CN109817687B

CN109817687B - Flexible substrate and OLED display panel

Info

Publication number: CN109817687B
Application number: CN201910118131.2A
Authority: CN
Inventors: 班圣光
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2019-02-15
Filing date: 2019-02-15
Publication date: 2021-10-08
Anticipated expiration: 2039-02-15
Also published as: CN109817687A

Abstract

The invention relates to the field of display technology, and discloses a flexible substrate and an OLED display panel, wherein the flexible substrate comprises: a plurality of island regions arranged in an array; bridge components are distributed between adjacent island regions and connect the adjacent island regions ; wherein, the bridge assembly between two adjacent island regions includes at least one sacrificial bridge and at least one functional bridge with signal traces, and the Young's modulus of the sacrificial bridge is greater than the Young's modulus of the functional bridge quantity. In the above-mentioned flexible substrate, a sacrificial bridge with a large Young's modulus is arranged corresponding to the functional bridge, which can share most of the tensile load of the functional bridge and is beneficial to prevent cracks on the inner arc surface of the functional bridge.

Description

Flexible substrate and OLED display panel

Technical Field

The invention relates to the technical field of display, in particular to a flexible substrate and an OLED display panel.

Background

In recent years, the Organic Light-Emitting Diode (OLED) display technology is gradually replacing the liquid crystal display technology, and the OLED display technology has the characteristics of flexibility, high contrast, good color reduction and the like.

The main method for realizing the flexibility of the OLED panel is to form an array-distributed island region and a functional bridge for signal routing by opening a hole in a PI Polyimide film (Polyimide substrate), where the functional bridge is mostly an arc-shaped structure, and the arc-shaped functional bridge is easily subjected to a tensile stress on its inner arc surface to cause a crack 3 (see fig. 1).

Disclosure of Invention

The invention discloses a flexible substrate and an OLED display panel, which are used for preventing a functional bridge between adjacent island regions from cracking due to tensile stress.

In order to achieve the purpose, the invention provides the following technical scheme:

a flexible substrate, comprising:

a plurality of island regions arranged in an array;

the bridge components are distributed between the adjacent island regions and are connected with the adjacent island regions;

the bridge assembly between two adjacent island regions comprises at least one sacrificial bridge and at least one functional bridge with signal routing, and the Young modulus of the sacrificial bridge is larger than that of the functional bridge.

When the flexible substrate is stretched, the Young modulus of the sacrificial bridge is larger than that of the functional bridge, so that most of tensile stress is borne by the sacrificial bridge in one bridge assembly, and compared with the situation that only the functional bridge is used, the tensile load borne by the functional bridge is reduced, the tensile stress borne by the inner arc-shaped surface of the functional bridge is also obviously reduced, and cracks are not easy to appear on the inner arc-shaped surface of the functional bridge.

Preferably, the width of the sacrificial bridge is greater than the width of the corresponding functional bridge.

Preferably, the sacrificial bridge and the functional bridge are both arc-shaped, and the bending radius of the sacrificial bridge is larger than that of the corresponding functional bridge.

Preferably, the sacrificial bridge and the functional bridge are both arc-shaped, and the opening of the sacrificial bridge faces in the opposite direction to the opening of the functional bridge in the same bridge assembly.

Preferably, the openings of the sacrificial bridge are arranged opposite to the openings of the corresponding functional bridges.

Preferably, the opening of the sacrificial bridge is oriented in the same direction as the opening of the functional bridge in the same bridge assembly.

Preferably, the functional bridge comprises:

the insulating layer is in contact with the signal wire;

and the reinforced metal layer is positioned on one side of the insulating layer, which is far away from the signal wiring.

Preferably, a reinforcing metal strip is arranged along the intrados of the functional bridge.

Preferably, the reinforcing metal strip and the signal trace are arranged in the same layer.

The invention also provides the following technical scheme:

an OLED display panel comprising: the flexible substrate of the technical scheme. The advantages of the OLED display panel and the flexible substrate are the same as those of the prior art, and are not described herein again.

The advantages of the OLED display panel and the flexible substrate are the same as those of the prior art, and are not described herein again.

Drawings

FIG. 1 is a schematic structural diagram of a functional bridge of a flexible substrate in the prior art;

fig. 2 is a schematic structural diagram of a flexible substrate provided in an embodiment of the present invention when the opening directions of the functional bridge and the sacrificial bridge are opposite;

fig. 3 is a schematic structural diagram of a flexible substrate provided in an embodiment of the present invention when the opening directions of the functional bridge and the sacrificial bridge are the same;

fig. 4 is a schematic structural diagram of a functional bridge in a flexible substrate according to an embodiment of the present invention;

fig. 5 is a cross-sectional view of a functional bridge in a flexible substrate according to an embodiment of the invention.

Icon: 1-a non-metallic layer; 2-signal routing; 3-cracking; 4-reinforcing metal strips; 5-an island region; 6-sacrificial bridge; 7-functional bridge; 8-PI substrate; 9-Barrier layer; 10-reinforcing a metal layer; 11-GI1 layer; layer 12-Data Line 1; 13-PVX1 layer; 14-Data Line2 layer; 15-PVX2 layer; 16-PVX3 layer.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

The flexible substrate provided by the embodiment of the invention comprises:

a plurality of island regions 5 arranged in an array;

bridge elements distributed between the adjacent island regions 5 and connecting the adjacent island regions 5;

wherein, the bridge component between two adjacent island regions 5 comprises at least one sacrificial bridge 6 and at least one arc-shaped functional bridge 7 with the signal trace 2, and the Young modulus of the sacrificial bridge 6 is larger than that of the functional bridge 7.

The signal trace 2 may be a gate line, a data line, a TP (touch control) signal line, and the like.

When the flexible substrate is stretched, the young modulus of the sacrificial bridge 6 is greater than that of the functional bridge 7, so that most of the tensile stress borne by the sacrificial bridge 6 in one bridge assembly is reduced compared with that borne by the functional bridge 7, the tensile load borne by the functional bridge 7 is reduced, the tensile stress borne by the inner arc-shaped surface of the functional bridge 7 is also obviously reduced, and the crack 3 is not easy to appear on the inner arc-shaped surface of the functional bridge 7.

In order to obtain a larger young's modulus, the relevant parameters of the sacrificial bridge 6 and the functional bridge 7 can be adjusted as follows:

alternatively, as shown in fig. 2 and 3, the width of the sacrificial bridge 6 is greater than that of the corresponding functional bridge 7, and the greater the width of the sacrificial bridge 6, the stronger it is against deformation; here, the width of the sacrificial bridge 6 being greater than the width of the corresponding functional bridge 7 means: the width of the sacrificial bridge 6 is greater than the width of the functional bridge 7 in the same bridge assembly.

Optionally, as shown in fig. 2 and fig. 3, the sacrificial bridge 6 and the functional bridge 7 are both arc-shaped, and the bending radius of the sacrificial bridge 6 is greater than the bending radius of the corresponding functional bridge 7, so that the functional bridge 7 can always deform in the range of the linear deformation region without nonlinear deformation, and thus the functional bridge 7 can be well protected.

When the sacrificial bridge 6 and the functional bridge 7 are both arc-shaped, the opening direction of the sacrificial bridge 6 and the opening direction of the functional bridge 7 in the same bridge component may be the same or opposite.

As shown in fig. 3, in the same bridge assembly, the opening of the sacrificial bridge 6 is oriented in the same direction as the opening of the functional bridge 7, and the functional bridge 7 is located on the outer arc side of the sacrificial bridge 6.

When the opening of the sacrificial bridge 6 is oriented opposite to the opening of the functional bridge 7, there may be at least two cases:

first, as shown in fig. 2, the openings of the sacrificial bridges 6 are opposite to the openings of the corresponding functional bridges 7, so that the sacrificial bridges 6 and the corresponding functional bridges 7 form a closed structure, which is more beneficial to the stability of the sacrificial bridges 6 and the functional bridges 7.

Secondly, the openings of the sacrificial bridges 6 are arranged opposite to the openings of the corresponding functional bridges 7.

In addition, the functional bridge 7 includes an insulating layer in contact with the signal trace 2;

and the reinforced metal layer 10 is positioned on one side of the insulating layer, which is far away from the signal trace 2.

For example, the functional bridge 7 includes a PI (Polyimide) substrate 8 and a plurality of film layers stacked on the PI substrate 8, but the film layer having the signal trace 2 has the following structure: as shown in fig. 4, that is, metal signal traces 2 and non-metal layers 1 extending along the arc length direction of the functional bridge 7 are distributed at intervals from the inner arc side to the outer arc side of the functional bridge 7, so that the extending direction from the inner arc side to the outer arc side is caused, the young modulus of the functional bridge 7 is not uniform, and in order to obtain the uniform young modulus from the inner arc side to the outer arc side, a reinforcing metal layer 10 is arranged on one side of the insulating layer away from the film layer having the signal traces 2, the reinforcing metal layer 10 has better toughness, and the young modulus of the functional bridge 7 from the inner arc side to the outer arc side tends to be uniform, so that the deformation of the functional bridge 7 from the inner arc side to the outer arc side tends to be uniform, cracks 3 are not easily generated on the inner side of the functional bridge 7, and the insulating layer therein can avoid the signal traces 2 and the reinforcing metal layer 10;

in particular, the structure of the functional bridge 7 includes, but is not limited to, the following forms: referring to fig. 5, a PI substrate 8, a Barrier layer 9, a reinforcing metal layer 10, a GI1 layer 11, a Data Line1 layer 12, a PVX1 layer 13, a Data Line2 layer 14, a PVX2 layer 15, a reinforcing metal layer 10, and a PVX3 layer 16 are sequentially from bottom to top;

the Data Line1 layer 12 and the Data Line2 layer 14 are both film layers having the signal trace 2, that is, in such film layers, metal signal traces 2 and nonmetal layers 1 extending along the arc length direction of the functional bridge 7 are distributed at intervals from the inner arc side to the outer arc side of the functional bridge 7.

The reinforced metal layer 10 is a laminated structure composed of one or more of Mo, Ti, Al and Cu, and has a thickness in the range of

For example, can be

And

wherein, the thickness of the PI substrate 8 is 5um-15um, for example, 5um, 7um, 10um, 12um and 15 um;

barrier layer 9 is a buffer layer having a thickness of

For example, can be

And

barrier layer 9 is composed of SiNx and SiO₂Or a layer structure thereof;

the structure of the GI1 layer 11 is SiNx and SiO₂Or one of the layers of the laminated structure of (1) and the thickness of

It may be for example that,

and

the structures of the PVX1 layer 13, the PVX2 layer 15 and the PVX3 layer 16 are SiNx and SiO₂Or one of the layers of the laminated structure of (1) and the thickness of

For example, can be

And

the GI1 layer 11 and the PVX2 layer 15 are the insulating layers contacting the signal traces 2, the GI1 layer 11 is used to prevent the reinforcing metal layer 10 from directly contacting the Data Line1 layer 12 on the lower side of the reinforcing metal layer, which causes short circuit of different signal traces 2 in the Data Line1 layer 12, and the PVX2 layer 15 is used to prevent the Data Line2 layer 14 from directly contacting the reinforcing metal layer 10 on the upper side of the reinforcing metal layer, which causes short circuit of different signal traces 2 in the Data Line2 layer 14.

Preferably, as shown in fig. 4, the reinforcing metal strips 4 are arranged along the intrados of the functional bridge 7, so that the reinforcing metal strips 4 with better toughness can make the young's modulus between each layer of film layers tend to be uniform, thereby preventing the intrados of each layer of film layers of the functional bridge 7 from cracking.

The reinforcing metal strip 4 can cover a plurality of films of the intrados of the functional bridge 7, and can also be arranged on the same layer with the film with the signal wiring 2.

When the reinforcing metal strip 4 and the film layer with the signal wiring 2 are arranged on the same layer, the reinforcing metal strip 4 is conveniently manufactured when the signal wiring 2 is manufactured by utilizing the photoetching technology, and the processing procedure is favorably saved.

Example two

The OLED display panel provided by the embodiment of the invention comprises: the flexible substrate as provided in the first embodiment.

When the OLED display panel is stretched, the sacrificial bridge 6 in the flexible substrate shares part of the tensile load of the functional bridge 7, and compared with the situation that only the functional bridge 7 is arranged, the tensile load borne by the functional bridge 7 is reduced, so that the tensile stress borne by the inner arc-shaped surface of the functional bridge 7 is also obviously reduced, and the crack 3 is not easy to appear on the inner arc-shaped surface of the functional bridge 7.

It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A flexible substrate, characterized in that, comprising:

Island areas arranged in multiple arrays;

Bridge components are distributed between adjacent island areas and connect adjacent island areas;

Wherein, the bridge assembly between two adjacent island regions includes at least one sacrificial bridge and at least one functional bridge with signal wiring, the sacrificial bridge and the functional bridge are connected in parallel with each other, and the sacrificial bridge is connected in parallel with each other. The Young's modulus is greater than the Young's modulus of the functional bridge.

2 . The flexible substrate according to claim 1 , wherein the width of the sacrificial bridge is greater than that of the corresponding functional bridge. 3 .

3 . The flexible substrate according to claim 1 , wherein both the sacrificial bridge and the functional bridge are arc-shaped, and the bending radius of the sacrificial bridge is larger than that of the corresponding functional bridge. 4 .

4 . The flexible substrate according to claim 1 , wherein the sacrificial bridge and the functional bridge are both arc-shaped, and in the same bridge assembly, the opening of the sacrificial bridge is oriented in the same direction as the functional bridge. 5 . The openings of the bridges face in the opposite direction.

5 . The flexible substrate according to claim 4 , wherein the openings of the sacrificial bridges are disposed opposite to the corresponding openings of the functional bridges. 6 .

6 . The flexible substrate according to claim 1 , wherein the sacrificial bridge and the functional bridge are both arc-shaped, and in the same bridge assembly, the opening of the sacrificial bridge is oriented in the same direction as the functional bridge. 7 . The openings of the bridge face the same direction.

7. The flexible substrate of claim 1, wherein the functional bridge comprises:

an insulating layer in contact with the signal wiring, the insulating layer and the signal wiring are arranged along the thickness direction of the flexible substrate;

A reinforced metal layer on the side of the insulating layer away from the signal trace.

8 . The flexible substrate according to claim 1 , wherein a reinforcing metal strip is provided along the inner arc surface of the functional bridge. 9 .

9 . The flexible substrate according to claim 8 , wherein the reinforcing metal strips are arranged on the same layer as the signal traces. 10 .

10. An OLED display panel, comprising: the flexible substrate according to any one of claims 1-9.