CN111179756B

CN111179756B - Composite foam, flexible OLED display panel and display device

Info

Publication number: CN111179756B
Application number: CN202010006296.3A
Authority: CN
Inventors: 曾木; 龚增超; 汪洋; 冯昱寰
Original assignee: BOE Technology Group Co Ltd; Mianyang BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Mianyang BOE Optoelectronics Technology Co Ltd
Priority date: 2020-01-03
Filing date: 2020-01-03
Publication date: 2022-07-26
Anticipated expiration: 2040-01-03
Also published as: CN111179756A

Abstract

The application discloses compound bubble is cotton, flexible OLED display panel and display device. The composite foam comprises foam and a deformable body positioned on the foam, wherein the deformable body is changed into an arc shape under the condition of bearing external force, so that in a terminal Bending (Pad Bending) process, the shape of the deformable body is changed along with the shape of a space (particularly the shape of the Bending part) enclosed by the foam and the Bending part, and the space is filled with the deformable body finally, therefore, the composite foam is firmly attached to the attaching layer, the layering phenomenon cannot occur, and the product yield of a display panel or a display device is improved. In addition, the layering between the Pad area and the composite foam can not be caused, and the product yield of the display panel or the display device is improved.

Description

Composite foam, flexible OLED display panel and display device

Technical Field

The application relates to the technical field of display, in particular to a composite foam, a flexible OLED display panel and a display device.

Background

The flexible OLED display panel is arranged in the mobile phone market through the cover plate, the abnormal shape (Liuhai) and the narrow frame, and is well commented and squinted by consumers.

Although narrow borders of the OLED display screen mobile phone are achieved by introducing a terminal Bending (Pad Bending) process, Foam (Foam) needs to be attached to a plane in a Pad Bending area and bent, so that the narrow borders and the curved surfaces of the Pad Bending side cover plate cannot be obtained at the same time, in order to pursue a more beautiful mobile phone appearance, the cover plate with the curved surfaces at four sides is scheduled, but the Pad Bending process at the curved surface is difficult, and in the Pad Bending process, a layering phenomenon can occur between the cover plate attaching layer (for example, the attaching layer can be an OLED layer according to different products) and the Foam.

Disclosure of Invention

For overcoming some or all problems that exist among the correlation technique, this application provides a compound bubble is cotton, and this bubble is cotton including the bubble and be located the last variant of bubble is cotton, and this variant becomes the arc under the condition that bears external force.

Optionally, the deformation body comprises a balloon and a gas or fluid located within the balloon; or the deformation body is soft glue.

Optionally, the gas is an inert gas.

Optionally, the surface of the air bag or the soft glue is provided with an adhesive.

Optionally, the adhesive force of the adhesive is more than or equal to 2000 gf/inch.

Optionally, the composite foam is attached to a bending portion formed by a cover plate and an attachment layer of the flexible OLED display panel, and the volume of the deformation body is not less than 80% but less than 100% of the volume of the bending portion.

Optionally, the length of the foam is greater than the width of the deformable body along the length direction of the foam.

This application on the other hand discloses a flexible OLED display panel, and this panel includes apron, Pad district, attaches in the attached layer of apron and any one kind of aforesaid compound bubble cotton, the apron with attached layer forms the flexion, compound bubble cotton include with the back that the deformation body carried on the back mutually, compound the cotton deformation body of bubble is attached in the attached layer of flexion department, the Pad district attach in the cotton back of compound bubble.

Optionally, the end of the foam opposite the deformation is flush with the edge of the Pad zone.

Another aspect of the present application discloses a display device comprising any one of the flexible OLED display panels described above.

The technical scheme provided by the embodiment of the application has at least the following beneficial effects:

1. because compound bubble is cotton including the bubble with be located the deformation on the bubble is cotton, like this, in terminal Bending (Pad binding) technology, the shape of deformation changes along with the bubble is cotton with the shape (especially the shape of flexion) of the space that the flexion encloses finally fills up the space, from this, compound bubble is cotton pastes with the attached layer, can not take place the layering phenomenon, and then, compound bubble is cotton with the apron laminating firm, compares with the scheme that only adopts the bubble cotton, guarantees the quality of complete machine and display panel equipment (for example, complete machine and display panel can not take place the interference phenomenon), improves display panel or display device's product yield. In addition, the deformation body fills the space between the bending part and the foam, so that the back surface of the foam is a plane or an arc surface with small curvature as far as possible, and after the back surface is attached to the Pad area, the Pad area and the composite foam are not layered, the quality of the assembly of the whole machine and the display panel is further ensured, and the product yield of the display panel or the display device is improved.

2. Because the gas is inert gas, the condition of oxidation reaction between parts can not be caused, and the phenomenon of water mist can not occur between the display panel or the display device, thereby improving the quality of the display panel or the display device.

3. Because the surface of gasbag or soft gluey has the binder, like this, the attached layer of the deformation body and flexion department combines firmly, ensures the filling effect of deformation body, and then, the layering phenomenon can not appear between compound bubble cotton and the flexion more. Particularly, when the adhesive force of the adhesive is not less than 2000gf/inch, the filling effect can be further secured.

4. Because the volume of the deformation body is not less than 80% of the volume of the bending portion and less than 100%, the deformation body can be fully filled in the space enclosed by the foam and the bending portion, moreover, the overflow phenomenon is not easy to occur to gas, fluid or soft rubber materials in the deformation body, and finally, the attaching effect between the composite foam and the attaching layer at the bending portion is ensured.

5. Because the length of the foam is greater than the width of the deformable body along the length direction of the foam, the arc curvature of the Pad area after the Pad Bending is reduced, the layering phenomenon does not occur between the Pad area and the composite foam, and the arc curvature of the Pad area is reduced, so that the Pad area is attached to the surface of the foam back to the deformable body as far as possible in a plane, cracks (crack) are prevented from being generated in the Pad area (particularly in the portion of the Pad area at the Bending part), and particularly, the effect can be achieved under the condition that the length of the foam is flush with the edge of the Pad area.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application.

FIG. 1 is a schematic structural diagram of a composite foam;

fig. 2 is a schematic diagram of the assembly of the composite foam with the cover plate, OLED layer and Pad region.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings in which the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be understood that the terms "first," "second," and the like, as used in the description and in the claims, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one; "plurality" means two or more. Unless otherwise indicated, "front", "rear", "lower" and/or "upper" and the like are for convenience of description and are not limited to one position or one spatial orientation. The word "comprising" or "comprises", and the like, means that the element or item listed after "comprises" or "comprising" is inclusive of the element or item listed after "comprising" or "comprises", and the equivalent thereof, and does not exclude additional elements or items.

Exemplary embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following embodiments, features of the embodiments can be supplemented with each other or combined with each other without conflict.

The inventors of the present application found that: a flexible OLED display panel comprises foam, a cover plate and an attaching layer attached to the cover plate. The attaching layer is different according to the final OLED display panel, for example, the attaching layer is an OLED layer. The cover plate and the adhesive layer are formed with a bent portion. The foam is generally rectangular and includes a front side and a back side, with the front side attached to the attachment layer at the bend. Because the flexion is that curved surface and camber are less, and the cotton surface of laminating with the flexion of bubble is the plane, like this, even if press through the pressure head of profile modeling the bubble is cotton, the bubble cotton still can't with the attached layer of flexion department pastes really, like this, causes the bubble cotton with lie in the attached layer (attached layer for example OLED layer) layering (peeling) of flexion department. In addition, in the Pad bonding process, the rectangular foam is attached to the arc-shaped bent part, so that the back surface is no longer a plane, and therefore, the Pad area cannot be attached to the back surface of the foam due to the fact that the foam cannot be attached to the bent part, and the Pad area is layered (peeling) relative to the foam after being attached; finally, because the curvature R of the curved surface of the cover plate is small, even if the foam is tightly attached to the attaching layer at the bent part, the back surface of the foam is also changed into a non-planar surface, in this case, if the Pad area is tightly attached, the Pad area is inevitably required to be forcibly bent into an arc shape close to the curvature R of the curved surface, and thus, the risk of Crack (Crack) in the Pad area is greatly increased.

Another solution is to consider the different-shaped or square Foam, but the shape of the different-shaped or profile Foam is still different from the shape of the curved part formed by the matching cover plate and the attaching layer due to differences in the processing precision of the cover plate, and therefore, it is unlikely that the Foam attaching problem can be solved only by considering the different-shaped or profile Foam.

In order to solve the problem of above-mentioned bubble cotton and attached layer layering at least, this application discloses a compound bubble is cotton. Compared with the situation that only foam is used, the composite foam shows other components besides the foam.

Referring to fig. 1 and 2, a flexible OLED display panel includes a composite foam 1, a cover plate 2, an attachment layer 3 attached to the cover plate 2, a Pad area 4, an IC chip 5, and a flexible circuit board 6 (FPC). The attaching layer 3 is attached to the cover plate 2, and the attaching layer 3 is different according to the OLED display panel, for example, the attaching layer 3 may be an OLED layer. The adhesive layer 3 and the cover plate 2 are formed with a bent portion 21. The composite foam 1 comprises a foam 11 and a deformation body 12. The foam 11 comprises a front surface 111 and a back surface 112 provided with the deformation body 12 and plays the role of a double-sided adhesive tape. Foam 11 typically, foam 11 has a rectangular shape. The Pad area 4 is a part or all of a Bonding Pad area (Bonding Pad) and is attached to the back surface 112 of the composite foam 1.

With continued reference to fig. 1 and fig. 2, the deformable body 12 is a shape-changeable component, and mainly functions to fill the space between the foam 11 and the bending portion 21, so that the bending portion 21 is attached to the foam 11. In one embodiment, the deformation 12 comprises a bladder and a gas or fluid located within the bladder. The gas is not limited in kind, and may include only one kind of gas or a mixture of gases. In the case that the airbag does not leak gas or the like, oxygen may be included in the gas, whereas oxygen is not included in the gas, because oxygen may cause oxidation reaction between components and generate water mist, thereby affecting OLED product performance, for example, rusting the device. In one embodiment, the gas is an inert gas, such as, for example, helium, argon, and the like. Based on the above embodiment, the gas may be changed into a fluid, and the fluid may also achieve the effect of deforming the airbag.

With continued reference to fig. 1 and 2, the deformable body 12 may also be a soft glue, based on the embodiment that the deformable body 12 changes its shape to fill the space between the foam 11 and the bending portion 21. The soft glue can be formed on the front surface 111 of the foam 11 by means of jet printing. In the present application, the initial shape of the deformation body 12 is not limited as long as the space between the foam 11 and the bending portion 21 is filled, but in general, the initial shape of the deformation body 12 is an arc shape because the bending portion 21 is an arc shape.

Because compound bubble is cotton including the bubble with be located the deformation on the bubble is cotton, like this, in terminal Bending (Pad binding) technology, the shape of deformation changes along with the bubble is cotton with the shape (especially the shape of flexion) of the space that the flexion encloses finally fills up the space, from this, compound bubble is cotton pastes with the attached layer of flexion department really, can not take place the layering phenomenon, and then, compound bubble is cotton with the apron laminating firm, compares with the scheme that only adopts the bubble cotton, guarantees the quality of complete machine and display panel equipment (for example, complete machine and display panel can not take place the interference phenomenon), improves display panel or display device's product yield. In addition, the deformation body fills the space between the bending part and the foam, so that the back surface of the foam is a plane or an arc surface with small curvature as far as possible, and after the back surface is attached to the Pad area, the Pad area and the composite foam are not layered, the quality of the assembly of the whole machine and the display panel is further ensured, and the product yield of the display panel or the display device is improved.

With reference to fig. 1 and fig. 2, in order to firmly combine the deformable body 12 with the attachment layer at the bending portion 21 and ensure the filling effect of the deformable body, and further, the composite foam and the attachment layer at the bending portion are not laminated, the surface of the airbag is provided with an adhesive. The kind of the adhesive is not limited as long as the adhesive can achieve the adhesive effect, and for example, the adhesive may be acrylic adhesive. Therefore, in one embodiment, the soft glue also has an adhesive on its surface. In order to ensure better bonding effect, the adhesive force of the adhesive is more than or equal to 2000 gf/inch.

Referring to fig. 1 and fig. 2, the curvature of the air bag or the soft glue is matched with the curvature of the curved portion 21, and to ensure that the curved arc can be fully filled with the air bag or the soft glue and no overflow occurs, the volume of the deformable body 12 is not less than 80% but less than 100% of the volume of the curved portion 21, for example, the volume of the deformable body 12 is 80%, 81%, 85%, 88%, 90%, 91%, 93%, 95%, 96%, 99% of the volume of the curved portion 21. The deformable body 12 is filled in the space between the foam 11 and the curved portion 21, and the volume is calculated based on the volume of the space, but since the front surface 111 of the foam 11 and the curved surface of the curved portion 21 enclose the space, the volume of the curved portion 21 can be regarded as the volume of the space.

With continued reference to fig. 1 and 2, the filling effect of the bladder or soft glue determines whether Pad zone 4 is planar or has a certain arc shape after the indenter is pressed down, and if the planar or arc shape is very small, the risk of Crack (Crack) in Pad zone 4 (especially in the portion of Pad zone corresponding to bend 21) is greatly reduced. In order to improve the attaching effect of the Pad region 4 (without delamination and/or further reduce the risk of cracks), in addition to considering the filling of the bending portion 21, the length of the foam 11 is extended on the side opposite to the deformable body 12, so that the length L of the foam 11 is extended to make the length of the foam greater than the width W of the deformable body along the length direction of the foam, that is, the length of the foam is L + W, thereby achieving a more stable effect of fixing the Pad region 4. The scheme can simultaneously correspond to COF (Chip On Flex or Chip On Film, commonly called as a Chip On Film) and COP (Chip On Panel) processes. The flat area position (i.e. the extended portion of the foam 11) just serves as the IC bonding area of the Pad area 4 (where the IC chip 5 is located). The extended length L is not limited and in one embodiment, the end 113 of the foam 11 opposite the deformation body 12 is flush with the edge of the Pad zone 4.

Another aspect of the present application discloses a display device comprising any one of the flexible OLED display panels described above. Such a display device is for example a curved screen mobile phone.

Although the present invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present invention.

Claims

1. The composite foam is applied to a flexible OLED display panel, the OLED display panel comprises a cover plate, an attachment layer and a Pad area, and a bent part is formed on the cover plate and the attachment layer; the terminal bending device is characterized by comprising foam and a deformation body located on the foam, wherein in the terminal bending process, the deformation body can be changed into an arc shape under the condition that the Pad area bears external force according to the shape between the foam and the bending part.

2. The composite foam according to claim 1, wherein the deformation body comprises an air bag and a gas or fluid located in the air bag; or the deformation body is soft glue.

3. The composite foam of claim 2, wherein the gas is an inert gas.

4. The composite foam according to claim 2, wherein the surface of the air bag or the soft glue has an adhesive.

5. The composite foam according to claim 4, wherein the adhesive has a bonding force of 2000gf/inch or more.

6. The composite foam as claimed in claim 1, wherein the composite foam is attached to a bending portion formed by the cover plate and the attachment layer of the flexible OLED display panel, and the volume of the deformation body is not less than 80% but less than 100% of the volume of the bending portion.

7. The composite foam according to claim 1, wherein the length of the foam is greater than the width of the deformable body in the length direction of the foam.

8. The utility model provides a flexible OLED display panel, its characterized in that, including apron, Pad district, attached in the attached layer of apron and the compound bubble cotton of any one of claims 1 to 7, the apron with the attached layer is formed with the flexion, compound bubble cotton include with the back that the deformation body carried on the back mutually, compound bubble cotton's deformation body attached in the attached layer of flexion department, Pad district attached in compound bubble cotton's back.

9. The flexible OLED display panel of claim 8, wherein the ends of the foam opposite the deformation are flush with the edges of the Pad region.

10. A display device comprising the flexible OLED display panel of any one of claims 8 and 9.