CN112640150A

CN112640150A - Flexible display panel and flexible display device

Info

Publication number: CN112640150A
Application number: CN201880095922.1A
Authority: CN
Inventors: 陈羿恺; 袁雄; 赖瑞云; 舒鹏; 王超
Original assignee: Shenzhen Royole Technologies Co Ltd
Current assignee: Shenzhen Royole Technologies Co Ltd
Priority date: 2018-12-13
Filing date: 2018-12-13
Publication date: 2021-04-09
Also published as: WO2020118626A1

Abstract

The application discloses flexible display panel and flexible display device, flexible display panel (10) include: the OLED device comprises a thin film transistor substrate (11), a pixel defining layer (12), an OLED device (13), a thin film packaging layer (14) and a buffer layer (15), wherein the thin film packaging layer (14) comprises a side face, and the buffer layer (15) is stacked on the side face of the thin film packaging layer (14). When folding, buffer layer (15) can prevent that two adjacent film packaging layer (14) from directly extruding each other and colliding, cushions the collision of two film packaging layer (14), has reduced film packaging layer (14) and has appeared the cracked probability of side, and then reduces the side of film packaging layer (14) and breaks and make the probability of appearance of the phenomenon of water oxygen entering OLED device to improve flexible display panel's life relatively.

Description

Flexible display panel and flexible display device

Technical Field

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

Background

The Organic Light-Emitting Diode (OLED) display technology has the characteristics of active Light emission, low-voltage driving, high brightness, full color and the like, and by virtue of various advantages, the OLED display technology is widely applied to the fields of mobile phones, computers, televisions and the like.

When the flexible display panel is manufactured, a thin film encapsulation layer is generally required to be deposited on the OLED device, and the thin film encapsulation layer can block moisture or isolate oxygen from entering the OLED device so as to protect the OLED device from being damaged, so that the service life of the OLED device is prolonged.

However, since the flexible display panel has a bending and folding property, when the flexible display panel is folded, the thin film encapsulation layer is easily broken or peeled off due to stress, so that moisture or oxygen enters the OLED device to cause the OLED device to fail.

Disclosure of Invention

The embodiment of the application provides a flexible display panel and a flexible display device, which can relatively prolong the service life of the flexible display panel.

The embodiment of the application solves the technical problem and provides the following technical scheme:

a flexible display panel comprising:

a thin film transistor substrate including a deposition surface;

a plurality of pixel defining layers sequentially arranged on the deposition surface;

a plurality of OLED devices which are sequentially arranged on the deposition surface, and each OLED device is positioned between every two adjacent pixel defining layers;

each thin film packaging layer is packaged on the corresponding OLED device; and

and the buffer layer is stacked on the side surface of the film packaging layer.

an embodiment of the present application provides a flexible display device, including:

a housing; and the number of the first and second groups,

the flexible display panel can be accommodated in the shell.

Compared with the prior art, in the flexible display panel that this application embodiment provided, the buffer layer is range upon range of in the side of film packaging layer, when folding, the buffer layer can prevent that two adjacent film packaging layers from directly extruding and colliding mutually, cushion the collision of two film packaging layers, the cracked probability of side has been reduced to the film packaging layer, and then the side that reduces the film packaging layer breaks and makes the probability of appearance of the phenomenon that water oxygen got into OLED device, thereby improve flexible display panel's life relatively.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly described below. It is obvious that the drawings described below are only some embodiments of the application, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

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

FIG. 1b is a schematic diagram of a buffer layer stacked on a second side of a thin film encapsulation layer according to an embodiment of the present disclosure;

FIG. 1c is a schematic diagram of a buffer layer between every two adjacent thin film encapsulation layers according to an embodiment of the present disclosure;

FIG. 1d is a schematic diagram of a buffer layer stacked on a thin film encapsulation layer according to another embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a flexible display panel according to another embodiment of the present application;

fig. 3a to 3d are schematic structural diagrams of OLED devices provided in various embodiments of the present application;

fig. 4a to 4d are schematic structural diagrams of a flexible display panel with a thin film encapsulation layer according to various embodiments of the present disclosure;

fig. 5 is a schematic structural diagram of a flexible display device according to an embodiment of the present application.

Detailed Description

In order to facilitate an understanding of the present application, the present application is described in more detail below with reference to the accompanying drawings and specific embodiments. It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present. The terms "vertical", "horizontal", "left", "right", "inside", "outside" and the like used in the present specification are for illustrative purposes only and express only a substantial positional relationship, for example, with respect to "vertical", if a positional relationship is not strictly vertical for the purpose of achieving a certain object, but is substantially vertical, or utilizes the property of being vertical, it belongs to the category of "vertical" described in the present specification.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It is to be understood that, as shown herein, the positional relationship between one or more layers of the substance involved in the embodiments of the present application, such as the terms "stacked" or "formed" or "applied" or "disposed", is expressed using terms such as: any terms such as "stacked" or "formed" or "applied" may cover all manner, kinds and techniques of "stacked". For example, sputtering, plating, molding, Chemical Vapor Deposition (CVD), Physical Vapor Deposition (PVD), evaporation, Hybrid Physical-Chemical Vapor Deposition (HPCVD), Plasma Enhanced Chemical Vapor Deposition (PECVD), Low Pressure Chemical Vapor Deposition (LPCVD), and the like.

In addition, the technical features mentioned in the different embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1a, a flexible display panel 10 provided in the embodiment of the present application includes: a thin film transistor substrate 11, a plurality of pixel defining layers 12, a plurality of OLED devices 13, a plurality of thin film encapsulation layers 14, and a buffer layer 15.

The thin film transistor substrate 11 comprises a deposition surface 110, each pixel defining layer 12 is sequentially arranged on the deposition surface 110 of the thin film transistor substrate 11, each OLED device 13 is located between every two adjacent pixel defining layers 12, each thin film encapsulation layer 14 is encapsulated on the corresponding OLED device 13, and the buffer layer 15 is laminated on the side surface of the thin film encapsulation layer 14.

When folding, film packaging layer 14 is crooked and when crooked following flexible display panel 10, buffer layer 15 can prevent that two adjacent film packaging layers 14 from directly extruding each other and colliding, cushions the collision of two film packaging layers, has reduced film packaging layer 14 and has appeared the cracked probability of side, and then reduces the side of film packaging layer 14 and breaks and make the probability of appearance of the phenomenon that water oxygen got into OLED device to improve flexible display panel's life relatively. Also, since the buffer layer 15 can protect the thin film encapsulation layer 14 from being compressed by an excessive compressive stress, the user can relatively fold the flexible display panel 10 at a larger folding angle, and thus, the buffer layer 15 can improve the lateral extensibility of the flexible display panel 10, compared to the folding angle of a conventional folding flexible display panel.

With continued reference to fig. 1a, the side of the film encapsulation layer 14 includes a first side 141 and a second side 142 opposite to each other, and in some embodiments, the position of the buffer layer 15 is not limited in any way, for example, as shown in fig. 1a, the buffer layer 15 is stacked on the first side 141 of the film encapsulation layer 14, and when folded, the buffer layer 15 can prevent the film encapsulation layer 14 and the adjacent left film encapsulation layer from colliding with each other in a pressing manner, so as to reduce the probability of side edge breakage of the film encapsulation layer 14.

For another example, as shown in fig. 1b, the buffer layer 15 is stacked on the second side 142 of the film encapsulation layer 14, and when folded, the buffer layer 15 can prevent the film encapsulation layer 14 and the adjacent right film encapsulation layer from being pressed and collided with each other, so as to reduce the probability of side edge breakage of the film encapsulation layer 14.

In some embodiments, no limitation is made to the number of buffer layers 15, for example, the number of buffer layers 15 is selected to be a preset number, wherein the preset number is smaller than the number of OLED devices. For another example, the number n of the buffer layers 15 is m +1, where m is the number of the OLED devices, and with the number of the buffer layers 15, the thin film encapsulation layers encapsulated on each OLED device in the flexible display panel 10 can be fully protected.

In some embodiments, when the number of the buffer layers 15 is plural, each buffer layer 15 is laminated between each adjacent two thin film encapsulation layers 14. Referring to fig. 1c, the buffer layer 15 is stacked between the first thin film encapsulation layer 143 and the second thin film encapsulation layer 144. When the film is folded in the first direction X1 or the second direction X2, the buffer layer 15 can buffer the extrusion collision between the first film encapsulation layer 143 and the second film encapsulation layer 144, so as to reduce the probability of side edge breakage of the first film encapsulation layer 143 or the second film encapsulation layer 144.

In some embodiments, referring to fig. 1d, when each buffer layer 15 is stacked between every two adjacent thin film encapsulation layers 14 and is folded in the first direction X1 or the second direction X2, the buffer layer 15 can buffer the compression impact between the two adjacent thin film encapsulation layers 143, so as to reduce the probability of side edge breakage of each thin film encapsulation layer when the thin film encapsulation layer is subjected to the compression impact in the first direction X1 or the second direction X2.

In some embodiments, the buffer layer 15 may be formed on the side of the thin film encapsulation layer 14 by an inkjet printing method, a spin coating method, or a spray coating method.

In some embodiments, the buffer layer 15 includes an organic film layer, wherein the organic film layer may be selected from Hexamethyldisiloxane (HMDSO), Acrylic (PMMA), and the like. The organic film layer is selected as the buffer layer 15, which can improve the lateral tension of the film encapsulation layer, reduce the influence of stress concentrated on the side surface of the film encapsulation layer, and avoid the film encapsulation layer from cracking. On the other hand, it can also block moisture or oxygen from entering the OLED device 13.

The thin film transistor substrate 11 is used for driving each OLED device 13 to emit light, and in some embodiments, the thin film transistor substrate 11 includes a substrate and a thin film transistor formed on the substrate, wherein the thin film transistor may be formed on the substrate by using any suitable process.

The substrate may use a flexible substrate such as a material including thin glass, metal foil, or a plastic base, etc., which has flexibility, for example, the plastic base has a flexible structure including a resin such as Polyimide (PI), Polycarbonate (PC), polyethylene glycol terephthalate (PET), Polyethersulfone (PES), polyethylene film (PEN), Fiber Reinforced Plastic (FRP), etc., coated on both sides of a base film.

The thin film transistor substrate 11 may adopt a Passive Matrix (PMOLED) driving method and an Active Matrix (AMOLED) driving method. When the Thin film transistor substrate 11 adopts a PMOLED mode, a Thin-film transistor (TFT) can be selected as a switching tube, and static driving or dynamic driving is realized through a scanning effect. When the Thin Film Transistor substrate 11 is an AMOLED, a Low Temperature polysilicon Thin Film Transistor (LTP-Si TFT), an amorphous silicon TFT, a polysilicon TFT, an oxide semiconductor TFT, an organic TFT, or the like may be selected as a switching tube.

In some embodiments, the thin film transistor may be a transparent transistor, which is a TFT transistor manufactured from opaque silicon by replacing the related art TFT transistor manufactured using a transparent substance such as zinc oxide or titanium dioxide. In addition, the transparent electrode may be composed of a material such as Indium Tin Oxide (ITO) or graphene. Graphene has a honeycomb lattice plane structure composed of carbon atoms, and has transparency. In addition, the transparent organic light emitting layer may be implemented using various substances.

The pixel defining layers 12 define the location of the respective OLED devices 13, wherein the shape of each pixel defining layer 12 may be any suitable shape, such as trapezoidal, inverted trapezoidal, rectangular, square, and the like.

In some embodiments, referring to fig. 2, the pixel defining layer 12 includes a third inorganic layer 121 and a fourth inorganic layer 122, and the third inorganic layer 121 covers the side 12a of one of the two OLED devices adjacent to the pixel defining layer 12. The fourth inorganic layer 122 covers the side 12b of the other of the two OLED devices adjacent to the pixel defining layer 12.

The third inorganic layer 121 and the fourth inorganic layer 122 are used to block moisture or oxygen from entering the OLED device from the side of the OLED device, so as to avoid damaging the OLED device, thereby further improving the service life of the OLED.

In some embodiments, the third inorganic layer 121 and the fourth inorganic layer 122 both contain inorganic substances, alternatively, the third inorganic layer 121 may include a silicon nitride layer, alternatively, the fourth inorganic layer 122 may include a silicon nitride layer, alternatively, both the third inorganic layer 121 and the fourth inorganic layer 122 may include a silicon nitride layer. The silicon nitride layer has better compactness and better water and oxygen resistance efficiency.

In some embodiments, with reference to fig. 2, the pixel defining layer 12 further includes a material filling layer 123, and the material filling layer 123 is filled between the third inorganic layer 121 and the fourth inorganic layer 122.

When folding, material filling layer 123 can assist buffer layer 15 to improve the cushion effect, further reduces the direct extrusion stress that receives of film packaging layer 14 to film packaging layer 14 has been protected better, has further reduced film packaging layer 14 and has appeared the cracked probability of side.

In some embodiments, the material filling layer 123 includes an organic film layer, an inorganic film layer, or a mixture of organic and inorganic film layers that are alternately stacked.

When the material filling layer 123 is an organic film layer and is folded, the material filling layer 123 can assist the buffer layer 15 to improve the buffer force and reduce the extrusion stress directly applied to the film packaging layer 14, so that the film packaging layer 14 is better protected, and the probability of side edge fracture of the film packaging layer 14 is further reduced.

When the material filling layer 123 is an inorganic film layer, on one hand, the material filling layer 123 can prevent moisture or oxygen from entering the OLED device 13, so that the OLED device 13 is protected, and on the other hand, when the material filling layer 123 is folded, the buffer layer 15 can be assisted to improve the buffer force, and the extrusion stress directly received by the thin film packaging layer 14 is reduced.

When the pixel defining layer 12 is a mixture of organic and inorganic layers that are alternately stacked, the material filling layer 123 integrates the effects of the inorganic and organic layers.

In some embodiments, with continued reference to fig. 2, the third inorganic layer 121 includes: the first hook 1211 and the first extension 1212.

The first raised portion 1211 covers a portion of the top 12c of the material filling layer 123.

The first extending portion 1212 is connected to the first hooking portion 1211, and the first extending portion 1212 covers the side surface 12a of one of the two OLED devices adjacent to the pixel defining layer 12.

The first hooking portion 1211 can be tightly stacked on a partial region of the top 12c of the material filling layer 123, and the first extending portion 1212 is also tightly stacked on the side 12a of the OLED device by the association of the first hooking portion 1211. With the third inorganic layer 121 of this structure, on the one hand, the third inorganic layer 121 entirely surrounds the side of the OLED device, thereby blocking moisture or oxygen from entering the OLED device in all directions. On the other hand, the third inorganic layer 121 can be stably and reliably contacted with the OLED device by the action of the first hook 1211.

In some embodiments, with continued reference to fig. 2, the fourth inorganic layer 122 includes: a second hook 1221 and a second extension 1222.

The second raised portion 1221 covers another partial region of the top portion 12c of the material filling layer 123, and the second raised portion 1221 is opposite to the first raised portion 1211.

The second extension 1222 is in contact with the second hooking portion 1221, and the second extension 1222 covers the side 12b of the other of the two OLED devices adjacent to the pixel defining layer 12.

The second hook 1221 can be tightly laminated on another partial region of the top 12c of the material filling layer 123, and the second extension 1222 is also tightly laminated on the side 12a of the OLED device through the association of the second hook 1221. With the fourth inorganic layer 122 of this structure, on the one hand, the fourth inorganic layer 122 entirely surrounds the side of the OLED device, thereby blocking moisture or oxygen from entering the OLED device in all directions. On the other hand, the fourth inorganic layer 122 can be stably and reliably brought into contact with the OLED device by the second hooking portion 1221.

In some embodiments, a side of the buffer layer 15 close to the thin film transistor substrate 11 fills a gap between the first raised portion 1211 and the second raised portion 1221 and abuts against a top of the material filling layer 123. Therefore, the buffer layer 15 can buffer not only the compressive stress between the adjacent two thin film encapsulation layers but also the compressive stress between the adjacent two pixel defining layers 12.

In some embodiments, the buffer layer 15, the first raised portion 1211 and the second raised portion 1221 together cover the top of the material filling layer 123, so that the buffer layer 15 can completely enclose one side of the thin film encapsulation layer 11, and completely protect the thin film encapsulation layer 11.

The OLED device 13 is adapted to emit light under the influence of an external voltage, and the OLED device 13 may be manufactured using any suitable process.

In some embodiments, referring to fig. 3a, OLED device 13 includes: an anode 131, a cathode 132, and an organic functional layer 133.

The anode 131 is stacked on the deposition surface 110 of the tft substrate 11, the anode 131 is located between every two adjacent pixel defining layers 12, the organic functional layer 133 is stacked on the anode 131 and located between every two adjacent pixel defining layers 12, the cathode 132 is stacked on the organic functional layer 133 and away from the anode 131, and the thin film encapsulation layer 14 is encapsulated on the cathode 132.

In electroluminescence, an external voltage is applied between the anode 131 and the cathode 132, and holes are released from the anode 131 by the external voltage. The cathode releases electrons under the action of an external voltage. The holes are transferred to the organic functional layer 133, and similarly, the electrons are transferred to the organic functional layer 133, when the electrons and the holes meet and are combined in the organic functional layer 133, an exciton in an excited state is formed, the exciton transfers energy to the light-emitting molecule under the action of an electric field, the electron which excites the light-emitting molecule is transited from a ground state to an excited state, the electron of the light-emitting molecule releases energy mainly in the form of light and returns to a stable ground state, and thus electroluminescence is generated.

In some embodiments, the anode 131 may be a transmissive electrode or a transflective electrode.

In some embodiments, the cathode 132 may be a transmissive electrode or a transflective electrode, or may be a transmissive electrode having a multi-layer structure.

In some embodiments, one of the anode 131 and the cathode 132 is a transparent electrode, and the other is a transparent electrode or an opaque electrode. For example, the anode is an indium tin oxide transparent electrode, and the cathode 132 is made of a material such as magnesium, magnesium-silver alloy, calcium, or lithium-aluminum alloy.

In some embodiments, the organic functional layer 133 is prepared by doping a proportion of an organic light emitting material in a host material. The luminescent material has a high quantum efficiency and sufficient thermal stability to sublime without decomposition. When the electrons and the holes meet in the organic functional layer 133, the electrons are continuously filled from the high orbit into the holes of the low orbit, thereby releasing energy.

The organic light-emitting material can be selected from small molecule-based OLEDs which take organic dyes or pigments and the like as light-emitting materials, or can also be selected from high molecule-based OLEDs which take conjugated high molecules as light-emitting materials, the small molecule-based OLEDs can adopt a vacuum thermal evaporation process, and the high molecule-based OLEDs can adopt a spin coating or ink-jet process. The organic light-emitting material may be a fluorescent material or a phosphorescent material depending on the kind of the light-emitting exciton.

Referring to fig. 3b, the organic functional layer 133 includes a hole injection layer 1331, a hole transport layer 1332, an organic light emitting layer 1333, an electron transport layer 1334 and an electron injection layer 1335, which are sequentially formed.

The hole injection layer 1331 can efficiently inject holes into the hole transport layer 1332 and into the organic light emitting layer 1333 through the hole transport layer 1332 so that the holes meet electrons in the organic light emitting layer 1333.

The hole transport layer 1332 may include carbazole-based derivatives such as n-phenylcarbazole, polyvinylcarbazole, etc., fluorine-based derivatives, etc.

The organic light emitting layer 1333 may include an organic light emitting material. In some embodiments, the organic light emitting material may include a material emitting red, green, or blue light and a fluorescent material or a phosphorescent material. In some embodiments, the organic light emitting layer 1333 may include two or more light emitting materials.

In some embodiments, the organic light emitting layer 1333 may include a host and a dopant. As the main component, for example, Alq can be used₃(tris (8-quinolinolato) aluminum), and the like.

In some embodiments, electron transport layer 1334 comprises, for example, Alq₃(tris (8-hydroxyquinoline) aluminum), TPBi (1,3, 5-tris (1-phenyl-1H-benzo [ d ]]Imidazol-2-yl) phenyl), and the like.

In some embodiments, the electron injection layer 1335 is made of an organometallic complex or an inorganic substance, in some embodiments, the electron injection layer 1335 is made of an alkali metal compound, for example, the electron injection layer 1335 is made of LiF, LiQ, NaF, CsF, Cs₂CO ₃Or made of other suitable material.

In some embodiments, the electron injection layer 1335 can effectively inject electrons into the electron transport layer 1334 and into the organic light emitting layer 1333 through the electron transport layer 1334, so that electrons meet holes in the organic light emitting layer 1333, and on the one hand, the increase of the electron injection layer 1335 can improve the efficiency of electron injection into the organic light emitting layer 1333, and on the other hand, it can also reduce the operating voltage.

In some embodiments, referring to fig. 3c, the organic light emitting layer 1333 includes: an organic light emitting bulk layer 13331 and an organic light emitting electron blocking layer 13332, an organic light emitting bulk layer 13331 is laminated between the electron transporting layer 1334 and the hole transporting layer 1332, and an organic light emitting electron blocking layer 13332 is laminated between the organic light emitting bulk layer 13331 and the hole transporting layer 1332.

The organic light emitting body layer 13331 may be configured with a corresponding color of light emitting material to produce a corresponding color of light. For example, in some embodiments, referring to fig. 3d, the organic light emitting body layer 13331 includes multiple color light emitting body layers including a red light emitting body layer 3d1, a green light emitting body layer 3d2, or a blue light emitting body layer 3d 3. Accordingly, in order to block electrons of the corresponding color material, the color electron blocking layer includes a red electron blocking layer 3d4, a green electron blocking layer 3d5, or a blue electron blocking layer 3d 6. The red electron blocking layer 3d4 is opposite to the red light emitting body layer 3d1, the green electron blocking layer 3d5 is opposite to the green light emitting body layer 3d2, and the blue electron blocking layer 3d6 is opposite to the blue light emitting body layer 3d 3.

When an external voltage is applied to the organic light emitting diode device, the red light emitting body layer 3d1 emits red light, and the red electron blocking layer 3d4 blocks red electrons from moving toward the hole transport layer 133. The green light-emitting body layer 3d2 emits green light, and the green electron blocking layer 3d5 blocks the green electrons from moving toward the hole transport layer 1332. The blue light emitting host layer 3d3 emits blue light, and the blue electron blocking layer 3d6 blocks blue electrons from moving toward the hole transport layer 133.

In some embodiments, referring to fig. 4a, the thin film encapsulation layer 14 includes a first inorganic layer 141, and the first inorganic layer 141 is stacked on each OLED device 13. For example, the first inorganic layer 141 is stacked on the cathode 132, and since the first inorganic layer 141 can block moisture or oxygen, and the moisture or oxygen can oxidize the cathode to damage the cathode, the first inorganic layer 141 can protect the cathode, thereby improving the lifespan of the OLED device 13.

In some embodiments, the thickness of the first inorganic layer 141 is smaller than that of the buffer layer 15, that is, the buffer layer 15 is stacked on the side of the first inorganic layer 141 at a height greater than that of the first inorganic layer 141 stacked on the OLED device, so that when folded, the buffer layer 15 can buffer the compressive stress to which the side of the first inorganic layer 141 is entirely subjected, and better protect the first inorganic layer 141 from being directly compressed by the inorganic layer in another adjacent thin film encapsulation layer.

In some embodiments, referring to fig. 4b, the thin film encapsulation layer 14 further includes a first organic layer 142, and the first organic layer 142 is stacked on the first inorganic layer 141 and away from the OLED device 13. The first organic layer 142 can coat the particles and planarize the first inorganic layer 141, so that various structural layers can be more easily stacked in the following process.

In some embodiments, the total thickness of the first organic layer 142 and the first inorganic layer 141 is less than the thickness of the buffer layer 15, that is, the height of the buffer layer 15 stacked on the side surfaces of the first inorganic layer 141 and the first organic layer 142 is greater than the total height of the first inorganic layer 141 and the first organic layer 142 stacked on the OLED device, so that when folded, the buffer layer 15 can buffer the compressive stress on the side surfaces of the first inorganic layer 141 and the first organic layer 142, and the first inorganic layer 141 and the first organic layer 142 are better protected from being directly compressed by another adjacent thin film encapsulation layer.

In some embodiments, referring to fig. 4c, the thin film encapsulation layer 14 further includes a second inorganic layer 143, and the second inorganic layer 143 is stacked on the first organic layer 142 and is away from the first inorganic layer 141. The second inorganic layer 143 can block moisture or oxygen.

In some embodiments, the total thickness of the first organic layer 142, the first inorganic layer 141, and the second inorganic layer 143 is less than the thickness of the buffer layer 15, that is, the height of the buffer layer 15 stacked on the side surfaces of the first inorganic layer 141, the first organic layer 142, and the second inorganic layer 143 is greater than the total height of the first inorganic layer 141, the first organic layer 142, and the second inorganic layer 143 stacked on the OLED device, so that when the OLED device is folded, the buffer layer 15 can buffer the compressive stress of all the side surfaces of the first inorganic layer 141, the first organic layer 142, and the second inorganic layer 143, and better protect the first inorganic layer 141, the first organic layer 142, and the second inorganic layer 143 from being directly compressed by another adjacent thin film encapsulation layer.

In some embodiments, referring to fig. 4d, the thin film encapsulation layer 14 further includes a second organic layer 144, the second organic layer 144 is stacked on the second inorganic layer 143 and away from the first organic layer 142, and the second organic layer 144 can be used for mask patterning.

In some embodiments, the buffer layer 15 may be stacked on the side of the four first inorganic layer 141, the first organic layer 142, the second inorganic layer 143, and the second organic layer 144 to have a height greater than or equal to a total height of the four first inorganic layer 141, the first organic layer 142, the second inorganic layer 143, and the second organic layer 144 stacked on the OLED device.

In some embodiments, the inorganic layers referred to herein may be selected from Al₂O ₃The metal oxide may be selected from silicon nitride, silicon oxide, etc.

The embodiment of the application provides a flexible display device. Referring to fig. 5, the flexible display device 50 includes a housing 51 and a flexible display panel 52, the flexible display panel 52 can be accommodated in the housing 51, for example, the flexible display panel 52 can be retracted in the housing 51, and a user can pull the flexible display panel 52 by hand to pull the flexible display panel 52 out of the housing 51.

In the present embodiment, the flexible display panel 52 may be selected from the flexible display panels illustrated in fig. 1a to 4 d.

In this embodiment, when folding, the film encapsulation layer in the flexible display panel 52 is following when folding, and the buffer layer can prevent that two adjacent film encapsulation layers from directly extruding and colliding each other, cushions the collision of two film encapsulation layers, has reduced the cracked probability of side appears in the film encapsulation layer, and then reduces the side of film encapsulation layer and breaks and make the probability of appearance of the phenomenon that water oxygen got into the OLED device to improve the life of flexible display panel 52 relatively.

Those skilled in the art will appreciate that the processes and materials described in the various embodiments herein are merely exemplary and that the embodiments herein may be used with any processes or materials developed in the future that are suitable for use herein.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; within the context of the present application, where technical features in the above embodiments or in different embodiments can also be combined, the steps can be implemented in any order and there are many other variations of the different aspects of the present application as described above, which are not provided in detail for the sake of brevity; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims

A flexible display panel, comprising:

a thin film transistor substrate including a deposition surface;

a plurality of pixel defining layers sequentially arranged on the deposition surface;

a plurality of OLED devices which are sequentially arranged on the deposition surface, and each OLED device is positioned between every two adjacent pixel defining layers;

each thin film packaging layer is packaged on the corresponding OLED device; and

and the buffer layer is stacked on the side surface of the film packaging layer.
The flexible display panel of claim 1, wherein the buffer layer is laminated between every two adjacent thin film encapsulation layers.
The flexible display panel of claim 1, wherein the buffer layer comprises an organic film layer.
The flexible display panel of claim 1, wherein the thin film encapsulation layer comprises:

a first inorganic layer stacked on each of the OLED devices;

a first organic layer laminated on the first inorganic layer and remote from the OLED device.

A second inorganic layer stacked on the first organic layer and remote from the first inorganic layer.
The flexible display panel of claim 4, wherein the thin film encapsulation layer comprises: a second organic layer stacked on the second inorganic layer and remote from the first organic layer.
The flexible display panel of claim 4, wherein the total thickness of the first organic layer, the first inorganic layer, and the second inorganic layer is less than the thickness of the buffer layer.
The flexible display panel of claim 1, wherein each of the OLED devices comprises:

an anode laminated on a deposition surface of the thin film transistor substrate, wherein the anode is positioned between every two adjacent pixel defining layers;

an organic functional layer stacked on the anode and located between every two adjacent pixel defining layers;

and the cathode is stacked on the organic functional layer and is far away from the anode, and the thin film packaging layer is packaged on the cathode.
The flexible display panel of any one of claims 1 to 7, wherein each of the pixel defining layers comprises:

the third inorganic layer covers the side face of one OLED device in the two adjacent OLED devices of the pixel defining layer;

and the fourth inorganic layer covers the side face of the other OLED device in the two adjacent OLED devices of the pixel defining layer.
The flexible display panel of claim 8, wherein each of the pixel definition layers further comprises:

and the material filling layer is filled between the third inorganic layer and the fourth inorganic layer.
The flexible display panel of claim 8, wherein the third inorganic layer comprises:

the first hook-up part covers a partial area at the top of the material filling layer;

the first extending part is connected with the first hooking part and covers the side face of one OLED device in two adjacent OLED devices of the pixel defining layer.
The flexible display panel of claim 10, wherein the fourth inorganic layer comprises:

the second hook-up part covers a partial area of the top of the material filling layer, and the second hook-up part is opposite to the first hook-up part;

and the second extending part is connected with the second hook-up part and covers the side surface of the other OLED device in the two adjacent OLED devices of the pixel defining layer.
The flexible display panel of claim 11, wherein a side of the buffer layer near the thin film transistor substrate fills a gap between the first raised portion and the second raised portion and abuts against a top of the material filling layer.
The flexible display panel of claim 11, wherein the buffer layer, the first raised portion, and the second raised portion collectively cover the top of the layer of material fill.
A flexible display device, comprising:

a housing; and the number of the first and second groups,

the flexible display panel of any one of claims 1 to 13, receivable within the housing.