KR20120055757A - Organic light emitting diode device and method for encapsulating the same - Google Patents

Abstract

PURPOSE: An organic light emitting diode display device and an encapsulation method thereof are provided to arrange a metal sheet on a thin film transistor substrate using a reel which includes a carrier film in which the metal sheet is attached, thereby improving productivity by simplifying an encapsulation process. CONSTITUTION: An array layer(120) which includes a wire, an organic light emitting device, and a thin film transistor is formed on the upper side of a transparent substrate(100). A plurality of metal sheets(300) is arranged using an arrangement apparatus(700) on the upper side of the array layer. The arrangement apparatus individually separates the plurality of metal sheets from a carrier film(610). The plurality of metal sheets includes an encapsulation film for sealing the array layer. The transparent substrate and the plurality of metal sheets are combined.

Description

Organic light emitting diode display device and encapsulation method {ORGANIC LIGHT EMITTING DIODE DEVICE AND METHOD FOR ENCAPSULATING THE SAME}

The present invention relates to an organic light emitting diode display and an encapsulation method, and more particularly, a metal sheet including an encapsulation film is attached to a carrier film, and each metal sheet is attached to a TFT substrate using a reel wound around the carrier film. The present invention relates to an organic light emitting diode display device and an encapsulation method for automating the encapsulation process of an organic light emitting diode display device by arranging to correspond to an OLED element on a transparent substrate) and bonding a metal sheet and a TFT substrate.

Recently, as the information society develops, the demand for the display field is increasing in various forms, and in response, various flat panel display devices, for example, liquid crystal, which have features such as thinning, light weight, and low power consumption Liquid crystal display devices, plasma display panels, organic light emitting diode devices, and the like are being studied.

An organic light emitting diode device (OLED device) is a display device that emits light by using an organic compound that emits red (R), green (G), and blue (B) light on a glass substrate. Generally includes an OLED panel and a driving circuit.

In the organic light emitting diode display, as the voltage is applied to the cathode and the anode, electrons and holes are respectively transferred from the cathode and the anode into the emission layer EML. It is a display device using the principle that the injected electrons and holes combine to generate excitons, and the generated excitons fall from the excited state to the ground state and emit light.

Therefore, unlike a liquid crystal display device, a separate light source is not required, and thus, a backlight unit is not required, and thus, a manufacturing process is simple. It is in the spotlight as the next-generation flat panel display device

In addition, the viewing angle and contrast ratio are superior to the liquid crystal display device. In addition, the organic light emitting diode display device is capable of driving a DC low voltage and uses a liquid crystal so that the response speed is fast and all solids are solid. Because of this, it is strong against external shocks and has a wide range of operating temperatures.

Meanwhile, the metal electrode of the organic light emitting diode display, that is, the cathode, uses a low work function material to improve electron injection characteristics, and the low work function material has a very high reactivity with moisture or oxygen. It is a material, and even organic compounds deposited on a substrate have a disadvantage of being very vulnerable to moisture and oxygen.

Therefore, when the organic light emitting device is exposed to moisture or oxygen, problems such as shortening of the device life may occur due to oxidation or peeling of the electrode material. An encapsulation process for sealing the light emitting element is required.

Hereinafter, a method of encapsulating an organic light emitting diode according to the related art will be described in detail.

1 is a schematic cross-sectional view of a conventional organic light emitting diode panel.

As shown in FIG. 1, the organic light emitting diode panel includes a transparent substrate 10 and an encapsulation sheet 30.

The transparent substrate 10 is mainly composed of glass, and an array layer 12 including a TFT, an organic light emitting element, and a wiring is formed thereon.

Here, the TFT may emit light as electrons and holes are injected into the emitting layer to generate excitons, and the generated excitons fall from the excited state to the ground state. To supply voltage to the organic light emitting device.

The organic light emitting device (OLED device) includes an organic thin film layer, and the organic thin film layer includes a hole injection layer (HIL), a hole transfer layer (HTL), an emitting material layer (EML), and an electron transport layer ( Electron Transfer Layer (ETL) and Electron Injection Layer (EIL) are formed by stacking sequentially.

The encapsulation sheet 30 is disposed on the organic light emitting diode, and may be glass or metal.

In addition, the encapsulation sheet 30 serves to protect the organic light emitting device from moisture and oxygen, and includes a moisture absorbent 20 to remove moisture.

Here, the moisture absorbent 20 may be CaO, BaO, silica gel, or the like.

Then, the adhesive sheet 40 is applied to the edge side surface of the encapsulation sheet 30 to bring the encapsulation sheet 30 into close contact with the transparent substrate 10. In this case, the adhesive resin 40 used may be a photocurable resin, a thermosetting resin, or the like, cured by light, heat, or the like.

2 is a view referred to explain a sealing process of a conventional organic light emitting device.

As shown in FIG. 2, the encapsulation process of a conventional organic light emitting device includes a plurality of metal sheets 30 for sealing a transparent substrate 10 on which an organic thin film layer is deposited, an array layer 12 (FIG. 1), and many of them. The tray 50 for bonding the metal sheet 30 of was used.

The metal sheet 30 is made of glass, soft plastic, film, or the like, and is cut into a predetermined size to seal the array layer (12 of FIG. 1) formed on the transparent substrate 100, and the encapsulation film 32. And a protective film 33.

Here, the encapsulation film 32 is a photocurable resin or a thermosetting resin that reacts with light and heat, and may be, for example, a pressure sensitive adhesive (PSA), which is a kind of an optically transparent adhesive film, and a protective film. 33 serves to protect the sealing film 32 (maintaining the adhesion of the sealing film 32).

A plurality of openings 51 are formed in the trays 50, and a plurality of metal sheets 30 are mounted in the plurality of openings 51, respectively, where the plurality of openings 51 of the tray 50 are formed. And a position (sealing position) for sealing the organic thin film layer of the transparent substrate 10.

By using the tray 50, a plurality of metal sheets 30 may be disposed at a position (sealing position) for sealing the organic thin film layer deposited on the transparent substrate 10.

3 is a flowchart illustrating a conventional method for encapsulating an organic light emitting device, and will be described with reference to FIG. 2.

As shown in FIG. 3, a plurality of metal sheets 300 are mounted in each of the plurality of openings 510 formed in the tray 500 (S100), and a protective film 330 from each of the plurality of metal sheets 300. To remove (S110).

Here, the metal sheet 300 is cut to a predetermined size to seal the array layer (12 in FIG. 1) formed on the upper side of the transparent substrate 100, and includes an encapsulation film 320 and a protective film 330. do. The predetermined size may be a size corresponding to that of the organic light emitting diode 110 because it is cut to a unit panel size.

Here, the plurality of openings 510 on which the plurality of metal sheets 300 are mounted are formed to correspond to a position (sealing position) for sealing the array layer (12 of FIG. 1) formed on the transparent substrate 100. .

Then, the transparent substrate 100, on which the organic thin film layer is deposited, and the plurality of metal sheets 300 are bonded to each other using a pressing device (S120), and the tray 500 is removed (S130).

As described above, since the conventional method for encapsulating the organic light emitting device uses a separate device called the tray 500, a process of attaching the metal sheet 300 to the tray 500 and a transparent substrate 100 having the organic thin film layer deposited thereon. After bonding the plurality of metal sheets 300 and there was a process of separating the tray 500.

In addition, a process of removing the protective film 330 after mounting the plurality of metal sheets 300 in each of the plurality of openings 510 of the tray 500 has been performed.

Therefore, the encapsulation process of the conventional organic light emitting device is complicated to process the organic light emitting device It was a factor of productivity inhibition.

The present invention is to solve the above problems, unlike the conventional method, the process of mounting a plurality of metal sheets in a tray (Tray), bonding a TFT substrate (transparent substrate) and a plurality of metal sheets (Metal Sheet) After removing the tray and removing the protective film from the metal sheet, the metal sheet is placed on the TFT substrate using a reel, and the TFT substrate (transparent substrate) and a plurality of metal sheets are removed. It is an object of the present invention to provide an organic light emitting diode display and a sealing method for improving productivity by simplifying and automating the encapsulation process of a film-type encapsulated organic light emitting device.

A method according to an embodiment of the present invention for achieving the above object comprises the steps of: forming an array layer including a TFT, an organic light emitting element, a wiring on an upper side of the transparent substrate; Disposing a plurality of metal sheets on the array layer; And bonding the transparent substrate and the plurality of metal sheets, wherein the plurality of metal sheets include an encapsulation film for sealing the array layer.

Here, the encapsulation film may be protected by the carrier film to which the plurality of metal sheets are attached.

The disposing of the metal sheet on the upper side of the array layer may include disposing the plurality of metal sheets to correspond to the array layer by using a reel wound around a carrier film. The encapsulation film may be protected by the carrier film attached thereto.

In addition, the radius of curvature of the reel is preferably set to maintain the elasticity of the plurality of metal sheets.

As described above, in the method of encapsulating the organic light emitting diode display device according to the present invention, since the carrier film also acts as a protective film as the metal sheet is attached to the carrier film, unlike the conventional method, the protective film is removed from the metal sheet during the encapsulation process. You can eliminate the process.

In addition, since the metal sheet is disposed on the TFT substrate by using a reel wound with a carrier film (carrier film with a metal sheet), the process of encapsulating the film type organic light emitting device can be simplified without using a tray.

In addition, since the reel wound around the carrier film (carrier film with a metal sheet) is used, the process can be automated, thereby improving the productivity of the film-type encapsulated organic light emitting device.

1 is a schematic cross-sectional view of a conventional organic light emitting device.
2 is a view referred to explain a sealing process of a conventional organic light emitting device.
3 is a flowchart illustrating a conventional method for encapsulating an organic light emitting device.
4 is a schematic view of an organic light emitting device.
5 is a schematic cross-sectional view of an organic light emitting diode panel according to a preferred embodiment of the present invention.
6A illustrates a reel in which a carrier film including a metal sheet according to an exemplary embodiment of the present invention is wound.
Figure 6b is a view showing a portion of a carrier film including a metal sheet according to a preferred embodiment of the present invention.
7 is a view referred to explain a method of encapsulating an organic light emitting device according to an exemplary embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

4 is a schematic view of an organic light emitting device.

As shown in FIG. 4, the organic light emitting diode is formed by sequentially stacking an anode 111, an organic thin film layer, and a cathode 117 on one surface of a substrate.

The anode 111 mainly uses indium tin oxide.

The organic thin film layer may include a hole injection layer (HIL) 112, a hole transfer layer (HTL) 113, an emitting material layer (EML) 114, and an electron transfer layer (Electron Transfer Layer). : ETL) 115, and Electron Injection Layer (EIL) 116, and are composed of organic compounds.

Here, the cathode 117 includes metals containing low work function components to improve electron injection characteristics, and the low work function metals include, for example, alkali metals such as lithium, magnesium, and the like. It may be the same alkaline earth metal.

When voltage is applied to the anode 111 and the cathode 117, holes and electrons are generated from the anode 111 and the cathode 117, respectively, in which the hole is a hole injection layer HIL. It is injected through the 112 and transported to the light emitting layer (EML) 114 through the hole transport layer (HTL) 113 easily, the electron (electron) is injected through the electron injection layer (EIL) 116 to the electron transport layer It is easily transported to the light emitting layer (EML) 114 through the (ETL) 115.

That is, the hole injection layer (HIL) 112 and the hole transport layer (HTL) 113 on the anode 111 facilitate the injection and transport of holes generated in the anode 111, the cathode 117 The electron injection layer (EIL) 116 and the electron transport layer (ETL) 115 under the) facilitate the injection and transport of electrons generated from the cathode 117.

As described above, in the organic light emitting diode display device, as the voltage is applied to the cathode 117 and the anode 111, electrons and holes are respectively emitted from the cathode 117 and the anode 111. 114) A display using the principle of being injected into the inside, the injected electrons and holes combine to generate excitons, and the generated excitons fall from the excited state to the ground state and emit light. Device.

At this time, the low work function metal used as the cathode 117 is a material having a very high reactivity with moisture or oxygen, and since the organic compound constituting the organic thin film layer deposited on the substrate is also very vulnerable to moisture and oxygen, the encapsulation process This is required, according to the present invention, it is possible to simplify and automate such a sealing process to improve the productivity of the organic light emitting device.

FIG. 5 is a schematic cross-sectional view of an organic light emitting diode panel according to a preferred embodiment of the present invention, and will be described with reference to FIG. 4.

As shown in FIG. 5, the organic light emitting diode panel includes a transparent substrate 100 and a metal sheet 300.

The transparent substrate 100 may be rigid or flexible, and may be made of glass, plastic, or the like, and an array layer 120 including TFT organic light emitting diodes and wirings is formed thereon.

Here, in the TFT, holes and electrons generated from the anode 111 and the cathode 117 are injected into the emission layer (EML) 114 to generate excitons, and generated excitons. It serves to supply a voltage to the organic light emitting element so as to emit light while falling from the excited state to the ground state.

The organic light emitting device (OLED device) includes an organic thin film layer.

The organic thin film layer may include a hole injection layer (HIL) 112, a hole transfer layer (HTL) 113, an emitting layer (EML) 114, and an electron transfer layer (Electron Transfer Layer). The ETL 115 and the electron injection layer EIL 116 may be stacked in this order.

The metal sheet 300 is spaced apart from the upper side of the array layer 120 to correspond to each array layer 120, and serves to protect the array layer 120 from moisture and oxygen.

In this case, the metal sheet 300 may be cut to a predetermined size in order to seal the array layer 120, and the predetermined size may be cut because the organic light emitting diode 110 is cut to a unit panel size. It may be of a corresponding size.

The metal sheet 300 includes an encapsulation film 320 for encapsulating the array layer 120, where the encapsulation film 320 is photocurable resin or thermosetting which is adhesive to light and heat. As the resin or the like, it may be, for example, an optically transparent adhesive film.

When the metal sheet 300 is used as the encapsulation sheet according to an embodiment of the present invention, strength may be further increased as compared with using an encapsulation sheet composed of conventional glass, soft plastic, and film.

Figure 6a is a view showing a reel (Reel) wound the carrier film comprising a metal sheet according to a preferred embodiment of the present invention, Figure 6b is a view of the carrier film comprising a metal sheet according to a preferred embodiment of the present invention It is a figure which shows a part.

As shown in FIGS. 6A and 6B, a carrier film 610 is wound around the reel 600, and a plurality of metal sheets 300 are mounted on the carrier film 610 spaced apart at regular intervals. .

The reel 600 also performs a function of storing and managing the carrier film 610 on which the plurality of metal sheets 300 are mounted, and the plurality of metal sheets 300 mounted on the carrier film 610 by using a placement apparatus. Also serves to be arranged in correspondence with a position (sealing position) for sealing the array layer 120 formed on the upper side of the transparent substrate 100.

The plurality of metal sheets 300 are cut to a predetermined size to seal the array layer 120 formed on the transparent substrate 100, and include an encapsulation film 320.

Here, the encapsulation film 320 may be, for example, PSA (Pressure Sensitive Adhesive), such as photocurable resin or thermosetting resin, which is adhesive to light and heat and is adhesive. The encapsulation film 320 may be attached to the carrier film 610.

Carrier film 610 according to the present invention, as well as the support for mounting a plurality of metal sheets 300 spaced apart at regular intervals through the adhesive sealing film 320, a plurality of encapsulation film of the metal sheet 300 Also serves as a protective film 330 to protect (320).

In the conventional encapsulation method, since a protective film (330 of FIG. 2) is attached to each encapsulation film 320 to protect the encapsulation film 320, the transparent substrate 100 and the plurality of metal sheets 300 are pressed using a pressing device. ), There was a process of separately removing the protective film 330 before bonding.

However, in the present invention, since the carrier film 610 protects the encapsulation film 320 by replacing the protective film 330, the process of separately removing the protective film 330 can be eliminated, thereby simplifying the process. The productivity of the organic light emitting device (OLED device) can be improved.

On the other hand, when winding the carrier film 610 on which the plurality of metal sheets 300 are mounted on the reel 600, there are a few points to note.

First, since each metal has its own elastic limit, it is necessary not to lose the elasticity of the plurality of metal sheets 300 when the carrier film 610 on which the plurality of metal sheets 300 are mounted is wound on the reel 600. There is.

In addition, the metal sheet 300 is cut to a predetermined size in order to seal the array layer 120, and in this case, it is necessary to cut the metal sheet 300 to the extent that the elasticity of the metal sheet 300 is not lost.

Here, elasticity is deformed when a load (external force) is applied to an object, and when the load is applied to a certain degree, the object recovers itself even if the load is removed. The limit at which an object can recover is called the elastic limit.

On the other hand, plasticity is a property in which deformation is permanently deformed even when the load is removed beyond the elastic limit, and plastic deformation is not permanently restored even when the load is removed due to the elastic limit. Say a variant.

When the metal part 310 of the metal sheet 300, for example, aluminum is wound with a certain force, bending deformation may occur according to the degree of winding. The smaller the radius of curvature of the aluminum, the longer the length of the aluminum deformation Easy to get up

That is, the conditions for the deformation may vary depending on the radius of curvature, thickness, and the like of aluminum.

Therefore, the radius of the reel (Reel) 600 according to the present invention is preferably set in the limit (limit that no bending deformation occurs) the elasticity of the plurality of metal sheet 300, which is the bending deformation occurs It can be determined experimentally by the radius of curvature of aluminum not.

When the carrier film 610 on which the plurality of metal sheets 300 are mounted is wound on the reel 600, the metal sheet 300 loses its elasticity and is plastically deformed due to a force applied thereto. When the array layer 120 is sealed by using the method, the surface of the metal sheet 300 may not be smooth, so that the array layer 120 may not be sealed, and defects may occur.

7 is a view referred to explain a method of encapsulating an organic light emitting device according to an exemplary embodiment of the present invention. This will be described with reference to Figs. 5, 6A and 6B.

The first figure shows a process of separating a plurality of metal sheets mounted on a carrier film) one by one using a placement device, and the second figure shows a process of arranging corresponding to an array layer on an upper side of a transparent substrate. The third figure shows the process of bonding together a number of metal sheets using pressurization equipment to closely adhere to the array layer.

As shown in FIG. 7, in the first picture, the plurality of metal sheets 300 mounted on the carrier film 610 wound on the reel 600 are separated one by one using the placement equipment 700, wherein the placement equipment ( 700 separates the plurality of metal sheets 300 from the carrier film 610 one by one by adsorbing metal portions (310 of FIG. 6B) of the plurality of metal sheets 300.

In the second figure, the arrangement device 700 is disposed on the upper side of the transparent substrate 100 so as to correspond to the array layer 120, wherein the encapsulation film 320 of the metal sheet 300 is It is disposed to face the array layer 120.

In addition, in the third figure, the transparent substrate 100 on which the plurality of metal sheets 300 are all disposed to correspond to the array layer 120 may be bonded using the pressing apparatus 800.

In the method of encapsulating the organic light emitting device according to the preferred embodiment of the present invention, the array layer 120 is formed on the upper side of the transparent substrate 100, and the array layer 120 is formed on the upper side of the formed array layer 120 to correspond to the array layer 120. The metal sheet 300 is disposed using the placement equipment 700.

Therefore, the process of removing the protective film 330 may be eliminated separately, and the process may be automated because the plurality of metal sheets 300 are moved by using the reel 600, thereby increasing the productivity of the organic light emitting device. Can be improved.

The embodiments of the present invention as described above are merely illustrative, and those skilled in the art can make modifications without departing from the gist of the present invention. Accordingly, the protection scope of the present invention includes modifications of the present invention within the scope of the appended claims and equivalents thereof.

Transparent substrate: 100 organic thin film layer: 110
Metal sheet: 300 Envelopes: 320
Tray: 500 Reels: 600
Carrier Film: 610

Claims (4)

Forming an array layer including a TFT, an organic light emitting element, and a wiring on an upper side of the transparent substrate;
Disposing a plurality of metal sheets on the array layer;
Bonding the transparent substrate and the plurality of metal sheets;
The plurality of metal sheets, the organic light emitting diode display device encapsulation method comprising a sealing film for sealing the array layer.
The method of claim 1,
The encapsulation film,
The method of encapsulating an organic light emitting diode display device, characterized in that protected by the carrier film attached to the plurality of metal sheets.
The method of claim 1,
Placing a plurality of metal sheets on the array layer,
And arranging the plurality of metal sheets so as to correspond to the array layer by using a reel wound around a carrier film.
The method of claim 3,
The radius of the reel (Reel),
And sealing the elasticity of the plurality of metal sheets.

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