Flexible substrate and manufacturing method thereof, and display device

1. A flexible substrate, comprising a display region and a bending region outside the display region, wherein the flexible substrate comprises a base substrate and a first organic layer and a second organic layer which are sequentially laminated on the base substrate;

the flexible substrate is a display substrate and comprises a pixel array in the display region and on the base substrate, and the first organic layer comprises a pixel defining layer and a spacer layer on a side of the pixel defining layer away from the base substrate;

the spacer layer comprises a plurality of first portions spaced apart from each other to form a concave-convex structure in the bending region, and the concave-convex structure is at a surface of the first organic layer where the first organic layer contacts the second organic layer.

2. The flexible substrate according to claim 1 , wherein the concave-convex structure comprises at least one concave structure, and

the second organic layer comprises a first portion filled into the at least one concave structure and a second portion outside the at least one concave structure.

3. The flexible substrate according to claim 2 , wherein the concave-convex structure has a higher distribution density, a larger planar area, or a larger cross section area at a position corresponding to an edge of the second organic layer than at a position corresponding to a center of the second organic layer.

4. The flexible substrate according to claim 2 , wherein the concave-convex structure comprises a plurality of concave structures;

the plurality of concave structures are arranged in a plurality of rows, and an extension direction of each of the plurality of rows is parallel to a bending axis of the bending region.

5. The flexible substrate according to claim 4 , wherein a planar shape of each of the plurality of concave structures is a strip, an extension direction of the strip is parallel to the bending axis, and a width of the strip gradually decreases from a position corresponding to an edge of the second organic layer to a position corresponding to a center of the second organic layer.

6. The flexible substrate according to claim 2 , wherein the concave-convex structure comprises a plurality of concave structures, each of the plurality of concave structures is strip-shaped, and the plurality of concave structures are intersected to form a mesh structure.

7. The flexible substrate according to claim 2 , wherein a cross-sectional shape of the concave structure in a direction perpendicular to the base substrate comprises at least one selected from the group consisting of a rectangle, a trapezoid, a semicircle and an oval;

a planar shape of the concave structure in a direction parallel to the base substrate comprises at least one selected from the group consisting of a circle, a triangle, a rectangle, an oval, a T-shape, a strip shape, a polyline shape and a mesh shape.

8. The flexible substrate according to claim 1 , wherein the flexible substrate further comprises an insulating layer between the base substrate and the first organic layer, and the insulating layer comprises an opening in the bending region for bending, and the first organic layer is covered on the insulating layer and filled in the opening.

9. The flexible substrate according to claim 1 , wherein the second organic layer is extended outside the bending region, and the concave-convex structure is further provided at a surface of the first organic layer where the first organic layer contacts the second organic layer outside the bending region.

10. The flexible substrate according to claim 1 , wherein pixel defining layer comprises a plurality of second portions spaced apart from each other and the plurality of first portions are respectively on the plurality of second portions in one-to-one correspondence, thereby the concave-convex structure being formed by both the pixel defining layer and the spacer layer.

11. The flexible substrate according to claim 10 , further comprising a planarization layer on a side of the pixel defining layer close to the base substrate,

wherein the pixel array comprises a pixel electrode layer between the planarization layer and the pixel defining layer in the display region.

12. The flexible substrate according to claim 11 , wherein the second organic layer is filled into a concave region of the concave-convex structure of the first organic layer, and is in contact with a surface of the planarization layer.

13. The flexible substrate according to claim 1 , wherein the second organic layer is a UV-curable material.

14. The flexible substrate according to claim 1 , wherein a material of the first organic layer is at least one selected from the group consisting of polymethyl methacrylate, polycarbonate, polystyrene, epoxy resin, polyimide and polyethylene.

15. The flexible substrate according to claim 1 , further comprising a bonding region outside the display region,

wherein the bending region is between the display region and the bonding region.

16. A display device, comprising the flexible substrate according to claim 1 .

17. A manufacturing method of the flexible substrate according to claim 1 , comprising:

forming the first organic layer on the base substrate, and processing the surface of the first organic layer in the bending region to form the concave-convex structure, and

forming the second organic layer in the bending region.

18. The manufacturing method according to claim 17 , wherein the forming the second organic layer comprises:

forming an organic solution layer on the first organic layer, and curing the organic solution layer to form the second organic layer.

19. The flexible substrate according to claim 1 , wherein the spacer layer further comprises a plurality of spacers spaced apart from each other in the display region to space apart adjacent pixels of the pixel array.

20. The flexible substrate according to claim 1 , wherein the concave-convex structure comprises a plurality of concave structures;

each of the plurality of concave structures is arranged in a strip extended along a bending axis of the bending region;

a width of the strip gradually increases from a center of the bending region to an edge of the bending region.