Flexible display panel and preparation method thereof

1. A flexible display panel, comprising:

a flexible substrate comprising a display area and a non-display area connected to each other, a thickness of the flexible substrate in the non-display area being less than a thickness of the flexible substrate in the display area, the flexible substrate comprising a first organic sub-layer, an intermediate layer, a bonding sub-layer, and a second organic sub-layer which are sequentially stacked; the first organic sub-layer, the intermediate layer, and the bonding sub-layer disposed corresponding to the display area, and the second organic sub-layer disposed corresponding to the display area and the non-display area;

a thin film transistor layer disposed on one side of the flexible substrate, and the thin film transistor layer disposed on one side of the second organic sub-layer, the thin film transistor layer comprising an array sub-layer and a wiring sub-layer; the array sub-layer disposed corresponding to the display area and the wiring sub-layer disposed corresponding to the non-display area;

an organic light-emitting layer disposed on one side of the thin film transistor layer away from the flexible substrate and disposed corresponding to the display area; and

an encapsulation layer disposed on one side of the organic light-emitting layer away from the thin film transistor layer and extending to cover the non-display area of the flexible substrate.

2. The flexible display panel according to claim 1 , wherein a thickness of the first organic sub-layer is greater than or equal to a thickness of the second organic sub-layer.

3. The flexible display panel according to claim 1 , wherein the first organic sub-layer and the second organic sub-layer are made of polyimide.

4. The flexible display panel according to claim 1 , wherein the bonding sub-layer is made of a silane coupling agent.

5. The flexible display panel according to claim 1 , wherein the intermediate layer is made of any of silicon oxide, aluminum oxide, and silicon nitride or a combination thereof.

6. A flexible display panel, comprising:

a flexible substrate comprising a display area and a non-display area connected to each other, a thickness of the flexible substrate in the non-display area being less than a thickness of the flexible substrate in the display area;

a thin film transistor layer disposed on one side of the flexible substrate, wherein the thin film transistor layer comprises an array sub-layer and a wiring sub-layer, and the array sub-layer is disposed corresponding to the display area, and the wiring sub-layer is disposed corresponding to the non-display area;

an organic light-emitting layer disposed on one side of the thin film transistor layer away from the flexible substrate and disposed corresponding to the display area; and

an encapsulation layer disposed on one side of the organic light-emitting layer away from the thin film transistor layer and extending to cover the non-display area of the flexible substrate.

7. The flexible display panel according to claim 6 , wherein the flexible substrate comprises a first organic sub-layer, an intermediate layer, a bonding sub-layer and a second organic sub-layer which are sequentially stacked, and the thin film transistor layer is disposed on one side of the second organic sub-layer; and the first organic sub-layer, the intermediate layer, and the bonding sub-layer are disposed corresponding to the display area, and the second organic sub-layer is disposed corresponding to the display area and the non-display area.

8. The flexible display panel according to claim 7 , wherein a thickness of the first organic sub-layer is greater than or equal to a thickness of the second organic sub-layer.

9. The flexible display panel according to claim 7 , wherein the first organic sub-layer and the second organic sub-layer are made of polyimide.

10. The flexible display panel according to claim 7 , wherein the bonding sub-layer is made of a silane coupling agent.

11. The flexible display panel according to claim 7 , wherein the intermediate layer is made of any of silicon oxide, aluminum oxide, and silicon nitride or a combination thereof.

12. A method of preparing a flexible display panel, comprising:

providing a carrier substrate comprising a display area and a non-display area connected to each other;

forming a first organic sub-layer, an intermediate layer, and a bonding sub-layer on the carrier substrate;

irradiating the bonding sub-layer corresponding to the non-display area to weaken an adhesion of the bonding sub-layer corresponding to the non-display area and forming a second organic sub-layer on the bonding sub-layer; and

removing the carrier substrate, and separating the second organic sub-layer corresponding to the non-display area from the first organic sub-layer, the intermediate layer, and the bonding sub-layer.

13. The method of preparing the flexible display panel according to claim 12 , wherein the step of irradiating the bonding sub-layer corresponding to the non-display area to weaken the adhesion of the bonding sub-layer corresponding to the non-display area and forming the second organic sub-layer on the bonding sub-layer, comprising:

providing a photomask comprising a light-shielding area and a light-transmission area connected to each other, an orthographic projection of the light-shielding area on the carrier substrate coincides with the display area on the carrier substrate, an orthographic projection of the light-transmission area on the carrier substrate coincides with the non-display area on the carrier substrate;

irradiating the bonding sub-layer corresponding to the non-display area with ultraviolet light by using the photomask as a mask to reduce the adhesion of the bonding sub-layer corresponding to the non-display area.

14. The method of preparing the flexible display panel according to claim 12 , wherein the step of separating the second organic sub-layer corresponding to the non-display area from the first organic sub-layer, the intermediate layer, and the bonding sub-layer, comprising:

processing the first organic sub-layer, the intermediate layer, and the bonding sub-layer corresponding to the non-display area by laser cutting to form a predetermined cutting trajectory; and

separating the second organic sub-layer corresponding to the non-display area from the first organic sub-layer, the intermediate layer, and the bonding sub-layer by mechanical stripping.

15. The method of preparing the flexible display panel according to claim 14 , wherein the predetermined cutting trajectory is from two ends of the first organic sub-layer corresponding to the non-display area to a surface of a side of the second organic sub-layer adjacent to the first organic sub-layer.