KR100920233B1 - Method for injecting particles in electrical paper display - Google Patents

Abstract

PURPOSE: A particle injection method of an electronic paper display device is provided to inject particles into only a cell which is a pixel space, not an upper part of a partition, thereby removing spots on an image. CONSTITUTION: A particle injection method of an electronic paper display device comprises the following steps of: charging the first metal plate(20) with a negative electricity; charging positive-charged particles(40) between the first carved patterns(32); forming the first carved patterns in the first metal plate; charging the second metal plate(50) with a positive electricity; and charging negative-charged particles(60) between the second carved patterns(52).

Description

Particle injection method of electronic paper display device {Method for injecting particles in Electrical Paper Display}

The present invention relates to a particle injection method of an electronic paper display element.

In response to the information society that requires a new paradigm today, a great transformation is needed in the way information is delivered and shared. To meet this, technology development of electronic paper, which has the advantage of bending as a flexible display, is being accelerated, and electronic paper technology development is entering a commercial development stage.

Electronic paper is much cheaper to produce than conventional flat panel displays, and since it does not require background lighting or continuous recharging like a normal screen, it can be driven with very little energy, leading to energy efficiency.

In addition, the electronic paper is very sharp, has a wide viewing angle, and has a memory function that does not completely disappear even in the absence of power.

This great advantage makes electronic paper a great candidate for a wide range of applications, such as e-books with paper-like sides and moving illustrations, self-renewable newspapers, reusable paper displays for mobile phones, disposable TV screens and electronic wallpaper. It has a huge potential market.

The technical approach for the electronic paper implementation includes a liquid crystal method, an organic EL, a reflective film reflective display, an electrophoresis, a twist ball, an electrochromic method, and a mechanical reflective light.

In the case of the double twisted ball method, there is no critical threshold due to no voltage threshold in the phase change of the ball.Electrochromic devices are also less chemically stable when the colored layer is exposed to air and moisture, and ions in the electrolyte Due to its diffusion speed, the response speed is slow. Therefore, the technology for implementing an electronic paper display device, which is currently attracting the most attention, is an electronic paper display device using electrophoresis.

The electrophoretic phenomena can be divided into wet and dry methods.

The wet method produced transparent microcapsules containing ink particles of a different color with specific charges and ink particles of different colors with opposite charges and transparent dielectric fluids. When these microcapsules are mixed with a binder and placed between the upper and lower transparent electrodes, and a voltage is applied, characters or images are displayed by the method described above.

However, this wet method has a problem in realizing a video due to the slow response speed of about 100ms due to the viscous resistance of the liquid, and also has a problem in that a large portion of the upper part of the capsule is shielded by a binder or partially consumed so that the light efficiency is relatively low. .

The dry electronic paper display device charges a collision due to enclosing two kinds of particles having different colors and charging characteristics between transparent substrates having electrodes formed on one surface thereof, and applying voltages to the electrodes of the upper and lower panels, thereby causing the particles to collide with each other. The charged particles are formed. Next, the electric field is applied to the particle group charged from the electrodes of the upper and lower plates having different dislocations, and the particles are moved to display an image. In this case, the electronic paper display includes one or more pixels separated from each other by the partition wall.

The dry electronic paper display device is suitable for the realization of a video because the response speed is considerably fast because there is no material having a high viscosity such as liquid in the pixel space.

In such a dry electronic paper display device manufacturing method, the process of injecting particles into the pixel is very important for the stability and uniformity of the image. To this end, the ratio of the absolute amount to which the particles are injected and the relative amount of the particles must be uniform for each pixel.

That is, when the particles of different types of black and white are injected, the absolute amount of particles to be injected into the pixel must be uniform for each pixel, and the relative amount ratio of each of the black and white particles to be injected into the pixel must be uniform for each pixel.

The spray coating method is the most common method of particle injection, in which particles are sprayed in a particle spreader and injected into a cell. Since the spray method is injected at random rather than opposed to a specific cell, the distance between the spray nozzle of the particle applicator and the partition wall of the lower substrate is sprayed apart by several tens of centimeters.

In particular, as shown in FIG. 1, the charged particles sprayed from the nozzle may be laminated on the barrier rib upper surface, in which case there is a problem in that adhesion failure occurs when the barrier rib upper surface and the upper substrate are bonded. To solve this problem, a separate process is required to remove the particles located above the bulkhead.

Another method of injecting charged particles into the cell is to make the charged particles easily reach the inside of the partition by mounting a corona discharger in front of the nozzle.

It sprays negatively charged charged particles using corona discharge and injects them into the cell space separated by the partition wall. At this time, the charged particles are easily attracted by adding a means for applying a positive voltage to the lower electrode or a positive electric field below the substrate. However, even in this case, there is a limit in controlling the injection amount of particles, and when the panel is to be implemented in a large area, when the size of the pixel and the partition increases, the concentration of the particles is concentrated only in the center, resulting in uneven coating of the particles.

In particular, the conventional injection method is a large amount of particles are applied to the cell close to the nozzle of the particle applicator and far away from the nozzle because the distance between the nozzle and the cell of the particle applicator is far apart and the distance between the nozzle and each cell is different There is a problem that a relatively small amount of particles are applied to the cell. That is, there is a problem that the absolute amount of particles injected into each cell is different.

In addition, when there are many kinds of particles, each particle has different physical and chemical properties such as volume, mass, shape, and cohesiveness. Therefore, if the distance between the cell and the nozzle is far or the distance between the cell and the nozzle is different, The relative amount ratio of the injected amount of the various kinds of particles injected also has a different problem for each cell. These problems cause image nonuniformity of the electronic paper display element and cause decisive problems such as spots or spots on the screen, thereby decisively degrading image quality.

The present invention can be injected only into the cell, which is the pixel space, without injecting particles into the upper part of the partition wall. Provide a method.

According to an aspect of the invention, the step of negatively charging the first metal plate on which the first embossed pattern is formed to charge (+) charged particles between the first embossed pattern, the second metal plate on which the second embossed pattern is formed Charging the negatively-charged particles between the second embossed pattern, aligning the first embossed pattern and the second embossed pattern to correspond, and bonding the first embossed pattern and the second embossed pattern to each other; A particle injection method of an electronic paper display element is provided.

First, the first embossed pattern may be formed by stacking a resin layer on a first metal plate, preparing a stamp on which a third embossed pattern is formed, and compressing the stamp on the resin layer.

Here, when the (+) charged particles are black particles formed of carbon black, the (-) charged particles may be white particles formed of titanium oxide, and (+) when the charged particles are white particles formed of titanium oxide The particles may be black particles formed of carbon black.

Meanwhile, the first metal plate and the second metal plate may be formed by stacking electrodes on the substrate.

In addition, the first embossed pattern and the second embossed pattern may be made of polycarbonate (PC), polyethylene terephthalate (PET), polyethersulfone (PES) and polyimide, and in the group consisting of epoxy, urethane and polyester It may be made of any one material selected.

In addition, the step of aligning may be performed using a binocular lens.

In addition, after the aligning step, the method may further include heat treating end portions of the first relief pattern and the second relief pattern.

The particle injection method of the electronic paper display device according to the present invention can be injected only into the cell space, which is the pixel space, without the particles being injected into the upper part of the partition wall. You can improve the image quality by removing spots and spots on the screen.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, an embodiment of a particle injection method of an electronic paper display device according to the present invention will be described in detail with reference to the accompanying drawings. In the following description with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals. And duplicate description thereof will be omitted.

2 is a flowchart illustrating a particle injection method of an electronic paper display device according to an embodiment of the present invention, and FIGS. 3 to 5 are flowcharts illustrating a method of manufacturing a first relief pattern according to an embodiment of the present invention. 6 to 11 are flowcharts illustrating a particle injection method of an electronic paper display device according to an embodiment of the present invention.

3 to 11, the stamp 10, the third embossed pattern 12, the first metal plate 20, the resin layer 30, the first embossed pattern 32, and the (+) charged particles 40. ), A second metal plate 50, a second embossed pattern 52, (-) charged particles 60, and a partition wall 70 are shown.

In this embodiment, the first metal plate 20 on which the first embossed pattern 32 is formed is negatively charged to fill (+) charged particles 40 between the first embossed pattern 32, and the second embossed pattern. The second metal plate 50 having the 52 formed thereon is positively charged to fill the negatively charged particles between the second embossed patterns 52. The first embossed pattern 32 and the second embossed pattern 52 are formed. The particles are injected into the upper part of the partition wall 70 by providing a particle injection method of the electronic paper display device, the method including aligning the corresponding parts and bonding the first and second embossed patterns 32 and 52 to each other. It can be injected only inside the cell, which is the pixel space, and the relative ratio of the particle injected into the cell and the relative ratio of the particle type can be uniform for each cell, so that the image quality can be improved by eliminating spots or spots on the screen. Can be.

First, a method of forming the first relief pattern 32 will be described with reference to FIGS. 3 to 5. 3 to 5 are flowcharts illustrating a method of manufacturing the first relief pattern 32 according to an embodiment of the present invention.

First, as shown in FIG. 3, a stamp 10 having a third embossed pattern 12 is prepared (S20). At this time, the stamp 10 on which the third embossed pattern 12 is formed is subjected to self-assembled monolayer (SAM) coating. When the coating layer is formed by performing SAM coating on the third embossed pattern 12, when the embossed pattern 12 of the stamp 10 is pressed onto the resin layer 30, the resin layer 30 and the stamp ( 10) can be easily separated

Next, as shown in FIG. 4, after the resin layer 30 is laminated on the first metal plate 20 (S10), as shown in FIG. 5, the stamp 10 is attached to the resin layer 30. The third embossed pattern 12 may be compressed to form an intaglio pattern corresponding to the third embossed pattern 12, and a first embossed pattern 32 may be formed between the intaglio patterns (S30).

On the other hand, when using a thermosetting epoxy material as the resin layer 30, in order to be able to form the first embossed pattern 32 more efficiently, the imprinting process can be dualized.

That is, the stamp 10 and the resin layer 30 are thermocompressed for 30 minutes within a temperature range where the viscosity of the resin layer 30 becomes the lowest (for example, about 100 ° C.), and then in a state of being kept in a crimped state. After curing the resin layer 30 by raising the temperature to a temperature range where the resin layer 30 can be cured (for example, about 150 ° C.), a method of separating the stamp 10 and the resin layer 30 is described. It is available.

Using this method, the third embossed pattern 12 formed on the stamp 10 can be more efficiently transferred to the resin layer 30, and the separation of the pattern transferred to the resin layer 30 during or after separation. The shape can be maintained efficiently.

In addition, since the embossing method can manufacture the embossed pattern 32, which is a partition, and the substrate at the same time, there is an advantage in that the process is reduced. Can be.

In addition, the first metal plate 20 and the second metal plate 50 to be described later are composed of an electrode formed by coating a transparent electrode of ITO (Indium-Tin-Oxide) or a conductive polymer on a transparent substrate made of glass or plastic. Therefore, the charged particles can be easily attracted by applying a voltage to the electrode formed on the transparent substrate.

In addition, the first embossed pattern 32 and the second embossed pattern 52 to be described later may be made of a flexible material using polycarbonate (PC), polyethylene terephthalate (PET), polyether sulfone (PES) and polyimide film. Can be.

In addition, the first embossed pattern 32 and the second embossed pattern 52 to be described later may be made of any one material selected from the group consisting of epoxy, urethane, and polyester.

Next, as shown in FIG. 6, the first metal plate 20 on which the first relief pattern 32 is formed corresponds to the plurality of particles, and then the first metal plate 20 on which the first relief pattern 32 is formed is negative. Charge and positively charge the particles to charge the positive charged particles 40 between the first embossed pattern (32) (S40).

In addition, in the particle injection method of an electronic paper display device according to an embodiment of the present invention, the particles charged with (+) are defined as carbon black, which is black particles, and the particles charged with (-), are defined as titanium oxide, which is white particles. do. In addition, a space between the plurality of first relief patterns 32 is called a cell. That is, the positive charged particles 40 are filled in the cells between the first relief patterns 32.

The charging of the (+) charged particles 40 in the cells between the first embossed pattern 32 is shown in FIG. That is, the black charged particles 40 are filled in the cells formed between the plurality of first relief patterns 32.

Here, the (+) charged particles 40 may be made of black particles formed of carbon black or white particles formed of titanium oxide. However, in the particle injection method of the electronic paper display device according to an embodiment of the present invention, the (+) charged particles 40 will be described using black particles of carbon black as an example.

At this time, since the first embossed pattern 32 is manufactured by the imprinting method using the stamp 10, the width between the cells can be adjusted, thereby controlling the amount of charged particles charged in the cells.

In addition, since the first embossed pattern 32 is manufactured by an imprint method, each cell may be manufactured to have a constant width, and thus, the amount of charged particles charged in each cell may be uniform. In the particle injection method of the electronic paper display device according to an embodiment of the present invention, it is assumed that four (+) charged particles 40 are uniformly filled in each cell.

Next, as shown in FIG. 8, after the second metal plate 50 on which the second embossed pattern 52 is formed corresponds to the plurality of particles, the second metal plate 50 is positively charged, and the particles 60 are formed. The negative charge is charged to the (-) charged particles 60 in the cell between the second embossed pattern 52 (S50).

Here, the second embossed pattern 52 may be formed of the same material as the first embossed pattern 32 as described above.

9, the negative charged particles 60 are filled in the cells between the second embossed patterns 52. That is, the white charged particles 60 are filled in the cells formed between the plurality of second embossed patterns 52.

At this time, since the second embossed pattern 52 is manufactured by the imprinting method using the stamp 10 like the first embossed pattern 32, the width between the cells can be adjusted to adjust the amount of charged particles charged in the cells. There is an advantage.

In addition, since each cell of the second embossed pattern 52 may be manufactured to have a predetermined width by an imprint method, the amount of charged particles charged in each cell may also be uniform. In the particle injection method of the electronic paper display device according to an embodiment of the present invention, as in the case of the (+) charged particles 40, four (-) charged particles 60 are uniformly filled in each cell.

Next, as shown in FIG. 10, the first relief pattern 32 and the second relief pattern 52 are aligned to correspond (S60).

The alignment method of the first embossed pattern 32 and the second embossed pattern 52 may be aligned using a binocular lens, and alignment of ± 10 μm may be possible. Therefore, the first embossed pattern 32 and the second embossed pattern 52 can be accurately aligned.

Next, after the end portions of the first embossed pattern 32 and the second embossed pattern 52 are heat treated (S70), as shown in FIG. 11, the first embossed pattern 32 and the second embossed pattern 52. ) Is bonded (S80). That is, after the first embossed pattern 32 and the second embossed pattern 52 are aligned, they may be completely hardened and matched.

Therefore, the partition wall 70 is formed as the first embossed pattern 32 and the second embossed pattern 52 are matched with each other. As shown in FIG. 11, the cells between the partition walls 70 are uniformly filled with the positive charged particles 40 and the negative charged particles 60 at the correct ratio.

At this time, the first metal plate is an electronic paper display device, and the positive metal particles 40 and the negatively charged particles 60, which are two kinds of particles having different colors and charging characteristics, are transparent substrates having electrodes formed on one surface thereof. 20) and the second metal plate 50 is sealed.

Accordingly, the charged particles may be formed by applying a voltage to the electrodes of the upper and lower plates so that the particles collide with each other, thereby causing a charge due to the collision. Next, the electric field is applied to the particle group charged from the electrodes of the upper and lower plates having different dislocations, and the particles are moved to display an image. In this case, the electronic paper display may include one or more pixels separated from each other by the partition wall 70.

Conventionally, particles have been injected into the pixel space, which is a cell between the partition walls 70, as well as the upper part of the partition walls 70, and the relative amount of the particles injected into the cells and the relative ratio of the particle types are not uniform for each cell, resulting in unevenness on the screen. There was a problem that occurs or spots.

In the particle injection method of the electronic paper display device according to an embodiment of the present invention, a predetermined amount of the white charged particles 60 and the black charged particles 40 may be uniformly filled in each cell. It may not be filled, preventing contamination of the partition wall.

In addition, in the method of injecting an electronic paper display device according to an embodiment of the present invention, since the black charged particles 40 and the white charged particles 60 are injected at each cell in the correct absolute amount and at the correct ratio, the electronic paper display device is driven on the screen. You can improve the image quality by removing spots or spots on the screen.

In addition, in the method of injecting an electronic paper display device according to an embodiment of the present invention, the first metal plate 20 is formed by bonding the first embossed pattern 32 and the second embossed pattern 52 filled with the counter particles. An electronic paper display device having a lower substrate and a second metal plate 50 as an upper substrate can be easily manufactured.

Accordingly, since the manufacturing process for manufacturing the electronic paper display is simple, there is an effect that can reduce the cost and time required for the particle injection process.

In addition, since the barrier 70 and the substrate using the imprint method can be manufactured at the same time, the process is reduced, and since the substrate and the barrier 70 are integrated, the charged particles are moved to the adjacent barrier 70. You can prevent it.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention pertains without departing from the spirit and scope of the present invention as set forth in the claims below It will be appreciated that modifications and variations can be made.

1 is a cross-sectional view showing a spray particle coating method according to the prior art.

2 is a flowchart illustrating a particle injection method of an electronic paper display device according to an embodiment of the present invention.

3 to 5 are flowcharts illustrating a method of manufacturing a first relief pattern according to an embodiment of the present invention.

6 to 11 are flowcharts illustrating a method of injecting an electronic paper display device particle according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

10: stamp 12: third embossed pattern

20: first metal plate 30: resin layer

32: first embossed pattern 40: (+) charged particles

50: second metal plate 52: second embossed pattern

60: (-) charged particles 70: bulkhead

Claims (9)

Negatively charging a first metal plate on which a first embossed pattern is formed to fill (+) charged particles between the first embossed patterns; Positively charging a second metal plate on which a second embossed pattern is formed to fill (-) charged particles between the second embossed patterns; Arranging the first relief pattern and the second relief pattern to correspond to each other; And Particle injection method of electronic paper display device comprising the step of bonding the first relief pattern and the second relief pattern. The method of claim 1, The first embossed pattern is, Stacking a resin layer on the first metal plate; Preparing a stamp having a third relief pattern formed thereon; And Particle injection method of the electronic paper display element, characterized in that formed by the step of pressing the stamp on the resin layer. The method of claim 1, When the (+) charged particles are black particles formed of carbon black, the (-) charged particles are particles of an electronic paper display device, characterized in that the white particles formed of titanium oxide. The method of claim 1, When the (+) charged particles are white particles formed of titanium oxide, the (-) charged particles are black particles formed of carbon black. The method of claim 1, And said first metal plate and said second metal plate are formed by stacking electrodes on a substrate. The method of claim 1, The first embossed pattern and the second embossed pattern is formed of any one material selected from the group consisting of polycarbonate (PC), polyethylene terephthalate (PET), polyether sulfone (PES) and polyimide Particle injection method of paper display element. The method of claim 1, The first embossed pattern and the second embossed pattern is a particle injection method of the electronic paper display device, characterized in that made of any one material selected from the group consisting of epoxy, urethane and polyester. The method of claim 1, The aligning step, Particle injection method of an electronic paper display element, characterized in that performed using a binocular lens. The method of claim 1, After the aligning step, And heat-treating end portions of the first embossed pattern and the second embossed pattern.

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