Substrate for display

1. A substrate for display comprising:

one surface and the other surface opposite to the one surface and foldable based on a folding axis; and

wherein the substrate is defined in a first direction corresponding to the folding axis and a second direction perpendicular to the first direction,

the substrate includes:

a first region including the folding axis; and

a second region that does not include the folding axis and is located farther from the folding axis in the second direction than the first region,

a plurality of first through-holes are formed in the first region, and a plurality of second through-holes are formed in the second region,

the second through-hole includes a 2-1 opening region in which the one surface is open and a 2-2 opening region in which the other surface is open, and

the second region includes a variable region in which a size of the 2-1 opening region and a size of the 2-2 opening region of at least one of the second through-holes are different,

the size of the 2-1 opening region is larger than the size of the 2-2 opening region, and

the size of the 2-1 opening region is not more than twice the size of the 2-2 opening region.

2. The substrate for display of claim 1 , wherein the first region is disposed between the second regions, and

the variable region is 40% to 60% of the entire second region.

3. The substrate for display of claim 1 , wherein the second region includes a plurality of variable regions, and

a distance between a highest height of the variable region of the second region and the first region is 0.1 mm to 5 mm.

4. The substrate for display of claim 1 , wherein the size of the 2-1 opening region extends and changes in a direction of the first region in the variable region.

5. The substrate for display of claim 1 , wherein a curvature of the second region is greater than a curvature of the first region.

6. The substrate for display of claim 1 , wherein a surface roughness of the first region is smaller than a surface roughness of the second region.

7. The substrate for display of claim 1 , wherein the first through-hole includes a 1-1 opening region in which the one surface is open and a 1-2 opening region in which the other surface is open, and

the size of the 2-2 opening region is smaller than a size of the 1-1 opening region and a size of the 1-2 opening region.

8. A flexible display device comprising;

a substrate for display;

a display panel disposed above the substrate for display; and

a touch panel disposed on the display panel,

wherein the substrate for display includes the substrate for display according to claim 1 .

9. The flexible display device of claim 8 , wherein the substrate for display and the display panel have different sizes.

10. The flexible display device of claim 8 , wherein an area of the substrate for display is 90% or more to 110% or less of an area of the display panel.

11. A substrate for display comprising:

one surface and the other surface opposite to the one surface and foldable based on a folding axis; and

wherein the substrate is defined in a first direction corresponding to the folding axis and a second direction perpendicular to the first direction,

the substrate includes:

a first region including the folding axis; and

a second region that does not include the folding axis and is located farther from the folding axis in the second direction than the first region,

wherein the one surface is folded to face based on the folding axis,

a plurality of first through-holes are formed in the first region, and a plurality of second through-holes are formed in the second region,

the first through-hole includes a 1-1 inner region formed by opening the one surface, a 1-2 inner region formed by opening the other surface, and a first connect-hole defined as a contact point between the 1-1 inner region and the 1-2 inner region

maximum widths of the 1-1 inner region and the 1-2 inner region a greater than a width of the first connect-hole,

the second through-hole includes a 2-1 inner region formed by opening the one surface, a 2-2 inner region formed by opening the other surface, and a second connect-hole defined as a contact point between the 2-1 inner region and the 2-2 inner region,

maximum widths of the 2-1 inner region and the 2-2 inner region are greater than a width of the second connect-hole, and

a difference between the maximum width of the 1-1 inner region and the width of the first connect-hole or a difference between a maximum width of the 1-2 inner region and the width of the first connect-hole is greater than the difference between the maximum width of the 2-1 inner region and the width of the second connect-hole or the difference between the maximum width of the 2-2 inner region and the width of the second connect hole.

12. The substrate for display of claim 11 , wherein a difference between the maximum width of the 2-1 inner region and a width of the second through-hole or a difference between the maximum width of the 2-2 inner region and the width of the second through-hole is 20 μm or less.

13. The substrate for display of claim 12 , wherein the difference between the maximum width of the 1-1 inner region and the width of the first connect-hole or the difference between the maximum width of the 1-2 inner region and the width of the first connect-hole exceeds 20 μm.

14. The substrate for display of claim 11 , wherein curvature sizes of inner surfaces of the 2-1 inner region and the 2-2 inner region are smaller than curvature sizes of inner surfaces of the 1-1 inner region and the 1-2 inner region.