CN112086581B

CN112086581B - Display panel, preparation method thereof and display device

Info

Publication number: CN112086581B
Application number: CN202011065893.XA
Authority: CN
Inventors: 董晴晴; 康梦华; 冯丹丹; 兰兰; 邱少亚; 姜博
Original assignee: Kunshan New Flat Panel Display Technology Center Co Ltd
Current assignee: Kunshan New Flat Panel Display Technology Center Co Ltd
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2022-09-13
Anticipated expiration: 2040-09-30
Also published as: CN112086581A

Abstract

The display panel comprises a device layer and a blocking layer which are arranged in a stacked mode, wherein the device layer comprises a plurality of light emitting units, the blocking layer comprises a plurality of blocking sub-units, a gap is reserved between every two adjacent blocking sub-units, and the light emitting units are covered by orthographic projections of the blocking sub-units on the device layer. This application has set up the barrier layer of patterning through the one side on device layer, has reached display panel when curling and buckling, and the transmission is piled up to the unable persistence of the stress on barrier layer, can alleviate the stress on barrier layer, can effectively avoid the emergence of the phenomenon of droing, can effectively improve display panel's life.

Description

Display panel, preparation method thereof and display device

Technical Field

The invention relates to the technical field of display, in particular to a display panel, a preparation method thereof and a display device.

Background

Flexible Organic Light-Emitting diodes (OLEDs) are receiving more and more attention due to their unique advantages of self-luminescence, high color purity, flexibility and curling. However, in recent years, the flexible OLED display panel is easily wrinkled, cracked or peeled off (peeling) during the bending or folding process, which seriously reduces the lifetime of the OLED display panel.

The reason is mainly because the flexible OLED display panel product in the prior art is easy to fall off at the Barrier layer (Barrier layer) when being bent.

Disclosure of Invention

In view of this, embodiments of the present invention provide a display panel, a method for manufacturing the same, and a display device, so as to solve the problem that a barrier layer in the prior art is easy to fall off and separate.

An embodiment of the present invention provides a display panel, including:

a device layer including a plurality of light emitting cells; and the number of the first and second groups,

the barrier layer is positioned on one side of the light-emitting surface of the device layer and comprises a plurality of barrier subunits, and a gap is formed between every two adjacent barrier subunits;

wherein an orthographic projection of the blocking sub-unit on the device layer covers the light emitting unit.

In one embodiment, an area of an orthographic projection of the blocking subunit on the device layer is 1.0-1.5 times an area of the light emitting unit;

preferably, the area of the orthographic projection of the blocking sub-unit on the device layer is 1.1-1.2 times the area of the light-emitting unit. Through the arrangement mode, the blocking subunit can completely cover the light-emitting unit, and the optical performance of the display panel can be effectively ensured.

In one embodiment, a light blocking unit is arranged in the gap between two adjacent blocking subunits. By the arrangement mode, the phenomenon of optical crosstalk between adjacent light-emitting units is avoided, and the display effect is improved.

In one embodiment, the light blocking unit has the same thickness as the blocking subunit. By the arrangement mode, the phenomenon that the water and oxygen blocking capability of the packaging layer is reduced due to obvious steps in the subsequent preparation of the packaging layer is avoided.

In one embodiment, an orthogonal projection of the light blocking unit between two adjacent blocking subunits on the device layer includes a polygon, a triangle, a circle, an ellipse or an irregular figure. By the arrangement mode, the stress accumulated on the barrier layer when the display panel is bent can be further released.

In one embodiment, the material of the light blocking unit includes a cyclized rubber-based negative photoresist or a black glue. These two materials are very common light blocking materials and have excellent light blocking properties.

In one embodiment, the light emitting unit includes at least two adjacent sub-pixel units. The present embodiment provides an implementable manner of a light emitting unit.

In one embodiment, the at least two adjacent sub-pixel units include at least two adjacent red sub-pixel units, at least two adjacent green sub-pixel units, at least two adjacent blue sub-pixel units, at least two adjacent red and green sub-pixel units, at least two adjacent red and blue sub-pixel units, or at least two adjacent blue and green sub-pixel units. The present embodiment provides for the implementation of a wide variety of sub-pixel cells.

The embodiment of the invention also provides a preparation method of the display panel, which comprises the following steps:

providing a substrate;

preparing a device layer on the substrate, the device layer including a plurality of light emitting cells;

preparing a barrier layer on one side, far away from the substrate, of the device layer by using an FMM (frequency modulation method), wherein the barrier layer comprises a plurality of barrier subunits, and a gap is formed between every two adjacent barrier subunits;

The embodiment of the invention also provides a display device which comprises the display panel disclosed by any one of the embodiments or the display panel prepared by the preparation method of the display panel.

The display panel comprises a device layer and a blocking layer which are arranged in a stacked mode, wherein the device layer comprises a plurality of light emitting units, the blocking layer comprises a plurality of blocking sub-units, a gap is reserved between every two adjacent blocking sub-units, and the light emitting units are covered by orthographic projections of the blocking sub-units on the device layer. Through set up the barrier layer of patterning in display panel, reached display panel when curling and buckling, the unable persistence of stress on barrier layer is piled up the transmission, can alleviate the stress on barrier layer, can effectively avoid the emergence of obscission, has effectively improved display panel's life.

Drawings

Fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of another display panel according to an embodiment of the invention.

Fig. 3 is a schematic step diagram illustrating a method for manufacturing a display panel according to an embodiment of the invention.

Fig. 4 is a schematic structural diagram of a display device according to an embodiment of the invention.

Reference numerals:

1-a display panel; 2-a shell; 3-a display device;

20-a device layer; 220-a light emitting unit;

40-a light extraction layer;

60-a barrier layer; 620-blocking subunit; 640-a light blocking unit.

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.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description of the present invention, but do not indicate that the indicated device or element must have a specific orientation, and thus, should not be construed as limiting the present invention. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The inventor finds that the display panel in the prior art is easy to fall off at the barrier layer when being bent through long-term research. The specific analysis process is as follows: the two main reasons for causing the display panel to fall off are that the adhesion between the film layers of the OLED display panel is weak, and the stress distribution in the whole OLED device is not uniform. Because the barrier layer usually adopts the lithium fluoride film layer, the main component of the barrier layer is the ionic salt, the lithium fluoride film layer is crisp, and Common Mask (CMM) is used for whole-surface evaporation, so that stress is not easy to release when the flexible OLED display panel is bent, and the stress is stacked and stacked to cause falling and peeling. Therefore, under the combined action of the two factors, the flexible OLED display panel product is easy to fall off at the barrier layer when being bent. In the current device structure, the barrier layer has the effect of adjusting and controlling the viewing angle, and is a layer which can not be lost in the display panel, so an improvement mode is urgently needed.

Based on this, the application provides a display panel, a preparation method thereof and a display device, which can effectively solve the problem that a barrier layer in the prior art is easy to fall off and separate, and are specifically as follows.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a display panel according to an embodiment of the present invention, where the display panel 1 specifically includes a device layer 20 and a barrier layer 60. Wherein the device layer 20 includes a plurality of light emitting cells 220; the blocking layer 60 is located on one side of the light emitting surface of the device layer 20, the blocking layer 60 includes a plurality of blocking sub-units 620, a space is provided between two adjacent blocking sub-units 620, and an orthographic projection of the blocking sub-units 620 on the device layer 20 covers the light emitting unit 220.

It is to be understood that the meaning of "a plurality" in the embodiments of the present application is two or more.

It is understood that the device layer 20 includes a Cathode (Cathode), an Electron Injection Layer (EIL), an Electron Transport Layer (ETL), an emission layer (EML), a Hole Transport Layer (HTL), a Hole Injection Layer (HIL), an Anode (Anode), and the like, which are sequentially stacked. One side that barrier layer 60 was kept away from to device layer 20 still includes the array substrate, and is concrete, and the array substrate includes carrier substrate and range upon range of a plurality of function retes that set up on carrier substrate, and carrier substrate can be flexible substrate to realize the flexible function of buckling, a plurality of function retes can form the pixel drive circuit that the array was arranged, a plurality of luminescence unit one-to-one in this pixel drive circuit and the device layer 20, with the luminous display of drive luminescence unit.

It will be appreciated that the barrier layer 60 functions specifically as follows: the blocking layer 60 may serve as an nth layer of a bragg reflector, so that optical energy emitted from the device layer 20 may generate destructive interference at a cross section to obtain strong reflected light, and cooperate with a microcavity effect inside the device layer 20, thereby improving light extraction efficiency.

It is understood that the orthographic projection of the blocking subunit 620 on the device layer 20 covers the light emitting unit 220, which means that the orthographic projection of the blocking subunit 620 on the device layer 20 is greater than or equal to the area of the light emitting unit 220, and may be specifically set according to practical situations, and is not specifically limited herein.

It is understood that the light emitting unit 220 may include one sub-pixel unit, for example: the red sub-pixel unit, the blue sub-pixel unit, or the green sub-pixel unit, and the light emitting unit 220 may further include more than two sub-pixel units, for example, three sub-pixel units, and four sub-pixel units, which may be set according to actual situations. In fig. 1, the light emitting unit 220 includes a sub-pixel unit as an example.

It will be appreciated that the display panel 1 may further comprise an encapsulation layer (not shown) on the side of the barrier layer 60 facing away from the device layer 20. Specifically, the encapsulation layer may be a manner in which an organic layer and an inorganic layer are sequentially stacked, for example, the encapsulation layer includes a first inorganic layer, a first organic layer, and a second inorganic layer that are sequentially stacked, where the first inorganic layer is closer to the blocking layer 60 than other encapsulation film layers, and at this time, the first inorganic layer fills the gap between the adjacent blocking sub-units 620, which may further improve the capability of blocking external water and oxygen of the display panel 1.

It is understood that, in this embodiment, two layers, namely the device layer 20 and the barrier layer 60, are stacked, and in other embodiments, other functional film layers may be further included between the two layers, namely the device layer 20 and the barrier layer 60, according to the actual situation, which is not specifically limited herein.

The application provides a display panel has set up the barrier layer of patterning through the one side on device layer, has reached display panel when curling and buckling, and the transmission is piled up to the unable persistence of barrier layer's stress, can alleviate the stress on barrier layer, can effectively avoid the emergence of the phenomenon of droing, has effectively improved display panel's life.

In an embodiment, the display panel 1 further includes a light extraction layer 40, and the device layer 20, the light extraction layer 40 and the barrier layer 60 are sequentially stacked, specifically referring to fig. 2, where fig. 2 is a schematic structural diagram of another display panel provided in an embodiment of the present invention. In other embodiments, the three layers, i.e., the device layer 20, the light extraction layer 40 and the blocking layer 60, may further include other functional film layers according to practical situations, and are not particularly limited herein.

In one embodiment, the area of the orthographic projection of the blocking subunit 620 on the device layer 20 is 1.0-1.5 times the area of the light emitting unit 220 to ensure that the orthographic projection of the blocking subunit 620 on the device layer 20 covers the light emitting unit 220. Preferably, the area of the orthographic projection of the blocking subunit 620 on the device layer 20 is 1.1-1.2 times the area of the light emitting unit 220. By setting the area of the orthographic projection of the blocking sub-unit 620 on the device layer 20 within this range, the light emitting unit 220 can be completely covered, and the optical performance of the display panel 1 can be effectively ensured.

In one embodiment, the display panel 1 may be divided into a central region and a peripheral region. In the peripheral region of the display panel 1, the area of the orthographic projection of the blocking sub-unit 620 on the device layer 20 is 1.0-1.2 times the area of the light emitting unit 220. In the central region of the display panel 1, the area of the orthographic projection of the blocking subunit 620 on the device layer 20 is 1.2 to 1.5 times that of the light-emitting unit 220, and by this arrangement, the optical performance of the display panel 1 can be further effectively ensured.

In one embodiment, the shape of the orthographic projection of the blocking subunit 620 on the device layer 20 includes a polygon, a triangle, a circle, an ellipse or an irregular figure, as long as the orthographic projection of the blocking subunit 620 on the device layer 20 covers the light emitting unit 220, and the orthographic projection shape of the blocking subunit 620 on the device layer 20 is not particularly limited.

In one embodiment, barrier layer 60 is a lithium fluoride (LiF) film layer and, accordingly, barrier subunit 620 is a lithium fluoride subunit.

In one embodiment, an elastic material, such as a polyurethane elastomer (TPU), is disposed in the gap between two adjacent blocking sub-units 620, such an arrangement can effectively relieve the stress generated when the display panel 1 is curled and bent, and avoid the problem of falling off and separation of the film layer in the display panel 1. In other embodiments, the gap between two adjacent barrier subunits 620 may further include other materials, such as polymethyl methacrylate, and the polymethyl methacrylate may be formed in the gap between two adjacent barrier subunits 620 by inkjet printing, which may effectively simplify the process steps.

In one embodiment, a light blocking unit 640 is provided in a gap between two adjacent blocking sub-units 620. By arranging the light blocking unit 640 between the two adjacent blocking sub-units 620, the optical crosstalk between the adjacent light emitting units 220 can be avoided, the display effect of the display panel is improved, and meanwhile, the stress generated when the display panel is curled and bent can be effectively relieved due to the fact that the light blocking unit 640 is not of a whole-layer structure. In one embodiment, the light blocking unit 640 has the same thickness as the blocking subunit 620. By setting the thickness of the light blocking unit 640 between the blocking subunits 620 to be the same as that of the blocking subunit 620, the phenomenon that the water and oxygen blocking capability of the packaging layer is reduced due to obvious steps in the subsequent preparation of the packaging layer is avoided.

In one embodiment, the orthographic projection of the light blocking unit 640 between two adjacent blocking sub-units 620 on the device layer 20 includes a polygon, a triangle, a circle, an ellipse or an irregular figure. Specifically, the polygon may be a rectangle, a trapezoid, or the like, and the irregular figure may include any figure that cannot be termed as a shape or described. In other embodiments, the light blocking unit 640 may have other shapes as long as it can satisfy that the light blocking unit 640 between two adjacent blocking sub-units 620 does not completely fill the gap between two adjacent blocking sub-units 620, and the light blocking unit 640 may be specifically configured according to actual situations. Through setting up the graphical light blocking unit 640, can further release the stress that piles up barrier layer 60 when display panel 1 buckles, can also increase the area of contact between first inorganic rete and the barrier layer 60 when the first inorganic rete of packaging layer deposit simultaneously, and then increase the rete adhesion.

In an embodiment, the orthographic projection of the light blocking unit 640 between two adjacent blocking sub-units 620 on the device layer 20 includes two regular patterns concentrically arranged, for example, two circles concentrically arranged, triangles concentrically arranged, rectangles concentrically arranged, and may also be two circles concentrically arranged, triangles concentrically arranged, rectangles concentrically arranged, and circles concentrically arranged, and the like, and the arrangement may be specifically configured according to actual conditions, and this arrangement may further release the stress accumulated on the blocking layer 60 when the display panel 1 is bent on the basis of ensuring the display effect of the display panel 1. It is known that a concentric arrangement is one in which the figures have the same center.

In one embodiment, the material of the light blocking unit 640 includes a cyclized rubber-based negative photoresist or a black glue. The cyclized rubber negative photoresist or the black photoresist is a common light-blocking material, has excellent light-blocking property, can effectively avoid optical crosstalk between adjacent light-emitting units 220, and has stable performance, low price and convenient purchase channels.

In one embodiment, the light emitting unit 220 may include at least two adjacent sub-pixel units. In particular, the orthographic projection of the blocking sub-unit 620 on the device layer 20 may cover two, three or four adjacent sub-pixel units. The arrangement can effectively simplify the preparation process of the barrier layer 60 and improve the production efficiency.

It can be known that, when the orthographic projection of the blocking sub-unit 620 on the device layer 20 covers at least two adjacent sub-pixel units, the area of the orthographic projection of the blocking sub-unit 620 on the device layer 20 is 1.0 to 1.5 times the total area of the covered at least two adjacent sub-pixel units, and this arrangement can further improve the optical performance of the display panel 1.

It is known that the at least two adjacent sub-pixel units may include at least two adjacent red sub-pixel units, at least two adjacent green sub-pixel units, at least two adjacent blue sub-pixel units, at least two adjacent red sub-pixel units and green sub-pixel units, at least two adjacent red sub-pixel units and blue sub-pixel units, or at least two adjacent blue sub-pixel units and green sub-pixel units, which may be specifically configured according to practical situations and is not specifically limited herein.

In other embodiments, the orthographic projection of the partial blocking subunit 620 on the device layer 20 may cover one sub-pixel unit, and the orthographic projection of the partial blocking subunit 620 on the device layer 20 may cover at least two adjacent sub-pixel units. It is also possible that the orthographic projection of all the blocking sub-units 620 on the device layer 20 covers one sub-pixel unit or the orthographic projection of all the blocking sub-units 620 on the device layer 20 covers at least two adjacent sub-pixel units, and the setting is performed according to the requirement.

In one embodiment, the display panel 1 may be divided into a central region and a peripheral region. In the peripheral area of the display panel 1, the orthographic projection of the blocking sub-unit 620 on the device layer 20 covers one sub-pixel unit. In the central area of the display panel 1, the orthographic projection of the blocking sub-unit 620 on the device layer 20 covers at least two adjacent sub-pixel units. By the arrangement, the display effect of the display panel 1 can be optimized, and the preparation process of the blocking subunit 620 can be simplified.

In one embodiment, the light emitting units 220 are arranged in an array, and the blocking sub-units 620 are also arranged in an array. The arrangement mode can effectively simplify the preparation process of the barrier layer 60 and improve the production efficiency.

In one embodiment, the display panel 1 specifically includes a device layer 20 and a light extraction layer 40, which are sequentially stacked, and two barrier layers 60. Wherein the device layer 20 includes a plurality of light emitting cells 220; the light extraction layer 40 is located on one side of the device layer 20; two-layer barrier layer 60 is located the one side that device layer 20 was kept away from to light extraction layer 40, every layer of barrier layer 60 all includes a plurality of barrier subunit 620, and adjacent two have the interval between blocking subunit 620, every layer blocks that the orthographic projection of subunit 620 on device layer 20 all covers luminescence unit 220, adjacent two in two-layer barrier layer 60 block that the orthographic projection of interval between subunit 620 on device layer 20 is not overlapped, this kind of setting up the mode is on the basis of guaranteeing display panel 1's display effect, can further effectively avoid the emergence of display panel 1's rete obscission, the effectual life who improves display panel 1.

An embodiment of the present invention further provides a method for manufacturing a display panel, specifically, as shown in fig. 3, fig. 3 is a schematic step diagram of the method for manufacturing a display panel according to the embodiment of the present invention, and the method may specifically include the following steps.

S101, providing a substrate.

It is understood that the substrate may be a flexible substrate, and the specific material may be a PI (polyimide) substrate.

S102, preparing a device layer on the substrate.

It is understood that the device layer includes a plurality of light emitting cells. Specifically, the light emitting unit may include one sub-pixel unit, such as a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit, and may further include more than two sub-pixel units, such as three sub-pixel units.

It is understood that the device layers may include a cathode, an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and an anode.

And S103, preparing a barrier layer on the side, far away from the substrate, of the device layer by using an FMM.

Alternatively, a light extraction layer may be fabricated on the side of the device layer remote from the substrate, and a barrier layer may be fabricated using an FMM on the side of the light extraction layer remote from the device layer.

Specifically, the barrier layer is a lithium fluoride film layer.

It can be understood that the light extraction layer adjusts the light extraction efficiency and spectrum by adjusting the optical cavity length of the device layer.

It can be understood that in this embodiment, a barrier layer is prepared by using a Fine Metal Mask (FMM) in an evaporation manner, and the obtained barrier layer may specifically include a plurality of blocking subunits, and an orthographic projection of the blocking subunit on the device layer covers the light emitting unit.

It is understood that the FMM may include a plurality of openings arranged in an array, the positions of the openings in the FMM are evaporated to form blocking sub-units on one side of the light extraction layer, and the positions of the openings in the FMM are not opened to form gaps between the blocking sub-units, so that a gap is formed between two adjacent blocking sub-units.

It can be understood that, when the FMM is used to evaporate the blocking layer, the size of the opening on the FMM should correspond to the size of the light-emitting unit and be larger than the light-emitting unit, so that the light-emitting unit is covered by the orthographic projection of the blocking sub-unit on the device layer after effective evaporation.

Through adopting the mode of FMM coating by vaporization barrier layer, can effectively avoid using CMM whole face coating by vaporization among the prior art, and the difficult problem of releasing of stress when causing flexible OLED display panel to buckle.

According to the preparation method of the display panel, the patterned barrier layer is arranged on one side of the device layer in the display panel, so that the stress of the barrier layer cannot be continuously accumulated and transferred when the display panel is curled and bent, the stress of the barrier layer can be relieved, the falling phenomenon can be effectively avoided, and the service life of the display panel is effectively prolonged.

In an embodiment of the present invention, a display device is further provided, and specifically referring to fig. 4, the display device 3 includes a display panel 1 and a housing 2. The specific manner of the display panel 1 may be shown in any one of the above embodiments or a combination of at least one of the above embodiments, and is not limited in detail herein. The display device 3 in the embodiment of the present invention includes, but is not limited to, a mobile phone, a Personal Digital Assistant (PDA), a tablet computer, a paper book, a television, a door lock, a smart phone, a console, and other devices having a fingerprint recognition display function, and the form of the display device 3 in the embodiment of the present invention is not limited.

The beneficial effects of the display device in this embodiment can be seen from the description of the display panel, which is not repeated herein.

All possible combinations of the technical features of the above embodiments may not be described for the sake of brevity, but should be considered as within the scope of the present disclosure as long as there is no contradiction between the combinations of the technical features.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the scope of the present invention, which is intended to cover any modifications, equivalents and the like included within the spirit and scope of the present invention.

Claims

1. A display panel, comprising:

wherein, the orthographic projection of the blocking subunit on the device layer covers the light-emitting unit, and a light blocking unit is arranged in the gap between two adjacent blocking subunits.

2. The display panel according to claim 1, wherein an area of an orthographic projection of the blocking sub-unit on the device layer is 1.0-1.5 times an area of the light emitting unit.

3. The display panel according to claim 2, wherein an area of an orthographic projection of the blocking sub-unit on the device layer is 1.1-1.2 times an area of the light emitting unit.

4. The display panel according to claim 3, wherein the light blocking unit has the same thickness as the blocking sub-unit.

5. The display panel according to claim 3 or 4, wherein an orthographic projection of the light blocking unit on the device layer between two adjacent blocking subunits comprises a polygon, a triangle, a circle, an ellipse or an irregular figure.

6. The display panel according to claim 5, wherein the material of the light blocking unit comprises cyclized rubber-based negative photoresist or black glue.

7. The display panel according to claim 1 or 2, wherein the light emitting unit comprises at least two adjacent sub-pixel units.

8. The display panel of claim 7, wherein the at least two adjacent sub-pixel units comprise at least two adjacent red sub-pixel units, at least two adjacent green sub-pixel units, at least two adjacent blue sub-pixel units, at least two adjacent red and green sub-pixel units, at least two adjacent red and blue sub-pixel units, or at least two adjacent blue and green sub-pixel units.

9. A method for manufacturing a display panel, comprising:

providing a substrate;

preparing a barrier layer on one side of the device layer far away from the substrate by using an FMM (frequency modulated manufacturing), wherein the barrier layer comprises a plurality of barrier subunits, and a gap is formed between every two adjacent barrier subunits;

10. A display device comprising the display panel according to any one of claims 1 to 8, or a display panel produced by the production method for a display panel according to claim 9.