Display substrate for avoiding breaks and preparation method thereof, bonding method of display panel and display apparatus

1. A display substrate, comprising a display region and a bezel region, wherein the display region comprises a plurality of corner regions, and at least one of the plurality of corner regions comprises a corner display region and a blank corner cutting region which are alternately disposed;

the corner display region comprises a composite wiring layer disposed on a base substrate, a drive structure layer disposed on the composite wiring layer and a light-emitting element disposed on the drive structure layer; the composite wiring layer comprises a first wiring layer, a second wiring layer and a first insulating layer disposed between the first wiring layer and the second wiring layer; the drive structure layer comprises a pixel drive circuit and a plurality of connection electrodes; and

the first wiring layer comprises a gate line, and the second wiring layer comprises a data line, wherein the gate line, the data line and the light-emitting element are connected to the pixel drive circuit through the plurality of connection electrodes.

2. The display substrate according to claim 1 , wherein the pixel drive circuit comprises a first transistor, the plurality of connection electrodes comprise a first connection electrode, a second connection electrode and a fourth connection electrode, the light-emitting element comprises an anode, a cathode and an organic light-emitting layer disposed between the anode and the cathode; and

the first connection electrode is connected to the gate line and a gate electrode of the first transistor, the second connection electrode is connected to the data line and a source electrode of the first transistor, and the fourth connection electrode is connected the anode and a drain electrode of the first transistor.

3. The display substrate according to claim 2 , wherein the bezel region comprises a power supply line, a third connection electrode, and a fifth connection electrode,

wherein the power supply line is disposed on the first wiring layer or the second wiring layer, the third connection electrode is disposed in a same layer as the source electrode and the drain electrode of the first transistor, and the fifth connection electrode and the anode are disposed in a same layer; and

the third connection electrode is connected to the power supply line and the fifth connection electrode, and the fifth connection electrode is connected to the third connection electrode and the cathode.

4. The display substrate according to claim 1 , wherein the base substrate comprises a first flexible material layer and a first barrier layer disposed on the first flexible material layer, and the composite wiring layer is disposed on the first barrier layer.

5. The display substrate according to claim 1 , wherein the base substrate comprises a first flexible material layer, a first barrier layer disposed on the first flexible material layer, a second insulating layer, and a second flexible material layer disposed on the second insulating layer, and the composite wiring layer is disposed between the first barrier layer and the second insulating layer.

6. The display substrate according to claim 1 , wherein an edge of the blank corner cutting region facing the bezel region is a first arc, and an edge of the corner display region facing the bezel region is a second arc, wherein the first arc and the second arc are located on a circle with a same center and a same radius.

7. The display substrate according to claim 6 , wherein an arc length of the first arc is 18 to 35 microns and an arc length of the second arc is 180 to 250 microns.

8. A display apparatus, comprising the display substrate according to claim 1 .

9. A method for preparing a display substrate, wherein the display substrate comprises a display region and a bezel region, the display region comprises a plurality of corner regions, and at least one of the plurality of corner regions comprises a corner display region and a blank corner cutting region which are alternately disposed, the preparation method comprises:

forming a composite wiring layer on a base substrate, wherein the composite wiring layer of the corner display region comprises a first wiring layer, a second wiring layer and a first insulating layer disposed between the first wiring layer and the second wiring layer, wherein the first wiring layer comprises a gate line and the second wiring layer comprises a data line;

forming a drive structure layer on the composite wiring layer, wherein the drive structure layer of the corner display region comprises a pixel drive circuit and a plurality of connection electrodes;

forming a light-emitting element on the drive structure layer, removing all film layer structures in the blank corner cutting region, wherein the gate line, the data line, and the light-emitting element are connected to the pixel drive circuit through the plurality of connection electrodes.

10. The preparation method according to claim 9 , wherein, the pixel drive circuit comprises a first transistor, the plurality of connection electrodes comprise a first connection electrode, a second connection electrode and a fourth connection electrode, the light-emitting element comprises an anode, a cathode and an organic light-emitting layer disposed between the anode and the cathode, and the bezel region comprises a power supply line, a third connection electrode and a fifth connection electrode;

the drive structure layer comprises a second insulating layer disposed on the composite wiring layer, an active layer disposed on the second insulating layer, a third insulating layer covering the active layer, a first gate metal layer disposed on the third insulating layer, a fourth insulating layer covering the first gate metal layer, a second gate metal layer disposed on the fourth insulating layer, a fifth insulating layer covering the second gate metal layer, a first source and drain metal layer disposed on the fifth insulating layer, a passivation layer disposed on the first source and drain metal layer, a first planarization layer disposed on the passivation layer, a metal conductive layer on the planarization layer, and a second planarization layer disposed on the metal conductive layer;

wherein the power supply line is disposed on the first wiring layer or the second wiring layer;

the first connection electrode is disposed on the second gate metal layer and is connected to the gate line and a gate electrode of the first transistor;

the second connection electrode and the third connection electrode are disposed on the first source and drain metal layer, the second connection electrode is connected to the data line and a source electrode of the first transistor, and the third connection electrode is connected to the power supply line and the fifth connection electrode;

the fourth connection electrode is disposed on the metal conductive layer and is connected to the anode and a drain electrode of the first transistor; and

the fifth connection electrode is disposed in a same layer as the anode, and is connected to the third connection electrode and the cathode.

11. A method for bonding a display panel, wherein the display panel comprises a display region and a bezel region, the display region comprises a plurality of corner regions, and at least one of the plurality of corner regions comprises a corner display region and a blank corner cutting region which are alternately disposed; and the bonding method comprises:

forming an optical adhesive layer on a side of the display panel facing a cover plate, wherein the optical adhesive layer comprises a plurality of first fan-shaped regions and first opening regions which are alternately disposed; an orthographic projection of the corner display region on the display panel comprises an orthographic projection of the first fan-shaped regions on the display panel, and an orthographic projection of the first opening regions on the display panel comprises an orthographic projection of the blank corner cutting region on the display panel;

bonding a back film on a side of the display panel away from the cover plate;

pulling the display panel through a carrier film for copying; and

bonding the display panel to the cover plate, and removing the carrier film.

12. The bonding method according to claim 11 ,

wherein the back film comprises a plurality of second fan-shaped regions and second opening regions which are alternately disposed; an orthographic projection of the corner display region on the display panel comprises an orthographic projection of the second fan-shaped regions on the display panel, and an orthographic projection of the second opening regions on the display panel comprises the orthographic projection of the blank corner cutting region on the display panel; and

the carrier film comprises a plurality of third fan-shaped regions and third opening regions which are alternately disposed; an orthographic projection of the corner display region on the display panel comprises an orthographic projection of the third fan-shaped regions on the display panel, and an orthographic projection of the third opening regions on the display panel comprises the orthographic projection of the blank corner cutting region on the display panel.

13. The bonding method according to claim 12 , wherein an edge of the corner display region facing the bezel region is a second arc;

an edge of a first fan-shaped region facing the bezel region is a third arc, and an arc length of the third arc is smaller than the arc length of the second arc by 20 microns to 50 microns;

an edge of a second fan-shaped region facing the bezel region is a fourth arc, and an arc length of the fourth arc is smaller than the arc length of the second arc by 20 microns to 50 microns; and

an edge of a third fan-shaped region facing the bezel region is a fifth arc, and an arc length of the fifth arc is smaller than the arc length of the second arc by 20 microns to 50 microns.

14. The bonding method according to claim 11 ,

wherein the back film comprises a fourth opening region, and an orthographic projection of the fourth opening region on the display panel comprises the orthographic projection of the corner region on the display panel; and

the carrier film comprises a fifth opening region, and an orthographic projection of the fifth opening region on the display panel comprises the orthographic projection of the corner region on the display panel.