Display substrate

Abstract

A display substrate according to one embodiment includes a base material having a long length direction and a short length direction, including one surface and another surface, and including a first area and a second area; and a hole passing through the one surface and the another surface of the base material, wherein the first area is defined as a folding area, the second area is defined as an unfolding area, the hole includes a first hole formed in the first area, and the first hole includes at least three first holes having different sizes in the long length direction of the base material.

Description

[0001] This case is a divisional application, the parent application being the application filed on January 10, 2020, with application number 2020800080828 and invention title "Substrate for Display". Technical Field

[0002] The embodiments relate to a substrate for a display. Background Technology

[0003] Recently, there has been a growing demand for flexible display devices that can easily run various applications and display images on large screens when carried.

[0004] This flexible display can be folded or partially bent when carried or stored, but can be displayed as an folded display when showing images. Therefore, the image display area can be increased, and the user can easily carry it.

[0005] This flexible display device can be repeatedly folded or bent, and then the process of unfolding it again can be repeated.

[0006] Therefore, the substrate material of the display device needs to be strong and elastic, and should not crack or deform during folding and unfolding.

[0007] Meanwhile, when the substrate material of the display device is folded, each folded area can have a different curvature. Therefore, different compressive stresses are applied to each area according to the different curvatures generated in each folded area.

[0008] Specifically, tensile stress is generated on the outer surface of the fold according to the folding direction, and the tensile stress can be offset by the residual compressive stress. However, compressive stress is generated on the inner surface of the fold, and the residual compressive stress and the compressive stress work together. Therefore, the inner surface of the fold may be damaged or broken by the compressive stress.

[0009] Therefore, in areas of high compressive stress, fracture may occur in the substrate material during folding, and the curvature is limited when the substrate is bent, which may reduce the degree of folding of the substrate material (i.e., the degree of freedom in design).

[0010] Therefore, there is a need for a new display substrate with a structure that can improve the reliability and design freedom of the display substrate applied to such flexible display devices. Summary of the Invention

[0011] Technical issues

[0012] The embodiments are intended to provide a display substrate with improved reliability and design freedom.

[0013] Technical solution

[0014] A display substrate according to an embodiment includes: a substrate material having a long direction and a short direction, and including one surface and another surface, as well as a first region and a second region; and a hole through the one surface and the other surface of the substrate material, wherein the first region is defined as a folded region where the one surface is folded to face, the second region is defined as an unfolded region, and the hole includes a first hole formed in the first region, the first hole including at least three first holes with different sizes in the long direction of the substrate material.

[0015] Additionally, a display substrate according to an embodiment includes: a substrate material including one surface and another surface, a first region and a second region; and holes through the one surface and the other surface of the substrate material, wherein the first region is defined as a folded region where the one surface is folded to face, the second region is defined as an unfolded region, the holes include a plurality of first holes formed in the first region, each of the plurality of first holes including a first through hole formed in the one surface and a second through hole formed in the other surface, and the first region including a region where the distance between the centers of two adjacent first through holes in the plurality of first holes is different.

[0016] Additionally, a display substrate according to an embodiment includes: a substrate material including one surface and another surface, a first region and a second region; and holes through the one surface and the other surface of the substrate material, wherein the first region includes a folded region and an unfolded region where the one surface is folded to face, the second region includes an unfolded region, the holes include a plurality of first holes formed in the folded region of the first region, the plurality of first holes including a first through hole formed in the one surface and a second through hole formed in the other surface, and the first region includes a region where the distance between the centers of two adjacent first through holes among the plurality of first holes is different.

[0017] Beneficial effects

[0018] In the display substrate according to the embodiment, the size and proportion of the holes may vary depending on the degree of folding (i.e., the curvature) in the folded area of ​​the substrate material.

[0019] Therefore, it can effectively disperse the compressive stress that varies for each region depending on the curvature of the inner surface of the fold.

[0020] That is, by varying the size and proportion of the holes according to the curvature, the compressive stress in the part with a large compressive stress can be effectively dispersed, i.e. the magnitude of the generated compressive stress. Therefore, it can prevent the substrate material from cracking due to compressive stress.

[0021] Furthermore, by varying the size and proportion of the holes according to the curvature, the limitations imposed by the curvature can be reduced, and folding can be performed based on the desired curvature, thus increasing the design freedom of the display substrate.

[0022] Furthermore, in the display substrate according to the embodiment, the size of the hole per unit area may be different depending on the degree of folding (i.e., the curvature) in the folded area of ​​the substrate material.

[0023] Therefore, it can effectively disperse the compressive stress that varies for each region depending on the curvature of the inner surface of the fold.

[0024] That is, by making the size of each unit area of ​​the hole different according to the curvature, the compressive stress in the part with a large compressive stress can be effectively dispersed, that is, the magnitude of the compressive stress generated can be reduced. Therefore, it can prevent the substrate material from cracking due to compressive stress.

[0025] Furthermore, by varying the size of each unit area of ​​the aperture according to the curvature, the limitations imposed by the curvature can be reduced, and folding can be performed using the desired curvature radius, thus increasing the design freedom of the display substrate. Attached Figure Description

[0026] Figure 1 This is a perspective view of the display substrate according to an embodiment.

[0027] Figure 2 This is a diagram showing a side surface view of a display substrate according to a first embodiment.

[0028] Figure 3 This is a top view showing one surface of a display substrate according to the first embodiment.

[0029] Figure 4 This is a top view showing another surface of the display substrate according to the first embodiment.

[0030] Figure 5 This is a diagram showing another top view of one surface of a display substrate according to the first embodiment.

[0031] Figure 6 This is a diagram showing another top view of another surface of the display substrate according to the first embodiment.

[0032] Figures 7 to 10 This is another top view showing one surface and another surface of the display substrate according to the first embodiment.

[0033] Figure 11 This is a diagram showing a side surface view of a display substrate according to a second embodiment.

[0034] Figure 12 This is a top view showing one surface of a display substrate according to the second embodiment.

[0035] Figure 13 This is a top view showing another surface of the display substrate according to the second embodiment.

[0036] Figure 14 This is another top view showing one surface of the display substrate according to the second embodiment.

[0037] Figure 15 This is a diagram showing another top view of another surface of the display substrate according to the second embodiment.

[0038] Figures 16 to 19 This is another top view showing one surface and another surface of the display substrate according to the second embodiment.

[0039] Figure 20 This is a diagram showing a side surface view of a display substrate according to a third embodiment.

[0040] Figure 21 This is a top view showing one surface of a display substrate according to a third embodiment.

[0041] Figure 22 This is a top view showing another surface of the display substrate according to the third embodiment.

[0042] Figure 23 It shows along Figure 21 The diagram shows the cross-section of line AA′.

[0043] Figure 24 This is another top view showing one surface of a display substrate according to a third embodiment.

[0044] Figure 25 This is a diagram showing another top view of another surface of the display substrate according to the third embodiment.

[0045] Figure 26 It shows along Figure 24 The diagram shows the cross-sectional view taken from line BB′.

[0046] Figures 27 to 30 This is another top view showing one surface and another surface of the display substrate according to the third embodiment.

[0047] Figure 31 This is a diagram showing a side surface view of a display substrate according to a fourth embodiment.

[0048] Figure 32 This is a top view showing one surface of a display substrate according to the fourth embodiment.

[0049] Figure 33 This is a top view showing another surface of the display substrate according to the fourth embodiment.

[0050] Figure 34 It shows along Figure 32 The diagram shows the cross-sectional view taken by line CC′.

[0051] Figure 35 This is another top view showing one surface of a display substrate according to the fourth embodiment.

[0052] Figure 36 This is a diagram showing another top view of another surface of the display substrate according to the fourth embodiment.

[0053] Figure 37 It shows along Figure 35 The diagram shows the cross-sectional view of the line DD′.

[0054] Figures 38 to 41 This is another top view showing one surface and another surface of the display substrate according to the fourth embodiment.

[0055] Figure 42 This is a diagram used to describe an example of a display substrate applied according to an embodiment. Detailed Implementation

[0056] In the following, embodiments of the invention will be described in detail with reference to the accompanying drawings. However, the spirit and scope of the invention are not limited to the portion of the described embodiments, but can be implemented in various other forms, and one or more elements of the embodiments may be selectively combined and substituted within the spirit and scope of the invention.

[0057] Furthermore, unless otherwise explicitly defined and described, the terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains, and terms (e.g., terms defined in commonly used dictionaries) may be interpreted as having the same meaning as in the context of the prior art.

[0058] Furthermore, the terminology used in the embodiments of the present invention is for describing embodiments and is not intended to limit the invention. In this specification, unless specifically stated in the wording, the singular form may also include the plural form, and when described as “at least one (or more than one) of A(and) B and C”, it may include at least one of all combinations that can be combined with A, B and C.

[0059] Furthermore, when describing the elements of embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are used only to distinguish elements from other elements, and the terms are not limited to the substance, order, or sequence of the elements.

[0060] Additionally, when an element is described as being “connected,” “coupled,” or “bonded” to another element, it may include not only that the element is directly connected, coupled, or bonded to other elements, but also that the element is “connected,” “coupled,” or “bonded” through yet another element between that element and another element.

[0061] Furthermore, when described as being formed or arranged “above” or “below” in each element, “above” or “below” can include not only cases where two elements are in direct contact with each other, but also cases where one or more other elements are formed or arranged between the two elements.

[0062] Furthermore, when expressed as "above" or "below", based on a single element, it can include not only the meaning of upward direction but also the meaning of downward direction.

[0063] In the following description, a display substrate according to a first embodiment will be described with reference to the accompanying drawings.

[0064] Reference Figures 1 to 8 The display substrate according to the first embodiment includes a substrate material 100.

[0065] The substrate material 100 may include metals, metal alloys, plastics, composite materials (e.g., carbon fiber reinforced plastics, magnetic or conductive materials, glass fiber reinforced materials, etc.), ceramics, sapphire, glass, etc.

[0066] As mentioned above, when the base material 100 is rigid, bending it in one direction may generate tensile or compressive stress due to bending, which may cause damage when the base material 100 is folded or bent.

[0067] In addition, the tensile or compressive stress generated when the substrate material 100 is bent in one direction limits the curvature of the folded area, which may result in a reduction in the design freedom of the substrate material.

[0068] The display substrate according to the embodiment can prevent the substrate material from being damaged by such folding or bending, and can increase design freedom by relaxing the constraints based on curvature.

[0069] Reference Figure 1 The base material 100 can be bent in one direction.

[0070] Specifically, the substrate material 100 may include a surface 1S and another surface 2S opposite to the surface 1S. In the substrate material 100, one surface 1S or the other surface 2S may be bent to face each other.

[0071] In the following description, such as Figure 1 As shown, the substrate material 100 is bent in a direction in which one surface 1S faces each other.

[0072] In the substrate material 100, a first region 1A and a second region 2A can be defined. The first region 1A and the second region 2A can be regions defined when the substrate material 100 is bent in a direction in which one surface 1S faces each other.

[0073] Specifically, the substrate material 100 is bent in one direction, and the substrate material 100 can be divided into a first region 1A and a second region 2A, the first region 1A being the folded region (folded region) and the second region 2A being the unfolded region (unfolded region).

[0074] Specifically, refer to Figures 3 to 10 The substrate material 100 may include a first region 1A, which is a curved region of the substrate material 100. The substrate material 100 may include a second region 2A, which is not curved and is configured to be adjacent to the first region 1A.

[0075] For example, the second region 2A can be formed on the left and right sides of the first region 1A with respect to the bending direction of the substrate material 100.

[0076] The first region 1A and the second region 2A can be formed on the same substrate material 100. That is, the first region 1A and the second region 2A are not separated on the same substrate material 100 and can be formed as a whole.

[0077] The dimensions of the first region 1A and the second region 2A can be different from each other. Specifically, the dimensions of the second region 2A can be larger than the dimensions of the first region 1A.

[0078] The accompanying drawings show a first region 1A located in the center of the substrate material 100, but the embodiment is not limited thereto. That is, the first region 1A may be located at one end and end region of the substrate material 100. Specifically, the first region 1A may be located at one end and end region of the substrate material 100, such that the second region 2A is asymmetrical in size.

[0079] Holes can be formed in the first region 1A. Specifically, the first region 1A can be formed with a plurality of first holes H1 spaced apart from each other. The first holes H1 can be formed to penetrate the substrate material 100. Specifically, the first holes H1 can be formed to penetrate one surface 1S and another surface 2S of the substrate material 100.

[0080] That is, the first hole H1 can be formed to pass through a surface 1S located inside the folding direction and another surface 2S located outside the folding direction.

[0081] The first hole H1 can be formed in a regular pattern in the first region 1A. Alternatively, the first hole H1 can be formed in an irregular pattern in the first region 1A.

[0082] The first hole H1 can be formed with a curved surface. In detail, the first hole H1 can be formed with a curved surface (e.g., elliptical, hemispherical, circular, etc.).

[0083] However, the embodiments are not limited to this, and the first hole H1 can be formed in a polygonal shape, such as a triangle, a quadrilateral, etc.

[0084] Figure 2 This is a diagram showing a side surface view of a display substrate according to a first embodiment.

[0085] Reference Figure 2 The substrate 100 can be folded in one direction. More specifically, a surface 1S can be folded in a direction where they face each other.

[0086] A first region 1A and a second region 2A can be formed in the base material 100 by folding it in one direction. That is, the base material 100 can be formed with a folded region formed by folding the base material 100 in one direction and unfolded regions located at both ends of the folded region.

[0087] The folded region can be defined as the region that forms curvature R, and the unfolded region can be defined as the region that does not form curvature R or whose curvature is close to 0.

[0088] Reference Figure 2 The base material 100 is folded in one direction and can be formed in the order of unfolded area, folded area, unfolded area.

[0089] According to the embodiments, the display substrate can improve its reliability and design freedom by changing the size and proportion of the holes formed in the folded area.

[0090] Figure 3 and Figure 4 This is a diagram showing one surface and another surface of a display substrate according to a first embodiment. That is, Figure 3This is a top view showing the folded inner surface when the base material is folded 100°. Figure 4 This is a top view showing the folded outer surface when the base material is folded 100.

[0091] Reference Figure 3 A first region 1A and a second region 2A can be formed in the substrate material 100. That is, the substrate material 100 can be formed with a folded region formed by folding the substrate material 100 in one direction and unfolded regions located at both ends of the folded region. In other words, the first region 1A can be a folded region and the second region 2A can be an unfolded region.

[0092] The substrate material 100 may have a length in the long direction and a length in the short direction.

[0093] The second region 2A may extend from the first region 1A, and the second region 2A may be located on the periphery of the substrate material 100 based on the length in the longitudinal direction of the substrate material 100.

[0094] The folded region can be defined as the region that forms curvature R, and the unfolded region can be defined as the region that does not form curvature R or whose curvature is close to 0.

[0095] The folded area can be defined as the area between the first hinge HN1 and the second hinge HN2.

[0096] Specifically, the hinge portion can be defined as the point where the folding of the base material 100 begins. That is, folding begins at the first hinge portion HN1 and the second hinge portion HN2, and the base material 100 can be folded in the direction facing one surface 1S of the base material 100.

[0097] The first hinge portion HN1 and the second hinge portion HN2 may be located in the end regions of the base material 100. More specifically, the first hinge portion HN1 and the second hinge portion HN2 may be located at two end regions in the short direction of the end regions of the base material 100.

[0098] Additionally, a first hinge portion HN1 and a second hinge portion HN2 can be formed by passing through two end regions in the short direction of the base material 100. That is, the first hinge portion HN1 and the second hinge portion HN2 can be defined as holes h formed by passing through two end regions in the short direction of the base material 100.

[0099] That is, the first hinge portion HN1 and the second hinge portion HN2 are formed between the first region 1A and the second region 2A, and can be defined as a hole formed by opening the end region of the substrate material 100 in the short direction.

[0100] The shape of the hole h can be the same as or different from the shape of the first hole H1. For example, the hole h can be formed to have a curved surface. In detail, the hole h can be formed to have a curved surface (e.g., elliptical, hemispherical, circular, etc.).

[0101] However, the embodiments are not limited to this, and the hole h can be formed in a polygonal shape, such as a triangle, a quadrilateral, etc.

[0102] Reference Figure 3 The first hole H1 can be formed in the first region 1A (i.e., the folded region) between the first hinge portion HN1 and the second hinge portion HN2.

[0103] The first hole H1 may include multiple holes of different sizes in the folded region. More specifically, the first hole H1 may include at least three or more holes of different sizes in the longitudinal direction of the substrate material in the folded region.

[0104] exist Figure 3 The accompanying drawings show three types of holes with different sizes; however, the embodiments are not limited to these and may include fewer or more than three types of holes depending on the variation in curvature.

[0105] For example, the first hole H1 may include a first through hole H1-1, a second through hole H1-2, and a third through hole H1-3 disposed in the folded area. The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 may be formed in different sizes.

[0106] Specifically, the first region 1A of the substrate material 100 may include regions with different curvature magnitudes. Here, curvature magnitude refers to the degree of bending of the substrate material. That is, the curvature magnitude can increase as the substrate material bends more.

[0107] Specifically, the first region of the substrate material may include a first folded region 1-1A with a first curvature R1, a second folded region 1-2A with a second curvature R2, and a third folded region 1-3A with a third curvature R3.

[0108] The first curvature R1, the second curvature R2, and the third curvature R3 can have a size of about 1 μm to about 2 μm.

[0109] The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in the first folding region 1-1A, the second folding region 1-2A, and the third folding region 1-3A, respectively.

[0110] In this case, the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in different proportions. Here, the size of the hole can be defined as the diameter or area of ​​the hole.

[0111] That is, when the hole is formed as a circle, the size of the hole can be defined as the size of the outer diameter of the hole, that is, the maximum diameter in the long direction of one surface or the other surface on which the hole is formed.

[0112] Alternatively, when the hole is formed in a shape other than a circle, the size of the hole is defined as the size of the outer diameter of the hole, that is, the area of ​​the hole measured on one or the other surface in which the hole is formed.

[0113] The following text will primarily describe the case where the hole is formed as a circle.

[0114] Specifically, the dimensions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can vary according to the curvature of the first folded region 1-1A, the second folded region 1-2A, and the third folded region 1-3A.

[0115] Specifically, the dimensions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be proportional to the curvature. That is, in regions with high curvature, the size of the first hole can be large, and in regions with low curvature, the size of the first hole can be small.

[0116] Therefore, when the substrate material is in a folded state, the display substrate according to the first embodiment minimizes the distribution of compressive stress that varies according to the curvature, thereby achieving improved folding reliability of the display substrate.

[0117] That is, the size of the hole that can disperse compressive stress in a region with large curvature is formed to be larger than the size of the hole that can disperse compressive stress in a region with small curvature, thereby dispersing compressive stress more effectively.

[0118] Meanwhile, the difference in the maximum diameter of the first hole H1 can satisfy the following equation 1.

[0119] [Equation 1]

[0120] 0.8t ≤ the difference in maximum diameter of the first hole H1 ≤ 1.1t

[0121] (Where t is the thickness of the substrate material)

[0122] That is, the dimensions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be 0.8 to 1.1 times the thickness of the substrate material.

[0123] Meanwhile, the thickness t of the substrate material 100 can be from about 0.01 mm to about 2 mm. When the thickness of the substrate material 100 is less than about 0.01 mm, it is easy to fold or bend the substrate material 100, but this reduces the rigidity of the substrate material 100, and therefore it may be easily damaged by external impacts. When the thickness of the substrate material 100 exceeds about 2 mm, when the substrate material 100 is folded or bent, a large stress is generated due to the thickness of the substrate material 100, so the substrate material may be damaged, or the bending magnitude (i.e., the curvature of the substrate material) may be limited.

[0124] When the difference in the maximum diameter of the first hole H1 is less than 0.8 times the thickness of the substrate material, the compressive stress, depending on the curvature, may not be effectively dispersed, thus reducing reliability. When the difference in the maximum diameter of the first hole H1 is greater than 1.1 times the thickness of the substrate material, the strength of the substrate material 100 may decrease.

[0125] In addition, the difference between the maximum and minimum values ​​of the first hole H1 can satisfy the following equation 2.

[0126] [Equation 2]

[0127] 0.2t ≤ the difference between the maximum and minimum values ​​of the first hole H1

[0128] (Where t is the thickness of the substrate material)

[0129] When the difference between the maximum and minimum values ​​of the first hole H1 is less than 0.2 times the thickness of the substrate material, the compressive stress according to the curvature may not be effectively dispersed, thus reducing reliability.

[0130] Figure 4 This is a top view showing another surface of the display substrate 100. That is, it is a top view showing the exterior in the folding direction, not an interior top view.

[0131] Reference Figure 4 Since the first hole H1 is formed to pass through one surface and another surface of the base material 100, the first hole H1 formed on the other surface of the base material 100 can also be formed in the first region between the first hinge portion HN1 and the second hinge portion HN2, i.e. the folded region, similar to the position of the first hole H1 formed on one surface.

[0132] The size of the first hole H1 formed in another surface can be the same as that of the first hole formed on one surface.

[0133] That is, the other surface is the folded outer surface of the substrate material, and unlike the inner surface, it does not generate compressive stress. Therefore, the size of the first hole formed on the other surface does not vary with the magnitude of curvature and can be formed to be the same.

[0134] However, the embodiments are not limited to this, and the size of the first hole on another surface of the substrate material can be formed differently depending on the curvature, similar to the first surface described above. Alternatively, instead of forming the first hole on the other surface of the substrate material, a groove can be formed on that other surface, corresponding to the shape and size of the first hole.

[0135] Furthermore, in the first hole H1, the outer diameter formed on one surface and the outer diameter formed on another surface can be different from each other.

[0136] For example, in the first hole H1, the outer diameter formed on another surface can be smaller than the outer diameter formed on one surface. Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the outer diameter formed on the inner folded surface is larger than the outer diameter formed on the outer folded surface, thus the substrate material 100 can be easily folded.

[0137] That is, on the other surface, due to the small size of the first hole, the surface stress of the remaining substrate material increases, thus the other surface of the substrate material exhibits large expansion characteristics. Conversely, on one surface, due to the large size of the first hole, the surface stress of the remaining substrate material is relatively small, thus the one surface of the substrate material exhibits large contraction characteristics.

[0138] Therefore, when the base material 100 is folded in a direction where one surface faces the other, the base material 100 can be easily folded by making the size of the first hole on one surface relatively large.

[0139] Meanwhile, in the display substrate according to the first embodiment, what can be changed is not the size of the first hole in the folded area, but the proportion of the first hole.

[0140] Reference Figure 14 and Figure 15 The first hole H1 can be formed in the first region (i.e. the folding region FA) between the first hinge portion HN1 and the second hinge portion HN2.

[0141] The first hole H1 can be formed in different proportions in each folded region. Specifically, the folded region can include at least three regions with different proportions of the first hole in the long direction of the substrate material.

[0142] exist Figure 5 The accompanying drawings show three types of holes with different proportions; however, the embodiments are not limited to this and may include fewer or more than three types of holes depending on the size of the curvature.

[0143] Here, the proportion of the first hole can be defined as the area of ​​the first hole formed per unit area, and the proportion of the first hole can increase as the area of ​​the first hole formed increases. That is, a large proportion of the first hole can also be defined as "a large number of first holes" or "a large size of the first hole".

[0144] For example, the first hole H1 may include a first through hole H1-1, a second through hole H1-2, and a third through hole H1-3 disposed in the folded area. The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 may be formed in different proportions.

[0145] Specifically, the first region of the substrate material 100 may include regions with different curvatures. More specifically, the first region of the substrate material may include a first folded region 1-1A with a first curvature R1, a second folded region 1-2A with a second curvature R2, and a third folded region 1-3A with a third curvature R3.

[0146] The first curvature R1, the second curvature R2, and the third curvature R3 can have dimensions ranging from about 1 μm to about 2 μm.

[0147] The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in the first folding region 1-1A, the second folding region 1-2A, and the third folding region 1-3A, respectively.

[0148] In this case, the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in different proportions. Specifically, the proportions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can vary depending on the curvature of the first folded region 1-1A, the second folded region 1-2A, and the third folded region 1-3A.

[0149] Specifically, the proportions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be proportional to the magnitude of the curvature. That is, in regions with high curvature, the proportion of the first hole may be large, and in regions with low curvature, the proportion of the first hole may be small.

[0150] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0151] That is, the proportion of holes that can disperse compressive stress in regions with large curvature is greater than the proportion of holes that can disperse compressive stress in regions with small curvature, thereby dispersing compressive stress more effectively.

[0152] Figure 6This is a top view showing another surface of the base material 100. That is, it is a top view showing the exterior of the folding direction, rather than a top view showing the interior of the folding direction.

[0153] Reference Figure 6 Since the first hole H1 is formed to pass through one surface and another surface of the base material 100, the first hole H1 formed on the other surface of the base material 100 can also be formed in the first region 1A (i.e., the folded region) between the first hinge portion HN1 and the second hinge portion HN2, similar to the position of the first hole H1 formed on one surface.

[0154] The size of the first hole H1 formed on another surface can be formed in the same proportion as the first hole formed on one surface.

[0155] Therefore, a first hole formed on one surface can be partially formed to pass through another surface, and partially formed to pass through only one surface. For example, Figure 5 H1-3′, which corresponds to H1-3, can be formed as a hole through H1-3, and H1-3″ can be formed as a groove on the other surface of the display substrate.

[0156] That is, the other surface is the folded outer surface of the substrate material, and unlike the inner surface, it does not generate compressive stress. Therefore, the proportion of the first hole formed on the other surface does not vary with the magnitude of curvature and can be formed to be the same.

[0157] However, the embodiments are not limited to this, and the proportion of the first hole on another surface of the substrate material can be formed differently depending on the curvature, similar to the first surface described above. Alternatively, the first hole may not be formed on the other surface of the substrate material, but rather a groove may be formed only on that other surface, corresponding to the shape and size of the first hole.

[0158] Furthermore, in the first hole H1, the proportion of the first hole formed on one surface and the proportion of the first hole formed on the other surface can be different from each other.

[0159] For example, in the first hole H1, the proportion of the first hole formed on another surface can be less than the proportion of the first hole formed on one surface. Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the proportion of the first hole formed on the inner surface of the fold is greater than the proportion of the first hole formed on the outer surface of the fold, thus the substrate material 100 can be folded easily.

[0160] That is, on the other surface, because the proportion of the first hole is small, the surface stress of the remaining substrate material increases, thus the other surface of the substrate material has large expansion characteristics. On the other hand, on one surface, because the proportion of the first hole is large, the surface stress of the remaining substrate material is relatively small, thus the one surface of the substrate material has large contraction characteristics.

[0161] Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the substrate material 100 can be easily folded by making the proportion of the first hole on one surface relatively large.

[0162] Meanwhile, holes may also be formed in the unfolded area of ​​the display substrate according to the first embodiment.

[0163] Reference Figures 7 to 10 In the display substrate, holes can be formed in the second region of the substrate material 100.

[0164] Specifically, the substrate material 100 may include a first region 1A and a second region 2A, and a first hole H1 may be formed in the first region 1A and a second hole H2 may be formed in the second region 2A.

[0165] Since the first hole H1 formed in the first region 1A is the same as in the above embodiment, its description is omitted below. That is, referring to... Figures 3 to 6 The first hole in the above embodiment can be connected to, for example... Figures 7 to 10 The following other embodiments are combined.

[0166] Multiple second holes H2, spaced apart from each other, can be formed in the second region 2A.

[0167] The second hole H2 may overlap with one surface and the other surface of the second region 2A of the substrate material 100, to be formed to pass through the substrate material 100, or to be formed to pass through only one surface.

[0168] The size of the second hole H2 can be different from the size of the first hole H1. Alternatively, the proportion of the second hole H2 can be different from the proportion of the first hole H1.

[0169] Specifically, refer to Figure 7 and Figure 8 The size of the second hole H2 can be different from the size of the first hole H1. Specifically, the size of the second hole H2 can be smaller than the size of one of several first holes with different sizes. Alternatively, refer to... Figure 9 and Figure 10 The proportion of the second hole H2 can be different from that of the first hole H1. Specifically, the proportion of the second hole H2 can be less than the proportion of a single region among multiple regions with different proportions.

[0170] Therefore, by making the size or proportion of the holes in the second region smaller than the size or proportion of the holes in the first region, it is possible to prevent the second region from bending together when the base material is folded.

[0171] That is, according to Figures 7 to 10 In the display substrate, holes or grooves can be formed not only in curved areas but also in non-curved areas.

[0172] That is, holes or grooves can be formed in all areas of the substrate material.

[0173] Therefore, by reducing the difference between the deformation of the first region due to heat and the deformation of the second region due to heat, it is possible to prevent the display substrate from warping or twisting.

[0174] Specifically, when the difference in deformation between the first and second regions due to heat is too large, the display substrate may warp or twist. Consequently, fragmentation may occur in the substrate material in the boundary region between the first and second regions.

[0175] Therefore, in the display substrate according to the embodiment, by also forming a hole in the second region, damage to the display substrate due to thermal deformation can be prevented.

[0176] In the following text, reference will be made to Figures 11 to 19 A display substrate according to a second embodiment is described.

[0177] Reference Figure 11 The base material 100 can be folded in one direction. More specifically, a surface 1S can be folded in a direction facing each other.

[0178] By folding the substrate material 100 in one direction, a first region 1A and a second region 2A can be formed on the substrate material 100. That is, the substrate material 100 can be formed with a first region formed by folding the substrate material 100 in one direction and a second region located at both ends of the first region.

[0179] The first region can be a folded region FA and an unfolded region UFA. Furthermore, the second region can be an unfolded region UFA.

[0180] That is, the display substrate according to the second embodiment may have two folding axes, and the first region may include both the folding region FA and the unfolding region UFA.

[0181] The folded region can be defined as the region that forms curvature R, and the unfolded region can be defined as the region that does not form curvature R or whose curvature is close to 0.

[0182] That is, the size of the folded area of ​​the display substrate according to the second embodiment can be smaller than the size of the folded area of ​​the display substrate according to the first embodiment described above.

[0183] That is, refer to Figure 11 The base material 100 is folded in one direction and can be formed in the order of unfolded region, folded region, unfolded region, folded region and unfolded region.

[0184] That is, by controlling the size or proportion of the first hole, the design of the display substrate can be freely modified.

[0185] Figure 12 and Figure 13 This is a top view showing one surface and another surface of the display substrate according to the second embodiment. That is, Figure 12 This is a top view showing the folded inner surface when the base material 100 is folded. Figure 13 This is a top view showing the folded outer surface when the base material 100 is folded.

[0186] Reference Figure 12 The substrate material 100 can be formed with a first region 1A and a second region 2A.

[0187] The first region 1A may include a folded region FA and an unfolded region UFA. The folded region FA may be defined as a region that forms a curvature R, and the unfolded region UFA may be defined as a region that does not form a curvature R or has a curvature close to 0.

[0188] The folded area of ​​the first region 1A can be defined as the area between the first hinge HN1 and the second hinge HN2, and the area between the third hinge HN3 and the fourth hinge HN4. Furthermore, the unfolded area of ​​the first region 1A can be defined as the area between the second hinge HN2 and the third hinge HN3.

[0189] Specifically, the hinge portion can be defined as the point where the folding of the base material 100 begins. That is, folding begins at the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4, and the base material 100 can be folded in a direction in which one surface 1S of the base material 100 faces each other.

[0190] The first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 may be located in the end regions of the base material 100. More specifically, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 may be located at two end regions in the shorter direction of the end regions of the base material 100.

[0191] Furthermore, a first hinge portion HN1, a second hinge portion HN2, a third hinge portion HN3, and a fourth hinge portion HN4 can be formed by passing through two end regions in the shorter direction of the end regions of the base material 100. That is, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 can be defined as holes h formed by passing through two end regions in the shorter direction of the end regions of the base material 100.

[0192] That is, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3 and the fourth hinge portion HN4 are formed between the unfolded regions of the first region 1A and the second region 2A, and can be defined as holes formed by opening the end regions of the base material 100.

[0193] The shape of the hole h can be the same as or different from the shape of the first hole H1. For example, the hole h can be formed to have a curved surface. In more detail, the hole h can be formed to have a curved surface (e.g., elliptical, hemispherical, or circular shape).

[0194] However, the embodiments are not limited to this, and the hole h can be formed in a polygonal shape, such as a triangle, a quadrilateral, etc.

[0195] Reference Figure 12 The first hole H1 can be formed in the first region 1A between the first hinge portion HN1 and the second hinge portion HN2 and the first region 1A between the third hinge portion HN3 and the fourth hinge portion HN4, i.e., in the folding region.

[0196] The first hole H1 may include multiple holes of different sizes in the folded region. More specifically, the first hole H1 may include at least three or more holes of different sizes in the longitudinal direction of the substrate material in the folded region.

[0197] exist Figure 12 The accompanying drawings show three types of holes with different sizes; however, the embodiments are not limited to these and may include fewer or more than three types of holes with different sizes depending on the curvature.

[0198] For example, the first hole H1 may include a first through hole H1-1, a second through hole H1-2, and a third through hole H1-3 disposed in the folded area. The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 may be formed in different sizes.

[0199] Specifically, the folded region FA of the first region 1A of the substrate material 100 may include regions with different curvatures. More specifically, the folded region FA of the first region 1A of the substrate material may include a first folded region 1-1A with a first curvature R1, a second folded region 1-2A with a second curvature R2, and a third folded region 1-3A with a third curvature R3.

[0200] The first curvature R1, the second curvature R2, and the third curvature R3 can have a size of about 1 μm to about 2 μm.

[0201] The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in the first folding region 1-1A, the second folding region 1-2A, and the third folding region 1-3A, respectively.

[0202] In this case, the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed with different sizes. Specifically, the sizes of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can vary depending on the curvature of the first folded region 1-1A, the second folded region 1-2A, and the third folded region 1-3A.

[0203] Here, the size of the hole can be defined as its diameter or area.

[0204] That is, when the hole is formed as a circle, the size of the hole can be defined as the size of the outer diameter of the hole, that is, the maximum diameter in the long direction of one surface or the other surface on which the hole is formed.

[0205] Alternatively, when the hole is formed in a shape other than a circle, the size of the hole is defined as the size of the outer diameter of the hole, that is, the area of ​​the hole measured on one or the other surface in which the hole is formed.

[0206] The following text will primarily describe the case where the hole is formed as a circle.

[0207] Specifically, the dimensions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be proportional to the curvature. That is, in regions with high curvature, the size of the first hole can be large, and in regions with low curvature, the size of the first hole can be small.

[0208] Therefore, when the substrate material is in a folded state, the display substrate according to the second embodiment minimizes the distribution of compressive stress that varies according to the curvature, thereby achieving improved folding reliability of the display substrate.

[0209] Meanwhile, the difference in the maximum diameter of the first hole H1 can satisfy the following equation 1.

[0210] [Equation 1]

[0211] 0.8t ≤ the difference in maximum diameter of the first hole H1 ≤ 1.1t

[0212] (Where t is the thickness of the substrate material)

[0213] That is, the dimensions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be 0.8 to 1.1 times the thickness of the substrate material.

[0214] Meanwhile, the thickness t of the substrate material 100 can be from about 0.01 mm to about 2 mm. When the thickness of the substrate material 100 is less than about 0.01 mm, it is easy to fold or bend the substrate material 100, but this reduces the rigidity of the substrate material 100, and therefore it may be easily damaged by external impacts. When the thickness of the substrate material 100 exceeds about 2 mm, when the substrate material 100 is folded or bent, a large stress is generated due to the thickness of the substrate material 100, so the substrate material may be damaged, or the bending magnitude (i.e., the curvature of the substrate material) may be limited.

[0215] When the difference in the maximum diameter of the first hole H1 is less than 0.8 times the thickness of the substrate material, the compressive stress, depending on the curvature, may not be effectively dispersed, thus reducing reliability. When the difference in the maximum diameter of the first hole H1 is greater than 1.1 times the thickness of the substrate material, the strength of the substrate material 100 may decrease.

[0216] In addition, the difference between the maximum and minimum values ​​of the first hole H1 can satisfy the following equation 2.

[0217] [Equation 2]

[0218] 0.2t ≤ the difference between the maximum and minimum values ​​of the first hole H1

[0219] (Where t is the thickness of the substrate material)

[0220] When the difference between the maximum and minimum values ​​of the first hole H1 is less than 0.2 times the thickness of the substrate material, the compressive stress according to the curvature may not be effectively dispersed, thus reducing reliability.

[0221] Simultaneously, a third hole H3 can be formed in the expanded region of the first region. The third hole H3 can be formed to have the same or similar dimensions as the first hole H1, but different from it. For example, the third hole H3 can be formed from a hole of uniform size that is the same as or different from the first hole H1.

[0222] Figure 13 This is a top view showing another surface of the base material 100. That is, it is a top view showing the exterior in the folding direction, not the interior.

[0223] Reference Figure 13 Since the first hole H1 is formed to pass through one surface and another surface of the base material 100, the first hole H1 formed on the other surface of the base material 100 can also be formed in the first region between the first hinge portion HN1 and the second hinge portion HN2 and the first region between the third hinge portion HN3 and the fourth hinge portion HN4, i.e. the folded region, similar to the position of the first hole H1 formed on one surface.

[0224] The size of the first hole H1 formed in the folded region of another surface can be the same as that of the first hole formed on one surface.

[0225] That is, the other surface is the folded outer surface of the substrate material, and unlike the inner surface, it does not generate compressive stress. Therefore, the size of the first hole formed on the other surface does not vary with the magnitude of curvature and can be formed to be the same.

[0226] However, the embodiments are not limited to this, and the size of the first hole on another surface of the substrate material can be formed differently depending on the curvature, similar to the first surface described above. Alternatively, instead of forming the first hole on the other surface of the substrate material, a groove can be formed on the other surface, corresponding to the shape and size of the first hole.

[0227] Furthermore, in the first hole H1, the outer diameter formed on one surface and the outer diameter formed on another surface can be different from each other.

[0228] For example, in the first hole H1, the outer diameter formed on another surface can be smaller than the outer diameter formed on one surface. Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the outer diameter formed on the inner folded surface is larger than the outer diameter formed on the outer folded surface, thus the substrate material 100 can be easily folded.

[0229] That is, on the other surface, due to the small size of the first hole, the surface stress of the remaining substrate material increases, thus the other surface of the substrate material exhibits large expansion characteristics. Conversely, on one surface, due to the large size of the first hole, the surface stress of the remaining substrate material is relatively small, thus the one surface of the substrate material exhibits large contraction characteristics.

[0230] Therefore, when the base material 100 is folded in a direction where one surface faces the other, the base material 100 can be easily folded by making the size of the first hole on one surface relatively large.

[0231] Meanwhile, in the display substrate according to the second embodiment, what can be changed is not the size of the first hole in the folded area, but the proportion of the first hole.

[0232] Reference Figure 14 and Figure 15 The first hole H1 can be formed in the first region between the first hinge portion HN1 and the second hinge portion HN2 and the first region between the third hinge portion HN3 and the fourth hinge portion HN4, i.e., in the folding region FA.

[0233] The first hole H1 can be formed in different proportions in each folded region. Specifically, the folded region can include at least three regions with different proportions of the first hole in the long direction of the substrate material.

[0234] exist Figure 14 The accompanying drawings show three types of holes with different proportions; however, the embodiments are not limited to this and may include fewer or more than three types of holes with different proportions depending on the size of the curvature.

[0235] Here, the proportion of the first hole can be defined as the area formed by the first hole, and the proportion of the first hole can increase as the area formed by the first hole increases. That is, a large proportion of the first hole can also be defined as "a large number of first holes" or "a large size of the first hole".

[0236] For example, the first hole H1 may include a first through hole H1-1, a second through hole H1-2, and a third through hole H1-3 disposed in the folded area. The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 may be formed in different proportions.

[0237] Specifically, the folded regions of the first region of the substrate material 100 may include regions with different curvatures. More specifically, the folded regions of the first region of the substrate material may include a first folded region 1-1A with a first curvature R1, a second folded region 1-2A with a second curvature R2, and a third folded region 1-3A with a third curvature R3.

[0238] The first curvature R1, the second curvature R2, and the third curvature R3 can have a size of about 1 μm to about 2 μm.

[0239] The first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in the first folding region 1-1A, the second folding region 1-2A, and the third folding region 1-3A, respectively.

[0240] In this case, the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be formed in different proportions. Specifically, the proportions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can vary depending on the curvature of the first folded region 1-1A, the second folded region 1-2A, and the third folded region 1-3A.

[0241] Specifically, the proportions of the first through hole H1-1, the second through hole H1-2, and the third through hole H1-3 can be proportional to the curvature. That is, in regions with high curvature, the proportion of the first hole can be large, and in regions with low curvature, the proportion of the first hole can be small.

[0242] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0243] Figure 15 This is a top view showing another surface of the display substrate 100. That is, it is a top view showing the outside of the folding direction, rather than a top view showing the inside of the folding direction.

[0244] Reference Figure 15 Since the first hole H1 is formed to pass through one surface and another surface of the base material 100, the first hole H1 formed on the other surface of the base material 100 can also be formed in the first region between the first hinge portion HN1 and the second hinge portion HN2 and the first region between the third hinge portion HN3 and the fourth hinge portion HN4, i.e. the folded region FA, similar to the position of the first hole H1 formed on one surface.

[0245] The size of the first hole H1 formed on another surface can be formed to be the same as that of the first hole formed on one surface.

[0246] Therefore, a first hole formed on one surface can be partially formed to pass through another surface, and partially formed to pass through only one surface.

[0247] That is, the other surface is the folded outer surface of the substrate material, and unlike the inner surface, it does not generate compressive stress. Therefore, the proportion of the first hole formed on the other surface does not vary with the magnitude of curvature and can be the same.

[0248] However, the embodiments are not limited to this, and the proportion of the first hole on another surface of the substrate material can be formed differently depending on the curvature, similar to the first surface described above. Alternatively, instead of forming the first hole on the other surface of the substrate material, a groove can be formed on the other surface, similar in shape and size to the first hole.

[0249] Furthermore, in the first hole H1, the proportion of the first hole formed on one surface and the proportion of the first hole formed on the other surface can be different from each other.

[0250] For example, in the first hole H1, the proportion of the first hole formed on another surface can be less than the proportion of the first hole formed on one surface. Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the proportion of the first hole formed on the inner surface of the fold is greater than the proportion of the first hole formed on the outer surface of the fold, thus the substrate material 100 can be folded easily.

[0251] That is, on the other surface, because the proportion of the first hole is small, the surface stress of the remaining substrate material increases, thus the other surface of the substrate material has large expansion characteristics. On the other hand, on one surface, because the proportion of the first hole is large, the surface stress of the remaining substrate material is relatively small, thus the one surface of the substrate material has large contraction characteristics.

[0252] Therefore, when the substrate material 100 is folded in a direction where one surface faces the other, the substrate material 100 can be easily folded by making the proportion of the first hole on one surface relatively large.

[0253] Meanwhile, in the display substrate according to the second embodiment, holes can be formed in the unfolded area.

[0254] Reference Figures 16 to 19 In the display substrate, holes can be formed in the second region of the substrate material 100.

[0255] Specifically, the substrate material 100 may include a first region 1A and a second region 2A, and a first hole H1 and a third hole H3 may be formed in the first region 1A, and a second hole H2 may be formed in the second region 2A.

[0256] Since the first hole H1 and the third hole H3 formed in the first region 1A are the same as in the above embodiment, their description is omitted below. That is, referring to... Figures 12 to 15 The first and third holes of the above embodiments can be combined with the following other embodiments.

[0257] Multiple second holes H2, spaced apart from each other, can be formed in the second region 2A.

[0258] The second hole H2 may overlap with one surface and the other surface of the second region 2A of the substrate material 100, and be formed to pass through the substrate material 100.

[0259] The size of the second hole H2 can be different from the sizes of the first hole H1 and the third hole H3. Alternatively, the proportion of the second hole H2 can be different from the proportion of the first hole H1.

[0260] Specifically, refer to Figure 16 and Figure 17 The size of the second hole H2 can be different from the sizes of the first hole H1 and the third hole H3. Specifically, the size of the second hole H2 can be smaller than the size of one of a variety of first holes with different sizes or the size of the third hole H3.

[0261] Alternatively, refer to Figure 18 and Figure 19 The proportion of the second hole H2 can be different from that of the first hole H1. Specifically, the proportion of the second hole H2 can be different from the proportion of a single region among multiple regions with different proportions.

[0262] Therefore, by making the size or proportion of the holes in the second region smaller than the size or proportion of the holes in the first region, it is possible to prevent the second region from bending together when the base material is folded.

[0263] That is, according to Figures 16 to 19 In a display substrate, holes can be formed not only in the first region but also in the non-bent second region.

[0264] Therefore, by reducing the difference between the deformation of the first region due to heat and the deformation of the second region due to heat, it is possible to prevent the display substrate from warping or twisting.

[0265] Specifically, when the difference in deformation between the first and second regions due to heat is too large, the display substrate may warp or twist. Consequently, fragmentation may occur in the substrate material in the boundary region between the first and second regions.

[0266] Therefore, in the display substrate according to the embodiment, by also forming a hole in the second region, damage to the display substrate due to thermal deformation can be prevented.

[0267] In the display substrate according to the second embodiment, the size and proportion of the holes can vary depending on the degree of folding (i.e., the curvature) in the folded area of ​​the substrate material.

[0268] Therefore, it can effectively disperse the compressive stress that varies for each region depending on the curvature of the inner surface of the fold.

[0269] That is, by varying the size and proportion of the holes according to the curvature (i.e., the magnitude of the compressive stress generated), the compressive stress in the part where the compressive stress is large can be effectively dispersed, thus preventing the fragmentation of the base material due to compressive stress.

[0270] Furthermore, by varying the size and proportion of the holes according to the curvature, the limitations imposed by the curvature can be reduced, and folding can be performed based on the desired curvature, thus increasing the design freedom of the display substrate.

[0271] In the following text, reference will be made to Figures 20 to 30 A display substrate according to a third embodiment is described. In the description of the display substrate according to the third embodiment, descriptions of content that is the same as or similar to that in the above embodiments will be omitted, and the same reference numerals will be used to refer to the same elements.

[0272] Figure 20 This is a side view of the display substrate according to the third embodiment. Figure 21 and Figure 22 This is a diagram showing one surface and another surface of a display substrate according to a third embodiment. That is, Figure 21 This is a top view showing the folded inner surface when the base material is folded 100°. Figure 22 This is a top view showing the folded outer surface when the base material is folded 100.

[0273] Reference Figure 21 A first region 1A and a second region 2A can be formed in the substrate material 100. That is, the substrate material 100 can be formed with a folded region formed by folding the substrate material 100 in one direction and unfolded regions located at both ends of the folded region. In other words, the first region 1A can be a folded region and the second region 2A can be an unfolded region.

[0274] The folded region can be defined as the region that forms curvature R, and the unfolded region can be defined as the region that does not form curvature R or whose curvature is close to 0.

[0275] Furthermore, the first region 1A and the second region 2A can be divided based on whether or not a hinge portion is formed. Specifically, multiple hinge portions can be formed in the first region 1A, while no hinge portion can be formed in the second region 2A.

[0276] That is, the folded area can be defined as the area that forms the first hinge HN1 and the second hinge HN2.

[0277] Specifically, the hinge portion can be defined as the point where the folding of the base material 100 begins. That is, folding begins at the first hinge portion HN1 and the second hinge portion HN2, and the base material 100 can be folded in a direction in which one surface 1S of the base material 100 faces each other.

[0278] This hinge portion can include multiple hinge portions depending on the folding shape of the base material 100. The hinge portion can be formed at the end of the base material, and its length in the shorter direction based on the width direction of the base material 100 overlaps with the direction of the row where the first hole H1 is formed.

[0279] Specifically, the first hinge portion HN1 and the second hinge portion HN2 may be located in the end regions of the base material 100. More specifically, the first hinge portion HN1 and the second hinge portion HN2 may be located at two end regions in the shorter direction of the end regions of the base material 100.

[0280] Alternatively, the first hinge portion HN1 and the second hinge portion HN2 can be formed by passing through a region in the short direction of the end region of the base material 100. That is, the first hinge portion HN1 and the second hinge portion HN2 can be defined as holes formed by passing through two end regions in the short direction of the end region of the base material 100.

[0281] The shape of the hole in the hinge can be the same as or different from the shape of the first hole H1. For example, the hole can be formed with a curved surface. More specifically, the hole can be formed with a curved surface (e.g., elliptical, hemispherical, circular, etc.).

[0282] However, the embodiments are not limited to this, and the holes can be formed in polygonal shapes, such as triangles, quadrilaterals, etc.

[0283] Reference Figure 21 The first hole H1 can be formed in the first region 1A, i.e. the folding region, where the first hinge portion HN1 and the second hinge portion HN2 are formed.

[0284] The first hole H1 can be formed such that the size of each unit area of ​​the first hole H is different for each region in the folded region.

[0285] That is, for each region in the folded region, the size of the first hole H1 formed in the inner surface of the substrate material (i.e., a surface 1S of the substrate material) by the folded substrate material 100 can be formed to be different from each other.

[0286] Here, the size of each unit area of ​​the first hole H1 can be defined as the area forming the first hole H1 per unit area, and the increase of the size of each unit area of ​​the first hole H1 can also be defined as the increase of the size of the first hole or the increase of the number of the first holes.

[0287] At least two folded regions can be defined in the substrate material 100. For example, at least two folded regions can be defined in the substrate material 100 according to the curvature of the substrate material 100 formed by folding the substrate material 100.

[0288] Reference Figure 21 The first region 1A of the substrate material 100 may include a first curvature region RA1 and a second curvature region RA2. That is, the first region 1A may include a first curvature region RA1 and a second curvature region RA2 with different sizes.

[0289] Despite Figure 21 Two curvature regions are defined in the specification; however, the implementation is not limited to this, and various numbers of curvature regions can be defined depending on the curvature magnitude.

[0290] The first curvature region RA1 and the second curvature region RA2 can have different curvature magnitudes.

[0291] Here, curvature magnitude can refer to the size of the radius of curvature that occurs when the substrate material warps. That is, when the radius of curvature is small, the curvature magnitude is large, so it can indicate a large warping of the substrate material, and when the radius of curvature is large, the curvature magnitude is small, so it can indicate a relatively small warping of the substrate material.

[0292] Specifically, the radius of curvature of the first curvature region RA1, which is closer to the folding axis, is smaller than the radius of curvature of the second curvature region RA2, which is farther away from the folding axis than the first curvature region RA1.

[0293] The size per unit area of ​​the first hole H1 formed in the first curvature region RA1 and the second curvature region RA2 can be different from each other. In detail, the size per unit area of ​​the first hole H1 formed in the first curvature region RA1 can be larger than the size per unit area of ​​the first hole H1 formed in the second curvature region RA2.

[0294] That is, the first hole H1 formed in the first region 1A can be formed such that the hole size per unit area in the region with a smaller radius of curvature is further increased.

[0295] In other words, the distance d1 between the first holes H1 formed in the first curvature region RA1 can be smaller than the distance d2 between the first holes H1 formed in the second curvature region RA2. That is, the first holes H1 formed in the first curvature region RA1 can be formed more densely, i.e., have a higher density than the first holes H1 formed in the second curvature region RA2.

[0296] Figure 23 It is along Figure 21 The cross-sectional view taken by line AA′ is a diagram showing the shape of the first hole passing through one surface 1S and another surface 2S.

[0297] Reference Figure 23 The first hole H1 may include a first through hole h1 passing through one surface 1S and a second through hole h2 passing through another surface 2S.

[0298] The first through hole h1 and the second through hole h2 can have an inner diameter IR and an outer diameter OR. That is, the outer diameter of the first through hole h1 and the second through hole h2 can be larger than the inner diameter.

[0299] The outer diameter of the first through hole h1 and the second through hole h2 can be from about 0.01 mm to about 10 mm.

[0300] In the first through hole h1 and the second through hole h2, a central axis passing through the center of each through hole can be defined. That is, a central axis passing through the center of the outer diameter of the first through hole h1 and the outer diameter of the second through hole h2 can be defined.

[0301] In the first curvature region RA1, the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 in a first hole can be different. Conversely, in the second curvature region RA2, the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 in a first hole can be the same.

[0302] That is, the position of the first central axis C1 of the first through hole h1 in the first curvature region RA1 can be closer to the folding axis than the second central axis C2 of the second through hole h2 in the second curvature region RA2. In other words, in the first curvature region RA1, the first central axis C1 of the first through hole h1 can be offset to be closer to the folding axis than the second central axis C2 of the second through hole h2.

[0303] In other words, the first region may include areas where the distance between the centers of two adjacent first holes is different.

[0304] That is, the distance between the first central axis C1 of adjacent first through holes h1 in the first curvature region RA1 can be less than the distance between the first central axis C1 of adjacent first through holes h1 in the second curvature region RA2.

[0305] That is, in the first curvature region RA1, the position of the first through hole h1 can be changed such that as the position moves closer to the folding axis, the area of ​​the first through hole h1 per unit area increases.

[0306] That is, the position of the first central axis C1 of the first through hole can be offset relative to the second central axis C2 of the second through hole in the folding axis direction.

[0307] That is, the first through hole can be formed to be offset in the folding axis direction to be separated from the dummy through hole by a predetermined distance relative to the dummy through hole shown by the dashed line.

[0308] In addition, the position of the first central axis C1 of the first through hole can be offset more and more toward the folding axis.

[0309] That is, the distance between the first central axis C1 of adjacent first through holes h1 in the first curvature region RA1 can gradually decrease toward the folding axis.

[0310] In this case, the offset distance d3 of the central axis of the first through hole h1 can satisfy the following equation 3:

[0311] [Equation 3]

[0312] 0.1t ≤ offset distance d3 of the center axis of the first through hole ≤ 10t

[0313] (Where t is the thickness of the substrate material)

[0314] Therefore, the first hole formed on the folded inner surface (i.e., one surface 1S of the substrate material) can have different dimensions per unit area in regions with different radii of curvature. Thus, in regions with small radii of curvature, the dimension per unit area of ​​the first hole can be formed to be larger, and in regions with large radii of curvature, the dimension per unit area of ​​the first hole can be formed to be relatively smaller.

[0315] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0316] That is, the proportion of holes that can disperse compressive stress in regions with small radii of curvature is formed to be greater than the proportion of holes in regions with large radii of curvature, thereby more effectively dispersing the compressive stress generated on the folded inner surface of the substrate material.

[0317] Figure 22 This is a top view showing another surface of the base material 100. That is, it is a top view showing the exterior in the folding direction, not the interior.

[0318] Reference Figure 22 and Figure 23 In another surface 2S (which is a folded outer surface), the first hole H1 can be formed to have the same size per unit area in the first curvature region RA1 and the second curvature region RA2.

[0319] That is, on another surface 2S, the first central axis C1 in the first curvature region RA1 and the second central axis C2 in the second curvature region RA2 can coincide with each other.

[0320] That is, on another surface, the position of the second through hole in the first curvature region RA1 can be at the same distance as the second through hole in the second curvature region RA2.

[0321] That is, like the folded outer surface of the base material, unlike the inner surface, the other surface does not generate compressive stress. Therefore, the size of the first hole formed on the other surface does not vary with the magnitude of curvature, but can be formed to have the same size.

[0322] Meanwhile, the embodiments are not limited to this, and by offsetting the position of the second through hole in the folding axis direction according to the curvature, another surface of the base material can be formed, similar to the one surface mentioned above.

[0323] Reference Figures 24 to 26 The first hole H1 can be formed in the first region 1A (i.e., the folded region) where the first hinge portion HN1 and the second hinge portion HN2 are formed.

[0324] The first hole H1 can be formed such that each unit area of ​​the folded region has a different size. Specifically, the folded region may include regions having a first hole with a different size per unit area.

[0325] That is, for each region in the folded region, the size of the first hole H1 formed in the inner surface of the substrate material (i.e., a surface 1S of the substrate material) by the folded substrate material 100 can be formed to be different from each other.

[0326] Here, the size of each unit area of ​​the first hole H1 can be defined as the area forming the first hole H1 per unit area, and the increase of the size of each unit area of ​​the first hole H1 can also be defined as the increase of the size of the first hole or the increase of the number of the first holes.

[0327] At least two folded regions can be defined in the substrate material 100. For example, at least two folded regions can be defined in the substrate material 100 based on the curvature of the substrate material 100 formed by folding the substrate material 100.

[0328] Reference Figure 24 and Figure 26 The first region 1A of the substrate material 100 may include a first curvature region RA1 and a second curvature region RA2. That is, the first region 1A may include a first curvature region RA1 and a second curvature region RA2 with different sizes.

[0329] Despite Figure 24 Two curvature regions are defined in the specification; however, the implementation is not limited to this, and various numbers of curvature regions can be defined depending on the curvature magnitude.

[0330] Due to reference Figures 24 to 26 The shapes of the first hole, the first through hole, and the second through hole on a surface 1S described above are similar to those described above. Figure 21 and 23 Similar or identical, descriptions omitted below.

[0331] Refer to 25 and Figure 26 The first curvature region RA1 and the second curvature region RA2 on the other surface of the substrate material 100 can have different radii of curvature. Specifically, the radius of curvature of the first curvature region RA1, which is closer to the folding axis, can be smaller than the radius of curvature of the second curvature region RA2, which is farther from the folding axis than the first curvature region RA1.

[0332] The size per unit area of ​​the first hole H1 formed in the first curvature region RA1 and the second curvature region RA2 can be different from each other. In detail, the size per unit area of ​​the first hole H1 formed in the first curvature region RA1 can be larger than the size per unit area of ​​the first hole H1 formed in the second curvature region RA2.

[0333] In other words, the distance d1 between the first holes H1 formed in the first curvature region RA1 can be smaller than the distance d2 between the first holes H1 formed in the second curvature region RA2.

[0334] That is, the first hole H1 formed in the first curvature region RA1 can be formed more densely, that is, it has a higher density than the first hole H1 formed in the second curvature region RA2.

[0335] Figure 26 It is along Figure 24 The cross-sectional view taken by line BB′ is a diagram showing the shape of the first hole passing through one surface 1S and another surface 2S.

[0336] Reference Figure 26 The first hole H1 may include a first through hole h1 passing through one surface 1S and a second through hole h2 passing through another surface 2S.

[0337] The first through hole h1 and the second through hole h2 can have an inner diameter IR and an outer diameter OR. That is, the outer diameter of the first through hole h1 and the second through hole h2 can be larger than the inner diameter.

[0338] The outer diameter of the first through hole h1 and the second through hole h2 can be from about 0.01 mm to about 10 mm.

[0339] In the first through hole h1 and the second through hole h2, a central axis passing through the center of each through hole can be defined. That is, in the first through hole h1 and the second through hole h2, a first central axis and a second central axis passing through the center of the outer diameter of each through hole can be defined.

[0340] In the first curvature region RA1, the positions of the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be close to the folding axis. That is, in the first curvature region RA1, the distance between the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be closer than the distance between the first central axis and the second central axis in the second curvature region RA2.

[0341] In other words, the first region may include regions where the distance between the centers of two adjacent first holes is different, and may also include regions where the distance between the centers of two adjacent second through holes is different.

[0342] That is, in the first curvature region RA1, the positions of the first through hole h1 and the second through hole h2 can be changed such that as the position moves closer to the folding axis, the size of the first through hole h1 per unit area increases.

[0343] That is, in the first curvature region RA1, the distance between the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be offset to be closer than the distance between the first central axis and the second central axis in the second curvature region RA2.

[0344] That is, the first through hole and the second through hole can be formed to be offset in the folding axis direction so as to be separated by a predetermined distance from the dummy through hole shown by the dashed line.

[0345] In addition, the positions of the first central axis C1 of the first through hole and / or the second central axis C2 of the second through hole can be offset more and more toward the folding axis.

[0346] That is, the distance between the first central axis C1 of adjacent first through holes h1 and / or the distance between the second central axis C2 of second through holes h2 in the first curvature region RA1 can gradually decrease toward the folding axis.

[0347] In this case, the offset distance d3 of the center axis of the first through hole h1 and the offset distance d4 of the center axis of the second through hole h2 can satisfy the following equation 4.

[0348] [Equation 4]

[0349] 0.1t ≤ offset distance d3 of the center axis of the first through hole, and offset distance d4 of the center axis of the second through hole ≤ 10t

[0350] (Where t is the thickness of the substrate material)

[0351] The offset distance d3 of the first through hole h1 and the offset distance d4 of the second through hole h2 can be the same or different. That is, in the first curvature region RA1, the first through hole and the second through hole can be formed to be offset from each other by the same distance, so that the first central axis and the second central axis coincide with each other. Alternatively, in the first curvature region RA1, the first through hole and the second through hole can be formed to be offset by different distances to change the first central axis and the second central axis.

[0352] Therefore, the size per unit area of ​​the first hole formed on the folded inner surface (i.e., one surface and another surface of the substrate material) can differ in regions with different curvatures. Thus, in regions with small radii of curvature, the size per unit area of ​​the first hole can be formed to be larger, and in regions with large radii of curvature, the size per unit area of ​​the first hole can be formed to be relatively smaller.

[0353] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0354] In addition, by making the size of the holes per unit area similar in one surface region and another surface region, stress in each curvature region can be effectively distributed during folding.

[0355] That is, the proportion of holes that can disperse compressive stress in regions with small radii of curvature is formed to be greater than the proportion of holes in regions with large radii of curvature, thereby more effectively dispersing the compressive stress generated on the folded inner surface of the substrate material.

[0356] Meanwhile, holes may also be formed in the unfolded area of ​​the display substrate according to the embodiment.

[0357] Reference Figures 27 to 30 In the display substrate, holes can be formed in the second region of the substrate material 100.

[0358] Specifically, the substrate material 100 may include a first region 1A and a second region 2A, in which a first hole H1 may be formed and a second hole H2 may be formed.

[0359] Since the first hole H1 formed in the first region 1A is the same as in the above embodiment, the following description is omitted. That is, referring to... Figures 21 to 24 The first hole in the above embodiment can be with Figures 9 to 12 Combined with the other embodiments shown below.

[0360] Multiple second holes H2, spaced apart from each other, can be formed in the second region 2A.

[0361] The second hole H2 may overlap with one surface and the other surface of the second region 2A of the substrate material 100, to be formed to pass through the substrate material 100, or to be formed to pass through only one surface.

[0362] The dimensions of the second hole H2 can be different from those of the first hole H1. Alternatively, the outer and inner diameters of the second hole H2 can be different from those of the first hole H1.

[0363] Specifically, refer to Figures 27 to 30 The size of the second hole H2 can be smaller than the size of the first hole H1.

[0364] Therefore, by making the size or proportion of the holes in the second region smaller than the size or proportion of the holes in the first region, it is possible to prevent the second region from bending together when the base material is folded.

[0365] Alternatively, refer to Figures 27 to 30 The size per unit area of ​​the second hole H2 can be smaller than the size per unit area of ​​the first hole in the first curvature region and the second curvature region of the first region.

[0366] Therefore, the size per unit area of ​​the second hole H2 is smaller than the size per unit area of ​​the first hole in the first region, so the folded region and the unfolded region can be spaced apart, and since no hinge is formed in the second region, the first region can be warped by a smaller force than the second region. That is, according to Figures 27 to 30 In the display substrate, holes can be formed not only in curved areas but also in non-curved areas.

[0367] That is, pores can be formed in all areas of the substrate material.

[0368] Therefore, by reducing the difference between the deformation of the first region due to heat and the deformation of the second region due to heat, it is possible to prevent the display substrate from warping or twisting.

[0369] Specifically, when the difference in deformation between the first and second regions due to heat is too large, the display substrate may warp or twist. Consequently, fragmentation may occur in the substrate material in the boundary region between the first and second regions.

[0370] Therefore, in the display substrate according to the embodiment, by also forming a hole in the second region, damage to the display substrate due to thermal deformation can be prevented.

[0371] In the following text, reference will be made to Figures 31 to 41 A display substrate according to a fourth embodiment is described. In the description of the display substrate according to the fourth embodiment, descriptions of content that is the same as or similar to that in the above embodiments will be omitted, and the same reference numerals may refer to the same elements.

[0372] Reference Figure 31 The base material 100 can be folded in one direction. More specifically, a surface 1S can be folded in a direction facing each other.

[0373] By folding the substrate material 100 in one direction, a first region 1A and a second region 2A can be formed on the substrate material 100. That is, the substrate material 100 can be formed with a first region formed by folding the substrate material 100 in one direction and a second region located at both ends of the first region.

[0374] The first region can be a folded region FA and an unfolded region UFA. Furthermore, the second region can be an unfolded region UFA.

[0375] That is, the display substrate according to the fourth embodiment may have two folding axes, namely a first folding axis and a second folding axis, and the first region may include both a folding region FA and an unfolding region UFA.

[0376] The folded region can be defined as the region that forms a curvature R generated by warping the substrate material, and the unfolded region can be defined as the region that does not form a curvature R or has a curvature close to 0.

[0377] That is, the size of the folded area of ​​the display substrate according to the fourth embodiment can be smaller than the size of the folded area of ​​the display substrate according to the third embodiment described above.

[0378] That is, refer to Figure 31 The base material 100 is folded in one direction and can be formed in the order of unfolded region, folded region, unfolded region, folded region and unfolded region.

[0379] That is, by controlling the proportion of the first hole, i.e. the size of the hole per unit area, the design of the display substrate can be freely modified.

[0380] Figure 32 and Figure 33 This is a diagram showing one surface and another surface of a display substrate according to a fourth embodiment. That is, Figure 32 This is a top view showing the folded inner surface when the base material 100 is folded. Figure 33 This is a top view showing the folded outer surface when the base material 100 is folded.

[0381] in addition, Figure 34 This is a cross-sectional view used to describe the shape and position of the holes in the display substrate according to the fourth embodiment.

[0382] Reference Figure 32 The substrate material 100 can be formed with a first region 1A and a second region 2A.

[0383] The first region 1A may include a folded region FA and an unfolded region UFA. The folded region FA can be defined as a region that forms curvature R, and the unfolded region UFA can be defined as a region that does not form curvature or has curvature close to 0.

[0384] The folded area of ​​the first region 1A can be defined as the area forming the first hinge portion HN1 and the second hinge portion HN2, and the area forming the third hinge portion HN3 and the fourth hinge portion HN4. Furthermore, the unfolded area of ​​the first region 1A can be defined as the area between the second hinge portion HN2 and the third hinge portion HN3.

[0385] Specifically, the hinge portion can be defined as the point where the folding of the base material 100 begins. That is, folding begins at the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the second hinge portion HN4, and the base material 100 can be folded in a direction in which one surface 1S of the base material 100 faces each other.

[0386] This hinge portion can include multiple hinge portions depending on the folding shape of the base material 100. The hinge portion can be formed at the end of the base material, and its length in the shorter direction based on the width direction of the base material 100 overlaps with the direction of the row where the first hole H1 is formed.

[0387] The first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 may be located in the end regions of the base material 100. More specifically, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 may be located at two end regions in the shorter direction of the end regions of the base material 100.

[0388] Furthermore, a first hinge portion HN1, a second hinge portion HN2, a third hinge portion HN3, and a fourth hinge portion HN4 can be formed by passing through two end regions in the shorter direction of the end regions of the base material 100. That is, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 can be defined as holes formed by passing through two end regions in the shorter direction of the end regions of the base material 100.

[0389] The shape of the hole can be the same as or different from the shape of the first hole H1. For example, the hole can be formed with a curved surface. In detail, the hole h can be formed with a curved surface (e.g., elliptical, hemispherical, or circular).

[0390] However, the embodiments are not limited to this, and the hole h can be formed in a polygonal shape, such as a triangle, a quadrilateral, etc.

[0391] Reference Figure 32 and Figure 34 The first hole H1 can be formed in the first region 1A where the first hinge portion HN1 and the second hinge portion HN2 are formed, and in the first region 1A where the third hinge portion HN3 and the fourth hinge portion HN4 are formed, i.e., in the folding region.

[0392] The first hole H1 can be formed such that the size of each unit area of ​​the first hole H1 is different for each region in the folded region.

[0393] That is, for each region in the folded region, the size of the first hole H1 formed in the inner surface of the substrate material (i.e., a surface 1S of the substrate material) by the folded substrate material 100 can be formed to be different from each other.

[0394] Here, the size of each unit area of ​​the first hole H1 can be defined as the area forming the first hole H1 per unit area, and the increase of the size of each unit area of ​​the first hole can also be defined as the increase of the size of the first hole or the increase of the number of the first holes.

[0395] Reference Figure 32 The first region 1A of the substrate material 100 may include a first curvature region RA1 and a second curvature region RA2. That is, the first region 1A may include a first curvature region RA1 and a second curvature region RA2 with different sizes.

[0396] Here, curvature magnitude can refer to the size of the radius of curvature. That is, when the radius of curvature is small, the curvature magnitude is large, so it can refer to a large warpage of the substrate material, and when the radius of curvature is large, the curvature magnitude is small, so it can refer to a relatively small warpage of the substrate material.

[0397] The first curvature region RA1 and the second curvature region RA2 can have different radii of curvature. Specifically, the radius of curvature of the first curvature region RA1, which is closer to the folding axis, can be smaller than the radius of curvature of the second curvature region RA2, which is farther from the folding axis than the first curvature region RA1.

[0398] The size per unit area of ​​the first hole H1 formed in the first curvature region RA1 and the second curvature region RA2 can be different from each other. In detail, the size per unit area of ​​the first hole H1 formed in the first curvature region RA1 can be larger than the size per unit area of ​​the first hole H1 formed in the second curvature region RA2.

[0399] That is, the first hole H1 formed in the first region 1A can be formed such that the hole size per unit area in the region with a smaller radius of curvature is further increased.

[0400] In other words, the distance d1 between the first holes H1 formed in the first curvature region RA1 can be smaller than the distance d2 between the first holes H1 formed in the second curvature region RA2.

[0401] That is, the first hole H1 formed in the first curvature region RA1 can be formed more densely, that is, it has a higher density than the first hole H1 formed in the second curvature region RA2.

[0402] Figure 34 It is along Figure 32 The cross-sectional view taken by line CC′ is a diagram showing the shape of the first hole passing through one surface 1S and another surface 2S.

[0403] Reference Figure 34 The first hole H1 may include a first through hole h1 passing through one surface 1S and a second through hole h2 passing through another surface 2S.

[0404] The first through hole h1 and the second through hole h2 can have an inner diameter IR and an outer diameter OR. That is, the outer diameter of the first through hole h1 and the second through hole h2 can be larger than the inner diameter.

[0405] The outer diameter of the first through hole h1 and the second through hole h2 can be from about 0.01 mm to about 10 mm.

[0406] In the first through hole h1 and the second through hole h2, a central axis passing through the center of each through hole can be defined. That is, a central axis passing through the center of the outer diameter of the first through hole h1 and the outer diameter of the second through hole h2 can be defined.

[0407] In the first curvature region RA1, the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 in a first hole can be different.

[0408] Additionally, in the second curvature region RA2, the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 in the first hole can be the same.

[0409] That is, the position of the first central axis C1 of the first through hole h1 in the first curvature region RA1 can be closer to the folding axis than the second central axis C2 of the second through hole h2 in the second curvature region RA2. In other words, in the first curvature region RA1, the first central axis C1 of the first through hole h1 can be offset to be closer to the folding axis than the second central axis C2 of the second through hole h2.

[0410] In other words, the first region may include areas where the distance between the centers of two adjacent first holes is different.

[0411] That is, the distance between the first central axis C1 of adjacent first through holes h1 in the first curvature region RA1 can be less than the distance between the first central axis C1 of adjacent first through holes h1 in the second curvature region RA2.

[0412] That is, in the first curvature region RA1, the position of the first through hole h1 can be changed such that as the position moves closer to the folding axis, the area of ​​the first through hole h1 per unit area increases.

[0413] That is, the position of the first central axis C1 of the first through hole can be offset relative to the second central axis C2 of the second through hole in the folding axis direction.

[0414] In addition, the position of the first central axis C1 of the first through hole can be offset more and more toward the folding axis.

[0415] That is, the distance between the first central axis C1 of adjacent first through holes h1 in the first curvature region RA1 can gradually decrease toward the folding axis.

[0416] In this case, the offset distance d3 of the central axis of the first through hole h1 can satisfy the following equation 3:

[0417] [Equation 3]

[0418] 0.1t ≤ offset distance d3 of the center axis of the first through hole ≤ 10t

[0419] (Where t is the thickness of the substrate material)

[0420] Therefore, the first hole formed on the folded inner surface (i.e., one surface 1S of the substrate material) can have different dimensions per unit area in regions with different radii of curvature. Thus, in regions with small radii of curvature, the dimension per unit area of ​​the first hole can be formed to be larger, and in regions with large radii of curvature, the dimension per unit area of ​​the first hole can be formed to be relatively smaller.

[0421] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0422] That is, the proportion of holes that can disperse compressive stress in regions with small radii of curvature is formed to be greater than the proportion of holes in regions with large radii of curvature, thereby more effectively dispersing the compressive stress generated on the folded inner surface of the substrate material.

[0423] Figure 33 This is a top view showing another surface of the base material 100. That is, it is a top view showing the exterior in the folding direction, not the interior.

[0424] Reference Figure 32 and Figure 33 In another surface 2S (which is a folded outer surface), the first hole H1 can be formed to have the same size per unit area in the first curvature region RA1 and the second curvature region RA2.

[0425] That is, on another surface 2S, the first central axis C1 in the first curvature region RA1 and the second central axis C2 in the second curvature region RA2 can coincide with each other.

[0426] That is, in another surface, the position of the second through hole in the first curvature region RA1 can be at the same distance from the second through hole in the second curvature region RA2.

[0427] That is, like the folded outer surface of the base material, unlike the inner surface, the other surface does not generate compressive stress. Therefore, the size of the first hole formed on the other surface does not vary with the magnitude of curvature, but can be formed to have the same size.

[0428] Meanwhile, the embodiments are not limited to this, and by offsetting the position of the second through hole in the folding axis direction according to the curvature, another surface of the base material can be formed, similar to the one surface mentioned above.

[0429] Reference Figures 35 to 37 The first hole H1 can be formed in the first region 1A (i.e., the folded region) where the first hinge portion HN1 and the second hinge portion HN2 are formed.

[0430] The first hole H1 can be formed such that each unit area of ​​the folded region has a different size. Specifically, the folded region may include regions having a first hole with a different size per unit area.

[0431] That is, for each region in the folded region, the size of the first hole H1 formed in the inner surface of the substrate material (i.e., a surface 1S of the substrate material) by the folded substrate material 100 can be formed to be different from each other.

[0432] Here, the size of each unit area of ​​the first hole H1 can be defined as the area forming the first hole H1 per unit area, and the increase of the size of each unit area of ​​the first hole H1 can also be defined as the increase of the size of the first hole or the increase of the number of the first holes.

[0433] At least two folded regions can be defined in the substrate material 100. For example, at least two folded regions can be defined in the substrate material 100 based on the curvature of the substrate material 100 formed by folding the substrate material 100.

[0434] Reference Figure 35 and Figure 37 The first region 1A of the substrate material 100 may include a first curvature region RA1 and a second curvature region RA2. That is, the first region 1A may include a first curvature region RA1 and a second curvature region RA2 with different sizes.

[0435] Due to reference Figure 35 and Figure 37 The shapes of the first hole, the first through hole, and the second through hole on a surface 1S described above are similar to those described above. Figure 32 and Figure 34 Similar or identical, descriptions omitted below.

[0436] Refer to 36 and Figure 37 The first curvature region RA1 and the second curvature region RA2 can have different radii of curvature. Specifically, the radius of curvature of the first curvature region RA1, which is closer to the folding axis, can be smaller than the radius of curvature of the second curvature region RA2, which is farther from the folding axis than the first curvature region RA1.

[0437] The size per unit area of ​​the first hole H1 formed in the first curvature region RA1 and the second curvature region RA2 can be different from each other. In detail, the size per unit area of ​​the first hole H1 formed in the first curvature region RA1 can be larger than the size per unit area of ​​the first hole H1 formed in the second curvature region RA2.

[0438] In other words, the distance d1 between the first holes H1 formed in the first curvature region RA1 can be smaller than the distance d2 between the first holes H1 formed in the second curvature region RA2.

[0439] That is, the first hole H1 formed in the first curvature region RA1 can be formed more densely, that is, it has a higher density than the first hole H1 formed in the second curvature region RA2.

[0440] Figure 37 It is along Figure 35 The cross-sectional view taken by line DD′ is a diagram showing the shape of the first hole passing through one surface 1S and another surface 2S.

[0441] Reference Figure 37 The first hole H1 may include a first through hole h1 passing through one surface 1S and a second through hole h2 passing through another surface 2S.

[0442] The first through hole h1 and the second through hole h2 can have an inner diameter IR and an outer diameter OR. That is, the outer diameter of the first through hole h1 and the second through hole h2 can be larger than the inner diameter.

[0443] The outer diameter of the first through hole h1 and the second through hole h2 can be from about 0.01 mm to about 10 mm.

[0444] In the first through hole h1 and the second through hole h2, a central axis passing through the center of each through hole can be defined. That is, in the first through hole h1 and the second through hole h2, a first central axis and a second central axis passing through the center of the outer diameter of each through hole can be defined.

[0445] In the first curvature region RA1, the positions of the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be close to the folding axis. That is, in the first curvature region RA1, the distance between the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be closer than the distance between the first central axis and the second central axis in the second curvature region RA2.

[0446] In other words, the first region may include the region where the distance between the centers of two adjacent first holes in the plurality of first holes is different, and the region where the distance between the centers of two adjacent second through holes in the plurality of first holes is different.

[0447] That is, in the first curvature region RA1, the positions of the first through hole h1 and the second through hole h2 can be changed such that as the position moves closer to the folding axis, the size of the first through hole h1 per unit area increases.

[0448] That is, in the first curvature region RA1, the distance between the first central axis C1 of the first through hole h1 and the second central axis C2 of the second through hole h2 can be offset to be closer than the distance between the first central axis and the second central axis in the second curvature region RA2.

[0449] In this case, the offset distance d3 of the center axis of the first through hole h1 and the offset distance d4 of the center axis of the second through hole h2 can satisfy the following equation 4.

[0450] [Equation 4]

[0451] 0.1t ≤ offset distance d3 of the center axis of the first through hole, and offset distance d4 of the center axis of the second through hole ≤ 10t

[0452] (Where t is the thickness of the substrate material)

[0453] The offset distance d3 of the first through hole h1 and the offset distance d4 of the second through hole h2 can be the same or different. That is, in the first curvature region RA1, the first through hole and the second through hole can be formed to be offset from each other by the same distance, so that the first central axis and the second central axis coincide with each other. Alternatively, in the first curvature region RA1, the first through hole and the second through hole can be formed to be offset by different distances to change the first central axis and the second central axis.

[0454] Therefore, the size per unit area of ​​the first hole formed on the folded inner surface (i.e., one surface and another surface of the substrate material) can differ in regions with different curvatures. Thus, in regions with small radii of curvature, the size per unit area of ​​the first hole can be formed to be larger, and in regions with large radii of curvature, the size per unit area of ​​the first hole can be formed to be relatively smaller.

[0455] Therefore, in the display substrate according to the embodiment, when the substrate material is in a folded state, by minimizing the distribution of compressive stress that varies according to the curvature, a display substrate with improved folding reliability can be achieved.

[0456] In addition, by making the size of the holes per unit area similar in one surface region and another surface region, stress in each curvature region can be effectively distributed during folding.

[0457] That is, the proportion of holes that can disperse compressive stress in regions with small radii of curvature is formed to be greater than the proportion of holes in regions with large radii of curvature, thereby more effectively dispersing the compressive stress generated on the folded inner surface of the substrate material.

[0458] Meanwhile, holes may also be formed in the unfolded area of ​​the display substrate according to the embodiment.

[0459] Reference Figures 38 to 41 In the display substrate, holes can be formed in the second region of the substrate material 100.

[0460] Specifically, the substrate material 100 may include a first region 1A and a second region 2A, in which a first hole H1 may be formed and a second hole H2 may be formed.

[0461] Since the first hole H1 formed in the first region 1A is the same as in the above embodiment, the following description is omitted. That is, referring to... Figures 14 to 19 The first hole in the above embodiment can be with Figures 20 to 23 Combined with the other embodiments shown below.

[0462] Multiple second holes H2, spaced apart from each other, can be formed in the second region 2A.

[0463] The second hole H2 may overlap with one surface and the other surface of the second region 2A of the substrate material 100, to be formed to pass through the substrate material 100, or to be formed to pass through only one surface.

[0464] The dimensions of the second hole H2 can be the same as or similar to those of the first hole H1. Alternatively, the outer and inner diameters of the second hole H2 can differ from those of the first hole H1.

[0465] Specifically, refer to Figures 38 to 41 The size of the second hole H2 can be smaller than the size of the first hole H1.

[0466] Therefore, by making the size or proportion of the holes in the second region smaller than the size or proportion of the holes in the first region, it is possible to prevent the second region from bending together when the base material is folded.

[0467] Alternatively, refer to Figures 38 to 41 The size per unit area of ​​the second hole H2 can be smaller than the size per unit area of ​​the first hole in the first curvature region and the second curvature region of the first region.

[0468] Therefore, the size of the second hole H2 per unit area is smaller than the size of the first hole per unit area in the first region, so that the folded region and the unfolded region can be spaced apart, and since no hinge is formed in the second region, the first region can be warped by a smaller force than the second region.

[0469] That is, according to Figures 38 to 41 In the display substrate, holes can be formed not only in curved areas but also in non-curved areas.

[0470] That is, pores can be formed in all areas of the substrate material.

[0471] Therefore, by reducing the difference between the deformation of the first region due to heat and the deformation of the second region due to heat, it is possible to prevent the display substrate from warping or twisting.

[0472] Specifically, when the difference in deformation between the first and second regions due to heat is too large, the display substrate may warp or twist. Consequently, fragmentation may occur in the substrate material in the boundary region between the first and second regions.

[0473] Therefore, in the display substrate according to the embodiment, by also forming a hole in the second region, damage to the display substrate due to thermal deformation can be prevented.

[0474] In the display substrates according to the third and fourth embodiments, the size of the hole per unit area can be different depending on the degree of folding (i.e., the size of the radius of curvature) in the folded area of ​​the substrate material.

[0475] Therefore, it can effectively disperse the compressive stress that varies for each region depending on the curvature of the inner surface of the fold.

[0476] That is, by making the size of each unit area of ​​the hole different according to the magnitude of the generated compressive stress, the compressive stress in the part with a large compressive stress can be effectively dispersed, thus preventing the substrate material from cracking due to compressive stress.

[0477] Figure 42 This is a diagram used to describe an embodiment of which a display substrate according to an embodiment is applied.

[0478] Reference Figure 42 The display substrate according to the embodiment can be applied to a display device that displays a display.

[0479] For example, the display substrate according to the embodiment can be applied to display devices such as mobile phones and tablet computers.

[0480] This type of display substrate can be used in display devices such as flexible, curved, or foldable mobile phones or tablets.

[0481] Display substrates can be used in display devices such as flexible, curved, or foldable mobile phones or tablets, thus preventing stress damage to the substrate material in display devices that are repeatedly folded or unfolded.

Claims

1. A foldable display substrate based on a folding axis, comprising: The substrate material has a longitudinal direction and a short direction, and includes one surface and another surface, as well as a first region and a second region; A hole, the hole passing through one surface and the other surface of the substrate material; as well as A groove is formed on the other surface of the base material. The holes include a plurality of first holes formed in the first region. The first region is positioned between the two second regions. The first hole includes multiple through holes. The first hole is formed as a plurality of rows including the through hole extending in the short direction. The number of through holes in the plurality of rows decreases as they move away from the folding axis. The through holes include a first through hole, a second through hole, and a third through hole. The plurality of rows includes rows comprising a plurality of first through holes, rows comprising a plurality of second through holes, and rows comprising a plurality of third through holes. The row comprising multiple third through holes is positioned closest to the folding axis. The row including multiple second through holes is disposed between the row including multiple first through holes and the row including multiple third through holes. The plurality of first through holes, the plurality of second through holes, and the plurality of third through holes are spaced apart from the two end regions of the substrate material in the short direction. The distance between the plurality of rows and the end regions of the substrate material in the short direction increases with distance from the folding axis. The plurality of first through holes includes the first-1 through hole closest to one end region in the short direction of the substrate material. Among them, the plurality of second through holes includes the second-1st through hole closest to the one end region. Among them, the plurality of third through holes includes the third-1st through hole closest to the one end region. Wherein, the first center of the first through hole in the short direction is spaced apart from the one end region by a first distance in the short direction. Wherein, the second center of the second-1 through hole in the short direction is spaced apart from the one end region by a second distance in the short direction. Wherein, the third center of the third-1 through hole in the short direction is spaced apart from the one end region by a third distance in the short direction. Wherein, the first distance is greater than each of the second distance and the third distance. Wherein, the second distance is greater than the third distance. The groove includes a plurality of grooves, which are formed on the other surface of the first region and between the one end region and the first-1 through hole and between the one end region and the second-1 through hole. The number of grooves formed between one end region and the first-1 through hole is greater than the number of grooves formed between one end region and the second-1 through hole. Each of the through holes includes: A first hole penetrates the surface; and The second hole penetrates the other surface. The first central axis of the first hole and the second central axis of the second hole are offset from each other in the direction toward the folding axis. Wherein, the offset distance between the first central axis and the second central axis increases toward the folding axis, and Wherein, the offset distance satisfies: 0.1t ≤ offset distance ≤ 10t Where t is the thickness of the substrate material.

2. The display substrate according to claim 1, in, The number of third through holes in a row that includes the plurality of third through holes is greater than the number of second through holes in a row that includes the plurality of second through holes. The number of second through holes in a row including the plurality of second through holes is greater than the number of first through holes in a row including the plurality of first through holes.

3. The display substrate according to claim 2, wherein, The size of the third through hole is larger than the size of the second through hole.

4. The display substrate according to claim 2, wherein, The size of the second through hole is larger than the size of the first through hole, and The difference between the size of the second through hole and the size of the first through hole is between 0.8t and 1.1t. Where t is the thickness of the substrate material.

5. The display substrate according to claim 2, wherein, The third through holes in the row including the plurality of third through holes are of the same size, and The plurality of third through holes are offset in the same direction toward the folding axis.

6. The display substrate according to claim 2, wherein, The second through holes in the row including the plurality of second through holes are of the same size, and The plurality of second through holes have the same offset distance between the first central axis and the second central axis.

7. The display substrate according to claim 2, wherein, The first through holes in the row including the plurality of first through holes are of the same size.

8. The display substrate according to claim 4, wherein, The first distance and the second distance are greater than the short-direction spacing of the through holes in the plurality of rows.

9. The display substrate according to claim 1, wherein, The through-hole is not formed in the second region.

10. The display substrate according to claim 1, wherein, The substrate material includes a plurality of hinges, the plurality of hinges being defined as holes formed at the two end regions in the short direction of the substrate material. The hinge portion is located at the two end regions in the short direction.

11. The display substrate according to claim 10, wherein, The hinge portion is provided in the first region but not in the second region.

12. The display substrate according to claim 10, wherein, The hinge portion is spaced apart from the through hole.

13. The display substrate according to claim 10, wherein, The number of hinges is less than the number of through holes.

14. The display substrate according to claim 1, wherein, The size of the through holes in the plurality of rows decreases as they move away from the folding axis.

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