KR20130136805A - Flexible display device - Google Patents

Abstract

The flexible display device of the present invention is to prevent the warpage of the flexible display device in high temperature and humidity by forming a separate barrier layer for preventing the penetration of moisture into the surface of a polarizing device. The flexible display device includes a display panel outputting an image; a polarizing plate bonded to the upper part of the display panel. The polarizing plate comprises a polarizing device, an inorganic layer having a low moisture absorption rate in the upper and the lower part of the polarizing device, and a first and a second barrier layer formed by depositing an organic layer on the inorganic layer.

Description

[0001] FLEXIBLE DISPLAY DEVICE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible display device, and more particularly, to a flexible display device having a polarizing plate that is prevented from moisture permeation.

In recent information society, the importance of display devices as visual information delivery media is getting more emphasized, and in order to take a major position in the future, it is necessary to meet requirements such as low power consumption, thinning, light weight, and high image quality.

The display device may include a cathode ray tube (CRT), an electroluminescence (EL), a light emitting diode (LED), a vacuum fluorescent display (VFD) A liquid crystal display (LCD), such as an organic light emitting display (OLED), a field emission display (FED), and a plasma display panel (PDP) ), Which can not emit light itself.

On the other hand, a flexible display device which is not damaged even if the display device is folded or rolled is expected to become a new technology in the display device field. Currently, various obstacles exist in the implementation of flexible display devices, but thin film transistor liquid crystal display devices and organic light emitting display devices will become mainstream along with technology development.

Hereinafter, the flexible display device will be described in detail with reference to the drawings.

1A and 1B are photographs illustrating a general flexible display device.

The flexible display device is called a desktop display device. As shown in the drawing, the flexible display device is implemented on a thin substrate such as plastic and is not damaged when folded or rolled like paper. It is one of the next generation display devices. A liquid crystal display device and an organic light emitting display device are promising.

The liquid crystal display device is an apparatus for displaying an image using the optical anisotropy of a liquid crystal. Since it has excellent visibility and average power consumption as compared with conventional CRTs, it is smaller than CRTs with the same screen size, And is spotlighted as a display device.

Since the organic light emitting display device itself emits light by itself, visibility is good even when a dark place or external light enters, and since the response speed, which is an important criterion for judging the performance of a mobile display device, is fast among existing display devices, Video can be implemented. In addition, the organic light emitting display device can be slimmed in various mobile devices such as a mobile phone because the OLED display has an ultra-thin design.

In order to realize such a flexible display device, it is necessary to secure the flexibility of the substrate. Currently, plastic or stainless steel (SUS) flexible substrate is used instead of the conventional glass substrate in order to secure the flexibility of the substrate.

At this time, in the liquid crystal display device, polarizing plates of linear polarization orthogonal to each other are attached on and below the liquid crystal panel for liquid crystal driving, and in the organic light emitting display device, A polarizing plate of circular polarization is attached.

In addition, since the flexible display device is made of a large number of films, warpage may occur in a high temperature and high humidity environment to affect a product. Moisture is the main cause of warpage, which is caused by the properties of polyvinyl alcohol (PVA) used in polarizers.

The PVA has a water absorption rate of 30% or more and is vulnerable to moisture, and tri-acetyl cellulose (TAC), which fixes the PVA, also has a water absorption rate 10 times higher than that of a general film. That is, the polarizing plate may not have sufficient heat and moisture resistance of the TAC, and thus, polarization performance such as polarization degree, color, etc. may be degraded in a high temperature and high humidity environment.

In particular, in the case of a general display device in which a polarizing plate is attached to a glass, the glass does not warp because the glass catches the polarization plate even in a high temperature and high humidity environment, but in the case of a flexible display using a flexible substrate, the polarization plate for moisture is There is no fixing means to hold, so it becomes vulnerable to moisture.

An object of the present invention is to provide a flexible display device capable of improving flexure of a flexible display device in a high temperature and high humidity environment.

Other objects and features of the present invention will be described in the configuration and claims of the invention which will be described later.

According to an aspect of the present invention, there is provided a flexible display device including: a display panel for outputting an image; And a polarizing plate attached to an upper portion of the display panel, wherein the polarizing plate is formed of an inorganic film having a low water absorption rate on the polarizer and the polarizer, or an organic film deposited on the inorganic film. Characterized in that consisting of.

Here, the display panel may be one of a liquid crystal display device and an organic light emitting display device.

In this case, the polarizer further includes a protective film attached to the upper surface of the polarizer.

In this case, the polarizer is attached to the upper portion of the display panel using an adhesive.

And a first support formed on the surface of the first barrier film.

At this time, it characterized in that it further comprises a second support formed on the surface of the second barrier film.

At this time, the first and second support is characterized in that consisting of tri-acetyl cellulose (TAC).

In this case, the first and second barrier films include inorganic films having low water absorption rates such as SiNx, TiOx, AlOx, and SiOx, or spin-on-glass (SOG) and benzocyclobutene (BCB) on the inorganic films. ), Acrylic resin, epoxy resin, polyvinyl phenol (Polyvinyl Phenol; PVP) is characterized in that it consists of a hybrid structure of two or more layers on which an organic film is deposited.

In this case, the inorganic film or the organic film is characterized in that made by one time or repeatedly deposited on both sides of the polarizing element.

In addition, another flexible display device of the present invention includes a display panel for outputting an image; And a polarizer attached to an upper portion of the display panel, wherein the polarizer includes a polarizer and an inorganic film having a low water absorption rate on the polarizer, or a barrier film formed by depositing an organic film on the inorganic film.

At this time, it characterized in that it further comprises a first support formed on the surface of the barrier film.

At this time, it characterized in that it further comprises a second support formed on the lower surface of the polarizing element.

In this case, the barrier film is an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, SiOx or the like, or spin-on-glass (SOG), benzocyclobutene (BCB), acrylic resin, It is characterized by consisting of a hybrid structure of at least two layers on which an organic film such as epoxy resin, polyvinyl phenol (Polyvinyl Phenol; PVP) is deposited.

In this case, the inorganic film or the organic film is characterized in that made by one deposition or repeatedly deposited on the upper surface of the polarizing element.

As described above, the flexible display device according to the present invention can prevent the bending of the flexible display device in a high temperature and high humidity state by further forming a barrier layer on the surface of the polarizer to prevent the penetration of moisture. . As a result, the reliability of the flexible display device can be improved.

1A and 1B are photographs showing a typical flexible display device as an example.
2 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a first exemplary embodiment of the present invention.
3 is a cross-sectional view illustrating the display device shown in FIG. 2 as an example.
4 is a flowchart sequentially illustrating a method of manufacturing a flexible display device according to a first embodiment of the present invention.
5A through 5D are cross-sectional views sequentially illustrating a method of manufacturing a flexible display device according to a first embodiment of the present invention.
6 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a second exemplary embodiment of the present invention.
7 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a third exemplary embodiment of the present invention.
8 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a fourth exemplary embodiment of the present invention.
9 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a fifth exemplary embodiment of the present invention.
10 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a sixth exemplary embodiment of the present invention.

Hereinafter, preferred embodiments of the flexible display device according to the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

2 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a first exemplary embodiment of the present invention.

3 is a cross-sectional view illustrating the display device illustrated in FIG. 2 by way of example, and illustrates an organic light emitting display device as a display device.

Referring to FIG. 2, the flexible display device according to the first embodiment of the present invention includes a display panel 110 for outputting an image, and a polarizer 120 is disposed on the display panel 110, ).

Here, the upper and lower portions of the display panel 110 are not limited to specific positions, and thus the polarizer 120 may be attached to the lower portion of the display panel 110 using the adhesive 130.

A protective film 140 of hard coating may be further adhered to the upper surface of the polarizer 120.

At this time, the display panel 110 may be one of a liquid crystal display device and an organic light emitting display device.

3, an anode 112 made of transparent oxide is formed on a substrate 111 made of plastic or stainless steel, and an anode 112 made of a transparent oxide is formed on a substrate 111 made of plastic or stainless steel. A hole transport layer 113, an emission layer 114, an electron transport layer 115, an electron injection layer 116, and a cathode (117) are stacked.

Based on the above structure, the organic electroluminescence device has a structure in which the holes injected from the anode 112 and the electrons injected from the cathode 117 are coupled to each other in the light emitting layer 114 via the transport layers 113 and 115 for transport, The light of the wavelength corresponding to the energy difference in the light emitting layer 114 is generated while moving to the energy level.

At this time, the light emitting layer 114 may more specifically include a red light emitting layer 114a, a green light emitting layer 114b, and a blue light emitting layer 114c for light emission of white light.

The polarizing plate 120 is attached to the upper portion of the display panel 110 using the adhesive 130 and the polarizing plate 120 is made of a circularly polarized polarizing plate to prevent reflection of external light.

On the other hand, when the display panel 110 is formed of a liquid crystal display device, an upper polarizer 120 having a light absorption axis in the horizontal direction is disposed on the display panel 110, for example. Although not shown in the figure, a backlight unit is disposed below the display panel 110, and a lower polarizer plate is disposed between the display panel 110 and the backlight unit.

In the case where the display panel 110 is constituted by a liquid crystal display device, the display panel 110 may be composed of two substrates and a liquid crystal layer formed therebetween.

At this time, a thin film transistor array is formed on the lower substrate. The thin film transistor array includes a plurality of data lines to which R, G, and B data voltages are supplied, a plurality of gate lines to which gate pulses are supplied to cross the data lines, A plurality of pixel electrodes for charging a data voltage to the liquid crystal cells, and a storage capacitor connected to the pixel electrode to maintain the voltage of the liquid crystal cell. A color filter array is formed on the upper substrate, and the color filter array includes a black matrix, a color filter, and the like.

In the flexible display device according to the first exemplary embodiment of the present invention configured as described above, the polarizing plate 120 includes a first support 123a and a second support 123b and the first support 123a and a second support 123b. It includes a polarizing element 121 positioned between.

The first support 123a and the second support 123b may be formed of a general protection film without phase retardation, for example, made of tri-acetyl cellulose (TAC). Can be.

The polarizing element 121 refers to a film that can be converted into natural polarized light or polarized light. The polarizing element 121 has a function of passing one polarized light component when the incident light is divided into two polarized light components orthogonal to each other, and has a function of absorbing, reflecting, and scattering the other polarized light component May be used.

The optical film used for the polarizing element 121 is not particularly limited. For example, the optical film may be a film obtained by stretching a polymer film containing a polyvinyl alcohol (PVA) based resin containing iodine or a dichroic dye as a main component Film, an O-type polarizing element in which a liquid crystal composition containing a dichroic substance and a liquid crystal compound are aligned in a certain direction, and an E-type polarizing element in which a lyotropic liquid crystal is oriented in a certain direction.

In the polarizer 120 according to the first embodiment of the present invention, a first barrier layer 122a is formed between the first support 123a and the polarizer 121, and the second support ( A second barrier film 122b is formed between the 123b and the polarizer 121.

The first barrier layer 122a and the second barrier layer 122b may prevent moisture from penetrating into the polarizing element 121 which is vulnerable to moisture, thereby improving the bending phenomenon of the flexible display device and improving reliability. That is, the polarizer 121 and the first and second supports 123a and 123b have a water absorption of about 100 times and 10 times higher than that of the general film, but conventionally, the polarizer 121 and the first and second 2 There was no means for blocking the water penetrating into the support (123a, 123b). However, in the first embodiment of the present invention, the first and second barrier films 122a and 122b are formed on and under the polarizer 121 to prevent moisture from penetrating into the polarizer 121. As a result, the bending of the polarizing plate can be prevented even in a high temperature and high humidity environment.

The first and second barrier films 122a and 122b may be formed of an inorganic film having low water absorption, such as SiNx, TiOx, AlOx, or SiOx, or spin-on-glass (SOG) or benzocyclo on the inorganic film. Butene (benzocyclobutene; BCB), acrylic resin, epoxy resin, polyvinyl phenol (Polyvinyl Phenol (PVP)) may be composed of a hybrid (hybrid) structure of two or more layers on which an organic film is deposited.

The inorganic layer or the organic layer may be formed by depositing or repeatedly depositing both surfaces of the polarizer 121.

Hereinafter, a method of manufacturing an organic light emitting display device according to a first embodiment of the present invention configured as described above will be described in detail with reference to the accompanying drawings.

4 is a flowchart sequentially illustrating a method of manufacturing a flexible display device according to a first embodiment of the present invention.

5A to 5D are cross-sectional views sequentially illustrating a method of manufacturing a flexible display device according to a first embodiment of the present invention.

As shown in FIG. 5A, a predetermined film is stretched to provide a polarizer 121 (S110).

For example, the polarizing element 121 may be one in which a dichroic substance is adsorbed and oriented on a PVA-based film.

The PVA resin constituting the polarizing element 121 can be obtained by saponifying a polyvinyl acetate resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith.

The polarizing element 121 can be manufactured through a process of dyeing the PVA film as described above with a dichroic material, crosslinking with a boric acid aqueous solution, uniaxial stretching, washing with water and drying.

Thereafter, as illustrated in FIG. 5B, first and second barrier films 122a and 122b are deposited on the lower surface of the polarizer 121 (S120).

At this time, the first and second barrier films 122a and 122b prevent moisture from penetrating into the polarizing element 121 which is vulnerable to moisture, thereby improving warpage of the flexible display device and improving reliability .

To this end, the first and second barrier films 122a and 122b may be formed of an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, or SiOx, or SOG, BCB, acrylic resin, epoxy resin, PVP, or the like on the inorganic film. It may be composed of a hybrid structure of two or more layers in which an organic film is deposited. In this case, the inorganic film or the organic film may be formed by depositing or repeatedly depositing both surfaces of the polarizer 121.

Thereafter, as illustrated in FIG. 5C, the polarizer 120 is formed by forming first and second supports 123a and 123b on the surfaces of the first and second barrier layers 122a and 122b, respectively (S130). ).

The first and second supports 123a and 123b are films for protecting the mechanically weak polarizer 121, and may be a film having excellent transparency, mechanical strength, thermal stability, isotropy, and the like. The first and second supports 123a and 123b may be made of a general protective film without phase delay, and may be made of, for example, TAC.

Subsequently, as shown in FIG. 5D, the protective film 140 of the hard coating may be additionally attached to the upper surface of the polarizing plate 120 on which the first and second supports 123a and 123b are formed (S140). ).

In addition, the polarizer 120 is attached to the display panel 110 using the adhesive 130 (S150).

The pressure-sensitive adhesive 130 is not particularly limited as long as it can sufficiently adhere the display panel 110 and the polarizer 120 and is excellent in optical transparency and does not change with time. For example, PVA resin And an adhesive composition containing a crosslinking agent.

At this time, the display panel 110 may be one of a liquid crystal display device and an organic light emitting display device.

As described above, when the display panel 110 is formed of an organic light emitting display, a cathode made of transparent oxide is formed on a substrate made of plastic or stainless steel, and a hole transporting layer, a light emitting layer, , An electron injection layer, and a cathode may be stacked.

When a polyimide (PI) material is used as the substrate, a plastic film of polyethylene terephthalate (PET) or a back film made of metal of stainless steel may be attached to the back surface of the substrate .

Meanwhile, in the flexible display device of the present invention, as the barrier film is formed as a protective film on the polarizer, the support may not be formed thereon, which will be described in detail with reference to the second embodiment of the present invention.

6 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a second exemplary embodiment of the present invention.

In this case, the flexible display device according to the second embodiment of the present invention is substantially the same as the first embodiment of the present invention except that a support is not formed on the polarizer.

As shown in the figure, the flexible display device according to the second embodiment of the present invention includes a display panel 210 for outputting an image, and a polarizer 220 is attached to the upper part of the display panel 210 with an adhesive 230 ).

A protective film 240 of hard coating may be further attached to the upper surface of the polarizer 220.

At this time, as described above, the display panel 210 may be one of a liquid crystal display device and an organic light emitting display device.

Although not shown, when the display panel 210 is formed of an organic light emitting display, a positive electrode made of transparent oxide is formed on a substrate made of plastic or stainless steel, and a hole transport layer, a light emitting layer, , An electron injection layer and a cathode are stacked.

A polarizing plate 220 is attached to the upper portion of the display panel 210 using the adhesive 230 and the polarizing plate 220 is a circularly polarized polarizing plate to prevent reflection of external light.

On the other hand, when the display panel 210 is constituted by a liquid crystal display device, an upper polarizer 220 having a light absorption axis in the horizontal direction is disposed on the display panel 210, for example. Although not shown, a backlight unit is disposed below the display panel 210, and a lower polarizer plate is disposed between the display panel 210 and the backlight unit.

When the display panel 210 is formed of a liquid crystal display device, the display panel 210 may include two substrates and a liquid crystal layer formed therebetween.

In the flexible display device according to the second exemplary embodiment of the present invention configured as described above, the polarizing plate 220 includes a first barrier layer 222a and a second barrier layer 222b, and the first barrier layer 222a and the second layer. A polarizer 221 is disposed between the barrier layer 222b and a support 223 formed under the second barrier layer 222b.

As described above, the support 223 may be made of a general protective film without phase delay, for example, may be made of TAC.

The optical film used for the polarizing element 221 is not particularly limited. For example, a stretched film of a polymer film containing a PVA-based resin containing iodine or a dichromatic dye as a main component, An O-type polarizing element in which a liquid crystal composition containing a compound is oriented in a certain direction, and an E-type polarizing element in which a lyotropic liquid crystal is oriented in a certain direction.

The first and second barrier layers 222a and 222b prevent moisture from penetrating into the polarizer 221 which is vulnerable to moisture, thereby improving the bending phenomenon of the flexible display device and improving reliability.

The first and second barrier films 222a and 222b may be formed of an inorganic film having low water absorption such as SiNx, TiOx, AlOx, or SiOx, or an organic film such as SOG, BCB, acrylic resin, epoxy resin, PVP, or the like on the inorganic film. It may be composed of a hybrid structure of two or more layers in which a film is deposited.

The inorganic layer or the organic layer may be formed by depositing or repeatedly depositing both surfaces of the polarizer 221.

As described above, the second embodiment of the present invention shows an example in which the support is not formed on the polarizer, but the present invention is not limited thereto. According to the present invention, as the barrier film is formed as a protective film on the lower portion of the polarizer, the support may not be formed on the lower portion thereof, which will be described in detail through the third embodiment of the present invention.

7 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a third exemplary embodiment of the present invention.

In this case, the flexible display device according to the third embodiment of the present invention is substantially the same as the first embodiment of the present invention except that a support is not formed under the polarizer.

As shown in the drawing, the flexible display device according to the third embodiment of the present invention includes a display panel 310 for outputting an image, and a polarizer 320 is disposed on the display panel 310, ).

A protective film 340 of hard coating may be further attached to the upper surface of the polarizing plate 320.

In this case, as described above, the display panel 310 may be formed of one of a liquid crystal display device and an organic light emitting display device. When the display panel 310 is formed of an organic light emitting display device, the display panel 310 may be used. The polarizing plate 320 is attached to the upper portion of the adhesive using the adhesive 330, the polarizing plate 320 is made of a circular polarizing polarizing plate to prevent external light reflection.

In the flexible display device according to the third embodiment of the present invention configured as described above, the polarizing plate 320 may include a first barrier layer 322a and a second barrier layer 322b, and the first barrier layer 322a and the second barrier layer. The polarizer includes a polarizer 321 positioned between the barrier layer 322b and a support 323 formed on the first barrier layer 322b.

As described above, the support 323 may be made of a general protective film without phase delay, for example, may be made of TAC.

The optical film used for the polarizing element 321 is not particularly limited. For example, a stretched film of a polymer film containing a PVA-based resin containing iodine or a dichromatic dye as a main component, An O-type polarizing element in which a liquid crystal composition containing a compound is oriented in a certain direction, and an E-type polarizing element in which a lyotropic liquid crystal is oriented in a certain direction.

The first and second barrier layers 322a and 322b prevent moisture from penetrating into the polarizer 321 which is vulnerable to moisture, thereby improving the bending phenomenon of the flexible display device and improving reliability.

The first and second barrier films 322a and 322b may be formed of an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, or SiOx, or an organic material such as SOG, BCB, acrylic resin, epoxy resin, PVP, or the like on the inorganic film. It may be composed of a hybrid structure of two or more layers in which a film is deposited.

The inorganic film or the organic film may be formed by depositing or repeatedly depositing both surfaces of the polarizer 321.

As described above, the first and second embodiments of the present invention show an example in which a support is not formed on each of the upper and lower portions of the polarizer, but the present invention is not limited thereto. According to the present invention, as the barrier film is formed as a protective film on the upper and lower portions of the polarizer, the support may not be formed on both the upper and lower portions thereof, which will be described in detail through the following fourth embodiment of the present invention.

8 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a fourth exemplary embodiment of the present invention.

In this case, the flexible display device according to the fourth exemplary embodiment of the present invention is substantially the same as that of the first exemplary embodiment of the present invention except that the support is not formed on both the upper and lower portions of the polarizer. .

As shown in the figure, the flexible display device according to the fourth embodiment of the present invention includes a display panel 410 for outputting an image, and the polarizer 420 is formed on the display panel 410 on the adhesive 430. ) Is attached.

The protective film 440 of the hard coating may be additionally attached to the upper surface of the polarizing plate 420.

In this case, as described above, the display panel 410 may be formed of one of a liquid crystal display device and an organic light emitting display device. When the display panel 410 is formed of an organic light emitting display device, the display panel 410 may be used. The polarizing plate 420 is attached to the upper portion of the adhesive using the adhesive 430, the polarizing plate 420 is made of a circular polarizing polarizing plate to prevent external light reflection.

In the flexible display according to the fourth exemplary embodiment of the present invention configured as described above, the polarizing plate 420 may include the first barrier layer 422a and the second barrier layer 422b, and the first barrier layer 422a and the second barrier layer. And a polarizer 421 positioned between the barrier films 422b.

As described above, the optical film used for the polarizing element 421 is not particularly limited, but for example, a stretched film or a dichroic substance of a polymer film mainly composed of PVA-based resin containing iodine or a dichroic dye. And an O-type polarizing element in which a liquid crystal composition containing a liquid crystal compound is oriented in a fixed direction, and an E-type polarizing element in which a lyotropic liquid crystal is oriented in a fixed direction.

The first and second barrier layers 422a and 422b prevent moisture from penetrating into the polarizer 421, which is vulnerable to moisture, thereby improving the warpage of the flexible display device and improving reliability.

The first and second barrier films 422a and 422b may be formed of an inorganic film having low water absorption such as SiNx, TiOx, AlOx, or SiOx, or an organic material such as SOG, BCB, acrylic resin, epoxy resin, PVP, or the like on the inorganic film. It may be composed of a hybrid structure of two or more layers in which a film is deposited.

The inorganic layer or the organic layer may be formed by depositing or repeatedly depositing both surfaces of the polarizer 421.

On the other hand, the bending of the polarizer in a high temperature and high humidity environment is mainly due to the moisture introduced from the outside may not form a barrier film on the lower portion of the polarizer, which will be described in detail through the fifth embodiment of the present invention .

9 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a fifth exemplary embodiment of the present invention.

In this case, the flexible display device according to the fifth exemplary embodiment of the present invention is substantially the same as the first exemplary embodiment of the present invention except that a barrier layer is not formed under the polarizer.

As shown in the figure, the flexible display device according to the fifth embodiment of the present invention includes a display panel 510 for outputting an image, and a polarizer 520 is formed on the upper portion of the display panel 510. ) Is attached.

In addition, a hard coat protective film 540 may be additionally attached to the upper surface of the polarizing plate 520.

In this case, as described above, the display panel 510 may be configured as one of a liquid crystal display device and an organic light emitting display device. When the display panel 510 is configured as an organic light emitting display device, the display panel 510 may be used. The polarizing plate 520 is attached to the upper portion of the adhesive using the adhesive 530, the polarizing plate 520 is made of a circular polarizing polarizing plate to prevent external light reflection.

In the flexible display device according to the fifth exemplary embodiment of the present invention configured as described above, the polarizer 520 may include a first support 523a and a second support 523b, and the first support 523a and a second support 523b. And a polarization element 521 positioned between them.

As described above, the first and second supports 523a and 523b may be made of a general protective film without phase delay, and may be made of, for example, TAC.

The optical film used for the polarizing element 521 is not particularly limited, but for example, a stretched film, a dichroic substance and a liquid crystal of a polymer film mainly composed of PVA-based resin containing iodine or a dichroic dye. O type polarizing element which orientated the liquid crystalline composition containing a compound to a fixed direction, E type polarizing element which orientated a lyotropic liquid crystal to a fixed direction, etc. are mentioned.

The polarizing plate 520 according to the fifth exemplary embodiment of the present invention is characterized in that a barrier film 522 is formed between the first support 523a and the polarizing element 521.

The barrier layer 522 prevents moisture from penetrating into the polarizer 521, which is vulnerable to moisture, thereby improving the bending phenomenon of the flexible display device, thereby improving reliability.

The barrier layer 522 has a hybrid structure of at least two layers in which an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, SiOx, or the like, and an organic film such as SOG, BCB, acrylic resin, epoxy resin, or PVP is deposited on the inorganic film. It can be configured as.

The inorganic layer or the organic layer may be formed by one deposition or repeatedly deposited on the upper surface of the polarizer 521.

Meanwhile, as described above, the flexible display device of the present invention may not form a support thereon as the barrier film is formed as a protective film on the polarizer, and this will be described in detail through the following sixth embodiment of the present invention. Explain.

10 is a cross-sectional view schematically illustrating a structure of a flexible display device according to a sixth embodiment of the present invention.

In this case, the flexible display device according to the sixth exemplary embodiment of the present invention is substantially the same as the fifth exemplary embodiment of the present invention except that a barrier layer is not formed on the polarizer.

As shown in the drawing, the flexible display device according to the sixth embodiment of the present invention includes a display panel 610 for outputting an image, and a polarizer 620 is formed on the upper portion of the display panel 610. ) Is attached.

In addition, the protective film 640 of the hard coating may be additionally attached to the upper surface of the polarizing plate 620.

In this case, as described above, the display panel 610 may be formed of one of a liquid crystal display device and an organic light emitting display device. When the display panel 610 is formed of an organic light emitting display device, the display panel 610 The polarizing plate 620 is attached to the upper portion of the adhesive using the adhesive 630, the polarizing plate 620 is made of a circular polarizing polarizing plate to prevent external light reflection.

In the flexible display according to the sixth exemplary embodiment of the present invention, the polarizing plate 620 includes a polarizer 621, a barrier layer 622 formed on the polarizer 621, and the polarizer 621. It includes a support 623 formed at the bottom.

As described above, the support 623 may be made of a general protective film without phase delay, for example, may be made of TAC.

The optical film used for the polarizing element 621 is not particularly limited, but for example, a stretched film, a dichroic substance and a liquid crystal of a polymer film mainly composed of PVA-based resin containing iodine or a dichroic dye. O type polarizing element which orientated the liquid crystalline composition containing a compound to a fixed direction, E type polarizing element which orientated a lyotropic liquid crystal to a fixed direction, etc. are mentioned.

The barrier layer 622 serves to improve the reliability by preventing the penetration of moisture into the polarizer 621 which is vulnerable to moisture, thereby improving the warpage of the flexible display device.

The barrier layer 622 has a hybrid structure of two or more layers in which an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, SiOx or the like, or an organic film such as SOG, BCB, acrylic resin, epoxy resin, PVP, or the like is deposited on the inorganic film. It can be configured as.

The inorganic layer or the organic layer may be formed by one deposition or repeatedly deposited on the upper surface of the polarizer 621.

While a great many are described in the foregoing description, it should be construed as an example of preferred embodiments rather than limiting the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

110,210,310,410,510,610: display panel
120,220,320,420,520,620: Polarizer
121,221,321,421,521,621: polarizer
122a, 222a, 322a, 422a, 122b, 222b, 322b, 422b, 522, 622: barrier film
123a, 523a, 123b, 523b, 223,323,623
130,230,330,430,530,630: Adhesive
140,240,340,440,540,640: Protective film

Claims (14)

A display panel for outputting an image; And
And a polarizer attached to an upper portion of the display panel,
The polarizing plate may include a polarizing element and an inorganic layer having a low water absorption rate on the upper and lower portions of the polarizing element, or first and second barrier layers formed by depositing an organic layer on the inorganic layer. The flexible display device according to claim 1, wherein the display panel is one of a liquid crystal display device and an organic light emitting display device. The flexible display device according to claim 2, further comprising a protective film attached to an upper surface of the polarizer. The flexible display device according to claim 3, wherein the polarizer is attached to an upper portion of the display panel using an adhesive. The flexible display device of claim 1, further comprising a first support formed on a surface of the first barrier layer. The flexible display device of claim 5, further comprising a second support formed on a surface of the second barrier layer. The flexible display device of claim 6, wherein the first and second supports are made of tri-acetyl cellulose (TAC). 8. The method of claim 7, wherein the first and second barrier films are inorganic films having low water absorption, such as SiNx, TiOx, AlOx, SiOx, or spin-on-glass (SOG) or benzocyclobutene on the inorganic films. A flexible display device comprising a hybrid structure of at least two layers in which organic films such as (benzocyclobutene; BCB), acrylic resin, epoxy resin, and polyvinyl phenol (PVP) are deposited. The flexible display device of claim 8, wherein the inorganic layer or the organic layer is formed by repeatedly depositing or repeatedly depositing both surfaces of the polarizer. A display panel for outputting an image; And
And a polarizer attached to an upper portion of the display panel,
The polarizing plate may include a polarizer and an inorganic film having a low water absorption rate on the polarizer, or a barrier film formed by depositing an organic film on the inorganic film. The flexible display device of claim 10, further comprising a first support formed on a surface of the barrier layer. The flexible display device of claim 11, further comprising a second support formed on a lower surface of the polarizer. The method of claim 12, wherein the barrier film is an inorganic film having a low water absorption rate such as SiNx, TiOx, AlOx, SiOx or the like, or spin-on-glass (SOG) or benzocyclobutene (BCB) on the inorganic film. And a hybrid structure of at least two layers on which an organic film, such as acrylic resin, epoxy resin, and polyvinyl phenol (PVP), is deposited. The flexible display device of claim 13, wherein the inorganic layer or the organic layer is formed by depositing or repeatedly depositing an upper surface of the polarizer.

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