KR20200087470A - Substrate for display - Google Patents

Abstract

According to an embodiment of the present invention, a substrate for a display comprises: a substrate having a long direction and a short direction, including one surface and the other surface, and including a first region and a second region; and a hole penetrating through the one surface and the other surface of the substrate. The first region is defined as a folding region folded to face a region of the one surface. The second region is defined as an unfolding region. The hole includes a first hole formed in the first region. The first hole includes at least three first holes having different sizes in the long direction of the substrate. The degree of freedom in design of the substrate for a display may be increased.

Description

Display Substrate{SUBSTRATE FOR DISPLAY}

The embodiment relates to a substrate for a display.

Recently, there is an increasing demand for a flexible display device that is easy to carry a variety of applications and capable of displaying images on a larger screen when carrying.

The flexible display may be folded or bent when it is carried or stored, and may be implemented in an expanded state when displaying an image. Accordingly, it is possible to increase the image display area and facilitate the user's portability.

After the flexible display device is folded or bent, a process of unfolding it again may be repeated.

Accordingly, the substrate of the display device is required strength and elasticity, and such folding and returning should not cause cracks or deformation in the substrate.

On the other hand, when the substrate of the display device is folded, it may have different curvature sizes for each folded region. Accordingly, different compressive stresses act on each region according to different sizes of curvature generated in each region.

In particular, depending on the folding direction, the folding outer surface may generate tensile stress, which may cancel the residual compressive stress, but in the case of the inner surface, the compressive stress occurs, and the residual compressive stress and the compressive stress act together to create a folding inner surface. It can be damaged or cracked by compressive stress.

Accordingly, cracks may be generated in the substrate during folding in a region where the compressive stress is large, and when the substrate is bent, a curvature size restriction occurs, so that the degree of folding of the substrate, that is, the degree of freedom in design may be reduced.

Accordingly, there is a need for a display substrate having a new structure capable of improving reliability of a display substrate applied to the flexible display device and improving design freedom.

Embodiments are intended to provide a substrate for a display having improved reliability and design freedom.

A substrate for a display according to an embodiment includes a substrate having a long direction and a short direction, including one surface and the other surface, and including a first area and a second area; And a hole penetrating one surface and the other surface of the substrate, wherein the first area is defined as a folding area in which the one-sided area faces, the second area is defined as an unfolding area, and the hole is the A first hole is formed in the first region, and the first hole includes at least three first holes having different sizes in the longitudinal direction of the substrate.

The display substrate according to the embodiment may vary the size and fraction of the hole according to the degree of folding, that is, the size of the curvature in the area where the substrate is folded.

Accordingly, it is possible to effectively disperse the compressive stress depending on the curvature on the inner side of the folding.

That is, by varying the size of the hole or the fraction of the hole for each area according to the size of the curvature, that is, the size of the compressive stress generated, it can effectively disperse it in the area where the compressive stress acts largely, thereby preventing cracking of the substrate due to the compressive stress. can do.

In addition, since the hole size and the fraction are different according to the size of the curvature, and the constraints according to the size of the curvature are reduced, folding as much as the desired curvature is possible, so that the design freedom of the display substrate can be improved.

1 is a view showing a perspective view of a display substrate according to an embodiment.
2 is a view showing a side view of a display substrate according to an embodiment.
3 is a view showing a top view of one surface of a display substrate according to an embodiment.
4 is a view showing a top view of the other surface of the display substrate according to the embodiment.
5 is a view showing another top view of one surface of a display substrate according to an embodiment.
6 is a view showing another top view of the other surface of the display substrate according to the embodiment.
7 to 10 are views showing another top view of one surface and the other surface of the display substrate according to the embodiment.
11 is a view illustrating a side view of a display substrate according to another embodiment.
12 is a view showing a top view of one surface of a display substrate according to another embodiment.
13 is a view showing a top view of the other surface of a display substrate according to another embodiment.
14 is a view showing another top view of one surface of a display substrate according to another embodiment.
15 is a view showing another top view of the other surface of the display substrate according to another embodiment.
16 to 19 are views showing another top view of one surface and the other surface of a display substrate according to another embodiment.
20 is a view for explaining an application example of a display substrate according to an embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to some embodiments described, but may be implemented in various different forms, and within the scope of the technical spirit of the present invention, one or more of its components between embodiments may be selectively selected. It can be used by bonding and substitution.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless explicitly defined and described, can be generally understood by those skilled in the art to which the present invention pertains. It can be interpreted as meaning, and commonly used terms, such as predefined terms, may interpret the meaning in consideration of the contextual meaning of the related technology.

In addition, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention. In the present specification, a singular form may also include a plural form unless specifically stated in the phrase, and when described as “at least one (or more than one) of A and B, C”, A, B, and C may be combined. It can contain one or more of all possible combinations.

In addition, in describing components of the embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the component from other components, and the term is not limited to the nature, order, or order of the component.

And, when a component is described as being'connected','coupled' or'connected' to another component, the component is not only directly connected, coupled or connected to the other component, but also to the component It may also include a case of'connected','coupled' or'connected' due to another component located between the other components.

In addition, when described as being formed or disposed in the "top (top) or bottom (bottom)" of each component, the top (top) or bottom (bottom) is one as well as when the two components are in direct contact with each other It also includes a case in which another component described above is formed or disposed between two components.

In addition, when expressed as “up (up) or down (down)”, it may include the meaning of the downward direction as well as the upward direction based on one component.

Hereinafter, a substrate for a display according to an embodiment will be described with reference to the drawings.

1 to 8, a substrate for a display according to an embodiment includes a substrate 100.

The substrate 100 may include metal, metal alloy, plastic, composite material (eg, carbon fiber reinforced plastic, magnetic or conductive material, glass fiber reinforced material, etc.), ceramic, sapphire, glass, and the like.

In the case of the substrate 100 having such rigidity, when bending in one direction, a problem may occur in that the substrate is damaged by folding or bending due to tensile stress or compressive stress caused by bending.

In addition, since the curvature of the folding region is limited by tensile stress or compressive stress generated when the substrate 100 is bent in one direction, a problem in design freedom of the substrate may be deteriorated.

The substrate for a display according to an embodiment may prevent the substrate from being damaged by such folding or bending, and may loosen restrictions according to curvature to improve design freedom.

Referring to FIG. 1, the substrate 100 may be bent in one direction.

In detail, the substrate 100 may include one surface 1S and the other surface 2S opposite to the one surface 1S. The substrate 100 may have the one surface 1S or the other surface 2S facing each other. Can be bent.

In the following description, it will be mainly described that the substrate 100 is bent in a direction in which the surfaces 1S face each other as shown in FIG. 1.

The first region 1A and the second region 2A may be defined in the substrate 100. The first region 1A and the second region 2A may be regions defined when the substrate 100 is bent in a direction in which the one surfaces 1S face each other.

In detail, the substrate 100 is bent in one direction, and the substrate 100 is a first region 1A, which is a folding region (folding region), and a second region, which is a non-folding region (unfolding region) ( 2A).

In detail, referring to FIGS. 3 to 10, the substrate 100 may include a first region 1A, which is a region in which the substrate 100 is bent. In addition, the substrate 100 may not be bent, and may include a second region 2A disposed adjacent to the first region 1A.

For example, the second region 2A may be formed on the left and right sides of the first region 1A, respectively, based on the direction in which the substrate 100 is bent.

The first region 1A and the second region 2A may be formed on the same substrate 100. That is, the first region 1A and the second region 2A may be integrally formed with each other without being separated on the same single substrate 100.

The first region 1A and the second region 2A may have different sizes. In detail, the size of the second region 2A may be larger than the size of the first region 1A.

Although the drawing shows that the first region 1A is located at the central portion of the substrate 100, the embodiment is not limited thereto, that is, the first region 1A is one end of the substrate 100 and It can be located in the distal region. That is, the first region 1A may be positioned at one end and one end region of the substrate 100 so that the size of the second region 2A is asymmetric.

A hole may be formed in the first region 1A. In detail, a plurality of first holes H1 which are spaced apart from each other may be formed in the first region 1A. The first hole H1 may be formed through the substrate 100. In detail, the first hole H1 may be formed through one surface 1S and the other surface 2S of the substrate 100.

That is, the first hole H1 may be formed through the one surface 1S positioned inside the folding direction and the other surface 2S arranged outside the folding direction.

The first holes H1 may be formed in a regular pattern in the first region 1A, or the first holes H1 may be formed in an irregular pattern in the first region 1A. .

The first hole H1 may be formed while having a curved surface. In detail, the first hole H1 may be formed in a shape having a curved surface such as an elliptical shape, a hemispherical shape, or a circular shape.

However, the embodiment is not limited thereto, and the first hole H1 may be formed in a polygonal shape such as a triangle or a square.

2 is a view illustrating a side view of a display substrate according to an embodiment.

Referring to FIG. 2, the substrate 100 may be folded in one direction. In detail, the one surface (1S) along the folding axis may be folded in a direction facing each other.

As the substrate 100 is folded in one direction, a first region 1A and a second region 2A may be formed in the substrate 100. That is, a folding region formed as the substrate 100 is folded in one direction and an unfolding region positioned at both ends of the folding region may be formed on the substrate 100.

The folding area may be defined as an area where curvature R is formed, and the unfolding area may be defined as an area where curvature R is not formed or the curvature is close to zero.

Referring to FIG. 2, the substrate 100 is folded in one direction, and may be formed in order of an unfolding area, a folding area, and an unfolding area.

The substrate for a display according to an embodiment may improve reliability and design freedom of a display substrate by varying the size and fraction of holes formed in the folding region.

3 and 4 are views showing one surface and the other surface of the display substrate according to the embodiment. That is, FIG. 3 is a view showing a top view of the inner side of the folding when the base 100 is folded, and FIG. 4 is a view showing a top view of the outer side of the folding when the base 100 is folded. to be.

Referring to FIG. 3, the first region 1A and the second region 2A may be formed in the substrate 100. That is, a folding region formed as the substrate 100 is folded in one direction and an unfolding region positioned at both ends of the folding region may be formed on the substrate 100. That is, the first region 1A may be a folding region, and the second region 2A may be an unfolding region.

The substrate 100 may have a length in a long direction and a length in a unidirectional direction.

The second region 2A may extend from the first region 1A, and the second region 2A is located on the outer side of the substrate 100 based on the length of the substrate 100 in the longitudinal direction. can do.

The folding area may be defined as an area where curvature R is formed, and the unfolding area may be defined as an area where curvature is not formed or a curvature is close to zero.

The folding area may be defined as an area between the first hinge part HN1 and the second hinge part HN2.

In detail, the hinge parts may be defined as a point where folding starts in the substrate 100. That is, folding of the substrate 100 starts at the first hinge portion HN1 and the second hinge portion HN2, so that one surface 1S of the substrate 100 can be folded in a direction facing each other. .

The first hinge part HN1 and the second hinge part HN2 may be located at an end region of the substrate 100. In detail, the first hinge portion HN1 and the second hinge portion HN2 may be located at both end regions in one direction among the end regions of the substrate 100.

In addition, the first hinge portion HN1 and the second hinge portion HN2 may be formed by penetrating both unidirectional end regions of the substrate 100. That is, the first hinge part HN1 and the second hinge part HN2 may be defined as holes h formed by passing through both end regions in one direction of the substrate 100.

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 to form a unidirectional end region of the substrate 100. It may be defined as a hole formed by opening.

The shape of the hole h may be the same as or different from the shape of the first hole H1. For example, the hole h may be formed while having a curved surface. In detail, the hole h may be formed in a shape having a curved surface such as an elliptical shape, a hemispherical shape, or a circular shape.

However, the embodiment is not limited thereto, and the hole h may be formed in a polygonal shape such as a triangle or a square.

Referring to FIG. 3, the first hole H1 may be formed in a first region 1A, that is, a folding region, between the first hinge portion H1 and the second hinge portion H2.

The first hole H1 may include a plurality of holes having different sizes in the folding area. In detail, the first hole H1 may include at least three or more holes having different sizes in the longitudinal direction of the substrate in the folding area.

In FIG. 3 and the following drawings, three holes of different sizes are illustrated, but the embodiment is not limited thereto, and may include less than or more than three holes according to a change in the curvature size.

For example, the first hole H1 is a 1-1 hole H1-1, a 1-2 hole H1-2, and a 1-3 hole H1-3 disposed in the folding area. The 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) may be formed in different sizes. .

In detail, the first region 1A of the substrate 100 may include regions having different curvature sizes. Here, the size of the curvature means the degree of bending of the substrate, that is, the more the substrate is bent, the larger the curvature size.

In detail, the first region 1A of the substrate includes a first-1 region (1-1A) having a first curvature R1, a first 1-2 region (1-2A) having a second curvature R2, and A third 1-3 region 1-3A having a third curvature R3 may be included.

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

The 1-1 hole (H1-1) and the first are respectively in the 1-1 region (1-1A), the 1-2 region (1-2A), and the 1-3 region (1-3A). A -2 hole H1-2 and the first 1-3 hole H1-3 may be formed.

In this case, the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may have different sizes. Here, the size of the hole may be defined as the diameter or area of the hole.

That is, when the hole is formed in a circular shape, the size of the hole may be defined as the size of the outer diameter of the hole, that is, the maximum diameter in the long direction from one surface or the other surface on which the holes are formed.

Alternatively, when the hole is formed in a shape other than a circular shape, the size of the hole may be defined as the size of the outer diameter of the hole, that is, the area of the hole measured on one surface or the other surface on which the holes are formed.

Hereinafter, the case where the hole is formed in a circular shape will be mainly described.

In detail, the size of the 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) is the 1-1 area (1-1A) ), the 1-2th region 1-2A and the 1-3th region 1-3A may vary depending on the curvature size.

In detail, the size of the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be proportional to the size of the curvature. That is, the size of the first hole may be large in a region having a large curvature, and the size of the first hole may be small in a region having a small curvature.

Accordingly, the display substrate according to the embodiment may minimize the distribution of compressive stress that changes according to the size of the curvature when the substrate is in the folded state, thereby realizing a display substrate with improved folding reliability.

That is, in a region having a large curvature, the size of a hole capable of dispersing compressive stress is formed larger than that of a region having a small curvature, thereby effectively dispersing the compressive stress.

Meanwhile, the difference in the maximum diameter of the first holes H1 may satisfy Equation 1 below.

[Equation 1]

0.8t ≤ difference in maximum diameter of the first holes H1 ≤ 1.1t

(Where t is the thickness of the substrate)

That is, the size of the 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) is 0.8 times to 1.1 times the thickness of the substrate It can be changed in size.

Meanwhile, the thickness t of the substrate 100 may be about 0.01 mm to 2 mm. When the thickness of the substrate 100 is less than about 0.1 mm, it is easy to bend or bend the substrate 100, but the stiffness of the substrate 100 is reduced, and may be easily damaged by external impact or the like. In addition, when the thickness of the substrate 100 exceeds about 2 mm, when the substrate 100 is bent or bent by the thickness of the substrate 100, a stress generated accordingly occurs, thereby damaging the substrate. Or, the bending size of the substrate, that is, the curvature may be limited.

When the difference between the maximum diameters of the first holes H1 is less than 0.8 times the thickness of the substrate, reliability cannot be reduced because the compressive stress according to the curvature size cannot be effectively dispersed. In addition, when the difference in the maximum diameter of the first holes H1 is 1.1 times or more with respect to the substrate thickness, the strength of the substrate 100 may be deteriorated.

In addition, the difference between the maximum and minimum values of the first holes H1 may satisfy Equation 2 below.

[Equation 2]

0.2t ≤ difference between the maximum and minimum values of the first holes (H1)

(Where t is the thickness of the substrate)

When the difference between the maximum value and the minimum value of the first holes H1 is less than 0.2 times the thickness of the substrate, the compressive stress according to the size of the curvature cannot be effectively dispersed, and reliability may be deteriorated.

4 is a view showing a top view of the other surface of the substrate 100. That is, it is a view showing a top view of the outside, not the inside of the folding direction.

Referring to FIG. 4, since the first hole H1 is formed through one surface and the other surface of the substrate 100, the first hole H1 formed on the other surface of the substrate 100 is also one surface The first region 1A between the first hinge portion H1 and the second hinge portion H2 may be formed in the same manner as the position of the first hole formed in the first hinge portion H2.

The size of the first hole H1 formed on the other surface may be formed to be the same size as the first hole formed on the one surface.

That is, the other surface is a folding outer surface of the substrate, and unlike the inner surface, compressive stress does not occur. Therefore, the size of the first hole formed on the other surface may not be changed according to the size of the curvature, and may be formed in the same size.

However, the embodiment is not limited thereto, and the size of the first hole may be differently formed on the other surface of the substrate according to the size of the curvature as described above. Alternatively, a first hole is not formed on the other surface of the substrate, and a groove may be formed on the one surface, such as the shape and size of the first hole.

In addition, the first hole H1 may have a size of an outer diameter formed on one surface and a size of an outer diameter formed on the other surface.

For example, the size of the outer diameter formed on the other surface of the first hole H1 may be larger than the size of the outer diameter formed on the one surface. Accordingly, when folding the substrate 100 in a direction facing the one side, the size of the outer diameter formed on the inner side of the folding is smaller than the size of the outer diameter formed on the outer side of the folding, so the base 100 is easy Can be folded.

Meanwhile, in the display substrate according to the embodiment, a fraction of the first hole may be changed, not the size of the first hole in the folding area.

5 and 6, the first hole H1 may be formed in the first region 1A, that is, the folding region, between the first hinge portion H1 and the second hinge portion H2. have.

The first hole H1 may be formed in a different fraction for each area in the folding area. In detail, the folding region may include at least three or more regions having different first hole fractions in the longitudinal direction of the substrate.

In FIG. 5 and the following drawings, three holes of different fractions are illustrated, but the embodiment is not limited thereto, and may include less than or three holes according to a change in the curvature size.

Here, the fraction of the first hole may be defined as an area in which the first hole is formed per unit area, and the larger the formation area of the first hole, the larger the fraction of the first hole. That is, the large fraction of the first hole can also be defined as having a large number of first holes.

For example, the first hole H1 is a 1-1 hole H1-1, a 1-2 hole H1-2, and a 1-3 hole H1-3 disposed in the folding area. The 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) may be formed at different fractions. .

In detail, the first region 1A of the substrate 100 may include regions having different curvature sizes. In detail, the first region 1A of the substrate includes a first-1 region (1-1A) having a first curvature R1, a first 1-2 region (1-2A) having a second curvature R2, and A third 1-3 region 1-3A having a third curvature R3 may be included.

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

The 1-1 hole (H1-1) and the first are respectively in the 1-1 region (1-1A), the 1-2 region (1-2A), and the 1-3 region (1-3A). A -2 hole H1-2 and the first 1-3 hole H1-3 may be formed.

In this case, the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be formed at different fractions. In detail, the fraction of the 1-1 hole (H1-1), the 1-2 hole (H1-2), and the 1-3 hole (H1-3) is the 1-1 area (1-1A) ), the 1-2th region 1-2A and the 1-3th region 1-3A may vary depending on the curvature size.

In detail, the fraction of the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be proportional to the magnitude of the curvature. That is, in the region having a large curvature, the fraction of the first hole may be large, and in the region having a small curvature, the fraction of the first hole may be small.

Accordingly, the display substrate according to the embodiment may minimize the distribution of compressive stress that changes according to the size of the curvature when the substrate is in the folded state, thereby realizing a display substrate with improved folding reliability.

In other words, in a region having a large curvature, a hole fraction capable of dispersing compressive stress is formed larger than a region having a small curvature, so that the compressive stress can be more effectively dispersed.

6 is a view showing a top view of the other surface of the substrate 100. That is, it is a view showing a top view of the outside, not the inside of the folding direction.

Referring to FIG. 6, since the first hole H1 is formed through one surface and the other surface of the substrate 100, the first hole H1 formed on the other surface of the substrate 100 is also one surface The first region 1A between the first hinge portion H1 and the second hinge portion H2 may be formed in the same manner as the position of the first hole formed in the first hinge portion H2.

The size of the first hole H1 formed on the other surface may be formed at the same fraction as the first hole formed on the other surface.

Accordingly, the first holes formed on one surface may be partially formed through the other surface, and partially formed through only one surface.

That is, the other surface is a folding outer surface of the substrate, and unlike the inner surface, compressive stress does not occur. Therefore, the fraction of the first hole formed on the other surface may not be changed according to the size of the curvature and may be formed at the same fraction.

However, the embodiment is not limited thereto, and the first hole may be formed differently on the other surface of the substrate according to the magnitude of the curvature as described above. Alternatively, a first hole is not formed on the other surface of the substrate, and may be formed as a groove as in the shape and size of the first hole on only one surface.

In addition, in the first hole H1, a fraction of a first hole formed on one surface and a fraction of a first hole formed on the other surface may be different from each other.

For example, the first hole H1 may have a greater fraction of the first hole formed on the other surface than that of the first hole formed on the one surface. Accordingly, when folding the substrate 100 in a direction facing the one surface, since the fraction of the first hole formed in the folding inner surface is smaller than the fraction of the first hole formed in the folding outer surface, the substrate 100 Can be easily folded.

Meanwhile, a hole may be formed in the unfolding region of the display substrate according to the embodiment.

Referring to FIGS. 7 to 10, holes in the second region of the substrate 100 may be formed in the display substrate.

In detail, the substrate 100 includes a first region 1A and a second region 2A, a first hole H1 is formed in the first region 1A, and the second region 2A. The second hole H2 may be formed.

Since the first holes H1 formed in the first region 1A are the same as the above-described embodiment, the following description is omitted. That is, the first hole of the embodiment described with reference to FIGS. 3 to 6 may be combined with other embodiments as shown in FIGS. 7 to 10 below.

A plurality of second holes H2 spaced from each other may be formed in the second region 2A.

The second hole H2 may be formed by overlapping each other on one surface and the other surface of the second region 2A of the substrate 100 and passing through the substrate 100 or through only one surface.

The second hole H2 may be different from the size of the first hole H1. Alternatively, the second hole H2 may be different from the fraction of the first hole H1.

In detail, referring to FIGS. 7 and 8, the size of the second hole H2 may be different from the size of the first hole H1. In detail, the size of the second hole H2 may be smaller than the size of one of the plurality of first holes having different sizes. Alternatively, referring to FIGS. 9 and 10, the second hole H2 The fraction of may be different from the fraction of the first hole H1. In detail, the fraction of the second hole H2 may be smaller than a fraction of one of a plurality of regions having different fractions.

Accordingly, holes in the second region may have a smaller size and fraction than holes in the first region, so that when the substrate is folded, the second region may be prevented from bending together.

That is, in the display substrate according to FIGS. 7 to 10, holes may be formed in an area that is not bent in addition to the area that is bent.

That is, holes may be formed in all regions of the substrate.

Accordingly, a difference between deformation due to heat in the first region and deformation due to heat in the second region may be alleviated to prevent warpage or distortion of the display substrate.

In detail, when the difference in deformation due to heat in the first region and the second region becomes too large, the substrate for display may be warped or distorted, and accordingly, the substrate in the boundary region between the first region and the second region may be Cracking may occur.

Accordingly, the display substrate according to the embodiment may form holes in the second area to prevent damage to the display substrate due to thermal deformation.

Hereinafter, a substrate for a display according to another embodiment will be described with reference to FIGS. 11 to 19.

Referring to FIG. 11, the substrate 100 may be folded in one direction. In detail, the one surface (1S) may be folded in a direction facing each other.

As the substrate 100 is folded in one direction, a first region 1A and a second region 2A may be formed in the substrate 100. That is, a first region formed as the substrate 100 is folded in one direction and a second region positioned at both ends of the first region may be formed on the substrate 100.

The first area may be a folding area FA and an unfolding area UFA. Further, the second region may be an unfolding region (UFA).

That is, the display substrate according to another embodiment has two folding axes, and one region may include both the folding area FA and the unfolding area UFA.

The folding area may be defined as an area where curvature R is formed, and the unfolding area may be defined as an area where curvature R is not formed or the curvature is close to zero.

That is, the size of the folding area of the display substrate according to another embodiment may be smaller than the size of the folding area of the display substrate according to the above-described embodiment.

That is, referring to FIG. 11, the substrate 100 is folded in one direction, and may be formed in order of an unfolding area, a folding area, an unfolding area, a folding area, and an unfolding area.

That is, the design of the display substrate can be freely modified by controlling the size and fraction of the first hole described below.

12 and 13 are views illustrating one surface and the other surface of a display substrate according to another embodiment. That is, FIG. 12 is a view showing a top view of the inner side of the folding when the base 100 is folded, and FIG. 13 is a view showing a top view of the outer side of the folding when the base 100 is folded. to be.

Referring to FIG. 12, the first region 1A and the second region 2A may be formed in the substrate 100.

The first area 1A may include a folding area FA and an unfolding area UFA. The folding area FA may be defined as an area in which the curvature R is formed, and the unfolding area UFA may be defined as an area in which a curvature is not formed or a curvature is close to zero.

The folding area of the first area 1A is an area between the first hinge part HN1 and the second hinge part HN2 and an area between the third hinge part HN3 and the fourth hinge part HN4. Can be defined. Also, the unfolding region of the first region 1A may be defined as a region between the second hinge portion HN1 and the third hinge portion HN3.

.

In detail, the hinge parts may be defined as a point where folding starts in the substrate 100. That is, folding of the substrate 100 starts at the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4, and thus the substrate ( One surface 1S of 100) may be folded in an opposite direction.

The first hinge part HN1, the second hinge part HN2, the third hinge part HN3, and the fourth hinge part HN4 may be located at an end region of the substrate 100. In detail, the first hinge portion HN1, the second hinge portion HN2, the third hinge portion HN3, and the fourth hinge portion HN4 are provided at both end regions in one direction among the end regions of the substrate 100. Can be located.

In addition, the first hinge part HN1, the second hinge part HN2, the third hinge part HN3, and the fourth hinge part HN4 have both end regions in one direction among the end regions of the substrate 100. It can be formed through. That is, the first hinge part HN1, the second hinge part HN2, the third hinge part HN3, and the fourth hinge part HN4 have both end regions in one direction among the end regions of the substrate 100. It may be defined as a hole (h) formed through.

That is, the first hinge part HN1, the second hinge part HN2, the third hinge part HN3 and the fourth hinge part HN4 are in contact with the unfolding area of the first area 1A. It may be defined as a hole formed between the second regions 2A and formed by opening an end region of the substrate 100.

The shape of the hole h may be the same as or different from the shape of the first hole H1. For example, the hole h may be formed while having a curved surface. In detail, the hole h may be formed in a shape having a curved surface such as an elliptical shape, a hemispherical shape, or a circular shape.

However, the embodiment is not limited thereto, and the hole h may be formed in a polygonal shape such as a triangle or a square.

Referring to FIG. 12, the first hole H1 includes a first region 1A and the third hinge portion H3 between the first hinge portion H1 and the second hinge portion H2, and the The first region 1A between the fourth hinge portions H4 may be formed in the folding region.

The first hole H1 may include a plurality of holes having different sizes in the folding area. In detail, the first hole H1 may include at least three or more holes having different sizes in the longitudinal direction of the substrate in the folding area.

In FIG. 12 and the following drawings, three holes of different sizes are illustrated, but the embodiment is not limited thereto, and may include less than three or more than three holes having different sizes according to a change in the curvature size. .

For example, the first hole H1 is a 1-1 hole H1-1, a 1-2 hole H1-2, and a 1-3 hole H1-3 disposed in the folding area. The 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) may be formed in different sizes. .

In detail, the folding area FA of the first area 1A of the substrate 100 may include areas having different curvature sizes. In detail, the folding area FA of the first area 1A of the substrate includes a first-1 area (1-1A) having a first curvature R1 and a first 1-2 area having a second curvature R2. (1-2A) and a third 1-3 region (1-3A) having a third curvature (R3).

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

The 1-1 hole (H1-1) and the first are respectively in the 1-1 region (1-1A), the 1-2 region (1-2A), and the 1-3 region (1-3A). A -2 hole H1-2 and the first 1-3 hole H1-3 may be formed.

In this case, the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may have different sizes. In detail, the size of the 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) is the 1-1 area (1-1A) ), the 1-2th region 1-2A and the 1-3th region 1-3A may vary depending on the curvature size.

Here, the size of the hole may be defined as the diameter or area of the hole.

That is, when the hole is formed in a circular shape, the size of the hole may be defined as the size of the outer diameter of the hole, that is, the maximum diameter in the long direction from one surface or the other surface on which the holes are formed.

Alternatively, when the hole is formed in a shape other than a circular shape, the size of the hole may be defined as the size of the outer diameter of the hole, that is, the area of the hole measured on one surface or the other surface on which the holes are formed.

Hereinafter, the case where the hole is formed in a circular shape will be mainly described.

In detail, the size of the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be proportional to the size of the curvature. That is, the size of the first hole may be large in a region having a large curvature, and the size of the first hole may be small in a region having a small curvature.

Accordingly, the display substrate according to the embodiment may minimize the distribution of compressive stress that changes according to the size of the curvature when the substrate is in the folded state, thereby realizing a display substrate with improved folding reliability.

Meanwhile, the difference in the maximum diameter of the first holes H1 may satisfy Equation 1 below.

[Equation 1]

0.8t ≤ difference in maximum diameter of the first holes H1 ≤ 1.1t

(Where t is the thickness of the substrate)

That is, the size of the 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) is 0.8 times to 1.1 times the thickness of the substrate It can be changed in size.

Meanwhile, the thickness t of the substrate 100 may be about 0.01 mm to 2 mm. When the thickness of the substrate 100 is less than about 0.1 mm, it is easy to bend or bend the substrate 100, but the stiffness of the substrate 100 is reduced, and may be easily damaged by external impact or the like. In addition, when the thickness of the substrate 100 exceeds about 2 mm, when the substrate 100 is bent or bent by the thickness of the substrate 100, a stress generated accordingly occurs, thereby damaging the substrate. Or, the bending size of the substrate, that is, the curvature may be limited.

When the difference between the maximum diameters of the first holes H1 is less than 0.8 times the thickness of the substrate, reliability cannot be reduced because the compressive stress according to the curvature size cannot be effectively dispersed. In addition, when the difference in the maximum diameter of the first holes H1 is 1.1 times or more with respect to the substrate thickness, the strength of the substrate 100 may be deteriorated.

In addition, the difference between the maximum and minimum values of the first holes H1 may satisfy Equation 2 below.

[Equation 2]

0.2t ≤ difference between the maximum and minimum values of the first holes (H1)

(Where t is the thickness of the substrate)

When the difference between the maximum value and the minimum value of the first holes H1 is less than 0.2 times the thickness of the substrate, the compressive stress according to the size of the curvature cannot be effectively dispersed, and reliability may be deteriorated.

Meanwhile, a third hole H3 may be formed in the unfolding region of the first region. The third hole H3 may be formed to have the same or similar size differently from the first hole H. For example, the third hole H3 may be formed of holes having a uniform size of the same or different size from the first hole H.

13 is a view showing a top view of the other surface of the substrate 100. That is, it is a view showing a top view of the outside, not the inside of the folding direction.

Referring to FIG. 13, since the first hole H1 is formed through one surface and the other surface of the substrate 100, the first hole H1 formed on the other surface of the substrate 100 is also one surface The first region and the third hinge portion H3 and the fourth hinge portion H4 between the first hinge portion H1 and the second hinge portion H2 are the same as the position of the first hole formed in the ) In the first region, that is, the folding region.

The size of the first hole H1 formed in the folding area of the other surface may be formed to have the same size as the first hole formed on the one surface.

That is, the other surface is a folding outer surface of the substrate, and unlike the inner surface, compressive stress does not occur. Therefore, the size of the first hole formed on the other surface may not be changed according to the size of the curvature, and may be formed in the same size.

However, the embodiment is not limited thereto, and the size of the first hole may be differently formed on the other surface of the substrate according to the size of the curvature as described above. Alternatively, a first hole is not formed on the other surface of the substrate, and a groove may be formed on the one surface, such as the shape and size of the first hole.

In addition, the first hole H1 may have a size of an outer diameter formed on one surface and a size of an outer diameter formed on the other surface.

For example, the size of the outer diameter formed on the other surface of the first hole H1 may be larger than the size of the outer diameter formed on the one surface. Accordingly, when folding the substrate 100 in a direction facing the one side, the size of the outer diameter formed on the inner side of the folding is smaller than the size of the outer diameter formed on the outer side of the folding, so the base 100 is easy Can be folded.

Meanwhile, in the display substrate according to another embodiment, a fraction of the first hole may be changed, not the size of the first hole in the folding area.

14 and 15, the first hole H1 includes a first region between the first hinge portion H1 and the second hinge portion H2 and the third hinge portion H3 and the A fourth region between the fourth hinge portions H4, that is, the folding region FA may be formed.

The first hole H1 may be formed in a different fraction for each area in the folding area. In detail, the folding region may include at least three or more regions having different first hole fractions in the longitudinal direction of the substrate.

In FIG. 14 and the following drawings, three holes of different fractions are illustrated, but the embodiment is not limited thereto, and may include less than three or more than three holes having different fractions according to a change in the curvature size. .

Here, the fraction of the first hole may be defined as the formation area of the first hole, and the larger the formation area of the first hole, the larger the fraction of the first hole. That is, the large fraction of the first hole can also be defined as having a large number of first holes.

For example, the first hole H1 is a 1-1 hole H1-1, a 1-2 hole H1-2, and a 1-3 hole H1-3 disposed in the folding area. The 1-1 hole (H1-1), the 1-2 hole (H1-2) and the 1-3 hole (H1-3) may be formed at different fractions. .

In detail, the folding region of the first region of the substrate 100 may include regions having different curvature sizes. In detail, the folding region of the first region of the substrate includes a first-1 region (1-1A) having a first curvature R1, a first 1-2 region (1-2A) having a second curvature R2, and A third 1-3 region 1-3A having a third curvature R3 may be included.

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

The 1-1 hole (H1-1) and the first are respectively in the 1-1 region (1-1A), the 1-2 region (1-2A), and the 1-3 region (1-3A). A -2 hole H1-2 and the first 1-3 hole H1-3 may be formed.

In this case, the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be formed at different fractions. In detail, the fraction of the 1-1 hole (H1-1), the 1-2 hole (H1-2), and the 1-3 hole (H1-3) is the 1-1 area (1-1A) ), the 1-2th region 1-2A and the 1-3th region 1-3A may vary depending on the curvature size.

In detail, the fraction of the 1-1 hole H1-1, the 1-2 hole H1-2, and the 1-3 hole H1-3 may be proportional to the magnitude of the curvature. That is, in a region having a large curvature, the fraction of the first hole may be large, and in a region having a small curvature, the fraction of the first hole may be small.

Accordingly, the display substrate according to the embodiment may minimize the distribution of compressive stress that changes according to the size of the curvature when the substrate is in the folded state, thereby realizing a display substrate with improved folding reliability.

15 is a view showing a top view of the other surface of the substrate 100. That is, it is a view showing a top view of the outside, not the inside of the folding direction.

15, since the first hole H1 is formed through one surface and the other surface of the substrate 100, the first hole H1 formed on the other surface of the substrate 100 is also one surface The first region between the first hinge portion H1 and the second hinge portion H2 and the third hinge portion H3 and the fourth hinge portion H4 in the same manner as the position of the first hole formed in the ) In the first region, that is, the folding region.

The size of the first hole H1 formed on the other surface may be formed at the same fraction as the first hole formed on the other surface.

Accordingly, the first holes formed on one surface may be partially formed through the other surface, and partially formed through only one surface.

That is, the other surface is a folding outer surface of the substrate, and unlike the inner surface, compressive stress does not occur. Therefore, the fraction of the first hole formed on the other surface may not be changed according to the size of the curvature and may be formed at the same fraction.

However, the embodiment is not limited thereto, and the first hole may be formed differently on the other surface of the substrate according to the magnitude of the curvature as described above. Alternatively, a first hole is not formed on the other surface of the substrate, and may be formed as a groove as in the shape and size of the first hole on only one surface.

In addition, in the first hole H1, a fraction of a first hole formed on one surface and a fraction of a first hole formed on the other surface may be different from each other.

For example, the first hole H1 may have a greater fraction of the first hole formed on the other surface than that of the first hole formed on the one surface. Accordingly, when folding the substrate 100 in a direction facing the one surface, since the fraction of the first hole formed in the folding inner surface is smaller than the fraction of the first hole formed in the folding outer surface, the substrate 100 Can be easily folded.

Meanwhile, a hole may be formed in the unfolding region of the display substrate according to the embodiment.

16 to 19, holes in the second region of the substrate 100 may be formed in the display substrate.

In detail, the substrate 100 includes a first region 1A and a second region 2A, and a first hole H1 and a third hole H3 are formed in the first region 1A, A second hole H2 may be formed in the second region 2A.

Since the first hole H1 and the third hole H1 formed in the first region 1A are the same as the above-described embodiment, the following description is omitted. That is, the first hole and the third hole of the embodiment described above with reference to FIGS. 12 to 15 may be combined with other embodiments below.

A plurality of second holes H2 spaced from each other may be formed in the second region 2A.

The second hole H2 may be formed by overlapping each other on one surface and the other surface of the second area 2A of the substrate 100 to penetrate the substrate 100.

The second hole H2 may be different from the size of the first hole H1 and the third hole H3. Alternatively, the second hole H2 may be different from the fraction of the first hole H1.

In detail, referring to FIGS. 16 and 17, the size of the second hole H2 may be different from the size of the first hole H1 and the third hole H3. In detail, the size of the second hole H2 may be smaller than the size of one of the plurality of first holes having different sizes, or the size of the third hole H3.

Alternatively, referring to FIGS. 18 and 19, the fraction of the second hole H2 may be different from that of the first hole H1. In detail, the fraction of the second hole H2 may be different from the fraction of one of a plurality of regions having different fractions.

Accordingly, holes in the second region may have a smaller size and fraction than holes in the first region, so that when the substrate is folded, the second region may be prevented from bending together.

That is, in the display substrate according to FIGS. 16 to 19, holes may be formed in the second region that is not bent in addition to the first region.

Accordingly, a difference between deformation due to heat in the first region and deformation due to heat in the second region may be alleviated to prevent warpage or distortion of the display substrate.

In detail, when the difference in deformation due to heat in the first region and the second region becomes too large, the substrate for display may be warped or distorted, and accordingly, the substrate in the boundary region between the first region and the second region may be Cracking may occur.

Accordingly, the display substrate according to the embodiment may form holes in the second area to prevent damage to the display substrate due to thermal deformation.

The display substrate according to the embodiment may vary the size and fraction of the hole according to the degree of folding, that is, the size of the curvature in the area where the substrate is folded.

Accordingly, it is possible to effectively disperse the compressive stress that varies for each region depending on the size of the curvature on the inner side of the folding.

That is, by varying the hole size or fraction according to the size of the curvature, that is, the size of the compressive stress generated, it is possible to effectively disperse it in the area where the compressive stress acts largely, thereby preventing cracking of the substrate due to the compressive stress .

In addition, by varying the hole size and the fraction according to the size of the curvature, as the constraints according to the size of the curvature are reduced, folding as much as the curvature desired to be implemented is possible, thereby improving the freedom of design of the display substrate.

20 is a view illustrating an example in which a substrate for a display is applied according to embodiments.

Referring to FIG. 20, a display substrate according to embodiments may be applied to a display device displaying a display.

For example, the display substrate according to the embodiments may be applied to display devices such as mobile phones and tablets.

Such a display substrate may be applied to display devices such as flexible, bent or folded mobile phones and tablets.

The display substrate is applied to a display device such as a flexible, bent or folded mobile phone, a tablet, and the like, to prevent damage to a substrate due to stress in a repeatedly folded or restored display device.

Features, structures, effects, and the like described in the above-described embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, and the like exemplified in each embodiment may be combined or modified for other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

In addition, although the embodiments have been mainly described above, these are merely examples and do not limit the present invention, and those skilled in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be implemented by modification. And differences related to these modifications and applications should be construed as being included in the scope of the invention defined in the appended claims.

Claims (9)

A substrate having a long direction and a single direction, including one surface and the other surface, and including a first area and a second area; And
It includes a hole penetrating the one surface and the other surface of the substrate,
The first region is defined as a folding region that is folded such that the one-sided region faces, and the second region is defined as an unfolding region,
The hole includes a first hole formed in the first region,
The first hole is a substrate for a display including at least three first holes having different sizes in the longitudinal direction of the substrate. According to claim 1,
A display substrate including a hinge portion formed between the first region and the second region and having a hole in which an end region of the substrate is opened. According to claim 1,
The size of the outer diameter of the first hole H1 formed on the other surface is larger than the size of the outer diameter of the first hole H1 formed on the one surface. According to claim 3,
The difference between the maximum diameters of the 1-1 hole, the 1-2 hole, and the 1-3 hole is a display substrate satisfying Equation 1 below.
[Equation 1]
0.8t ≤ difference in maximum diameter of the first holes H1 ≤ 1.1t
(Where t is the thickness of the substrate) According to claim 3,
The difference between the maximum value and the minimum value of the first hole is a display substrate satisfying Equation 1 below.
[Equation 2]
0.2t ≤ difference between the maximum and minimum values of the first holes (H1)
(Where t is the thickness of the substrate) A first region having a longitudinal direction and a unidirectional direction, including one surface and the other surface, and defined as a folding area in which the one surface is folded to face each other; And a second region defined as an unfolding region; And
A first hole formed in the first region and penetrating one surface and the other surface of the substrate,
The first region includes three or more regions having different fractions of the first holes in a long direction of the substrate. A substrate having a long direction and a single direction, including one surface and the other surface, and including a first area and a second area; And
It includes a hole penetrating the one surface and the other surface of the substrate,
The first area includes a folding area and an unfolding area that are folded so that the one side faces the second area, and the second area includes an unfolding area,
The hole includes a first hole formed in the folding area of the first area,
The first hole is a substrate for a display including at least three first holes having different sizes in the longitudinal direction of the substrate. The method according to any one of claims 1, 6, and 7,
A display substrate further comprising a plurality of second holes formed in the second region. The method of claim 9,
The size or fraction of the second hole is smaller than the size or fraction of the first hole.

Images