KR20060002313A - Top-emission active matrix type organic light emitting display device and humidity-getter and polarizer film for the same - Google Patents

Abstract

A top emitting active organic EL display device is disclosed. In order for light generated in the organic light emitting layer to be emitted toward the opposite side of the TFT layer, a metal electrode is disposed on the TFT layer on the substrate, and the organic light emitting layer and the transparent electrode are sequentially stacked thereon. An insulating layer to a transparent electrode protective layer are interposed on the upper surface of the transparent electrode. Then, the transparent film and the circular polarizing film laminated film is placed thereon and sealed with a front transparent protective layer, or alternatively, only the transparent dehumidifying film is disposed on an insulating layer and sealed with a front transparent protective layer, Circular polarizing film is attached to the outer surface of the front transparent protective layer. The circular polarizing film has a structure in which a polarizing film and a quarter-wavelength (λ) retardation film are bonded to each other. The transparent dehumidifying film is made of a mixture containing a material having moisture removal properties and a thermoplastic polymer. Excellent light efficiency and simple manufacturing process.

Description

Top-emission active matrix type organic light emitting display device and humidity-getter and polarizer film for the same}

1 is a structural diagram of a back light emitting active organic light emitting display (OLED) device according to the prior art.

2 to 4 are cross-sectional views illustrating various structures of a top-emitting active organic EL display device constructed by applying a dehumidifying polarizing film in which a circular polarizing film and a transparent dehumidifying film are bonded according to an example of the present invention.

5 and 6 are cross-sectional views showing the structure of the circular polarizing film used in the present invention.

7 is a cross-sectional view illustrating a structure of a top-emitting active organic EL display device constructed by independently applying a circular polarizing film and a transparent dehumidifying film according to another example of the present invention.

* Description of the symbols for the main parts of the drawings *

11: front protective layer 12: opaque dehumidifying layer

13: insulation layer

14: metal electrode

15: organic light emitting unit 16: transparent electrode

17: TFT layer 18: back transparent protective layer

20,30,40: organic EL display element

21, 31, 41, 81: transparent front protective layer

22, 32, 44, 83: circularly polarizing film layer

23, 33, 43, 82: transparent dehumidifying layer

24, 84 (34, 45): insulating layer (transparent electrode protective layer)

25, 35, 46, 85: second electrode layer (transparent electrode)

26, 36, 47, 86: organic light emitting unit

27, 37, 48, and 87: first electrode layer (metal electrode)

28, 38, 490, 87: TFT layer

29, 39, 491, 89: back protective layer

51, 61: polarizing film

52, 54, 62: adhesive layer

53, 63: 1/4 wavelength retardation film

70, 72, 74: dehumidified polarizing film

The present invention relates to an organic light emitting display (OLED), and more particularly, to a structure of a front light emitting active organic display and a dehumidifying polarizing film suitable thereto.

The organic EL display device is widely used as a display device of various information industrial devices due to its high resolution, high impact resistance, and various colors. The display using the organic EL display device is much clearer than the liquid crystal display (LCD), the plasma display panel (PDP), the field emission display (FED), and there is no limitation of the viewing angle, High speed operation is possible and manufacturing cost is low. Therefore, it is attracting attention as a useful display that can be applied to a display panel of a TV or a computer or a mobile phone, a personal digital assistant (PDA), a computer, a television (TV), and a home appliance.

The organic EL display device can be largely classified into passive (active) and active (active). The passive organic EL display device has a disadvantage in that the manufacturing process is simple, but the driving voltage is high and the power is consumed a lot. The active OLED display device has advantages of lower driving voltage, lower power consumption, and a medium-large size screen than the passive type. 1 shows a structure of a conventional back light emitting active organic EL display device. An organic light emitting part 15 made of an organic EL material is interposed between the transparent electrode 16 disposed on the TFT layer 17 on the transparent protective layer 18 and the opaque metal electrode 14, and these are formed of an insulating layer ( 13) and an opaque dehumidifying layer 12 is disposed thereon, all of which are surrounded by a front protective layer 11. In the organic EL display device having such a structure, when a pair of electrodes facing each other, that is, the transparent electrode 16 and the metal electrode 14 supply electrons and holes to the organic light emitting unit 15, Electrons and holes combine to emit light within the organic light emitting material layer.

However, in the conventional active organic EL display device, as shown in FIG. 1, since a thin film transistor (TFT) 17 is disposed toward the substrate 18 from which light is emitted, part of the emitted light is partially. Has a disadvantage in that the light efficiency and aperture ratio of the TFT 17 are reduced. The disadvantage that the luminous efficiency is lowered due to the presence of the TFT is that the light generated from the organic light emitting unit 15 is emitted to the opposite side of the substrate 18 on which the TFT 17 is disposed, that is, to the front surface of the organic EL display element. Taking a top-emission scheme can be effectively overcome.

However, when constituting the front-emitting active organic EL display device, a dehumidifying agent, which is an essential component of the organic EL display device, must be disposed on the opposite side of the TFT substrate, and thus, a transparent dehumidifying agent having excellent light transmittance is required, and a new search for an appropriate arrangement method is required. Do. In addition, in order to realize good image quality of the display using the organic EL display device, it is necessary to remove the optical interference caused by the reflected light of the light introduced into the organic EL display device from the outside. As a means for this, a circularly polarized film (film having a polarizing function and a retardation function) needs to be disposed at an appropriate position between the organic light emitting portion and the viewer.

The present invention relates to a top-emitting organic EL display, and US Patent No. 5,739,545 discloses an organic EL display having a structure in which a transparent electrode is disposed on a front surface to extract light emitted from the organic light emitting layer to the front, but is an essential component of the organic EL display. The arrangement and composition of the dehumidifying agent is not mentioned.

Japanese Laid-Open Patent Publication No. 2003-144830 discloses an organometallic compound composed of a Group 3 metal and an organic terminal molecule as a transparent dehumidifying agent used for a front-emitting organic EL display. However, in order to arrange the transparent dehumidifier thin film inside the organic EL display, there are disadvantages in that process discomfort must be used and light is scattered because cracks are easily generated in the formed dehumidifier thin film. In addition, the contents regarding the arrangement of the polarizing film are not described. Moreover, the baking process which volatilizes a solvent is needed. Process to handle chemical solution and volatilize solvent, which can lead to environmental management problems in the workplace, and smooth surface of transparent dehumidification layer can bring uniform transmittance overall. Do. In addition, since several processes, such as a transparent absorption stock solution combination process, an application process, and a firing process, are required in the manufacturing process of the organic EL display, the process time increases. In particular, if the firing process is not perfected, the possibility of progressive dark spots is increased due to outgases such as internal residual solvent.

U.S. Patent No. 6,515,428, U.S. Patent 6,670,772, U.S. Patent No. 6,608,283 disclose the structure of the thin film transistor, the structure of the electrode, and the like with respect to the structure and manufacturing method of the front-emitting active organic EL display. The contents regarding the configuration, arrangement and the like of the polarizing film are not described.

U.S. Patent No. 5,714,838 and U.S. Patent No. 6,420,031 describe a transparent electrode for taking the form of front emission, but do not describe a transparent dehumidifying agent and a circular polarizing film.

U.S. Patent Nos. 5,920,080, 6,268,695 and 6,497,598 disclose a method of forming a protective layer by coating a plurality of layers of an insulating material having a low moisture permeability on a transparent electrode. However, there is a problem that the process of forming a plurality of layers of the protective layer is complicated and time-consuming, and the countermeasure against water flowing from the side of the protective layer is insufficient. In addition, the content regarding a circularly polarizing film is not described.

US Patent No. 6,703,184 discloses a method of using a transparent film having a low moisture permeability and a transparent film for the purpose of protecting the organic light emitting layer and the electrode. The disadvantage of insufficient measures against moisture introduced into the organic EL display during the manufacturing process is insufficient. There is this. In fact, the moisture flowing after sealing among the moisture that may exist inside the organic EL display may be blocked, but the moisture introduced by the material during the manufacturing process may not be removed.

An object of the present invention is that the light produced by the organic light emitting layer is emitted toward the front surface of the substrate on which the TFT (thin film transistor) is arranged, so that no light blocking phenomenon is caused by the TFT, and thus the light efficiency is higher than that of the organic EL display device of the conventional back-emitting type. It is to provide a much higher front emitting active organic EL display device.                         

Another object of the present invention is to provide a top-emitting active organic EL display device having a structure capable of adding a transparent dehumidifying film and a circular polarizing film in a very simple process.

Another object of the present invention is a bonding of a transparent dehumidifying film suitable for application to a front light emitting active organic EL display device and a circularly polarized film which prevents reflection of external light by an organic EL display device unit having high transparency and excellent water removal ability. To provide a film.

According to an aspect of the present invention for achieving the above object, there is provided a front-emitting active organic EL display device. The following two construction methods are possible depending on whether the transparent dehumidifying film and the circular polarizing film are integrally bonded and used in the form of a laminated film or in a non-bonded form.

First, according to the first configuration, the front light emitting active organic EL display device has a structure in which a TFT layer, a first electrode layer on which a plurality of electrodes are disposed, an organic light emitting layer, and a second electrode layer on which a plurality of transparent electrodes are arranged on a substrate are sequentially stacked. Organic EL display element portion formed of; A transparent insulating layer disposed on the transparent electrode; And a laminated film of a circularly polarized film that prevents external light from being reflected by the organic EL display element and a transparent dehumidified film that removes moisture from surroundings, comprising a dehumidified polarizing film layer disposed on the insulating layer. It is characterized by. The organic EL display device of this type is a means for protecting the above configuration more securely, and is made of a transparent material, and the inlet portion comes into contact with the substrate to provide an enclosed interior space, and the stacked structure on the substrate It is desirable to further include a front transparent protective layer which allows the components to be embedded and isolated from the outside. Furthermore, an insulating layer may be further interposed between the dehumidifying polarizing film layer and the front transparent protective layer.

According to the second configuration, the front light emitting active organic EL display device is formed of a structure in which a TFT layer, a first electrode layer having a plurality of electrodes disposed thereon, an organic light emitting layer, and a second electrode layer having a plurality of transparent electrodes disposed on the substrate are stacked in this order. Organic EL display element; A transparent insulating layer disposed on the transparent electrode; A transparent dehumidification film layer disposed on the insulating layer and transparent to remove surrounding moisture; A front transparent protective layer made of a transparent material and having an inlet part in contact with the substrate to provide an enclosed interior space, wherein the components stacked on the substrate are embedded in the interior space to be isolated from the outside; And a circularly polarized film layer attached to an outer surface of the front transparent protective layer and preventing external light from being reflected by the organic EL display device unit.

In the above two configuration methods, since the light emitted from the organic light emitting layer is emitted toward the opposite side of the TFT layer (front side of the device), the first electrode layer is composed of a metal electrode, as opposed to the back light emitting method. Is disposed toward the substrate on which the TFT layer is disposed, and the second electrode layer composed of a transparent electrode is disposed on the opposite side of the substrate on which the TFT layer is disposed (i.e., the front side of the element). Furthermore, the dehumidification film, the insulating layer, and the front protective layer disposed on the light exit path are made of a transparent material having good light transmission. As a result, the top emission type organic EL display device of the present invention is superior in light efficiency as compared to the conventional bottom emission type device. In addition, since the circular polarizing film is disposed between the observer and the organic EL display element unit to prevent the organic EL display element from reflecting external light, there is no problem of deterioration in image quality due to optical interference.

 In addition, in the case of the first configuration method, since the transparent dehumidifying agent and the circular polarizing film are first manufactured as a laminated film in a separate process, the laminated film is introduced into the organic EL display manufacturing process, and thus, a simple method is applied to the outside of the transparent electrode. Since it can be arranged, the attaching process is simple and the thickness of the bonding film is thick, so that the attaching yield is good.

On the other hand, according to another aspect of the present invention, there is provided a dehumidifying polarizing film that can be used for the front-emitting active organic EL display device of the first configuration. The dehumidifying polarizing film has a structure in which a circular polarizing film and a transparent dehumidifying film are bonded to each other, and provides a function of dehumidifying and blocking the light emitted from the outside from being reflected back. The circular polarizing film has a structure in which a polarizing film and a quarter-wavelength (λ) retardation film are bonded to each other, and allows the transmission of the polarization component of the external incident light, but reflects the polarization component reflected by the organic EL display element. Is not allowed to pass through. The transparent dehumidifying film is made of a mixture including a material having water removal properties and a thermoplastic polymer, and the material having water removal properties includes organo metal compounds, metal hydrides, and metals. At least one selected from the group consisting of metal oxides and mixtures thereof. Furthermore, it is preferable that the thermoplastic polymer satisfies a water transmittance (MVTR) at 40 ° C. and 75% RH (relative humidity) of 100 g · mil / m ² · day or more. Materials that can be used as the thermoplastic polymer can be selected from the group consisting of polystyrene, polybutadiene, polyisoprene, polyolefins, thermoplastic copolymers including one or more thereof, and mixtures thereof.

Hereinafter, with reference to the accompanying drawings will be described the present invention in more detail.

Various possible structures of the organic EL display device according to the invention are shown in FIGS. 2 to 4. For reference, hatched portions indicate opaque layers, vertical shaded portions indicate transparent or opaque layers, and unpatterned portions indicate transparent layers.

The basic structure of an organic EL display device is usually a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL). And an electron injection layer (EIL), and if necessary, a hole blocking layer may be further disposed between the light emitting layer and the electron transport layer. Also in this invention, this basic structure is employ | adopted as it is. However, in consideration of the light emission path of the organic light emitting layer, it is only necessary to further consider the arrangement position of the transparent electrode.

As illustrated in FIGS. 2 to 4, the organic EL display device proposed by the present invention has the organic EL display device units 20, 30, and 40 having a common structure. That is, the organic EL display element units 20, 30, and 40 may include the first electrode layers 27, 37, and 48 having a plurality of electrodes disposed on the TFT substrates 28, 38, and 490, and an organic light emitting layer made of an organic light emitting material ( 26, 36, 47, and the second electrode layers 25, 35, and 46 on which a plurality of electrodes are arranged are sequentially stacked. The organic EL display element portions 20, 30, and 40 have TFT substrates 28, 38, and 490 disposed on the rear protective layers 29, 39, and 491, and thus transparent second electrode layers 25, 35, and 46. Is placed on the front. As is well known, the organic light emitting layers 26, 36, and 47 emit light by transporting and recombining holes and electrons supplied from the first electrode layers 27, 37, and 48 and the second electrode layers 27, 37, and 48. Is made with. In order for the light emitted from the organic light emitting layers 26, 36, and 47 to emit light to the entire surface, the first electrode layers 27, 37, and 48 do not have to be transparent, and thus the second electrode layer 27 may be made of an opaque metal electrode. , 37, 48 should be composed of a transparent electrode so that the light generated from the organic light emitting layer (26, 36, 47) can be transmitted. An example of the transparent electrode may be an indium tin oxide (ITO) electrode.

The insulating layers 24, 34, 45 are disposed on the organic EL display element units 20, 30, and 40 having such a structure, and the transparent dehumidifying film layers 23, 33, 43, and the circular polarizing film layers 22 are disposed thereon. Films 70, 72, 74, hereinafter referred to as " dehumidified polarizing film "

The plurality of electrodes of the transparent electrode layers 27, 37, and 48 are insulated from each other. In this state, when the transparent dehumidifying film layers 23, 33, 43 or the circular polarizing film layers 22, 32, 44 are laminated on the transparent electrode layers 27, 37, and 48 in direct contact, the transparent dehumidifying film layer ( Moisture or the like contained in 23, 33, 43 interferes with the insulation between the electrodes of the transparent electrode layers 27, 37, and 48, and in severe cases, a short circuit occurs between the electrodes. In order to prevent short circuits between the transparent electrodes, the organic EL display device units 20, 30, and 40 are interposed between the insulating layers 24, 34, and 45 between the dehumidifying polarizing films 70, 72, and 74. Good insulation is maintained between the electrodes of the electrode layers 27, 37, and 48. The insulating layers 24, 34, 45 are preferably made of a material having high electrical resistance and excellent transparency. The state of the material used for the insulating layers 24, 34, 45 may be any state of solid, liquid or gas. Argon gas or nitrogen gas in the case of gas, silicon oil in the case of liquid, and polymer or glass material in the case of a solid are examples of materials that may be used as the insulating layers 24, 34, and 45. For reference, the insulating layer 24 of FIG. 2 is a gas or liquid insulating layer, and FIGS. 3 and 4 are solid insulating layers. In particular, the solid insulating layer has a physical function for the transparent electrode layers 35 and 46 in addition to the insulating function. It also has the function of a phosphorus protective layer.

With the dehumidified polarizing film layers 70, 72, and 74 added, the front protective layers 29, 39, 491 cover the front and side surfaces with the cap-shaped front transparent protective layers 21, 31, and 41, and The interface of is sealed with a sealant (not shown) and sealed. In this case, as shown in FIG. 2, the insulating layer 24 is interposed between the front transparent protective layer 21, the dehumidifying polarizing film layer 70 and the organic EL display element unit 20 therein, or FIG. As shown in Fig. 4, another insulating layer 42 may be interposed between the front transparent protective layer 41, the dehumidifying polarizing film layer 74 and the organic EL display element unit 40 therein. The front transparent protective layers 21, 31 and 41 may be made of, for example, transparent glass or a polymer film. In the structure as shown in FIG. 3, since the circular polarizing film layer 32 has a certain thickness and also has a protective function, the front transparent protective layer 31 is not necessarily required.

In arranging the dehumidifying polarizing film layers 70, 72, and 74, any of the transparent dehumidifying film layers 23, 33, and 43 and the circular polarizing film layers 22, 32, and 44 may be a second electrode layer, that is, a transparent electrode layer ( 27, 37, 48) may be disposed toward. However, the transparent dehumidifying film layers 23, 33, 43 are preferably made to be close to the gas insulating layer 24 or 42 when the insulating layer is composed of gas, and the insulating layer is composed of solid (in case of FIG. 3). It is preferable to arrange close to the transparent electrode 35. In addition, the transparent dehumidifying film layers 23, 33, 43 are preferably separated from the other layers except the circularly polarizing film layers 22, 32, 44 by the insulating layers 23, 34, 42.

Circular polarizing film used in the present invention is a laminate of a film having a polarizing function that transmits only the polarization component of the incident light and a film having a phase difference function to produce a phase difference between the incident light and the transmitted light by 1/4 wavelength (λ) ' 5 'and 6' represent a representative structure. It is based on the structure which the polarizing films 51 and 61 and the quarter wavelength ((lambda)) retardation films 53 and 63 were adhere | attached with the adhesive bond layers 52 and 62, and the quarter wavelength retardation film 53 as needed. The adhesive layer 54 can be further added to (). The organic EL display element unit 20, 30, 40, wherein the polarization component of the external light passing through the polarizing films 51 and 61 from the outside serves as a pass-> reflective portion of the 1/4 wavelength retardation film 53 or 63. The polarization direction is rotated by 90 ° C. while passing through the optical path of 'reflection-> 1/4 wavelength retardation films 53 and 63', thereby preventing the polarization films 51 and 61 from passing through. The circular polarizing film prevents external light from being reflected by the organic EL display element units 20, 30, and 40, and thus optical interference between the external light and light generated in the organic light emitting layers 26, 36, and 47 is prevented. Do not happen. Therefore, people cannot see the external light reflected by the organic EL display element units 20, 30, and 40, and only the light of the organic light emitting layers 26, 36, and 47 can be seen.

The transparent dehumidifying agent, which is a raw material of the transparent dehumidifying film layers 23, 33, and 43, should have good dehumidification performance, be easily formed into a film form, have transparent properties after film forming, and be easily bonded to circular polarizing films. shall. Mixtures comprising materials having moisture removal properties (hereinafter referred to as 'moisture removal agents') and thermoplastic polymers satisfy these properties well. Therefore, this mixture is used to make a transparent dehumidifying film. The moisture removing agent is at least one selected from the group consisting of organo metal compounds, metal hydrides, metals, metal oxides, or mixtures thereof. In order to process the moisture remover in the form of a film, a binder for the raw material of the moisture remover is required, and the thermoplastic polymer is included as the binder.

The organo metal compounds that can be used as the water removing agent for the transparent dehumidifying film of the present invention is preferably selected from the compounds represented by the following [Formula 1] or mixtures thereof.

[Me-R _m R ' _n ] _x

Wherein Me is one or two or more of the same or different metals selected from the group consisting of alkali metals, alkaline earth metals, aluminum, titanium, zirconium, and silicon,

R is any one selected from the group consisting of a saturated or unsaturated alkyl group, a saturated or unsaturated aryl group, a saturated or unsaturated alkyloxy group, and a saturated or unsaturated allyloxy group,

R ′ is any one selected from the group consisting of hydrogen, saturated or unsaturated alkyl groups, saturated or unsaturated aryl groups, saturated or unsaturated alkyloxy groups, and saturated or unsaturated allyloxy groups,

m and n are each an integer of 0 ≦ m or n ≦ 4, the sum of these m + n is 1 ≦ m + n ≦ 4, and x is an integer greater than 1 or 1.

For example, the mechanism by which water is removed by sodium pentoxide and sodium bis (2-methoxyethoxy) aluminum hydride among organometallic compounds is shown in Scheme 1 and Scheme 2, respectively.

CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ O-Na + H ₂ O → CH ₂ CH ₂ CH ₂ CH ₂ CH ₃ OH + NaOH

[(CH ₃ OC ₂ H ₄ O) ₂ AlH ₂ ] Na + 4H ₂ O → 2CH ₃ OC ₂ H ₄ OH + Al (OH) ₃ + NaOH + 2H ₂

Metal hydrides which can be used as water scavengers for transparent dehumidifying films are alkali metal hydrides including alkali metal hydrides, alkaline earth metal hydrides, boron or aluminum (for example, 'alkali'Metals' and 'boron / aluminum' materials, such as LiBH ₄ or LiAlH ₄ and the like, alkaline earth metal hydrides including boron (Boron) or aluminum (for example, 'alkaline metal' and such that the material that is to have as a "boron / aluminum", CaB ₂ H ₈ or CaAl ₂ H _8), and is preferably selected from the group consisting of a mixture thereof. In the case of the water remover using the metal hydride, water is removed by the following scheme 3.

MH _n + nH ₂ O → M (OH) _n + nH ₂

The metal used as the moisture remover is preferably selected from the group consisting of metals having a higher ionization tendency than hydrogen or mixtures of such metals. Examples of such metals are alkali metals, alkaline earth metals, aluminum, nickel, iron, zinc and the like.

In addition, the metal oxide (metal oxide) used as a moisture removal agent is preferably selected from the group consisting of alkali metal oxides, alkaline earth metal oxides or mixtures thereof.

On the other hand, the thermoplastic polymer is preferably made of a polymer having a high moisture vapor transmission rate (MVTR) because the light transmittance is reduced when the porous polymer is produced in a porous manner so that material transfer occurs smoothly. In addition, it is desirable to minimize turbidity in order to minimize the decrease in transmittance due to light scattering. Furthermore, it is desirable to have a property that the dehumidifier film can be attached to another object (for example, a circularly polarized film) by heating and pressing without a separate adhesive.

In order to reduce the turbidity of the mixture of the water scavenger and the thermoplastic polymer, it is preferable that the water scavenger and the thermoplastic polymer have the following characteristics.

(1) the particle size of the moisture scavenger is sufficiently smaller than the wavelength of visible light (usually 50 nanometers or less) and is in the Rayleigh scattering range,

(2) It is preferable that the Rayleigh ratio (R (theta)) defined by the following Equation 1 is small because the refractive index of the moisture removing agent and the polymer is similar. In other words,

Here, n ₀ is a refractive index of the thermoplastic polymer and has a specific range of values inherent to each material, and c is a concentration of the moisture removing agent, but it cannot be lowered below a certain concentration in consideration of the water removing efficiency of the transparent dehumidifying agent. In addition, λ has a constant value because it is the wavelength of visible light, M and N _A is also a constant value because the molecular weight and avogadro number of the water scavenger, respectively. Therefore, a way to lower the Rayleigh ratio is to make the value ' dn / dc ' small. ' dn / dc ' is the amount of change in the refractive index of the mixture of the water scavenger and the thermoplastic polymer according to the concentration change.

MVTR may vary somewhat depending on the processing method of the film but is a physical property depending on the chemical structure of the thermoplastic polymer. Therefore, MVTR is a property that can be used as a selection criterion of the thermoplastic polymer used as a mixed material with the water removing agent in the present invention. In the present invention, the thermoplastic polymer used as a mixed material with the moisture removing material is preferably a substance having a MVTR of 100 g · mil / m ² · day or more at 40 ° C. and 75% RH (relative humidity). The material that satisfies these properties is at least one selected from the group consisting of polystyrene, polybutadiene, polyisoprene, polyolefins, thermoplastic copolymers comprising one or more thereof, and mixtures thereof.

On the other hand, the dehumidifying polarizing film bonded to the circular polarizing film and the transparent dehumidifying film is manufactured by the following method.

(1) The thermoplastic polymer having a double bond with the selected chemical moisture remover is melted by heating or dissolved in a solvent to obtain a transparent dehumidifying agent.

(2) The transparent dehumidifying agent is formed into a film by using a calender roll apparatus or the like.

(3) The molded transparent dehumidifying film is bonded to the circular polarizing film by heat pressing or by using an adhesive. This process may be performed simultaneously with the process of (2).

In this way, if a laminated film of a circular polarizing film and a transparent dehumidifying film, that is, a dehumidifying polarizing film, is obtained, the dehumidifying polarizing film is dried to a predetermined size and then thermally or high frequency is used or an adhesive is used as an organic EL display as described above. It adhere | attaches to the required position outside the transparent electrode 25, 35, 46 of the element part 20, 30, 40. FIG. Finally, the organic EL display element is sealed. As illustrated in FIGS. 2 to 4, the adhesion position of the dehumidifying polarizing film may vary according to the method of constructing the organic EL display device.

If necessary, a substance that absorbs hydrogen, a substance that reacts with hydrogen, or a substance that promotes the reaction with hydrogen may be added to the transparent dehumidifying agent. In addition, after the molding of the transparent dehumidifying film is finished or after the bonding of the film is completed, the thermoplastic polymer blended in the transparent dehumidifying agent may be crosslinked and used.

On the other hand, the circular polarizing film and the transparent dehumidifying film does not always need to be used in the form of a laminated film. The functional dehumidification film must be located inside the front transparent protective layer, but the circular polarizing film may be disposed on the outer surface of the front transparent protective layer. Therefore, the structure of FIGS. 2 to 4 is modified, and as shown in FIG. 7, the back protective layer 89, the TFT substrate 88, the first electrode layer 87, the organic light emitting layer 86, and the second electrode layer 86 ) Is laminated in this order and the insulating layer 84 is interposed therebetween, and then the transparent dehumidifying film 82 is adhered to the inner surface of the front transparent protective layer 81, and the circular polarizing film layer 83 is the front transparent protective layer. It can also be made into a structure bonded to the outer surface of (81).

However, this structure can be more complicated compared to the structure of Figures 2 to 4 and in particular the adhesion yield of the film can be lowered. The thickness of the laminated film of these two films is thicker than that of each of the circularly polarized film and the transparent dehumidifying film. Therefore, the structure of FIG. 7 may cause more problems such as tearing or incomplete adhesion during the film attaching process. In addition, the process of bonding the two films to each other is very simple, while the process of attaching the film to the front transparent protective layer is not simple considering the structure of FIG. It is relatively more complicated.

<Example 1-8>

(1) Sample preparation

Samples of 20 dehumidified polarizing films (bonded film of circular polarizing film layer and transparent dehumidifying film layer) were prepared in the method shown in Table 1 in a glove box kept at 1 ppm or less (in Example 1-4). At the same time, 20 samples of the circularly polarized film and the transparent dehumidifying film which are not bonded to each other were produced (corresponding to Example 5-8).

After mixing the moisture removal agent and the polymer as described in Table 1, it was processed into a flexible film form of 20 micrometers thick by extrusion and calendering. All the 'moisture removers' used in the preparation of the samples were used by grinding to a size of 50nm or less using a high energy mill.

division Substances that react with water (moisture remover) Polymers with double bonds Substance weight% Substance weight% Example 1 Example 5 Sodium bis (2-methoxyethoxy) aluminum hydride [(CH ₃ OC ₂ H ₄ O) ₂ AlH ₂ ] Na 20 Polystyrene-Polyisoprene-Polystyrene Block Copolymer 80 Example 2 Example 6 Calcium Hydride CaH ₂ 20 Polystyrene-Polyisoprene-Polystyrene Block Copolymer 80 Example 3 Example 7 Sodium Na 20 Polybutadiene-Polystyrene-Copolymer 80 Example 4 Example 8 Calcium Oxide CaO 20 Polybutadiene-Polystyrene-Copolymer 80

(2) Assembling and evaluating light transmittance of front-emitting active organic EL display

0.8 mm thick using the prepared circularly polarizing film and the transparent dehumidifying film prepared as described in Table 1 as the front transparent protective layer (21, 31, 41, 81) of the front-emitting active organic EL display by the method described in Table 2. It was attached to the transparent glass cap of the light emitting active organic EL display device. The light transmittance was measured by irradiating light having a wavelength of 550 nm to the organic EL display device, and the results are shown in Table 3.

division Example 1-4 Example 5-8 Attachment method The transparent dehumidifying film and the circular polarizing film were heat-bonded to prepare one film (dehumidifying polarizing film), and then attached to the inside of the transparent glass cap of the organic EL display device. Example 1 and Example 2 were attached as shown in FIG. 2, Example 3 as shown in FIG. 3, Example 4 as shown in FIG. As illustrated in FIG. 7, the transparent dehumidifying film was attached to the inner surface of the transparent glass cap of the organic EL display, and the circularly polarized film was attached to the outer surface of the transparent glass cap.

division Example 1 Example 2 Example 3 Example 4 Light transmittance 41% 40% 38% 42% Adhesion yield 20/20 20/20 20/20 20/20 division Example 5 Example 6 Example 7 Example 8 Light transmittance 43% 41% 40% 43% Adhesion yield 7/20 7/20 9/20 10/20

Here, the adhesion yield indicates the degree to which the film is successfully attached when the transparent dehumidifying film and the circular polarizing film are attached to the inside or the inner surface or the outer surface of the transparent glass cap.

(3) Water removal function evaluation

In addition, the organic EL device manufactured through the above process was stored at a temperature of 50 ^° C. and a relative humidity of 90% for 200 hours, and the results of measuring the moisture concentration inside the organic light emitting device are shown in Table 4 below. . For reference, Example 5-8 was not significantly different from Example 1-4.

division Example 1 (Example 5) Example 2 (Example 6) Example 3 (Example 7) Example 4 (Example 8) Moisture concentration (ppm) 20 or less below 10 below 10 20 or less

Since the manufacturing process as in Example 1-4 is bonded to the organic EL display after the transparent dehumidifying film and the circular polarizing film in a separate process, the assembly process of the organic EL display is very simple, due to the bonding of the film The thickness became thicker and the yield of adhesion appeared. On the other hand, in Example 5-8, two bonding processes are required, and in particular, a process of attaching the transparent dehumidifying film having a thickness of 20 micrometers to the transparent protective layer has a high failure rate. In order to make the organic EL display device of the structure of Figure 7 requires a separate measure to increase the adhesion yield.

In terms of light transmittance, the case of Example 1-4 was 1 to 3% lower than that of Example 5-8, but the difference was difficult to distinguish by visual observation.

The organic EL display device according to the present invention takes the form of front light emission, so that no light blocking phenomenon is caused by the TFT (thin film transistor), and thus the light efficiency is much higher than that of the organic EL display device of the conventional back light emission type.

In addition, since the circularly polarizing film is disposed on the light emitting path of the organic EL display element portion, external light reflection by the organic EL display element portion does not occur, and thus the quality degradation of the display screen due to interference between the light of the organic light emitting layer and external light does not occur. Do not.

Furthermore, the front light-emitting active organic EL display device proposed by the present invention has a simple manufacturing process (especially in the case of Examples 1-4), maintains transparency at a certain level, and even in harsh moisture penetration conditions. The moisture of can be kept low enough.

Claims (21)

An organic EL display element unit having a structure in which a TFT layer, a first electrode layer on which a plurality of electrodes are disposed, an organic light emitting layer, and a second electrode layer on which a plurality of transparent electrodes are disposed are sequentially stacked; A transparent insulating layer disposed on the transparent electrode; And A laminated film of a circular polarizing film that prevents external light from being reflected by the organic EL display element and a transparent dehumidifying film that removes ambient moisture, comprising a dehumidifying polarizing film layer disposed on the insulating layer. A front-emitting active organic EL display device. An organic EL display element unit having a structure in which a TFT layer, a first electrode layer on which a plurality of electrodes are disposed, an organic light emitting layer, and a second electrode layer on which a plurality of transparent electrodes are disposed are sequentially stacked; A transparent insulating layer disposed on the transparent electrode; A bonding film of a circularly polarized film that prevents external light from being reflected by the organic EL display device unit and a transparent dehumidifying film that removes ambient moisture, the dehumidified polarizing film layer disposed on the insulating layer; And It is made of a transparent material, the inlet portion is in contact with the substrate to provide a closed inner space, and further comprising a front transparent protective layer to the interior space and the components stacked on the substrate is embedded to be isolated from the outside A front-emitting active organic EL display device. An organic EL display element unit having a structure in which a TFT layer, a first electrode layer on which a plurality of electrodes are disposed, an organic light emitting layer, and a second electrode layer on which a plurality of transparent electrodes are disposed are sequentially stacked; A transparent insulating layer disposed on the transparent electrode; A transparent dehumidification film layer disposed on the insulating layer and transparent to remove surrounding moisture; A front transparent protective layer made of a transparent material and having an inlet part in contact with the substrate to provide an enclosed interior space, wherein the components stacked on the substrate are embedded in the interior space to be isolated from the outside; And And a circularly polarized film layer attached to an outer surface of the front transparent protective layer and preventing external light from being reflected by the organic EL display element unit. The material of any one of claims 1 to 3, wherein the insulating layer may be a material in any state of a solid, liquid, or gas, and is made of a material having sufficient insulation to ensure insulation between the plurality of transparent electrodes. Full-emitting active organic EL display device, characterized in that. The front light emitting active organic EL display device according to claim 2, wherein the circular polarizing film of the dehumidifying polarizing film layer is directly attached to an inner surface of the front transparent protective layer. The front light emitting active organic EL display device according to claim 2, wherein an insulating layer is further interposed between the dehumidifying polarizing film layer and the front transparent protective layer.        The method of any one of claims 1, 2, 3, 5, and 6, wherein the transparent dehumidifying film layer comprises a material having a light transmittance and a water removal property and a thermoplastic polymer, the material having a water removal property is an organometallic compound (organo metal compounds), metal hydrides (metal hydrides), at least one selected from the group consisting of a metal (metal oxide) or a mixture thereof. device. The device of claim 7, wherein the organometallic compound is selected from a compound represented by the following [Formula 1] or a mixture thereof. [Formula 1] [Me-R _m R ' _n ] _x In Formula 1, Me is one or two or more of the same or different metals selected from the group consisting of alkali metals, alkaline earth metals, aluminum, titanium, zirconium, and silicon, R is any one selected from the group consisting of a saturated or unsaturated alkyl group, a saturated or unsaturated aryl group, a saturated or unsaturated alkyloxy group, and a saturated or unsaturated allyloxy group, R ′ is any one selected from the group consisting of hydrogen, saturated or unsaturated alkyl groups, saturated or unsaturated aryl groups, saturated or unsaturated alkyloxy groups, and saturated or unsaturated allyloxy groups, m and n are each an integer of 0 ≦ m or n ≦ 4, and the sum thereof m + n is 1 ≦ m + n ≦ 4, x is 1 or an integer greater than 1. 8. The metal hydride of claim 7, wherein the metal hydride is an alkali metal hydride, an alkaline earth metal hydride, an alkali metal hydride including boron or aluminum, an alkaline earth metal hydride including boron or aluminum, and A light emitting active organic EL display device, characterized in that any one selected from the group consisting of a mixture thereof.        The front light-emitting active organic EL display device according to claim 7, wherein the metal is selected from the group consisting of a metal having a higher ionization tendency than hydrogen or a mixture thereof.        The front light emitting active organic EL display device according to claim 7, wherein the metal oxide is selected from the group consisting of alkali metal oxides, alkaline earth metal oxides or mixtures thereof. The front light-emitting active organic EL display device according to claim 7, wherein the thermoplastic polymer has a water transmittance (MVTR) of 40 g at 75% RH (relative humidity) of 100 g · mil / m ² · day or more. 8. The photoluminescent active organic EL according to claim 7, wherein the thermoplastic polymer is selected from the group consisting of polystyrene, polybutadiene, polyisoprene, polyolefin, thermoplastic copolymers including one or more thereof, and mixtures thereof. Display elements. The front-emitting active organic EL display device according to any one of claims 1 to 3, wherein the circular polarizing film has a structure in which a polarizing film and a quarter-wave retardation film are laminated using an adhesive layer.  The circular polarizing film and the transparent dehumidifying film are bonded to each other, and provide dehumidifying function and the function of blocking the light emitted from the outside to be reflected back to the outside, The circular polarizing film has a structure in which a polarizing film and a quarter-wavelength (λ) retardation film are adhered to each other, and the polarization component of the external incident light is allowed to be transmitted, but the polarization component is reflected by the organic EL display element. Does not allow penetration of The transparent dehumidifying film is made of a mixture including a material having water removal properties and a thermoplastic polymer, and the material having water removal properties includes organo metal compounds, metal hydrides, and metals. Dehumidified polarizing film for a top-emitting active organic EL display device, characterized in that at least any one selected from the group consisting of a metal oxide (metal oxide) or a mixture thereof.  16. The dehumidifying polarizing film of claim 15, wherein the organometallic compound is selected from a compound represented by the following [Formula 1] or a mixture thereof. [Formula 1] [Me-R _m R ' _n ] _x In Formula 1, Me is one or two or more of the same or different metals selected from the group consisting of alkali metals, alkaline earth metals, aluminum, titanium, zirconium, and silicon, R is any one selected from the group consisting of a saturated or unsaturated alkyl group, a saturated or unsaturated aryl group, a saturated or unsaturated alkyloxy group, and a saturated or unsaturated allyloxy group, R ′ is any one selected from the group consisting of hydrogen, saturated or unsaturated alkyl groups, saturated or unsaturated aryl groups, saturated or unsaturated alkyloxy groups, and saturated or unsaturated allyloxy groups, m and n are each an integer of 0 ≦ m or n ≦ 4, and the sum thereof m + n is 1 ≦ m + n ≦ 4, x is 1 or an integer greater than 1. The metal hydride of claim 15, wherein the metal hydride is an alkali metal hydride, an alkaline earth metal hydride, an alkali metal hydride including boron or aluminum, an alkaline earth metal hydride including boron or aluminum, and Dehumidifying polarizing film for a top-emitting active organic EL display device, characterized in that any one selected from the group consisting of a mixture thereof.       The dehumidifying polarizing film for a top-emitting active organic EL display device according to claim 15, wherein the metal is selected from the group consisting of a metal having a higher ionization tendency than hydrogen or a mixture thereof.        16. The dehumidifying polarizing film of claim 15, wherein the metal oxide is selected from the group consisting of alkali metal oxides, alkaline earth metal oxides or mixtures thereof. The method of claim 15, wherein the thermoplastic polymer has a moisture permeability (MVTR) at 40 ℃, 75% RH (relative humidity) of more than 1100g · mil / m ² · day dehumidification for the front-emitting active organic EL display device Polarizing film. The photoluminescent active organic EL of claim 15, wherein the thermoplastic polymer is selected from the group consisting of polystyrene, polybutadiene, polyisoprene, polyolefin, thermoplastic copolymers including one or more thereof, and mixtures thereof. Dehumidifying polarizing film for display element.

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