Electro-wetting display panel and electro-wetting display device

Abstract

The application discloses an electrowetting display panel and an electrowetting display device, and relates to the technical field of display, wherein the electrowetting display panel comprises a first substrate and a second substrate, an electrode layer, a first insulating layer and a second insulating layer, the first substrate is provided with a plurality of pixel units, the pixel units have a first direction and a second direction which are perpendicular to each other, the pixel units comprise a plurality of sub-pixel units, each of the sub-pixel units extends along the first direction, the electrode layer is arranged on the surface of the first substrate, the first insulating layer is arranged on the surface of the electrode layer, the second insulating layer is arranged on the surface of the second substrate and encloses the first insulating layer to form a plurality of accommodation cavities, the accommodation cavities comprise a receiving bin and a sub-pixel flow channel which are connected in communication, the sub-pixel flow channel is arranged corresponding to the sub-pixel unit, the receiving bin is filled with a liquid, the liquid spreads over the sub-pixel flow channel when the electrode layer is not electrified, and the liquid is accommodated in the receiving bin when the electrode layer is electrified. The technical scheme provided by the application can realize the effect of foldable display.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to an electrowetting display panel and an electrowetting display device. BACKGROUND

[0002] The display principle of the electrowetting electronic paper is that by applying electricity to the liquid drop, the wettability of the solid-liquid interface is changed, thereby controlling the contraction and spreading of the colored ink, and then realizing the switching and gray scale control of the pixel. The electrowetting electronic paper has a wide application prospect due to its advantages of dynamic display, color display, low energy consumption, fast driving speed, high contrast and reflectivity, simple structure and low cost. However, the flexibility of the existing electrowetting electronic paper is relatively poor, and it is difficult to realize the foldable display effect. SUMMARY

[0003] The main purpose of the present application is to provide an electrowetting display panel and an electrowetting display device, which aims to improve the flexibility of the electrowetting display panel and realize the foldable display effect.

[0004] To achieve the above-mentioned purpose, the present application provides an electrowetting display panel, which comprises:

[0005] A first substrate and a second substrate are oppositely arranged, the first substrate is provided with a plurality of pixel units arranged in an array, the pixel units have a first direction and a second direction perpendicular to each other, and the pixel units comprise a plurality of sub-pixel units arranged in an array along the second direction, each of the sub-pixel units extends along the first direction;

[0006] An electrode layer is arranged on the surface of the first substrate facing the second substrate;

[0007] A first insulating layer is arranged on the surface of the electrode layer facing the second substrate; and

[0008] A second insulating layer is arranged on the surface of the second substrate facing the first substrate, and forms a plurality of accommodation cavities spaced along the second direction together with the first insulating layer, each of the accommodation cavities comprises a receiving bin and a sub-pixel flow channel connected in communication, the sub-pixel flow channel corresponds to the sub-pixel unit, the receiving bin is filled with a liquid, the liquid fills the corresponding sub-pixel flow channel when the electrode layer is not powered, and the liquid is received in the corresponding receiving bin when the electrode layer is powered.

[0009] In an embodiment, the electrode layer comprises a plurality of electrode portions, the plurality of electrode portions are arranged on opposite sides of each of the sub-pixel units along the second direction, and each of the electrode portions extends obliquely along the first direction; the distance between the two electrode portions located on opposite sides of the same sub-pixel unit gradually increases in the direction away from the receiving bin.

[0010] In an embodiment, an angle between a length direction of the electrode part and the first direction is A, 0°<A<30°.

[0011] In an embodiment, the liquid is ink, the first insulating layer comprises a first hydrophobic insulating layer and a first hydrophilic insulating layer connected to each other, and the first hydrophilic insulating layer is arranged corresponding to the accommodation cavity.

[0012] The second insulating layer comprises a second hydrophobic insulating layer and a second hydrophilic insulating layer connected to each other, and the second hydrophilic insulating layer is arranged corresponding to the accommodation cavity.

[0013] The first hydrophobic insulating layer and the second hydrophobic insulating layer enclose the sub-pixel flow channel, and the first hydrophilic insulating layer and the second hydrophilic insulating layer enclose the accommodation cavity.

[0014] In an embodiment, the first insulating layer further comprises a third hydrophilic insulating layer, the third hydrophilic insulating layer is arranged corresponding to an end of the sub-pixel flow channel away from the accommodation cavity, and extends along the second direction.

[0015] The second insulating layer further comprises a fourth hydrophilic insulating layer, and the fourth hydrophilic insulating layer is arranged corresponding to the third hydrophilic insulating layer.

[0016] The third hydrophilic insulating layer and the fourth hydrophilic insulating layer are arranged corresponding to the accommodation cavity.

[0017] In an embodiment, the electrowetting display panel further comprises a plurality of support columns, and the plurality of support columns are arranged corresponding to the accommodation cavity and are arranged on opposite sides of each sub-pixel unit along the second direction.

[0018] In an embodiment, the first insulating layer and / or the second insulating layer are provided with a plurality of through holes.

[0019] In an embodiment, the first insulating layer and the second insulating layer are provided with a plurality of through holes on opposite surfaces, and the through holes on the opposite surfaces are distributed in a staggered manner.

[0020] In an embodiment, the electrowetting display panel further comprises a black matrix layer, and the black matrix layer is arranged between the second substrate and the second insulating layer and is arranged corresponding to the sub-pixel units.

[0021] The application further provides an electrowetting display device comprising the electrowetting display panel.

[0022] The electrowetting display panel provided by the present invention includes a first substrate and a second substrate disposed opposite to each other, an electrode layer, a first insulating layer and a second insulating layer. The first substrate is provided with a plurality of pixel units arranged in an array. The pixel units have a first direction and a second direction that are perpendicular to each other. The pixel unit includes a plurality of sub-pixel units spaced apart along the second direction. Each sub-pixel unit extends along the first direction. The electrode layer is disposed on the surface of the first substrate facing the second substrate. The first insulating layer is disposed on the surface of the electrode layer facing the second substrate. The second insulating layer is disposed on the surface of the second substrate facing the first substrate and surrounds the first insulating layer to form a plurality of accommodating cavities spaced apart along the second direction. Each accommodating cavity includes a connected storage compartment and a sub-pixel flow channel. The sub-pixel flow channel is disposed corresponding to the sub-pixel unit. The storage compartment is filled with liquid. When the electrode layer is not energized, the liquid fills the corresponding sub-pixel flow channel. When the electrode layer is energized, the liquid is stored in the corresponding storage compartment. The technical solution provided by this invention employs a single-fluid liquid, which is confined within a cavity. Under the capillary action of the sub-pixel channel, the single-fluid liquid covers the entire sub-pixel channel, achieving normal pixel display. Electrodes are used to control the state of the single-fluid liquid, enabling grayscale display. This single-fluid design effectively avoids uncontrolled liquid stress in the pixel area caused by bending during flexible assembly, achieving grayscale display. It also effectively avoids optical consistency issues caused by interlayer misalignment during bending of dual-fluid systems. Furthermore, the sub-pixel channel design restricts the liquid's movement trajectory during bending to within the sub-pixel channel. This constraint ensures that the liquid's positional change is only related to the electrodes, eliminating the need for compensation voltage or other compensation mechanisms during bending. This simplifies the design complexity of the driving system, improves the flexibility of the electrowetting display panel, and enables foldable displays. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0024] Figure 1 This is a top view schematic diagram of a partial structure of an embodiment of the electrowetting display panel provided by the present invention;

[0025] Figure 2 for Figure 1 A structural schematic diagram from another perspective after a cross-section at point AA along the middle edge;

[0026] Figure 3 for Figure 1 A structural schematic diagram from another perspective after cross-section at point BB;

[0027] Figure 4 For Figure 1 A schematic diagram of the electro wetting display panel when the electrodes are not powered.

[0028] BRIEF DESCRIPTION OF DRAWINGS

[0029] 100, electro wetting display panel; 1, first substrate; 2, electrode layer; 21, electrode part; 3, first insulating layer; 31, first hydrophobic insulating layer; 32, first hydrophilic insulating layer; 33, third hydrophilic insulating layer; 34, through hole; 4, second insulating layer; 41, second hydrophobic insulating layer; 42, second hydrophilic insulating layer; 43, fourth hydrophilic insulating layer; 5, accommodating cavity; 51, storage bin; 52, sub-pixel flow channel; 6, pixel wall; 61, pixel unit; 611, sub-pixel unit; 7, ink; 71, red ink; 72, green ink; 73, blue ink; 8, support column; 9, second substrate; 10, black matrix layer; 100a, first direction; 100b, second direction; 100c, third direction.

[0030] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0032] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between the components in a certain posture, and if the certain posture changes, the directional indications will also change accordingly.

[0033] In addition, if the description of "first", "second" and the like is involved in the embodiments of the present application, the description of "first", "second" and the like is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In addition, if "and / or" or "and / or" appears throughout the text, it means that the three parallel schemes include the A scheme, or the B scheme, or the A and B schemes. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0034] The display principle of electrowetting electronic paper is: by adding electricity to the droplet, changing the wettability of the solid-liquid interface, thereby controlling the contraction and spreading of the color ink, and then realizing the switching and gray scale control of the pixel. Electrowetting electronic paper has a wide application prospect because of its dynamic display, color display, low energy consumption, fast driving speed, high contrast and reflectivity, simple structure, low cost and other advantages.

[0035] The existing electrowetting electronic paper usually includes a lower array substrate, a lower electrode layer, a hydrophobic insulating layer, a pixel layer, an upper electrode layer and an upper array substrate which are sequentially stacked, the pixel layer includes a plurality of pixel units enclosed by a pixel wall and two kinds of fluids, non-polar fluid (such as color ink) and polar fluid (such as water) arranged in the pixel unit, when the upper electrode layer and the lower electrode layer are not electrified, the color ink spreads over the entire pixel unit, and the pixel unit displays the color of the ink, after the upper electrode layer and the lower electrode layer are electrified, the color ink is pushed away by the water, and the movement of the oil-water interface can be controlled by the applied electric field intensity, realizing the gray scale control.

[0036] For flexibility, the existing electrowetting electronic paper has the following reasons for being difficult to realize flexibility: (1) The gray scale of electrowetting display is realized by adjusting the ink opening rate through voltage, and the bending caused by flexibility will cause uneven stress in the pixel area, change the contact angle of the ink and the substrate, destroy the wettability balance of the solid-liquid interface, and thus cause the opening rate to deviate from the preset value, affecting the reflectivity and gray scale accuracy; in addition, the interlayer misregistration may occur when the double fluid layer is bent, which destroys the optical consistency. (2) The existing driving method is designed based on the flat state, without considering the local deformation difference caused by bending. Usually, the pixels in the bending area need to dynamically adjust the driving voltage to compensate for the deviation of the ink shrinkage rate, and thus ensure the display effect, but there is a lack of real-time deformation detection and compensation means in actual engineering. (3) The insulating layer is prone to micro-cracks when repeatedly bent, which causes the insulating layer to break or the insulating layer to fail, and thus causes the problems of electric leakage or electrochemical aging.

[0037] Based on at least one of the above reasons, the present application provides an electrowetting display panel, aiming to improve the flexibility of the electrowetting display panel and realize the effect of foldable display.

[0038] Please refer to Figures 1 to 4 In an embodiment of the present application, the electrowetting display panel 100 provided by the present application comprises a first substrate 1 and a second substrate 9 arranged oppositely, an electrode layer 2, a first insulating layer 3 and a second insulating layer 4, the first substrate 1 is provided with a plurality of pixel units 61 arranged in an array, the pixel units 61 have a first direction 100a and a second direction 100b perpendicular to each other, the pixel units 61 comprise a plurality of sub-pixel units 611 arranged in an array along the second direction 100b, each of the sub-pixel units 611 extends along the first direction 100a; the electrode layer 2 is arranged on the surface of the first substrate 1 facing the second substrate 9; the first insulating layer 3 is arranged on the surface of the electrode layer 2 facing the second substrate 9; the second insulating layer 4 is arranged on the surface of the second substrate 9 facing the first substrate 1, and forms a plurality of accommodation cavities 5 spaced along the second direction 100b together with the first insulating layer 3, each of the accommodation cavities 5 comprises a receiving bin 51 and a sub-pixel flow channel 52 connected in communication, the sub-pixel flow channel 52 is arranged corresponding to the sub-pixel unit 611, the receiving bin 51 is filled with a liquid, the liquid fills the corresponding sub-pixel flow channel 52 when the electrode layer 2 is not powered, and the liquid is accommodated in the corresponding receiving bin 51 when the electrode layer 2 is powered.

[0039] Specifically, the first substrate 1 is an array substrate, comprising a substrate and a driving circuit layer, wherein the substrate is a transparent substrate, which can be transparent glass, and the driving circuit layer can be a thin film transistor array layer, the specific structure of which can refer to the prior art, and will not be described here. The first substrate 1 is provided with a pixel wall 6, which encloses a plurality of array distributed pixel units 61, which can be square structures, having a first direction 100a and a second direction 100b perpendicular to each other, the pixel unit 61 comprising a plurality of sub-pixel units 611 spaced apart, the sub-pixel unit 611 being long strip-shaped, the length direction of which extends along the first direction 100a, i.e. the first direction 100a is the length direction of the sub-pixel unit 611, the second direction 100b is the width direction of the sub-pixel unit 611, and a plurality of sub-pixel units 611 are spaced apart along the second direction 100b. Optionally, the number of sub-pixel units 611 is three, which are red sub-pixel units, green sub-pixel units and blue sub-pixel units. The electrode layer 2 is a transparent electrode layer, the material composition of which is not limited. The electrode layer 2 is located in the pixel unit 61 of the first substrate 1 and is the driving source of the electrowetting effect, used for driving the morphological change of the electrowetting liquid. The first insulating layer 3 is provided on the electrode layer 2 and plays an insulating protection role, and at the same time serves as a contact interface of the liquid, the surface properties of which directly affect the electrowetting effect. The second substrate 9 is a transparent substrate, which can be transparent glass, and is arranged opposite to the first substrate 1. The second insulating layer 4 is arranged on the inner surface of the second substrate 9 and encloses a plurality of accommodation cavities 5 spaced apart along the second direction 100b with the first insulating layer 3, the accommodation cavity 5 comprising a receiving bin 51 and a sub-pixel flow channel 52 connected thereto, the sub-pixel flow channel 52 being arranged corresponding to the sub-pixel unit 611, when the sub-pixel unit 611 is arranged as three, the sub-pixel flow channel 52 is also arranged as three, and the projection size of the sub-pixel flow channel 52 on the first substrate 1 is matched with the projection size of the sub-pixel unit 611 on the first substrate 1. The receiving bin 51 is arranged corresponding to the interval between the sub-pixel unit 611 and the pixel wall 6, and the receiving bin 51 is filled with a liquid, which can be a dielectric ink 7 or a solution containing charged pigment particles, which is not limited here. The size of the receiving bin 51 along the second direction 100b is greater than the size of the sub-pixel unit 611 along the second direction 100b, and the specific size of the receiving bin 51 is determined according to the actual situation, so that the liquid can be completely received in the receiving bin 51, and at the same time it is also guaranteed that the liquid can be completely spread when it is unfolded. When the electrode layer 2 is not electrified, the liquid is unfolded and spreads completely in the sub-pixel flow channel 52 under the capillary force of the sub-pixel flow channel 52, at this time the sub-pixel presents the color of the corresponding liquid, realizing normal display of the sub-pixel. When the sub-pixel flow channel 52 is arranged as three, the three sub-pixel flow channels 52 are filled with red ink 71, green ink 72 and blue ink 73 respectively, at this time color display can be realized.After the electrode layer 2 is powered on, the liquid is controlled to move towards the direction close to the storage bin 51 under the electric field of the electrode, so as to realize the gray scale control of the pixel; when the liquid is completely stored in the storage bin 51, the sub-pixel displays the color of the bottom layer.

[0040] It should be noted that the first substrate 1 is deposited with a reflective layer, and when the liquid is completely stored in the storage bin 51, the sub-pixel displays the color of the reflective layer. The reflective layer can be white, and at this time, the sub-pixel displays white.

[0041] After the electrode layer 2 is powered on, the liquid is mainly guided by the electric field gradient distribution of the electrode layer 2 to guide the direction of the liquid force, so as to realize the movement of the liquid towards the direction close to the storage layer. In some embodiments, the thickness of the electrode layer 2 gradually decreases along the direction away from the storage bin 51, and under the same voltage, the electric field strength of the area with larger electrode thickness is higher, so that the liquid moves to the area with high electric field strength, that is, moves towards the direction close to the storage bin 51. Of course, in other embodiments, the electrode layer 2 can also be provided in other structures, as long as it can drive the liquid to move towards the direction close to the storage bin 51.

[0042] In the technical solution provided by the application, a liquid single fluid is used, and the liquid single fluid is constrained in the accommodation cavity 5. Under the capillary action of the sub-pixel flow channel 52, the liquid single fluid covers the entire sub-pixel flow channel 52, so as to realize that the pixel presents the color of the liquid; and the existence state of the liquid single fluid is controlled by the electrode, so as to realize the gray scale display of the pixel.

[0043] The liquid single fluid design adopted by the application can effectively avoid the loss of control of the liquid force in the pixel area caused by the bending of the flexible display, realize the gray scale display of the pixel, and effectively avoid the optical consistency problem caused by the layer misalignment of the double fluid when bending. In addition, the sub-pixel flow channel 52 design limits the movement track of the liquid within the sub-pixel flow channel 52 when the liquid is bent. This constraint makes the position change of the liquid only related to the electrode, that is, there is no need to consider the compensation voltage or other compensation mechanisms when bending, which simplifies the design complexity of the driving system and is conducive to improving the flexibility of the electrowetting display panel 100 and realizing the foldable display effect.

[0044] Please refer to Figure 1 and Figure 4 In optional embodiments of the application, the electrode layer 2 includes a plurality of electrode portions 21, the plurality of electrode portions 21 are spaced apart on opposite sides of each sub-pixel unit 611 along the second direction 100b, and each electrode portion 21 extends obliquely along the first direction 100a; the spacing between the two electrode portions 21 located on opposite sides of the same sub-pixel unit 611 gradually increases along the direction away from the storage bin 51.

[0045] Specifically, the electrode part 21 is arranged in a strip shape and extends obliquely along the first direction 100a, and each sub-pixel unit 611 is provided with one electrode part 21 on each of the opposite sides along the second direction 100b, that is, one sub-pixel unit 611 corresponds to a group of electrode parts 21, and the spacing between the two electrode parts 21 corresponding to the same sub-pixel unit 611 is different, and the spacing gradually increases in the direction away from the storage bin 51, and the electric field strength generated by the electrode part 21 after being powered on will increase with the decrease of the spacing, so that the electric field strength in the area close to the storage bin 51 is larger, and the electric field strength in the area away from the storage bin 51 is smaller. Thus, under the action of dielectric force, the fluid moves towards the direction close to the storage bin 51 and is finally stored in the storage bin 51.

[0046] The embodiment of the present application adopts a pair of asymmetrically spaced electrode parts 21 to drive the movement of the liquid in the sub-pixel flow channel 52, which has a simple structure and is easy to drive.

[0047] In some embodiments of the present application, the electrode part 21 is driven by an alternating current power supply, and the voltage size and frequency depend on the fluid characteristics and the required gray scale. When an alternating voltage is applied, a non-uniform electric field is generated between the two electrode parts 21 located on both sides of the sub-pixel flow channel 52, and when the dielectric liquid is subjected to the action of the non-uniform electric field, the dielectric liquid tends to gather in the area with high electric field strength, thus realizing liquid movement and achieving the purpose of gray scale control.

[0048] In an optional embodiment of the present application, the angle between the length direction of the electrode part 21 and the first direction 100a is defined as A, and 0°<A<30°.

[0049] The embodiment of the present application limits the inclination angle of the electrode part 21 within the above range, which can make the electric field lines form a continuous and uniform gradient distribution in the direction from the end of the sub-pixel unit 611 to the storage bin 51, ensure that the dielectric force acting on the liquid always points to the storage bin 51, and improve the stability of liquid movement; at the same time, it can also effectively enhance the efficiency of driving force, improve the response speed, improve the linearity of gray scale control, improve the accuracy of gray scale control, adapt to flexible bending scenarios, and ensure the consistency of gray scale display in flexible scenarios.

[0050] Please refer to Figures 1 to 4 In an optional embodiment of the present application, the liquid is ink 7, the first insulating layer 3 includes a first hydrophobic insulating layer 31 and a first hydrophilic insulating layer 32 connected with each other, and the first hydrophilic insulating layer 32 is arranged corresponding to the storage bin 51; the second insulating layer 4 includes a second hydrophobic insulating layer 41 and a second hydrophilic insulating layer 42 connected with each other, and the second hydrophilic insulating layer 42 is arranged corresponding to the storage bin 51; the first hydrophobic insulating layer 31 and the second hydrophobic insulating layer 41 enclose to form the sub-pixel flow channel 52, and the first hydrophilic insulating layer 32 and the second hydrophilic insulating layer 42 enclose to form the storage bin 51.

[0051] Specifically, the liquid is ink 7, which can be color ink. When the sub-pixel unit 611 is provided as three, the color ink 7 includes red ink 71, green ink 72 and blue ink 73, which are filled in the three sub-pixel flow channels 52, respectively. The first insulating layer 3 includes a first hydrophobic insulating layer 31 and a first hydrophilic insulating layer 32. The first hydrophobic insulating layer 31 corresponds to the area outside the receiving bin 51, and the first hydrophilic insulating layer 32 is provided corresponding to the receiving bin 51. It should be noted that, in order to make the receiving bin 51 accommodate enough ink 7, and the ink 7 can fully spread on the corresponding sub-pixel flow channel 52 when it is spread, in the design, the size of the receiving bin 51 along the third direction 100c (i.e. the thickness direction) is greater than the size of the corresponding sub-pixel flow channel 52 along the third direction 100c (i.e. the thickness direction), that is, the size of the first hydrophilic insulating layer 32 along the third direction 100c (i.e. the thickness direction) is less than the size of the first hydrophobic insulating layer 31 along the third direction 100c (i.e. the thickness direction). The first hydrophilic insulating layer 32 can be provided through the first hydrophobic insulating layer 31 towards the side of the first substrate 1, of course, it can also not be provided through the first hydrophobic insulating layer 31 towards the side of the first substrate 1, which is not limited herein. The second insulating layer 4 also includes a second hydrophobic insulating layer 41 and a second hydrophilic insulating layer 42. The second hydrophobic insulating layer 41 is provided corresponding to the first hydrophobic insulating layer 31, and both are provided corresponding to the area outside the receiving bin 51, so that they can be enclosed to form a plurality of spaced sub-pixel flow channels 52, and the distal ends of the adjacent two sub-pixel flow channels 52 away from the receiving bin 51 are not communicated with each other. The second hydrophilic insulating layer 42 and the second hydrophilic insulating layer 42 are provided corresponding to each other, and both are provided corresponding to the receiving bin 51, and the two are enclosed to form a plurality of spaced receiving bins 51.

[0052] When the electrode layer 2 is not powered, the color ink in the receiving bin 51 will spread on the corresponding sub-pixel flow channel 52 under the surface tension of the hydrophobic insulating layer (including the first hydrophobic insulating layer 31 and the second hydrophobic insulating layer 41) and the capillary action of the sub-pixel flow channel 52. At this time, the sub-pixel will show the color of the color ink. When the sub-pixel flow channel 52 is provided as three and is filled with red ink 71, green ink 72 and blue ink 73, respectively, the entire pixel unit 61 realizes color display.

[0053] The embodiment of the present application can ensure that the ink 7 can naturally and uniformly spread on the sub-pixel flow channel 52 under the surface tension and the capillary action of the sub-pixel flow channel 52 by reasonably designing the surface properties (such as hydrophobicity) of the first insulating layer 3 and the second insulating layer 4.

[0054] Please refer to Figures 1 to 4In the optional embodiment of the present application, the first insulating layer 3 further comprises a third hydrophilic insulating layer 33, which is arranged at the end of the sub-pixel flow channel 52 away from the accommodation cavity 51 and extends along the second direction 100b; the second insulating layer 4 further comprises a fourth hydrophilic insulating layer 43, which is arranged corresponding to the third hydrophilic insulating layer 33; the adjacent two sub-pixel flow channels 52 are communicated through the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43.

[0055] Specifically, the first insulating layer 3 comprises a first hydrophobic insulating layer 31, a first hydrophilic insulating layer 32 and a third hydrophilic insulating layer 33, the first hydrophilic insulating layer 32 is arranged corresponding to the accommodation cavity 51, and the third hydrophilic insulating layer 33 is arranged at the end of the sub-pixel flow channel away from the accommodation cavity 51 and extends along the second direction 100b; correspondingly, the specific structure of the second insulating layer 4 is arranged corresponding to the specific structure of the first insulating layer 3, so that the end of the adjacent two sub-pixel flow channels 52 away from the accommodation cavity 51 is communicated through the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43, which can better balance the air pressure and facilitate the flow of ink 7 in the sub-pixel flow channel 52. Moreover, since the third hydrophilic insulating layer 33 and the first hydrophobic insulating layer 31 both correspond to the sub-pixel flow channel 52, in the third direction 100c (i.e. the thickness direction), the surface of the third hydrophilic insulating layer 33 facing the sub-pixel flow channel 52 is flush with the surface of the first hydrophobic insulating layer 31 facing the sub-pixel flow channel 52, and the thickness of the third hydrophilic insulating layer 33 can be the same as or different from the thickness of the first hydrophobic insulating layer 31, which is not limited herein. Since the adjacent two accommodation cavities 51 are not communicated with each other, i.e. the plurality of first hydrophilic insulating layers 32 are arranged at intervals along the second direction 100b, the ink 7 in the accommodation cavity 51 flows away from the accommodation cavity 51 under the capillary action of the sub-pixel flow channel 52 and the surface tension of the first hydrophobic insulating layer 31, and when it flows to the third hydrophilic insulating layer 33, the ink 7 stops moving due to the change of wetting gradient (i.e. from a hydrophobic surface to a hydrophilic surface). Therefore, the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43 constitute an ink 7 stopping structure, and the ink 7 eventually spreads over the entire sub-pixel flow channel 52.

[0056] Optionally, the size (i.e. width) of the third hydrophilic insulating layer 33 along the first direction 100a is 5-20 μm, such as 5 μm, 10 μm, 15 μm, 20 μm and any interval value between any two endpoint values. Such design can better balance the air pressure and facilitate the flow of ink 7 in the sub-pixel flow channel 52.

[0057] Please refer to Figure 1 , Figure 3 and Figure 4In an optional embodiment of the present application, the electrowetting display panel 100 further comprises a plurality of support columns 8, which are arranged at opposite sides of each sub-pixel unit 611 along the second direction 100b and between the first insulating layer 3 and the second insulating layer 4.

[0058] In the embodiment of the present application, the support columns 8 are located between the first insulating layer 3 and the second insulating layer 4 and at intervals of the sub-pixel flow channels 52, thereby supporting the sub-pixel flow channels 52. When the pixel unit 61 is bent, the plurality of support columns 8 are arranged at intervals, thereby ensuring the uniformity of the intervals of the sub-pixel flow channels 52 and further ensuring the accuracy of the gray scale control. In addition, the support columns 8 can enhance the structural strength of the entire electrowetting display panel 100, reduce the fatigue damage of the substrate and the insulating layer caused by long-term folding and bending, and prolong the service life of the display panel.

[0059] The cross-sectional outer contour shape of the support column 8 can be circular, polygonal or other reasonable shape, and the material includes but is not limited to at least one of photoresist, transparent resin, inorganic oxide, and metal oxide composite material, which is not limited herein.

[0060] Please refer again to Figure 2 In the optional embodiment of the present application, the first insulating layer 3 and / or the second insulating layer 4 is / are arranged at intervals with a plurality of through holes 34.

[0061] In the embodiment of the present application, the first insulating layer 3 and / or the second insulating layer 4 is / are designed with a hole structure, which can effectively avoid or reduce the probability of micro-cracks of the insulating layer when bending, thereby making the electrowetting display panel 100 conducive to realizing the effect of foldable display.

[0062] Specifically, the first hydrophobic insulating layer 31 of the first insulating layer 3 and / or the second hydrophobic insulating layer 41 of the second insulating layer 4 is / are designed with a hole structure. Preferably, the first insulating layer 3 and the second insulating layer 4 are both arranged at intervals with a plurality of through holes 34. The shape and size of the through hole 34 are not limited herein.

[0063] It should be noted that the essential reason for the micro-cracks of the insulating layer when bending is that the degree of deformation in the bending outer side direction exceeds the maximum tensile amount of the material. Reducing the thickness of the material can alleviate this problem to a certain extent, but reducing the thickness of the insulating layer can easily cause the resistance of the insulating layer to decrease, thereby affecting the performance of the pixel due to the electric leakage. The embodiment of the present application reduces the thickness of the insulating layer by designing the first insulating layer 3 and / or the second insulating layer 4 with a hole structure, without reducing the insulating performance, thereby improving the bending resistance of the first insulating layer 3 and / or the second insulating layer 4.

[0064] Please refer again to Figure 2In an optional embodiment of the present application, the first insulating layer 3 and the second insulating layer 4 are both provided with a plurality of through holes 34 on opposite surfaces thereof, and the through holes 34 on the opposite surfaces are distributed in a staggered manner.

[0065] In an embodiment of the present application, the first hydrophobic insulating layer 31 of the first insulating layer 3 and the second hydrophobic insulating layer 41 of the second insulating layer 4 are both designed with a plurality of through holes 34 on opposite surfaces thereof, and the through holes 34 on the opposite surfaces are distributed in a staggered manner. Such a design can more effectively avoid or reduce the probability of micro-cracks of the insulating layer during bending, so as to make the electrowetting display panel 100 more conducive to realizing the effect of foldable display. Moreover, the above structural design can also effectively reduce the flow hysteresis rate and improve the driving performance.

[0066] Please refer again to Figure 1 and Figure 3 In an optional embodiment of the present application, the electrowetting display panel 100 further comprises a black matrix layer 10, which is arranged between the second substrate 9 and the second insulating layer 4 and is arranged in a spaced manner corresponding to the sub-pixel units 611.

[0067] In an embodiment of the present application, the black matrix layer 10 is arranged in a spaced manner corresponding to the sub-pixel units 611, which serves to divide each sub-pixel unit 611 to prevent light mixing and color mixing. The black matrix layer 10 is formed by a black opaque layer, and the specific material composition thereof is not limited herein.

[0068] The present application further provides an electrowetting display device, which comprises the electrowetting display panel 100. The specific structure of the electrowetting display panel 100 is referred to the above embodiments. Since the electrowetting display device adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated herein. The electrowetting display device can be an electrowetting electronic paper.

[0069] Since the electrowetting display panel 100 of the present application adopts a liquid single-fluid design, it can effectively avoid the stress loss of control of the liquid in the pixel area caused by bending during the flexible display, realize the pixel gray scale display, and effectively avoid the optical consistency problem caused by the interlayer misalignment during the bending of the double-fluid, and the sub-pixel flow channel 52 design limits the movement track of the liquid within the sub-pixel flow channel 52 during the bending. Such a constraint makes the position change of the liquid only related to the electrode, i.e. without considering the compensation voltage or other compensation mechanisms during the bending, which simplifies the design complexity of the driving system and is conducive to improving the flexibility of the electrowetting display panel 100 and realizing the effect of foldable display. That is, the electrowetting electronic paper provided by the present application is a foldable electrowetting electronic paper.

[0070] The above merely illustrates the embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structural transformation, direct / indirect application in other related technical fields, or the like, within the technical concept of the present application, and based on the content of the present application and the accompanying drawings, are included in the patent protection scope of the present application.

Claims

1. An electrowetting display panel, characterized in that, The display panel comprises: a first substrate and a second substrate arranged oppositely, the first substrate is provided with a plurality of pixel units arranged in an array, the pixel units have a first direction and a second direction perpendicular to each other, and each of the pixel units comprises a plurality of sub-pixel units arranged in an array along the second direction and extending along the first direction; an electrode layer arranged on a surface of the first substrate facing the second substrate; a first insulating layer arranged on a surface of the electrode layer facing the second substrate; and a second insulating layer arranged on a surface of the second substrate facing the first substrate and enclosing the first insulating layer to form a plurality of accommodating cavities arranged in an array along the second direction, each of the accommodating cavities comprises a receiving chamber and a sub-pixel flow channel connected to each other, the sub-pixel flow channel is arranged corresponding to the sub-pixel unit, the receiving chamber is filled with a liquid, the liquid fills the corresponding sub-pixel flow channel when the electrode layer is not powered, and the liquid is received in the corresponding receiving chamber when the electrode layer is powered. The electrode layer comprises a plurality of electrode portions arranged in an array on opposite sides of each of the sub-pixel units along the second direction, and each of the electrode portions extends obliquely along the first direction.

2. The electrowetting display panel of claim 1, wherein, The distance between two electrode portions arranged on opposite sides of the same sub-pixel unit gradually increases in a direction away from the receiving chamber. An angle between a length direction of the electrode portion and the first direction is defined as A, and 0° < A < 30°.

3. The electrowetting display panel of claim 2, wherein, The liquid is ink, the first insulating layer comprises a first hydrophobic insulating layer and a first hydrophilic insulating layer connected to each other, and the first hydrophilic insulating layer is arranged corresponding to the receiving chamber. 4.The electrowetting display panel of claim 1, wherein, The second insulating layer comprises a second hydrophobic insulating layer and a second hydrophilic insulating layer connected to each other, and the second hydrophilic insulating layer is arranged corresponding to the receiving chamber. The first hydrophobic insulating layer and the second hydrophobic insulating layer enclose the sub-pixel flow channel, and the first hydrophilic insulating layer and the second hydrophilic insulating layer enclose the receiving chamber. The first insulating layer further comprises a third hydrophilic insulating layer arranged corresponding to an end of the sub-pixel flow channel away from the receiving chamber and extending along the second direction.

5. The electrowetting display panel of claim 4, wherein, The second insulating layer further comprises a fourth hydrophilic insulating layer arranged corresponding to the third hydrophilic insulating layer. Two adjacent sub-pixel flow channels are connected to each other through the third hydrophilic insulating layer and the fourth hydrophilic insulating layer. The electrowetting display panel further comprises a plurality of support columns arranged in an array on opposite sides of each of the sub-pixel units along the second direction and between the first insulating layer and the second insulating layer.

6. The electrowetting display panel of any one of claims 1 to 5, wherein, The first insulating layer and / or the second insulating layer is / are provided with a plurality of through holes arranged in an array.

7. The electrowetting display panel of any one of claims 1 to 5, wherein, The first insulating layer and the second insulating layer are provided with a plurality of through holes arranged in an array on opposite surfaces thereof, and the through holes arranged on the opposite surfaces are arranged in a staggered manner.

8. The electrowetting display panel of claim 7, wherein, The electrowetting display panel further comprises a black matrix layer arranged between the second substrate and the second insulating layer and corresponding to the sub-pixel units arranged in an array.

9. The electrowetting display panel of any one of claims 1 to 5, wherein, ​ 10. An electrowetting display device, characterized in that An electrowetting display panel comprising any one of claims 1 to 9. An electrowetting display panel comprising any one of claims 1 to 9.

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