A color electronic paper with mesh filter film

Abstract

A color electronic paper with a mesh filter film includes a first cholesteric liquid crystal structure unit, a second cholesteric liquid crystal structure unit, a mesh filter film, and a black-and-white switching layer unit. The first and second cholesteric liquid crystal structure units are stacked or arranged side-by-side. The black-and-white switching layer unit is located below the first or second cholesteric liquid crystal structure unit, and the mesh filter film is located between the first or second cholesteric liquid crystal structure unit and the black-and-white switching layer unit. This design overcomes the low reflectivity of cholesteric liquid crystals in the long-wavelength, wide-spectrum region, solves the problems of refresh rate, color gamut, grayscale, and cost in the field of color electronic paper, and provides excellent color balance, high contrast, and color brightness, making it a viable alternative display for print media such as newspapers and magazines.

Description

Technical Field

[0001] The invention relates to the technical field of electronic paper, in particular to a color electronic paper with a mesh filter film. Background Art

[0002] There are many technical solutions for color electronic paper, which can be roughly divided into: cholesteric liquid crystal type, filter film type, color particle type, electrowetting type and IMOD solution. In color electronic paper, the display effect depends on the reflection intensity of the five states of black, white and three primary colors. Among the existing display modes, there are direct use of particle scattering or liquid and solid surface reflection, and there are also selective reflection or scattering using birefringence. So far, no matter which display mode is used, it is impossible to obtain the ideal color display state at the same time. The main limitations are color brightness and color reproduction range. In particular, it is difficult to optimize the cost, color gamut, grayscale and refresh time.

[0003] Color cholesteric liquid crystal electronic paper uses three layers of superposition display to achieve full-color display. The principle of this technical solution is as follows: Cholesteric liquid crystal materials have unique selective reflection characteristics. By adjusting the ratio of the chiral components of cholesteric liquid crystals, liquid crystals with different pitches can be obtained. By selecting appropriate materials, it is possible to reflect red, green, and blue wavelengths of light. These three lights are used as the three primary colors of additive mixing to achieve full-color display. The main problem is that the red spectrum region is not sufficiently reflected, and it is difficult to obtain a relatively good full-color display. Its advantage is that the blue and green color effects have better brightness. The disadvantage is that the reflectivity of the cholesteric liquid crystal itself is not ideal in the red spectrum region, and the full spectrum, that is, the white state, is not as good as the reflectivity of the electrophoretic display. In particular, the insufficient red brightness needs to be improved urgently.

[0004] Color electronic paper using a filter film is easy to realize technically, and its display principle is basically the same as that of LCD. However, since electronic paper itself has no light source other than ambient light, the transmittance of the filter film is required to be as high as possible in the transmission broad spectrum, otherwise the absorption of the filter film will reduce the light reflectivity or display brightness. At the same time, due to the limitation of the display principle, the sub-pixels of multiple color filters combined into one display pixel must not overlap, which also reduces the number of pixels per unit area. This solution achieves color display at the expense of brightness and resolution. For the display mode with TFT with backlight or active light emission, by increasing the brightness of the backlight or light emission, the abbreviated sub-pixel area can also achieve high brightness, and then achieve high resolution to obtain excellent display effects. For the electronic paper mode, the electronic paper display is achieved by using ambient light, and its color is highly dependent on the ambient light and the reflectivity of the electronic paper. Due to the limitation of the ambient light brightness, the color gamut range of the filter film type color electronic paper is theoretically very narrow, and it is difficult to further optimize it in terms of process or material. Therefore, many manufacturers and research institutions are committed to developing electronic paper technology in which the pixels themselves have the ability to reflect colored light and can achieve color display without color filters.

[0005] In addition to cholesteric liquid crystal electronic paper, other technologies that do not require color filters include lateral electrophoresis, inverse emulsion electrophoresis, electrowetting, interferometric modulation, photonic crystal display, and electrochromic display. However, these technologies are also limited by the reflectivity of the electronic paper mode itself. In fact, the effect of color electronic paper is still far from the expected goal. The main reason is that the performance of the three primary colors of a single material is unbalanced. Whether it is additive or subtractive color mixing corresponding to the current sub-pixel structure, it is impossible to efficiently utilize the color light and faithfully reproduce the color.

[0006] Among the research and development directions of many manufacturers, color electronic paper with relatively good comprehensive performance includes electrophoretic type composed of multi-color particles and three-dimensional mixed color type. The existing electrophoretic type composed of multi-color particles has poor blue, green and color reproduction, long refresh time, poor driving stability and repeatability, especially in a single pixel, the number of color particles increases, and the waveform changes sensitively under the action of the electric field; in addition, the development of new color particles is difficult and the cycle is long. The two-component liquid crystal box manufacturing process of three-dimensional mixed color color electronic paper is difficult, and the actual application cost is still high. In order to obtain wider applications, it is very necessary to invent a new color electronic paper mode to comprehensively solve the problems of refresh rate, color gamut, grayscale and cost. Summary of the invention

[0007] In view of this, the present invention provides a color electronic paper with a mesh filter film that can make up for the shortcoming of low reflectivity of cholesteric liquid crystal in the long-wave broad spectrum region, solve the refresh rate, color gamut, grayscale and cost problems in the field of color electronic paper, has excellent color balance, high contrast and color brightness, and can be used as an alternative display for paper media such as newspapers and magazines to solve the above problems.

[0008] A color electronic paper with a mesh filter film comprises a first cholesteric liquid crystal structure unit, a second cholesteric liquid crystal structure unit, a mesh filter film and a black-and-white switching layer unit; the first cholesteric liquid crystal structure unit and the second cholesteric liquid crystal structure unit are stacked or arranged in parallel, the black-and-white switching layer unit is located below the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit, and the mesh filter film is located between the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit and the black-and-white switching layer unit.

[0009] Furthermore, the first cholesteric liquid crystal structure unit is stacked on top of the second cholesteric liquid crystal structure unit; the first cholesteric liquid crystal structure unit includes, from top to bottom, a first upper film substrate, a first upper electrode, a first upper orientation film, a first liquid crystal layer, a first lower orientation film, a first lower electrode and a first lower film substrate; the second cholesteric liquid crystal structure unit includes, from top to bottom, a second upper film substrate, a second upper electrode, a second upper orientation film, a second liquid crystal layer, a second lower orientation film, a second lower electrode and a second lower film substrate; the black and white switching layer unit includes, from top to bottom, a third upper film substrate, a common electrode, an electrophoretic layer, an array electrode and a third lower film substrate.

[0010] Furthermore, the first lower film substrate and the second upper film substrate are the same intermediate film substrate.

[0011] Furthermore, the first cholesteric liquid crystal structure unit and the second cholesteric liquid crystal structure unit are arranged in parallel in the same plane; the mesh filter film is located below the first cholesteric liquid crystal structure unit, and an OC layer is arranged below the second cholesteric liquid crystal structure unit; the black and white switching layer unit includes a first black and white switching layer module and a second black and white switching layer module; the first black and white switching layer module is located below the mesh filter film, and the second black and white switching layer module is located below the OC layer.

[0012] Furthermore, the first cholesteric liquid crystal structure unit includes, from top to bottom, a fourth upper film substrate, a third upper electrode, a third upper orientation film, a third liquid crystal layer, a third lower orientation film, a third lower electrode, and a fourth lower film substrate; the second cholesteric liquid crystal structure unit includes, from top to bottom, a fifth upper film substrate, a fourth upper electrode, a fourth upper orientation film, a fourth liquid crystal layer, a fourth lower orientation film, a fourth lower electrode, and a fifth lower film substrate; the first black and white switching layer module includes, from top to bottom, a sixth upper film substrate, a first common electrode, a first electrophoretic layer, a first sub-pixel active array electrode, and a sixth lower film substrate; the second black and white switching layer module includes, from top to bottom, a seventh upper film substrate, a second common electrode, a second electrophoretic layer, a second sub-pixel active array electrode, and a seventh lower film substrate.

[0013] Further, the fourth upper film substrate and the fifth upper film substrate are the same first common upper film substrate, the fourth lower film substrate and the fifth lower film substrate are the same first common lower film substrate, the third upper orientation film and the fourth upper orientation film are the same common upper orientation film, and the third lower orientation film and the fourth lower orientation film are the same common lower orientation film.

[0014] Furthermore, the sixth upper film substrate and the seventh upper film substrate are the same second common upper film substrate, the sixth lower film substrate and the seventh lower film substrate are the same second common lower film substrate, the first common electrode and the second common electrode are the same third common electrode, and the first electrophoretic layer and the second electrophoretic layer are the same common electrophoretic layer.

[0015] Furthermore, there is a first gap between the third upper electrode and the fourth upper electrode, a second gap between the third lower electrode and the fourth lower electrode, a third gap between the first sub-pixel active array electrode and the second sub-pixel active array electrode, and an isolation block between the third liquid crystal layer and the fourth liquid crystal layer.

[0016] Furthermore, a plurality of micro-holes are provided on the mesh filter film, a frame is provided on the outer side of the mesh filter film, and the shape of the micro-holes is a regular hexagon, a circle or a square.

[0017] Furthermore, the pore size of the micropores is 1-2 microns.

[0018] Compared with the prior art, the color electronic paper with a mesh filter film of the present invention comprises a first cholesteric liquid crystal structure unit, a second cholesteric liquid crystal structure unit, a mesh filter film and a black-and-white switching layer unit; the first cholesteric liquid crystal structure unit and the second cholesteric liquid crystal structure unit are stacked or arranged in parallel, the black-and-white switching layer unit is located below the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit, and the mesh filter film is located between the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit and the black-and-white switching layer unit. In this way, the disadvantage of low reflectivity of cholesteric liquid crystal in the long-wave and wide-spectrum region can be compensated, the refresh rate, color gamut, grayscale and cost issues in the field of color electronic paper can be solved, and the display has excellent color balance, high contrast and color brightness, and can be used as a substitute display for paper media such as newspapers and magazines. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The embodiments of the present invention are described below in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 This is a schematic diagram of the overall structure of the first embodiment of the color electronic paper with a mesh filter film provided by the present invention.

[0021] Figure 2 for Figure 1 Schematic diagram of the specific structure.

[0022] Figure 3 This is a schematic diagram of the overall structure of the second embodiment of the color electronic paper with a mesh filter film provided by the present invention.

[0023] Figure 4 for Figure 3 Schematic diagram of the specific structure.

[0024] Figure 5 This is a schematic diagram of a first embodiment of a mesh filter film in a color electronic paper with a mesh filter film provided by the present invention.

[0025] Figure 6This is a schematic diagram of a second embodiment of the mesh filter film in the color electronic paper with the mesh filter film provided by the present invention.

[0026] Figure 7 This is a schematic diagram of a third embodiment of the mesh filter film in the color electronic paper with the mesh filter film provided by the present invention. DETAILED DESCRIPTION

[0027] The specific embodiments of the present invention are further described in detail below based on the accompanying drawings. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the protection scope of the present invention.

[0028] Please refer to Figures 1 to 4 The color electronic paper with a mesh filter film provided by the present invention includes a first cholesteric liquid crystal structure unit 1, a second cholesteric liquid crystal structure unit 2, a mesh filter film 3 and a black and white switching layer unit 4.

[0029] The first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are stacked or arranged in parallel, the black and white switching layer unit 4 is located below the first cholesteric liquid crystal structure unit 1 or the second cholesteric liquid crystal structure unit 2, and the mesh filter film 3 is located between the first cholesteric liquid crystal structure unit 1 or the second cholesteric liquid crystal structure unit 2 and the black and white switching layer unit 4.

[0030] The black-and-white switching layer unit 4 is an electronic paper capable of realizing black-and-white grayscale display, such as electrophoretic electronic paper, electrowetting electronic paper, and liquid crystal electronic paper.

[0031] Please refer to Figure 1 In the first embodiment of the color electronic paper with a mesh filter film provided by the present invention, the first cholesteric liquid crystal structure unit 1 is stacked on the second cholesteric liquid crystal structure unit 2.

[0032] Please refer to Figure 2 The first cholesteric liquid crystal structure unit 1 includes, from top to bottom, a first upper film substrate 8, a first upper electrode 13, a first upper orientation film 19, a first liquid crystal layer 23, a first lower orientation film 20, a first lower electrode 14 and a first lower film substrate.

[0033] The second cholesteric liquid crystal structure unit 2 includes, from top to bottom, a second upper film substrate, a second upper electrode 15 , a second upper alignment film 21 , a second liquid crystal layer 24 , a second lower alignment film 22 , a second lower electrode 16 and a second lower film substrate 10 .

[0034] In this embodiment, the first lower film substrate and the second upper film substrate are the same intermediate film substrate 9, which can reduce one film substrate, reduce the distance between the first cholesteric liquid crystal layer 23 and the second liquid crystal layer 24, and reduce the phase difference.

[0035] The black-and-white switching layer unit 4 includes, from top to bottom, a third upper film substrate 11 , a common electrode 17 , an electrophoretic layer 25 , an array electrode 18 , and a third lower film substrate 12 .

[0036] Please refer to Figure 3 In the second embodiment of the color electronic paper with mesh filter provided by the present invention, the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are arranged side by side in the same plane, the mesh filter 3 is located below the first cholesteric liquid crystal structure unit 1, and an OC layer (over coating, transparent protective layer) 7 is arranged below the second cholesteric liquid crystal structure unit 2. The black and white switching layer unit includes a first black and white switching layer module 5 and a second black and white switching layer module 6. The first black and white switching layer module 5 is located below the mesh filter 3, and the second black and white switching layer module 6 is located below the OC layer 7.

[0037] Please refer to Figure 4 The first cholesteric liquid crystal structure unit 1 includes, from top to bottom, a fourth upper film substrate, a third upper electrode 15, a third upper alignment film, a third liquid crystal layer 24, a third lower alignment film, a third lower electrode 16, and a fourth lower film substrate.

[0038] The second cholesteric liquid crystal structure unit 2 includes, from top to bottom, a fifth upper film substrate, a fourth upper electrode 13, a fourth upper alignment film, a fourth liquid crystal layer 23, a fourth lower alignment film, a fourth lower electrode 14, and a fifth lower film substrate.

[0039] In this embodiment, the fourth upper film substrate and the fifth upper film substrate are the same first common upper film substrate 27, the third upper orientation film and the fourth upper orientation film are the same common upper orientation film 30, the third lower orientation film and the fourth lower orientation film are the same common lower orientation film 31, and the fourth lower film substrate and the fifth lower film substrate are the same first common lower film substrate 28.

[0040] A first gap 26 is provided between the third upper electrode 15 and the fourth upper electrode 13 , and a second gap 40 is provided between the third lower electrode 16 and the fourth lower electrode 14 .

[0041] A spacer 29 is disposed between the third liquid crystal layer 24 and the fourth liquid crystal layer 23 .

[0042] The first black-white switching layer module 5 includes, from top to bottom, a sixth upper film substrate, a first common electrode, a first electrophoretic layer, a first sub-pixel active array electrode 33 and a sixth lower film substrate.

[0043] The second black-white switching layer module 6 includes, from top to bottom, a seventh upper film substrate, a second common electrode, a second electrophoretic layer, a second sub-pixel active array electrode 32 and a seventh lower film substrate.

[0044] In this embodiment, the sixth upper film substrate and the seventh upper film substrate are the same second common upper film substrate 11, the first common electrode and the second common electrode are the same third common electrode 17, the first electrophoretic layer and the second electrophoretic layer are the same common electrophoretic layer 25, and the sixth lower film substrate and the seventh lower film substrate are the same second common lower film substrate 12.

[0045] There is a third gap 41 between the first sub-pixel active array electrode 33 and the second sub-pixel active array electrode 32. The first sub-pixel active array electrode 33 corresponds to the first cholesteric liquid crystal structure unit 1, and the second sub-pixel active array electrode 32 corresponds to the second cholesteric liquid crystal structure unit 2.

[0046] Please refer to Figure 5 A plurality of micropores are provided on the mesh filter film 3. In the first embodiment, the micropores are regular hexagonal holes 34. A frame 36 is provided on the outer side of the mesh filter film 3. A plurality of edge holes 35 are provided on the mesh filter film 3 near the frame 36. A filter film 37 is provided between the regular hexagonal holes 34 or the edge holes 35.

[0047] Please refer to Figure 6 In the second embodiment, the mesh filter film 3 is provided with a plurality of circular holes 38 .

[0048] Please refer to Figure 7 In the second embodiment, the mesh filter film 3 is provided with a plurality of square holes 39 .

[0049] The following is a description of the working process of the color electronic paper with mesh filter film of the present invention.

[0050] The first cholesteric liquid crystal structure unit 1, the second cholesteric liquid crystal structure unit 2 and the black-and-white switching layer unit 4 have independent driving units. The mesh filter film 3 and the black-and-white switching layer unit 4 are partially or completely combined into a sub-pixel to display a primary color. The first cholesteric liquid crystal structure unit 1, the second cholesteric liquid crystal structure unit 2 and the unit 4 are combined into two other sub-pixels to display the other two primary colors. After the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are applied with an electrical signal, the colored light disappears to form a transparent layer, or after the electrical signal is applied, the transparent layer disappears to form a corresponding colored layer; the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 have the same corresponding reflected light flux or absorbed light flux, and the reflected light flux or absorbed light flux is respectively consistent with the mesh filter film 3 structure, but the wavelength is different. In the mesh filter film 3, micropores are provided, and the bottom area of ​​the micropores is equal to the side area of ​​the micropores. The filter film 37 can selectively pass light of a single wavelength or a certain spectral region, and absorb light of other spectral regions.

[0051] like Figure 1As shown, a schematic diagram of a pixel structure in which the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are overlapped and distributed, the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are in different layers, not only the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are overlapped and distributed, but also the black and white switching layer corresponds to the overlapping distribution form and takes an undivided shape, that is, the edges and contours are the same. Here, the mesh filter film can correspond to the entire pixel or a part of the pixel. Figure 1 The pixel structure is divided into: the first cholesteric liquid crystal structure unit 1 is a blue sub-pixel, the second cholesteric liquid crystal structure unit 2 is a green sub-pixel, or the first cholesteric liquid crystal structure unit 1 is a green sub-pixel, the second cholesteric liquid crystal structure unit 2 is a blue sub-pixel; the mesh filter film is a red sub-pixel. According to the material properties, the sub-pixel with high focal conic transmittance is usually placed on the upper layer. In this embodiment, the transmittance of the blue cholesteric liquid crystal layer is high, and it is preferred to set the first cholesteric liquid crystal structure unit 1 to be blue. Figure 3 As shown, it is a schematic diagram of a pixel structure in which a first cholesteric liquid crystal structure unit 1 and a second cholesteric liquid crystal structure unit 2 are arranged in parallel, and the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are in the same layer. Figure 3 The pixel structure is divided into: the first cholesteric liquid crystal structure unit 1 is a blue sub-pixel, the second cholesteric liquid crystal structure unit 2 is a green sub-pixel, or the first cholesteric liquid crystal structure unit 1 is a green sub-pixel, the second cholesteric liquid crystal structure unit 2 is a blue sub-pixel; the mesh filter film is a red sub-pixel. Figure 3 The pixel structure in the display can be freely set with sub-pixel colors without affecting the display effect. The division of the black-and-white switching layer unit 4 corresponds to the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 respectively. The mesh filter film 3 can correspond to one of the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2, or both at the same time, or can be an intermediate state of the above distribution.

[0052] The liquid crystal layer can be left-handed or right-handed cholesteric liquid crystal, and the thickness of the liquid crystal layer is 2-6 microns.

[0053] The thickness of each of the above-mentioned film substrates is less than or equal to 0.2 mm.

[0054] The mesh filter film corresponding to this structure can be Figure 5 The regular hexagonal hole (the side length of the hole is 1 micron, and the thickness of the filter film is about 0.144 microns), Figure 6 The circular hole (the hole radius is 1 micron, and the thickness of the filter film is 0.5 micron), Figure 7 The square hole (the side length of the hole is 1 micron, and the thickness of the filter film is 0.25 micron). The entire pixel array can use a continuous mesh filter film or it can be divided according to the pixel.

[0055] In the second embodiment, the parallel pixel structure can reduce the manufacturing process of one cholesteric liquid crystal structure unit, greatly reducing the manufacturing cost, but the manufacturing of two cholesteric liquid crystal structure units requires special processes. The benefit is that the focal conic state transmittance is increased, and the thickness of the display device is greatly reduced. The mesh filter film corresponding to this structure is set with the same setting as in Example 1, which can be Figure 5 The regular hexagonal hole (the side length of the hole is 1 micron, and the thickness of the filter film is about 0.144 microns), Figure 6 The circular hole (the hole radius is 1 micron, and the thickness of the filter film is 0.5 micron), Figure 7 The pixel array can use a continuous mesh filter film, or it can be divided according to pixels. The pixel array can use a continuous mesh filter film, or it can be divided according to the sub-pixels of the first cholesteric liquid crystal structure unit 1 or the second cholesteric liquid crystal structure unit 2.

[0056] In another embodiment, a single pixel is provided that uses two kinds of mesh filter films, red and green, and a combination of a blue cholesteric liquid crystal structure unit. Alternatively, a single pixel uses two kinds of mesh filter films, red and blue, and a combination of a green cholesteric liquid crystal structure unit. Alternatively, a single pixel uses three kinds of mesh filter films, red, green and blue, retains the black and white switching layer, removes the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2, and is similar to the existing filter film type electrophoretic color electronic paper, and its black and white display state is better than the existing technology.

[0057] In the above embodiments, all the components of the electronic paper are not listed one by one, and only the structure of a single pixel is given. Parts well known to people in the field, such as interlayer spacing materials, sealing parts, liquid crystal molecule arrangement, driving arrays and electrode leads, are ignored here, which has no impact on the understanding of the present invention.

[0058] The specific processing technology is basically the same as that of the first cholesteric liquid crystal structure unit 1, the second cholesteric liquid crystal structure unit 2 and the common TN and STN liquid crystal displays. The difference is that: on the surface of the substrate with the ITO transparent electrode layer attached, a layer of PI vertical alignment film is formed, and its thickness is controlled to be about 400 angstroms, and the thickness error is allowed to be within ±100 angstroms; the PI vertical alignment material uses Nissan Chemical's SE1211 or other similar vertical alignment materials, and the solid content of the diluent is adjusted to 5% during coating, and its error range is 0.1%; the blue cholesteric liquid crystal material uses DIC's RDP-99965ChBZ1, and the green cholesteric liquid crystal material uses a mixture of RDP-99965ChBZ1 (70%) and RDP-99794 (30%). According to the difference in the reflection intensity of the liquid crystal selective reflection, it is necessary to appropriately adjust the liquid crystal layer thickness parameters to achieve the best color display effect. The electrode uses a transparent electrode, such as the common ITO transparent electrode, or an electrode made of PEDOT organic material or AgNW (silver nanowire). The thickness of the substrate is less than 0.3 mm, which can achieve the best color mixing effect. The thinner the substrate, the better the color mixing effect.

[0059] The mesh filter film 3 uses red mesh filter film materials, specifically: red pigment (5-8%, producing red color), photopolymerizable compound (5-8%, each monomer is composed of multiple functional groups, which can react with photoinitiator quickly to form crosslinking to resist weak alkali solution corrosion after light exposure), resin (5-8%, helping the dispersion of pigment and adhesion to glass substrate and providing mechanical strength of color photoresist), photoinitiator (0.2-0.6%, which can quickly form free radicals and ion free radicals when exposed to light), dispersant (5-8%, making pigment wet and dispersed), solvent (67.2-79.7%, determining viscosity and coating properties) and silane coupling agent (0.1-0.2%, increasing bonding strength with substrate). Anthraquinone is selected as the red pigment because it has high temperature resistance, excellent weather resistance and light stability, and has better dispersibility after treatment.

[0060] Processing process of red mesh filter film: The representative manufacturing method is photolithography. Photolithography is to apply the photosensitive composition prepared from the red coloring composition of the present invention on a transparent substrate, heat and dry (pre-bake), and then irradiate ultraviolet rays through a photomask to perform patterned exposure. After the photocurable compound corresponding to the position of the red resin is cured, the unexposed part is developed with a developer to remove the resin of the regular hexagonal holes, circular holes, square holes, or the combination of the three holes, so that it is fixed to the transparent substrate. The method of applying the red photosensitive composition on a transparent substrate such as glass can be listed, for example, spin coating, roller coating, slit coating, inkjet, etc. The drying conditions of the coating of the photosensitive composition applied on the transparent substrate vary depending on the type of each component, the mixing ratio, etc., and are generally 50-150°C and about 1-15 minutes. This heating treatment is generally called pre-bake. In addition, as the ultraviolet light used in the photocuring of the photosensitive composition, it is preferred to use ultraviolet light of I line, G line, H line or a combination wavelength thereof. As the developing method, for example, a liquid pool method, an immersion method, a spray method, etc. can be cited. After the photosensitive composition is developed, the transparent substrate on which the red mesh filter film is formed is washed with water and dried. A heating treatment is performed at 100-280°C for a predetermined time using a heating device such as a hot plate or an oven, which is also called curing, so that the volatile components of the red mesh filter film are removed while the unreacted photocurable compound of the cured color film of the photosensitive composition is thermally cured. Sometimes it is necessary to apply an OC layer to complete the entire processing process.

[0061] The best display effects of various color displays and black displays are:

[0062] (a) The first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are both in focal conic state, the black-white switching layer unit is black, and the pixel displays black.

[0063] (b) The first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are both in a planar state, the black-white switching layer unit is white, and the pixel displays white.

[0064] (c) The first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are both in focal conic state, the black-white switching layer unit is white, and the pixel displays red.

[0065] (d) The first cholesteric liquid crystal structure unit 1 is in a planar state, the second cholesteric liquid crystal structure unit 2 is in a focal conic state, the black-white switching layer unit is black, and the pixel displays blue.

[0066] (e) The first cholesteric liquid crystal structure unit 1 is in a focal conic state, the second cholesteric liquid crystal structure unit 2 is in a planar state, the black-white switching layer unit is black, and the pixel displays green. The above five states are the basic color states of color electronic paper, and other states can be obtained by mixing colors as needed. Since each structure unit can obtain grayscale, the entire color electronic paper has full color reproduction capability.

[0067] Compared with the prior art, the color electronic paper with a mesh filter film of the present invention comprises a first cholesteric liquid crystal structure unit 1, a second cholesteric liquid crystal structure unit 2, a mesh filter film 3 and a black-and-white switching layer unit 4; the first cholesteric liquid crystal structure unit 1 and the second cholesteric liquid crystal structure unit 2 are stacked or arranged in parallel, the black-and-white switching layer unit 4 is located below the first cholesteric liquid crystal structure unit 1 or the second cholesteric liquid crystal structure unit 2, and the mesh filter film 3 is located between the first cholesteric liquid crystal structure unit 1 or the second cholesteric liquid crystal structure unit 2 and the black-and-white switching layer unit 4. In this way, the disadvantage of low reflectivity of cholesteric liquid crystal in the long-wave and wide-spectrum region can be compensated, the refresh rate, color gamut, grayscale and cost problems in the field of color electronic paper can be solved, and the display has excellent color balance, high contrast and color brightness, and can be used as a substitute display for paper media such as newspapers and magazines.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent substitution or improvement within the spirit of the present invention is included in the scope of the claims of the present invention.

Claims

1. A color electronic paper with a mesh filter film, characterized in that: The invention comprises a first cholesteric liquid crystal structure unit, a second cholesteric liquid crystal structure unit, a mesh filter film and a black-and-white switching layer unit; the first cholesteric liquid crystal structure unit and the second cholesteric liquid crystal structure unit are stacked or arranged in parallel, the black-and-white switching layer unit is located below the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit, the mesh filter film is located between the first cholesteric liquid crystal structure unit or the second cholesteric liquid crystal structure unit and the black-and-white switching layer unit, a plurality of micropores are opened on the mesh filter film, and filter films are arranged between the micropores, and the filter film can selectively pass light of a single wavelength or a certain spectral region, and absorb light of other spectral regions.

2. The color electronic paper with mesh filter film as claimed in claim 1, characterized in that: The first cholesteric liquid crystal structure unit is stacked on top of the second cholesteric liquid crystal structure unit; the first cholesteric liquid crystal structure unit includes, from top to bottom, a first upper film substrate, a first upper electrode, a first upper orientation film, a first liquid crystal layer, a first lower orientation film, a first lower electrode and a first lower film substrate; the second cholesteric liquid crystal structure unit includes, from top to bottom, a second upper film substrate, a second upper electrode, a second upper orientation film, a second liquid crystal layer, a second lower orientation film, a second lower electrode and a second lower film substrate; the black and white switching layer unit includes, from top to bottom, a third upper film substrate, a common electrode, an electrophoretic layer, an array electrode and a third lower film substrate.

3. The color electronic paper with mesh filter film as claimed in claim 2, characterized in that: The first lower film substrate and the second upper film substrate are the same intermediate film substrate.

4. The color electronic paper with mesh filter film as claimed in claim 1, characterized in that: The first cholesteric liquid crystal structure unit and the second cholesteric liquid crystal structure unit are arranged in parallel in the same plane; the mesh filter film is located below the first cholesteric liquid crystal structure unit, and an OC layer is arranged below the second cholesteric liquid crystal structure unit; the black and white switching layer unit includes a first black and white switching layer module and a second black and white switching layer module; the first black and white switching layer module is located below the mesh filter film, and the second black and white switching layer module is located below the OC layer.

5. The color electronic paper with mesh filter film as claimed in claim 4, characterized in that: The first cholesteric liquid crystal structure unit includes, from top to bottom, a fourth upper film substrate, a third upper electrode, a third upper orientation film, a third liquid crystal layer, a third lower orientation film, a third lower electrode, and a fourth lower film substrate; the second cholesteric liquid crystal structure unit includes, from top to bottom, a fifth upper film substrate, a fourth upper electrode, a fourth upper orientation film, a fourth liquid crystal layer, a fourth lower orientation film, a fourth lower electrode, and a fifth lower film substrate; the first black and white switching layer module includes, from top to bottom, a sixth upper film substrate, a first common electrode, a first electrophoretic layer, a first sub-pixel active array electrode, and a sixth lower film substrate; the second black and white switching layer module includes, from top to bottom, a seventh upper film substrate, a second common electrode, a second electrophoretic layer, a second sub-pixel active array electrode, and a seventh lower film substrate.

6. The color electronic paper with mesh filter film as claimed in claim 5, characterized in that: The fourth upper film substrate and the fifth upper film substrate are the same first common upper film substrate, the fourth lower film substrate and the fifth lower film substrate are the same first common lower film substrate, the third upper orientation film and the fourth upper orientation film are the same common upper orientation film, and the third lower orientation film and the fourth lower orientation film are the same common lower orientation film.

7. The color electronic paper with mesh filter film as claimed in claim 5, characterized in that: The sixth upper film substrate and the seventh upper film substrate are the same second common upper film substrate, the sixth lower film substrate and the seventh lower film substrate are the same second common lower film substrate, the first common electrode and the second common electrode are the same third common electrode, and the first electrophoretic layer and the second electrophoretic layer are the same common electrophoretic layer.

8. The color electronic paper with mesh filter film as claimed in claim 5, characterized in that: There is a first gap between the third upper electrode and the fourth upper electrode, a second gap between the third lower electrode and the fourth lower electrode, a third gap between the first sub-pixel active array electrode and the second sub-pixel active array electrode, and an isolation block between the third liquid crystal layer and the fourth liquid crystal layer.

9. The color electronic paper with mesh filter film as claimed in claim 1, characterized in that: A frame is arranged on the outer side of the mesh filter film, and the shape of the microholes is a regular hexagon, a circle or a square.

10. The color electronic paper with mesh filter film as claimed in claim 9, characterized in that: The pore size of the micropores is 1-2 microns.

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