Fluorescent electronic paper

Abstract

The invention discloses fluorescent electronic paper. A plurality of color cells; the color bag internally comprises liquid, charged particles and fluorescent particles; the charged particles are suspended in the liquid; the fluorescent particles are suspended in the liquid; the fluorescent particles can absorb energy of an external light source, store the energy and emit light by releasing the energy. The fluorescent particles are not charged and are uniformly distributed in the liquid. The average diameter of the fluorescent particles is smaller than the average diameter of the charged particles.

Description

Technical Field

[0001] The present application belongs to the field of display technology, and specifically relates to a fluorescent electronic paper. Background Art

[0002] E-paper ink screen is a display screen made by electrophoretic display technology. It achieves the effect of displaying images by driving the electronic paper particles by continuously applying the electric field of the driving waveform to each pixel point through the driver IC chip. E-paper ink screen display has the characteristics of ultra-low power consumption, low-frequency display and power saving, and has a wide application market in price tags, advertising signs and bus stops.

[0003] In the prior art, two-color electronic paper is to encapsulate black and white charged particles in the same capsule structure, and three-color electronic paper is to encapsulate three colors of charged particles such as black, white, red or black, white, yellow in the same microcup structure, and control the lifting and moving of black, white, red particles with different charges by an external electric field to display black, white, red or black, white, yellow. However, such color combinations obviously cannot meet the demand for richer color display.

[0004] The two-color electronic paper includes black and white charged particles, black and white two-color electronic ink microcapsules and a preparation method, including preparing electrically neutral polymethyl methacrylate carbon black electrophoretic particles; preparing polystyrene microspheres by emulsion polymerization; hydrolyzing tetrabutyl titanate to prepare polystyrene titanium dioxide core-shell structure particles; coating polymethyl methacrylate to prepare negatively charged polymethyl methacrylate titanium dioxide polystyrene double-shell structure electrophoretic particles; and mixing black and white particles in a certain proportion to prepare an electrophoretic solution.

[0005] Traditional electronic paper cannot emit light by itself. In the absence of light, the graphics cannot be viewed. In order to enhance the display under no-light conditions, existing technologies point out that a fluorescent layer is added above the ink sac in the electronic paper film. However, the addition of this fluorescent layer reduces the light penetration and affects the normal display. When there is no light and the fluorescence is emitted, the enhanced performance of the illumination effect in the ink sac is not outstanding.

[0006] Glossary:

[0007] EPD is the abbreviation of "electronic paper display" in English, which means electronic paper display in Chinese.

[0008] TFT is the abbreviation of "Thin Film Transistor" in English, and its Chinese meaning is (Thin Film Field Effect Transistor); in this application, it means that each pixel on the display is driven by a thin film transistor integrated therein, so that the screen information can be displayed at high speed, high brightness and high contrast.

[0009] ITO is the abbreviation of "Indium Tin Oxide" in English, and its Chinese meaning is indium tin oxide. In this application, electronic paper ITO refers to the conductive film layer material of the transparent conductive film shielding glass mainly being ITO (indium tin oxide semiconductor) film. Summary of the invention

[0010] The technical problem to be solved by the present invention is the visibility problem of electronic paper in a short or long period of time without light.

[0011] The present application achieves a short or long display without light by adding fluorescent particles that can store energy and slowly release energy to the above-mentioned color capsules. By adding uncharged particles with smaller diameters, the existing electronic driving mode can be unchanged, so that electronic paper of various colors can have luminous properties. Charged particles can also be made into charged fluorescent particles, and different particles can be selected to have luminous properties. By changing the driving mode, the displayed pattern can have the performance of fluorescence enhancement of some colors.

[0012] A fluorescent electronic paper comprises: a plurality of color capsules; the color capsules contain liquid, charged particles, and fluorescent particles; the charged particles are suspended in the liquid; the fluorescent particles are suspended in the liquid; the fluorescent particles can absorb energy from an external light source, store the energy, and emit light by releasing the energy.

[0013] It can be that the fluorescent particles are uncharged and are evenly distributed in the liquid.

[0014] It may be that the average diameter of the fluorescent particles is smaller than the average diameter of the charged particles.

[0015] It may be that the average diameter of the fluorescent particles is equal to the average diameter of the charged particles, and the fluorescent particles are charged.

[0016] It may be that the fluorescent particles are charged fluorescent particles, the charged fluorescent particles are white, and the charged particles are black.

[0017] It can be that the fluorescent particles are charged fluorescent particles, and the charged particles are black; the charged fluorescent particles include color 1 charged fluorescent particles and color 2 charged fluorescent particles.

[0018] It can be that the charged fluorescent particles of color 1 are white; and the charged fluorescent particles of color 2 are red.

[0019] It can be that the charged fluorescent particles of color 1 are white; and the charged fluorescent particles of color 2 are yellow.

[0020] Alternatively, the fluorescent particles may be wrapped with a waterproof film.

[0021] The fluorescent particles may be polystyrene fluorescent microspheres.

[0022] A fluorescent electronic paper display device comprises any one of the fluorescent electronic papers mentioned above.

[0023] One of the beneficial effects of the technical solution in the present application is that the fluorescent particles are arranged in the color capsule, and there is no need to set a fluorescent layer, which reduces the light loss of the process and maximizes the fluorescent effect.

[0024] One of the beneficial effects of the technical solution in the present application is that the fluorescent particles are evenly distributed in the liquid, ensuring uniform fluorescent effect.

[0025] One of the beneficial effects of the technical solution in the present application is that the average diameter of the fluorescent particles is smaller than the average diameter of the charged particles, and the presence of the fluorescent particles does not affect the movement of the charged particles.

[0026] One of the beneficial effects of the technical solution in the present application is that the fluorescent particles are charged and directly possess the characteristics of fluorescence and charged particles.

[0027] One of the beneficial effects of the technical solution in the present application is that the charged fluorescent particles are white; the charged particles are black; and white fluorescence can have a better fluorescence effect.

[0028] One of the beneficial effects of the technical solution in the present application is that the charged fluorescent particles include color 1 charged fluorescent particles and color 2 charged fluorescent particles, which can be combined with multi-color fluorescence to output fluorescence of different colors.

[0029] One of the beneficial effects of the technical solution in the present application is that the combination of white and red charged fluorescent particles, and the combination of white and yellow charged fluorescent particles can output fluorescence of different colors.

[0030] One of the beneficial effects of the technical solution in the present application is that the outside of the fluorescent particles is wrapped with a waterproof film, which can better exert the fluorescent effect and maintain the fluorescence time longer.

[0031] One of the beneficial effects of the technical solution in the present application is that the fluorescent particles are polystyrene fluorescent microspheres, which provide the possibility of multi-color fluorescent particles and are easily available and suitable for mass applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the structure of fluorescent electronic paper;

[0033] Figure 2 It is a schematic diagram of the structure of fluorescent electronic paper;

[0034] Figure 3 It is a schematic diagram of the color capsule structure of fluorescent electronic paper;

[0035] Figure 4 It is a schematic diagram of the color capsule structure of fluorescent electronic paper;

[0036] Figure 5 It is a schematic diagram of the color capsule structure of fluorescent electronic paper;

[0037] Figure 6 This is a schematic diagram of the color capsule structure of fluorescent electronic paper. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0039] It should be noted that the following is a description of the preferred embodiments of the present application, which does not constitute any limitation to the present application. The description of the preferred embodiments of the present application is only an explanation of the general principles of the present application. The embodiments described in this application are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0040] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and technical features numbered with Arabic numerals 1, 2, 3, etc., and numbers such as "A" and "B", are only used for descriptive purposes and are only for the convenience of explanation, and do not represent a sequential relationship in time or space; they cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", and numbered with Arabic numerals 1, 2, 3, etc. may explicitly or implicitly include one or more of the features. In the description of the present application, “several” means two or more than two, unless otherwise clearly and specifically defined.

[0041] The luminous time of fluorescent powder varies according to its type. After absorbing light energy, light-storage luminous powder can continue to glow in the dark for several hours to more than ten hours, usually the first 1 to 2 hours is the brightest period. Short-term luminous powder, such as zinc sulfide luminous powder, can glow for 0.5 to 1 hour after absorbing light for 3-15 seconds. Long-term luminous powder can emit light in the dark for more than 12 hours by absorbing and storing visible light for 10-20 minutes.

[0042] The luminescence principle of phosphor is mainly to absorb the energy of natural light, sunlight or ultraviolet light, store it, and then slowly release the energy in the dark to emit light. This material has the characteristics of high brightness, long afterglow time, light resistance, aging resistance and good chemical stability. It is non-toxic, non-radiative, and non-explosive, and is a green and environmentally friendly material.

[0043] Phosphors are widely used in a variety of media such as coatings, inks, plastics, ceramics, fibers, etc. to make luminous signs, luminous glass, luminous ceramics, clocks and watches used at night, telephone keys, buttons, field instruments, etc. In addition, phosphors are also used in clothing printing, power switches, mobile phone cases, building decoration, and fire emergency escape systems.

[0044] The ability of phosphor to absorb radiation is related to the degree of dispersion of phosphor, so its particle size has a great influence on the luminous brightness. The particle size of calcium halophosphate phosphor is determined by the particle size of raw material CaHPO4. Therefore, by obtaining crystal CaHPO4 of a certain size and lattice, the particle size of phosphor can be controlled to a certain size (5-10μ), thereby obtaining high luminous brightness. In the present application, the particle size range of phosphor particles, i.e., small fluorescent particles, can be in various situations.

[0045] Among the rare earth tri-color phosphors, red powder is europium-activated yttrium oxide (Y2O3:Eu), green powder is cerium- and terbium-activated aluminate (MgAl 11O19:Ce,Tb), and blue powder is low-valent europium-activated barium magnesium aluminate (BaMg2Al 16O27:Eu). Mixing the three powders in a certain proportion can produce different color temperatures (2700-6500K), and the corresponding lamps have a luminous efficiency of 80-100lm / W and a color rendering index of 85-90. Generally speaking, the higher the green powder content and the lower the blue powder content, the higher the luminous efficiency of the lamp tube. In addition, as the blue powder increases, the color temperature increases; as the red powder increases, the color temperature decreases.

[0046] The matrix and activation materials of the three base color powders are different, but the key to their luminescence lies in the rare earth activation materials (europium, cerium, terbium, etc.), which utilize the transition of the outer layer ions (D→F) of rare earth metals to emit light.

[0047] Tri-color fluorescent lamps using rare earth tri-color phosphors have many outstanding advantages. However, rare earth raw materials are expensive, resulting in high cost of tri-color lamps, which limits the development of tri-color lamps. Reducing the tube diameter or using new coating technology to reduce the amount of tri-color powder, and using other cheap color powders to partially replace one or two rare earth tri-color powders, can also produce fluorescent lamps with high light efficiency and high color rendering, but the light decay may be a little larger.

[0048] The luminescence of calcium halophosphate phosphor is activated by the activators antimony (Sb) and manganese Mn. The activator atoms occupy the position of calcium atoms in the lattice. This material has a sensitization phenomenon: when the activator Sb absorbs the excitation energy, it releases part of the energy in the form of light radiation, and the other part is transferred to Mn in the so-called resonance transfer process, causing Mn to generate its own radiation. Therefore, the total radiation depends on the characteristics of the two activators, and changes with the change of its ratio, and also depends on the ratio of fluorine and chlorine. If the manganese content is increased in the Sb-activated calcium halophosphate, the orange-yellow radiation will increase, while the blue radiation will be reduced accordingly. By using the above phenomenon, calcium halophosphate phosphors with different color temperatures can be obtained by simply changing the Mn content.

[0049] In real life, people use the long-term glowing property of luminous powder to make weak lighting sources. It has special uses in the military. This material is applied to aviation instruments, clocks, windows, various switch signs on machines, door handles, etc. It can also be pressed together with various translucent plastics to form various symbols, parts, and supplies (such as power switches, sockets, fishing hooks, etc.). After being exposed to light, these luminous parts continue to glow at night or when they get up after an unexpected power outage or lightning, so that people can identify the surrounding direction and bring convenience to work and life. Adding ultrafine particles of luminous materials to textiles makes the colors more vivid. Children wearing luminous textiles can reduce traffic accidents.

[0050] Luminous materials at home and abroad are mainly made of ZnS (zinc sulfide), SrS (strontium sulfide) and CaS (calcium sulfide), which emit green and yellow light. However, SrS and CaS materials are easy to deliquesce, which makes it difficult to be widely used. Therefore, the luminous materials on the market are mainly based on ZnS. However, its afterglow time is only 1 to 3 hours, and it is easy to deteriorate and blacken in strong light (such as sunlight), ultraviolet light and humid air, so its application is limited in many fields. Although the ZnS luminous powder co-activated by copper has a long afterglow time, it has infrared quenching phenomenon. Under the irradiation of electric light (containing more red light), the afterglow is quickly extinguished.

[0051] Ordinary phosphor: Ordinary phosphor cannot come into direct contact with water. It will easily clump when exposed to moisture, which will affect the luminescence performance23.

[0052] Waterproof phosphor: Waterproof phosphor is wrapped with a waterproof film and can be used directly with water-based paint without affecting the luminous effect24.

[0053] Blue fluorescent polystyrene microspheres PS microspheres 2um, PS polystyrene microsphere powder (particle size range 20nm to 200um)

[0054] Polystyrene fluorescent microspheres, fluorescently modified polystyrene microspheres red / green / yellow / blue ps fluorescent microspheres 20nm-200um size optional.

[0055] Polystyrene fluorescent microspheres are a high-performance material widely used in medical diagnosis, blood flow measurement, tracing, in vivo imaging, and calibration of imaging instruments and flow cytometers. Their characteristics include high fluorescence intensity, stable performance, and narrow particle size distribution. The particle size of these microspheres can range from 100nm to 500nm, or even larger, and the surface groups and concentrations have been strictly screened. They can be connected to various proteins and are suitable for diagnostic reagents such as immunofluorescence chromatography, meeting the requirements of reagents in terms of sensitivity, linear range, stability, and prevention of non-specific adsorption.

[0056] Characteristics of polystyrene fluorescent microspheres Polystyrene fluorescent microspheres have the following characteristics: High fluorescence intensity: Since the fluorescent molecules are embedded inside the microspheres, the fluorescence signal of these microspheres is more stable. Narrow particle size distribution: The particle size distribution of polystyrene fluorescent microspheres is narrow, but the dispersion is good, which makes them more effective in various applications. The application of polystyrene fluorescent microspheres in displays has not been seen in the prior art.

[0057] like Figure 1 , electronic ink display devices all include electronic paper films. If it is necessary to control the display changes of the electronic paper, a TFT driving component must also be included under the electronic paper film. The electronic paper film and the TFT driving component constitute an electronic module.

[0058] like Figure 3 The electronic paper includes: a plurality of color capsules; the color capsules include liquid, charged particles, and fluorescent particles; the charged particles are suspended in the liquid; the fluorescent particles are suspended in the liquid; the fluorescent particles can absorb energy from an external light source, store the energy, and emit light by releasing the energy.

[0059] like Figure 2 , TFT substrate, can change the distribution of charge, the charged particles in the charged particle color capsule can change the distribution state to achieve different color displays.

[0060] It can be, for example Figure 3 The fluorescent particles are not charged and are evenly distributed in the liquid. The fluorescent particles, i.e., small fluorescent particles, are evenly distributed in the color capsule.

[0061] like Figure 3By adding uncharged fluorescent particles, the fluorescent particles are evenly distributed in the liquid. No matter whether the white particles float up or the black particles float up, the fluorescent particles can receive external light. In the absence of light, they emit light to illuminate the black and white particles. When the black particles float up, the black balls will absorb part of the fluorescence, making the displayed pattern also clearly black and white.

[0062] like Figure 4 In the ink sac of black and white electronic paper, there are black charged particles and white charged particles. The white charged particles are white fluorescent particles, which have color and fluorescence characteristics. Whether the white particles float up or the black particles float up, the white fluorescent particles can receive external light. In the absence of light, they will illuminate the black and white particles. When the black particles float up, the black balls will absorb part of the fluorescence, making the displayed pattern also clear in black and white.

[0063] like Figure 5 , in the ink sac containing two or more particles of different colors. Also adding small particles of fluorescent particles can enhance the display of various colors. Figure 5 It includes black charged particles, white charged particles, red particles and small fluorescent particles, namely fluorescent particles.

[0064] like Figure 6 In the ink sac of the three-color electronic paper, there are black charged particles, white charged particles, and red particles. The white fluorescent particles are white charged particles, which have color and fluorescent characteristics, and are also charged. The red particles are red fluorescent particles, which have color and fluorescent characteristics. Whether the white particles float up or the black particles float up, the white fluorescent particles and the red fluorescent particles can receive external light. In the absence of light, the two fluorescent particles emit light to illuminate, making the displayed pattern brighter.

[0065] It can be, for example Figure 3 The fluorescent particles are not charged, and the fluorescent particles are uniformly distributed in the liquid. The average diameter of the fluorescent particles is smaller than the average diameter of the charged particles.

[0066] It can be, for example Figure 4 , the average diameter of the fluorescent particles is equal to the average diameter of the charged particles, and the fluorescent particles are charged.

[0067] It can be, for example Figure 6 , the fluorescent particles are charged fluorescent particles, the charged fluorescent particles are white, and the charged particles are black.

[0068] It can be, for example Figure 6The fluorescent particles are charged fluorescent particles, and the charged particles are black; the charged fluorescent particles include color 1 charged fluorescent particles and color 2 charged fluorescent particles. The color 1 charged fluorescent particles are white; and the color 2 charged fluorescent particles are red.

[0069] In some other embodiments, the color 1 charged fluorescent particles are white; and the color 2 charged fluorescent particles are yellow.

[0070] In some embodiments, the fluorescent particles are wrapped with a waterproof film to better play the role of the fluorescent particles.

[0071] In some embodiments, the fluorescent particles are polystyrene fluorescent microspheres.

[0072] A fluorescent electronic paper display device comprises any one of the fluorescent electronic papers mentioned above.

[0073] As shown in the accompanying drawings, the above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the invention specification and the accompanying drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fluorescent electronic paper, characterized in that: Comprising: a plurality of color capsules; the color capsules contain liquid, charged particles, and fluorescent particles; The charged particles are suspended in the liquid; The fluorescent particles are suspended in the liquid; The fluorescent particles can absorb energy from an external light source, store the energy, and emit light by releasing the energy.

2. The fluorescent electronic paper according to claim 1, characterized in that: The fluorescent particles are uncharged and are evenly distributed in the liquid.

3. The fluorescent electronic paper according to claim 2, characterized in that: The average diameter of the fluorescent particles is smaller than the average diameter of the charged particles.

4. The fluorescent electronic paper according to claim 1, characterized in that: The average diameter of the fluorescent particles is equal to the average diameter of the charged particles; The fluorescent particles are charged.

5. The fluorescent electronic paper according to claim 1, characterized in that: The fluorescent particles are charged fluorescent particles, and the charged fluorescent particles are white; the charged particles are black.

6. The fluorescent electronic paper according to claim 1, characterized in that: The fluorescent particles are charged fluorescent particles, and the charged particles are black; the charged fluorescent particles include color 1 charged fluorescent particles and color 2 charged fluorescent particles.

7. The fluorescent electronic paper according to claim 6, characterized in that: Including any of the following technical features: TA10: The charged fluorescent particles of color 1 are white; the charged fluorescent particles of color 2 are red; TA20: The charged fluorescent particles of color 1 are white; the charged fluorescent particles of color 2 are yellow.

8. The fluorescent electronic paper according to claim 1, characterized in that: The outside of the fluorescent particles is wrapped by a waterproof film.

9. The fluorescent electronic paper according to claim 6, characterized in that: The fluorescent particles are polystyrene fluorescent microspheres.

10. A fluorescent electronic paper display device, characterized in that: The fluorescent electronic paper comprises the fluorescent electronic paper as described in any one of claims 1 to 9.

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