Pixel defining layer, manufacturing method therefor, and display panel

1. A pixel defining layer, comprising a first sub-defining layer, a light absorbing layer, and a second sub-defining layer which are sequentially laminated on a substrate,

wherein the light absorbing layer is configured to absorb light for exposing the first sub-defining layer, and an orthographic projection of the light absorbing layer on the substrate covers an outer edge of an orthographic projection of a surface, away from the substrate, of the first sub-defining layer on the substrate; and the orthographic projection of the light absorbing layer on the substrate comprises a plurality of rings, and each of the rings surrounds an orthographic projection of one pixel unit on the substrate.

2. The pixel defining layer according to claim 1 , wherein the outer edge of the orthographic projection of the surface, away from the substrate, of the first sub-defining layer on the substrate is inside the orthographic projection of the light absorbing layer on the substrate.

3. The pixel defining layer according to claim 1 , wherein the orthographic projection of the light absorbing layer on the substrate covers an outer edge of an orthographic projection of a surface, close to the substrate, of the second sub-defining layer on the substrate.

4. The pixel defining layer according to claim 1 , wherein a shape of at least one of an inner edge and an outer edge of the orthographic projection of the light absorbing layer on the substrate is similar to a shape of at least one of an outer edge of an orthographic projection of the first sub-defining layer on the substrate and an outer edge of an orthographic projection of the second sub-defining layer on the substrate.

5. The pixel defining layer according to claim 1 , wherein a width of the ring ranges from 1 to 5 microns.

6. The pixel defining layer according to claim 1 , wherein the orthographic projection of the light absorbing layer on the substrate covers the orthographic projection of the surface, away from the substrate, of the first sub-defining layer on the substrate.

7. The pixel defining layer according to claim 6 , wherein a shape of an outer edge of the orthographic projection of the light absorbing layer on the substrate is similar to a shape of at least one of an outer edge of an orthographic projection of the first sub-defining layer on the substrate and an outer edge of an orthographic projection of the second sub-defining layer on the substrate.

8. The pixel defining layer according to claim 1 , wherein the orthographic projection of the surface, away from the substrate, of the first sub-defining layer on the substrate is inside an orthographic projection of a surface, close to the substrate, of the first sub-defining layer on the substrate.

9. The pixel defining layer according to claim 1 , wherein an orthographic projection of a surface, away from the substrate, of the second sub-defining layer on the substrate is inside an orthographic projection of a surface, close to the substrate, of the second sub-defining layer on the substrate.

10. The pixel defining layer according to claim 1 , wherein materials of the first sub-defining layer and the second sub-defining layer are cured after being exposed and developed.

11. The pixel defining layer according to claim 1 , wherein materials of the first sub-defining layer and the second sub-defining layer are melted after being exposed and developed.

12. The pixel defining layer according to claim 1 , wherein materials of the first sub-defining layer and the second sub-defining layer are the same.

13. The pixel defining layer according to claim 1 , wherein a material of the first sub-defining layer comprises a hydrophilic material.

14. The pixel defining layer according to claim 1 , wherein a material of the second sub-defining layer comprises a hydrophobic material.

15. The pixel defining layer according to claim 1 , wherein a thickness of the first sub-defining layer ranges from 0.2 to 1 micron, and a direction of the thickness is perpendicular to a direction of a contact surface between the substrate and the first sub-defining layer; and

a thickness of the second sub-defining layer ranges from 0.5 to 3 microns.

16. The pixel defining layer according to claim 1 , wherein a material of the light absorbing layer comprises at least one of salicylate esters, benzones, benzotriazoles, substituted acrylonitriles, triazines, hindered amines, and carbon black materials.

17. The pixel defining layer according to claim 1 , wherein a material of at least one of the first sub-defining layer and the second sub-defining layer comprises at least one of polyimide, polymethyl methacrylate, fluorinated polyimide, and fluorinated polymethyl methacrylate.

18. A method for manufacturing a pixel defining layer, comprising:

forming a first material layer on a substrate;

forming a light absorbing layer on a surface of the first material layer away from the substrate, wherein the light absorbing layer is configured to absorb light exposing the first material layer;

forming a second material layer on a surface of the light absorbing layer away from the substrate; and

exposing and developing the first material layer and the second material layer to obtain the pixel defining layer, wherein the first material layer is exposed and developed to obtain a first sub-defining layer, the second material layer is exposed and developed to obtain a second sub-defining layer, and an orthographic projection of the light absorbing layer on the substrate covers an outer edge of an orthographic projection of a surface, away from the substrate, of the first sub-defining layer on the substrate; and the orthographic projection of the light absorbing layer on the substrate comprises a plurality of rings, and each of the rings surrounds an orthographic projection of one pixel unit on the substrate.

19. An organic light-emitting diode display panel, comprising the pixel defining layer according to claim 1 .

20. The organic light-emitting diode display panel according to claim 19 , wherein the outer edge of the orthographic projection of the surface, away from the substrate, of the first sub-defining layer on the substrate is inside the orthographic projection of the light absorbing layer on the substrate.