KR101015614B1 - Electronic paper display apparatus by using teos fluent particle and manufacturing process thereof - Google Patents

Abstract

The present invention relates to an electronic paper display device using the TEOS fluid particles, the electronic paper display device using the TEOS fluid particles according to the present invention, which forms a cell between the upper substrate and the lower substrate disposed to face at a predetermined interval An electronic paper display device in which a partition wall and charged particles are filled in the cell, comprising: an electrode formed in contact with at least one of the upper substrate and the lower substrate; A first partition wall including at least one hole and positioned between the upper substrate and the lower substrate and disposed to face the upper substrate and the lower substrate, respectively; A second partition wall that divides pixels between the upper substrate and the lower substrate and connects the upper substrate and the lower substrate; Charged particles filled in a cell formed by the first and second partition walls; The charged particles are based on a solvent and 100 parts by weight of a solvent, 5 to 20 parts by weight of monomer, 0.1 to 3 parts by weight of polymerization initiator, 0.5 to 15 parts by weight of dispersion stabilizer, 0.5 to 2 parts by weight of tetraolmalbutyl titanate, and tetraethylortho. Silicate (Tetraethyl Ortho silicate) is characterized in that it comprises 0.7 to 5 parts by weight.

According to the present invention, it is possible to prevent collision between particles of different charging characteristics and aggregation of particles due to electrostatic attraction by using single particles, thereby increasing the durability of the device, thereby forming a specially shaped partition wall. As a result, the aperture ratio and contrast ratio of the display device can be improved while the single particles are used, and the reaction speed can also be improved.

Single particle, electronic paper, partition, projection, tetraethylorthosilicate, silane treatment

Description

Electronic paper display device using TEOS fluid particles and its manufacturing method {ELECTRONIC PAPER DISPLAY APPARATUS BY USING TEOS FLUENT PARTICLE AND MANUFACTURING PROCESS THEREOF}

The present invention relates to an electronic paper display device using TEOS fluid particles and a method for manufacturing the same. More particularly, tetraethyl ortho silicate is used to increase the conversion to silica, and titanium dioxide (TiO _{2) in the} polymer. ) By producing a flowable particle combined with silica (SiO ₂ ) and the like by dispersion polymerization to improve reflectance, produce excellent flowable particles with low initial driving voltage, use single particles, and diversify the shape of the partition wall. TEOS fluidity that prevents particle aggregation due to electrostatic attraction, increases durability of electronic paper display devices, improves aperture ratio and contrast of display elements, and easily forms partitions in various forms by using an imprint method. The present invention relates to an electronic paper display device using particles and a method of manufacturing the same.

BACKGROUND ART Conventionally, as an image display device replacing a liquid crystal display device (LCD), an electronic paper manufactured by an electrophoretic method, an electrochromic method, a thermal method, and a two-color particle rotation method has been proposed. Compared to LCD, the electronic paper has a wider viewing angle, which is closer to a normal printed matter, has a smaller power consumption, has a memory function, and can be used for an inexpensive image display device. It is becoming.

This electronic paper technology uses the rapid movement of microparticles by an electric field to electrostatically move charged particles floating in a certain space to display colors, and after moving at any pole due to the memory effect. Even if the voltage is removed, the image does not disappear because there is no change in the position of the particles, so that the effect is as if printed on paper. In other words, it does not emit light by itself, but the visual fatigue is very low, so it is possible to enjoy a comfortable viewing like a real book, and the panel's flexibility is high enough to bend and the thickness can be formed very thin. There is great expectation as a display device technology. In addition, as mentioned, power consumption is extremely low since the displayed image is maintained for a long time unless the panel is reset, thereby making it excellent as a portable display device. In particular, low prices due to simple processes and low cost materials are expected to contribute to the popularization of electronic paper.

In general, the electronic paper technique used is an electrophoretic method in which a dispersion liquid consisting of dispersed particles and a colored solution is microencapsulated and disposed between opposing substrates, and particles are moved in the dispersion liquid, and at least without a solution. Between two transparent substrates, two or more kinds of particles having different colors and charging characteristics are enclosed, an electric field is applied to the particles from electrodes formed on one or both sides of the substrate, and charged particles having different polarities are different from each other by the Coulomb force. There has been proposed a collision charging method in which the image is displayed in an emergency and moving direction.

1A is a cross-sectional view illustrating a cell structure of a collision charging type electronic paper display device according to the related art. As shown in FIG. 1A, the collision charging type electronic paper display device according to the related art includes an upper substrate 10 and a lower substrate 11 formed of either plastic or glass, and a driving voltage of an element on the substrate. And a partition wall 14 separating the cell from the cell while maintaining a constant gap between the upper electrode 12 and the lower electrode 13 formed of the transparent electrode and the upper substrate 10 and the lower substrate 11. It is composed of

Referring to the collision charging type electronic paper display device according to the prior art, when sufficient voltage is applied to the upper electrode 12 and the lower electrode 13, the charged particles 15, charged according to the applied electrode polarity (( 16) is drawn to each electrode. For example, when a negative voltage is applied to the lower electrode 13 and a positive voltage is applied to the upper electrode 12, the black charged particles 15 charged positively by the Coulomb force are lowered. The white charged particles 16 moving toward the substrate 11 and negatively charged move toward the upper substrate 10. As a result, since the white charged particles 16 are positioned on the upper substrate 10 side, the white charged particles 16 appear white when viewed from the outside. On the contrary, when a positive voltage is applied to the lower electrode 13 and a negative voltage is applied to the upper electrode 12, the black charged particles 15 move toward the upper substrate 10 and become black. It becomes visible.

Regardless of which type of electrophoresis method or collision charging method is used, a technique for forming a charged particle having a fluidity (hereinafter referred to as a 'fluid particle') should be accompanied, and the fluid particle is generally shown in FIG. 1B. As shown, the structure in which the inorganic external additive 4, such as a silicon particle and a coupling agent, is coated on the surface of the polymer particle 1 containing the charge control agent 2 and the pigment | dye / dye 3 is shown.

The flowable particles include an external blending method using a mixer by adding an external additive 4 to a dispersion solvent including a polymer particle, a charge control agent, and a dye / dye (3). have. In the flowable particles in this manner, the polymer particles 1 and the external additives 4 are physically bonded, and due to the limitation of the durability of the physical bonding, the external components easily fall off. When the external additive 4 easily falls in this way, the charged particles cannot sufficiently respond to the same applied voltage, and since the charging characteristics also change easily, there arises a problem of deterioration in image quality. In addition, the longer the use time due to the departure of the external additive, there is a problem that the probability of occurrence of aggregation between the particles increases.

On the other hand, the electrophoretic battery paper display device according to the prior art also the basic structure is similar to the collision charging type electronic paper display device according to the prior art.

The electronic paper display device according to the prior art has a problem that particle aggregation and particle collision are easily generated due to their electrostatic attraction because two or more kinds of particles having different charging characteristics are filled in one cell. .

In addition, there is a problem that the moving speed of the particles is slowed, the reaction speed of the electronic paper is slowed, the driving life is also shortened.

In addition, since the partition wall of the conventional electronic paper display device generally has a rectangular shape, the charged particles are stagnant at each corner or a lot of charged particles are required to fill the spaces between the partition walls, and there is a problem in that the reaction time is slow.

In addition, since particles having two or more different charging characteristics are used, when single particles are used, there is a problem that cannot be driven in the form of a general partition.

In addition, since the electrodes of the conventional electronic paper display apparatus are generally formed in the upper substrate and the lower substrate, there is a problem in that power is consumed even for the partition walls that divide the cells.

In addition, since both the (+) and (-) electrodes are formed, there is a problem in that the interference between the two and thereby the product life is shortened.

In addition, the conventional method of forming the partition wall is based on a photolithography method using a photoresist (PR), as shown in Figures 2a to 2d. That is, as shown in FIG. 2A, the photoresist 300 is coated with a material for forming a partition on the substrate 100 on which the electrode 200 is formed, and as shown in FIG. 2B, a region in which the partition is to be formed is divided. In order to form a pattern 400 to block the light on the photoresist 300 with a pre-made photomask or the like. Thereafter, as shown in FIG. 2C, only a region distinguished by the pattern 400 is etched to form a partition 500 as illustrated in FIG. 2D. Since the method of forming the barrier rib 500 using the photolithography method requires an exposure process using a separate light, the manufacturing method is complicated, and a separate exposure apparatus is required for the exposure process. There is a problem that the manufacturing process is cumbersome.

In addition, since the bulkhead has been mainly etched by a photo process, photoresist (PR) has been most widely used as a bulkhead material, and polyethylene terephthalate (PET) and polyether sulfone ( Polymers such as PES), polyethylene (PE), polycarbonate (PC), polypropylene (PP) or inorganic materials.

However, conventional inorganic or polymer materials, including photoresist, have lacked adhesion to a substrate or an electrode. Even when the adhesive is applied to the partition wall, when the adhesive force with the substrate or the electrode is deteriorated and the shape of the display device is deformed and bent, the partition wall is frequently lifted. This has a problem of lowering the overall quality of the display device.

For this reason, in the method of manufacturing an electronic paper display device, there is a demand for a partition wall formation method in which the partition wall can be formed more easily and simply, and the adhesion between the substrate and the electrode does not easily fall.

The present invention is to solve the above problems, an object of the present invention, by chemically bonding titanium dioxide (TiO ₂ ) and silica (SiO ₂ ) to the monomer, unlike the conventional chemical bonding, the durability of the bond is An object of the present invention is to prepare fluid particles having excellent fluidity and excellent flowability, and to use such fluid particles as single particles to prevent collisions between particles having different charging characteristics and aggregation of particles due to electrostatic attraction.

In addition, by using tetraol-malbutyl titanate, the reflectance is greatly improved, the particle pH can be easily controlled by adjusting to the optimum pH, and by using a dispersion stabilizer, the dispersion stability of particles is increased, and the aggregation between particles is generated. The purpose is to control.

In addition, the use of a single particle provides an electronic paper display device which increases the durability of the device, and aims to improve the aperture ratio and contrast ratio of the display device while using the single particle.

In addition, it is an object to suppress the interference phenomenon between charges by adjusting the position, size and charging characteristics of the electrode. In addition, an object of the present invention is to provide an electronic paper display device that reduces power consumption, simplifies configuration, increases durability of the device, and maximizes the effect of using single particles.

In addition, another object of the present invention is to form a partition wall by using a separate mold, and to form the partition wall quickly and in large quantities without the complicated and difficult photo process work as in the prior art. It is an object of the present invention to provide an electronic paper display device having high elasticity and having high bonding strength with the substrate and the electrode.

Electronic paper display apparatus using the TEOS fluid particles according to the present invention for achieving the above object, the partition wall forming a cell between the upper substrate and the lower substrate arranged at a predetermined interval, and charged inside the cell An electronic paper display device filled with particles, comprising: an electrode formed in contact with at least one of the upper substrate and the lower substrate; A first partition wall including at least one hole and positioned between the upper substrate and the lower substrate and disposed to face the upper substrate and the lower substrate, respectively; A second partition wall that divides pixels between the upper substrate and the lower substrate and connects the upper substrate and the lower substrate; Charged particles filled in a cell formed by the first and second partition walls; The charged particles are based on a solvent and 100 parts by weight of a solvent, 5 to 20 parts by weight of monomer, 0.1 to 3 parts by weight of polymerization initiator, 0.5 to 15 parts by weight of dispersion stabilizer, 0.5 to 2 parts by weight of tetraolmalbutyl titanate, and tetraethylortho. Silicate (Tetraethyl Ortho silicate) is characterized in that it comprises 0.7 to 5 parts by weight.

In addition, the projection formed on the lower substrate surface, the protrusion disposed facing the hole formed in the first partition wall; characterized in that the polymerization initiator further comprises 2,2'-azobis (isobutyramidine) hydro Chloride (2,2'-azobis (isobutyramidine) hydro

chloride).

In addition, the charged particles are single particles having the same charging characteristics, characterized in that the hydrogen ion index (pH) is 8 to 13, the hole formed in the first partition wall is the width of the widest portion is 2 to 5㎛ , The width of the narrowest part is characterized by 1 to 2㎛.

In addition, the inside of the hole formed in the first partition wall is formed so that the diameter becomes narrower toward the center, the cross section of the hole formed in the first partition wall is characterized in that it consists of a smooth curve.

Method for manufacturing an electronic paper display device using the TEOS fluid particles of the present invention for achieving the above object, the partition wall for forming a cell between the upper substrate and the lower substrate arranged at a predetermined interval, and the inside of the cell A method for manufacturing an electronic paper display device filled with charged particles, the method comprising: forming an electrode on at least one of the upper substrate and the lower substrate; A first partition wall forming step including at least one hole, wherein the first partition wall is formed between the upper substrate and the lower substrate and forms a partition wall disposed on the upper substrate and the lower substrate, respectively; A second partition wall forming step of dividing pixels between the upper substrate and the lower substrate and forming a partition wall connecting the upper substrate and the lower substrate; A projection forming step formed on a surface of the lower substrate and forming a projection disposed to face the hole formed in the first partition wall; A particle forming step of forming the charged particles; A filling step of filling the charged particles into cells formed by the first and second partition walls; And bonding the upper substrate to the lower substrate so that the upper substrate and the lower substrate face each other.

The first partition wall forming step, the step of preparing a mold, and applying a curable composition on the mold; A curing step of curing the applied curable composition by irradiating ultraviolet rays or by applying heat; And a separating step of separating the cured curable composition from a mold to form a partition wall.

In addition, the second partition wall forming step, preparing a mold, the coating step of applying a curable composition on the mold; Positioning the lower substrate such that the applied curable composition and the lower substrate face each other, and then curing the curable composition by irradiating ultraviolet rays or applying heat to the curable composition; And separating the curable composition and the lower substrate from the mold to form a partition wall.

The particle forming step may include a core forming step of forming a core by mixing 5 to 20 parts by weight of monomer, 0.1 to 3 parts by weight of polymerization initiator, and 0.5 to 15 parts by weight of dispersion stabilizer based on a solvent and 100 parts by weight of a solvent; A dissolution step of dissolving tetranomal butyl titanate in ethanol (EtOH); A first mixing step of preparing a first mixed solution by mixing tetraethylorthosilicate in the core with 0.7 to 3 parts by weight based on 100 parts by weight of the solvent; A second mixing step of preparing a second mixed solution by mixing 0.5 to 2 parts by weight of tetranomal butyl titanate with respect to 100 parts by weight of the solvent to the first mixed solution; the second mixed solution at a temperature of 40 to 90 ° C. A polymerization step of polymerizing in 30 to 50 hours to prepare flowable particles; A drying step of drying the flowable particles; A surface treatment step of treating the surface of the flowable particles with silane; In the first mixing step or the second mixing step, pH adjustment step of adjusting the pH of the hydrogen ion (pH) to 8 to 13 by adding an acid or alkaline solution to the first mixture solution or the second mixture solution; It is characterized in that it comprises a; particle selection step of selecting particles using a sieve made of a hole of 10 to 30㎛.

In the filling step, the charged particles are single particles having the same charging characteristics, characterized in that the hydrogen ion index (pH) is 8 to 13, in the first partition wall forming step, the inside of the hole formed in the first partition wall The diameter is formed to become narrower toward the center, characterized in that the cross section of the hole formed in the first partition wall has a smooth curved shape.

In the first partition wall forming step, the hole formed in the first partition wall is characterized in that the width of the widest portion is 2 to 5㎛, the width of the narrowest portion is 1 to 2㎛.

According to the electronic paper display device using the TEOS fluid particles of the present invention and a method for manufacturing the same, the present invention is to solve the above problems, an object of the present invention, titanium dioxide (TiO ₂ ) and silica (SiO ₂ ) in the monomer By chemically bonding, by means of chemical bonding unlike in the prior art, it is possible to produce flowable particles having excellent bonding durability and excellent fluidity, and using such flowable particles as single particles, between particles having different charging characteristics There is an advantage of preventing agglomeration between particles due to collision and electrostatic attraction.

In addition, by using tetraol-malbutyl titanate, the reflectance is greatly improved, the particle pH can be easily controlled by adjusting to the optimum pH, and by using a dispersion stabilizer, the dispersion stability of particles is increased, and the aggregation between particles is generated. There is an advantage to control.

In addition, unlike conventional, by using tetraethyl ortho silicate, the conversion to silica (SiO ₂ ) is high, there is an advantage that the formation of particles is easy.

In addition, by using the single particles, it is possible to provide an electronic paper display device having increased durability of the device, and to improve the aperture ratio and contrast ratio of the display device while using the single particles.

In addition, it is an object to suppress the interference phenomenon between charges by adjusting the position, size and charging characteristics of the electrode. In addition, the power consumption is reduced, and the configuration is simplified to increase the durability of the device, there is an advantage that can maximize the effect of using a single particle.

In addition, by forming a partition using a separate mold, it is intended to form a bulkhead quickly and in large quantities without the complicated and difficult photo-processing work as in the prior art, by forming a partition by the curable composition, has a high elasticity, There is an advantage of having a high bonding strength with the substrate and the electrode.

EMBODIMENT OF THE INVENTION Hereinafter, the electronic paper display apparatus using TEOS fluid particle | grains, and its manufacturing method by using this invention are demonstrated in detail with reference to attached drawing. 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.

3 is a cross-sectional view and a plan view illustrating an electronic paper display device according to a first embodiment of the present invention, and FIG. 4 is a plan view illustrating a first partition of the electronic paper display device according to an embodiment of the present invention.

As shown in FIG. 3, the electronic paper display device of the present invention includes an upper substrate 20, a lower substrate 28, and an upper substrate 20 and the lower substrate 28 arranged to face each other at a predetermined interval. It includes an electrode (21a, 21b) formed in contact with at least one, at least one hole (22), located between the upper substrate 20 and the lower substrate 28, the upper substrate 20 And dividing pixels between the first partition wall 23, the upper substrate 20, and the lower substrate 28, which are disposed to face each of the lower substrates 28, and the upper substrate 20 and the lower substrate ( The second partition 24 connecting the 28, the charged particles 26 filled in the cell 25 formed by the first partition 23 and the second partition 24, and the lower substrate 28. It is formed on the surface, and comprises a projection 27 disposed to face the hole 22 formed in the first partition wall (23).

Here, the electrodes 21a and 21b are divided into an upper electrode 21a in contact with the upper substrate 20 and a lower electrode 21b in contact with the lower substrate 27. The upper electrode 21a has a charging property opposite to that of the charged particle 26, thereby attracting the charged particle 26, and the lower electrode 21b is the same as the charged particle 26. By having a charging characteristic, it serves to push the charged particles 26. By adjusting the amount of charge applied to the electrode, both the upper electrode 21a and the lower electrode 21b may be provided or only one of the upper electrode 21a or the lower electrode 21b may be provided.

By installing the electrode 21 only on either the upper electrode 21a or the lower electrode 21b as described above, the manufacturing process of the device is reduced, and as the material cost of the transparent electrode is reduced, the overall manufacturing cost is reduced. There is an economic advantage, and by simplifying the operation of the device, there is an advantage that the device life is increased. That is, there is an effect of maximizing the advantage of using a single particle through electrode formation.

In addition, the partition wall is composed of a first partition 23 and a second partition 24, the first partition 23 includes at least one hole (22), and the upper substrate 20 and Located between the lower substrate 28, it is disposed opposite each of the upper substrate 20 and the lower substrate 28. The hole 22 may be one or more, and the larger the number, the more smoothly the movement of the charging element 26, but the projections 27 must be made as much, so that not only the manufacturing cost increases but also the contrast of the display device. There is a danger of rain. Therefore, it is preferable to include 4 to 9 holes 22.

It is preferable that the width of the widest portion of the hole 22 formed in the first partition 23 is 3 to 7 µm, and more preferably, the width is 3 to 5 µm. If the width is less than 3 μm, the charged particles 26 are difficult to move through the holes 22, and thus the fluidity decreases, so that the reaction rate of the display device is lowered. When the width exceeds 5 μm, the display device There is a problem of low contrast ratio. On the other hand, it is preferable that the width of the narrowest part of the hole 22 formed in the first partition 23 is 1 to 2 mu m, more preferably 1.5 mu m in width. When the width is less than 1 μm, the charged particles 26 are difficult or impossible to pass through the holes 22, so that the display device may not operate or the reaction rate may drop, and the width may exceed 2 μm. There is a problem that the contrast ratio of the display device is lowered.

In addition, the inside of the hole 22 formed in the first partition 23 is formed so that the diameter becomes narrower toward the center, the cross section of the hole 22 formed in the first partition 23 has a smooth curved shape. When the diameter of the hole 22 is formed to become narrower toward the center, the opening and the movement of the charged particles 26 can be smoothly increased, and the aperture ratio and contrast ratio of the display device can be improved. If the shape is not a straight line, the charging particles 26 can be prevented from stagnating at the corners, and the charging particles 26 can be moved smoothly, thereby improving the response speed of the display device. Because.

The second partition wall 24 connects the upper substrate 20 and the lower substrate 28 to separate pixels.

The first and second partitions 23 and 24 are made of black in contrast to the color of the charged particles 26 so that the screen is displayed in black when the charged particles 26 are shielded in the eyes of the user. Be sure to

In addition, referring to the charged particles 26 filled in the cell 25, the charged particles 25 is composed of a single particle having the same charging characteristics. In the related art, as shown in FIG. 1A, two kinds of charged particles 15 and 16 charged in positive (+) and negative (-) and having different kinds of colors of black and white, respectively, are included in one cell. Since particles having two or more different charging characteristics are filled, the particles easily collide with each other due to their electrostatic attraction, and have a disadvantage in that the durability of the device is lowered and the reaction speed is also slowed. In order to solve this problem, in the present invention, the charged particles 26 filled in the cell 25 have the same charging characteristics, and by using single particles having only one kind of color such as white, the collision and aggregation of particles are remarkably occurred. Reduction, thereby improving the durability of the device, there is an advantage that the reaction speed is also improved.

In addition, the charged particles 26 are flowable particles, and include a solvent, a monomer, a polymerization initiator, tetranomal butyl titanate (Ti (Obu) ₄ ), and tetraethyl ortho silicate.

The solvent is a mixture of water and ethanol, it is preferable to include 20 to 40% by weight of water, 40 to 80% by weight of ethanol. More preferably, it is most effective to include 28 to 32% by weight of water and 65 to 75% by weight of ethanol. If the content of water and ethanol is out of the range of the above preferred content, the dispersion polymerization is not performed smoothly, therefore, the combination of tetranomal butyl titanate (Ti (Obu) ₄ ) and tetraethylorthosilicate (TEOS) is also normal. There is a problem that is difficult to form.

The monomer is not particularly limited as long as it is capable of non-emulsifying polymerization, but methyl methacrylate, ethylene terephthalate, styrene sulfonate, vinyl acetate, methyl styrene, acrylic acid, butyl methacrylate, ethyl methacrylate, 2-ethyl The monomer particles such as hexyl acrylate and N-vinyl caprolactam may be used alone or in a copolymerized manner. Preferably, styrene is most effective.

The content of the monomer is preferably 5 to 20 parts by weight, more preferably 8 to 15 parts by weight with respect to 100 parts by weight of the solvent. When the monomer is added in less than 5 parts by weight, there is a problem that the resulting polymer particles are less likely to be charged, and when it exceeds 20 parts by weight, silica and titanium dioxide (TiO ₂ ) as external additives sufficiently cover the surface of the polymer particles. There is a problem that the durability and fluidity is deteriorated due to not wrapped.

As described above, in the present invention, due to the interaction between the polymerization initiator and silica and titanium dioxide (TiO ₂ ), silica and titanium dioxide (TiO ₂ ) are chemically bonded to the surface of the polymer particles produced through the polymerization of the monomer. This is accomplished by a mechanism whereby the synthesis initiator is a cation, and the negative charge of silica and titanium dioxide (TiO ₂ ) is combined to have strong ionic bonds.

Polymerization initiators used herein include all free radical polymerization initiators capable of triggering non-emulsification polymerization generally used. The polymerization initiator may in principle comprise both peroxides and azo compounds, said peroxides being in principle inorganic peroxides such as hydrogen peroxide or peroxodisulfate such as mono- or di-alkali metals of peroxodisulfate Salts or ammonium salts, examples of which are mono- and di-sodium and -potassium salts, or ammonium salts, or may be organic peroxides such as alkyl hydroperoxides, for example tert-butyl, p- Menthyl and cumyl hydroperoxide, and also dialkyl or diaryl peroxides, such as di-tert-butyl peroxide or dicumyl peroxide. The compounds used are mainly 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile) and 2,2'-azobis (amidinopropyl) Dihydrochloride). Preferably, 2,2'-azobis (isobutyramidine) hydrochloride (2,2'-azobis (isobutyramidine) hydrochloride) (hereinafter referred to as 'AIBA') is most efficiently used as a polymerization initiator. AIBA has the following structure.

In particular, in the present invention, a bond is formed due to the interaction between the cation initiator AIBA and silica and titanium dioxide (TiO ₂ ), which is a basic environment because the silica particles have a negative charge at a pH of 3 or higher. This is because the anion of the silica particles and the cation by the amine group contained in the AIBA is bonded to perform the chemical ion bonding.

The polymerization initiator preferably contains 0.1 to 3 parts by weight, more preferably 1 to 2 parts by weight based on 100 parts by weight of the solvent. If the polymerization initiator is less than 0.1 part by weight, the interaction between silica and titanium dioxide (TiO ₂ ) is difficult, and no bond is formed. When the polymerization initiator is more than 3 parts by weight, the cation is excessive, so that the bonding strength is weak and economical inferior. there is a problem.

In addition, since the present invention forms the particles by dispersion polymerization, in order to achieve a dispersion polymerization reaction, a dispersion stabilizer is included. As a dispersion stabilizer, various materials can be used, but it is effective to use poly vinyl pyrrolidone (hereinafter, referred to as 'PVP') most preferably after several experiments. PVP increases the dispersion stability of the particles.

Herein, the dispersion stabilizer preferably contains 0.5 to 15 parts by weight, and more preferably 5 to 8 parts by weight based on 100 parts by weight of the solvent. When the dispersion stabilizer is less than 0.5 parts by weight, the dispersion of the monomer is not good, the dispersion polymerization reaction is not performed smoothly, there is a problem that the size of the flowable particles are uneven, the possibility of aggregation between particles increases.

5 is an experimental result of whether PVP affects the aggregation between particles during the formation of flowable particles. When PVP is present (a), PVP is present and the hydrogen ion index (pH) is adjusted to 10 (b), PVP In the case of (c) there was no SEM to compare the aggregation of the particles. As shown in Figure 5, (a), (b) with PVP was significantly removed the aggregation of the particles compared to (c), fine but the case of (b) adjusted to a pH of 10 is the most particles Showed less aggregation. This proved that PVP had the most excellent effect on eliminating agglomeration of particles.

In addition, Figure 6 is an experimental result of how the PVP and pH affects the particle size and selectivity, Figure 6a is a core particle in the presence of PVP, Figure 6b is a core particle in the absence of PVP, Figure 6c Flowable particles with PVP, FIG. 6D is a flowable particle with PVP and pH 10, FIG. 6E is a graph of the size and level of flowable particles with no PVP and pH 10. As shown in FIG. 6, when the PVP is present, the particles appear to be evenly uniform, and when the pH is maintained at 10, the size of the particles is also small and even. Therefore, in the case of FIG. 4D where PVP is present and the pH is maintained at 10, it is proved by the experimental results that the performance shows the best flowable particles, so that the performance of the best flowable particles is ensured in the case of the scope of the present invention. Able to know.

In addition, Figure 7 is a graph showing the results of the experiment according to the presence or absence of PVP and pH control by infrared spectroscopy (hereinafter referred to as IR). Again in FIG. 3 (a), (b) , (c) and that a new peak appeared when viewed as a strong peak appears in the result, 1600 ~ 2000cm ^-1 experiment under the conditions, as Ti-O-Si bonds are formed Since it is estimated, (b) also falls within the scope of the present invention, it can be seen that the bond is best formed.

8 is a graph measuring the inorganic content according to the presence or absence of PVP under the same conditions as (b) and (c) of FIG. 7, and (b), which also belongs to the scope of the present invention, was found to have the highest inorganic content. The results show that the most bond is formed.

The flowable particle composition of the present invention includes tetraolmalbutyl titanate (Ti (Obu) ₄ ), which is converted into a form of titanium dioxide (TiO ₂ ) in the process of mixing with the monomer, thereby binding to the monomer, and the flowable particle It is effective to greatly increase the reflectance of. This reflectivity increase effect can be seen through the reflectance comparison test results in Table 1 below.

TABLE 1

Reflectance (%) White board 100.0 Polymer 77.5 Polymer-SiO ₂ 85.3 Polymer-SiO ₂ , TiO ₂ 92.0 to 98.0

In order to stabilize the bonding between the monomer and the silica and titanium dioxide (TiO ₂ ), the hydrogen ion index (pH) is preferably maintained at 8 to 13, and most preferably at 10 to 11 is effective. When the hydrogen ion index (pH) is less than 8 or more than 13, the coupling reaction between the monomer and silica and titanium dioxide (TiO ₂ ) does not occur well, and thus there is a problem in that stable fluid particles cannot be prepared.

Several experiments have shown that the particle size distribution is good and the weight ratio of tetraol-butylbutyl titanate (Ti (Obu) ₄ ) to tetraethyl orthosilicate is preferred for good interaction of silica and titanium dioxide with monomers. Is 1: 1 to 1:10, most preferably 1: 4 to 1: 7. When tetraol-malbutyl titanate (Ti (Obu) ₄ ) is contained in more than the weight ratio, there is a problem in that a reverse reaction occurs and is converted into monomers. As the ethyl orthosilicate content increases, there is a problem that the inside of the fluid particles becomes hollow.

Experimental results on the effect of the content ratio of tetraethylorthosilicate and tetraolmalbutyl titanate on the particles are shown in FIGS. 9 to 13.

As shown in FIG. 9, as the content of tetranomalbutyl titanate was increased, it was found that agglomerated particles (TiO ₂ ) existed around the bound flowable particles, which is titanium (Ti) _2. As a phenomenon that appears because the reaction rate is faster than), it can be seen that the aggregation phenomenon is the least when maintaining the content ratio of tetraethyl orthosilicate and tetranomal butyl titanate of the present invention as described above.

In addition, the experimental results of FIG. 10 in which only PVP is present under the same conditions as those of FIG. 9 show that particles are more stable than those of FIG. 9, and once again, it is possible to form more stable particles when PVP is present. there was.

Tetraolmalbutyl titanate is converted to titanium dioxide (TiO ₂ ), tetraethylorthosilicate (TEOS) to silica (SiO ₂ ) is combined with the monomer, Figure 11 and Table 2 is tetraolmalbutyl titanate and tetra As a result of experiments on the conversion rate according to the content of ethyl orthosilicate (TEOS), it can be seen that the conversion ratio decreases as the content of tetranomal butyl titanate increases. Therefore, it is necessary to maintain the content within the scope of the present invention to properly convert and react, thereby forming a flowable particle combined with a monomer, tetranomal butyl titanate, tetraethyl orthosilicate.

The conversion of tetraolmalbutyl titanate is about 23.5% and the conversion of tetraethylorthosilicate is about 28.9%.

TABLE 2

Ti (Obu) ₄ (g) TEOS (g) TEOS / Ti (Obu) ₄ Volume switched (g) % Of monomer 10g 0 2.5 - 0.72 7.2 0.2 2.3 10 0.71 7.1 0.5 2 4 0.70 7.0 One 1.5 1.5 0.67 6.7 1.67 0.83 0.5 0.63 6.3 2.5 0 - 0.59 5.9

12A is a core particle before tetraethylorthosilicate and tetranomalbutyl titanate are mixed, and FIG. 12B is a case in which the content ratio of TEOS / Ti (Obu) ₄ is 10. FIG. 12C is a diagram of TEOS / Ti (Obu) ₄ . When the content ratio is 4, FIG. 12d illustrates a case in which the content ratio of TEOS / Ti (Obu) ₄ is 1.5, and FIG. 12e illustrates a case in which the content ratio of TEOS / Ti (Obu) ₄ is 0.5. As a result of the comparison, in the case of FIGS. 12A and 12B belonging to the TEOS / Ti (Obu) ₄ content range of the present invention, the size of the particles appeared small and evenly, indicating that the particles were well bonded.

13 is a graph measuring the initial driving voltage (v) according to the content ratio of tetraethylorthosilicate and tetranomal butyl titanate, when TEOS / Ti (Obu) ₄ content ratio is 4 (a), TEOS / Ti Comparing (b) in the case of (Obu) ₄ content ratio of 1.5, the initial operating voltage of (a) in the TEOS / Ti (Obu) ₄ content range of the present invention is 120v, which is much lower than 160v of (b). It can be seen that it represents the driving voltage.

Accordingly, the tetraolmalbutyl titanate (Ti (Obu) ₄ ) preferably contains 0.5 to 2 parts by weight based on 100 parts by weight of the solvent, and the tetraethylorthosilicate is 0.7 to 5 parts by weight of 100 parts by weight of the solvent. It is preferred to include parts by weight.

In addition, the flowable particle composition according to the present invention may include a charge control agent such as a positive (+) charge control agent or a negative (-) charge control agent, if necessary, and an organic colorant. Or inorganic colorants may be additionally included. The charge control agent may be a positively charged charge control agent such as a nigrosine dye, a triphenylmethane compound, a quaternary ammonium salt compound, a polyamine resin or an imidazole derivative, a salicylic acid metal complex, or a metal (metal ion or metal). Negative charge charge control agents such as azo dyes, oil-soluble dyes containing metals, quaternary ammonium salt compounds, calix arene compounds, boron-containing compounds (boron benzyl complex) or nitroimidazole derivatives; In addition, any charge control agent usable for the flowable particles for the electronic paper image display device may be included. The colorant may be an organic colorant such as nigrosine, methylene blue, quinoline yellow, or rose bengal, titanium oxide, zinc oxide, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica or calcium silicate. , Alumina white, cadmium yellow, cadmium red, cadmium orange, titanium yellow, wire blue, ultramarine blue, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder or aluminum powder The same inorganic colorant may be included, in addition, various colorants may be included without limitation.

In addition, the charged particles 26, the first partition 23 and the second partition 24 is configured to be contrasted with each other in black (White) or white (white) representing the contrast, and in addition, if necessary It can be used as particles with various colors. The charged particles 26, the first partition 23 and the second partition 24 may be contrasted with each other in black or white (representative contrast), and other various as necessary It can be used as colored particles.

As the projections 27 move the charged particles 26 through the holes 22 of the first partition 23, the charged particles 26 are positioned directly under the holes 22, thereby charging particles 26. ) Is formed to solve the problem of not being shielded. The protrusions 27 are disposed to face the holes 22, so that the charged particles 26 may not be located directly below the holes 22, so that the charged particles 26 are completely shielded from the eyes of the user.

The first and second partitions 23 and 24 are made of black in contrast to the color of the charged particles 26 so that the screen is displayed in black when the charged particles 26 are shielded in the eyes of the user. Be sure to

That is, the white particles 29a are displayed to the user when the charged particles 26 are raised toward the upper substrate 20, and the black particles 29b are displayed to the user when the charged particles 26 are lowered toward the lower substrate 28. Is displayed.

Next, with respect to a method for manufacturing an electronic paper display device using the TEOS fluid particles to produce an electronic paper display device using the TEOS fluid particles according to the present invention configured as described above, an embodiment of the present invention 14 to FIG. This will be explained with reference to 24.

As shown in FIG. 14, in the method of manufacturing an electronic paper display device according to the present invention, an electrode forming step (S10) of forming an electrode on at least one of the upper substrate and the lower substrate, at least one hole ( a first partition wall forming step S20 between the upper substrate and the lower substrate and forming a partition wall disposed to face the upper substrate and the lower substrate, and between the upper substrate and the lower substrate. The second partition wall forming step (S30) for dividing the pixel, and forming a partition wall connecting the upper substrate and the lower substrate, a protrusion formed on the surface of the lower substrate and disposed to face the hole formed in the first partition wall ( A projection forming step (S40) for forming a projection, a particle forming step (S50) for forming a charged particle, and a charging stage for filling charged particles in a cell formed by the first and second partition walls. (S60), comprises the cementation step (S70) of the lower substrate attached to each other and to the upper substrate so that the upper substrate and the lower substrate opposed to each other.

In addition, at least one of the first partition wall forming step S20 or the second partition wall forming step S30 may include an application step S21 and S31 of preparing a mold and applying a curable composition on the mold. After placing the lower substrate so that the curable composition and the lower substrate face each other, the curing step (S22, S32) to cure the curable composition by applying ultraviolet rays or heat to the curable composition, and the curable composition and the cured lower substrate It comprises a separation step (S23, S33) to form a partition by separating.

Here, the electrode forming step (S10) is a step of forming an electrode in contact with at least one of the upper substrate and the lower substrate. An electrode (not shown) is divided into an upper electrode in contact with an upper substrate and a lower electrode in contact with a lower substrate. The upper electrode has a charging property opposite to that of the charged particles, thereby attracting the charged particles, and the lower electrode has the same charging characteristics as the charged particles, thereby pushing out the charged particles. . By adjusting the amount of charge applied to the electrode, both the upper electrode and the lower field may be provided, or only one of the upper electrode and the lower electrode may be provided.

The first partition wall forming step S20 includes at least one hole and is formed between the upper substrate and the lower substrate and forms a partition wall disposed to face each of the upper substrate and the lower substrate.

As shown in FIG. 3 and FIGS. 15A to 15F, the first partition wall forming step S20 includes an application step S21, a curing step S22, and a separation step S23.

Here, the application step (S21) is a step of preparing the mold 40, as shown in Figure 15a. This is to provide a place or space where the partition wall is formed through the mold 40. In other words, the barrier rib is not formed directly on the substrate, but indirectly, and the barrier rib is attached to the substrate by a separate indirect mold (mould).

Such a mold 40 preferably forms a structure on the surface so as to form a desired partition by dry etching, wet etching, or sanding processes. In the present invention, since the structure of the mold 40 is to provide a space for forming the partition, the structure is formed at intervals corresponding to the distance between the partitions to be made.

In addition, a curable composition 41 is applied to the mold 40 as shown in FIG. 15B. The curable composition 41 used in the present invention may use any composition that can be cured, but mainly refers to a polymer that is cured by light, and is distinguished from a thermosetting polymer or a moisture curable polymer that is cured by heat or moisture. Thermosetting polymers and water-curable polymers are not suitable for flexible electronic paper because they harden after being cured by heat or moisture and are easily broken apart when bent. Therefore, the photocurable polymer is selected as the partition material in this embodiment. will be. Such a photocurable polymer may be included as long as it is known to those skilled in the art without particular limitation, and among these, the photocurable polymer preferably includes a UV curing agent for photocuring. For example, the photocurable polymer is preferably an ester or ether type polymer in which acrylyl or allyl system is bonded to the end of polyethylene glycol (PEG) or polypropylene glycol (PPG), or not polyethylene glycol (PEG). Urethane-type photocurable polymers formed by reacting with oxidized polyoxyethyllene bisamine and acrylyl are also possible. The method of applying such a curable composition 41 to the mold 40 according to the present invention is also not particularly limited.

The curing step (S22) is a step of curing the curable composition 41 by applying ultraviolet rays or applying heat to the applied curable composition 41 as shown in FIG. 15C. Here, irradiating ultraviolet rays or applying heat is for curing the curable composition 41 according to the present invention. When the curable composition 41 is irradiated with light such as UV, the curable composition 41 is cured while being partitioned. Will have the shape of. Conventionally, in order to form a partition wall, the partition material is directly applied onto a substrate or an electrode, and the partition wall is etched in a desired shape. However, according to the present invention, the method of using the curing of the mold and the curable composition 41 is performed once. 40 is an indirect method of injecting a partition forming material and attaching it to the substrate structure. This has the economical advantage that the bulkhead can be easily and easily formed in bulk and the mold 40, which is an indirect mold frame, can be reused over and over again.

Separation step (S23) is a step of forming a first partition by separating the cured curable composition 41 from the mold 40, as shown in Figure 15d. In order to separate the cured curable composition 41 from the mold 40, the cured curable composition 41 and the mold 40 need to be separated by pulling up and down. ) May further include a material such as a lubricant before injecting the curable composition 41 into the mold 40. The method of separating is not particularly limited.

The first partition wall formed through the separation step S23 has a shape as shown in FIG. 15E, and the first partition wall is used to shield the charged particles most effectively by using a single charged particle having one electric charge.

As shown in FIGS. 3 and 15F, the first partition walls 23 and 43 formed by the first partition wall forming step include at least one hole 22 and 42, and the upper substrate 20 is formed. And disposed between the upper substrate 20 and the lower substrate 28, respectively, between the upper substrate 20 and the lower substrate 28. The holes 22 and 42 may be one or more, and as the number of holes 22 and 42 increases, the movement of the charged particles 26 is smooth, but the protrusions 27 must be made as much, so that not only the manufacturing cost increases but also There is a concern that the contrast ratio may be lowered. Therefore, it is preferable to include 4 to 9 holes 22 and 42.

The holes 22 and 42 formed in the first partitions 23 and 43 preferably have a width of 3 to 7 µm, and more preferably a width of 3 to 5 µm. If the width is less than 3 μm, the charged particles 26 are difficult to move through the holes 22 and 42, and the fluidity is lowered. Therefore, the reaction rate of the display device is lowered. When the width exceeds 5 μm, There is a problem that the contrast ratio of the display device is lowered. On the other hand, the width of the narrowest portion of the holes 22, 42 formed in the first partitions 23, 43 is preferably 1 to 2 mu m, more preferably 1.5 mu m in width. If the width is less than 1 μm, the charged particles 26 may be difficult or impossible to pass through the holes 22 and 42, and thus, the display device may not operate or the reaction rate may decrease. The width may exceed 2 μm. In this case, there is a problem that the contrast ratio of the display device is lowered.

In addition, the insides of the holes 22 and 42 formed in the first partitions 23 and 43 are formed to have narrower diameters toward the center portion, and the holes 22 and 42 formed in the first partitions 23 and 43 are formed. The cross section is made of smooth curves. When the diameters of the holes 22 and 42 become narrower toward the center portion, the holes 22 and 42 can be smoothly moved up and down, while improving the aperture ratio and contrast ratio of the display device. When the cross section of the cross section 42 is formed in a curved shape rather than a straight line, the charged particles 26 can be prevented from stagnating at the corners, and the charged particles 26 can move smoothly, thereby improving the reaction speed of the display device. This is because there is an advantage.

In the second partition wall forming step S30, the pixel is divided between the upper substrate and the lower substrate, and a partition wall connecting the upper substrate and the lower substrate is formed.

In addition, the protrusion forming step S40 is a step of forming a protrusion formed on the lower substrate surface and disposed to face the hole formed in the first partition wall.

The second partition wall forming step S30 and the projection forming step S40 may be formed through respective forming steps, but in the present embodiment, the second partition wall and the projection are simultaneously formed.

The second partition wall forming step S30 and the protrusion forming step S40 include an application step S31, a curing step S32, and a separation step S33, as illustrated in FIGS. 3 and 16A to 16E. Is done.

Here, the application step (S31) is a step of preparing the mold 50, as shown in Figure 16a. This is to provide a place or space in which the partition wall is formed through the mold 50. In other words, the barrier rib is not directly formed on the substrate, but indirectly, and the barrier rib is attached to the substrate by a separate indirect mold (mould).

Such a mold 50 is preferably formed on the surface to form the desired partition wall by dry etching, wet etching or sanding (sanding) process. In the present invention, since the structure of the mold 50 is to provide a space for forming the partition, the structure is formed at intervals corresponding to the distance between the partitions to be made.

In addition, the curable composition 51 is applied to the mold 50 as shown in FIG. 16B. The curable composition 51 used in the present invention may be any composition that can be cured, but mainly refers to a polymer that is cured by light, and is distinguished from a thermosetting polymer or a moisture curable polymer that is cured by heat or moisture. Thermosetting polymers and water-curable polymers are not suitable for flexible electronic paper because they harden after being cured by heat or moisture and are easily broken apart when bent. Therefore, the photocurable polymer is selected as the partition material in this embodiment. will be. Such a photocurable polymer may be included as long as it is known to those skilled in the art without particular limitation, and among these, the photocurable polymer preferably includes a UV curing agent for photocuring. For example, the photocurable polymer is preferably an ester or ether type polymer in which acrylyl or allyl system is bonded to the end of polyethylene glycol (PEG) or polypropylene glycol (PPG), or not polyethylene glycol (PEG). Urethane-type photocurable polymers formed by reacting with oxidized polyoxyethyllene bisamine and acrylyl are also possible. The method of applying such a curable composition 51 to the mold 50 according to the present invention is also not particularly limited.

The curing step (S32) is the curable composition by placing the lower substrate 53 so that the applied curable composition 51 and the lower substrate 53 face each other, as shown in Figure 16c, by irradiating ultraviolet rays or applying heat Curing the composition 51 is a step. Here, irradiating ultraviolet light or applying heat is for curing the curable composition 51 according to the present invention. When the curable composition 51 is irradiated with light such as UV, the curable composition 51 is cured while being partitioned. Will have the shape of. Conventionally, in order to form a partition wall, the partition material is directly applied onto a substrate or an electrode, and the partition wall is etched in a desired shape. 50) is an indirect method of injecting the barrier rib forming material and attaching it to the substrate structure. This has the economical advantage that the bulkhead can be easily and easily formed in bulk, and the mold 50, which is an indirect mold frame, can be reused continuously.

In the separating step S33, as shown in FIG. 16D, the cured curable composition 51 and the lower substrate 53 are separated from the mold 50 to form the second partition wall and the protrusion 52. In order to separate the cured curable composition 51 from the mold 50, the cured curable composition 51 and the mold 50 must be separated by pulling up and down, and the mold 50 may be separated to facilitate the separation. ) May further include a material such as a lubricant before injecting the curable composition 51 into the mold 50. The method of separating is not particularly limited. The second partition wall divides the pixel, and as the projection 52 moves through the hole of the first partition wall, the charged particles are located directly under the hole, whereby the charged particles are not shielded. Is formed to solve the problem. The protrusion 25 is disposed to face the hole, so that the charged particles cannot be located directly under the hole, so that the charged particles are completely shielded from the eyes of the user.

Particle forming step (S50) is a step of forming a charged particle. As shown in Figure 14, the particle forming step (S50) is the core forming step (S51), dissolution step (S52), the first mixing step (S53), pH control step (S54), the second mixing step (S55) , Polymerization step (S56), drying step (S57), surface treatment step (S58), including the particle selection step (S59).

The core forming step (S51) is a step of forming a core by mixing 5 to 20 parts by weight of monomer and 0.1 to 3 parts by weight of a polymerization initiator with respect to 100 parts by weight of the solvent. The core particles are formed by mixing about 15 to 24 hours, including the type and content of the monomer and polymerization initiator as discussed in the charged particles 26. Core particles formed by the core forming step (S10) is as shown in FIG.

Dissolving step (S52) is a step of dissolving tetranol butyl titanate in ethanol (EtOH). This is a step for controlling the reaction rate of tetranomal butyl titanate and silica, and after dissolving tetranomal butyl titanate in ethanol proceeds to the following mixing process.

In the first mixing step (S53), tetraethylorthosilicate is mixed with 0.7 to 5 parts by weight based on 100 parts by weight of the solvent to prepare a first mixed solution.

In addition, the second mixing step (S55) is a step of preparing a second mixture solution by mixing 0.5 to 2 parts by weight of tetranomal butyl titanate with respect to 100 parts by weight of the solvent in the first mixture solution. Tetranomal butyl titanate has an effect of significantly improving the reflectance of the flowable particles.

As shown in FIG. 18, when only tetranomal butyrate is mixed without adding tetraethyl orthosilicate (a), when tetraethyl orthosilicate is mixed first and then tetranomal butyrate is mixed (b), Comparing the case of first mixing tetranomal butyl titanate and then mixing tetraethyl orthosilicate (c) in the SEM picture, in the case of (a) in the case of the reverse reaction is converted into monomers, no particles are formed, In the case of (c), particles cannot be formed because separation is impossible, and thus, fluid particles are normally formed only when tetraethylorthosilicate is mixed as in the present invention (b). This data demonstrates that the mixing order also has an important effect on particle formation.

In addition, Figure 19a is a graph of the size of the core particles through the core forming step (S10), Figure 19b is a particle size graph for Figure 18 (a), Figure 19c is a particle size graph for Figure 18 (b) In addition, it can be seen that (b) of the present invention even more (a) the size of the particles, silica and titanium dioxide is combined without forming a particle.

In the pH adjusting step (S54), in the first mixing step or the second mixing step, an acid or alkali solution is added to the first mixed solution or the second mixed solution to adjust the hydrogen ion index (pH) to 8 to 13. This step is to adjust. As described above, since the polymerization initiator reacts well in a basic environment, a small amount of an acid such as hydrochloric acid and sulfuric acid or an alkaline solution such as ammonia or sodium hydroxide is added to make a basic environment as necessary. It is desirable to make a phosphorus environment. Most preferably it is effective that the pH is 10-11. When the hydrogen ion index (pH) is less than 8 or more than 13, the coupling reaction between the monomer and silica and titanium dioxide (TiO ₂ ) does not occur well, and thus there is a problem in that stable fluid particles cannot be prepared. However, since silica particles are basic, a separate acid or base may not be required.

The polymerization step (S56) is a step of polymerizing the second mixed solution at a temperature of 40 to 90 ° C. for 30 to 50 hours to prepare fluid particles. The polymerization temperature is preferably maintained at a temperature of 40 to 90 ° C, more preferably 60 to 75 ° C. The polymerization step (S50) is to perform the polymerization while stirring, supplying an inert gas such as nitrogen (N ₂ ) or argon (Ar), while removing the dissolved oxygen contained in the solvent, preferably 15 to 24 hours More preferably, the polymerization by the non-emulsification polymerization method is performed for 18 to 22 hours. If the polymerization time is less than 15 hours or more than 24 hours, the polymerization reaction is not smoothly performed, there is a problem that a stable fluid particles can not be produced.

Drying step (S57) is a step of drying the flowable particles. This may be carried out in accordance with the drying step of the conventional method for producing a fluid particle, preferably dry using a supercritical process or atmospheric pressure drying of the wet gel subjected to surface hydrophobization and solvent substitution (for example, normal oven drying), etc. Can be used. In addition, lyophilization can be performed. This may be used after cooling the mixed aqueous solution containing the polymerized polymer to -100 ° C to -10 ° C to solidify the material, and then lowering the pressure to 4.6torr or less to sublimate the water contained in the freeze powder. .

Surface treatment step (S58) is a step of treating the surface of the flowable particles with silane. This is a process of hydrophobizing the surface of the flowable particles in order to prevent agglomeration between particles due to the presence of OH groups at the ends of the prepared flowable particles. As a surface treatment method, the OH group of the fluid particles is removed by causing hydrolysis and condensation reaction using salane.

Here, the silane may be any kind of silane, but tridecafluoro

-1,1,2,2-tetrahydrooctyltriethoxysilane (tridecafluoro-1,1,2,2-tetrahydro

octyltriethoxysilane, CF ₃ -TES) or 3,3,3-trifluoropropyltrimethoxysilane

(3,3,3-trifluoropropryl methoxysilane, CF ₃ -TMS) or ethoxytrimethylsilane

The use of at least one of (ethoxytrimethylsilane, ETMS) is the most effective to suppress the flocculation between the flowable particles after several experiments.

_{<CF 3 -TES><CF 3} -TMS><ETMS>

20 and Table 3 are the results of Experiment 1, FIG. 21 and Table 4 are the results of Experiment 2, and only the weight ratio of silica and tetranomal butyl titanate was changed, and the results of the experiments on the silane treatment were performed. , As shown in Table 4, the silane-treated particles noticeably lower the initial driving voltage than the silane-treated particles, among which the CF ₃ -TES and CF ₃ -TMS treatment was more initial than the ETMS. It can be lowered.

TABLE 3

Initial drive voltage (V) No silane treatment 160 ETMS processing 130 CF ₃ -TES treatment 130

TABLE 4

Initial drive voltage (V) No silane treatment 130 ETMS processing 120 CF ₃ -TES treatment 100 CF ₃ -TMS processing 100

In the surface treatment step (S58), the silane preferably contains 5 to 10 parts by weight, and most preferably 6.5 to 8 parts by weight based on 100 parts by weight of the solvent. If it is less than 5 parts by weight, the effect of preventing aggregation between the fluid particles is insignificant, and if it exceeds 10 parts by weight, there is a problem that the initial driving voltage of the fluid particles is increased.

22 and Table 5 are experimental results of measuring the change in the initial driving voltage according to the content of the silane, as shown in Figure 22 and Table 5, when the silane is included in 100 parts by weight of solvent, 3 parts by weight When the drive voltage 130V, 7 parts by weight is included, it can be seen that the initial drive voltage can be lowered as much as possible by maintaining the content of silane corresponding to the scope of the present invention to the initial drive voltage 110V.

TABLE 5

Initial drive voltage (V) ETMS treatment (3% by weight) 130 ETMS treatment (7% by weight) 110

In addition, in the surface treatment step (S58), the hydrogen ion index (pH) is preferably maintained at 8 to 13, most preferably at 10 to 11 is effective. If the hydrogen ion index (pH) is less than 8 or exceeds 13, there is a problem that the initial drive voltage increases.

23 and Table 6 are experimental results of measuring the change in the initial driving voltage according to the hydrogen ion index (pH), since the effect of the silane treatment varies depending on the hydrogen ion index (pH), the optimal hydrogen ion index (pH) It is an experiment to prove that it should be maintained. As shown in FIG. 23 and Table 5, it can be seen that the initial driving voltage is the lowest when the hydrogen ion index (pH) is maintained at 10, which is the range of the present invention, and silane treatment.

TABLE 6

Initial drive voltage (V) no pH adjustment 130 pH 10 100 pH 2 110

In addition, the particle selection step (S80) is a step of selecting only particles of an appropriate size by passing the manufactured fluid particles through a sieve in which a plurality of holes exist. The hole size of the sieve in the particle stage (S80) is preferably 10 to 30㎛, most preferably 15 to 25㎛. If the size of the hole is less than 10㎛, there is a problem that most of the particles are filtered smaller than the size of the particles, if the size exceeds 30㎛ most of the particles are not filtered, there is a problem that the effect of particle selection.

As shown in FIG. 24 and Table 7, when the sieve is not sifted, when the sieve is hit with a 25 μm sieve, and when the sieve is hit with a 15 μm sieve, the initial driving voltage v is compared. When the sieve was high, the initial driving voltage was measured to be low, and the sieve stage showed excellent flowable particle performance.

<Table 7>

Initial drive voltage (v) If not hit 130 When hit with 25㎛ sieve 80 When hit with a 15㎛ sieve 80

The order of the above steps is not absolute and can be changed in some cases, and it is also within the scope of the present invention.

Filling step (S60) is a step of filling the charged particles in the cell formed by the first partition wall forming step (S20) and the second partition wall forming step (S30). As shown in FIG. 3, the structure of the cell 25 improves the structural shielding of the charged particles compared to the conventional rectangular cell structure, thereby improving the aperture ratio and contrast ratio of the display device while using single particles, and the reaction speed. It also has the effect of improving.

In addition, referring to the charged particles 26 filled in the cell 25, the charged particles 26 is composed of a single particle having the same charging characteristics. In the related art, as shown in FIG. 1, two kinds of charged particles 610 and 620 are charged in positive (+) and negative (-) and have different kinds of colors of black and white, respectively. Particles having different charge characteristics than those of different types are filled, so that collision and agglomeration of particles due to their electrostatic attraction are likely to occur, resulting in a decrease in durability of the device and a slow reaction speed. In order to solve this problem, in the present invention, the charged particles 26 filled in the cell 25 have the same charging characteristics, and by using single particles having only one kind of color such as white, the collision and aggregation of particles are remarkably occurred. Reduction, thereby improving the durability of the device, there is an advantage that the reaction speed is also improved.

Finally, the bonding step (S60), as shown in Figure 3, combines the first partition 23 with the second partition 24, the first partition 23 is dependent on the second partition (24) The upper substrate 20 is positioned between the upper substrate 20 and the lower substrate 28, and the upper substrate 20 is bonded to the lower substrate 28 so that the upper substrate 20 and the lower substrate 28 face each other. The bonding method is to bond the lower substrate 28 and the upper substrate 20 to which the second partition wall 30 formed by the curable composition is attached according to the present invention.

Although the embodiments of the present invention have been described only for a single particle having the same charging characteristics, the present invention can also be implemented using two or more types of charged particles having different charging characteristics of the prior art.

Although preferred embodiments of the present invention have been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

Figure 1a is a cross-sectional view showing a collision charging type electronic paper display device according to the prior art

Figure 1b is a cross-sectional view showing the particles used in the electronic paper image display device according to the prior art

2A to 2D are flowcharts illustrating a process of forming a partition wall using photolithography in an electronic paper display device according to the related art.

3 is a cross-sectional view and a plan view of an electronic paper display device according to an embodiment of the present invention.

4 is a plan view illustrating a first partition of an electronic paper display device according to an embodiment of the present invention.

FIG. 5 is a TEM photograph of particles generated according to whether PVP is added or not.

6 is a graph showing the particle size distribution according to FIG.

7 is a graph in which the particles of FIG. 5 are analyzed by infrared spectroscopy.

8 is a graph measuring the inorganic content according to the temperature of the particles according to FIG.

9 is a TEM photograph of the particles according to the content ratio of tetranomal butyl titanate and tetraethyl orthosilicate

FIG. 10 is a TEM photograph of particles (with PVP) according to the content ratio of tetranomal butyl titanate and tetraethyl orthosilicate

FIG. 11 is a graph showing the conversion rate of tetraolmalbutyl titanate according to the content ratio of tetraethylorthosilicate and tetraolmalbutyl titanate

12 is a graph showing the size distribution of particles according to the content ratio of tetraethylorthosilicate and tetraolmalbutyl titanate

13 is a graph showing the driving voltage (V) according to the content ratio of tetraethylorthosilicate and tetraolmalbutyl titanate

14 is a flowchart sequentially showing a method of manufacturing an electronic paper display device using TEOS fluid particles according to the present invention.

15 is a schematic view of the first partition wall forming step according to the manufacturing method of the electronic paper display device using the TEOS fluid particles of the present invention.

16 is a schematic view of a second partition and protrusion forming step according to a method for manufacturing an electronic paper display device using the TEOS fluid particles of the present invention.

Figure 17 is a TEM photograph taken the core particles formed by the core forming step (S51) of the present invention

FIG. 18 is a TEM photograph of particles produced according to a mixing sequence of tetraethylorthosilicate and tetraolmalbutyl titanate. FIG.

19 is a graph showing the particle size distribution according to FIG. 18.

20 is a graph showing the driving voltage (V) of the particles according to the silane treatment

21 is a graph showing the driving voltage (V) of the particles according to the silane treatment

22 is a graph showing the driving voltage (V) of the particles according to the content of silane

23 is a graph showing the driving voltage (V) of the particles according to the hydrogen ion index (pH) of the silane

24 is a graph showing the driving voltage (V) when sifting fluid particles

<Description of Signs of Major Parts of Drawing>

1: polymer particle 2: charge control agent

3: pigment / dye 4: external additive

10: upper substrate 11: lower substrate

12: upper electrode 13: lower electrode

14: bulkhead 15: (+) charged particles

16: (-) charged particle

20: upper substrate 21a: upper electrode

21b: lower electrode 22: hole

23: first partition 24: second partition

25: cell 26: charged particle

27: projection 28: lower substrate

29a: white display screen 29b: black display screen

30: upper substrate 31a: upper electrode

31b: lower electrode 32: hole

33: first partition 34: second partition

35: cell 36: charged particle

37: projection 38: lower substrate

39a: white display screen 39b: black display screen

40: mold 41: curable composition

42: hole 43: first bulkhead

50: mold 51: curable composition

52: protrusion 53: lower substrate

100: substrate

200: electrode

300: photoresist

400: pattern

500: bulkhead

Claims (13)

An electronic paper display device using a partition wall forming a cell between an upper substrate and a lower substrate disposed to face each other at a predetermined interval, and TEOS fluid particles filled with charged particles in the cell. An electrode formed in contact with at least one of the upper substrate and the lower substrate; A first partition wall including at least one hole and positioned between the upper substrate and the lower substrate and disposed to face the upper substrate and the lower substrate, respectively; A second partition wall that divides pixels between the upper substrate and the lower substrate and connects the upper substrate and the lower substrate; Charged particles filled in a cell formed by the first and second partition walls; The charged particles are based on a solvent and 100 parts by weight of a solvent, 5 to 20 parts by weight of monomer, 0.1 to 3 parts by weight of polymerization initiator, 0.5 to 15 parts by weight of dispersion stabilizer, 0.5 to 2 parts by weight of tetraolmalbutyl titanate, and tetraethylortho. Electronic paper display using TEOS fluid particles, characterized in that it comprises a silica (Tetraethyl Ortho silicate) 0.7 to 5 parts by weight. The method of claim 1, And a protrusion formed on a surface of the lower substrate and disposed to face a hole formed in the first partition wall. The method according to claim 1 or 2, The polymerization initiator is 2,2'-azobis (isobutyramidine) hydrochloride (2,2'-azobis (isobutyramidine) hydrochloride) characterized in that the electronic paper display device using TEOS fluid particles. The method according to claim 1 or 2, The charged particle is a single particle having the same charging characteristics, the electronic paper display device using the TEOS fluid particles, characterized in that the hydrogen ion index (pH) is 8 to 13. The method according to claim 1 or 2, The hole formed in the first partition wall has an electronic paper display device using the TEOS fluid particles, characterized in that the width of the widest portion is 2 to 5㎛, the width of the narrowest portion is 1 to 2㎛. The method according to claim 1 or 2, The inside of the hole formed in the first partition wall is formed so that the diameter becomes narrower toward the center, the cross section of the hole formed in the first partition wall is an electronic paper display device using a TEOS fluid particles, characterized in that the smooth curve shape. In the manufacturing method of the electronic paper display device using a partition wall for forming a cell between the upper substrate and the lower substrate facing each other at a predetermined interval, and TEOS fluid particles filled with charged particles inside the cell, An electrode forming step of forming an electrode on at least one of the upper substrate and the lower substrate; A first partition wall forming step including at least one hole, wherein the first partition wall is formed between the upper substrate and the lower substrate and forms a partition wall disposed on the upper substrate and the lower substrate, respectively; A second partition wall forming step of dividing pixels between the upper substrate and the lower substrate and forming a partition wall connecting the upper substrate and the lower substrate; A projection forming step formed on a surface of the lower substrate and forming a projection disposed to face the hole formed in the first partition wall; A particle forming step of forming the charged particles; A filling step of filling the charged particles into cells formed by the first and second partition walls; And bonding the upper substrate to the lower substrate such that the upper substrate and the lower substrate face each other. 10. The method of claim 7, wherein The first partition wall forming step, An application step of preparing a mold and applying a curable composition on the mold; A curing step of curing the applied curable composition by irradiating ultraviolet rays or by applying heat; And a separation step of separating the curable composition from a mold to form a partition wall. 10. The method according to claim 7 or 8, The second partition wall forming step, An application step of preparing a mold and applying a curable composition on the mold; Positioning the lower substrate such that the applied curable composition and the lower substrate face each other, and then curing the curable composition by irradiating ultraviolet rays or applying heat to the curable composition; And a separation step of separating the cured curable composition and the lower substrate from a mold to form a partition wall. 10. The method according to claim 7 or 8, The particle forming step, A core forming step of forming a core by mixing 5 to 20 parts by weight of a monomer, 0.1 to 3 parts by weight of a polymerization initiator, and 0.5 to 15 parts by weight of a dispersion stabilizer based on a solvent and 100 parts by weight of a solvent; A dissolution step of dissolving tetranomal butyl titanate in ethanol (EtOH); A first mixing step of preparing a first mixed solution by mixing tetraethylorthosilicate in the core with 0.7 to 3 parts by weight based on 100 parts by weight of the solvent; A second mixing step of preparing a second mixed solution by mixing tetraolmalbutyl titanate with 0.5 to 2 parts by weight with respect to 100 parts by weight of the solvent to the first mixed solution; A polymerization step of polymerizing the second mixed solution at a temperature of 40 to 90 ° C. for 30 to 50 hours to produce fluid particles; A drying step of drying the flowable particles; A surface treatment step of treating the surface of the flowable particles with silane; In the first mixing step or the second mixing step, pH adjustment step of adjusting the pH of the hydrogen ion (pH) to 8 to 13 by adding an acid or alkaline solution to the first mixture solution or the second mixture solution; Selecting particles to select particles using a sieve made of a hole of 10 to 30㎛; Electronic paper display device manufacturing method using a TEOS fluid particles comprising a. The method according to claim 7 or 8, In the filling step, the charged particles are a single particle having the same charging characteristics, and a hydrogen ion index (pH) is 8 to 13, characterized in that the electronic paper display device manufacturing method using the TEOS fluid particles. The method according to claim 7 or 8, In the first partition wall forming step, the inside of the hole formed in the first partition wall is formed so that the diameter becomes narrower toward the center, the cross-section of the hole formed in the first partition wall is characterized in that the TEOS flow particles characterized in that the smooth curve shape Method of manufacturing an electronic paper display device using. The method according to claim 7 or 8, In the first partition wall forming step, the hole formed in the first partition wall has the width of the widest portion is 2 to 5㎛, the narrowest portion of the electronic paper using the TEOS fluid particles, characterized in that 1 to 2㎛ Method of manufacturing a display device.

Images