KR20200091838A - Flexible display device and method for manufacturing the same - Google Patents

Abstract

Provided are a flexible display device and a manufacturing method thereof. A flexible substrate including a display part on which an image is displayed and a non-display part extending and bent from one side of the display part is formed. A plurality of support substrates spaced apart from each other while placed on the flexible substrate is formed to easily bend the flexible substrate. A control layer for controlling the bending radius of the flexible substrate is placed between the plurality of support substrates. A stress absorbing layer for absorbing the stress of the control layer while being placed in one surface of the control layer is included. The stress absorbing layer can minimize the occurrence of wrinkles in a flexible substrate area placed in a position corresponding to the control layer.

Description

Flexible display device and manufacturing method of flexible display device {FLEXIBLE DISPLAY DEVICE AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a flexible display device and a method of manufacturing the flexible display device, and more particularly, to a flexible display device and a method of manufacturing a flexible display device having improved stress under a flexible substrate.

In recent years, a flexible display device capable of displaying an image even if it is curved like paper by forming a display unit, a wiring, or the like on a flexible substrate such as plastic, which is a flexible material, has attracted attention as a next-generation display device.

As the range of application of a flexible display device to a personal computer and a monitor as well as a computer monitor and TV varies, research into a flexible display device having a large display area and a reduced volume and weight has been conducted. In particular, the organic light emitting display device (Organic Light Emitting Display; OLED), unlike a liquid crystal display (Liquid Crystal Display; LCD) does not require a separate light source, since it can be implemented in a relatively thin thickness, the organic light emitting display device Efforts are being made to manufacture a flexible display device.

[Related technical documents]

1.Narrow bezel type array substrate and liquid crystal display device having the same (Patent Application No. 10-2010-0115912)

2. Display device and its manufacturing method (Patent application No. 10-2009-0124052)

As the display device is miniaturized, efforts to reduce the bezel area in order to increase the effective display screen size in the display device having the same area are continuing. Accordingly, a technique for realizing an optimal bezel region has been introduced by using a flexible substrate as a substrate of a display device and bending a non-display area, which is an area that does not display an image on the flexible substrate. The flexible substrate has a thickness of about several μm for easy bending, and is made of a material having excellent flexibility.

On the other hand, generally, a support film for supporting the flexible substrate is disposed under the flexible substrate, and various members are disposed to optimally bend the flexible substrate. However, when the flexible substrate of a thin thickness is bent, stress is applied to the supporting film and/or the flexible substrate at positions corresponding to the various members due to stress generated on the supporting film and various members as described above, so that the flexible substrate is There is a problem that is deformed. Accordingly, a problem that reliability of the flexible display device deteriorates is caused.

In addition, as the display device becomes thinner, efforts to reduce the thickness of the display device continue. Accordingly, a technique of integrating various system parts and circuit parts included in the display device on the back surface of the display substrate of the display device is required. When a flexible substrate having a thin thickness is used as a display substrate, there is a problem in that stress occurs in the flexible substrate at a position corresponding to the stress generated by the system portion and the circuit portion, resulting in deformation of the flexible substrate.

The inventors of the present invention have invented a new structure and a manufacturing method of a flexible display device that minimizes deformation of the flexible substrate by reducing stress applied to the flexible substrate at a specific location when the flexible substrate is bent.

Accordingly, a problem to be solved by the present invention is to provide a flexible display device and a method for manufacturing the flexible display device that minimize deformation of the flexible substrate.

Another problem to be solved by the present invention is a flexible display device that minimizes deformation of a flexible substrate at a position corresponding to the system portion and the circuit portion when the system portion and the circuit portion are disposed on the rear surface of the flexible substrate so that the display device has an optimal thickness. And a method for manufacturing a flexible display device.

The solving problems according to an embodiment of the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Provided is a flexible display device and a method of manufacturing the same, which minimize deformation of the flexible substrate according to an embodiment of the present invention.

A flexible substrate including a display portion on which an image is displayed and a non-display portion extending from one side of the display portion is formed. Positioned on the flexible substrate, a plurality of support substrates spaced apart from each other is formed to facilitate bending of the flexible substrate. A control layer that controls the bending radius of the flexible substrate is positioned between the plurality of support substrates. It is located on one side of the control layer and includes a stress absorbing layer that absorbs the stress of the control layer. The stress-absorbing layer can minimize the occurrence of wrinkles in the flexible substrate area at a position corresponding to the control layer.

According to another feature of the invention, the stress absorbing layer is characterized in that it comprises an adhesive layer and a cushion layer.

According to another feature of the invention, the cushion layer is characterized in that the polyolefin (Polylolenfin) film.

According to another feature of the invention, the control layer is made of any one of stainless steel (SUS), polyethylene terephthalate (PET) and polycarbonate (PC).

According to another feature of the invention, the control layer is characterized in that the hook (Hook) shape.

According to another feature of the present invention, a part of the control layer has a circular or elliptical shape, and one side of a part of the control layer supports a bent non-display unit.

According to another feature of the present invention, the control layer includes a base portion contacting the stress absorbing layer, a head portion contacting the bent non-display portion, and a connection portion connecting the base portion and the head portion, and the connection portion connecting the top end of the head portion and the base portion The outer surface of the is characterized in that the curved surface or inclined surface.

According to another feature of the present invention, the display unit further comprises an organic light emitting device.

When the system unit and the circuit unit are disposed on the rear surface of the flexible substrate so that the display device according to an exemplary embodiment has an optimal thickness, a flexible display device and a method for manufacturing the flexible display device that minimize deformation of the flexible substrate at a position corresponding thereto Is provided.

A flexible substrate including a non-display unit having a bezel area and bent in a direction of a display unit on which an image is displayed and a rear surface of the display unit is formed. A support substrate supporting the flexible substrate is positioned on the flexible substrate, and a bezel region control layer is formed on one side of the support substrate and controlling a bezel region of the non-display portion. A first stress distribution layer is formed to fix the bezel region control layer and the support substrate, and the first stress dispersion layer can minimize stress generated in a portion of the flexible substrate.

According to another feature of the present invention, the bezel area control layer includes a hook-shaped portion, and the hook-shaped portion is located adjacent to the bezel region.

According to another feature of the present invention, the flexible display device further comprises a system unit that generates a driving voltage and a driving signal for driving the display unit of the flexible substrate.

According to another feature of the present invention, the system unit is located on one surface of the supporting substrate and is formed at a position corresponding to the display unit of the flexible substrate.

According to another feature of the invention, a part of the system portion is characterized by being patterned in a groove shape.

According to another feature of the present invention, the flexible display device further comprises a second stress distribution layer for dispersing stress in the system unit.

According to another feature of the invention, the second stress distribution layer is characterized in that to minimize the stress in the flexible substrate region corresponding to the system unit.

According to another feature of the present invention, the flexible display device further comprises an insulating film connected to one end of the non-display portion of the flexible substrate, a driving element positioned on the insulating film, and a circuit board connected to the insulating film.

According to another feature of the invention, the driving element is characterized in that it is located in correspondence with the groove shape of the system unit.

According to another feature of the present invention, the flexible display device is located on the rear surface of the support substrate and further includes a driving element cover layer formed in a groove region of the system unit to protect the driving element.

According to another feature of the present invention, the flexible display device is positioned between the circuit board and the system unit, and further includes a step compensation layer for compensating for a difference in thickness between the bezel region control layer and the system unit.

A method of manufacturing a flexible display device according to an embodiment of the present invention is provided. A plurality of support substrates spaced apart from each other is formed on a flexible substrate including a display unit and a non-display unit, and a stress absorbing layer is formed on a portion of the support substrates. Then, a control layer for controlling the bending radius of the flexible substrate is disposed on the stress absorbing layer. Finally, the flexible substrate is bent so that the non-display portions correspond to each other.

According to another feature of the invention, the step of forming the stress absorbing layer is characterized in that it comprises the step of forming a bonding layer, a cushion layer, and a bonding layer on any one of the support substrate.

According to another feature of the present invention, a method of manufacturing a flexible organic light emitting display device further comprises forming an organic light emitting element on the display unit.

Specific details of other embodiments are included in the detailed description and drawings.

1 is a schematic perspective view of a flexible organic light emitting diode display including a stress absorbing layer according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view illustrating the stress absorbing layer illustrated in FIG. 1.
3A and 3B are schematic cross-sectional views for describing a shape of a control layer of an organic light emitting diode display according to various embodiments of the present invention.
4 is a schematic cross-sectional view of a flexible organic light emitting diode display according to an exemplary embodiment of the present invention.
5 is a flowchart illustrating a method of manufacturing a flexible organic light emitting display device according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete, and the general knowledge in the technical field to which the present invention pertains. It is provided to fully inform the holder of the scope of the invention, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for describing the embodiments of the present invention are exemplary and the present invention is not limited to the illustrated matters. The same reference numerals refer to the same components throughout the specification. In addition, in the description of the present invention, when it is determined that detailed descriptions of related known technologies may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted. When'include','have','consist of', etc. mentioned in this specification are used, other parts may be added unless'~man' is used. When a component is expressed as a singular number, the plural number is included unless otherwise specified.

In interpreting the components, it is interpreted as including the error range even if there is no explicit description.

In the case of the description of the positional relationship, for example, when the positional relationship of two parts is described as'~top','~upper','~bottom','~side', etc.,'right' Alternatively, one or more other parts may be located between the two parts unless'direct' is used.

An element or layer being referred to as being "on" another element or layer includes all instances of other layers or other elements immediately above or in between.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

The same reference numerals refer to the same components throughout the specification.

The size and thickness of each component shown in the drawings are illustrated for convenience of description, and the present invention is not necessarily limited to the size and thickness of the illustrated component.

In this specification, the flexible display device refers to a display device to which flexibility is given, and is a bendable display device, a rollable display device, an unbreakable display device, and a collapsible display device ( It is used in the same sense as a foldable display device, a twistable display device, a stretchable display device, and a linkable display device.

Each of the features of the various embodiments of the present invention may be partially or wholly combined or combined with each other, technically various interlocking and driving may be possible, and each of the embodiments may be independently implemented with respect to each other or may be implemented together in an associative relationship. It might be.

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

1 is a schematic perspective view of a flexible organic light emitting diode display including a stress absorbing layer according to an embodiment of the present invention. 2 is a schematic perspective view for explaining the stress absorbing layer shown in FIG. 1A.

1 and 2, the flexible organic light emitting diode display 100 includes a flexible substrate 110, an organic light emitting device 120, a plurality of support substrates 130a and 130b, a control layer 140, and an adhesive layer 160 ) And the stress absorbing layer 150.

The flexible substrate 110 is a substrate for supporting various elements of the flexible organic light emitting diode display 100 and is formed of a material having flexibility to allow bending.

The flexible substrate 110 includes a display unit DP and a non-display unit NP extending from one side of the display unit DP. The non-display unit NP includes a bending area BA. The non-display portion NP of the flexible substrate 110A faces at least a portion of the display portion DP.

On the other hand, in this specification, the bending direction is a direction formed by a surface in which the bending area BA is formed from the boundary between the display portion DP and the bending area BA of the flexible substrate 100 on the XY plane to the non-display area NP. Means In other words, referring to FIG. 1, as the flexible substrate 100A is bent, the bending direction, which is a positive direction of the X-axis initially, gradually bends in the X-axis negative direction through the Z-axis negative direction. In this specification, for convenience of description, the bending direction will be described on the assumption that the bending direction is gradually bent from the positive direction of the X axis to the negative direction of the X axis through the negative Z axis.

The flexible substrate 110 may be divided into a display unit DP displaying an image and a non-display unit NP not displaying an image. As shown in FIG. 1, the display unit DP of the flexible substrate 110 is a portion in which the organic light emitting device 120 is positioned on the flexible substrate 110 to display an image, and the non-display unit of the flexible substrate 110 ( NP) is a portion other than the display unit DP. Without being limited thereto, the non-display unit NP may also be a display area depending on the position of the organic light emitting device 120A formed on the flexible substrate 110.

The organic light emitting device 120 is disposed on the display unit DP of the flexible substrate 110. Although not illustrated in FIG. 1, the display unit DP may include a thin film transistor for driving an organic light emitting device. The organic light emitting device 120 includes an anode, an organic light emitting layer, and a cathode, and emits light emitted from the organic light emitting layer to the outside of the display unit DP.

The flexible substrate 110 is generally 10 µm to 30 µm thick. Therefore, because the flexible substrate 110 is thin, it is difficult to keep the shape of the flexible substrate 110 constant without using a separate support means. Accordingly, a plurality of support substrates 130a and 130b are disposed on the rear surface of the flexible substrate 110 to support the flexible substrate 110. The plurality of support substrates 130a and 130b generally have a thickness of 100 μm to 150 μm. In addition, the plurality of support substrates 130a and 130b reduces penetration of moisture or impurities through the flexible substrate 110 from outside the flexible organic light emitting diode display 100. The plurality of support substrates 130a and 130b may be formed of an insulating film or polyethylene terephthalate (PET), but is not limited thereto. In this specification, the top and back surfaces of a specific element are determined based on the state shown in the drawings. That is, the upper surface of a specific element means a surface facing upward in the drawing, and the rear surface of a specific element means a surface facing downward in the drawing.

When a single support substrate is positioned on the rear surface of the display portion DP and the non-display portion NP of the flexible substrate 110, it is difficult to bend the flexible substrate 100 due to the thick thickness of the support substrate itself. Referring to FIG. 1, in the flexible display device 100 according to an exemplary embodiment of the present invention, one of the plurality of support substrates 130a and 130b (130a) is disposed in contact with a part of the display unit DP and the other ( 130b) is disposed in contact with a portion of the non-display portion NP. Therefore, the plurality of support substrates 130a and 130b may be spaced apart from each other to facilitate bending of the flexible substrate 110.

A plurality of support substrates 130a and 130b are not disposed in the bending area BA of the flexible substrate 110. In the flexible organic light emitting diode display 100 according to an exemplary embodiment of the present invention, the supporting substrate is not disposed in the bending area BA, and the plurality of supporting substrates 130a and 130b are among the display unit DP and the non-display unit NP. Since it is disposed only in a portion excluding the bending area BA, a flexible substrate (with a smaller force than the flexible substrate 110 and the supporting substrate is bent together with the supporting substrate disposed on the entire rear surface of the flexible substrate 110) The bending area BA of 110 may be easily bent, and stress applied to the bending area BA of the flexible substrate 110 is reduced.

The control layer 140 is disposed between the plurality of support substrates 130a and 130b to fill at least a portion of the space between the plurality of support substrates 130a and 130b. The control layer 140 facilitates adjustment of the radius of curvature of the bending area BA of the flexible substrate 110 and maintains the radius of curvature of the bending area BA at a desired radius of curvature. In one embodiment of the present invention, the radius of curvature means the degree of bending of the curved surface of the bent flexible substrate 110 when the flexible substrate 110 is bent.

The control layer 140 is disposed on a part of the rear surface of one of the plurality of support substrates 130a and 130b, and is disposed on the entire upper surface of the other 130b of the plurality of support substrates 130a and 130b.

The side surface of the control layer 140 adjacent to the bending area BA protrudes toward the bending area BA. The protruding side surface of the control layer 140 is a virtual side surface of the control layer 140 connecting each side of the plurality of supporting substrates 130a and 130b adjacent to the bending area BA of the flexible substrate 110. It means that it extends toward the bending area BA side rather than the straight line A-A'. The control layer 140 protruding from the side toward the bending area BA reduces the deflection or warpage of the bent non-display unit NP.

The control layer 140 may have a circular or elliptical shape. A portion of the control layer 140 including a circular or elliptical shape has a curved side. A part of the side surface of the control layer 140 is positioned to contact the bending area BA of the bent flexible substrate 110 to support the bent non-display unit NA. The control layer 140 generally has a thickness of 200 μm to 400 μm. Since some side surfaces of the control layer 140 are in contact with the bending area BA, the bending area BA of the bent flexible substrate 110 may have a constant radius of curvature.

In addition, a part of the control layer 140 including a circular or elliptical shape protrudes in the direction of the bending area BA rather than an imaginary straight line AA' connecting each side of the plurality of support substrates 130a and 130b to each other. Can be located. Accordingly, when the bending flexible substrate 110 of the flexible organic light emitting diode display 100 moves by an external environment, damage to the bending area BA of the flexible substrate 110 can be minimized.

A part of the control layer 140 that protrudes more in the direction of the bending area BA than the imaginary straight line AA' connecting each side of the plurality of support substrates 130a and 130b to each other, and includes a circular or elliptical shape. The size of the bending area BA can be adjusted according to the position.

The control layer 140 may have a hook shape or a mushroom shape. The control layer 140 may be made of stainless steel (SUS), polyethylene terephthalate (PET), or polycarbonate (PC), but is not limited thereto.

According to an embodiment of the present invention, the control layer is preferably made of polycarbonate (PC) having low stress.

In general, when an external load acts on an object, a stress, which is a resistance to the external load, occurs in the object in proportion to the load. Therefore, the control layer 140 also has this stress. In particular, stainless steel (SUS) used as the control layer 140 has a greater stress than polycarbonate (PC). The stress may stress the flexible substrate 110 of the flexible display device 100. Due to the stress, wrinkles may be generated in a portion of the flexible substrate 110.

1 and 2, in one embodiment of the present invention, the stress absorbing layer 150 that contacts one surface of the plurality of support substrates 130a and 130b and minimizes the stress of the control layer 140 is flexible organic It is included in the light emitting display device 100. The stress absorbing layer 150 is positioned between one support substrate 130a and the control layer 140 contacting the display portion DP of the flexible substrate 110 among the plurality of support substrates 130a and 130b. The stress absorbing layer 150 is composed of a plurality of layers, and may be formed in a structure in which the adhesive resin layer 150a, the cushion layer 150b, and the adhesive resin layer 150a are stacked. The cushion layer 150b of the stress absorbing layer 150 serves to absorb stress generated in the control layer 140.

As the cushion layer 150b, an organic material having excellent absorption function may be used, and for example, polyolefin may be used. The thickness of the stress absorbing layer 150 is 150 μm to 200 μm. When the control layer 140 has a hook shape, the thickness of the stress absorbing layer 150 is preferably equal to or smaller than the height of a portion of the control layer 140 having a hook shape. When the thickness of the stress absorbing layer 150 is greater than the height of the portion of the control layer 140 having a hook shape, the radius of curvature of the bent flexible substrate 110 may be large. As a result, the size of the flexible organic light emitting diode display 100 may be increased. The adhesive resin layer 150a may improve the degree of adhesion between the control layer 140 and the cushion layer 150b. OCR (Optical Clear Resin) may be used as the adhesive resin layer 150a.

Therefore, in the present embodiment, the stress absorbing layer 150 may minimize wrinkles generated in some regions of the flexible substrate 110 in a position corresponding to the control layer 140 due to the stress of the control layer 140. In addition, the stress absorbing layer 150 is closely positioned with the same thickness as the hook shape of the control layer 140, so that the size of the flexible organic light emitting display device 100 may be reduced.

Table 1 is a table for explaining stress in an edge region when a flexible substrate of various materials is bent using a stress absorbing layer and when a flexible substrate is bent without using a stress absorbing layer. The first row of the table is a row showing the material of the flexible substrate and whether a stress absorbing layer is used, and the second row is a photograph illustrating the stress according to the position of the flexible substrate when the flexible substrate is bent, and the third row is an edge area ( This is a row showing the magnitude and relative percentage of stress generated in the square part in the photo).

[Table 1]

Referring to Table 1, it can be seen that the stress generated on the flexible substrate 110 of the flexible organic light emitting diode display 100 according to an embodiment of the present invention is greatly improved. When polycarbonate (PC) is used as the control layer 140 and the stress absorbing layer 150 is included in the flexible organic light emitting diode display 100 (rightmost in Table 1), stress generated in the flexible substrate 110 is controlled. It is confirmed that the stainless steel (SUS) is significantly lower than that of 140 when used. When polycarbonate (PC) is used as the control layer (leftmost in Table 1), assuming 100% of the stress generated on the flexible substrate, stainless steel (SUS) is used as the control layer 140 and the stress absorbing layer 150 is flexible. When included in the organic light emitting display device 100 (in the middle of Table 1), the stress generated on the flexible substrate is 17.4%, polycarbonate (PC) is used as the control layer 140, and the stress absorbing layer 150 is a flexible organic light emitting display When included in the device 100 (rightmost in Table 1), the stress generated on the flexible substrate is only 1.2%. Therefore, it can be seen through Table 1 that the stress absorbing layer 150 minimizes the stress generated in the flexible substrate 110 by almost absorbing the stress of the control layer 140.

3A and 3B are schematic cross-sectional views for describing a shape of a control layer of an organic light emitting diode display according to various embodiments of the present invention. 3A and 3B show only the control layers 340A and 340B, the stress absorbing layer 350 and the adhesive layer 360 among various elements of the organic light emitting display device for convenience of description. The stress absorbing layer 350 and the adhesive layer 360 of FIGS. 3A and 3B are substantially the same as the stress absorbing layer 150 and the adhesive layer 160 of FIGS. 1 and 2.

First, referring to FIG. 3A, the control layer 340A is a head portion 342A protruding from the base portion 341A, the base portion 341A, which is in contact with the stress absorbing layer 350, and in contact with the bent non-display portion of the flexible substrate. And a connecting portion 343A connecting the base portion 341A and the head portion 342A. Although the flexible substrate is not illustrated in FIG. 3A, as shown in FIG. 1, the head portion 342A may contact the bent non-display portion of the flexible substrate. The base portion 341A has a flat upper and lower surfaces, a stress absorbing layer 350 is disposed on the upper surface of the base portion 341A, and an adhesive layer 360 is disposed on the lower surface of the base portion 341A. The head portion 342A is formed in a semi-circular shape or a semi-elliptical shape.

The connection portion 343A connects the top end of the head portion 342A and the base portion 341A. At this time, as illustrated in FIG. 3A, the outer surface of the connecting portion 343A connecting the top end of the head portion 342A and the base portion 341A may be curved. That is, on the cross-section cut in the direction perpendicular to the upper surface of the base portion 341A, the connection portion 343A connecting the top end of the head portion 342A and the base portion 341A has a curved shape.

Next, referring to FIG. 3B, the connection portion 343B of the control layer 340B connects the top end of the head portion 342B and the base portion 341B. At this time, as shown in FIG. 3B, the outer surface of the connecting portion 343B connecting the top end of the head portion 342B and the base portion 341B may be curved. That is, on the cross-section cut in the direction perpendicular to the upper surface of the base portion 341B, the connecting portion 343B connecting the top end of the head portion 342B and the base portion 341B has a diagonal shape. The base portion 341B and the head portion 342B of the control layer 340B are substantially the same as the base portion 341A and the head portion 342A of the control layer 340A shown in FIG. 3A.

When the control layers 340A, 340B having the connecting portions 343A, 343B having the shape as described above are used, the connecting portions 343A, 343B may serve as a support for the head portions 342A, 342B, thereby Accordingly, the improved control layer 340A rigidity can be secured.

4 is a schematic cross-sectional view for describing a flexible organic light emitting display device including a circuit board and a system unit according to an embodiment of the present invention.

Referring to FIG. 4, the flexible organic light emitting diode display 400 includes a flexible substrate 410, an organic light emitting device 420, a plurality of support substrates 430a and 430b, a bezel area control layer 440, and an adhesive layer 460. , 1st stress distribution layer 450a, 2nd stress distribution layer 450b driving element 480, insulating film 470, driving element cover 481, system part 490, circuit board 492, and step And a compensation layer 491. The flexible substrate 410 of FIG. 4, the organic light emitting device 420, the plurality of support substrates 430a and 430b, the bezel region control layer 440, the adhesive layer 460, and the first stress distribution layer 450a are illustrated in FIG. 1 The flexible substrate 110, the organic light emitting device 120, a plurality of support substrates (130a, 130b), the control layer 140, the adhesive layer 160 and the stress absorbing layer 150 is substantially the same. In addition, the display unit DP and the non-display unit DP of FIG. 4 are also substantially the same as the display unit DP and the non-display unit NP of FIG. 1.

Referring to FIG. 4, the first stress dispersing layer 450a is located on the rear surface of a portion of one of the support substrates 430a among the plurality of support substrates 430a and 330b corresponding to the display portion DP of the flexible substrate 410 do. The first stress distribution layer 450a fixes the support substrate 430a and the bezel region control layer 440. The first stress distribution layer 450a may minimize stress generated in a portion of the flexible substrate 410 corresponding to the bezel region control layer 440 by the stress of the bezel region control layer 440.

The flexible substrate 410 includes a bezel area BZA. When the viewer views the image through the flexible organic light emitting diode display 400, the bezel area BZA refers to a border portion in which the image is not displayed. The bezel region control layer 440 has a thickness of 300 μm to 500 μm. In addition, a portion of the bezel area control layer 440 is formed in a hook shape. The bezel region control layer 440 may adjust the bezel region BZA in the above-described thickness and shape, and for example, bezel regions BZA, such as the width and area of the bezel region BZA, may be variously adjusted. The bezel area BZA is a portion of the flexible substrate 410 bent.

An insulating film 470 is attached to a portion of the non-display portion DP of the flexible substrate 410. A driving element 480 that generates and transmits a driving signal for driving the display portion of the flexible substrate 410 is positioned on the insulating film 470. An anisotropic conductive film (ACF) or a chip-on film (COF) may be used as the insulating film 470. The insulating film 470 may include circuit wiring that transmits a driving signal from the driving element 480 to the flexible substrate 410.

A circuit board 492 electrically connected to the insulating film 470 is disposed. A system unit 490 that supplies signals and driving voltages required to the driving element 480 is located on the circuit board 492.

The system unit 490 may include a processor such as a timing controller, a sensor, and a power supply. The system unit 490 is positioned corresponding to a portion of the display unit DP of the flexible substrate 410. The system unit 490 has a constant thickness and area.

Accordingly, when the system unit 490 is positioned on the rear surface of the flexible substrate 410, it affects the thickness of the flexible organic light emitting display device 410 together with the driving element 480 positioned on the insulating film 470. And, when an external load acts on the system unit 490, a stress, which is a resistance to an external load, occurs in the system unit 490 in proportion to the load. As described above, the stress generated in the system unit 490 causes stress to the flexible substrate 410.

In the flexible organic light emitting diode display 410 according to an exemplary embodiment of the present invention, a part of the system unit 490 is patterned in a groove shape, and the driving element 480 is positioned on the patterned portion, so that the organic light emitting diode display 410 The thickness of the can be optimized.

The driving element cover layer 481 is disposed on the driving element 480 located in a portion of the patterned system unit 490. When the flexible organic light emitting diode display 410 moves due to an external environment, the driving element cover layer 481 is damaged from damage that may occur when the driving element 480 contacts the plurality of support substrates 430a and 330b. It is a cover layer for protecting the driving element 480.

In addition, in the flexible organic light emitting diode display 410 according to an exemplary embodiment of the present invention, the second stress distribution layer 450b for dispersing stress included in the system unit 490 includes a plurality of support substrates 430a and 430b. ) Between the support substrate 430a and the system unit 490. The second stress distribution layer 450b is formed in a shape corresponding to the shape of the partially patterned system portion 490. That is, the second stress distribution layer 450b is also partially patterned like the system unit 490. The second stress distribution layer 450b is substantially the same structure as the stress absorption layer 150 of FIG. 2. The second stress distribution layer 450b may be formed of a plurality of layers including a foam film. Accordingly, the second stress distribution layer 450b disperses stress generated in a part of the flexible substrate 410 corresponding to the system unit 490 due to the stress of the system unit 490.

Referring to FIG. 4, in the flexible organic light emitting diode display 410 according to an exemplary embodiment of the present invention, a step compensation layer 491 is positioned between the system unit 490 and the circuit board 492. Due to the difference in thickness between the bezel region control layer 440 and the system unit 480, the thickness d2 of the flexible organic light emitting display device 410 on which the bezel region control layer 440 is located and the system unit 480 are located. A difference occurs between the thicknesses d1 of the flexible organic light emitting display device 410. The above-described difference in thickness may degrade the adhesive strength of the insulating substrate adhered to the flexible substrate 410 and the circuit substrate adhered to the insulating substrate. The step compensation layer 491 functions as a compensation layer capable of improving adhesion between the insulating substrate and the circuit substrate by compensating for the above-described thickness difference.

5 is a flowchart illustrating a method of manufacturing a flexible organic light emitting display device according to an embodiment of the present invention.

First, a plurality of support substrates spaced apart from each other is disposed on a flexible substrate including a display unit and a non-display unit (S50).

The flexible substrate may be made of a material selected from the group consisting of a polyester polymer, a silicone polymer, an acrylic polymer, a polyolefin polymer, and combinations thereof, which are bendable materials. Specifically, the flexible substrate is polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polysilane, polysiloxane, polysilazane, polycarbosilane, polyacrylate (polyacrylate), polymethacrylate, polymethylacrylate, polyethylacrylate, polyethylmethacrylate, cyclic olefin copolymer (COC), cyclic olefin Polymer (COP), polyethylene (PE), polypropylene (PP), polyimide (PI), polymethyl methacrylate (PMMA), polystyrene (PS), polyacetal (POM), polyether ether ketone (PEEK), Polyester sulfone (PES), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycarbonate (PC), polyvinylidene fluoride (PVDF), perfluoroalkyl polymer (PFA), styrene acrylic Nitrile copolymer (SAN) and a combination thereof. However, it is not necessarily limited to this.

An insulating film on which a driving element is mounted may be connected to a non-display portion of the flexible substrate, and a circuit board may be connected to the insulating film.

The plurality of support substrates may be formed of substantially the same material as the flexible substrate, but may have a relatively thick thickness. Each of the plurality of supporting substrates may be disposed simultaneously or sequentially.

Then, a stress absorbing layer is formed on a part of the plurality of supporting substrates (S51).

The stress absorbing layer has a structure of a bonding layer, a cushion layer, and a bonding layer, and is formed in the order of the bonding layer, the cushion layer and the bonding layer.

The cushion layer of the stress absorbing layer may be made of polyolefin, but is not limited thereto.

Subsequently, a control layer for controlling the bending radius of the flexible substrate is disposed on the stress absorbing layer (S52).

The control layer may be made of stainless steel (SUS), polyethylene terephthalate (PET), or polycarbonate (PC), but is not limited thereto. A portion of the control layer may be hook-shaped.

Next, the flexible substrate is bent so that the non-display portion of the flexible substrate faces at least a portion of the display portion of the flexible substrate (S53).

Bending the flexible substrate is such that the non-display portion of the flexible substrate positioned on the same plane as the display portion of the flexible substrate is positioned on another plane parallel to the display portion of the flexible substrate through a direction perpendicular to the display portion of the flexible substrate. it means. When the flexible substrate is bent, the display portion and the non-display portion of the flexible substrate are opposed to each other, and a curved bending portion is formed between the display portion and the non-display portion of the flexible substrate. As the flexible substrate is bent, one of the plurality of support substrates disposed on the non-display portion of the flexible substrate is disposed on the rear surface of the control layer.

The embodiments of the present invention have been described in more detail with reference to the accompanying drawings, but the present invention is not necessarily limited to these embodiments, and may be variously modified without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of protection of the present invention should be interpreted by the claims below, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

100, 400: flexible organic light emitting display device
110, 410: flexible substrate
120, 420: organic light emitting device
130, 130a, 130b, 430, 430a, 430b: support substrate
140, 340A, 340B: control layer
341A, 341B: Base section
342A, 342B: head
343A; 343B: Connection
150, 350: stress absorbing layer
150a, 350a: adhesive resin layer
150b, 350b: cushion layer
160, 360, 460: adhesive layer
440: bezel area control layer
450: stress distribution layer
450a: first stress distribution layer
450b: second stress dispersion layer
470: insulating film
480: driving element
481: driving element cover
490: system unit
491: step compensation layer
492: circuit board

Claims (1)

A flexible substrate including a display unit displaying an image and a non-display unit extending from one side of the display unit and bending;
A plurality of support substrates positioned on the flexible substrate and spaced apart from each other to easily bend the flexible substrate;
A control layer positioned between the plurality of supporting substrates and controlling a bending radius of the flexible substrate; And
Located on one surface of the control layer and includes a stress absorbing layer for absorbing the stress generated in the control layer,
The stress absorbing layer is characterized in that it minimizes the occurrence of wrinkles in the flexible substrate region at a position corresponding to the control layer, the flexible display device.

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