KR20070044256A - Manufacturing process of particle for image display of electronic paper by sanding surface method, manufacturing apparatus therefor, particle for image display and electronic paper using the same - Google Patents

Abstract

The present invention relates to a method for producing an image display particle of electronic paper by a sanding external method, to a manufacturing apparatus for the same, and thus to an image display particle and an electronic paper, in particular a step of preparing a parent particle in the reactor; Injecting the external additives into the reactor prepared by the compressed air by the compressed air; In the case of the manufacturing method for the image display particles of the electronic paper by the sanding external method, including the external additives by the compressed air It can be pushed into the coating from the surface to the inside, which has the effect that the external additive does not fall well from the parent particles to maximize the fluidity of the particles.

Electronic paper, external additives, compressed air

Description

Manufacturing Process for Particles for Electronic Display by Electronic Sanding Method, Manufacturing Apparatus for It, Particles and Electronic Paper for Image Display According to Manufacturing Process of Particle For Image Display Of Electronic Paper By Sanding Surface Method, Manufacturing Apparatus Therefor, Particle For Image Display and Electronic Paper Using The Same}

1A to 1C are cross-sectional views illustrating a cell structure and driving principle of an electronic paper according to the prior art;

Figure 2 is a cross-sectional view showing a method for producing particles by the blade mixing (Blade Mixing) method according to the prior art,

3 is a cross-sectional view of a particle showing a state in which an external additive is applied to a particle surface manufactured by a blade mixing method according to the prior art,

Figure 4 is a scanning electron microscope (SEM) photograph showing a state in which the external additive is applied to the surface of the particles prepared by the blade mixing method according to the prior art,

5 is a cross-sectional view and a perspective view showing a particle manufacturing apparatus for displaying images of electronic paper by a sanding additive method according to an embodiment of the present invention,

6 is a sectional view and a perspective view showing a state in which a stirrer is further included in the manufacturing apparatus of FIG. 5;

7 is a cross-sectional view showing a particle manufacturing apparatus for displaying an image of electronic paper by sanding addition method having two injection holes according to a preferred embodiment of the present invention.

8 is a cross-sectional view showing an image display particle of an electronic paper by a sanding additive method according to an embodiment of the present invention,

FIG. 9 is a cross-sectional view illustrating a state in which a pigment, a dye, or an antistatic agent is further included in the image display particle of FIG. 8.

10 is a cross-sectional view illustrating a cell structure of electronic paper including particles for image display according to an exemplary embodiment of the present invention.

** Description of Symbols for Main Parts of Drawings **

1: parent particle 2: external additive

3: external injector 4: compressed air injector

5: compressed air 6: reactor

7: inlet 8: agitator

9: pigment or dye 10; Charge control agent

11: upper substrate 12: upper electrode

13: upper insulating layer 14: lower substrate

15: lower electrode 16: lower insulating layer

17: partition 18: particles for image display

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an image display particle of electronic paper and an electronic paper comprising the same. Particularly, a method for manufacturing an image display particle of electronic paper by a sanding external method, a manufacturing apparatus therefor, and an image display particle accordingly. And electronic paper. More specifically, the present invention relates to a method for producing an image display particle of coated electronic paper by pushing the external particles from the surface of the mother particles by the reaction between the mother particles and the external additives by compressed air.

BACKGROUND ART Conventionally, an electronic paper device using an electrophoretic method, an electrochromic method, a thermal method, a two-color particle rotation method and the like has been proposed as an image display device replacing a liquid crystal (LCD). Such an electronic paper device is considered to be a technology that can be used in the next generation of inexpensive image display devices because of the advantages of having a wider viewing angle closer to a normal printed matter, smaller power consumption, and a memory function than LCDs. Development into terminal image displays, electronic papers, and the like is expected.

In particular, in recent years, electrophoresis-type electronic paper has been proposed, which encapsulates a dispersion liquid composed of dispersed particles and a colored solution and arranges them between opposing substrates. However, in the electrophoresis method, since the particles move in the liquid, there is a problem that the response speed is slow due to the viscosity resistance of the liquid. In addition, since the high specific gravity particles such as titanium oxide are dispersed in the low specific gravity solution, they tend to settle, are difficult to maintain the stability of the dispersed state, and suffer from the problem of insufficient image repeat stability. Even in the case of microencapsulation, the cell size is set to the microcapsule level so that the above-mentioned defects are not easily seen in appearance.

In the electrophoretic method using the behavior in such a solution, two or more kinds of particles having different colors and charging characteristics are enclosed between at least one transparent substrate without using a solution in recent years, and either one of the substrates or Electronic paper has been proposed to impart an electric field to the particles from an electrode pair formed of both electrodes, and to move the particles by coulomb force to display an image. The operation mechanism of such a dry electronic paper display device is to insert a mixture of two kinds of particles having different colors and charge polarities into an electrode disc, and apply a voltage to the electrode disc to generate an electric field between the pole discs to generate a polarity. It is used as a display element by making different charged particles fly in a different direction. These are dry display devices that consist of particles and substrates and utilize particle behavior in gas, and solve problems such as sedimentation and flocculation of particles, which have been a problem in electrophoresis because no solution is used. This has the advantage of being small and fast in response.

1A to 1C are procedure cross sectional views showing an example of a cell sectional view of an image display element used in such an electronic paper, and a display driving winry thereof. In the figure, reference numeral 10 denotes a transparent substrate, 20 counter substrate, 30 display electrode (transparent electrode), 40 counter electrode, 50 negative electrode particles, 60 positive electrode particles, and 70 partition walls.

FIG. 1A shows a state in which negatively charged particles 50 and positively charged particles 60 are disposed between opposing substrates (transparent substrate 10 and opposing substrate 20). In this state, when the display electrode 30 side is applied with a voltage such that the low potential counter electrode 40 side has a high potential, as shown in FIG. 1B, the positively charged particles 60 are caused by the coulomb force to display the electrode 30. Emergency moving to the side, the negatively charged particles 50 are moved to the counter electrode 40 side. In this case, the display surface seen from the transparent substrate 10 side is seen as the color of the positively charged particles 60. Next, when the potential is switched to apply a voltage such that the display electrode 30 side has a high potential and the counter electrode 40 side has a low potential, as shown in FIG. 1C, the negatively charged particles 50 are subjected to the Coulomb force. The positive electrode 60 moves toward the display electrode 30 and the positive electrode particles 60 move toward the counter electrode 40. In this case, the display surface seen from the transparent substrate 10 side is seen as the color of the negatively charged particles 60.

1B and 1C can be repeatedly displayed by simply inverting the potential of the power supply, and the color can be reversibly changed by inverting the potential of the power supply. The color of the particles can be freely selected. For example, if the negatively charged particles 50 are made white and the positively charged particles 60 are made black, or if the negatively charged particles 50 are made black and the positively charged particles 60 are made white, the display is white. Reversible display between black is displayed. In this manner, since each particle is in a state of being attached to the electrode by ordinary force once, the display image is retained for a long time even after the power is turned off, so that memory integrity is good.

The electronic paper display device is a display device that forms an image by driving particles with an electrostatic force between electrodes. Here, two particles of different colors in each cell are charged positively by one particle and negatively charged by another by friction. As such particles, the basic resin is acrylic, silicone, urethane, etc., and is a charge control agent for increasing the amount of charge due to collision charge, and a coloring agent to make a color. The particles can be prepared according to the desired size.

However, in the particles used in the electronic paper display device, particles may aggregate with each other depending on the state of charge of each particle or by the influence of the surrounding environment. When the oppositely charged particles agglomerate with each other, a problem occurs that the external voltage does not move anymore, and in order to prevent the agglomeration of the charged particles, as shown in FIG. It is coated and used by the blade mixing method.

Figure 2 is a cross-sectional view showing a method for producing particles by the blade mixing (Blade Mixing) method according to the prior art. To this end, as shown, the particles (100, 60) and the external additives 80 are injected together in the reactor (90) in which the blade (100) is installed, and the blade (100) by the motor (110) Rotating so that the external additive (80) is attached to the particles (50, 60). The coating of the external additive 80 to the particles 50 and 60 is to improve the fluidity of the particles 50 and 60, and the amount of the external additive 80 to be added is about 10% of the particles 50 and 60. , The external additive 80 is mixed with the particles 50 and 60 in the reactor 90, and then mixed at about 1000 to 3000 rpm at about 1 to 10 minutes.

Electronic paper particles coated with an external additive in this manner are shown in FIGS. 3 and 4. 3 is a cross-sectional view illustrating particles in which an external additive 80 is applied to surfaces of particles 50 and 60 manufactured by a blade mixing method according to the related art. As shown, the outermost of the particles 50, 60 is simply physically coated with an external additive 80 such as a resin, silicone resin or coupling agent. As described above, the conventional blade mixing method has problems such as entanglement of particles due to frictional heat between the blade and the particles due to high speed driving, uneven application of external additives, or melting of the particles on the blade portion. Therefore, it is a problem to secure the uniformity after external addition, and in such a case, when it is injected into the device of the electronic paper, there is a problem that the contrast of the cell varies for each pixel.

In addition, as shown in the scanning electron microscope (SEM) photograph of FIG. 4, when the external additive is present in the form of sparsely aggregated on the surface of the particle, the external additive may easily fall off from the parent particle. As such, when the external additive is easily dropped, the charged particles may not respond sufficiently by the same applied voltage, and the charging characteristics may be easily changed, thereby leading to a serious problem of poor image quality. In addition, as a whole, the unity of image quality is reduced, resulting in shortening of product life.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to provide particles for displaying images of electronic paper coated with the external additives being pushed inwards from the surface of the mother particles by reacting the mother particles with the external additives by compressed air. It is an object of the present invention to provide an electronic paper capable of maximizing the fluidity of particles because the external additive does not fall off from the mother particles by the present invention.

In addition, by using the method for producing the particles by the sanding additive method according to the present invention, the external additive can be pushed into the coating from the surface of the mother particle by compressed air, so that the external additive does not fall off from the mother particle well. To provide electronic paper particles. In addition, it is to prevent the entanglement of the particles by eliminating the generation of frictional heat generated by the physical impact of the external additives when the external additives. According to the present invention, the external additives are collided with the compressed air together with the compressed air by separating and externally mixing the particles and the external additives in advance, and then externally adding the external additives from the particle surface to the inside more effectively. For coating.

In addition, by coating the external additives to the inside of the particles slightly deep coating to increase the fluidity of the particles, and to eliminate the disadvantage that the external additives fall off when driving after the injection into the device. In addition, it is an object of the present invention to produce an electronic paper that can significantly increase the fluidity of the particles by the external additive, while uniformly coating the surface of the particles with a nano-sized external additive through the present invention to uniformly charge the particles. .

According to an embodiment of the present invention, there is provided a method for preparing particles for displaying images of electronic paper by a sanding addition method, comprising: preparing a mother particle in a reactor; Injecting external additives into the reactor in which the mother particles are prepared by compressed air.

Here, the reactor may be characterized in that it comprises a stirrer capable of stirring the inside of the reactor, after the step of injecting the external additive, the external additive injected by the compressed air is pushed in from the surface of the mother particle It is also possible to further include; coating the parent particles.

Another preferred embodiment of the method for producing particles for displaying images of electronic paper by the sanding addition method according to the present invention comprises the steps of preparing a reactor; Injecting external additives and parent particles into the reactor by compressed air.

Here, the external additives and the parent particles are preferably injected separately into separate inlets in the reactor, it is more preferable that the separate inlets in the reactor are located opposite each other. In addition, the reactor includes a stirrer capable of stirring the inside of the reactor, it is also possible to produce an image display particle of the electronic paper by the sanding external method. In addition, after the step of injecting the external additive, the external additive injected by the compressed air is pushed in from the surface of the mother particle to be coated on the mother particle; may further include.

Particle manufacturing apparatus for image display of electronic paper by a sanding additive method for achieving another object of the present invention comprises a reactor capable of reacting the parent particles and the external additive coated on the mother particles; And an inlet for injecting at least one of the parent particles and the external additive into the reactor by compressed air.

Here, the inlet for injecting at least one of the parent particles and the external additive by the compressed air is preferably an inlet for injecting the external additive, further comprising a stirrer capable of stirring the inside of the reactor An apparatus for producing particles for displaying images of electronic paper by a sanding additive method is also possible. In addition, the compressed air injection device for blowing the compressed air into the inlet may be further included.

Particles for image display of electronic paper by the sanding additive method for achieving the another object of the present invention is characterized in that the external additives are pushed into the coating from the surface of the mother particles by coating the parent particles and the external additives by compressed air. It is done. Such particles may be particles for image display of electronic paper by sand addition method manufactured by the method for producing particles for image display of electronic paper by sand addition method as described above.

Electronic paper including particles for image display by a sanding additive method for achieving the another object of the present invention is the mother particles and the external additives are reacted by the compressed air, the external additives are pushed into the interior from the surface of the mother particles coated It is characterized by including particles. Such particles may be electronic paper including particles for image display of electronic paper by sand addition method manufactured by the method for producing particles for image display of electronic paper by sand addition method as described above.

Here, it is also possible to further include an opposing substrate, at least one of which is transparent, and an electrode for imparting an electric field between the substrates. The barrier rib may further include a partition wall that divides the pixel space between the electrodes.

In the image display particles, the parent particles are PMMA (poly methyl methcrylate), polyethylene terephthalate (PETE), polystyrene (PS), polyethylene, polypropylene, phenol resin, Du Pont Elvax resin ( Ethylene-vinyl acetate copolymers), polyesters, polyacrylates, polymethacrylates, ethylene acrylic acid or methacrylic acid copolymers (Nucrel Resins-Dupont, Primacor Resins-Dow Chemical), acrylic acid copolymers and trimers (Elvacite Resins) , DuPont) is preferably selected from the group consisting of at least one, the particles for the image display may further include a pigment or dye stained, it is also possible to further include a charge control agent for controlling the amount of charge.

In addition, the external additive externally attached to the parent particles of the electronic paper according to the present invention is for improving the fluidity of the particles, and includes an image display particle by the sanding external addition method, characterized in that it is made of ceramic powder or natural or synthetic wax. can also be e-paper, and wherein the ceramic powder is silica (SiO _2), barium titanate (BaTiO _3), strontium titanate (SrTiO _3), calcium titanate (CaTiO _3), lead titanate (PbTiO ₃ ), titanium dioxide (TiO ₂ ), tin dioxide (SnO ₂ ), calcium oxide (CaO), magnesium oxide (MgO), aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), gamma iron oxide, magnesium Silicate (MgSiO ₃ ), magnetite (Fe ₃ O ₄ ), zirconia (ZrO ₂ ), boron oxide (B ₂ O ₃ ), silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), nickel ferrite, Zinc Ferrite, Nickel Zinc Ferrite and Barium Ferra Bit (BaFe ₂ O ₄₎ is preferably at least one or more selected from the group consisting of the natural or synthetic wax S- wax, PE wax, ethylene-acrylic acid waxes, ethylene-vinyl acetate, carboxylic acid is partially bonded to the distal At least one of the group consisting of a montan-based natural wax, a polyethylene-based synthetic wax, a polypropylene-based synthetic wax, a polymer wax, and a synthetic wax having a basic functional group partially bonded to an amide or an amine at the end thereof. More preferably selected.

In addition, the image display particle according to the present invention is preferably an electronic paper containing the image display particles by sand addition method, characterized in that the chargeable or charged dry particles.

Hereinafter, one preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

5 is a cross-sectional view and a perspective view showing a particle manufacturing apparatus for displaying images of electronic paper by a sanding additive method according to an embodiment of the present invention. As shown in FIG. 5, in the method for preparing particles for displaying images of electronic paper by the sanding addition method according to the present invention, a mother particle 1 is prepared inside the reactor 6 and the mother particle 1 is prepared with a reactor ( 6) injecting the external additive (2) by the compressed air (5) inside.

Thus, in the present invention, in externalizing the external additive 2 to the mother particle 1, the mother particle 1 is first prepared by the reactor 6 in which the mother particle 1 is prepared and then by the compressed air 5 into the reactor 6. Inject the additive (2). Through this, unlike the conventional blade mixing method, the blade, particles, and external additives during external addition do not generate frictional heat generated by physical collision. That is, in the related art, the mother particle and the external additive are put together in the reactor, and then the blade is rotated by a motor so that the external additive is bound to the mother particle by the rotation, but according to the present invention, the reactor in which the mother particle 1 is prepared first. When the external additive 2 is injected into the compressed air 5 through the compressed air 5, the external additive 2 can be coated on the mother particles 1 without frictional heat. Therefore, in the case of the present invention as described above, entanglement between particles due to frictional heat does not occur.

According to another preferred embodiment of the present invention, after the step of injecting the external additive, the external additive injected by the compressed air is pushed into the coating from the surface of the parent particle. According to the present invention, the method for producing the particles by the sanding external addition method does not generate frictional heat generated by physically colliding when the external additives are externally attached, and thus no entanglement of the particles is present. According to the present invention, the external additives may collide with the particles together with the compressed air in such a manner that the particles and the external additives are not mixed together and then externally added, which is a conventional method. There is an advantage. In other words, the external additive can be pushed slightly deep into the particle.

This increases the fluidity of the particles, and also eliminates the disadvantage that the external additives fall off when driven after the injection into the device. In addition, in the present invention, since the nano-sized external additive is uniformly coated on the surface of the particles, while the amount of charge between particles is constant, the fluidity of the particles by the external additives can be significantly increased.

In addition, the present invention is characterized in that the parent particles and the external additives react in the reactor, the external additives are injected into the reactor through the inlet by compressed air, but the parent particles are prepared in the reactor in advance Yet another preferred embodiment of the present invention may be characterized in that the reactor 6 is attached to the reactor 6 to stir the inside of the reactor 6. 6 is a cross-sectional view and a perspective view showing a state in which a stirrer is further included in the apparatus of FIG. 5.

Here, when the stirrer 8 is attached to the reactor 6 as shown, even if the mother particle 1 is prepared in advance inside the reactor 6, the mother particle 1 inside the reactor 6 is provided. The entire external additive (2) can be coated evenly. That is, if there is no stirrer 8 in the reactor 6, the parent particles 1 at the top inside the reactor 6 have many opportunities for contact with the external additive 2, but the reactor 6 The mother particle 1 at the bottom of the inner side does not have many opportunities to contact the external additive 2. Of course, it is also possible to blow up the parent particles 1 inside the reactor 6 by the compressed air 5, but the reactor 6 is deep and evenly distributed by the compressed air. If not possible, a reactor 6 in which the stirrer 8 is attached according to the invention is more preferred.

Another preferred embodiment of the method for producing particles for displaying images of electronic paper by the sanding addition method according to the present invention comprises the steps of preparing a reactor; Injecting external additives and parent particles into the reactor by compressed air. What is different from the above-described manufacturing method is that the parent particles as well as the external additives are injected into the reactor by compressed air.

A feature of the present invention is that in order to externally attach the external additives to the mother particles, the external additives are pressed into the mother particles by compressed air without using a conventional mixing method by rotating the blades. If the particles are to be reacted, another preferred embodiment of the present invention is capable of injecting not only external additives but also parent particles into the reactor by compressed air. That is, it is also possible to provide the mother particles in advance in the reactor, but the external additive and the mother particles are injected together into the reactor by adjusting the compressed air without preparing the mother particles in advance in the reactor. Even if the external additives and the parent particles are injected by the compressed air, the external additives may be coated on the surface of the mother particles, and by blowing the compressed air, the external additives may be pushed in from the surface of the mother particles.

As such, the method of injecting the external additives and the mother particles by the compressed air into the reactor has a form in which the external additives 2 and the mother particles are separately injected through separate injection holes in the reactor as shown in FIG. 7. desirable. 7 is a cross-sectional view showing a particle manufacturing apparatus for image display of electronic paper by sanding external method having two injection holes according to an embodiment of the present invention. Specifically, as shown in which the external additive is injected, the external additive 2 and the parent particle 1 according to the present invention is injected into the reactor 6 through a separate inlet, thereby the external additive (2) and The frequency of collision of the parent particles 1 can be increased, and the external additive 2 can be more easily coated on the mother particles 1.

As described above, a form in which the external additive 2 and the parent particle 1 are injected together through one injection hole may also be included, but in order to coat the external additive 2 to the mother particle 1, the reactor 6 It is preferable to be divided into separate injection inlets in each of the), and the separate inlets in the reactor (6) is more preferably located opposite each other of the reactor (6) as shown in FIG. By injecting the external additive 2 and the mother particle 1 in opposite directions, the collision frequency of the external additive 2 and the mother particle 1 is further maximized, and the external additive 2 is removed by the frontal collision. It can be coated deeper into the interior from the surface of the parent particle (1).

In the present invention, the reactor may be attached to a stirrer capable of stirring the inside of the reactor, and after the step of injecting the external additive, the external additive injected by the compressed air is moved from the surface of the mother particle to the inside. As described above it may further comprise the step of being pushed in and coated.

Another object of the present invention is to provide an apparatus for producing particles for displaying images of electronic paper according to the above-described sanding addition method, for image display of electronic paper by sanding addition method for achieving the above object. Particle production apparatus includes a reactor capable of reacting the parent particles and the external additive coated on the mother particles; And an inlet for injecting at least one of the parent particles and the external additive into the reactor by compressed air.

Preferred embodiments of such a particle production apparatus are as shown in Figs. That is, as shown in FIG. 5, there must be a reactor 6 capable of reacting the parent particle 1 and the external additive 2, wherein the mother particle 1 or the external additive 2 is compressed air ( There should be an injection opening 7 which can be injected by 5). In this case, the inlet 7 may be included in the reactor 6 or may be attached to the reactor 6. In addition, the injection hole 7 may be connected to the external additive injector 3 for injecting the external additive 2 and the compressed air injector 4 for injecting the compressed air 5 to form one injection hole 7. And, as shown in Figure 7 may be connected to the inside of the reactor through a separate inlet (7).

The compressed air 5 may be injected into the external additive 2 or the mother particle 1, and both the external additive 2 and the mother particle 1 may be injected into the reactor 6 by the compressed air 5. It is also possible to inject inside. Preferably, in view of the external additive 2 being externalized on the surface of the parent particle 1, it is suitable that the external additive 2 is injected into the reactor 6 by the compressed air 5. That is, the injection hole for injecting at least one of the parent particles 1 and the external additive 2 by the compressed air 5 is preferably an injection hole 7 through which the external additive 2 can be injected.

In addition, the apparatus for producing particles for displaying images of electronic paper by the sanding additive method according to the present invention further includes a stirrer 8 capable of stirring the inside of the reactor 6 as shown in FIG. 6. It is also possible to. The stirrer 8 may be formed integrally with the reactor 6, or may be provided separately from the reactor 6. As described above, the external additives 2 and the mother particles 1 are more easily reacted by mixing the external additives 2 and the mother particles 1, in particular, by mixing the mother particles 1 evenly.

In addition, although the compressed air injector 4 shown in FIGS. 5 to 7 is for injecting the compressed air 5, the compressed air injector 4 may be a compressed air injector capable of blowing compressed air. The present invention may further include a compressed air injector (not shown) capable of blowing compressed air 5 separately from the compressed air injector 4.

Another preferred embodiment for achieving another object of the present invention is an image display particle of the electronic paper by the sanding addition method and an electronic paper comprising the same. Specifically, the particles for image display are characterized in that the mother particles and the external additives are reacted by compressed air, so that the external additives are pushed in from the surface of the mother particles and coated. In addition, the particles may be manufactured by the method for producing particles for displaying images of electronic paper by the sanding addition method as described above.

Fig. 8 is a cross-sectional view showing particles for displaying images of electronic paper by sand addition method according to a preferred embodiment of the present invention. As shown, the particle for image display according to the present invention is characterized in that the external additive 2 is injected by compressed air and pushed into the interior from the surface of the mother particle 1 to be coated. Since the conventional external additives are mixed with the mother particles by mixing by the blades, the external additives have a form in which the external additives are sparsely distributed on the surface of the mother particles. However, when the particles are manufactured by the sanding external addition method according to the present invention, the mother particles (1) Since the external additive (2) is not mixed beforehand and then externally added as before, the external additive (2) is separated from the external additive (2) and the parent particles (1) separately and externally added. Impingement on the particles 1 can be more effectively coated on the inside of the parent particle (1) surface. That is, the external additive 2 can be pushed a little deeper into the mother particle 1. This increases the fluidity of the particles, and also eliminates the disadvantage that the external additive 2 falls off during driving after the injection into the device. In addition, in the present invention, since the nano-size external additive 2 is uniformly coated on the surface of the particles, the amount of charge between particles is constant, and the flowability of the particles by the external additive 2 is remarkably increased.

As described above, the present invention relates to an image display particle of electronic paper by sand addition method, wherein the parent particle used in the present invention is any component capable of being charged or obtaining a charge, and the surface of such mother particle. It is coated with a charged external additive, which may further include a dyed pigment or dye 9, which may be colored as shown in FIG. 9, or a charge control agent 10 capable of controlling the charge of the particles. It is characterized by being. Hereinafter, after describing the mother particle (1) and the external additive (2) constituting the charged particles of the collision charging type electronic paper according to the present invention, the pigment, dye (9) or charge control agent (10) described above. Let's take a closer look.

First, the mother particle 1 for image display including the external additive 2 inside as the mother particle 1 used in the present invention will be described. There is much flexibility in the selection of particles for use in electrophoretic electronic paper. The parent particles used for the purposes of the present invention are preferably any component that is charged or capable of obtaining a charge (ie, having or obtaining electrophoretic mobility). These parent particles may be pure pigments, dyed (laked) pigments or pigment / polymer composites or any other component that can be charged or obtain a charge. Typical considerations for electrophoretic charged particles are their optical, electrical and surface chemistries, and the parent particles according to the invention can be organic or inorganic compounds and can absorb or scatter light. have. The parent particles for use in the present invention may further include scattering pigments, absorbing pigments and luminescent particles. The parent particle may be retroreflective such as a corner cube, or may be electroluminescent, such as zinc sulfide particles that emit light when excited by an AC field, or may be photoluminescent.

Specifically, the mother particles 1 may be titanium dioxide, zinc oxide, zinc emulsion, white lead, sulfur lead, cadmium sulfide, graphite, carbon black, and the like, and polymers useful for such mother particles are not limited to PMMA. (poly methyl methcrylate), polyethylene terephthalate (PETE), polystyrene (PS), polyethylene, polypropylene, phenolic resin, Du Pont Elvax resin (ethylene-vinyl acetate copolymer), polyester, polyacrylic Latex, polymethacrylate, ethylene acrylic acid or methacrylic acid copolymers (Nucrel Resins-Dupont, Primacor Resins-Dow Chemical) acrylic acid copolymers and trimers (Elvacite Resins, DuPont). Further, as these copolymers, materials useful for high shear melting homopolymers and / or pigment phase separation include, but are not limited to, polyethylene, polypropylene, polymethyl methacrylate, polyisobutyl methacrylate, polystyrene, Polybutadiene, polyisoprene, polyisobutylene, polylauryl methacrylate, polystearyl methacrylate, polyisobornyl methacrylate, poly-t-butyl methacrylate, polyethyl methacrylate, polymethyl Acrylate, polyethyl acrylate, polyacrylonitrile and copolymers of two or more such materials. The size of the mother particle 1 is most preferably about 0.2 ~ 2.0㎛.

And, the external additive (2) is deeply coated on the mother particle (1) according to the present invention by a sanding external method. The external additive (2) constituting the image display particles of the electronic paper according to the present invention is to increase the fluidity of the particles or to prevent them from adhering to the capsule wall, and is typically used as a suspension fluid in electrophoretic displays. Non-aqueous surfactants can be used for resistivity liquids. Each component can be constructed from materials that span a wide range of molecular weights (low molecular weight, oligomeric, or polymerizable), and can be pure or a mixture. In all such industries, charged species may be added to non-aqueous media to increase electrophoretic mobility or increase electrostatic stabilization. Although not limited thereto, glycol ethers, acetylene glycols, alkanolamides, sorbitol derivatives, alkyl amines, quaternary amines, imidazolines, dialkyl oxides and sulfosuccinates may be used, preferably nano size It is suitable to use silica.

In the present invention, such an external additive (2) not only plays a role of particle stabilization for improving the fluidity of the particles, in particular, as a charged external additive, by changing the charge amount size and polarity of the particles as in the conventional charge control agent You can also adjust the amount of charge. Specifically, the external additive 2 is for improving the fluidity of the particles, and may be ceramic powder or natural or synthetic wax.

More specifically, the serak mix powder is silica (SiO _2), barium titanate (BaTiO _3), strontium titanate (SrTiO _3), calcium titanate (CaTiO _3), lead titanate (PbTiO ₃₎ , Titanium dioxide (TiO ₂ ), tin dioxide (SnO ₂ ), calcium oxide (CaO), magnesium oxide (MgO), aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), gamma iron oxide, magnesium silicate ( MgSiO ₃ ), magnetite (Fe ₃ O ₄ ), zirconia (ZrO ₂ ), boron oxide (B ₂ O ₃ ), silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), nickel ferrite, zinc ferrite, nickel At least one selected from the group consisting of zinc ferrite and barium ferrite (BaFe ₂ O ₄ ), the natural or synthetic wax is S-wax, PE wax, ethylene-acrylic acid wax, ethylene-vinylacetate, at the end Montan series with partially conjugated carboxylic acids Natural waxes, will have at least one from the group consisting of synthetic waxes with a synthetic wax, poly synthetic wax, a polymer wax, and ends of the propylene series of polyethylene-based amide or amine groups in part of the basic functions can be selected with bonding.

Next, the image display particles comprising the dyed pigments or dyes 9 may generally be pigments, polymers, laked pigments or some combination thereof. Black pigments include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, and the like. For white expression, titanium oxide (TiO ₂ ) may be representatively used. In addition, there are yellow pigments, orange pigments, red pigments, purple pigments, green pigments and the like, and various dyes such as alkaline, acidic, disperse and direct dyes such as nigrosine, methylene blue and rose bengal. ， Quinoline yellow, ultramarine blue and the like can also be used. These pigments and dyes may be used alone or in combination of a plurality of.

In addition, a charge control agent 10 may be additionally added to the image display particles according to the present invention, which may control the charge amount of the particles by changing the charge amount and polarity of the particles. The charge control agent 10 is not particularly limited, but examples of the negative charge control agent include metal salicylic acid complexes, metal-containing azo dyes, oil-soluble dyes containing metal ions or metal atoms, and quaternary ammonium salt compounds. , A calixarene compound, a boron-containing compound (boron benzyl nitrate complex), a nitroimidazole derivative, and the like. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and the like. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide, ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives thereof, salts, resins containing various organic pigments, fluorine, chlorine, nitrogen and the like can also be used as charge control agents. .

Finally, another preferred embodiment for achieving another object of the present invention is an electronic paper containing particles for image display by the sanding addition method as described above. The electronic paper is characterized in that the parent additive and the external additive react with compressed air, so that the external additive is pushed in from the surface of the parent particle and includes particles for image display by a sanding additive method coated thereon. Is preferably produced by the method for producing particles for image display of electronic paper by the sanding addition method as described above.

The electronic paper containing the image display particles by the sanding addition method is contained in a space between at least one of the particles for image display by the sanding addition method facing the transparent substrate at predetermined intervals, and between the substrates. It is also possible to further include an electrode for imparting an electric field to the. In addition, it may be characterized by further comprising a control means for changing the distribution state of the charged particles by applying a control voltage to the electrode.

10 is a cross-sectional view illustrating a cell structure of an electronic paper including particles for image display according to an exemplary embodiment of the present invention. That is, the electronic paper according to the present invention has opposing upper and lower substrates 11 and 14, upper and lower electrodes 12 and 15 positioned between these substrates, and the above-described images according to the present invention, as shown in FIG. It consists of the display particle 18 and the partition 17 provided as needed.

In the electronic paper according to the present invention, the upper and lower substrates 11 and 14 are transparent substrates capable of confirming the color of the image display particles 18 from the outside of the electronic paper, and have a high transmittance of visible light and good heat resistance. Is suitable. Examples of the substrate material include polymer sheets such as polyethylene terephthalate, polyether sulfone, polyethylene and polycarbonate, and inorganic sheets such as glass and quartz.

In addition, upper and lower electrodes 12 and 15 may be formed on the substrate. If no electrode is formed on the substrate, an electrostatic latent image is formed on the outer surface of the substrate, and the colored fractionation body charged with a predetermined characteristic with an electric field generated by the electrostatic latent image is attracted to or repelled by the electrostatic latent image. The correspondingly arranged sorting bodies can be seen from the outside of the display device through the transparent substrate. In the case of providing the electrode on the substrate, electrostatic latent image is applied by attracting or repulsing a color classification body charged with a predetermined characteristic by an electric field generated at each electrode position on the substrate by an external voltage input to the electrode portion. Can be viewed from the outside of the display device through a transparent substrate. The electrode at this time is formed of a transparent and patternable conductive material. Examples thereof include metals such as indium oxide and aluminum, conductive polymers such as polyaniline, polypyrrole and polythiophene, and vacuum deposition and coating. The formation method of can be illustrated.

In addition, in the electronic paper according to the present invention, in order to prevent extra movement in the substrate parallel direction of the particles for image display, it is necessary to form a partition wall 17 connecting the opposing substrates and configure the display portion by a plurality of display cells. desirable. The shape of a partition is appropriately optimally set by the size of the sorting body regarding display, and is not limited uniformly.

Subsequently, a lower insulating layer 16 or an upper insulating layer 13 may be further formed on the lower electrode or the upper electrode according to the present invention. That is, the electronic paper including the image display particles according to the sanding additive method according to the present invention may further include a lower insulating layer and an upper insulating layer inscribed to the lower electrode and the upper electrode, respectively. The lower insulating layer or the upper insulating layer may be formed to prevent electrophoretic particles from adhering to the electrode and being discharged. Although the lower insulating layer or the upper insulating layer applied on the lower electrode or the upper electrode is omitted, there is no problem in driving. However, when the charged particles are in close contact with the electrode and the electron movement occurs, the memory effect is reduced and the image is applied without applying new power. It may be difficult to preserve for a long time, so it is preferable to apply.

In addition, the image display particles according to the present invention is preferably an electronic paper containing the image display particles by sand addition method, characterized in that the chargeable or charged dry particles. In the electronic paper according to the present invention, the particles are used for image representation, and any particles for image display used for image representation in the art may be used. Among these, dry particles may be preferably selected. Electrophoretic particles having different colors and charging characteristics may be selected. In order to display black and white, it is preferable to use carbon black as black particles and titanium oxide as white particles. The charged particles may be injected, or may be applied while charging by using a corona discharge at the time of particle application. The present invention can also be applied to wet electronic paper using a microcapsule without a partition wall. Preferably, after injecting uncharged particles, a voltage is applied to the upper and lower electrodes, and the particles collide with each other to collide with each other. It is suitable for an electronic paper display device having a dry-type collision-charged electrophoretic particle that forms an electrophoretic particle by applying a charge thereof.

In the above description, it should be understood that those skilled in the present invention can only make modifications and changes to the present invention without changing the gist of the present invention as merely illustrative of a preferred embodiment of the present invention.

As described above, the present invention is to solve the problem that the external additive is easily present in the form of sloppy agglomeration on the surface of the particle when the particle is prepared by the conventional blade mixing method, and the external additive easily falls from the particle. Preparing a parent particle therein; Injecting the external additives into the reactor prepared by the compressed air by the compressed air; In the case of the manufacturing method for the image display particles of the electronic paper by the sanding external method, including the external additives by the compressed air It can be coated by pushing from the surface to the inside, which has the effect that the external additive does not fall well from the parent particles.

In addition, according to the present invention, the method for producing the particles by the sanding external addition method does not generate frictional heat generated by physically colliding when the external additives are externally entangled so that entanglement of the particles does not exist. According to the present invention, the external additives may collide with the particles together with the compressed air in such a manner that the particles and the external additives are not mixed together and then externally added, which is a conventional method. There is an advantage. In other words, the external additive can be pushed slightly deep into the particle. Therefore, it is possible to increase the fluidity of the particles, and also eliminate the disadvantage that the external additives fall off when driving after the injection into the device. In addition, in the present invention, since the nano-sized external additive is uniformly coated on the surface of the particles, while the amount of charge between particles is constant, the fluidity of the particles by the external additives can be significantly increased.

Claims (25)

Preparing a parent particle inside the reactor; And a step of injecting an external additive into the reactor into which the mother particles are prepared by compressed air. The method of manufacturing particles for displaying images of electronic paper by a sanding external method. The method of claim 1, wherein the reactor includes a stirrer capable of stirring the inside of the reactor. According to claim 1, After the step of injecting the external additive, And the external additive injected by the compressed air is pushed into the mother particle from the surface of the mother particle and coated on the mother particle. Preparing a reactor; And injecting external additives and parent particles by compressed air into the reactor. 5. The method of claim 4, wherein the external additives and the parent particles are separately injected into separate injection holes in the reactor. 6. The method of claim 5, wherein the separate injection holes in the reactor are located opposite to each other. 5. The method of claim 4, wherein the reactor includes an agitator capable of stirring the inside of the reactor. According to claim 4, After the step of injecting the external additive, And the external additive injected by the compressed air is pushed into the mother particle from the surface of the mother particle and coated on the mother particle. A reactor capable of reacting the mother particles with the external additive coated on the mother particles; And And an injection hole for injecting at least one of the mother particles and the external additive into the reactor by compressed air. The image display of electronic paper by sand addition method according to claim 8, wherein the injection hole into which at least one of the parent particles and the external additive can be injected by compressed air is an injection hole through which the external additive can be injected. Dragon particle manufacturing apparatus. 10. The apparatus of claim 9, further comprising: a stirrer capable of stirring the inside of the reactor. 10. The apparatus of claim 9, further comprising a compressed air injection device capable of blowing compressed air into the injection hole. Particles for image display of electronic paper by a sanding external coating method, wherein the external particles are pushed in from the surface of the mother particle by the reaction between the mother particles and the external additives by compressed air. Particles for image display of electronic paper by the sanding additive method produced by the manufacturing method according to any one of claims 1 to 8. An electronic paper comprising particles for image display by a sanding external coating method in which the external particles are pushed inward from the surface of the mother particles by the reaction between the mother particles and the external additives by compressed air. An electronic paper comprising particles for image display by a sanding additive method produced by the manufacturing method according to any one of claims 1 to 8. 16. The electronic paper of claim 15, further comprising a substrate facing at least one of which is transparent, and an electrode for imparting an electric field between the substrates. 18. The electronic paper of claim 17, further comprising: partition walls for dividing pixel spaces between the electrodes. The method of claim 15, wherein the parent particles are poly methyl methcrylate (PMMA), polyethylene terephthalate (PETE), polystyrene (PS), polyethylene, polypropylene, phenol resin, Du Pont Elvax resin (ethylene- Vinyl acetate copolymers), polyesters, polyacrylates, polymethacrylates, ethylene acrylic acid or methacrylic acid copolymers (Nucrel Resins-Dupont, Primacor Resins-Dow Chemical), acrylic acid copolymers and trimers (Elvacite Resins, DuPont) Electronic paper comprising particles for image display by a sanding additive method, characterized in that at least one selected from the group consisting of). 16. The electronic paper of claim 15, wherein the particles for image display further comprise dyed pigments or dyes. 16. The electronic paper according to claim 15, wherein the image display particles further include a charge control agent for controlling the amount of charge. The electronic paper according to claim 15, wherein the external additive is for improving the fluidity of the particles, and includes an image display particle by sand addition method, comprising ceramic powder or natural or synthetic wax. The method of claim 22 wherein the ceramic powder is silica (SiO _2), barium titanate (BaTiO _3), strontium titanate (SrTiO _3), calcium titanate (CaTiO _3), lead titanate (PbTiO ₃ ), Titanium dioxide (TiO ₂ ), tin dioxide (SnO ₂ ), calcium oxide (CaO), magnesium oxide (MgO), aluminum oxide (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), gamma iron oxide, magnesium Silicate (MgSiO ₃ ), Magnetite (Fe ₃ O ₄ ), Zirconia (ZrO ₂ ), Boron Oxide (B ₂ O ₃ ), Silicon Carbide (SiC), Silicon Nitride (Si ₃ N ₄ ), Nickel Ferrite, Zinc Ferrite , Nickel zinc ferrite and barium ferrite (BaFe ₂ O ₄ ) Electronic paper comprising a particle for image display by the sanding additive method, characterized in that at least one selected from the group consisting of. The synthetic wax of claim 22, wherein the natural or synthetic wax is S-wax, PE wax, ethylene-acrylic acid wax, ethylene-vinylacetate, montan-based natural wax partially fused with carboxylic acid at the end, and synthetic polyethylene. Particles for image display by sand addition method, characterized in that at least one selected from the group consisting of a wax, a polypropylene-based synthetic wax, a polymer wax and a synthetic wax having a basic functional group partially bonded to an amide or amine at the end. Electronic paper comprising a. 16. The electronic paper of claim 15, wherein the image display particles are chargeable or charged dry particles.

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