Flexible window substrate and flexible display device having the same

1. A flexible display device comprising:

a display panel configured to display an image;

a window substrate covering the display panel,

wherein the window substrate comprises:

a flexible base layer comprising:

a first surface facing an outside; and

a second surface facing the display panel in an opposite direction to the first surface;

a first coating layer having hardness higher than that of the base layer and comprising a plurality of first coating tiles arranged on the first surface of the base layer thereof, at a first gap from each other; and

a second coating layer having hardness higher than that of the base layer and comprising a plurality of second coating tiles arranged on a layer different from the first surface of the base layer thereof, at a second gap from each other, and

wherein the first gap of the first coating layer at least partially overlaps one of the second coating tiles of the second coating layer.

2. The flexible display device of claim 1 ,

wherein the second coating layer is on the second surface of the base layer.

3. The flexible display device of claim 1 ,

wherein the second coating layer is on a layer between the first surface and the second surface of the base layer.

4. The flexible display device of claim 1 ,

wherein the plurality of first coating tiles and the plurality of second coating tiles are isolated from each other.

5. The flexible display device of claim 1 ,

wherein the plurality of first coating tiles and the plurality of second coating tiles are each formed in a matrix form.

6. The flexible display device of claim 5 ,

wherein a crossing point of lattice type patterns which are formed by the first gap at least partially overlaps one of the second coating tiles; and

wherein a crossing point of lattice type patterns which are formed by the second gap at least partially overlaps one of the first coating tiles.

7. The flexible display device of claim 1 ,

wherein the window substrate is divided into a display area in which an image is displayed and a non-display area which surrounds the display area, and

wherein the first coating layer is at an area which corresponds to the display area.

8. The flexible display device of claim 1 ,

wherein the plurality of first coating tiles and the plurality of second coating tiles have different plane shapes from each other.

9. The flexible display device of claim 1 ,

wherein the first coating tiles each have plane areas different from those of the second coating tiles, respectively.

10. The flexible display device of claim 1 ,

wherein a thickness of the first coating tiles or the second coating tiles is between 10 μm and 100 μm.

11. The flexible display device of claim 1 ,

wherein when:

a curvature radius of a tip of a touch pen which is used by contacting a surface of the window substrate is set to be r, and

a thickness of the first coating tiles is set to be d and a maximum gap between the first coating tiles adjacent to each other is set to be S,

the maximum gap satisfies

S≤ 2√{square root over ( d (2 r−d ))}.

12. The flexible display device of claim 1 ,

wherein the gap between the first coating tiles adjacent to each other is between 20 μm and 200 μm.

13. The flexible display device of claim 1 ,

wherein the first coating tiles and the second coating tiles have a quadrangular plane shape.

14. The flexible display device of claim 13 ,

wherein the second coating tiles each correspond to the plurality of first coating tiles.

15. The flexible display device of claim 1 ,

wherein the first coating tiles have a quadrangular plane shape and the second coating tiles have a hexagonal plane shape.

16. The flexible display device of claim 15 ,

wherein the second coating tiles are arranged so that respective corners of three of the hexagonal coating tiles are adjacent to a point.

17. The flexible display device of claim 16 ,

wherein a crossing point of lattice type patterns which are formed by the first gap at least partially overlaps one of the second coating tiles, and

wherein at least some of the crossing points formed by the second gap overlap one of the first coating tiles.

18. The flexible display device of claim 1 ,

wherein the base layer comprises a material selected from the group consisting of elastomer, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polymethyl methacrylate (PMMA), silicone, polyurethane (PU), and combinations thereof.

19. The flexible display device of claim 1 ,

wherein the first coating tiles or the second coating tiles comprises a material selected from the group consisting of epoxy, acryl, silicone, polyurethane (PU), graphene, carbon nanotube (CNT), indium tin oxide (ITO), indium zinc oxide (IZO), Si, SiOx, SiNx, and combinations thereof.

20. The flexible display device of claim 1 , wherein the flexible display device senses a touch from an outside.

21. A flexible display device comprising:

a display panel configured to display an image; and

a window substrate covering the display panel,

wherein the window substrate comprises:

a flexible base layer comprising:

a first surface facing an outside; and

a second surface facing the display panel in an opposite direction to the first surface;

a first coating layer having hardness higher than that of the base layer and comprising a plurality of first coating tiles arranged on the first surface of the base layer thereof, at a first gap from each other;

a second coating layer having hardness higher than that of the base layer and comprising a plurality of second coating tiles arranged on a layer different from the first surface of the base layer thereof, at a second gap from each other; and

a third coating layer between the first surface and the second surface of the base layer,

wherein the second coating layer is on the second surface of the base layer, and

wherein the first gap of the first coating layer at least partially overlaps one of the second coating tiles of the second coating layer.

22. The flexible display device of claim 21 ,

wherein the third coating layer comprises a plurality of third coating tiles which are arranged at a third gap from each other.

23. The flexible display device of claim 22 ,

wherein the third gap of the third coating layer at least partially overlaps one of the first coating tiles of the first coating layer or one of the second coating tiles of the second coating layer.

24. The flexible display device of claim 21 ,

wherein the third coating layer is of a single body which is formed as one layer.

25. The flexible display device of claim 21 , wherein the flexible display device senses a touch from an outside.

26. A flexible window substrata comprising:

a flexible base layer comprising:

a first surface facing an outside; and

a second surface facing a display panel in an opposite direction to the first surface;

a first coating layer having hardness higher than that of the base layer and comprising a plurality of first coating tiles arranged on the first surface of the base layer thereof, at a first gap from each other; and

a second coating layer having hardness higher than that of the base layer and comprising a plurality of second coating tiles arranged on a layer different from the first surface of the base layer thereof, at a second gap from each other,

wherein the first gap of the first coating layer at least partially overlaps one of the second coating tiles of the second coating layer,

wherein the plurality of first coating tiles are electrically isolated from each other, and

wherein the plurality of second coating tiles are electrically isolated from each other.

27. The flexible window substrate of claim 26 ,

wherein the second coating layer is on the second surface of the base layer.

28. The flexible window substrate of claim 27 , further comprising:

a third coating layer on a layer between the first surface and the second surface of the base layer.

29. The flexible window substrate of claim 28 ,

wherein the third coating layer comprises a plurality of third coating tiles which are arranged at a third gap from each other.

30. The flexible window substrate of claim 29 ,

wherein the third gap of the third coating layer at least partially overlaps one of the first coating tiles of the first coating layer or one of the second coating tiles of the second coating layer.

31. The flexible window substrate of claim 26 ,

wherein the second coating layer is between the first surface and the second surface of the base layer.

32. The flexible window substrate of claim 26 ,

wherein the plurality of first coating tiles and the plurality of second coating tiles are each in a matrix form.

33. The flexible window substrate of claim 32 ,

wherein a crossing point of lattice type patterns which are by the first gap at least partially overlaps one of the second coating tiles; and

wherein a crossing point of lattice type patterns which are by the second gap at least partially overlaps one of the first coating tiles.

34. The flexible window substrate of claim 26 ,

wherein the plurality of first coating tiles and the plurality of second coating tiles have different plane shapes from each other.

35. The flexible window substrate of claim 26 ,

wherein the base layer comprises a material selected from the group consisting of elastomer, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polymethyl methacrylate (PMMA), silicone, polyurethane (PU), and combinations thereof.

36. The flexible window substrate of claim 26 ,

wherein the first coating tiles or the second coating tiles comprises a material selected from the group consisting of epoxy, acryl, silicone, polyurethane (PU), graphene, carbon nanotube (CNT), indium tin oxide (ITO), indium zinc oxide (IZO), Si, SiOx, SiNx, and combinations thereof.