Display device

Abstract

A display device has non-foldable areas and a foldable area between the non-foldable areas. The display device includes: a display module; a plate supporting the display module under the display module, the plate defining a plurality of opening patterns overlapping the foldable area; a first adhesive layer interposed between the display module and the plate and overlapping at least the non-foldable area; and a polyolefin-based resin filling the plurality of opening patterns.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0000269, filed with the Korean Intellectual Property Office on January 2, 2024, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to a display device. Background Art

[0004] Unlike a rigid display device, a foldable display device can be bent, folded, or rolled up. Accordingly, a foldable display device can be easily carried in a compact configuration and is more convenient for a user. However, as a foldable display device is repeatedly used, creases may be generated in a certain region (e.g., a foldable region), and the shape of the foldable display device may be deformed. The creases or deformation may cause deterioration in visibility of an image in the display device and may damage the appearance of the display device. Summary of the Invention

[0005] Embodiments disclosed herein include a display device having improved visibility and a method of manufacturing a display device.

[0006] According to an aspect of the present disclosure, a display device may include a non-foldable region and a foldable region disposed between the non-foldable regions. The display device may specifically include: a display module; a plate supporting the display module under the display module, the plate defining a plurality of opening patterns overlapping the foldable region; a first adhesive layer interposed between the display module and the plate; and a polyolefin resin filling the plurality of opening patterns.

[0007] The polyolefin resin may have a melting point of 100°C or higher and 180°C or lower.

[0008] The polyolefin resin may be a linear low density polyethylene (LLDPE) resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins.

[0009] The first adhesive layer may overlap the non-foldable region and may not overlap the foldable region.

[0010] The display device may further include a step difference compensation layer disposed on the plate in the foldable region and covering the polyolefin resin filling the plurality of opening patterns.

[0011] The step difference compensation layer may include a metal layer and a cover layer disposed on the metal layer.

[0012] The display module may include: a protective film layer; a panel layer disposed on the protective film layer, the panel layer including a plurality of pixels; and a second adhesive layer interposed between the protective film layer and the panel layer.

[0013] The first adhesive layer may be in direct contact with each of the protective film layer and the plate in the non-foldable region.

[0014] The thickness of the display module may be 80 μm or greater and 120 μm or less.

[0015] According to another aspect of the present disclosure, a display device may have a non-foldable region and a foldable region disposed between the non-foldable regions. The display device may include: a display module; a plate supporting the display module below the display module, the plate defining a plurality of opening patterns overlapping the foldable region; a first adhesive layer interposed between the display module and the plate; and a polyolefin resin filling the plurality of opening patterns. The first adhesive layer may overlap the non-foldable region and the foldable region.

[0016] The melting point of the polyolefin resin may be 100 °C or higher and 180 °C or lower.

[0017] The polyolefin resin may be a linear low-density polyethylene (LLDPE) resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins.

[0018] The display module may include: a protective film layer; a panel layer disposed on the protective film layer, the panel layer including a plurality of pixels; and a second adhesive layer interposed between the protective film layer and the panel layer.

[0019] The first adhesive layer may be in direct contact with each of the protective film layer and the plate in the non-foldable region and the foldable region.

[0020] The thickness of the display module may be 80 μm or greater and 120 μm or less.

[0021] According to another aspect of the present disclosure, a method of manufacturing a display device, the display device including a non-foldable region and a foldable region disposed between the non-foldable regions, the method of manufacturing the display device may include: filling a polyolefin resin in a plurality of opening patterns defined in the plate to overlap the foldable region; and attaching the plate to the display module by interposing a first adhesive layer between the plate and the display module. The filling may include pressing together the plate and a structure including the polyolefin resin and a step difference compensation layer disposed on the polyolefin resin, and the pressing may use a pair of pressing plates.

[0022] During the pressing, the structure may not overlap the non-foldable region and may overlap the foldable region.

[0023] The method may further include removing the step difference compensation layer after pressing the plate and the structure together.

[0024] The melting point of the polyolefin resin may be 100 °C or higher and 180 °C or lower.

[0025] The pressing may be performed at a temperature equal to or higher than the melting point of the polyolefin resin.

[0026] The polyolefin resin may be a linear low density polyethylene (LLDPE) resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Example embodiments will be described more fully hereinafter with reference to the accompanying drawings. In the drawings, for clarity of illustration, the dimensions may be exaggerated or otherwise modified. The same reference numerals always denote the same elements.

[0028] Figure 1 and Figure 2 are perspective views respectively showing a planar configuration and a folded configuration of a display device according to an embodiment of the present disclosure.

[0029] Figure 3 is according to Figure 1 a cross-sectional view taken along line I-I' of the first embodiment of the display device shown in

[0030] Figure 4 is according to Figure 1 a cross-sectional view taken along line I-I' of the second embodiment of the display device shown in

[0031] Figure 5 is according to Figure 1 a cross-sectional view taken along line I-I' of the third embodiment of the display device shown in

[0032] Figure 6 is according to Figure 1 a cross-sectional view taken along line I-I' of the fourth embodiment of the display device shown in

[0033] Figure 7 is according to Figure 1 a cross-sectional view taken along line I-I' of the fifth embodiment of the display device shown in

[0034] Figure 8 is according to Figure 1 a cross-sectional view taken along line I-I' of the sixth embodiment of the display device shown in

[0035] Figure 9 is according to Figure 1A cross-sectional view taken along line I-I' of a seventh embodiment of the display device shown in

[0036] Figure 10 is according to Figure 1 A cross-sectional view taken along line I-I' of an eighth embodiment of the display device shown in

[0037] Figure 11 is a flowchart showing a method of manufacturing a display device according to any of the above embodiments.

[0038] Figure 12 、 Figure 13 and Figure 14 are cross-sectional views showing Figure 11 the heating and pressing steps shown in Detailed Description

[0039] Hereinafter, example embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. The following description focuses on components and features necessary for understanding the subject matter of the present disclosure, and descriptions of other components or features may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. In addition, the present disclosure is not limited to the example embodiments described herein, but may be embodied in various different forms. Instead, the example embodiments described herein are provided to convey aspects of the present disclosure to those of ordinary skill in the art.

[0040] Throughout the specification, an element referred to as "connected" or "coupled" to another element may be directly connected or coupled to the other element, or may be indirectly connected or coupled to the other element with one or more intervening elements therebetween. An element referred to as "between" two elements may be the only element between the two elements, or one or more intervening elements may also be present. Unless expressly stated herein, when a component "includes" an element, it should be understood that the component does not exclude another element, but may also include another element. For the purposes of the present disclosure, "at least one of X, Y, and Z" should be construed to mean only X, only Y, only Z, or any combination of two or more of X, Y, and Z (e.g., XYZ, XY, YZ, XZ). Similarly, for the purposes of the present disclosure, "at least one selected from the group consisting of X, Y, and Z" should be construed to mean only X, only Y, only Z, or any combination of two or more of X, Y, and Z (e.g., XYZ, XY, YZ, XZ).

[0041] It will be understood that although terms such as "first", "second", etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, without departing from the teachings of the present disclosure, the "first" element discussed below may also be referred to as the "second" element.

[0042] For ease of description, spatial relative terms such as "below" and "above" may be used herein to describe the relationship of one element to another as shown in the figures. It will be understood that, in addition to the orientations described herein and depicted in the figures, spatial relative terms and the configurations shown are intended to encompass different orientations of the device in use or operation. For example, if the device in the figures is flipped, an element described as "below" or "beneath" other elements or features will then be oriented "above" the other elements or features. Thus, the exemplary term "above" can encompass both the above and below orientations. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and the spatial relative terms used herein are to be interpreted accordingly.

[0043] In addition, embodiments of the present disclosure may be described herein with reference to schematic illustrations of ideal embodiments (and intermediate structures) of the present disclosure, such that variations in the shapes shown can be expected due to, for example, manufacturing techniques and / or tolerances. Accordingly, embodiments of the present disclosure should not be limited to the specific shapes of the regions shown herein, but include shape deviations caused by, for example, manufacturing techniques. The regions and features shown in the figures are schematic in nature. For example, the shapes shown in the figures may not represent the actual shapes of the regions of the device, and the figures are not intended to limit the scope of the present disclosure to the shapes shown.

[0044] Figure 1 and Figure 2 are perspective views respectively showing a planar configuration and a folded configuration of a display device according to an embodiment of the present disclosure. Figure 1 is a perspective view showing the display device in an unfolded state. Figure 2 is a perspective view showing the display device in a folded state.

[0045] Referring to Figure 1 and Figure 2 , the display device 100 may have a display surface DS. As Figure 1 shown, when the display device 100 is in the unfolded state, the display surface DS may be in a plane defined by a first direction DR1 and a second direction DR2.

[0046] The display surface DS may include a display area DA and a non-display area NDA at the periphery of the display area DA. The display area DA is an area where the display device 100 may display an image, and the non-display area NDA may be an area where no image is displayed.

[0047] In Figure 1In an embodiment, the display area DA may have a quadrilateral shape in a plan view. The non-display area NDA may surround at least a part of the display area DA. However, the display area DA and the non-display area NDA are not limited to the shapes shown, and the shapes of each of the display area DA and the non-display area NDA may be variously modified.

[0048] The display device 100 may include a first non-foldable area NFA1, a foldable area FA, and a second non-foldable area NFA2 that are sequentially defined (or arranged) along the second direction DR2 or in a direction opposite to the second direction DR2. For example, the foldable area FA may be disposed between the first non-foldable area NFA1 and the second non-foldable area NFA2. Although Figure 1 and Figure 2 an example showing one foldable area FA and two non-foldable areas NFA1 and NFA2 is shown, the embodiment is not limited thereto. For example, the display device 100 may include two or more non-foldable areas, and the foldable area is disposed between adjacent non-foldable areas.

[0049] The display device 100 may be folded about a folding axis FX. As a result, the foldable area FA may be bent about the folding axis FX. In an example where the non-foldable areas NFA1 and NFA2 are arranged along the second direction DR2, the folding axis FX may extend in the first direction DR1.

[0050] The display surface DS of the display device 100 may be folded inward with respect to the folding axis FX. When the display device 100 is folded as Figure 2 shown, the display surface of the first non-foldable area NFA1 and the display surface of the second non-foldable area NFA2 may face each other. However, the display device 100 of the present disclosure is not limited thereto. For example, the display device 100 may be folded outward with respect to the folding axis FX. When the display device 100 is folded outward, the display surfaces of the first non-foldable area NFA1 and the second non-foldable area NFA2 may face in opposite directions.

[0051] Figure 3 is a cross-sectional view taken along line I-I' of a first embodiment of the display device as shown in Figure 1 shown.

[0052] Refer to Figure 3, the display device 100A according to the first embodiment of the present disclosure may include a board PLT, a first adhesive layer PSA1, a first black primer coating BL1, a barrier layer BRL, a second black primer coating BL2, a second adhesive layer PSA2, a protective film layer PFL, a third adhesive layer PSA3, a panel layer PNL, a fourth adhesive layer PSA4, a functional layer DL, a fifth adhesive layer PSA5, a glass layer UTG, a sixth adhesive layer PSA6, a first protective layer PL, and a second protective layer HCAF.

[0053] The first black primer coating BL1, the barrier layer BRL, the second black primer coating BL2, the second adhesive layer PSA2, the protective film layer PFL, the third adhesive layer PSA3, the panel layer PNL, the fourth adhesive layer PSA4, and the functional layer DL may form a display module DM, and the glass layer UTG, the sixth adhesive layer PSA6, the first protective layer PL, and the second protective layer HCAF may form a window WD.

[0054] The board PLT may include a material having a relatively high hardness. Accordingly, the board PLT may serve to support various components disposed on the board PLT. For example, the board PLT under the display module DM may serve to support the display module DM.

[0055] In an embodiment, a plurality of opening patterns OP in the board PLT may overlap with a foldable region FA. Accordingly, the board PLT may be more flexible in the foldable region FA.

[0056] The first adhesive layer PSA1 may be interposed between the board PLT and the display module DM. For example, as Figure 3 shown, the first adhesive layer PSA1 may be interposed between the board PLT and the first black primer coating BL1. The first adhesive layer PSA1 may serve to bond the board PLT and the display module DM to each other.

[0057] In an embodiment, the first adhesive layer PSA1 may be in direct contact with each of the board PLT and the display module DM. For example, as Figure 3 shown, the first adhesive layer PSA1 may be in direct contact with each of the board PLT and the first black primer coating BL1. In an embodiment where the first black primer coating BL1 is omitted as described below, the first adhesive layer PSA1 may be in direct contact with the board PLT and the barrier layer BRL.

[0058] The first black primer coating BL1, the barrier layer BRL, and the second black primer coating BL2 may be sequentially disposed on the first adhesive layer PSA1. In an embodiment, the first black primer coating BL1 and the second black primer coating BL2 may include black primers coated on the top and bottom surfaces of the barrier layer BRL.

[0059] Each of the first black primer coating BL1 and the second black primer coating BL2 can serve to improve the black visibility in the display device 100A. For example, when the display device 100A does not display any image, the first black primer coating BL1 and the second black primer coating BL2 can make the display area DA (see Figure 1 ) appear black.

[0060] In an alternative embodiment, at least one of the first black primer coating BL1 and the second black primer coating BL2 can be omitted.

[0061] The barrier layer BRL can serve to absorb and reduce the impact from the bottom surface of the display device 100A. In an embodiment, the barrier layer BRL can include an organic insulating material. The barrier layer BRL can be designated as a buffer layer.

[0062] The protective film layer PFL can be disposed on the second black primer coating BL2, and the second adhesive layer PSA2 can be interposed between the second black primer coating BL2 and the protective film layer PFL.

[0063] The protective film layer PFL can be under the panel layer PNL and can serve to absorb and reduce the impact from the bottom of the panel layer PNL. In addition, the protective film layer PFL can serve to block the penetration of impurities toward the bottom surface of the panel layer PNL.

[0064] The second adhesive layer PSA2 can serve to bond the second black primer coating BL2 and the protective film layer PFL to each other. In an embodiment, the second adhesive layer PSA2 can be in direct contact with each of the second black primer coating BL2 and the protective film layer PFL.

[0065] The panel layer PNL can be disposed on the protective film layer PFL, and the third adhesive layer PSA3 can be interposed between the protective film layer PFL and the panel layer PNL.

[0066] The panel layer PNL can include a plurality of pixels PX. Each of the pixels PX can emit light, and the display device 100A can display an image formed by a combination of the light emitted from the plurality of pixels PX.

[0067] The third adhesive layer PSA3 can serve to bond the protective film layer PFL and the panel layer PNL to each other. In an embodiment, the third adhesive layer PSA3 can be in direct contact with each of the protective film layer PFL and the panel layer PNL.

[0068] The functional layer DL can be disposed on the panel layer PNL, and the fourth adhesive layer PSA4 can be interposed between the panel layer PNL and the functional layer DL.

[0069] The functional layer DL may include one or more layers. For example, the functional layer DL may be a film layer that basically performs the same function as the protective film layer PFL. In another example, the functional layer DL may be a polarizing layer that prevents external light incident from the outside of the display device 100A from being reflected and then being seen by the user. In still another example, the functional layer DL may have a stacked structure of a film layer and a polarizing layer. In an embodiment, the functional layer DL may be omitted. The fourth adhesive layer PSA4 is provided to bond the panel layer PNL and the functional layer DL to each other, but in some embodiments, the fourth adhesive layer PSA4 may be omitted.

[0070] The glass layer UTG may be provided on the functional layer DL, and the fifth adhesive layer PSA5 may be interposed between the glass layer UTG and the functional layer DL.

[0071] The glass layer UTG may include a material having a relatively high light transmittance and a relatively high hardness. In addition, the glass layer UTG may be flexible. For example, the glass layer UTG may include ultra-thin reinforced glass.

[0072] The fifth adhesive layer PSA5 may serve to bond the functional layer DL and the glass layer UTG to each other. In an embodiment, the fifth adhesive layer PSA5 may be in direct contact with each of the functional layer DL and the glass layer UTG.

[0073] The first protective layer PL may be provided on the glass layer UTG, and the sixth adhesive layer PSA6 may be interposed between the glass layer UTG and the first protective layer PL.

[0074] The first protective layer PL may have a relatively high light transmittance and may include a material having sufficient hardness to protect the underlying structure. In addition, the first protective layer PL may be flexible. For example, the first protective layer PL may include polyethylene terephthalate (PET). The first protective layer PL together with the glass layer UTG may perform the function of protecting the display device 100A from external impacts.

[0075] The sixth adhesive layer PSA6 may serve to bond the glass layer UTG and the first protective layer PL to each other. In an embodiment, the sixth adhesive layer PSA6 may be in direct contact with each of the glass layer UTG and the first protective layer PL.

[0076] The second protective layer HCAF may be provided on the first protective layer PL. In an embodiment, the second protective layer HCAF may be a coating applied on the first protective layer PL. The second protective layer HCAF may prevent or resist the formation of marks (such as fingerprints, etc.) caused by the user's touch.

[0077] In the above-described display device 100A according to the first embodiment of the present disclosure, the polyolefin resin POR may fill a plurality of opening patterns OP defined in the plate PLT. The polyolefin resin POR may serve to improve the reliability of the plate PLT in the foldable region FA. Specifically, if the polyolefin resin POR is omitted, after repeated shape deformation or folding in the foldable region FA, the plate PLT may sag in the foldable region FA in a direction opposite to the third direction DR3 (see Figure 1 ). Repeated folding causes sagging of the display module DM in the foldable region FA, which is a problem that may generate creases. In the example of Figure 3 , the polyolefin resin POR filling the plurality of opening patterns OP may minimize the sagging of the plate PLT in the foldable region FA.

[0078] In an embodiment, the melting point of the polyolefin resin POR may be about 100 °C or higher to about 180 °C or lower, preferably about 130 °C or higher to about 150 °C or lower. When the melting point of the polyolefin resin POR is within the above temperature range, the reliability of the polyolefin resin POR can be maintained even if the operation of the display device 100A may increase the temperature of the display device 100A. In addition, the temperature required in the process of forming the polyolefin resin POR described below can be relatively low, and thus the manufacturing efficiency can be improved.

[0079] In an embodiment, the polyolefin resin POR may be a linear low-density polyethylene (LLDPE) resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins. More specifically, the linear low-density polyethylene (LLDPE) resin may be made of a polymer having a main chain including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins and side chains of C2 to C6 (preferably, C2 to C3), and having a density of about 0.915 g / cm 3 or greater and about 0.935 g / cm 3 or less. Compared with the density of the high-density polyethylene (HDPE) resin (density: about 0.94 g / cm 3 or greater and about 0.966 g / cm 3Compared with (or less than), linear low density polyethylene (LLDPE) resin can have a relatively low density, and linear low density polyethylene (LLDPE) resin can have a linear molecular structure compared to low density polyethylene (LDPE) resin (resin made from polymers having a crosslinked structure and / or side chains of C7 or more). Meanwhile, various resins previously known in the art can be used as linear low density polyethylene (LLDPE) resin without limitation. When compared with high density polyethylene (HDPE) resin and low density polyethylene (LDPE) resin, linear low density polyethylene (LLDPE) resin has excellent tensile strength, elongation, impact strength, moisture resistance, heat resistance and compressive resistance. Therefore, when linear low density polyethylene (LLDPE) resin is used as the polyolefin resin POR, the reliability of the polyolefin resin POR can be sufficiently ensured despite repeated shape deformations in the foldable region FA.

[0080] In an embodiment, the first adhesive layer PSA1 can overlap with the first non-foldable region NFA1 and the second non-foldable region NFA2. In addition, the first adhesive layer PSA1 can overlap with the foldable region FA. That is, the first adhesive layer PSA1 can completely cover the first non-foldable region NFA1, the foldable region FA and the second non-foldable region NFA2.

[0081] The first adhesive layer PSA1 can cover the polyolefin resin POR filling a plurality of opening patterns OP defined in the foldable region FA. That is, in the foldable region FA, there may be no empty space between the plate PLT and the display module DM. Therefore, although the folding and unfolding of the display device 100A may cause repeated shape deformations, the support of the display module DM in the foldable region FA can sufficiently prevent or minimize the generation of creases in the foldable region FA (or regions adjacent thereto).

[0082] Figure 4 is a cross-sectional view taken along line I-I' of a second embodiment of the display device shown in Figure 1

[0083] Referring to Figure 4 , the display device 100B according to the second embodiment of the present disclosure can be substantially the same as the display device 100A according to the first embodiment of the present disclosure already described with reference to Figure 3 . Therefore, a repeated description of components identical to those described above with reference to Figure 4 can be omitted from the following description of Figure 3

[0084] The first adhesive layer PSA1 in the display device 100B is different from the first adhesive layer PSA1 in the display device 100A. In the display device 100B according to the second embodiment of the present disclosure, the first adhesive layer PSA1 may overlap with the non-foldable regions NFA1 and NFA2 and may not overlap with the foldable region FA.

[0085] Since the first adhesive layer PSA1 does not overlap with the foldable region FA, the display module DM and the board PLT can be spaced apart from each other in the foldable region FA, and there may be a gap in the foldable region FA between the display module DM and the board PLT. That is, the portion of the board PLT that defines the plurality of opening patterns OP in the foldable region FA may be spaced apart from the overlying portion of the display module DM. Although the shape of the display device 100B may be repeatedly deformed in the foldable region FA, or the display device 100B may be subjected to an impact applied from the outside of the display device 100B, the portions of the display module DM and the board PLT that define the plurality of opening patterns OP may be substantially non-contact with each other. Therefore, it is possible to prevent the formation or imprinting of concavo-convex patterns corresponding to the plurality of opening patterns OP in the display module DM.

[0086] Figure 5 is a cross-sectional view taken along line I-I' of a third embodiment of the display device as shown in Figure 1 .

[0087] Referring to Figure 5 , the display device 100C according to the third embodiment of the present disclosure may be substantially the same as the display device 100B according to the second embodiment of the present disclosure that has been described with reference to Figure 4 . Therefore, the repeated description of the components that are shown in Figure 5 but are the same as the components already described above may be omitted hereinafter.

[0088] The display device 100C is different from the display device 100B in that the display device 100C further includes a step difference compensation layer SCL. In the display device 100C according to the third embodiment of the present disclosure, the step difference compensation layer SCL may be provided on the board PLT in the foldable region FA and may cover the polyolefin resin POR that fills the plurality of opening patterns OP.

[0089] The step-difference compensation layer SCL can at least partially compensate for the step difference under the display module DM, which is caused by the lack of the first adhesive layer PSA1 in the foldable area FA on the board PLT. Specifically, if the part of the display module DM overlapping with the step difference sags, then the step-difference compensation layer SCL can support the sagging part of the display module DM. Therefore, the sag can be controlled and limited, and creases caused by the sag of the display module DM in the foldable area FA can be effectively prevented.

[0090] In an embodiment, the step-difference compensation layer SCL can include a metal layer ML. The step-difference compensation layer SCL can have a single-layer structure including the metal layer ML. For example, the metal layer ML can include aluminum.

[0091] Figure 6 is according to Figure 1 a cross-sectional view taken along line I-I' of a fourth embodiment of the display device shown in

[0092] Referring to Figure 6 , the display device 100D according to the fourth embodiment of the present disclosure can be substantially the same as the display device 100C according to the third embodiment of the present disclosure that has been described with reference to Figure 5 . Therefore, the repeated description of the components that are the same as those already described above can be omitted hereinafter.

[0093] The display device 100D is different from the display device 100C in that the step-difference compensation layer SCL in the display device 100D further includes a cover layer CVL. In Figure 6 an embodiment, the step-difference compensation layer SCL can include a metal layer ML and a cover layer CVL on the metal layer ML. The cover layer CVL can increase the thickness of the step-difference compensation layer SCL and can be made of a material that improves the ability of the step-difference compensation layer SCL to support the display module DM. Therefore, the step-difference compensation layer SCL can more effectively compensate for the step difference caused by the non-overlap of the first adhesive layer PSA1 with the foldable area FA on the board PLT.

[0094] Figure 7 is according to Figure 1 a cross-sectional view taken along line I-I' of a fifth embodiment of the display device shown in

[0095] Referring to Figure 7, the display device 100E according to the fifth embodiment of the present disclosure may include a board PLT', a first adhesive layer PSA1', a protective film layer PFL', a second adhesive layer PSA2', a panel layer PNL', a third adhesive layer PSA3', a glass layer UTG', a fourth adhesive layer PSA4', a first protective layer PL', and a second protective layer HCAF'. The protective film layer PFL', the second adhesive layer PSA2', and the panel layer PNL' may form a display module DM', and the glass layer UTG', the fourth adhesive layer PSA4', the first protective layer PL', and the second protective layer HCAF' may form a window WD'.

[0096] The board PLT' may include a material having a relatively high hardness. Accordingly, the board PLT' may serve to support various components disposed on the board PLT'. For example, the board PLT' may serve to support the display module DM' under the display module DM'.

[0097] In an embodiment, the board PLT' may define a plurality of opening patterns OP' overlapping with the foldable region FA. Accordingly, the board PLT' in the foldable region FA may be more flexible than the board PLT' in the first non-foldable region NFA1 and the second non-foldable region NFA2.

[0098] The first adhesive layer PSA1' may be interposed between the board PLT' and the display module DM'. For example, as shown in Figure 7 , the first adhesive layer PSA1' may be interposed between the board PLT' and the protective film layer PFL'. The first adhesive layer PSA1' may bond the board PLT' and the display module DM' to each other.

[0099] In an embodiment, the first adhesive layer PSA1' may be in direct contact with each of the board PLT' and the display module DM'. For example, as shown in Figure 7 , the first adhesive layer PSA1' may be in direct contact with the board PLT' and the protective film layer PFL'.

[0100] The protective film layer PFL' may be on the first adhesive layer PSA1'. The protective film layer PFL' may be under the panel layer PNL' and may absorb and reduce the impact on the bottom of the panel layer PNL'. In addition, the protective film layer PFL' may also block the penetration of impurities toward the bottom surface of the panel layer PNL'.

[0101] The panel layer PNL' may be on the protective film layer PFL', and the second adhesive layer PSA2' may be interposed between the protective film layer PFL' and the panel layer PNL'.

[0102] The panel layer PNL' may include a plurality of pixels PX. Each of the plurality of pixels PX may emit light, and the display device 100E may display an image formed by a combination of the light emitted from the plurality of pixels PX.

[0103] The second adhesive layer PSA2' may bond the protective film layer PFL' and the panel layer PNL' to each other. In an embodiment, the second adhesive layer PSA2' may be in direct contact with each of the protective film layer PFL' and the panel layer PNL'.

[0104] The glass layer UTG' may be disposed on the panel layer PNL', and the third adhesive layer PSA3' may be interposed between the glass layer UTG' and the panel layer PNL'.

[0105] The glass layer UTG' may include a material having a relatively high light transmittance and a relatively high hardness. In addition, the glass layer UTG' may be flexible. For example, the glass layer UTG' may include ultra-thin reinforced glass.

[0106] The third adhesive layer PSA3' may bond the panel layer PNL' and the glass layer UTG' to each other. In an embodiment, the third adhesive layer PSA3' may be in direct contact with each of the panel layer PNL' and the glass layer UTG'.

[0107] The first protective layer PL' may be disposed on the glass layer UTG', and the fourth adhesive layer PSA4' may be in direct contact with each of the glass layer UTG' and the first protective layer PL'.

[0108] The first protective layer PL' may have a relatively high light transmittance and may include a material having sufficient hardness to protect the underlying structure. In addition, the first protective layer PL' may be flexible. For example, the first protective layer PL' may include polyethylene terephthalate (PET). The first protective layer PL' may protect the display device 100E from external impacts.

[0109] The fourth adhesive layer PSA4' may bond the glass layer UTG' and the first protective layer PL' to each other. In an embodiment, the fourth adhesive layer PSA4' may be in direct contact with each of the glass layer UTG' and the first protective layer PL'.

[0110] The second protective layer HCAF' may be disposed on the first protective layer PL'. In an embodiment, the second protective layer HCAF' may be a coating applied on the first protective layer PL'. The second protective layer HCAF' may prevent or resist the formation of marks (e.g., fingerprints, etc.) caused by a user's touch.

[0111] The above-described display device 100E according to the fifth embodiment of the present disclosure may be one in which theFigure 3 A display device including some components in the display device 100A according to the first embodiment of the present disclosure. For example, the display device 100E does not include the barrier layer BRL, the first black primer coating BL1, the second black primer coating BL2, the functional layer DL, etc. described with reference to Figure 3 Therefore, the display device 100E can have a thickness thinner than that of the display device 100A in the third direction DR3. For example, in the display device 100E, the thickness of the display module DM' in the third direction DR3 can be about 80 μm or more and about 120 μm or less.

[0112] The thickness of the glass layer UTG' included in the display device 100E according to the fifth embodiment of the present disclosure in the third direction DR3 can be thicker than the thickness of the glass layer UTG included in the display device 100A according to the first embodiment of the present disclosure in the third direction DR3. Therefore, the glass layer UTG' included in the display device 100E can more effectively protect the display device 100E from external impacts.

[0113] As described above, although the glass layer UTG' in the display device 100E can be relatively thick, the total thickness of the display device 100E can still be thinner than the total thickness of the display device 100A. That is, the display device 100E according to the fifth embodiment of the present disclosure can ensure a sufficient thickness of the glass layer UTG' while keeping the total thickness at a relatively low level.

[0114] In the above display device 100E according to the fifth embodiment of the present disclosure, the polyolefin resin POR' can fill a plurality of opening patterns OP' defined in the plate PLT'. The polyolefin resin POR' can improve the reliability of the plate PLT' in the foldable region FA. Specifically, if the polyolefin resin POR' is omitted, repeated shape deformation in the foldable region FA may cause the plate PLT' to sag in the direction opposite to the third direction DR3 in the foldable region FA. Therefore, the display module DM' may also sag in the foldable region FA, thereby causing a problem that creases may be generated in the display device 100E. In the present disclosure, since the polyolefin resin POR' is provided to fill the plurality of opening patterns OP', the sag of the plate PLT' in the foldable region FA can be minimized.

[0115] In an embodiment, the melting point of the polyolefin resin POR' may be about 100 °C or higher to about 180 °C or lower, preferably, about 130 °C or higher to about 150 °C or lower. When the melting point of the polyolefin resin POR' is within the above temperature range, even if the temperature of the display device 100E increases due to the operation of the display device 100E, the reliability of the polyolefin resin POR' can be maintained. In addition, the temperature required in the process of forming the polyolefin resin POR', which will be described later, can be relatively low, and thus the manufacturing efficiency can be improved.

[0116] In an embodiment, the polyolefin resin POR' may be a linear low density polyethylene (LLDPE) resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins. More specifically, the linear low density polyethylene (LLDPE) resin may be made of a polymer having a main chain including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins and side chains of C2 to C6 (preferably, C2 to C3), and the linear low density polyethylene (LLDPE) resin has a density of about 0.915 g / cm 3 or greater and about 0.935 g / cm 3 or less. The linear low density polyethylene (LLDPE) resin may have a density relatively lower than that of a high density polyethylene (HDPE) resin (i.e., a density of about 0.94 g / cm 3 or greater and about 0.966 g / cm 3 or less), and the linear low density polyethylene (LLDPE) resin may be more linear than a low density polyethylene (LDPE) resin (i.e., a resin made of a polymer having a crosslinked structure and / or side chains of C7 or more). Various resins previously known in the art may be used as the linear low density polyethylene (LLDPE) resin without limitation. When compared with the high density polyethylene (HDPE) resin and the low density polyethylene (LDPE) resin, the linear low density polyethylene (LLDPE) resin may provide excellent tensile strength, elongation, impact strength, moisture resistance, heat resistance, and compressive resistance. Therefore, the polyolefin resin POR' can sufficiently ensure reliability despite repeated shape deformation in the foldable region FA.

[0117] In an embodiment, the first adhesive layer PSA1' may overlap with the first non-foldable region NFA1 and the second non-foldable region NFA2. In addition, the first adhesive layer PSA1' may overlap with the foldable region FA. That is, the first adhesive layer PSA1' may completely cover the first non-foldable region NFA1, the foldable region FA, and the second non-foldable region NFA2.

[0118] The first adhesive layer PSA1' may cover a polyolefin resin POR' that fills a plurality of opening patterns OP' defined in a foldable region FA. That is, in the foldable region FA, there is no empty space between the plate PLT' and the display module DM'. Thus, despite repeated shape deformations of the display device 100E, the display module DM' can be sufficiently supported in the foldable region FA to minimize the generation of creases in the foldable region FA and the regions adjacent thereto.

[0119] Figure 8 is a cross-sectional view taken along line I-I' of a sixth embodiment of a display device as shown in Figure 1 .

[0120] Referring to Figure 8 , a display device 100F according to a sixth embodiment of the present disclosure may be substantially the same as the display device 100E according to the fifth embodiment of the present disclosure that has been described with reference to Figure 7 . Thus, a repeated description of components that are the same as those already described above may be omitted below Figure 8 as shown in

[0121] The first adhesive layer PSA1' in the display device 100F is different from the first adhesive layer PSA1' in the display device 100E. In the display device 100F, the first adhesive layer PSA1' may overlap with non-foldable regions NFA1 and NFA2 and may not overlap with the foldable region FA. Since the first adhesive layer PSA1' does not overlap with the foldable region FA, the display module DM' and the plate PLT' may be spaced apart from each other in the foldable region FA. That is, a portion of the plate PLT' that defines a plurality of opening patterns OP' in the foldable region FA may be spaced apart from an overlying portion of the display module DM'. Despite possible repeated deformations of the shape of the display device 100F in the foldable region FA or possible external impacts, portions of the display module DM' and the plate PLT' that define a plurality of opening patterns OP' may be substantially non-contact with each other. Thus, formation of concavo-convex patterns corresponding to the plurality of opening patterns OP' in the display module DM' can be prevented.

[0122] Figure 9 is a cross-sectional view taken along line I-I' of a seventh embodiment of a display device as shown in Figure 1 .

[0123] Referring to Figure 9 , a display device 100G according to a seventh embodiment of the present disclosure may be substantially the same as the display device 100F according to the sixth embodiment of the present disclosure that has been described with reference to Figure 8 . Thus, it will be omitted below Figure 9Components shown in and are the same as those described above are described repeatedly.

[0124] The display device 100G differs from the display device 100F in that the display device 100G includes a step difference compensation layer SCL'. In the display device 100G, the step difference compensation layer SCL' may be located on the panel PLT' in the foldable area FA and may cover the polyolefin resin POR' filling the plurality of opening patterns OP'.

[0125] The step difference compensation layer SCL' can compensate for the step difference in which the first adhesive layer PSA1' does not overlap the foldable area FA on the panel PLT'. If a portion of the display module DM' overlapping the step difference sags, the step difference compensation layer SCL' can support the sagged portion of the display module DM'. Therefore, a crease caused by the sag of the display module DM' in the foldable area FA can be effectively prevented.

[0126] In an embodiment, the step difference compensation layer SCL' may include a metal layer ML'. The step difference compensation layer SCL' may have a single layer structure including the metal layer ML'. For example, the metal layer ML' may include aluminum.

[0127] Figure 10 is based on Figure 1 0 is a cross-sectional view of an eighth embodiment of a display device shown in , taken along line II′.

[0128] Reference Figure 10 The display device 100H according to the eighth embodiment of the present disclosure can be used with reference to Figure 9 The display device 100G according to the seventh embodiment of the present disclosure is substantially the same as described above. Figure 9 Therefore, it will be omitted below. Figure 10 Description of components shown in as those described above.

[0129] The display device 100H is different from the display device 100G in that the step difference compensation layer SCL' in the display device 100H further includes a cover layer CVL'. In the display device 100H, the step difference compensation layer SCL' may include a metal layer ML' and a cover layer CVL' disposed on the metal layer ML'. Therefore, the step difference compensation layer SCL' may more effectively compensate for the step difference caused by the first adhesive layer PSA1' not overlapping the foldable area FA on the panel PLT'.

[0130] Figure 11 is a flowchart illustrating a method of manufacturing the display device according to any of the above-described embodiments.

[0131] Reference Figure 11, a method of manufacturing a display device may include step S10 and step S20. Step S10 fills a polyolefin resin into a plurality of opening patterns defined in a plate to overlap with a foldable region, and step S20 attaches the plate to a display module by interposing a first adhesive layer between the plate and the display module.

[0132] Figure 12 , Figure 13 and Figure 14 are cross-sectional views showing Figure 11 the heating and pressing steps shown in Figures 12 to 14 is a cross-sectional view showing Figure 11 an embodiment of step S10 shown in

[0133] Figure 12 shows step S11, during which a structure 30 including a polyolefin resin POR” and a step difference compensation layer SCL” may be placed on a plate PLT”. The plate PLT”, the polyolefin resin POR”, and the step difference compensation layer SCL” may be used to form any one of the plate PLT and the plate PLT' described with reference to Figures 3 to 10 , any one of the polyolefin resin POR and the polyolefin resin POR', and any one of the step difference compensation layer SCL and the step difference compensation layer SCL'.

[0134] The plate PLT” and the structure 30 may be disposed between a first pressing plate 10 and a second pressing plate 20. A first release film layer 11 may be attached to the surface of the first pressing plate 10 facing the plate PLT” and the structure 30, and a second release film layer 21 may be attached to the surface of the second pressing plate 20 facing the plate PLT” and the structure 30.

[0135] In addition, the structure 30 may be arranged such that the polyolefin resin POR” is adjacent to the plate PLT”, and the polyolefin resin POR” is closer to the plate PLT” than the step difference compensation layer SCL”. The size and position of the structure 30 may be set to overlap with the foldable region FA and not overlap with the non-foldable regions NFA1 and NFA2.

[0136] Figure 13 shows step S12, during which the structure 30 and the plate PLT” may be heated and pressed together using the first pressing plate 10 and the second pressing plate 20. For example, the first pressing plate 10 may move toward the second pressing plate 20. At this time, the polyolefin resin POR” may soften or melt, and the applied pressure may cause the polyolefin resin POR” to fill a plurality of opening patterns OP” defined in the plate PLT” (see Figure 12 ). The step difference compensation layer SCL” may not melt and may be disposed on the plate PLT” to cover the polyolefin resin POR” filling the plurality of opening patterns OP”.

[0137] Heating and pressing can be performed at a temperature equal to or higher than the melting point of the polyolefin resin "POR". For example, when the melting point of the polyolefin resin "POR" as described above is about 100°C or higher and about 180°C or lower, heating and pressing can be performed at a temperature equal to or higher than the melting point of the polyolefin resin "POR".

[0138] Figure 14 Step S13 is shown, during which the step difference compensation layer "SCL" can be removed. Step S13 may only be required for some of the embodiments described above. For example, when manufacturing the display devices 100A, 100B, 100E, or 100F already described with reference to Figure 3 , Figure 4 , Figure 7 or Figure 8 , the step S13 of removing the step difference compensation layer "SCL" can be performed. Alternatively, when manufacturing the display devices 100C, 100D, 100G, or 100H already described with reference to Figure 5 , Figure 6 , Figure 9 or Figure 10 , the step S13 of removing the step difference compensation layer "SCL" may not be performed.

[0139] According to the present disclosure, a display device may include a polyolefin resin filling a plurality of opening patterns defined in a plate. Thus, the supporting force exerted by the plate in the display device can be improved, and therefore, the display device can avoid or better prevent the formation of creases.

[0140] In a method of manufacturing a display device according to the present disclosure, the generation of creases can be substantially prevented.

[0141] Example embodiments have been disclosed herein, and although specific terms are used, these terms are used and interpreted in a general and descriptive sense only and not for the purpose of limitation. In some cases / examples, as will be apparent to those of ordinary skill in the art at the time of filing this application, features, characteristics, and / or elements related to a specific embodiment can be used alone or in combination with features, characteristics, and / or elements related to other embodiments. Thus, those skilled in the art will understand that various changes can be made to the forms and details disclosed herein without departing from the spirit and scope of the present disclosure set forth in the appended claims.

Claims

1. A display device, comprising a non-foldable region and a foldable region disposed between the non-foldable regions, wherein, The display device includes: a display module; a board that supports the display module below the display module, the board defining a plurality of opening patterns overlapping with the foldable region; a first adhesive layer interposed between the display module and the board; and a polyolefin resin filling the plurality of opening patterns.

2. The display device according to claim 1, wherein, The melting point of the polyolefin resin is 100 °C or higher and 180 °C or lower.

3. The display device according to claim 1, wherein, The polyolefin resin is a linear low-density polyethylene resin including repeating units derived from ethylene and repeating units derived from C3 to C8 α-olefins.

4. The display device according to claim 1, wherein, The first adhesive layer overlaps with the non-foldable region and does not overlap with the foldable region.

5. The display device according to claim 4, wherein, The display device further includes a step difference compensation layer that is located on the board in the foldable region and covers the polyolefin resin filling the plurality of opening patterns.

6. The display device according to claim 5, wherein, The step difference compensation layer includes a metal layer and a covering layer provided on the metal layer.

7. The display device according to claim 1, wherein, The display module includes: a protective film layer; a panel layer provided on the protective film layer, the panel layer including a plurality of pixels; and a second adhesive layer interposed between the protective film layer and the panel layer.

8. The display device according to claim 7, wherein, The first adhesive layer directly contacts each of the protective film layer and the board in the non-foldable region.

9. The display device according to claim 7, wherein, The thickness of the display module is 80 μm or greater and 120 μm or less.

10. The display device according to claim 1, wherein, The first adhesive layer overlaps with the non-foldable region and the foldable region.

Images