Electronic paper and method of making the same

Abstract

The application provides an electronic paper and a manufacturing method thereof. The electronic paper comprises: an array substrate and an upper substrate arranged oppositely; a pixel electrode arranged on one side of the array substrate facing the upper substrate; the manufacturing material of the pixel electrode comprises silver material, and the thickness of the pixel electrode is set to 1100-1500 mu m; a common electrode arranged on one side of the upper substrate facing the pixel electrode; and an electrophoretic particle layer filled between the pixel electrode and the common electrode. The electronic paper provided by the application can utilize the strong conductive performance of silver, and can improve the effective utilization rate of ambient light, so as to improve the display effect of the electronic paper. In addition, the pixel electrode with higher reflectivity can reduce the irradiation of ambient light on the channel of the thin film transistor in the array substrate, so as to prevent the thin film transistor from being electrically poor and affecting the display effect of the electronic paper. Therefore, the display effect of the electronic paper can be further improved and ensured.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of display, and particularly relates to an electronic paper and a manufacturing method thereof. BACKGROUND

[0002] Electronic paper is a new type of electronic display device. Current electronic paper products generally adopt cholesteric liquid crystal display technology, electrophoretic display technology (EPD) and electrowetting display technology. Among them, the electrophoretic display technology is the most promising technical approach, and the most commonly used medium for the electrophoretic display technology is electronic ink (E-ink). The electrophoresis (EP) phenomenon refers to the movement of charged particles under the action of an electric field, moving towards the electrode with opposite electric properties. The display panel prepared by using the electrophoresis phenomenon is an electrophoretic display panel. In the related art, the pixel electrode of the electronic paper is made of ITO material, which mainly utilizes the strong conductivity of the ITO material. However, the reflectivity of the ITO material to light is low, resulting in low utilization rate of ambient light of the electronic paper and reducing the display effect of the electronic paper. SUMMARY

[0003] Embodiments of the present application provide an electronic paper and a manufacturing method thereof to solve the problem of poor display effect of the existing electronic paper.

[0004] In a first aspect, embodiments of the present application provide an electronic paper, which comprises:

[0005] An array substrate and an upper substrate arranged oppositely;

[0006] A pixel electrode arranged on one side of the array substrate facing the upper substrate; the pixel electrode is made of silver material, and the thickness of the pixel electrode is set to 1100-1500 μm;

[0007] A common electrode arranged on one side of the upper substrate facing the pixel electrode;

[0008] An electrophoretic particle layer filled between the pixel electrode and the common electrode.

[0009] Optionally, the pixel electrode is provided with a hollow area.

[0010] Optionally, the electrophoretic particle layer comprises a micro-cup carrier, electrophoretic particles and electrophoretic liquid; the micro-cup carrier is formed with a micro-cup cavity, and the electrophoretic particles and the electrophoretic liquid are filled in the micro-cup cavity.

[0011] Optionally, the total area of the hollow area on the pixel electrode is less than or equal to half of the projection area of the micro-cup carrier on the array substrate.

[0012] Optionally, the height of the micro-cup cavity is set to 30-50 μm; and / or, the width of the micro-cup cavity is set to 40-100 μm.

[0013] Optionally, the micro-cup carrier has a cup mouth and a cup bottom, the micro-cup cavity is formed between the cup mouth and the cup bottom of the micro-cup carrier, and the cup mouth of the micro-cup carrier faces the common electrode; the electronic paper further comprises an encapsulation layer, which is arranged on the side of the common electrode facing the electrophoretic particle layer to cover the cup mouth of the micro-cup carrier.

[0014] Optionally, the thickness of the cup bottom of the micro-cup carrier is set to 1-2 μm.

[0015] Optionally, the electronic paper further comprises a color film layer, which is arranged between the upper substrate and the common electrode.

[0016] In a second aspect, the embodiments of the present application further provide a manufacturing method of electronic paper, which comprises the following steps:

[0017] providing a substrate substrate;

[0018] arranging a device layer on the substrate substrate;

[0019] arranging a pixel electrode on the device layer; wherein the material of the pixel electrode comprises silver material, and the thickness of the pixel electrode is set to 1100-1500 μm;

[0020] arranging a micro-cup carrier on the pixel electrode;

[0021] filling the micro-cup carrier with electrophoretic particles and electrophoretic liquid;

[0022] arranging an encapsulation layer on the micro-cup carrier;

[0023] arranging a common electrode on the encapsulation layer;

[0024] arranging an upper substrate on the common electrode.

[0025] Optionally, before the step of arranging the micro-cup carrier on the pixel electrode, the method further comprises:

[0026] arranging a hollowed-out area on the pixel electrode.

[0027] The electronic paper provided in this application uses silver as the pixel electrode, and the thickness of the pixel electrode is set to 1100μm to 1500μm. When the thickness of the silver material reaches 1100μm, its reflectivity increases. Therefore, using silver as the pixel electrode and setting its thickness to 1100μm to 1500μm utilizes silver's strong conductivity and improves the effective utilization of ambient light, thereby improving the display effect of the electronic paper. Furthermore, the higher reflectivity of the pixel electrode reduces the illumination of ambient light on the channels of the thin-film transistors in the array substrate, preventing electrical degradation of the thin-film transistors that could affect the display effect of the electronic paper. Thus, the display effect of the electronic paper can be further improved and guaranteed. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings. In the following description, the same reference numerals denote the same parts.

[0030] Figure 1 This is a cross-sectional schematic diagram of electronic paper provided in an embodiment of this application.

[0031] Figure 2 for Figure 1 The diagram shows a cross-sectional view of the array substrate in the electronic paper.

[0032] Figure 3 for Figure 1 The diagram shows a cross-sectional view of the electrophoretic particle layer in the electronic paper.

[0033] Figure 4 This is a schematic flowchart illustrating a method for manufacturing electronic paper according to an embodiment of this application. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0035] Embodiments of the present application provide an electronic paper and a manufacturing method thereof to solve the problem of poor display effect of the existing electronic paper. The embodiments will be described below with reference to the accompanying drawings.

[0036] The electronic paper provided by the embodiments of the present application can be applied to the preparation of an electronic display. For example, please refer to Figure 1 and Figure 2 , Figure 1 The cross-sectional schematic diagram of the electronic paper provided by an embodiment of the present application is shown. Figure 2 For Figure 1 The specific structure cross-sectional schematic diagram of the array substrate 10 in the electronic paper is shown.

[0037] The electronic paper includes an array substrate 10 and an upper substrate 20 arranged oppositely, a pixel electrode 30, a common electrode 40 and electrophoretic particles 5250. The pixel electrode 30 is arranged on one side of the array substrate 10 facing the upper substrate 20; the material of the pixel electrode 30 includes silver material, and the thickness d of the pixel electrode 30 is set to 1100 μm to 1500 μm; the common electrode 40 is arranged on one side of the upper substrate 20 facing the pixel electrode 30; and the electrophoretic particles 5250 are filled between the pixel electrode 30 and the common electrode 40.

[0038] The array substrate 10 includes a substrate 11 and a device layer 12 arranged on the substrate 11, and the device layer 12 includes a thin film transistor. For example, as shown in Figure 2 The thin film transistor includes, from bottom to top, a gate 121, a gate 121 insulating layer 122, an active layer 123, a source 124 and a drain 125 arranged in the same layer; and the pixel electrode 30 is electrically connected to the drain 125. After the thin film transistor charges the pixel electrode 30, an electric field is generated between the pixel electrode 30 and the common electrode 40, and the charged particles in the electrophoretic particles 5250 will exhibit electrophoresis under the action of the electric field. For example, the charged particles include black particles and white particles, and the charge polarities of the black particles and the white particles are opposite (respectively + and -). The black particles and the white particles move up and down between the array substrate 10 and the upper substrate 20 according to the electric field applied thereto. Therefore, by controlling the input voltage of the pixel electrode 30 through the thin film transistor, the charged particles of the electrophoretic particles 5250 can be moved correspondingly, thereby producing different combinations of white and black, and finally realizing the display of graphics and texts.

[0039] During the use of the electronic paper, ambient light can pass through the upper substrate 20 and irradiate the pixel electrode 30. The arrangement of the electrophoretic particles is displayed by the light reflected by the pixel electrode 30, i.e. the image. The higher the reflectivity of the pixel electrode 30, the better the display effect of the electronic paper. Silver has strong conductivity and can meet the voltage transmission requirement between the thin film transistor and the pixel electrode 30. When the thickness of the silver layer reaches 1100 μm, the reflectivity of the silver layer can be effectively improved and is higher than that of the ITO material. Therefore, the silver material can be used as the pixel electrode 30 to effectively improve the display effect of the electronic paper.

[0040] In addition, the increase of the reflectivity of the pixel electrode 30 can reduce the light transmitted through the pixel electrode 30 and irradiating the channel of the thin film transistor source-drain 125 to prevent the high light from increasing the potential energy of the electrons in the channel and causing the electrical property to deviate. Therefore, even if the electronic paper provided by the embodiment is used in a strong light environment, the display effect of the electronic paper can be effectively ensured. It should be noted that if the thickness d of the pixel electrode 30 is greater than 1500 μm, the overall thickness of the electronic paper will be thick and the production cost of the electronic paper will be increased. Therefore, the thickness d of the pixel electrode 30 is set to 1100 μm to 1500 μm, which can improve the display effect of the electronic paper and reasonably control the overall thickness and production cost of the electronic paper.

[0041] The electronic paper provided by the embodiment uses silver material as the pixel electrode 30 and sets the thickness d of the pixel electrode 30 to 1100 μm to 1500 μm. The reflectivity of the silver material to light can be improved when the thickness of the silver material reaches 1100 μm. Therefore, the pixel electrode 30 is made of silver material and the thickness d of the pixel electrode 30 is set to 1100 μm to 1500 μm, which can utilize the strong conductivity of silver and improve the effective utilization of ambient light to improve the display effect of the electronic paper. In addition, the pixel electrode 30 with higher reflectivity can reduce the irradiation of the channel of the thin film transistor in the array substrate 10 by ambient light to prevent the thin film transistor from deviating in electrical property and affecting the display effect of the electronic paper. Therefore, the display effect of the electronic paper can be further improved and ensured.

[0042] For example, Figure 1As shown, the electronic paper further comprises a color film layer 70 disposed between the upper substrate 20 and the common electrode 40. The color film layer 70 can be disposed in the region corresponding to the pixel electrode 30 on the upper substrate 20. After the light reflected by the pixel electrode 30 passes through the electrophoretic particles and then the color film layer 70, the colored light can be formed to achieve the colored image effect on the display surface of the electronic paper. For example, according to the imaging principle of three primary colors, a pixel can be formed by disposing a red color film layer 70 (R), a green color film layer 70 (G), and a blue color film layer 70 (B) in three sub-pixel regions to realize the color display of multiple colors.

[0043] For example, as shown in Figure 1 and Figure 3 , Figure 3 For example, as shown in Figure 1 the cross-sectional view of the electrophoretic particle 5250 in the electronic paper. The electrophoretic particle 5250 comprises a micro-cup carrier 51, electrophoretic particles, and electrophoretic liquid. The micro-cup carrier 51 forms a micro-cup cavity 511, and the electrophoretic particles and the electrophoretic liquid are filled in the micro-cup cavity 511. The micro-cup carrier 51 can be made of a photoresist material to hold the electrophoretic particles and the electrophoretic liquid to create a spatial environment for the electrophoretic particles to generate electrophoresis. The micro-cup carrier 51 can improve the structural stability of the electrophoretic particle 5250 to ensure the overall structural stability of the electronic paper.

[0044] For example, the pixel electrode 30 is provided with a hollow area. The hollow area can reduce the use of silver material without affecting the light reflection effect of the pixel electrode 30 to reduce the production cost of the electronic paper. Specifically, the total area of the hollow area on the pixel electrode 30 is less than or equal to half of the projection area of the micro-cup carrier 51 on the array substrate 10 to avoid affecting the reflectivity of the pixel electrode 30 to light due to the excessive hollow area.

[0045] For example, as shown in Figure 3 the height H of the micro-cup cavity 511 is set to 30 μm to 50 μm; and / or, the width L of the micro-cup cavity 511 is set to 40 μm to 100 μm. The height H of the micro-cup cavity 511 is the dimension of the micro-cup cavity 511 along the thickness direction of the pixel electrode 30. If the height H of the micro-cup cavity 511 is less than 30 μm, the capacity of the electrophoretic particles will be reduced, which affects the final display effect. If the height H of the micro-cup cavity 511 is greater than 50 μm, the overall thickness of the electronic paper will be thick. Therefore, the height H of the micro-cup cavity 511 is set to 30 μm to 50 μm. This can improve the display effect of the electronic paper and reasonably control the overall thickness and production cost of the electronic paper.

[0046] For example, as shown in Figure 1As shown, the micro-cup carrier 51 has a cup opening and a cup bottom, the micro-cup cavity 511 is formed between the cup opening and the cup bottom of the micro-cup carrier 51, and the cup opening of the micro-cup carrier 51 faces the common electrode 40; the electronic paper further comprises an encapsulation layer 60, which is arranged on the side of the common electrode 40 facing the electrophoretic particles 5250, and covers the cup opening of the micro-cup carrier 51. The encapsulation layer 60 can seal the micro-cup cavity 511 to prevent the electrophoretic liquid from leaking. The micro-cup cavity 511 corresponds to the plurality of sub-pixel regions of the pixel electrode 30, and a plurality of micro-cup cavities 511 are formed, which are covered by one encapsulation layer 60 to simplify the encapsulation process of the micro-cup cavity 511. Specifically, the thickness h of the cup bottom of the micro-cup carrier 51 is set to 1-2 μm to reasonably control the thickness of the micro-cup carrier 51 on the basis of ensuring the structural strength of the cup bottom.

[0047] Please refer to Figure 4 , Figure 4 A flowchart of a method for manufacturing electronic paper is provided in an embodiment of the present application. An embodiment of the present application further provides a method for manufacturing electronic paper to manufacture the electronic paper in the above embodiments, which comprises the following steps:

[0048] S10, providing a substrate 11;

[0049] S20, arranging a device layer 12 on the substrate 11;

[0050] S30, arranging a pixel electrode 30 on the device layer 12; wherein the material of the pixel electrode 30 comprises silver material, and the thickness of the pixel electrode 30 is set to 1100-1500 μm;

[0051] S40, arranging a micro-cup carrier 51 on the pixel electrode 30;

[0052] S50, filling electrophoretic particles and electrophoretic liquid into the micro-cup carrier 51;

[0053] S60, arranging an encapsulation layer 60 on the micro-cup carrier 51;

[0054] S70, arranging a common electrode 40 on the encapsulation layer 60;

[0055] S80, arranging an upper substrate 20 on the common electrode 40.

[0056] In step S10, the substrate 11 can be a glass substrate. In step S20, the device layer 12, i.e. the thin film transistor, comprises a gate 121, a gate 121 insulating layer 122, a source 124 and a drain 125 arranged in the same layer in sequence. Specifically, a layer of metal is deposited on the substrate 11 by PVD (Physical Vapor Deposition) technology and is patterned to form the gate 121. In the present embodiment, the metal material forming the gate 121 is molybdenum, and in other embodiments, other metal materials can also be used. Then, a layer of insulating material is deposited by PECVD (Plasma Enhanced Chemical Vapor Deposition) technology to form the gate 121 insulating layer 122. The gate 121 insulating layer 122 is arranged on the gate 121, i.e. the gate 121 is formed between the substrate 11 and the gate 121 insulating layer 122. In the present embodiment, the material of the gate 121 insulating layer 122 is silicon oxide, and in other embodiments, silicon nitride or other materials capable of achieving the purpose of insulation can also be used.

[0057] In step S30, a silver layer can be coated on the device layer 12 and is patterned to form the pixel electrode 30. Specifically, step S30 can further comprise step S31: arranging a hollow area on the pixel electrode 30. In this way, the material of the pixel electrode 30 can be saved to reduce the cost.

[0058] In step S40, the micro-cup carrier 51 can be made of a photoresist material. The photoresist is exposed by using photolithography technology to form the micro-cup cavity 511, and then the sealed electrophoretic particles 5250 are formed by steps S50 and S60. In step S70, the common electrode 40 can be made by evaporating ITO material on the encapsulation layer 60. After the common electrode 40 is made, the substrate 20 is covered to obtain the electronic paper of the above-described embodiments. Before the substrate 20 is covered, a color film layer 70, i.e. R / G / B color filter, can be printed on the common electrode 40 layer to realize the display of color graphics of the electronic paper.

[0059] In the above-described embodiments, the description of each embodiment focuses on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0060] In the description of the present application, the terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. The above describes the electronic paper provided by the embodiments of the present application in detail, and the principles and implementation modes of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed, and the above description of the present application should not be understood as a limitation.

Claims

1. An electronic paper, characterized in that, include: The array substrate and the upper substrate are positioned opposite each other; A pixel electrode is disposed on the side of the array substrate facing the upper substrate; the pixel electrode is made of silver and the thickness of the pixel electrode is set to 1100 μm to 1500 μm. A common electrode is disposed on the side of the upper substrate facing the pixel electrode; An electrophoretic particle layer is filled between the pixel electrode and the common electrode; The electrophoretic particle layer includes a microcup carrier, electrophoretic particles, and an electrophoretic solution; the microcup carrier forms a microcup cavity, and the electrophoretic particles and electrophoretic solution fill the microcup cavity. The height of the microcup cavity is set to 30μm to 50μm, and the width of the microcup cavity is set to 40μm to 100μm; The microcup carrier has a cup mouth and a cup bottom, and the microcup cavity is formed between the cup mouth and the cup bottom of the microcup carrier. The cup mouth of the microcup carrier faces the common electrode. The electronic paper also includes an encapsulation layer, which is disposed on the side of the common electrode facing the electrophoretic particle layer to cover the cup mouth of the microcup carrier. The thickness of the cup bottom of the microcup carrier is set to 1 μm to 2 μm.

2. The electronic paper according to claim 1, characterized in that, The pixel electrode has a hollowed-out area.

3. The electronic paper according to claim 1, characterized in that, The total area of ​​the hollowed-out areas on the pixel electrode is less than or equal to half of the projected area of ​​the microcup carrier on the array substrate.

4. The electronic paper according to any one of claims 1 to 3, characterized in that, The electronic paper also includes a color filter layer, which is disposed between the upper substrate and the common electrode.

5. A method for manufacturing electronic paper as described in any one of claims 1 to 4, characterized in that, include: Provide a substrate; A device layer is disposed on the substrate. A pixel electrode is disposed on the device layer; wherein the pixel electrode is made of silver and the thickness of the pixel electrode is set to 1100 μm to 1500 μm. A microcup carrier is disposed on the pixel electrode; Electrophoretic particles and electrophoretic solution are infused into the microcup carrier; An encapsulation layer is disposed on the microcup carrier; A common electrode is disposed on the encapsulation layer; An upper substrate is disposed on the common electrode.

6. The method for manufacturing electronic paper according to claim 5, characterized in that, Before the step of setting the microcup carrier on the pixel electrode, the method further includes: A hollow area is formed on the pixel electrode.

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