Electrowetting display panel and electrowetting display device

Abstract

The invention discloses an electrowetting display panel and an electrowetting display device, and relates to the technical field of display, the electrowetting display panel comprises a first substrate, 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, each pixel unit has a first direction and a second direction which are perpendicular to each other, and the second substrate is provided with a plurality of second insulating layers; the pixel unit comprises a plurality of sub-pixel units, and each sub-pixel unit extends in 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, the second insulating layer and the first insulating layer define a plurality of containing cavities, each containing cavity comprises a containing bin and a sub-pixel flow channel which are communicated, the sub-pixel flow channels are arranged corresponding to the sub-pixel units, the containing bins are filled with liquid, the sub-pixel flow channels are fully paved with the liquid when the electrode layer is not powered on, and the sub-pixel flow channels are communicated with the containing bins. And when the electrode layer is electrified, the electrode layer is accommodated in the accommodating bin. According to the technical scheme, the foldable display effect can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an electrowetting display panel and an electrowetting display device. Background Art

[0002] The display principle of electrowetting e-paper is to apply electricity to liquid droplets, changing the wettability of the solid-liquid interface, thereby controlling the shrinkage and spread of colored inks, thereby achieving pixel switching and grayscale adjustment. Electrowetting e-paper has broad application prospects due to its advantages such as dynamic and color display, low energy consumption, fast driving speed, high contrast and reflectivity, simple structure, and low cost. However, existing electrowetting e-paper has relatively poor flexibility, making it difficult to achieve foldable displays. Summary of the Invention

[0003] The main purpose of the present invention is to provide an electrowetting display panel and an electrowetting display device, aiming to improve the flexibility of the electrowetting display panel and achieve a foldable display effect.

[0004] To achieve the above objectives, the present invention provides an electrowetting display panel, comprising: A first substrate and a second substrate are disposed opposite to each other, the first substrate being provided with a plurality of pixel units distributed in an array, the pixel units having a first direction and a second direction perpendicular to each other, the pixel units including a plurality of sub-pixel units spaced apart along the second direction, each of the sub-pixel units extending along the first direction; an electrode layer, disposed on a surface of the first substrate facing the second substrate; a first insulating layer, disposed on a surface of the electrode layer facing the second substrate; and A second insulating layer is arranged on the surface of the second substrate facing the first substrate, and is enclosed with the first insulating layer to form a plurality of accommodating cavities spaced along the second direction, each of the accommodating cavities includes a connected storage bin and a sub-pixel flow channel, the sub-pixel flow channel is arranged corresponding to the sub-pixel unit, the storage bin is filled with liquid, the liquid covers the corresponding sub-pixel flow channel when the electrode layer is not energized, and the liquid is stored in the corresponding storage bin when the electrode layer is energized.

[0005] In one embodiment, the electrode layer includes a plurality of electrode portions, and the plurality of electrode portions are spaced apart along the second direction on opposite sides of each sub-pixel unit, and each of the electrode portions extends obliquely along the first direction; the spacing between two electrode portions located on opposite sides of the same sub-pixel unit gradually increases in the direction away from the storage bin.

[0006] In one embodiment, an angle between the length direction of the electrode portion and the first direction is defined as A, and 0°<A<30°.

[0007] In one embodiment, the liquid is ink, the first insulating layer includes a first hydrophobic insulating layer and a first hydrophilic insulating layer connected to each other, and the first hydrophilic insulating layer is provided corresponding to the receiving compartment; The second insulating layer includes a second hydrophobic insulating layer and a second hydrophilic insulating layer connected to each other, and the second hydrophilic insulating layer is provided corresponding to the storage compartment; The first hydrophobic insulating layer and the second hydrophobic insulating layer together form the sub-pixel flow channel, and the first hydrophilic insulating layer and the second hydrophilic insulating layer together form the storage compartment.

[0008] In one embodiment, the first insulating layer further includes a third hydrophilic insulating layer, the third hydrophilic insulating layer being provided corresponding to an end of the sub-pixel flow channel away from the receiving compartment and extending along the second direction; The second insulating layer further includes a fourth hydrophilic insulating layer, and the fourth hydrophilic insulating layer is arranged corresponding to the third hydrophilic insulating layer; Two adjacent sub-pixel flow channels are connected through the third hydrophilic insulating layer and the fourth hydrophilic insulating layer.

[0009] In one embodiment, the electrowetting display panel further includes a plurality of support columns, which are spaced apart along the first direction at opposite sides of each sub-pixel unit along the second direction and are located between the first insulating layer and the second insulating layer.

[0010] In one embodiment, a plurality of through holes are provided at intervals in the first insulating layer and / or the second insulating layer.

[0011] In one embodiment, a plurality of through holes are spaced apart on opposite surfaces of the first insulating layer and the second insulating layer, and the plurality of through holes on the opposite surfaces are staggered.

[0012] In one embodiment, the electrowetting display panel further includes a black matrix layer, and the black matrix layer is disposed between the second substrate and the second insulating layer and is arranged corresponding to the intervals of the sub-pixel units.

[0013] The present invention also provides an electrowetting display device, comprising the electrowetting display panel as described above.

[0014] The electrowetting display panel provided by the present invention includes a first substrate and a second substrate arranged 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 distributed in an array, the pixel units have a first direction and a second direction perpendicular to each other, the pixel units include a plurality of sub-pixel units spaced apart along the second direction, and each sub-pixel unit extends along the first direction; the electrode layer is arranged on the surface of the first substrate facing the second substrate; the first insulating layer is arranged on the surface of the electrode layer facing the second substrate; the second insulating layer is arranged on the surface of the second substrate facing the first substrate, and is enclosed with the first insulating layer to form a plurality of accommodating cavities spaced apart along the second direction, each accommodating cavity includes a connected storage bin and a sub-pixel flow channel, the sub-pixel flow channel is arranged corresponding to the sub-pixel unit, the storage bin is filled with liquid, the liquid covers the corresponding sub-pixel flow channel when the electrode layer is not energized, and the liquid is stored in the corresponding storage bin when the electrode layer is energized. In the technical solution provided by the present invention, a liquid single fluid is adopted and the liquid single fluid is constrained in the accommodating cavity. Under the capillary action of the sub-pixel flow channel, the liquid single fluid spreads over the entire sub-pixel flow channel to achieve normal pixel display; and the existence state of the liquid single fluid is controlled by the electrode to achieve pixel grayscale display. The present invention adopts a liquid single fluid design, which can effectively avoid the bending caused by flexibility, which causes the liquid in the pixel area to be uncontrolled by force, thereby achieving pixel grayscale display. At the same time, it can also effectively avoid the optical consistency problem caused by the interlayer dislocation when the two fluids are bent. In addition, the sub-pixel flow channel design is adopted, so that the movement trajectory of the liquid during bending is limited to the range of the sub-pixel flow channel. This constraint effect 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 mechanism during bending, which simplifies the design complexity of the driving system, is conducive to improving the flexibility of the electrowetting display panel, and achieves the effect of foldable display. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0016] Figure 1 A schematic top view of a portion of the structure of an embodiment of an electrowetting display panel provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the structure from another perspective after sectioning along the middle line AA; Figure 3 for Figure 1 A schematic diagram of the structure from another perspective after sectioning along the middle edge BB; Figure 4 for Figure 1 Schematic diagram of the electrowetting display panel when the electrodes are not energized.

[0017] Description of Figure Numbers: 100. Electrowetting display panel; 1. First substrate; 2. Electrode layer; 21. Electrode portion; 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 compartment; 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.

[0018] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0021] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] The display principle of electrowetting electronic paper is to apply electricity to liquid droplets, changing the wettability of the solid-liquid interface. This controls the shrinkage and spread of colored ink, enabling pixel switching and grayscale modulation. Electrowetting electronic paper has broad application prospects due to its advantages, including dynamic and color display, low energy consumption, fast driving speed, high contrast and reflectivity, simple structure, and low cost.

[0023] 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 stacked in sequence. The pixel layer includes multiple pixel units formed by pixel walls and two fluids: a non-polar fluid (such as colored ink) and a polar fluid (such as water) located in the pixel units. When the upper electrode layer and the lower electrode layer are not energized, the colored ink covers 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 energized, the colored ink is pushed away by the water. The applied electric field strength can be used to control the movement of the oil-water interface to achieve grayscale regulation.

[0024] As for flexibility, the main reasons why existing electrowetting electronic paper is difficult to achieve flexibility are as follows: (1) The grayscale of electrowetting display is achieved by voltage-controlled ink aperture ratio, and the bending caused by flexibility will cause uneven force on the pixel area, change the contact angle between the ink and the substrate, and destroy the wettability balance of the solid-liquid interface, thereby causing the aperture ratio to deviate from the preset value, affecting the reflectivity and grayscale accuracy; in addition, the double fluid layer may have interlayer dislocation when bent, destroying the optical consistency. (2) The existing driving method is based on a planar state design and does not consider the local deformation difference caused by bending. Usually, the pixels in the bent area need to dynamically adjust the driving voltage to compensate for the deviation of the ink shrinkage rate to 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 microcracks when repeatedly bent, resulting in insulation layer breakage or insulation layer failure, which in turn causes leakage or electrochemical aging problems.

[0025] Based on at least one of the above reasons, the present invention proposes an electrowetting display panel, aiming to improve the flexibility of the electrowetting display panel and achieve a foldable display effect.

[0026] See also Figures 1 to 4 In one embodiment of the present invention, the electrowetting display panel 100 provided by the present invention includes a first substrate 1 and a second substrate 9 arranged opposite to each other, 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 distributed in an array, the pixel unit 61 having a first direction 100a and a second direction 100b perpendicular to each other, the pixel unit 61 including a plurality of sub-pixel units 611 spaced apart along the second direction 100b, each sub-pixel unit 611 extending along the first direction 100a; the electrode layer 2 is provided on the first substrate 1 toward the second substrate board 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 is enclosed with the first insulating layer 3 to form a plurality of accommodating cavities 5 spaced along the second direction 100b, each accommodating cavity 5 includes a connected storage bin 51 and a sub-pixel flow channel 52, the sub-pixel flow channel 52 is arranged corresponding to the sub-pixel unit 611, the storage bin 51 is filled with liquid, the liquid covers the corresponding sub-pixel flow channel 52 when the electrode layer 2 is not energized, and the liquid is stored in the corresponding storage bin 51 when the electrode layer 2 is energized.

[0027] 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 may be transparent glass, and the driving circuit layer may be a thin film transistor array layer. The specific structural arrangement may refer to the prior art and will not be described in detail here. A pixel wall 6 is provided on the first substrate 1, and the pixel wall 6 encloses a plurality of pixel units 61 distributed in an array. The pixel unit 61 may be a square structure, having a first direction 100a and a second direction 100b perpendicular to each other. The pixel unit 61 includes a plurality of sub-pixel units 611 distributed at intervals. The sub-pixel unit 611 is in the shape of an elongated strip, and its length direction extends along the first direction 100a, that is, the first direction 100a is the length direction of the sub-pixel unit 611, and the second direction 100b is the width direction of the sub-pixel unit 611. The plurality of sub-pixel units 611 are distributed at intervals along the second direction 100b. Optionally, the number of sub-pixel units 611 is three, namely, a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit. The electrode layer 2 is a transparent electrode layer, and its material composition 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, which is used to drive the morphological change of the electrowetting liquid. The first insulating layer 3 covers the electrode layer 2 and plays an insulating and protective role. At the same time, it serves as the contact interface of the liquid, and its surface characteristics 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 is enclosed with the first insulating layer 3 to form a plurality of accommodating cavities 5 spaced along the second direction 100b. The accommodating cavity 5 includes a connected storage bin 51 and a sub-pixel flow channel 52. The sub-pixel flow channel 52 is arranged corresponding to the sub-pixel unit 611. When the sub-pixel unit 611 is set to three, the sub-pixel flow channel 52 is also set to three accordingly, and the projection size of the sub-pixel flow channel 52 on the first substrate 1 is adapted to the projection size of the sub-pixel unit 611 on the first substrate 1. The storage bin 51 corresponds to the interval between the sub-pixel unit 611 and the pixel wall 6, and the storage bin 51 is filled with liquid. The liquid can be a dielectric ink 7 or a solution containing charged pigment particles, which is not limited here. The size of the storage bin 51 along the second direction 100b is larger than the size of the sub-pixel unit 611 along the second direction 100b. The specific size of the storage bin 51 should be determined according to the actual situation, so that the liquid can be completely stored in the storage bin 51. At the same time, it is also necessary to ensure that the liquid can completely cover the entire sub-pixel flow when it is expanded. When the electrode layer 2 is not energized, the liquid expands and covers the entire 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, and the sub-pixel is displayed normally. When the sub-pixel flow channel 52 is set to three, the three sub-pixel flow channels 52 are respectively covered with red ink 71, green ink 72 and blue ink 73, and color display can be achieved at this time.After the electrode layer 2 is energized, the liquid is controlled to move toward the storage chamber 51 under the action of the electric field of the electrode, thereby realizing pixel grayscale control; when the liquid is completely stored in the storage chamber 51, the sub-pixel displays the underlying color.

[0028] It should be noted that a reflective layer is deposited on the first substrate 1. When the liquid is completely stored in the storage chamber 51, the sub-pixel displays the color of the reflective layer. The reflective layer can be white, in which case the sub-pixel displays white.

[0029] After the electrode layer 2 is energized, the liquid is primarily guided by the electric field gradient distribution of the electrode layer 2 to direct the direction of force acting on the liquid, thereby causing the liquid to move toward the storage layer. In some embodiments, the thickness of the electrode layer 2 gradually decreases as it moves away from the storage compartment 51. At the same voltage, the electric field intensity is higher in areas with greater electrode thickness, causing the liquid to move toward areas with higher electric field intensity, i.e., toward the storage compartment 51. Of course, in other embodiments, the electrode layer 2 can also be configured in other structures, as long as it can drive the liquid to move toward the storage compartment 51.

[0030] In the technical solution provided by the present invention, a liquid single fluid is used and confined in the accommodating cavity 5. Under the capillary action of the sub-pixel flow channel 52, the liquid single fluid spreads over the entire sub-pixel flow channel 52 to enable the pixel to present the color of the liquid; and the existence state of the liquid single fluid is controlled by electrodes to achieve pixel grayscale display.

[0031] The present invention adopts a single liquid fluid design, which can effectively avoid the bending caused by flexibility, which may cause the liquid in the pixel area to be uncontrolled, thereby realizing pixel grayscale display. At the same time, it can also effectively avoid the optical consistency problem caused by the interlayer dislocation when the double fluid is bent. In addition, the sub-pixel flow channel 52 design is adopted, so that the movement trajectory of the liquid during bending is limited to the range of the sub-pixel flow channel 52. This constraint effect 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 mechanism during bending, which simplifies the design complexity of the driving system, is conducive to improving the flexibility of the electrowetting display panel 100, and realizes the effect of foldable display.

[0032] Please refer again Figure 1 and Figure 4 In an optional embodiment of the present invention, the electrode layer 2 includes a plurality of electrode portions 21, and 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 two electrode portions 21 located on opposite sides of the same sub-pixel unit 611 gradually increases in the direction away from the storage bin 51.

[0033] Specifically, the electrode portion 21 is arranged in a long strip shape and extends obliquely along the first direction 100a. Each sub-pixel unit 611 is provided with an electrode portion 21 on both opposite sides along the second direction 100b, that is, one sub-pixel unit 611 corresponds to a group of electrode portions 21, and the spacing between the two electrode portions 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. When the electrode portion 21 is energized, the electric field strength generated by it will increase as the spacing decreases. 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. Therefore, under the dielectric force, the fluid will move toward the direction close to the storage bin 51 and finally be stored in the storage bin 51.

[0034] The embodiment of the present invention uses a pair of electrode portions 21 with asymmetric spacing to drive the movement of liquid in the sub-pixel flow channel 52. This structure is relatively simple and easy to drive.

[0035] In some embodiments of the present invention, the electrode portion 21 is driven by an AC power supply, the voltage and frequency of which depend on the fluid characteristics and the desired grayscale. When the AC voltage is applied, a non-uniform electric field is generated between the two electrode portions 21 located on either side of the sub-pixel flow channel 52 because they are not parallel. When the dielectric fluid is subjected to the non-uniform electric field, it tends to accumulate in areas of high electric field intensity, thereby causing the liquid to move and achieving grayscale control.

[0036] In an optional embodiment of the present invention, the angle between the length direction of the electrode portion 21 and the first direction 100 a is defined as A, and 0°<A<30°.

[0037] The embodiment of the present invention limits the inclination angle of the electrode portion 21 to the above-mentioned range, so that the electric field lines can form a continuous and uniform gradient distribution along the direction from the end of the sub-pixel unit 611 to the storage bin 51, ensuring that the dielectric force acting on the liquid is always directed to the storage bin 51, thereby improving the stability of the liquid movement; at the same time, it can also effectively enhance the efficiency of the driving force and improve the response speed; improve the linearity of grayscale control and improve the accuracy of grayscale control; adapt to flexible bending scenes and ensure the consistency of grayscale display in flexible scenes.

[0038] Please refer again Figures 1 to 4 In an optional embodiment of the present invention, 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 to 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 to 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 hydrophilic insulating layer 41 enclose a sub-pixel flow channel 52, and the first hydrophilic insulating layer 32 and the second hydrophilic insulating layer 42 enclose a storage bin 51.

[0039] Specifically, the liquid is ink 7, which may be a colored ink. When there are three sub-pixel units 611, the colored ink 7 includes red ink 71, green ink 72, and blue ink 73, which are filled into the three sub-pixel channels 52 corresponding to the three sub-pixel units 611, 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 storage compartment 51, and the first hydrophilic insulating layer 32 is provided corresponding to the storage compartment 51. It should be noted that in order to ensure that the storage compartment 51 can accommodate a sufficient amount of ink 7 and that the ink 7 can completely cover the corresponding sub-pixel channel 52 when expanded, the size of the storage compartment 51 along the third direction 100c (i.e., the thickness direction) is larger than the size of the corresponding sub-pixel channel 52 along the third direction 100c (i.e., the thickness direction). In other words, the size of the first hydrophilic insulating layer 32 along the third direction 100c (i.e., the thickness direction) is smaller than the size of the first hydrophobic insulating layer 31 along the third direction 100c (i.e., the thickness direction). Among them, the first hydrophilic insulating layer 32 can be set through the side of the first hydrophobic insulating layer 31 facing the first substrate 1, of course, it can also be set not through the side of the first hydrophobic insulating layer 31 facing the first substrate 1, which is not limited here. The second insulating layer 4 also includes a second hydrophobic insulating layer and a second hydrophilic insulating layer 42. The second hydrophobic insulating layer 41 is set corresponding to the first hydrophobic insulating layer 31, and both are set corresponding to the area outside the storage bin 51. As a result, the two can enclose a plurality of spaced sub-pixel flow channels 52, and the ends of two adjacent sub-pixel flow channels 52 away from the storage bin 51 are not connected to each other. The second hydrophilic insulating layer 42 and the second hydrophilic insulating layer 42 are set correspondingly, and both are set corresponding to the storage bin 51. The two enclose a plurality of spaced storage bins 51.

[0040] When the electrode layer 2 is not energized, the colored ink located in the storage bin 51 will be spread over the corresponding sub-pixel 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 channel 52. At this time, the sub-pixel will present the color of the colored ink. When the sub-pixel channel 52 is set to three and is respectively covered with red ink 71, green ink 72 and blue ink 73, the entire pixel unit 61 realizes color display.

[0041] By rationally designing the surface properties (such as hydrophobicity) of the first insulating layer 3 and the second insulating layer 4, the embodiment of the present invention can ensure that the ink 7 can naturally and evenly cover the sub-pixel flow channel 52 by relying on surface tension and the capillary action of the sub-pixel flow channel 52 in the absence of an electric field.

[0042] Please refer again Figures 1 to 4In an optional embodiment of the present invention, the first insulating layer 3 further includes a third hydrophilic insulating layer 33, which is arranged at the end of the sub-pixel channel 52 away from the storage compartment 51 and extends along the second direction 100b; the second insulating layer 4 further includes a fourth hydrophilic insulating layer 43, which is arranged corresponding to the third hydrophilic insulating layer 33; two adjacent sub-pixel channels 52 are connected through the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43.

[0043] Specifically, the first insulating layer 3 includes 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 storage bin 51, and the third hydrophilic insulating layer 33 is arranged corresponding to the end of the sub-pixel channel away from the storage bin 51, and extends along the second direction 100b; accordingly, the specific structural setting of the second insulating layer 4 corresponds to the specific structural setting of the first insulating layer 3, thereby, the ends of two adjacent sub-pixel channels 52 away from the storage bin 51 are connected through the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43, which can facilitate better balancing of the air pressure and is beneficial to the flow of ink 7 in the sub-pixel channel 52. Furthermore, 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. 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, and this is not limited here. Since two adjacent storage chambers 51 are not connected to each other, that is, multiple first hydrophilic insulating layers 32 are arranged at intervals along the second direction 100b, the ink 7 in the storage chamber 51 flows in the direction away from the storage chamber 51 under the capillary action of the sub-pixel channel 52 and the surface tension of the first hydrophobic insulating layer 31. When it flows to the third hydrophilic insulating layer 33, the ink 7 stops moving due to the change in wetting gradient (that is, from a hydrophobic surface to a hydrophilic surface). In this way, the third hydrophilic insulating layer 33 and the fourth hydrophilic insulating layer 43 constitute an ink 7 stopping structure, and the ink 7 eventually covers the entire sub-pixel channel 52.

[0044] Optionally, the dimension (i.e., width) of the third hydrophilic insulating layer 33 along the first direction 100a is 5 μm-20 μm, for example, 5 μm, 10 μm, 15 μm, 20 μm, or any range between these two endpoints. This design can better balance the air pressure and facilitate the flow of the ink 7 within the sub-pixel flow channel 52.

[0045] Please refer again Figure 1 、 Figure 3 and Figure 4In an optional embodiment of the present invention, the electrowetting display panel 100 further includes a plurality of support columns 8, which are spaced apart along the first direction 100a at opposite sides of each sub-pixel unit 611 along the second direction 100b, and are all located between the first insulating layer 3 and the second insulating layer 4.

[0046] In the embodiment of the present invention, support pillars 8 are located between first insulating layer 3 and second insulating layer 4, and at intervals between sub-pixel flow channels 52, thereby supporting the sub-pixel flow channels 52. When pixel unit 61 is bent, the spacing of multiple support pillars 8 ensures that the sub-pixel flow channels 52 are spaced uniformly, thereby ensuring accurate grayscale control. Furthermore, support pillars 8 enhance the structural strength of the entire electrowetting display panel 100, reducing fatigue damage to the substrate and insulating layer caused by long-term folding and bending, thereby extending the service life of the display panel.

[0047] The cross-sectional outer contour of the support column 8 can be circular, polygonal or other reasonable shapes, 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 here.

[0048] Please refer again Figure 2 In an optional embodiment of the present invention, a plurality of through holes 34 are provided at intervals in the first insulating layer 3 and / or the second insulating layer 4 .

[0049] In the embodiment of the present invention, the hole-digging structure design of the first insulating layer 3 and / or the second insulating layer 4 can effectively avoid or reduce the probability of microcracks in the insulating layer during bending, thereby making the electrowetting display panel 100 conducive to achieving a foldable display effect.

[0050] 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 are designed with a hole structure. Preferably, the first insulating layer 3 and the second insulating layer 4 are both provided with a plurality of through holes 34 at intervals. The shape and size of the through holes 34 are not limited here.

[0051] It should be noted that the fundamental reason for microcracks in the insulating layer during bending is that the degree of deformation in the outward direction of the bend exceeds the maximum stretchability of the material. Reducing the material thickness can alleviate this problem to some extent, but this can easily lead to a decrease in the insulation layer's resistance, which in turn can cause leakage and affect pixel performance. However, the embodiments of the present invention, by creating holes in the first insulating layer 3 and / or the second insulating layer 4, effectively reduce the thickness of the insulating layer without compromising its insulation performance, thereby improving the bending resistance of the first insulating layer 3 and / or the second insulating layer 4.

[0052] Please refer again Figure 2In an optional embodiment of the present invention, a plurality of through holes 34 are provided at intervals on the two opposite surfaces of the first insulating layer 3 and the second insulating layer 4, and the plurality of through holes 34 on the two opposite surfaces are staggered.

[0053] In this embodiment of the present invention, both 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 perforated on opposing surfaces, and the multiple through-holes 34 located on the opposing surfaces are staggered. This design can more effectively avoid or reduce the probability of microcracks in the insulating layer during bending, thereby making the electrowetting display panel 100 more conducive to achieving a foldable display effect. Furthermore, this structural design can effectively reduce flow hysteresis and improve driving performance.

[0054] Please refer again Figure 1 and Figure 3 In an optional embodiment of the present invention, the electrowetting display panel 100 further includes a black matrix layer 10 , which is disposed between the second substrate 9 and the second insulating layer 4 and corresponding to the intervals of the sub-pixel units 611 .

[0055] In the embodiment of the present invention, the black matrix layer 10 is arranged at intervals corresponding to the sub-pixel units 611 to separate the sub-pixel units 611 to prevent light mixing and color bleeding. The black matrix layer 10 is formed of a black opaque layer, and its specific material composition is not limited here.

[0056] The present invention further provides an electrowetting display device, comprising an electrowetting display panel 100. The specific structure of the electrowetting display panel 100 is similar to that of the above-described embodiments. Since the present electrowetting display device utilizes all of the technical solutions of all of the above-described embodiments, it at least has all of the beneficial effects brought about by the technical solutions of the above-described embodiments, which will not be described in detail here. The electrowetting display device may be electrowetting electronic paper.

[0057] Because the electrowetting display panel 100 of the present invention adopts a single-liquid design, it can effectively avoid bending caused by flexibility, which can lead to uncontrolled force on the liquid in the pixel area, thus achieving pixel grayscale display. It can also effectively avoid optical consistency problems caused by interlayer misalignment when bending two fluids. In addition, the sub-pixel flow channel 52 design is adopted, so that the movement trajectory of the liquid during bending is limited within the scope of the sub-pixel flow channel 52. This constraint effect ensures that the position change of the liquid is only related to the electrode, that is, there is no need to consider compensation voltage or other compensation mechanisms during bending, which simplifies the design complexity of the drive system, helps to improve the flexibility of the electrowetting display panel 100, and achieve the effect of foldable display. In other words, the electrowetting electronic paper provided by the present invention is foldable electrowetting electronic paper.

[0058] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. An electrowetting display panel, characterized in that: include: A first substrate and a second substrate are disposed opposite to each other, the first substrate being provided with a plurality of pixel units distributed in an array, the pixel units having a first direction and a second direction perpendicular to each other, the pixel units including a plurality of sub-pixel units spaced apart along the second direction, each of the sub-pixel units extending along the first direction; an electrode layer, disposed on a surface of the first substrate facing the second substrate; a first insulating layer, disposed on a surface of the electrode layer facing the second substrate; as well as A second insulating layer is arranged on the surface of the second substrate facing the first substrate, and is enclosed with the first insulating layer to form a plurality of accommodating cavities spaced along the second direction, each of the accommodating cavities includes a connected storage bin and a sub-pixel flow channel, the sub-pixel flow channel is arranged corresponding to the sub-pixel unit, the storage bin is filled with liquid, the liquid covers the corresponding sub-pixel flow channel when the electrode layer is not energized, and the liquid is stored in the corresponding storage bin when the electrode layer is energized.

2. The electrowetting display panel according to claim 1, wherein: The electrode layer includes a plurality of electrode portions, the plurality of electrode portions are spaced apart and distributed along the second direction on two opposite sides of each sub-pixel unit, 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 a direction away from the storage compartment.

3. The electrowetting display panel according to claim 2, wherein: An angle between the length direction of the electrode portion and the first direction is defined as A, where 0°<A<30°.

4. The electrowetting display panel according to claim 1, wherein: The liquid is ink, the first insulating layer includes a first hydrophobic insulating layer and a first hydrophilic insulating layer connected to each other, and the first hydrophilic insulating layer is provided corresponding to the receiving compartment; The second insulating layer includes a second hydrophobic insulating layer and a second hydrophilic insulating layer connected to each other, and the second hydrophilic insulating layer is provided corresponding to the storage compartment; The first hydrophobic insulating layer and the second hydrophobic insulating layer together form the sub-pixel flow channel, and the first hydrophilic insulating layer and the second hydrophilic insulating layer together form the storage compartment.

5. The electrowetting display panel according to claim 4, wherein: The first insulating layer further includes a third hydrophilic insulating layer, the third hydrophilic insulating layer being provided corresponding to an end of the sub-pixel flow channel away from the receiving compartment and extending along the second direction; The second insulating layer further includes a fourth hydrophilic insulating layer, and the fourth hydrophilic insulating layer is arranged corresponding to the third hydrophilic insulating layer; Two adjacent sub-pixel flow channels are connected through the third hydrophilic insulating layer and the fourth hydrophilic insulating layer.

6. The electrowetting display panel according to any one of claims 1 to 5, characterized in that: The electrowetting display panel further includes a plurality of support columns, which are spaced apart along the first direction at two opposite sides of each sub-pixel unit along the second direction and are located between the first insulating layer and the second insulating layer.

7. The electrowetting display panel according to any one of claims 1 to 5, characterized in that: The first insulating layer and / or the second insulating layer are / is provided with a plurality of through holes at intervals.

8. The electrowetting display panel according to claim 7, wherein: A plurality of through holes are arranged at intervals on two opposite surfaces of the first insulating layer and the second insulating layer, and the plurality of through holes on the two opposite surfaces are staggered.

9. The electrowetting display panel according to any one of claims 1 to 5, characterized in that: The electrowetting display panel further includes a black matrix layer, which is disposed between the second substrate and the second insulating layer and is arranged corresponding to the intervals of the sub-pixel units.

10. An electrowetting display device, characterized in that: The invention comprises the electrowetting display panel according to any one of claims 1 to 9.

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