) ester of a polycarboxylic acid, such as mono(2-acryloyloxyethyl) succinate, mono(2 -methacryloyloxyethyl), mono(2-acryloyloxyethyl) phthalate, and mono(2-methacryloyloxyethyl) phthalate.
Furthermore, the unsaturated polycarboxylic acid may be a mono(meth)acrylate of dicarboxyl-terminated polymers at both ends thereof, such as ω-carboxypolycaprolactone monoacrylate and ω-carboxypolycaprolactone monomethacrylate. .
The unsaturated carboxylic acids also include acrylic acid-2-carboxyethyl ester, methacrylic acid-2-carboxyethyl ester, maleic acid monoalkyl ester, fumaric acid monoalkyl ester, and 4-carboxystyrene.

Specific examples of repeating units having a carboxy group include the following.

Repeating units having a phenolic hydroxyl group include repeating units represented by formula (1-1).

R ¹¹ represents a hydrogen atom or an alkyl group.
L ¹¹ represents a single bond or a divalent linking group. The definition of the divalent linking group is the same as the definition of the divalent linking group represented by L ¹ described above.
R ¹² represents a halogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms.
a represents an integer of 1 to 5, b represents an integer of 0 to 4, and a+b is 5 or less.
In addition, when two or more R ¹² are present, these R ¹² may be different from each other or may be the same.

The content of the repeating unit having a hydrophilic group in the polymer is not particularly limited, but it is easier to form a retardation film at a predetermined position, and the display performance of the organic EL display device to which the retardation film is applied is improved. At least one of the more excellent points can be obtained (hereinafter also simply referred to as "the point where the effect of the present invention is more excellent"), with respect to the mass of all repeating units in the polymer (100% by mass), 5 to 40 mass % is preferable, and 10 to 30% by mass is more preferable.
Only one repeating unit having a hydrophilic group may be used, or two or more thereof may be used.

The polymer has crosslinkable groups. In addition, a crosslinkable group is a group different from a hydrophilic group.
Examples of crosslinkable groups include oxetanyl groups, epoxy groups, acryloyl groups, methacryloyl groups, thiol groups, halogenated benzyl groups, carboxylic anhydride groups, cyanate ester groups, isocyanate groups, aldehyde groups, aziridine groups, and alkoxysilyl groups. groups.
As for the combination of the hydrophilic group and the crosslinkable group, it is preferable that the hydrophilic group and the crosslinkable group are capable of reacting by heating, because the chemical resistance of the retardation film is more excellent. Combinations of such hydrophilic groups and crosslinkable groups include, for example, a combination of a carboxy group and an oxetanyl group, a combination of a carboxy group and an epoxy group, a combination of a phenolic hydroxyl group and an oxetanyl group, and a phenolic hydroxyl group. and an epoxy group.

The polymer preferably contains repeat units having crosslinkable groups.
As the repeating unit having a crosslinkable group, a repeating unit represented by formula (2) is preferable.

^R2 represents a hydrogen atom or an alkyl group.
L ² represents a single bond or a divalent linking group. The definition of the divalent linking group is the same as the definition of the divalent linking group represented by L ¹ described above.
As will be detailed later, the repeating unit having a crosslinkable group may also have a mesogenic group, for example, L ² may contain a mesogenic group.

Y represents a crosslinkable group. The definition of the crosslinkable group is as described above.

The content of the repeating unit having a crosslinkable group in the polymer is not particularly limited, but from the viewpoint of more excellent effects of the present invention, it is preferably 5 to 85% by mass with respect to the mass of all repeating units in the polymer, and 20 ~80% by mass is more preferred.
Only one kind of repeating unit having a crosslinkable group may be used, or two or more kinds thereof may be used.

The polymer has mesogenic groups.
A mesogenic group is a functional group that is rigid and has orientation. The structure of the mesogenic group includes, for example, a plurality of groups selected from the group consisting of aromatic ring groups (aromatic hydrocarbon ring groups and aromatic heterocyclic groups) and alicyclic groups, and a direct or divalent linking group. (For example, --CO--, --O--, --NR ^A -- (R ^A represents a hydrogen atom or an alkyl group), or a group combining these).
More specifically, the mesogenic group includes a group represented by formula (A).
Formula (A) −(L ^a −L ^b ) _n −
L ^a represents a divalent aromatic ring group or a divalent alicyclic group.
The divalent aromatic ring group includes a divalent aromatic hydrocarbon ring group (eg, phenylene group) or a divalent aromatic heterocyclic group.
A cyclohexylene group is mentioned as a divalent alicyclic group.
L ^b represents a single bond, —CO—, —O—, —NR ^A —, or a group combining these (eg, —CO—O—). ^RA represents a hydrogen atom or an alkyl group.
n represents an integer of 2 or more. Among them, 2 to 5 are preferable, and 2 to 3 are more preferable.

Preferably, the polymer comprises repeating units with mesogenic groups.
Although the content of the repeating unit having a mesogenic group in the polymer is not particularly limited, it is preferably 5 to 85% by mass, based on the mass of all repeating units in the polymer, and 20 to 80% by mass is more preferred.
Only one repeating unit having a mesogenic group may be used, or two or more repeating units may be used.

In the polymer, two or more selected from the group consisting of hydrophilic groups, crosslinkable groups and mesogenic groups may be included in the same repeating unit. In particular, the polymer preferably contains a repeating unit having a crosslinkable group and a mesogenic group, in order to further enhance the effects of the present invention. Repeating units having a crosslinkable group and a mesogenic group include repeating units represented by formula (3).

The definitions of L ^a , L ^b , and n are as explained in formula (A).
^R3 represents a hydrogen atom or an alkyl group.
L ³ and L ⁴ each represent a single bond or a divalent linking group. The definition of the divalent linking group is the same as the definition of the divalent linking group represented by L ¹ described above.
The divalent linking groups represented by L ³ and L ⁴ include, for example, -CO-O-, -CO-O-alkylene group, -CO-O-alkylene group -O-, -O-alkylene Groups —O—, —(O-alkylene group) _m —, and —CO—O—(alkylene group —O) _m — are included. m represents an integer of 2 or more, and although the upper limit is not particularly limited, 5 or less is preferable.
Z represents a crosslinkable group. The definition of the crosslinkable group is as described above.

The content of the repeating unit having a crosslinkable group and a mesogenic group in the polymer is not particularly limited, but from the point of view of more excellent effects of the present invention, 50 to 95% by mass based on the mass of all repeating units in the polymer. Preferably, 60 to 90% by mass is more preferable.
As for the repeating units having a crosslinkable group and a mesogenic group, only one type may be used, or two or more types may be used.

Examples of the monomer that constitutes the repeating unit represented by formula (3) by polymerization include the following. One acryloyl group in the following monomer is polymerized to form the repeating unit represented by formula (3).

The polymer includes repeating units other than the above-described repeating units (repeating units having a hydrophilic group, repeating units having a crosslinkable group, repeating units having a mesogenic group, and repeating units having a crosslinkable group and a mesogenic group). may contain
Examples of monomers that can constitute other repeating units include styrenes, (meth)acrylic acid alkyl esters, (meth)acrylic acid cyclic alkyl esters, (meth)acrylic acid aryl esters, unsaturated dicarboxylic acid diesters, bicyclo unsaturated Saturated compounds, maleimide compounds, unsaturated aromatic compounds, conjugated diene compounds, and other unsaturated compounds are included.

The weight average molecular weight of the polymer is preferably 1,000 to 200,000, more preferably 2,000 to 50,000 in terms of polystyrene.
The ratio (dispersion degree) between the number average molecular weight and the weight average molecular weight is preferably 1.0 to 5.0, more preferably 1.0 to 3.5.
In the measurement by the GPC (Gel Permeation Chromatography) method, for example, HLC-8120 (manufactured by Tosoh Corporation) is used, and TSKgel Multipore HXL-M (manufactured by Tosoh Corporation, 7.8 mm ID × 30.0 cm) is used as a column for elution. THF (tetrahydrofuran) can be used as the liquid.

Although the acid value of the polymer is not particularly limited, it is preferably from 20 to 300 mgKOH/mg, more preferably from 50 to 250 mgKOH/mg, from the viewpoint that the effects of the present invention are more excellent.

A method for synthesizing the polymer is not particularly limited, and includes known methods. For example, a method of polymerizing a mixture containing a radically polymerizable monomer having a hydrophilic group, a radically polymerizable monomer having a crosslinkable group, and a radically polymerizable monomer having a mesogenic group in an organic solvent using a radical polymerization initiator. There is

Although the content of the polymer in the composition of the present invention is not particularly limited, it is preferably 10 to 95% by mass, preferably 20 to 90% by mass, based on the total solid content in the composition, from the viewpoint that the effect of the present invention is more excellent. %, more preferably 20 to 80% by mass.
The solid content is meant to be a component capable of forming a retardation film, and does not include a solvent. Even if the component capable of forming the retardation film is liquid, it is treated as a solid content.

<Polymerizable compound>
A polymerizable compound is a compound having a polymerizable group.
Although the type of the polymerizable group is not particularly limited, a polymerizable group capable of radical polymerization or cationic polymerization is preferred.
A known radically polymerizable group can be used as the radically polymerizable group, and an acryloyl group or a methacryloyl group is preferable.
As the cationically polymerizable group, known cationically polymerizable groups can be used. groups.

Although the number of polymerizable groups in the polymerizable compound is not particularly limited, it is preferably 6 or less.
It is also preferred that the polymerizable compound has both a radically polymerizable group and a cationically polymerizable group.

Polymerizable compounds include, for example, polyfunctional radically polymerizable compounds. Specific examples include those described in paragraphs [0018] to [0020] of JP-A-2002-296423.

As the polymerizable compound, a polymerizable liquid crystal compound is preferable. A polymerizable liquid crystal compound is a compound having a polymerizable group and exhibiting liquid crystallinity.
Although the type of the polymerizable liquid crystal compound is not particularly limited, it can be classified into a rod-like type (rod-like liquid crystal compound) and a disk-like type (disk-like liquid crystal compound, discotic liquid crystal compound) according to its shape. Furthermore, there are low-molecular-weight types and high-molecular-weight types, respectively. Polymers generally refer to those having a degree of polymerization of 100 or more (Polymer Physics: Phase Transition Dynamics, Masao Doi, p. 2, Iwanami Shoten, 1992). Two or more kinds of rod-like liquid crystal compounds, two or more kinds of discotic liquid crystal compounds, or mixtures of rod-like liquid crystal compounds and discotic liquid crystal compounds may be used.

The content of the polymerizable compound in the composition of the present invention is not particularly limited, but from the viewpoint that the effect of the present invention is more excellent, the total solid content in the composition is preferably 5 to 85% by mass, and 20 to 70% by mass is more preferred.

<Others>
The composition of the present invention may contain components other than the polymer and polymerizable compound described above.
For example, the composition of the invention may contain a polymerization initiator. The polymerization initiator to be used is selected according to the type of polymerization reaction, and examples thereof include thermal polymerization initiators and photopolymerization initiators. Examples of photopolymerization initiators include α-carbonyl compounds, acyloin ethers, α-hydrocarbon-substituted aromatic acyloin compounds, polynuclear quinone compounds, and combinations of triarylimidazole dimers and p-aminophenyl ketones. mentioned.
The content of the polymerization initiator in the composition of the present invention is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, based on the total solid content of the composition.

Moreover, the composition of the present invention may contain a surfactant.
Surfactants include conventionally known compounds, and fluorine-based compounds are preferred. For example, compounds described in paragraphs [0028] to [0056] in JP-A-2001-330725, and compounds described in paragraphs [0069] to [0126] in Japanese Patent Application No. 2003-295212. be done.

The composition of the present invention may also contain a curing agent having a reactive group capable of reacting with the crosslinkable group. Although the number of reactive groups in the curing agent is not particularly limited, it is preferably two or more, more preferably two to six.
The type of reactive group is not particularly limited, and an optimum group is selected according to the type of crosslinkable group. For example, when the crosslinkable group is an oxetanyl group, the reactive group includes a carboxy group.

Moreover, the composition of the present invention may contain a solvent. Organic solvents are preferred as solvents. Examples of organic solvents include amides (eg, N,N-dimethylformamide), sulfoxides (eg, dimethylsulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, benzene, hexane), alkyl halides (eg, chloroform , dichloromethane), esters (eg methyl acetate, ethyl acetate, butyl acetate), ketones (eg acetone, methyl ethyl ketone), and ethers (eg tetrahydrofuran, 1,2-dimethoxyethane). In addition, you may use together 2 or more types of organic solvents.

The composition may also contain various alignment control agents such as a vertical alignment agent and a horizontal alignment agent. These alignment control agents are compounds capable of horizontally or vertically controlling the alignment of the polymerizable liquid crystal compound on the interface side. The composition may also contain a chiral agent, in which case a twisted nematic phase or a cholesteric phase can be developed.
Furthermore, the composition may contain an adhesion improver, a pigment, a plasticizer, etc., in addition to the above components.

<Method for Producing Retardation Film>
The composition of the present invention is used to form a retardation film arranged on an organic EL display element. As described above, a retardation film can be formed at a predetermined position by using the composition of the present invention.
The method of forming a retardation film for an organic EL display device of the present invention includes the following steps 1 to 4.
Step 1: The composition of the present invention is brought into contact with the substrate on which the organic EL display element is arranged to form a coating film. Step 2: Orienting the mesogenic groups in the coating film. Step 3: Forming the coating film. Step of exposing a part Step 4: Step of developing the exposed coating film and forming a retardation film on the organic EL display element Hereinafter, the procedure of each step will be described in detail.

(Step 1)
Step 1 is a step of forming a coating film using the composition of the present invention on a substrate on which an organic EL display element is arranged. By carrying out this step, as shown in FIG. 4, a laminate including a substrate 30, an organic EL display element 32 including an organic light-emitting layer, and a coating film 34 is obtained.

The type of substrate that supports the organic EL display element is not particularly limited, and examples thereof include glass substrates, metal substrates, ceramic substrates, semiconductor substrates, and resin substrates.
Although the structure of the organic EL display element is not particularly limited, it usually includes at least a pair of electrodes (cathode and anode) and an organic light-emitting layer disposed between the electrodes.
In addition, the organic EL display element usually includes a connection terminal for connecting with an IC together with the organic light-emitting layer. Furthermore, the organic EL display element may contain other members, for example, a sealing layer that covers the organic light-emitting layer.
Also, a plurality of organic EL display elements may be arranged on the substrate as shown in FIG.

A method for forming a coating film using the composition of the present invention is not particularly limited, and examples thereof include a method of coating the composition of the present invention on the substrate. Examples of coating methods include curtain coating, spin coating, slit coating, print coating, spray coating, blade coating, gravure coating, and wire bar.

If necessary, an alignment layer may be formed on the substrate on which the organic EL display element is arranged before forming the coating film using the composition of the present invention. The alignment layer should be arranged at least on the upper side of the organic light-emitting layer in the organic EL display element (on the side opposite to the substrate), and is preferably not arranged on the connection terminal.
The alignment layer is generally polymer-based. Polymers for alignment layers are described in many documents, and many commercial products are available. The polymer utilized is preferably polyvinyl alcohol (PVA), polyimide, or derivatives thereof.
As the alignment layer, a layer subjected to a known rubbing treatment is preferable. A photo-alignment layer may also be used as the alignment layer.
In particular, when forming regions with different alignment directions in the plane of the retardation film, it is preferable to use a photo-alignment layer in that patterning can be easily realized by adjusting the polarization axis of polarized light irradiation in the photo-alignment treatment. .

As the photo-alignment layer, a known material can be used, but if a photo-curable photo-alignment layer is used, the surface caused by rubbing dust and film fragments generated during peeling can be removed without applying heat to the substrate. This is preferable because a high-quality alignment layer can be formed without causing any defects.
As such a material, for example, a photo-alignment layer-forming composition containing a polymer having a photo-alignment group, a polymerizable monomer, and a photopolymerization initiator can be used. Specifically, the composition described in paragraph 0241 of JP-A-2014-533376, paragraph 0087 of JP-A-2015-527615, and paragraph 0134 of JP-A-2016-535158.

The thickness of the orientation layer is preferably 0.01 to 10 μm.
Note that the alignment layer may be removed at the same time as Step 4, which will be described later.
In the case of the above-mentioned photocurable alignment film, the area where the coating film is to be removed in step 4 described later, such as the wiring connection portion, is prevented from being photocured by shielding light. Then, the alignment film can be removed in advance by rinsing the substrate with an appropriate solvent or developer prior to step 2, which will be described later. By doing so, if the retardation film is removed in step 4, a state in which the region on the substrate is exposed is realized.

(Step 2)
Step 2 is a step of orienting the mesogenic groups in the coating film. When the coating film contains a polymerizable liquid crystal compound, in step 2, both the mesogenic group and the polymerizable liquid crystal compound are oriented.
Specific treatment methods (orientation treatment) in step 2 include a method of heating the coating film and a method of drying the coating film at room temperature. In the case of a thermotropic liquid crystal compound, the liquid crystal phase formed by alignment treatment can generally be caused to transition by a change in temperature. In the case of a lyotropic liquid crystal compound, the transition can also be achieved by changing the composition ratio such as the amount of solvent.
The conditions for heating the coating film are not particularly limited, but the heating temperature is preferably 50 to 150° C., and the heating time is preferably 10 seconds to 5 minutes.

(Step 3)
Step 3 is a step of exposing a portion of the coating film. In this step, as shown in FIG. 5, a partial area of the coating film 34 is exposed. Polymerization of the polymerizable compound proceeds in the exposed portion 36 and becomes insoluble in the developer used in step 4 described later. On the other hand, in the unexposed area 38 , the polymerization of the polymerizable compound does not progress and remains soluble in the developer used in step 4 .
In order to form a retardation film above the organic light-emitting layer in the organic EL display device, it is preferable to expose a region of the coating film located above the organic light-emitting layer. In FIG. 5, the exposed portion of the coating coincides with the area of the coating overlying the organic light emitting layer. In order not to form a retardation film on the connection terminals included in the organic EL display element, it is preferable not to expose the coating film on the connection terminals. That is, in this step, at least the coating film region located above the organic light-emitting layer in the organic EL display element is exposed, and the coating film region located above the connection terminal in the organic EL display element is not exposed. is preferred.

The type of light used for exposure is not particularly limited, but ultraviolet light is preferred.
The exposure method is not particularly limited, and examples thereof include a method of exposing the coating film through a mask having predetermined openings.
There are no particular restrictions on the irradiation dose during exposure, and it is preferably 10 mJ/cm ² to 50 J/cm ² , more preferably 20 mJ/cm ² to 5 J/cm ² . Moreover, in order to accelerate the polymerization reaction, it may be carried out under heating conditions.

Depending on the type of the crosslinkable group, the crosslinkable group may react by carrying out step 3. For example, when the crosslinkable group is an acryloyl group or a methacryloyl group and the radical polymerization reaction proceeds by exposure, the reaction of the crosslinkable group also proceeds.

(Step 4)
Step 4 is a step of developing the exposed coating film to form a retardation film on the organic EL display element. By carrying out this step, as shown in FIG. 6, only the exposed region remains, and in particular, the retardation film 40 (organic EL display element It is preferable that a retardation film for optical fiber is formed.
In addition, as described above, by leaving the coating film region located on the connection terminal in the organic EL display element unexposed, the coating film in that region can be removed in this step, and the retardation film can be formed on the connection terminal. can be prevented from forming

The type of developer used for development is not particularly limited, and an optimum developer (for example, an alkaline developer and an organic solvent-containing developer) is selected according to the type of coating film. Among them, an alkaline developer is preferable because the removability of the coating film is more excellent.
Examples of alkali developing solutions include aqueous solutions containing alkali. Examples of alkaline developers include aqueous alkaline solutions containing quaternary ammonium salts such as tetramethylammonium hydroxide, inorganic alkalis, primary amines, secondary amines, tertiary amines, alcohol amines, or cyclic amines. be done. Among them, an aqueous solution of a quaternary ammonium salt represented by tetramethylammonium hydroxide (TMAH) is preferable as the alkaline developer. An appropriate amount of alcohol and/or surfactant may be added to the alkaline developer. The alkali concentration of the alkali developer is preferably 0.1 to 20 mass %. Further, the pH of the alkaline developer is preferably 10.0 to 15.0.

The method of development treatment is not particularly limited as long as the exposed coating film and the developer can come into contact. A method of immersion can be mentioned.

In addition, you may perform the rinse process using a rinse liquid after development as needed. Pure water can be used as the rinsing liquid.

Moreover, you may heat-process with respect to the coating film in which development processing was performed as needed. By carrying out heat treatment (post-baking treatment), the crosslinkable groups can be reacted to enhance the chemical resistance of the retardation film. In addition, as described above, when the crosslinkable group and the hydrophilic group are capable of reacting by heating, both react by carrying out this treatment.
The temperature of the heat treatment is not particularly limited, preferably 70 to 250°C, more preferably 80 to 200°C. The heat treatment time is not particularly limited, preferably 5 to 180 minutes, more preferably 10 to 120 minutes.

By the method described above, a retardation film for an organic EL display element can be formed at a predetermined position of the organic EL display element.
The in-plane retardation of the retardation film for organic EL display elements formed using the composition of the present invention is not particularly limited, and an optimum value is selected according to the intended use. Among them, the retardation film is preferably a λ/4 plate or a λ/2 plate from the viewpoint of using it as a retardation film of a circularly polarizing plate to be described later.
A λ/4 plate (a plate having a λ/4 function) is a plate that has the function of converting linearly polarized light of a specific wavelength into circularly polarized light (or circularly polarized light into linearly polarized light). More specifically, it is a plate that exhibits an in-plane retardation of λ/4 (or an odd multiple thereof) at a predetermined wavelength λnm.
Among them, the in-plane retardation Re(550) at a wavelength of 550 nm is preferably 100 to 200 nm, more preferably 120 to 160 nm, in terms of better function as a circularly polarizing plate.
A λ/2 plate is an optically anisotropic layer in which the in-plane retardation Re(λ) at a specific wavelength λnm satisfies Re(λ)≈λ/2. Among others, the in-plane retardation Re(550) at a wavelength of 550 nm is preferably 210 to 300 nm.

A retardation film for an organic EL display device formed using the composition of the present invention preferably exhibits reverse wavelength dispersion (characteristic in which in-plane retardation increases as the measurement wavelength increases).

Incidentally, the above method may be carried out a plurality of times to laminate a plurality of retardation films for organic EL display elements. That is, the composition of the present invention may be used to form only one layer of the retardation film at a predetermined position of the organic EL display element, or two or more layers of the retardation film may be formed. In the case of forming two or more layers, for example, a λ / 2 plate having a forward wavelength dispersion characteristic and a λ / 4 plate having a forward wavelength dispersion characteristic are laminated, and reverse wavelength dispersion is obtained. A laminate of the λ/4 plate shown and a positive C plate can be mentioned.

In addition, a retardation film having other functions can be formed by adding additives such as dyes to the composition of the present invention within the scope of the present invention.
For example, a retardation film exhibiting a twisted nematic phase or a cholesteric phase may be provided as the retardation film. Such a retardation film provides, for example, the function of rotating the polarization axis as an optical rotation layer, or the effect of improving luminance or color reproducibility as a wavelength selective reflection film. Such a retardation film can be obtained by adding a known chiral agent to the composition of the invention. A retardation film exhibiting a cholesteric phase can also be used as a C plate (nx≈ny<nz or nx≈ny>nz) for light of a specific wavelength.
In addition, by including various dyes in the retardation film, it is possible to improve color reproducibility or impart visual effects to improve display performance. Such a dye-containing retardation film can be obtained by adding a dye to the composition of the present invention. For example, a dye having an absorption peak at a wavelength of 480-520 nm or a wavelength of 580-620 nm is useful for widening the color gamut.
In particular, by using a dichroic dye as the dye and orienting the dichroic dye using the orientation of the liquid crystal compound of the composition of the present invention, an anisotropic light absorption property (in-plane direction or oblique direction) can be obtained. direction) can be given to improve the display performance.

<Organic EL display device>
By the method described above, an organic EL display device including an organic EL display element and the organic EL display element retardation film disposed on the organic EL display element is manufactured. In addition, it is preferable that the retardation film for an organic EL display element is arranged so as to be in direct contact with the organic EL display element.
The organic EL display device preferably further includes a polarizer on the retardation film for organic EL display element. For example, when the retardation film for organic EL display elements functions as a λ/4 plate, the combination of the polarizer and the retardation film for organic EL display elements functions as a circularly polarizing plate. When laminating the retardation film for organic EL display element and the polarizer, which is a λ / 4 plate, the in-plane slow axis of the retardation film for organic EL display element and the absorption axis of the polarizer Preferably, the angles are adjusted to 45±10°.
External light reflection is prevented by disposing the circularly polarizing plate on the organic EL display element.

The polarizer may be any member (linear polarizer) that has the function of converting light into specific linearly polarized light, and examples thereof include absorption polarizers.
Absorptive polarizers include, for example, iodine-based polarizers, dye-based polarizers using dichroic dyes, and polyene-based polarizers. Iodine-based polarizers and dye-based polarizers include coating-type polarizers and stretching-type polarizers, and both can be applied. Among them, a polarizer produced by adsorbing iodine or a dichroic dye to polyvinyl alcohol and stretching the resultant is preferable.
In addition, as a method of obtaining a polarizer by stretching and dyeing a laminated film in which a polyvinyl alcohol layer is formed on a substrate, there are disclosed in Japanese Patent Nos. 5048120, 5143918, 5048120, and Methods described in Japanese Patent No. 4691205, Japanese Patent No. 4751481, and Japanese Patent No. 4751486 can be mentioned, and known techniques relating to these polarizers can also be preferably used.
Above all, from the viewpoint of handling, the polarizer is selected from the group consisting of polyvinyl alcohol-based resins (polymers containing —CH ₂ —CHOH— as repeating units, particularly polyvinyl alcohol and ethylene-vinyl alcohol copolymers. at least one is preferred).

Although the thickness of the polarizer is not particularly limited, it is preferably 35 μm or less, more preferably 3 to 25 μm, from the standpoint of excellent handleability and optical properties.

EXAMPLES The present invention will be described more specifically with reference to examples below. The materials, amounts used, ratios, processing details, and processing procedures shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Accordingly, the scope of the invention is not limited to the specific examples shown below.

<Synthesis Example 1: Polymer 1>
Methyl ethyl ketone was placed in a flask and heated to 70° C. under a nitrogen atmosphere. A solution prepared by mixing predetermined amounts of liquid crystal monomer 1, acrylic acid, acrylic acid ethyl ester, and V-65 (manufactured by Wako Pure Chemical Industries, Ltd.) was dropped into the flask over 2 hours. After completion of dropping, the mixture was stirred for 2 hours. Polymer 1 was thereby obtained.
Regarding the content of each repeating unit in the polymer 1 relative to all repeating units, the repeating unit derived from the liquid crystal monomer 1 is 70% by mass, the repeating unit derived from acrylic acid is 13% by mass, and the repeating unit derived from ethyl acrylate. was 17% by mass. Moreover, the weight average molecular weight of polymer 1 was 15,000. Moreover, the acid value of polymer 1 was 101 mgKOH/mg.
The liquid crystal monomer 1 was synthesized with reference to JP-A-11-513019 (WO97/00600).

<Synthesis Example 2: Polymer 2>
Polymer 2 was synthesized according to the same procedure as in Synthesis Example 1, except that Liquid Crystal Monomer 1 was changed to Liquid Crystal Monomer 2.
Note that the content, weight average molecular weight, and acid value of each repeating unit in Polymer 2 are the same as those in Polymer 1, except that the repeating unit derived from Liquid Crystal Monomer 1 is replaced by the repeating unit derived from Liquid Crystal Monomer 2. The repeating unit content, weight average molecular weight, and acid value were the same.
Liquid crystal monomer 2 was synthesized with reference to Japanese Patent Application Laid-Open No. 11-513019 (WO97/00600).

<Synthesis Example 3: Polymer 3>
Polymer 3 was synthesized according to the same procedure as in Synthesis Example 1, except that Liquid Crystal Monomer 1 was changed to Liquid Crystal Monomer 3. Polymer 3 contained acryloyl groups as crosslinkable groups.
Note that the content, weight average molecular weight, and acid value of each repeating unit in Polymer 3 are the same as those in Polymer 1, except that the repeating unit derived from Liquid Crystal Monomer 1 is replaced by the repeating unit derived from Liquid Crystal Monomer 3. The repeating unit content, weight average molecular weight, and acid value were the same.
Further, the liquid crystal monomer 3 was synthesized with reference to Japanese Patent Publication No. 11-513019 (WO97/00600).

<Synthesis Example 4: Polymer C1>
A polymer C1 was synthesized according to the same procedure as in Synthesis Example 1, except that the liquid crystal monomer 1 was changed to the following monomer C1.
Except that the repeating unit derived from the liquid crystal monomer 1 was replaced with the repeating unit derived from the monomer C1, the content of each repeating unit in the polymer C1, the weight average molecular weight, and the acid value were the respective repeating units in the polymer 1. The unit content, weight average molecular weight, and acid number were the same.

<Synthesis Example 5: Polymer C2>
Polymer C2 was synthesized according to the same procedure as in Synthesis Example 1, except that acrylic acid was not used.
Regarding the content of each repeating unit in the polymer C2, the content of the repeating unit derived from the liquid crystal monomer 1 was 70% by mass, and the content of the repeating unit derived from ethyl acrylate was 30% by mass. Moreover, the weight average molecular weight of polymer C2 was 15,000.

<Synthesis Example 6: Polymer C3>
Polymer C3 was synthesized according to the same procedure as in Synthesis Example 1, except that liquid crystal monomer 1 was changed to glycidyl methacrylate.
Except that the repeating unit derived from the liquid crystal monomer 1 was replaced with the repeating unit derived from glycidyl methacrylate, the content of each repeating unit in the polymer C3, the weight average molecular weight, and the acid value were the respective repeating units in the polymer 1. The unit content, weight average molecular weight, and acid number were the same.

<Example 1>
A composition was obtained by dissolving the following components in methyl ethyl ketone and adjusting the solid content concentration to 25% by mass.
The numerical values "83%", "15%" and "2%" in the structural formulas of the liquid crystal monomers represent the content (% by mass) of each monomer with respect to the total mass of the liquid crystal monomers.

Polymer 1 50 parts by mass Liquid crystal monomer 100 parts by mass Polyfunctional monomer 8 parts by mass IRG907 (IRGACURE 907 (manufactured by BASF)) 6 parts by mass F polymer 1 0.25 parts by mass F polymer 2 0.1 parts by mass

<Examples 2 to 4, Comparative Examples 1 to 3>
A composition was obtained according to the same procedure as in Example 1, except that instead of polymer 1, the type and amount of polymer used were changed as shown in Table 1.

<Evaluation>
(Display performance evaluation)
A GALAXY S4 manufactured by SAMSUNG equipped with an organic EL display element (organic EL display panel) was disassembled, and the circularly polarizing plate was peeled off.
Next, on the organic EL display element, a 3% by mass solution of PVA203 (manufactured by Kuraray Co., Ltd.) (solvent ratio: water/methanol = 75/25) was applied by spin coating, and then the resulting organic The EL display element was prebaked on a hot plate at 100° C. for 2 minutes to volatilize the solvent in the coating film and form a PVA layer having a thickness of 0.5 μm.
When the PVA layer was formed, a tape was attached so as to cover the metal electrode connected to the drive element of the organic EL display element, the above treatment was performed, and the tape was peeled off after prebaking. Due to this treatment, no PVA layer was formed on the metal electrodes.
A rubbing treatment was applied in the longitudinal direction of the PVA layer.
Next, each composition of Examples and Comparative Examples was spin-coated to a thickness of 1.0 μm on the rubbed PVA layer, and heat-treated at 90° C. for 120 seconds using a hot plate. . Subsequently, part of the coating film was exposed to light at 90° C. and 100 mJ/cm ² (illuminance: 20 mW/cm ² , i-line). At that time, the portion of the metal electrode (connection terminal) connected to the drive element was prevented from being irradiated with light using a photomask.
Subsequently, using an alkaline developer (2.38% by mass of tetramethylammonium hydroxide (TMAH) aqueous solution), the coating film was developed at 23 ° C. for 60 seconds, and then rinsed with ultrapure water for 1 minute. By doing so, the coating film located on the upper part of the metal electrode that was not irradiated with light was removed, and after rinsing, heat treatment was performed in an oven at 150 ° C. for 30 minutes as a post-baking treatment, so that the organic EL display element. A retardation film was formed on the light emitting layer. The in-plane retardation at a wavelength of 550 nm of the retardation film formed in each example was 125 nm.
A polarizer was laminated on the obtained retardation film so that the angle formed by the in-plane slow axis of the retardation film and the absorption axis of the polarizer was 45°, thereby producing an organic EL display device.
The visibility of the produced organic EL display device was evaluated in a bright room with an illuminance of 200 lux. An image was displayed (black display) on the organic EL display device, and the image definition and the degree of cloudiness were observed when a fluorescent lamp was projected from the front, and evaluated according to the following criteria. Table 1 shows the results. Practically, it needs to be "A" or "B".
A: No cloudiness was visually observed, and the image was clear.
B: Partial cloudiness is slightly visible, and part of the image is slightly unclear.
C: White turbidity is slightly visible on the whole, and the image is slightly unclear.
D: White turbidity is clearly visible on the whole, and the image is unclear.

(Chemical resistance evaluation)
After applying a 3% by mass solution of PVA203 (manufactured by Kuraray Co., Ltd.) (solvent ratio: water/methanol = 75/25) to a glass substrate (10 cm × 10 cm × 0.5 mm, manufactured by Corning, Eagle XG) by spin coating. The glass substrate having the obtained coating film was prebaked on a hot plate at 100° C. for 2 minutes to volatilize the solvent in the coating film and form a PVA layer having a thickness of 0.5 μm.
A rubbing treatment was applied in the longitudinal direction of the PVA layer.
Next, each composition of Examples and Comparative Examples was spin-coated to a thickness of 1.0 μm on the rubbed PVA layer, and heat-treated at 90° C. for 120 seconds using a hot plate. . Subsequently, the entire surface of the coating film is exposed at 100 mJ/cm ² (illuminance: 20 mW/cm ² , i-line) at 90° C., and then the substrate is heated in an oven at 150° C. for 30 minutes to form a retardation film. got
The film thickness (T ¹ ) of the obtained retardation film was measured. Then, the substrate on which the retardation film is formed is immersed in a dimethylsulfoxide:monoethanolamine=7:3 solution at 60° C. for 10 minutes, and then the film thickness (t ¹ ) of the retardation film after immersion is measured. Then, the rate of film thickness change due to immersion {|t ¹ −T ¹ |/T ¹ }×100[%] was calculated and evaluated according to the following criteria. Table 1 shows the results. The smaller the calculated value, the better, and A and B are levels that pose no problem in practice.
A: Less than 4% B: 4% or more and less than 8% C: 8% or more and less than 12% D: 12% or more

The "hydrophilic group" column in Table 1 corresponds to "A" when the polymer has a hydrophilic group, and to "B" when it does not have a hydrophilic group.
The "crosslinkable group" column in Table 1 corresponds to "A" when the polymer has a crosslinkable group, and to "B" when it does not have a crosslinkable group.
The "mesogenic group" column in Table 1 corresponds to "A" when the polymer has a mesogenic group, and to "B" when it does not have a mesogenic group.
In addition, "-" in the "Display performance" column and "Chemical resistance" column in Table 1 means that the composition used did not have developability, so the retardation film could not be formed at the predetermined position. Therefore, it is intended that the evaluation was not conducted.

As shown in Table 1, it was confirmed that a retardation film could be formed at a predetermined position by using the composition of the present invention.
A comparison of Examples 1 to 3 confirmed that chemical resistance was further improved when the crosslinkable group and the hydrophilic group could react (Examples 1 and 2).

<Example 5>
A GALAXY S4 manufactured by SAMSUNG equipped with an organic EL display element (organic EL display panel) was disassembled, and the circularly polarizing plate was peeled off.
Next, the following composition for forming a photo-alignment film was coated on the organic EL display element so that the dry film thickness was about 100 nm, and dried at 80° C. for 2 minutes. Next, the obtained coating film was irradiated with polarized UV (ultraviolet light) (100 mW/cm ² ) at an intensity of 100 mW/cm ² . The UV exposure was performed through a mask so that the metal electrode region connected to the driving element of the organic EL display element was not irradiated with light.

(Composition for forming a photo-alignment film)
The following photo-orientable polymer 30 parts by mass Pentaerythritol tetraacrylate 10 parts by mass Photopolymerization initiator (Irgacure 907, manufactured by BASF) 5 parts by mass Toluene 2250 parts by mass

- Photoalignment polymer (poly[4-methoxy-cinnamate-5-norbornene], Mw = 150,000)

Furthermore, the uncured portion was removed with a solvent. No coating was formed on the metal electrodes by this treatment.

Thereafter, in the same manner as in Example 1, the composition was applied to fabricate an organic EL display device. The in-plane retardation of the produced retardation film at a wavelength of 550 nm was 125 nm. Further, the obtained retardation film exhibited chemical resistance similar to that of Example 1.
No coating film remained on the metal electrode.

<Example 6>
In Example 5, the orientation treatment was carried out except that polarized UV exposure was performed through a polarizing mask designed such that adjacent regions emit polarized light having different polarization directions by 45° in a stripe shape with a width of 2 mm. An organic EL display device was produced in the same manner as in Example 5. The polarizer was bonded such that its absorption axis was at 45° with one of the slow axis directions of the two different orientation regions of the retardation film.
The chemical resistance of the obtained retardation film was "A" as in Example 5.
In addition, regarding the manufactured organic EL display device, when the organic EL display device was set to black display in a bright room with an illuminance of 200 lux and a fluorescent lamp was projected from the front, a bright and dark pattern in a stripe shape with a width of 2 mm was observed. The incident light was faintly reflected at the part. That is, it was shown that the predetermined phase difference patterning was formed on the phase difference film.
No coating film remained on the metal electrode.

In this embodiment, a simple striped pattern is used as a specific example, but if a design with a visual assistance effect is applied instead of the striped pattern, for example, the display performance can be improved based on the user's experience. is clear.

<Example 7>
An organic EL display device was produced in the same manner as in Example 1 by adding a chiral agent to the composition of Example 1. The chemical resistance of the obtained retardation film was "A" as in Example 1.
The obtained retardation layer exhibited a blue reflection color when viewed from the front. The circularly polarizing plate that had been peeled off first was reattached in the original direction, and the luminance during blue display was measured in a dark room. rice field.
No coating film remained on the metal electrode.

REFERENCE SIGNS LIST 10 mother substrate 12 organic light-emitting layer 14 connection terminal 16, 32 organic EL display element 20, 30 substrate 22 adhesive layer 24, 40 retardation film 34 coating film 36 exposed portion 38 unexposed portion

Claims (9)

As the polymer having a mesogenic group, only a polymer having a hydrophilic group, a crosslinkable group, and a mesogenic group,
and a polymerizable compound,
A composition for forming a retardation film disposed on an organic electroluminescence display element,
the polymer comprises repeating units having the crosslinkable group and the mesogenic group;
the polymer comprises a repeating unit having the hydrophilic group,
The content of the repeating unit having a hydrophilic group is 10 to 30% by mass with respect to the mass of all repeating units in the polymer,
The hydrophilic group and the crosslinkable group are capable of reacting by heating,
The composition, wherein the hydrophilic group is a group selected from the group consisting of a carboxy group and a phenolic hydroxyl group. 2. The composition of claim 1, wherein said crosslinkable groups are groups selected from the group consisting of oxetanyl groups and epoxy groups. 3. The composition of claim 1 or 2, further comprising a polymerization initiator. The composition according to any one of claims 1 to 3, wherein the polymerizable compound is a polymerizable liquid crystal compound. A retardation film for an organic electroluminescence display element formed using the composition according to any one of claims 1 to 4. 6. The retardation film for an organic electroluminescence display device according to claim 5, which is a λ/4 plate or a λ/2 plate. 7. The retardation film for an organic electroluminescence display element according to claim 5, which exhibits reverse wavelength dispersion. an organic electroluminescence display element;
An organic electroluminescence display device comprising the retardation film for an organic electroluminescence display element according to any one of claims 5 to 7, disposed on the organic electroluminescence display element. A step of forming a coating film using the composition according to any one of claims 1 to 4 on a substrate on which an organic electroluminescence display element is arranged;
orienting the mesogenic groups in the coating;
exposing a portion of the coating film;
and developing the exposed coating film to form a retardation film for an organic electroluminescence display element on the organic electroluminescence display element.

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