KR102119222B1 - Display device and method of manufacturing the same - Google Patents

Abstract

A display device comprising: a display substrate, an encapsulation substrate facing the display substrate, a filling material positioned between the display substrate and the encapsulation substrate, and comprising a norbornene-based resin, and a sealing material bonding between the display substrate and the encapsulation substrate, and It relates to the manufacturing method.

Description

DISPLAY DEVICE AND METHOD OF MANUFACTURING THE SAME

It relates to a display device and a manufacturing method thereof.

Currently known display devices include liquid crystal displays (LCDs), plasma display panels (PDPs), organic light emitting diode devices (OLED devices), and field emission displays (field emission) display: FED), an electrophoretic display device, and the like.

Such a display device generally includes a display substrate including a thin film transistor, a light emitting layer, and an encapsulation substrate covering the display substrate. In general, a filling material is filled between the display substrate and the encapsulation substrate, and it is required to secure the reliability of the display device by using a material having high temperature stability and excellent shock absorption.

One embodiment provides a display device with improved reliability by using a filler having excellent high temperature stability and shock absorption.

Another embodiment provides a method of manufacturing the display device.

According to one embodiment, a display substrate, an encapsulation substrate facing the display substrate, a filling material comprising a norbornene-based resin located between the display substrate and the encapsulation substrate, and a sealing material bonding between the display substrate and the encapsulation substrate It provides a display device comprising.

The norbornene-based resin may include a cyclic olefin copolymer containing a norbornene-based monomer.

The filling material may have pores.

The pores may have a particle diameter of 1 nm to 10 nm.

The pores can be round or oval.

The filler layer may have a thickness of 1 μm to 100 μm.

The filling material may further include a nano pore forming agent.

The nano pore formers are cyclic ester oligomers, linear ester oligomers, copolymers thereof, methyl methacrylate, hydroxyethyl methacrylate, dimethylamino ethyl methacrylate, ethylene oxide, propylene oxide, their oligomers and their It may include at least one selected from the group consisting of copolymers.

The encapsulation substrate may include aluminum (Al), copper (Cu), tungsten (W), alloys thereof, or a combination thereof.

A getter positioned between the display substrate and the encapsulation substrate may be further included.

The display substrate may include a base substrate, a pair of electrodes formed on the base substrate and facing each other, and an organic emission layer interposed between the pair of electrodes.

According to another embodiment, a step of manufacturing a filler using a norbornene-based resin, forming a porous thin film by applying the filler between the display substrate and the sealing substrate, and using the sealing material between the display substrate and the sealing substrate It provides a method of manufacturing a display device comprising the step of bonding.

The step of forming the porous thin film may include a step of heat treatment at 90° C. to 200° C. in the atmosphere after applying the filler, and heating to 250° C. to 400° C. under a nitrogen atmosphere or vacuum.

The step of forming the porous thin film may include applying the filler by a film attachment method or a liquid coating method.

The liquid coating method may be performed by spin coating, screen printing, inkjet, one drop filling (ODF), or a combination thereof.

The reliability of the display device can be improved by using a filler having excellent high temperature stability and shock absorption.

1 is a cross-sectional view illustrating an organic light emitting diode display according to an embodiment,
FIG. 2 is a schematic view showing an enlarged display unit in FIG. 1.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein.

In the drawings, the thickness is enlarged to clearly express the various layers and regions. The same reference numerals are used for similar parts throughout the specification. When a portion of a layer, film, region, plate, or the like is said to be “above” another portion, this includes not only the case “directly above” the other portion but also another portion in the middle. Conversely, when one part is "just above" another part, it means that there is no other part in the middle.

Hereinafter, a display device according to an exemplary embodiment will be described. Here, an organic light emitting display device will be described as an example of the display device.

1 is a cross-sectional view illustrating an organic light emitting diode display according to an exemplary embodiment.

Referring to FIG. 1, the display device 1000 according to an exemplary embodiment includes a display substrate 100, an encapsulation substrate 200, a filling material 300, and a sealing material 400.

The display substrate 100 includes a base substrate 110 and a display unit 120.

The base substrate 110 may be a glass substrate or a polymer substrate.

The display unit 120 is formed on the base substrate 110 and includes a device region in which active elements such as a thin film transistor (TFT) are formed and a light emitting region in which a light emitting layer is formed. The device area and the display area may be positioned separately or may overlap. The display unit 120 will be described later.

The encapsulation substrate 200 is positioned to face the display substrate 100 and may be made of an aluminum (Al)-containing metal, such as aluminum (Al) or aluminum (Al) alloy.

The encapsulation substrate 200 may protect the display unit 120 by preventing oxygen and moisture from entering from the outside.

The encapsulation substrate 200 may be, for example, a single layer of aluminum-containing metal sheet or a plurality of layers of aluminum-containing metal sheets stacked, and may have a thickness of about 1um to 1000um. By having the above thickness, it is possible to effectively prevent the inflow of oxygen and moisture from the outside, while preventing the warpage due to heat during the process due to the excessively thick thickness.

Among the metals, the encapsulation substrate 200 may include, for example, aluminum (Al), copper (Cu), tungsten (W), alloys thereof, or combinations thereof.

The sealing material 400 is bonded between the display substrate 100 and the encapsulation substrate 200, and may be disposed along the edge of the display substrate 100, for example. The sealing material 400 may be made of, for example, a thermosetting and/or photocurable resin such as an epoxy resin or an acrylic resin.

The filling material 300 is filled in an area defined by the sealing material 400. The filler 300 forms a thin film between the display substrate 100 and the encapsulation substrate 200 to absorb external shock applied to the display device 1000.

The filling material 300 includes a norbornene-based resin.

Here, the norbornene-based resin is not particularly limited as long as it has a norbornene group. For example, the norbornene-based resin may include a cyclic olefin copolymer containing a norbornene-based monomer.

The cyclic olefin copolymer may include a copolymer containing a hydroxy group and a trialkyloxysilyl group to react with a nano-pore forming agent, which will be described later.

The cyclic olefin copolymer containing the norbornene-based monomer may include a copolymer prepared by using an olefin and a cyclic olefin as a chain transfer agent.

The norbornene-based monomer may include, for example, 5-norbornene-2-methanol, cis-5-endo-2,3-dicarboxylic anhydride or dicyclopentadiene.

The norbornene-based resin may be a thermally stable low dielectric polymer copolymer.

The norbornene-based resin is a norbornene-based cyclic olefin copolymer and a dicyclopentadiene cyclic olefin copolymer having a glass transition temperature of about 250°C to 450°C, and is synthesized by using norbornene, dicyclopentadiene and norbornene derivatives as monomers. It can be a copolymer of any composition.

The norbornene-based resin is a compound that has the property of changing its shape only when it is bent or twisted and retaining its shape when no further force is applied, and has excellent shock absorption.

Therefore, when a norbornene-based resin is used as the filling material 300, an external impact applied to the display device 1000 is effectively absorbed to maintain a constant gap between layers of the display device 1000. In addition, irregular surfaces can be sealed even at low pressures to minimize unfilled areas.

In addition, since the norbornene-based resin is excellent in high temperature stability, it has excellent storage reliability due to less occurrence of dark spots even when the display device is stored for a long time.

The filler 300 has a nano-sized particle size, for example, the particle size may be about 1 nm to 10 nm. When the filler 300 has a particle diameter in the above range, the display device 1000 may be applied to the front light emitting panel as the refractive index of the filler 300 is easily adjusted.

The filler 300 may further include a nano pore forming agent.

The nano-pore forming agent may include any compound that is thermally decomposed at a temperature lower than the glass transition temperature of the norbornene-based resin. For example, the nano-pore forming agent may be a compound that is thermally decomposed at a temperature between about 250°C and 400°C. The nano-pore forming agent may include oligomers of cyclic esters such as lactide, glycolide or caprolactone, or oligomers of linear esters such as lactic acid or glycolic acid, or copolymers thereof. In addition, the nano-pore forming agent includes at least one selected from the group consisting of, for example, methyl methacrylate, hydroxyethyl methacrylate, dimethylamino ethyl methacrylate, ethylene oxide, propylene oxide, oligomers thereof, and copolymers thereof. can do.

The pores may have a circular or elliptical shape.

The filling material 300 is filled between the display substrate 100 and the encapsulation substrate 200 to form a thin film, and the thickness of the thin film may be, for example, about 1 μm to 100 μm. When having a thickness in the above range, sufficient impact resistance can be secured.

The display device 1000 may further include a getter 500 between the display substrate 100 and the encapsulation substrate 200.

Hereinafter, the display unit 120 of the display device will be described with reference to FIG. 2 together with FIG. 1.

2 is a schematic diagram illustrating an enlarged display unit 120 in FIG. 1.

Referring to FIG. 2, a buffer layer 115 is formed on the base substrate 110 and a semiconductor layer 154 including a channel region 154a, a source region 154b, and a drain region 154c on the buffer layer 115. ), the gate insulating layer 140, the gate electrode 124, the intermediate layer 180, the source electrode 173, the drain electrode 175 and the passivation film 180 are sequentially stacked.

The lower electrode 22, the light emitting layer 24, and the upper electrode 26 are sequentially stacked on the passivation film 180, and they form one light emitting element L1.

Hereinafter, a method of manufacturing the above-described display device will be described.

A method of manufacturing a display device according to an embodiment includes manufacturing a filler using a norbornene-based resin, forming a porous thin film by applying the filler between the display substrate and the encapsulation substrate, and the display substrate and the encapsulation substrate It includes the step of bonding using a sealing material.

In the step of manufacturing the filler, the filler is manufactured using a norbornene-based resin, and may further include a nano-pore forming agent. The norbornene-based resin and the nano-pore-forming agent have been described above, and thus the description thereof is omitted here.

Hereinafter, a step of forming the porous thin film will be described. The porous thin film is obtained by filling the filler and heat-treating it. The forming of the porous thin film may include a step of heat treatment at about 90° C. to 200° C. in the atmosphere after applying the filler. The residual solvent can be removed by heat treatment at the above temperature.

Subsequently, the method may include heating to 250 to 400° C. under a nitrogen atmosphere or vacuum. As a result of the above process, a thin film having nano-sized pores may be formed. The thin film can be formed by thermally decomposing an organic component used as a nano pore forming agent without crosslinking and curing the filler.

The step of forming the porous thin film may include applying the filler by a film attachment method or a liquid coating method.

Here, the liquid coating method may be performed by, for example, spin coating, screen printing, inkjet, one drop filling (ODF), or a combination thereof.

In the step of bonding the display substrate and the encapsulation substrate using a sealing material, the sealing material 400 may be applied along the edge of the display substrate 100.

In the case of the method described above, the polymer resin is not cured, and by using the thermal decomposition temperature of the thermally decomposable polymer lower than the glass transition temperature of the matrix polymer, nanopores by thermal decomposition are introduced into the polymer thin film to obtain a thin film having a desired refractive index It can be applied as a filling material.

The present invention will be described in more detail through the following examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Test Example 1

After forming the norbornene polymer filler layer on the encapsulation substrate, it was bonded to the display substrate to produce a panel sample. The norbornene polymer filler layer had a thickness of 5 μm.

Test Example 2

Panel samples were prepared in the same manner as in Test Example 1, except that the thickness of the norbornene polymer filler layer was 10 μm.

Test Example 3

A panel sample was prepared in the same manner as in Test Example 1, except that nanopores having a particle diameter of 10 nm were formed in the filler.

Test Example 4

A panel sample was prepared in the same manner as in Test Example 2, except that nanopores having a particle diameter of 10 nm were formed in the filler.

Control Test Example 1

Panel samples were prepared in the same manner as in Test Example 1, except that no filler was used.

Control Test Example 2

A panel sample was prepared in the same manner as in Test Example 1, except that an epoxy polymer was used as a filler.

Control Test Example 3

A panel sample was prepared in the same manner as in Comparative Test Example 2, except that the thickness was 10 μm.

evaluation

The samples according to Test Examples 1 to 4 and Control Test Examples 1 to 3 were stored at 85°C/85% RH, and then turned on to observe the expression time of dark spots.

In addition, for samples according to Test Examples 1 to 4 and Control Test Examples 1 to 3, 10 g of SUS Ball was dropped from a predetermined height, and then the panel was observed for breakage.

Table 1 shows the results.

Test Example 1 Test Example 2 Test Example 3 Test Example 4 Control Test Example 1 Control Test Example 2 Control Test Example 3 Dark spot onset time
(h) 2000 2000 2000 2000 2000 1000 800 Evaluation of occurrence of defects in case of fall Bad when falling at 20cm Bad when falling at 30 cm Bad when falling at 20cm Bad when falling at 20cm Bad when falling at 5 cm Bad when falling at 15cm Bad when falling at 20cm

Referring to Table 1, all of the panels according to Test Examples 1 to 4 had a dark spot expression time of 2000 hours, whereas the panel according to Control Test Example 2 was 1000 hours, and the panel according to Control Test Example 3 was only 800 hours. It can be seen that the storage reliability is poor compared to Test Examples 1 to 4. In addition, the panels according to Test Examples 1 to 4 all failed at 20 cm, whereas the defects occurred at 5 cm and 15 cm when the panels according to Control Test Examples 1 and 2 fell, respectively. Compared to 4, it can be seen that the impact resistance is poor.

Although the preferred embodiments of the present invention have been described in detail above, the scope of rights of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

100: display substrate 110: base substrate
120: display unit 200: sealing substrate
300: filling material 400: sealing material
500: getter 600: coating layer
1000: display device

Claims (16)

Display Board,
An encapsulation substrate facing the display substrate,
A filling material positioned between the display substrate and the encapsulation substrate and comprising a norbornene-based resin, and
Sealing material to bond between the display substrate and the sealing substrate
Including,
The filling material further includes a nano-pore forming agent,
The nano pore formers are cyclic ester oligomers, linear ester oligomers, copolymers thereof, methyl methacrylate, hydroxyethyl methacrylate, dimethylamino ethyl methacrylate, ethylene oxide, propylene oxide, their oligomers and their Containing a copolymer,
The filling material is a display device having a thickness of 5μm to 10μm. In claim 1,
The norbornene-based resin is a display device including a cyclic olefin copolymer containing a norbornene-based monomer. In claim 1,
The filling material has a display device having pores. In claim 3,
The pore is a display device having a particle diameter of 1 nm to 10 nm. In claim 3,
The pore is a circular or oval display device. In claim 1,
The encapsulation substrate is a display device including aluminum (Al), copper (Cu), tungsten (W), alloys thereof, or a combination thereof. In claim 1,
And a getter positioned between the display substrate and the encapsulation substrate. In claim 1,
The display substrate
Base Substrate,
A pair of electrodes formed on the base substrate and facing each other, and
The organic emission layer interposed between the pair of electrodes
Display device comprising a. Preparing a filler using a norbornene-based resin,
Forming a porous thin film by applying the filler between the display substrate and the sealing substrate, and
Bonding the display substrate and the encapsulation substrate using a sealing material
Including,
The step of manufacturing the filler includes adding a nano pore former,
The nano pore formers are cyclic ester oligomers, linear ester oligomers, copolymers thereof, methyl methacrylate, hydroxyethyl methacrylate, dimethylamino ethyl methacrylate, ethylene oxide, propylene oxide, their oligomers and their Containing a copolymer,
The porous thin film is a method of manufacturing a display device having a thickness of 5μm to 10μm. In claim 9,
The norbornene-based resin is a manufacturing method of a display device comprising a cyclic olefin copolymer containing a norbornene-based monomer. In claim 9,
The step of forming the porous thin film is a step of heat treatment at 90°C to 200°C in the atmosphere after applying the filler, and
Step of heating to 250 ℃ to 400 ℃ under nitrogen atmosphere or vacuum
Method of manufacturing a display device comprising a. In claim 9,
The forming of the porous thin film may include applying the filler by a film attaching method or a liquid coating method. In claim 12,
The liquid coating method is a spin coating, screen printing, inkjet, ODF (one drop filling) or a method of manufacturing a display device performed by a combination thereof. In claim 9,
The porous thin film is a method of manufacturing a display device having pores. In claim 14,
The pores are round or oval manufacturing method of the display device. In claim 14,
The pores are a method of manufacturing a display device having a particle diameter of 1 nm to 10 nm.

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