Electrophoretic electronic paper and method of manufacturing the same

Abstract

The embodiment of the present application provides an electrophoretic electronic paper, aiming at solving the problem of surface metal oxide and charge particle adsorption of at least one of the common electrode or the pixel electrode of the electrophoretic electronic paper. The electrophoretic electronic paper comprises an electrophoretic display cavity surrounded by a common electrode, a pixel electrode and an edge sealing structure, the display cavity comprises at least two kinds of pigment electrophoretic particles and a solution, the pigment electrophoretic particles are wrapped by the solution, a first isolation film arranged on the surface of the common electrode of the electrophoretic electronic paper is used for isolating the pigment electrophoretic particles from being adsorbed by the common electrode; the molecular material of the first isolation film comprises an electron-withdrawing group and an electron-donating group; a second isolation film arranged on the surface of the pixel electrode of the electrophoretic electronic paper is used for isolating the pigment electrophoretic particles from being adsorbed by the pixel electrode; and the water contact angle of the second isolation film is greater than 90o. Therefore, the service life of the electronic paper is prolonged.

Description

TECHNICAL FIELD

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

[0002] The electrophoretic electronic paper is a high-tech display technology, which displays images and texts by placing a large number of micro-charge particles in a micro space and making them move under the control of a medium field. These micro-charge particles are usually colloidal particles with a diameter of tens or hundreds of nanometers, sub-microns, or 1-5 microns. These particles are generally referred to as pigment electrophoretic particles, which are wrapped in a solution and stored in a cavity. The upper and lower electrodes of the cavity exert an electric field on the pigment electrophoretic particles, which will move in a direction perpendicular to the electric field, thereby changing their color.

[0003] The upper electrode is generally referred to as a common electrode, and the lower electrode is referred to as a pixel electrode. Due to the material of the electrodes, there is a probability that the pigment electrophoretic particles will be adsorbed on the electrodes, and even if the electric field is changed, the adsorption effect cannot be eliminated, which leads to irreversible display effects and seriously affects the service life of the electronic paper.

[0004] Therefore, it is urgent to provide a new structure of electrophoretic electronic paper to solve the above technical problems. SUMMARY

[0005] To solve the defects of the prior art, the present application aims to solve the problem of adsorption of the pixel electrode and the common electrode of the electrophoretic electronic paper and the charge particles.

[0006] The first aspect of the present application provides an electrophoretic electronic paper, comprising:

[0007] An electrophoretic display cavity surrounded by a common electrode, a pixel electrode and a sealing edge structure, the display cavity comprising at least two kinds of pigment electrophoretic particles and a solution, the pigment electrophoretic particles being wrapped by the solution,

[0008] A first isolation film arranged on the surface of the common electrode of the electrophoretic electronic paper, for isolating the pigment electrophoretic particles from being adsorbed by the common electrode; the molecular material of the first isolation film comprises an electron-withdrawing group and an electron-donating group;

[0009] A second isolation film arranged on the surface of the pixel electrode of the electrophoretic electronic paper, for isolating the pigment electrophoretic particles from being adsorbed by the pixel electrode; the water contact angle of the second isolation film is greater than 90°.

[0010] Optionally, the ratio between the electron-donating group and the electron-withdrawing group in the molecular material of the first isolation film is 1:5-5:1.

[0011] Optionally, the ratio between the electron-donating group and the electron-withdrawing group in the molecular material in the first separation film is 1:2-2:1.

[0012] Optionally, the volume resistivity of the first separation film is less than or equal to 10 15 Ω·cm.

[0013] Optionally, the transmittance of the first separation film is greater than or equal to 80%.

[0014] Optionally, the second separation film comprises one or more combinations of low surface tension materials, small molecule materials, or fluorine-containing organic compounds and derivatives thereof.

[0015] Optionally, the second separation film material comprises one or more combinations of PMMA, transparent PP, PE, transparent PA, SAN, AS, MS, MBS, PES, cellulose acetate, cellulose nitrate, EVA, fluorocarbon compounds and high molecular materials prepared from fluorocarbon compounds, polyaniline, polyurethane polymer, acrylic polymer, and natural polymer.

[0016] Optionally, the electrophoretic display cavity is separated by a plurality of transparent separators, and the electrophoretic display cavities separated by the transparent separators are connected or not connected.

[0017] Optionally, the cross section of the transparent separator is a regular shape, such as a square, a pentagon, a hexagon, a circle, a triangle, a trapezoid, an ellipse, or other shapes, or an irregular shape.

[0018] The second aspect of the present application provides a method for manufacturing an electrophoretic electronic paper, which uses the first separation film and the second separation film as described above.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] Compared with the prior art, the present application has the following beneficial effects: BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 Structure diagram of one embodiment of electrophoretic electronic paper of the present application. DETAILED DESCRIPTION

[0022] Please refer to Figure 1 , the first embodiment of the electrophoretic electronic paper of the present application, the structure includes:

[0023] Transparent cover plate 1, common electrode 2, first isolation film 3, electrophoretic display cavity 4, pixel electrode 5 and second isolation film 6.

[0024] The electrophoretic display cavity 4 further includes transparent barrier 43, pigment electrophoretic particles 41 and electrophoretic liquid 42, a plurality of transparent barriers 43 separate the electrophoretic display cavity 4 into a plurality of display units, and the display units are in communication with each other. Each display unit is filled with electrophoretic liquid 42, and the pigment electrophoretic particles 41 are immersed in the electrophoretic liquid 42.

[0025] The first isolation film 3 is arranged on the surface of the common electrode 2 of the electrophoretic electronic paper, which is used to isolate the pigment electrophoretic particles from being adsorbed by the common electrode, and the molecular structure of the first isolation film material contains both electron-withdrawing groups and electron-donating groups; The second isolation film is arranged on the surface of the pixel electrode, which is used to isolate the pigment electrophoretic particles from being adsorbed by the surface of the pixel electrode, and the water contact angle of the second isolation film is greater than 90°, preferably greater than 100°.

[0026] It should be noted that the transmittance of the first isolation film 3 is greater than or equal to 80%. Since the second isolation film 6 is located below the electrophoretic display cavity 4, it will not affect the display effect, and it can be transparent or opaque. In actual application, a specific material can be used to form an isolation film on the surface of the pixel electrode and the surface of the transparent barrier by evaporation. The isolation film material arranged on the surface of the pixel electrode includes fluorine-containing polymers, such as perfluorinated polymers, such as TEFLON-PTFE (polytetrafluoroethylene), TEFLON-AF (amorphous polytetrafluoroethylene copolymer), CYTOP (poly (perfluoro-butyl vinyl ether)) or FLUOROPEL (perfluoroalkyl copolymer).

[0027] It should be noted that the first isolation film is arranged on the surface of the common electrode of the electrophoretic electronic paper, which is used to isolate the pigment electrophoretic particles from being adsorbed by the common electrode, and the molecular structure of the isolation film material contains both electron-withdrawing groups and electron-donating groups. It can be understood that the molecular structure of the isolation film material includes both electron-withdrawing groups and electron-donating groups.

[0028] In this embodiment, the ratio between the electron-donating groups and the electron-withdrawing groups is between 1:5 and 5:1, preferably between 1:2 and 2:1. Controlling the ratio of the electron-donating groups and the electron-withdrawing groups of the first separation film allows the use of different types of compounds and functional groups. For example, functional groups such as nitro, carbonyl, methyl, etc. can be used to adjust the charge properties of the surface of the separation film. The following are several compounds and functional groups that can be used:

[0029] (1) p-fluoroaniline: contains p-fluoro phenyl and amine functional groups, which can make the surface electron-withdrawing;

[0030] (2) aniline: contains phenyl and amine functional groups, which can make the surface electron-donating;

[0031] (3) organic amines: including seven categories of aliphatic amines, alcohol amines, amides, alicyclic amines, aromatic amines, naphthalene amines, and other amines.

[0032] (4) acrylic acid: contains carboxyl functional groups, which can form negative charges on the surface, making the surface electron-withdrawing;

[0033] (5) methacrylic acid: contains carboxyl and methyl functional groups, which can form positively charged acidic functional groups on the surface, making the surface electron-donating.

[0034] Electron-donating groups and electron-withdrawing groups are concepts in organic chemistry that describe the relative electron affinity between different functional groups in some organic molecules. Generally, when both electron-donating groups and electron-withdrawing groups exist in an organic molecule, the relative ratio between them will affect the properties of the molecule. Some common electron-donating groups include -NH2, -NHR, -NR1R2, -N + R1R2R3, or other functional groups containing amine, imine, amide, etc. which can donate electrons to the center of the molecule, making the molecule positively charged. Some common electron-withdrawing groups include -C=O, -NO2, -CN, -F, -Cl, -Br, -I, -COOH, -SO3H, -SH, -C≡CH, -OCH3, -OH, -C6H5, -CH=CH2, etc. which can attract electrons from the center of the molecule, making the molecule negatively charged.

[0035] Preferably, the volume resistivity of the first separation film is less than or equal to 10 15 Ω·cm.

[0036] Preferably, the thickness of the first separation film is between 0.001 and 25 microns.

[0037] The second separation film can be achieved by using some hydrophobic materials or surface modification, including but not limited to the following materials: fluorides such as tin fluoride, indium fluoride, etc., hydrophobic surface modifiers such as hexafluoroacrylic acid, cetyltrimethylammonium bromide, etc.; these materials can form a homogeneous thin film on the surface of the transparent common electrode, or form a composite layer with low surface tension on the surface of other films. In addition, one of the methods that can be selected is to form a hydrophobic nanostructure on the surface of the second separation film: such as hydrophobic nanorods, hydrophobic nanospheres, etc. A nanostructure can be formed on the surface of the second separation film, thereby increasing the hydrophobicity of the surface.

[0038] The second separation film material in this embodiment includes one or a combination of low surface tension materials, small molecule materials, or fluorine-containing organic compounds and their derivatives, and preferably includes one or a combination of PMMA, transparent PP, PE, transparent PA, SAN, AS, MS, MBS, PES, cellulose acetate, cellulose nitrate, EVA, fluorocarbon compounds, polyaniline, polyurethane polymer, acrylic polymer, and natural polymer.

[0039] Preferably, the thickness of the second separation film is 0.001-5 microns, preferably 0.001-0.1 microns or 0.001-0.05 microns.

[0040] It should be noted that the method for preparing the first separation film and the second separation film described above includes the following steps, but is not limited to the following steps:

[0041] 1. Prepare specific materials including but not limited to PMMA, transparent PP, PE, transparent PA, SAN, AS, MS, MBS, PES, cellulose acetate, cellulose nitrate, EVA, fluorocarbon compounds, and polymer materials prepared from fluorocarbon compounds, polyaniline, polyurethane polymer, acrylic polymer, and natural polymer.

[0042] 2. Prepare a thin film using a solution method or a gas phase deposition method for the selected material. The solution method is to add the selected material to an appropriate amount of solvent and stir thoroughly until the material is completely dissolved. The gas phase deposition method includes physical vapor deposition (PVD) and chemical vapor deposition (CVD).

[0043] It should be noted that the physical vapor deposition technology in the present application refers to a technology of depositing a thin film with a certain special function on a substrate surface by a low-pressure gas (or plasma) process under vacuum conditions by using a physical method to vaporize a material source (solid or liquid) on the surface into gaseous atoms or molecules, or partially ionize into ions. Physical vapor deposition is one of the main surface treatment technologies. PVD coating technology is mainly divided into three categories: vacuum evaporation coating, vacuum sputtering coating and vacuum ion coating. The main methods of physical vapor deposition include vacuum evaporation, sputtering coating, arc plasma coating, ion coating and molecular beam epitaxy. The corresponding vacuum coating equipment includes vacuum evaporation coating machine, vacuum sputtering coating machine and vacuum ion coating machine. Physical vapor deposition technology can deposit metal film, alloy film, compound, ceramic, semiconductor, polymer film, etc. Chemical vapor deposition is a chemical technology, which is a method of generating a thin film on a substrate surface by chemical reaction of one or more gas phase compounds or elements containing thin film elements. The material of chemical vapor deposition can be oxide, sulfide, nitride, carbide, also can be binary or multi-element compound among III-V, II-IV, IV-VI groups, and their physical function can be accurately controlled by gas phase doping deposition process.

[0044] The second embodiment of the electrophoretic electronic paper of the present application is different from the foregoing embodiments in that the electrophoretic display units separated by the transparent partition are not communicated with each other. The other structures are the same and will not be described herein.

[0045] It should be noted that the cross section of the transparent partition can be regular shape, such as square, circle, triangle, trapezoid, pentagon, hexagon, ellipse or other shape, and irregular shape in actual manufacturing. It should be noted that the transparent partition separates the electrophoretic display cavity into display units communicated with each other or not communicated with each other, and the structure of each sub unit includes but is not limited to micro-cup or micro-pool structure.

[0046] The second aspect of the present application provides an electronic paper manufacturing method, comprising:

[0047] I. Preparation of pigment electrophoretic particles:

[0048] The pigment electrophoretic particles in the present application are positively charged or negatively charged or electrically neutral. The pigments include titanium white, zinc white, zinc oxide, silica, iron black, carbon black, chromite, chromate, silicate, chromium oxide green, lead chrome green, copper, titanium yellow, chromium yellow, iron yellow, lead chrome green, manganese violet, iron blue, cobalt blue, zinc white, cadmium yellow, cadmium red, barium sulfate, molybdenum orange, ultramarine, azure blue, jade green, emerald green, etc. The pigments of the charged pigment particles can be micronized, and the particle size is preferably 0.01-5 microns. The pigments of the neutral pigment particles can also be micronized, and the particle size is preferably 0.1-1 micron. The micronization methods include grinding and crushing, ultrasonic, solvent dispersion, etc., and the related equipment can include a colloidal mill, a ball mill, a frozen crusher, an ultrasonic machine, etc. In addition, the pigments of the neutral pigment particles and the charged pigment particles can be surface treated by physical or chemical methods to increase their stability in the solvent. The physical methods mainly include physical adsorption of polymers and surfactants on the surface of the pigment particles, and the chemical methods mainly include silane modification, polymer grafting or linking other small molecule compounds or surfactant compounds on the surface of the pigment particles by chemical bonds, etc. The low polarity dispersion solvent can be aromatic hydrocarbons such as toluene, benzene, xylene, etc., and halogenated hydrocarbons such as chloroform, tetrachloroethylene, etc. Generally, the number of carbon atoms in the aromatic hydrocarbons and halogenated hydrocarbons is less than 30. The non-polar dispersion solvent can be straight-chain, branched-chain and cyclic aliphatic hydrocarbons such as n-hexane, nonane, kerosene, synthetic isoparaffin, synthetic paraffin, synthetic naphthene, synthetic alkane, cyclohexane, etc., and halogenated hydrocarbons such as carbon tetrachloride, etc. Generally, the number of carbon atoms in the aliphatic hydrocarbons and halogenated hydrocarbons is less than 30. The electrophoretic display fluid containing electrically neutral pigment particles also has good display performance, which is manifested as follows: the neutral pigment particles are used as a high-efficiency dyeing agent to produce a background color of the electrophoretic fluid, but do not participate in the electrophoretic behavior of the particles under the action of an electric field. Under the action of an electric field, only the charged pigment particles move, and the charged pigment particles move up and down in the microcapsule, combined with the background color produced by the neutral pigment particles, to make the observer produce visual color change, achieving the purpose of display.

[0049] The pigment electrophoretic particles are surrounded by an electrophoretic display solution, which includes: 5-30 parts by weight of negatively or positively charged pigment particles, or 5-30 parts by weight of neutral pigment particles of a different color from the charged pigment particles; and 20-70 parts by weight of a low-polarity and / or non-polar dispersing solvent. It may also include 0.1-10 parts by weight of a thickening stabilizer. The preferred composition of the electrophoretic display solution containing neutral electrophoretic display particles is: 40-60 parts by weight of the dispersing solvent; 10-20 parts by weight of the charged pigment particles; 10-20 parts by weight of the neutral pigment particles; and 0.5-5 parts by weight of the thickening stabilizer. The listed composition ranges are merely examples for ease of explanation of the composition of the electrophoretic display solution. These figures do not imply that the composition of each component is limited to the listed ranges; in actual electrophoretic display solutions, the composition of each component can be within a wider range. Furthermore, the components of the electrophoretic display solution are not limited to those listed above, but may also include other components required for the preparation of the electrophoretic display solution and display device, such as, but not limited to, charge control agents like OLOA11000, surface tension control agents like Span80, wetting and dispersing agents like polyether-modified trisiloxanes and other organosilicon surfactants, as well as combinations thereof. The various components listed in other parts of this patent, or others, are equally applicable to the situation described herein.

[0050] This electrophoretic display solution containing neutral electrophoretic particles can achieve the display purpose by controlling the electrophoretic behavior of only one type of particle, fundamentally avoiding the problem of mutual adsorption and aggregation of positive and negative electrophoretic particles. This improves the performance and reproducibility of electrophoretic display and greatly simplifies the reaction process and preparation. Compared with electrophoretic materials produced by other methods, since the electrophoretic solution is composed of charged pigment particles and neutral pigment particles, there is no attraction process between charged pigment particles due to the presence of positive and negative charges. This fundamentally avoids particle aggregation caused by different charges. Because there is no electrostatic attraction between particles, the chemical treatment process for charged and neutral pigment particles becomes simpler, eliminating the need for multiple synthesis steps and effectively simplifying the reaction process. At the same time, due to the simplified interparticle interaction forces within the electrophoretic display solution, the preparation process is also simplified accordingly. No additional components need to be added, avoiding cumbersome preparation processes. This greatly improves the preparation efficiency and production reproducibility of the electrophoretic display solution, and significantly saves material costs.

[0051] The thickening stabilizer is selected from polymethyl methacrylate, polyethylene, polypropylene, polystyrene, rubbers such as polyisoprene, polyisobutylene or mixtures thereof, preferably polyisoprene, polyisobutylene and / or other reagents.

[0052] II. Preparation of electrophoresis buffer, specifically including:

[0053] 1) Preparation of neutral pigment particles; the weight parts of each reactant in the synthesis of the neutral pigment particles are: dispersing solvent 30-60, high molecular monomer 20-35, pigment 20-35, coupling agent 0.1-5, high molecular reaction chain initiator 0.001-5; preferably, dispersing solvent 40-50; high molecular monomer 25-30; pigment 25-30; coupling agent 0.5-3; high molecular reaction chain initiator 0.1-3. The synthesis method of the neutral pigment particles is characterized in that the electric neutrality of the pigment particles is controlled by surface treatment of the pigment particles and by surface grafting of neutral high molecules; the particles synthesized by this method have good dispersibility, high suspension stability, high color hiding power, no charge, no aggregation, and no charge attraction with charged pigment particles to cause particle aggregation. This synthesis method is applicable to various inorganic oxides, inorganic salts, and composite inorganic salt pigments. The high molecular monomer is a small molecule with low polarity or non-polarity that can undergo high molecular polymerization, including but not limited to methyl methacrylate, olefins or diolefins such as styrene, butadiene, halogenated olefins such as vinyl chloride, and mixtures and derivatives thereof; preferably, acrylate, methyl methacrylate such as lauryl methacrylate, styrene, and mixtures and derivatives thereof. The pigments include but are not limited to titanium white, zinc white, zinc oxide, silica, iron black, carbon black, chromite, chromate, silicate, chromium oxide green, lead chromium green, copper oxide, titanium yellow, chromium yellow, iron yellow, lead chromium green, manganese violet, iron blue, cobalt blue, zinc white, cadmium yellow, cadmium red, barium sulfate, molybdenum orange, ultramarine, azure blue, jade green, emerald green, and the like, with a particle size of less than 10 microns, preferably 0.01-5 microns, and most preferably 0.1-1 microns. The coupling agent needs to have an unsaturated functional group and be capable of high molecular reaction; it includes but is not limited to titanium ester coupling agents and aluminum ester coupling agents, etc.; the preferred coupling agent is a titanium ester coupling agent, and the unsaturated functional groups include double bonds, triple bonds, conjugated double bonds, and the like. The high molecular reaction chain initiator is selected from but not limited to: azo chain initiators such as azobisisobutyronitrile (AIBN) and azobisisoheptyl nitrile, and organic peroxide initiators such as dibenzoyl peroxide (BPO), dodecanoyl peroxide, dicumyl peroxide, ditert-butyl peroxide, tert-butyl benzoate peroxide, tert-amyl peroxide, diisopropyl peroxydicarbonate, dicyclohexyl peroxydicarbonate, cumyl hydroperoxide, tert-butyl hydroperoxide, and various oil-soluble oxidation-reduction chain initiators, and the like; the most preferred are azobisisobutyronitrile, azobisisoheptyl nitrile, dibenzoyl peroxide (BPO), and dicumyl peroxide.

[0054] The synthesis reaction of the neutral pigment particles of the present application can be carried out at a temperature range of 35-120 degrees Celsius, and the optimal reaction temperature is 70-85 degrees Celsius. The reaction time can be 4-48 hours, and the optimal reaction time is 12-16 hours. The reaction can be carried out in an air environment or under inert gas protection, and the optimal reaction environment is under nitrogen or helium protection. The collection of the product can be carried out by centrifugal separation after the reaction is completed, and the centrifugal separation is generally carried out at 2000-5000 RPM, preferably 3500-4000 RPM, and then the collected precipitate is preferably washed several times with an organic solvent such as toluene to obtain the neutral pigment particle product. Among them, the synthesis of the charged pigment particles includes: mixing 20-35 pigment particles, 20-35 polymer monomers, 0.1-5 coupling agents and 0.001-5 polymer reaction chain initiators in 30-60 dispersion solvents in weight parts at a temperature range of 30-120 degrees Celsius, and reacting for 12-16 hours under nitrogen protection. The coupling agent for preparing the charged pigment particles is generally selected to be silane, which tends to form charged particles.

[0055] 2) Preparation of charged pigment particles; the process for preparing charged particles is basically similar to the process for preparing neutral particles described above, wherein the coupling agent for preparing positively or negatively charged particles is selected to be silane, but the functional groups are different, and the electron-withdrawing group is negatively charged, and the electron-donating group is positively charged, so that the charging behavior of the particles can be controlled. For example: the coupling agent with propenoic acid functional group and other electron-withdrawing functional groups makes the particles negatively charged, and the coupling agent with amine group and other electron-donating functional groups makes the particles positively charged.

[0056] 3) Preparation of electrophoretic display liquid: mix 5-30 weight parts of charged pigment particles with 20-70 weight parts of dispersion solvent, and perform ultrasonic dispersion, and the ultrasonic dispersion time is generally 10-60 minutes, preferably 20-30 minutes, to prepare a dispersion liquid; then put 5-30 weight parts of neutral pigment particles into the dispersion liquid under ultrasonic state, and continue to perform ultrasonic dispersion, and the ultrasonic dispersion time is generally 10-60 minutes, preferably 20-30 minutes, to prepare an electrophoretic display liquid. If the dispersion liquid is mixed uniformly, the prepared electrophoretic display liquid has better effect.

[0057] Preferably, the step of preparing the electrophoretic display liquid further comprises the step of adding 0.1-10 parts by weight of thickening stabilizer into the electrophoretic display liquid. The step of adding the thickening stabilizer comprises the following steps: mixing 5-30 parts by weight of charged pigment particles and 18-60 parts by weight of dispersion solvent, and performing ultrasonic dispersion to obtain a dispersion liquid. Then, 5-30 parts by weight of neutral pigment particles are added into the dispersion liquid under ultrasonic state, and the ultrasonic dispersion is continued. A solution is prepared by dissolving 0.1-10 parts by weight of thickening stabilizer in 2-10 parts by weight of dispersion solvent, and then the solution is added into the above dispersion liquid to obtain the electrophoretic display liquid. Preferably, the electrophoretic display liquid comprises 40-60 parts by weight of the total amount of the dispersion solvent, 10-20 parts by weight of the charged pigment particles, 10-20 parts by weight of the neutral pigment particles, and 0.5-5 parts by weight of the thickening stabilizer. The synthesis method of the neutral pigment particles comprises the following steps: mixing the pigment particles, high molecular monomer, coupling agent and high molecular reaction chain initiator together in the dispersion solvent, and reacting at a temperature of 30-120°C for 4-48 hours.

[0058] The dispersion solvent for preparing the neutral pigment particles and the charged pigment particles comprises various non-polar and / or low-polar organic solvents and mixtures thereof. The low-polar dispersion solvent includes, but is not limited to, various aromatic hydrocarbons such as toluene, benzene, xylene, and halogenated hydrocarbons such as, but not limited to, chloroform, tetrachloroethylene, etc. The non-polar dispersion solvent includes, but is not limited to, various straight-chain, branched-chain and cyclic aliphatic hydrocarbons such as, but not limited to, n-hexane, nonane, decane, synthetic isoparaffin (Isopar), synthetic paraffin (Norpar), synthetic cycloparaffin (Nappar), synthetic alkane (Varsol / Naphtha), cyclohexane, and halogenated hydrocarbons such as, but not limited to, carbon tetrachloride, etc.

[0059] The thickening stabilizer for preparing the electrophoretic display liquid can be a non-polar polymer, including, but not limited to, polymethyl methacrylate, polyethylene, polypropylene, rubber such as polyisoprene, polyisobutylene, etc., among which polymethyl methacrylate, polyisoprene and polyisobutylene are the best choices.

[0060] In addition, other ingredients required for preparing the electrophoretic display liquid and display device can be added when preparing the electrophoretic display liquid, such as, but not limited to, charge control agent, surface tension control agent, dispersion wetting agent and combinations thereof.

[0061] III. The electrophoretic display cavity is prepared by combining the electrophoretic liquid prepared in the second step and the first spacer film and the second spacer film. The structures of the first spacer film and the second spacer film have been described above, and will not be repeated here.

[0062] In the embodiment, the electrophoretic electronic paper manufactured by the manufacturing method comprises a first isolation film arranged on the common electrode surface of the electrophoretic electronic paper for isolating the pigment electrophoretic particles from being adsorbed by the common electrode, and the molecular material of the first isolation film comprises an electron-withdrawing group and an electron-donating group; and the electrophoretic electronic paper further comprises a second isolation film arranged on the pixel electrode surface of the electrophoretic electronic paper for isolating the pigment electrophoretic particles from being adsorbed by the pixel electrode, and the water contact angle of the second isolation film is greater than 90°. Thus, the first isolation film has the effect of isolating the pigment electrophoretic particles from being adsorbed by the common electrode, and the second isolation film has the effect of isolating the pigment electrophoretic particles from being adsorbed by the pixel electrode surface. The problem of adsorption between the pixel electrode and the common electrode of the electrophoretic electronic paper and the charge particles is effectively solved. In addition, the manufacturing method adopted by the application is relatively simple, can be compatible with the existing manufacturing process, and has high feasibility and economy.

[0063] Although the preferred embodiments of the application have been described, those skilled in the art will be able to make additional changes and modifications to these embodiments once they have the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the application.

[0064] Obviously, those skilled in the art can make various modifications and variations to the application without departing from the spirit and scope of the application. Thus, if these modifications and variations of the application fall within the scope of the claims of the application and their equivalent technologies, the application also intends to include these modifications and variations.

Claims

1. An electrophoretic electronic paper, characterized by, The application relates to an electrophoretic display cavity formed by a common electrode, a pixel electrode and a sealing structure, at least two kinds of pigment electrophoretic particles and a solution in the electrophoretic display cavity, the pigment electrophoretic particles being wrapped by the solution, a first isolation film arranged on the surface of the common electrode of the electrophoretic electronic paper and used for isolating the pigment electrophoretic particles from being adsorbed by the common electrode; the molecular material of the first isolation film comprises an electron-accepting group and an electron-donating group. A second isolation film arranged on the surface of the pixel electrode of the electrophoretic electronic paper and used for isolating the pigment electrophoretic particles from being adsorbed by the pixel electrode; the water contact angle of the second isolation film is greater than 90 DEG. The ratio between the electron-accepting group and the electron-donating group in the molecular material in the first isolation film is controlled to be 1:5-5:

1.

2. The electrophoretic electronic paper according to claim 1, wherein: The ratio between the electron-accepting group and the electron-donating group in the molecular material in the first isolation film is controlled to be 1:2-2:

1.

3. The electrophoretic electronic paper according to claim 1, wherein: The volume resistivity of the first isolation film is less than or equal to 1015 ohm*cm.

4. The electrophoretic electronic paper according to claim 1, wherein: The transmittance of the first isolation film is greater than or equal to 80%.

5. The electrophoretic electronic paper according to claim 1, wherein: The second isolation film comprises one or more combinations of low surface tension material, small molecule material or fluorine-containing organic compound and derivatives thereof.

6. The electrophoretic electronic paper according to claim 1, wherein: The second isolation film material comprises one or more combinations of PMMA, transparent PP, PE, transparent PA, SAN, AS, MS, MBS, PES, cellulose acetate, cellulose nitrate, EVA, fluorocarbon compound and polymer material prepared from the fluorocarbon compound, polyaniline, polyurethane polymer, acrylic polymer and natural polymer.

7. The electrophoretic electronic paper according to claim 1, wherein: The electrophoretic display cavity is divided by a plurality of transparent isolation pieces, and the electrophoretic display cavities divided by the transparent isolation pieces are communicated or not communicated.

8. The electrophoretic electronic paper according to any one of claims 1 to 7, wherein: The cross section of the transparent isolation piece is a regular shape, for example, a square, a pentagon, a hexagon, a circle, a triangle, a trapezoid, an ellipse or other regular shapes.

9. The electrophoretic electronic paper according to claim 8, characterized by: The first isolation film and the second isolation film are applied.

10. A method of manufacturing electrophoretic electronic paper, characterized by: ​

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