KR20140036599A - Electrophoretic display device and method for manufacturing the same - Google Patents

Abstract

The present invention relates to an electrophoretic display device capable of improving display quality and a manufacturing method thereof capable of improving manufacturing efficiency. The electrophoretic display device according to an embodiment includes pixel electrodes formed on each pixel formed on a bottom substrate, a first separating film formed between the pixel electrodes in a matrix type, a partition overlapped with the first separating film and surrounding the pixels, a charge carrier and solvent in a pixel area formed by the partition, a common electrode formed on a top substrate, a second separating film formed on the top substrate to be matched with the first separating film, and a sealing layer covering the second separating film and the common electrode and a sealing layer attaching the top substrate and the bottom substrate to each other.

Description

Electrophoretic display device and its manufacturing method {ELECTROPHORETIC DISPLAY DEVICE AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to an electrophoretic display device, and more particularly, to a method for manufacturing an electrophoretic display device capable of improving display quality and an electrophoretic display device capable of improving manufacturing efficiency.

An electrophoretic display device refers to an apparatus that displays an image using an electrophoresis phenomenon in which colored charged particles move by an electric field applied from the outside. Here, the electrophoresis phenomenon refers to a phenomenon that the charged particles move in the solvent by the Coulomb force when an electric field is applied to an electrophoretic dispersion (e-ink) in which charged particles are dispersed in a solvent.

The electrophoretic display apparatus using the electrophoretic phenomenon has a feature of bistable, and even if the applied voltage is removed, the original image can be displayed for a long time. That is, the electrophoretic display device is a display device suitable for the field of e-books that do not require a rapid exchange of the screen because it can maintain a constant screen for a long time even without applying a voltage continuously.

In addition, the electrophoretic display device is not only dependent on the viewing angle, but also can provide a comfortable image to the eye to the extent that it is similar to paper. Flexibility, low power consumption and eco-like flexibility are also available.

1 is a view showing an electrophoretic display device according to the prior art.

Referring to FIG. 1, an electrophoretic display device according to the related art includes an electrophoretic film interposed between an oppositely bonded lower substrate 10 and an upper substrate 20, and between the lower substrate 10 and the upper substrate 20. (30).

A plurality of pixels is formed on the lower substrate 10, and a thin film transistor (TFT, not shown) and a pixel electrode (not shown) are formed on the plurality of pixels.

The common substrate 22 is formed on the upper substrate 20 to face the pixel electrode.

The electrophoretic film 30 includes a plurality of microcapsules 32 and an adhesive layer 34.

The plurality of microcapsules 32 are composed of a plurality of charged particles and a solvent. Some of the charged particles are partially charged with positive (+) polarity, and some are charged with negative (-) polarity. For example, the black charged particles may be charged with negative polarity and the white charged particles may be charged with positive polarity.

The adhesive layer 34 protects the microcapsules 32 and adheres the electrophoretic film 30 to the lower substrate 10.

When an electric field is formed between the pixel electrode of the lower substrate 10 and the common electrode 22 of the upper substrate 20, the charged particles included in the microcapsule 32 move by electrophoresis to display an image. .

The electrophoretic display device according to the related art manufactures the lower substrate 10, the upper substrate 20, and the electrophoretic film 30, respectively. The electrophoretic film 30 is stored and transported in an attached state to the upper substrate 20. Thereafter, the release film (not shown) attached to the lower part of the electrophoretic film 30 is removed, and the electrophoretic film 30 is attached to the lower substrate 10 by a lamination process.

Therefore, since the lower substrate 10, the upper substrate 20, and the electrophoretic film 30 must be separately manufactured, the manufacturing process is complicated, and the manufacturing time is long, which results in a low manufacturing efficiency. In addition, since the separately prepared electrophoretic film 30 must be applied, the manufacturing cost increases.

An object of the present invention is to provide an electrophoretic display device capable of improving display quality by increasing a contrast ratio of an image and a method of manufacturing the same.

The present invention is to improve the manufacturing efficiency of the electrophoretic display device.

The present invention provides an electrophoretic display device having improved driving reliability and a method of manufacturing the same.

An object of the present invention is to provide an electrophoretic display device capable of realizing a high quality color image and a method of manufacturing the same.

The present invention is to provide a method of manufacturing an electrophoretic display device that can prevent the unfilled and overfilled electrophoretic dispersion (display solvent).

Other features and advantages of the invention will be set forth in the description which follows, or may be obvious to those skilled in the art from the description and the claims.

Electrophoretic display device according to an embodiment of the present invention for achieving the above object is a pixel electrode formed for each of the plurality of pixels formed on the lower substrate; A first separator formed in a matrix form between the pixel electrodes; Barrier ribs formed on the first separator and overlapping the plurality of pixels; Charged particles and a solvent filled in the pixel region formed by the barrier ribs; A common electrode formed on the upper substrate; A second separator formed on the upper substrate to correspond to the first separator; And a sealing layer formed to cover the common electrode and the second separator to bond the lower substrate and the upper substrate together.

Method of manufacturing an electrophoretic display device according to an embodiment of the present invention for achieving the above object comprises the steps of forming a pixel electrode on the lower substrate; Forming a hydrophobic first separator between the pixel electrodes; Forming a barrier rib to overlap the upper portion of the first separation layer and surround the plurality of pixels; Filling charged particles and a solvent in the pixel region formed by the barrier rib; Forming a common electrode formed on the upper substrate and forming a second separator to correspond to the first separator; Forming a sealing layer to cover the common electrode and the second separator; And bonding the lower substrate and the upper substrate together.

An electrophoretic display device and a method of manufacturing the same according to an embodiment of the present invention can improve display quality by increasing a contrast ratio of an image.

The manufacturing method of the electrophoretic display device according to the embodiment of the present invention can improve the manufacturing efficiency.

The present invention according to the embodiment can provide an electrophoretic display device with improved driving reliability and a manufacturing method thereof.

The present invention according to the embodiment can provide an electrophoretic display device and a method of manufacturing the same that can implement a high quality image in a variety of colors.

The method of manufacturing an electrophoretic display device according to an embodiment of the present invention can prevent the unfilled and overfilled electrophoretic dispersion (display solvent).

The present invention can prevent the electrophoretic dispersion from being overflowed to the upper part of the barrier rib in the manufacturing process for internalizing the electrophoretic dispersion in the lower substrate.

In addition, other features and advantages of the present invention may be newly understood through embodiments of the present invention.

1 is a view showing an electrophoretic display device according to the prior art.
2 is a view showing an electrophoretic display device according to an embodiment of the present invention capable of displaying a black and white image.
3 is a view showing an electrophoretic display device according to an embodiment of the present invention capable of displaying a color image.
4 is a plan view of a lower substrate, in which a first separator is formed on the lower substrate.
FIG. 5 is a plan view of an upper substrate, illustrating a second separator formed on the upper substrate. FIG.
6 to 17 illustrate a method of manufacturing an electrophoretic display device according to an example of the present invention.

Hereinafter, an electrophoretic display device and a method of manufacturing the same according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing an embodiment of the present invention, when it is described that a structure is formed on or above another structure, and below or below it, such a substrate may be formed of any of these structures, To the extent that a third structure is interposed between the first and second structures.

The present invention proposes an electrophoretic display device in which an electrophoretic dispersion (display solvent) including charged particles and a solvent is embedded in a lower substrate, and a method of manufacturing the same. The technical idea of the present invention can be applied to all types of electrophoretic display devices regardless of whether a monochrome image or a color image is displayed.

2 is a view showing an electrophoretic display device according to an embodiment of the present invention capable of displaying a black and white image, Figure 3 is a view showing an electrophoretic display device according to an embodiment of the present invention capable of displaying a color image to be.

2 and 3, an electrophoretic display apparatus according to an exemplary embodiment of the present invention may display an image interposed between a lower substrate 100, an upper substrate 200, and two substrates 100 and 200 to display an image. Includes a phoretic layer.

The lower substrate 100 includes a lower base substrate 110, a pixel electrode 120, a first isolation film 130, and partition walls 140. The electrophoretic dispersion liquid for displaying an image by electrophoresis is filled in the space provided by the partition wall 140. In the present invention, the electrophoretic dispersion is defined as a display solvent.

Although not shown in the figure, a plurality of gate lines (not shown) and a plurality of data lines (not shown) are formed on the lower base substrate 110 so as to intersect with each other. A plurality of pixels are defined by intersection of a plurality of gate lines and a plurality of data lines, and a thin film transistor (TFT) is formed in each of the plurality of pixels. The insulating layer 115 is formed to cover the thin film transistor.

The gate of the thin film transistor is connected to the gate line, the source electrode is connected to the data line, and the drain is electrically connected to the pixel electrode 120. The on-off of each pixel is switched through the thin film transistor, and the data voltage applied to the data line is supplied to the pixel electrode 120. [

The pixel electrode 120 may be formed of a single layer structure of copper, aluminum, indium tin oxide (ITO) or indium zinc oxide (IZO), or nickel or gold in the above-described material of copper, aluminum, ITO, or IZO. Or the like can be formed into a multi-layered structure further laminated.

The pixel electrode 120 is not necessarily transparent because the pixel electrode 120 is located on the opposite side where the image is displayed. For example, the pixel electrode 120 is formed of a transparent conductive material such as ITO or IZO.

The partition wall 140 is formed to surround the pixel electrode 120 formed in each of the plurality of pixel regions to define a space in which the display solvent is filled, that is, a filling space of each cell. At this time, the partition wall 140 is formed to have a height of 10㎛ ~ 100㎛ and a width of 5㎛ ~ 30㎛. The partition wall 140 provides a filling space having a horizontal and vertical length of 50 μm to 150 μm and a height of 10 μm to 100 μm.

The partition wall 140 is formed of a non-polar organic material or a non-polar inorganic material to match the physical properties of the display solvent, so that the display solvent can be smoothly filled during the manufacturing process.

The display solvent is filled in the space provided by the partition wall 140 to form an electrophoretic layer for displaying an image. Here, the display solvent is composed of a plurality of charged particles 150 and the solvent 160.

Some of the plurality of charged particles 150 are charged with a positive (+) polarity, and others are charged with a negative (-) polarity.

When the electrophoretic display device displays a black and white image, as shown in FIG. 2, the plurality of charged particles 150 are colored in a black color and a white color.

At this time, the charged particles of black color may be formed of a carbon black material, and the charged particles of white color may be formed of titanium oxide (TiO ₂ ).

Meanwhile, when the electrophoretic display device displays a color image, as shown in FIG. 3, the plurality of charged particles 150 may be red, green, blue, and black color. Can be colored.

Pixels filled with red and black charged particles display an image of red color, pixels filled with green and black charged particles display an image of green color, and charged particles of blue and black color The filled pixel may display a blue color image. In this way, a full color image can be displayed by combining red, green, and blue colors.

The charged particles 150 are colored in a color corresponding to the color to be displayed by each pixel. Although not shown in the drawing, the charged particles 150 may be colored in colors of yellow, cyan, magenta, and white.

The solvent 160 may be a nonpolar organic material or a nonpolar inorganic material having a viscosity of 10 cP to 10 KcP so that the charged particles 150 may be moved by electrophoresis.

As an example, the solvent 160 may include halogenated solvents, saturated hydrocarbons, silicone oils, low molecular weight halogen-containing polymers, and epoxides. epoxides, vinyl ethers, vinyl esters, aromatic hydrocarbons, toluene, toluene, naphthalene, liquid paraffinic liquids or polychlorotrifluoroethylene polymers (poly chlorotrifluoroethylene polymers) materials may be used.

During the manufacturing process, in the process of filling the display solvent in the lower substrate 100, the display solvent comes into contact with the side surface of the partition wall 140 in the pixel, and thus, the display solvent may not be smoothly filled.

In the present invention, in order to smoothly fill the display solvent in the pixel, the first separation layer 130 is formed under the partition wall 140. The separator 140 separates the pixel electrodes 120 and separates sidewalls of the display solvent and the partition wall 140 during the manufacturing process.

4 is a plan view of a lower substrate, in which a first separator is formed on the lower substrate.

Referring to FIG. 4, the first separator 130 is formed under the partition wall 140 when viewed based on a cross section, and is formed between the pixel electrodes 120 of each pixel when viewed based on a plane. have. The first separation layer 130 is formed to surround the plurality of pixel electrodes 120 similarly to the partition wall 140, and may be formed in a matrix form as illustrated in FIG. 4. The first separation membrane 130 may be formed to have the same width as that of the partition wall 140 or larger than the partition wall 140.

A mask for forming a matrix pattern is disposed on the pixel electrode 120 formed of ITO or IZO material, and then an oxygen gas or a nitrogen gas is deposited to form a first separator 130. . Meanwhile, the first separator 130 may be formed by depositing, doping, or coating a hydrophobic material as well as oxygen or nitrogen gas.

Since the first separator 130 having the hydrophobic property is formed under the partition wall 140, when the display solvent is filled in the pixel, the display solvent may be prevented from adhering to the sidewall of the partition wall 140. .

2 and 3, the upper substrate 200 includes an upper base substrate 210, a common electrode 220, a second separator 230, and a sealing layer 240.

Since the upper substrate 200 is transparent to display an image, the upper base substrate 210 may be formed of transparent glass or transparent plastic.

The common electrode 220 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), and is formed in a plate shape to correspond to all pixels.

During the manufacturing process, during the process of bonding the lower substrate 100 and the upper substrate 200, the display solvent filled in the pixel by the pressure may overflow the neighboring pixels beyond the partition wall 140.

If the display solvent overflows to the upper part of the partition wall 140, the upper part of the partition wall 140 may be contaminated. In addition, in order to display a color image, charged particles of red, green, and blue colors are divided and filled in pixels. If a charged particle of a color other than the color that each pixel is intended to display is introduced, it becomes impossible to display the color image. Problems may arise.

In the present invention, the second separator 230 is formed on the upper substrate 200 in order to prevent contamination of the upper portion of the partition 140 and color defects. The second separator 230 is formed to correspond to the first separator 130 formed on the lower substrate 100, and is formed in a similar or identical pattern to the first separator 130. The second separator 230 separates the upper portion of the partition wall 140 from the display solvent during the manufacturing process to prevent the display solvent filled in the pixel from overflowing to the neighboring pixel.

FIG. 5 is a plan view of the upper substrate, illustrating a second separator formed on the upper substrate.

Referring to FIG. 5, when viewed based on a cross section, the second separator 230 is formed on the upper substrate 200 to be disposed above the partition wall 140. When viewed based on a plane, the first separator 130 and the partition wall 140 formed on the lower substrate 100 are formed in the same or similar matrix form. The second separation membrane 130 may be formed to have the same width as that of the partition wall 140 or larger than the partition wall 140.

A mask for forming a matrix pattern is disposed on the common electrode 220 formed of an ITO or IZO material, and then a second separator 230 is formed by depositing an oxygen gas or a nitrogen gas. . Meanwhile, the second separator 230 may be formed by depositing, doping, or coating a hydrophobic material as well as oxygen or nitrogen gas.

Since the second separator 230 having the hydrophobic property is formed on the partition wall 140, when the lower substrate 100 and the upper substrate 200 are bonded to each other, the display solvent overflows to the upper part of the partition wall 140. It is possible to prevent the occurrence of a phenomenon that contaminates the pixel.

The sealing layer 240 is formed of a transparent sealant on the common electrode 220 and the second separator 230, and seals the display solvent embedded in the lower substrate 100 through the sealing layer 240. In this case, the sealing layer 240 has a function of bonding the lower substrate 100 and the upper substrate 200 as well as the purpose of sealing the display solvent.

Hereinafter, a method of manufacturing an electrophoretic display device will be described with reference to FIGS. 6 to 17. 6 to 17 are views illustrating a method of manufacturing an electrophoretic display device according to an example of the present invention.

Referring to FIG. 6, a thin film transistor TFT including a gate, an active source, a source, and a drain is formed on the lower base substrate 110.

The gate of the thin film transistor is connected to the gate line, the source is connected to the data line, and the drain is electrically connected to the pixel electrode 120. And the on-off of the pixel is switched through the thin film transistor. When the scan pulse is applied to the gate of the thin film transistor through the gate line, the thin film transistor is turned on, and the data voltage applied to the data line is supplied to the pixel electrode 120.

Here, the lower base substrate 110 may be a transparent glass substrate, a plastic substrate having flexibility, or a metal substrate. Since the lower substrate 100 of the electrophoretic display device is located on the opposite side of the screen on which the image is displayed, the lower base substrate 110 does not necessarily need to be transparent.

Subsequently, referring to FIG. 7A, an insulating layer 115 is formed to cover the thin film transistor TFT.

Thereafter, the pixel electrode 120 is formed of a conductive material such as copper, aluminum, ITO, or IZO on the insulating layer. In this case, the pixel electrode 120 is formed of a conductive layer of copper, aluminum, ITO or IZO, and after applying the photoresist 124 on the conductive layer 122, the photo using the photoresist 124 as a mask The conductive layer 122 may be patterned by lithography and photolithography. The pixel electrode 120 may be formed for each pixel.

Subsequently, referring to FIG. 7B, a mask for forming a pattern in a matrix form is disposed on the pixel electrode 120 formed of ITO or IZO material, and then oxygen or nitrogen gas is used. Deposition is performed to form the first separator 130. Meanwhile, the first separator 130 may be formed by depositing, doping, or coating a hydrophobic material as well as oxygen or nitrogen gas.

The first separator 130 is formed under the partition wall 140 when viewed based on a cross section, and is formed between the pixel electrodes 120 of each pixel when viewed based on a plane. As shown in FIG. 7C, the first separation layer 130 is formed to surround the plurality of pixel electrodes 120 and may be formed in a matrix form. The first separation membrane 130 may be formed to have the same width as that of the partition wall 140 or larger than the partition wall 140.

When the display solvent is filled in the pixel by forming the first separation layer 130 having the hydrophobic property, it is possible to prevent the display solvent from sticking to the sidewall of the partition wall 140.

Subsequently, referring to FIG. 8, an organic material or an inorganic material is coated on the lower base substrate 110 on which the pixel electrode 120 is formed, and then patterned to form the partition wall 140. In this case, the partition wall 140 is formed to overlap the first separator 130, and is formed in a matrix similar or identical to the first separator 130.

Here, the partition wall 140 may be formed using not only the above-described photolithography method but also an imprinting or mold printing method.

A pixel region (filling space) in which the display solvent is filled through the partition 140 is defined. The partition wall 140 is formed to have a height of 10 μm to 100 μm and a width of 5 μm to 30 μm, and a space having a horizontal and vertical length of 50 μm to 150 μm is provided by the partition wall 140.

The partition wall 140 may contact the display solvent filled in the pixel region through a subsequent manufacturing process. Therefore, the partition wall 140 is formed of a non-polar organic material to match the physical properties of the display solvent so that the display solvent can be filled smoothly. Meanwhile, as another embodiment of the present invention, the partition wall 140 may be formed of a nonpolar inorganic material.

Next, a method of filling the display solvent into each pixel area defined by the partition wall 140 will be described. First, referring to FIGS. 9 and 10, a method of filling a display solvent for displaying a black and white image in a pixel area will be described. Next, referring to Figs. 11 to 14, a method for filling a display solvent for displaying a color image into a pixel area will be described.

Referring to FIG. 9, a display solvent composed of charged particles 150 and a solvent 160 is filled in each pixel region defined by the partition wall 140.

Specifically, after the mask 300 having the opening 310 for opening the pixel region is aligned on the partition wall 140, the charged particles 150 and the filling solvent are screen-printed using the squeegee bar 400. 160) is configured to fill the display solvent.

For example, the mask 300 may include a metal mask made of nickel, an organic mask made of the same material as the partition wall 140, or an inorganic mask. As another example, a mesh mask may be used as the mask 300. The mask 300 may have a thickness of 20 μm to 40 μm, and a hole size of the opening may be 30 μm to 70 μm.

Herein, the solvent 160 may be a nonpolar organic material or a nonpolar inorganic material. The solvent 160 may be a nonpolar inorganic material or a nonpolar organic material having a viscosity characteristic of 10cP ~ 10KcP.

The filling process of the display solvent composed of the charged particles 150 and the solvent 160 may be performed with a squeegee speed of 5 to 50 [mm / sec] and 0.1 to 30 [Kgf / cm 2] squeegee pressure.

The charged particles of black color may be formed of a carbon black material, and the charged particles of white color may be formed of titanium dioxide (TiO ₂ ). Some of the plurality of charged particles 150 are charged with a positive (+) polarity, and others are charged with a negative (-) polarity.

As an example, when the charged particles of black color are charged with a positive polarity, charged particles of white color can be charged with a negative polarity. As another example, when the charged particles of black color are charged with a negative (-) polarity, the charged particles of white color can be charged with a positive (+) polarity.

Solvent 160 includes halogenated solvents, saturated hydrocarbons, silicone oils, low molecular weight halogen-containing polymers, epoxides, vinyl Vinyl ethers, vinyl esters, aromatic hydrocarbons, toluene, naphthalene, liquid paraffinic or poly chlorotrifluoroethylene polymers This can be used.

In addition to the slit coating method, the filling process of the display solvent is not only a screen printing method, a die coating method, a casting method, a bar coating method, and a dispensing The method, the squeezing method, or the inkjet printing method may be used.

Here, the process of filling the display solvent in the pixel area may be performed by dividing a number of times. The more charged particles are filled in the pixel area, the higher the reflection and absorptivity of the light incident from the outside, thereby increasing the contrast ratio and the display quality of the image. In order to increase the contrast ratio of the electrophoretic display device, the charged particles 150 should be filled at least 20% of the pixel area. However, when the charged particles 150 are charged in a single filling process, the amount of charged particles 150 is precisely filled. Can not be adjusted.

By adjusting the filling amount of the charged particles 150, it is possible to increase the opening size of the opening of the mask during the manufacturing process, increase the squeegee pressure, or increase the distance between the mask and the lower base substrate 110. .

However, even with this method, there is a limit to increase the filling amount of the charged particles 150 to 20% or more, and there is a problem in that the display solvent overflows to the upper part of the partition wall 140 during the filling process so that contamination occurs. In order to solve this problem and to increase the amount of charged particles in the pixel region, the charged particles 160 may be divided into multiple times and filled in the pixel region.

For example, during the primary filling process, the charged particles 150 of the display solvent are filled in an amount corresponding to 8% to 14% of the pixel area (filling space) by volume.

Thereafter, in the secondary filling process, the charged particles 150 of the display solvent may be filled in an amount corresponding to a volume in 10% to 50% of the pixel area.

As such, the filling process is divided into several times to uniformly fill the display solvent in the entire pixel area, increase the amount of charged particles 150 to increase the reflection and absorption of external light, thereby increasing the contrast ratio of the image. Can be.

In accordance with the filling method of the display solvent, in consideration of the reactivity of the charged particles 150, a material having no dissolution and precipitation as the solvent 160 may include a dispersant for driving the charged particles 150.

Next, referring to FIG. 10, the solvent 160 is filled to 80% to 100% of the volume of the pixel region. As such, the solvent 160 is filled in the pixel region so that the charged particles 150 are driven by electrophoresis. The solvent 160 may be simultaneously filled in the entire pixel region, thereby filling the display solvent in a uniform amount in the entire pixel region.

On the other hand, although not shown in the drawing, after the process of filling the display solvent described with reference to Figure 9, after drying the solvent filled in the pixel, as shown in Figure 10 the solvent 160 is filled in all the pixels You can.

Next, referring to Figs. 11 to 14, a method for filling a display solvent for displaying a color image into a pixel area will be described.

When the plurality of charged particles 150 are colored in red, green, blue, and black colors, the filling of the display solvent composed of the charged particles 150 and the solvent 160 is charged. The particles 150 may be sequentially formed for each color. That is, the charging of the charged particles 150 and the solvent 160 of red, green, and blue colors may be sequentially performed for each color to be displayed by each pixel.

Referring to FIG. 11, the first mask 510 having an opening for opening only red pixels among all the pixels is aligned on the partition wall 140. Subsequently, the display solvent including the charging particles 150 and the filling solvent 160 of red and black colors is filled in the entire red pixel area by screen printing using the squeegee bar 400.

Next, referring to FIG. 12, the second mask 520 having an opening for opening only the green pixels among all the pixels is aligned on the partition wall 140. Subsequently, the display solvent including green and black charged particles 150 and the filling solvent 160 is filled in the entire green pixel area by screen printing using the squeegee bar 400.

Subsequently, referring to FIG. 13, the third mask 530 having an opening for opening only the blue pixels among all the pixels is aligned on the partition wall 140. Subsequently, the display solvent including the charged particles 150 and the filling solvent 160 of blue and black colors is filled in the entire blue pixel area by screen printing using the squeegee bar 400.

Here, the thicknesses of the first mask 510 to the third mask 530 may be 20 μm to 40 μm, and the hole size of the opening may be 30 μm to 70 μm.

As the first mask 510 to the third mask 530, a metal mask made of nickel, an organic mask made of the same material as the barrier 140, or an inorganic mask may be used. As another example, a mesh mask may be used as the first mask 510 to the third mask 530.

Filling process of the display solvent may be made of a squeegee speed of 5 ~ 50 [mm / sec] and 0.1 ~ 30 [Kgf / ㎠] squeegee pressure. The solvent 160 may be the same materials as the above-described embodiment.

Meanwhile, in addition to the screen printing method, the filling process of the display solvent may include a die coating method, a casting method, a bar coating method, a slit coating method, a dispensing method, and a spray method. A squeezing method, a method, or an inkjet printing method may also be used.

The present invention may divide the charged particles 160 several times and fill the pixel region in order to increase the amount of charged particles in the pixel region.

For example, in the first filling process, the charged particles 150 of the red, green, blue, and black colors of the display solvent are filled in an amount corresponding to 8% to 14% of the pixel area (fill space) by volume.

Thereafter, during the secondary filling process, the charged particles 150 of the red, green, blue, and black colors of the display solvent may be filled in an amount corresponding to a volume in 10% to 50% of the pixel area.

As such, the filling process is divided into several times to uniformly fill the display solvent in the entire pixel area, increase the amount of charged particles 150 to increase the reflection and absorption of external light, thereby increasing the contrast ratio of the image. Can be.

In accordance with the filling method of the display solvent, in consideration of the reactivity of the charged particles 150, a material having no dissolution and precipitation as the solvent 160 may include a dispersant for driving the charged particles 150.

Next, referring to FIG. 14, the solvent 160 is filled to 80% to 100% of the volume of the pixel region. As such, the solvent 160 is filled in the pixel region so that the charged particles 150 are driven by electrophoresis. The solvent 160 may be simultaneously filled in the entire pixel region, thereby filling the display solvent in a uniform amount in the entire pixel region.

On the other hand, although not shown in the drawings, after the process of filling the display solvent described with reference to Figures 11 to 13, and after drying the solvent filled in the pixel as shown in Figure 14 (B) solvent 160 ) Can be filled in all the pixels.

In the above process, since the charged particles 150 are already filled in the red, green, and blue pixel regions, the solvent 160 may be simultaneously filled in the entire pixel region.

Here, the solvent 160 may include halogenated solvents, saturated hydrocarbons, silicone oils, low molecular weight halogen-containing polymers, and epoxides. , Vinyl ethers, vinyl esters, aromatic hydrocarbons, toluene, naphthalene, paraffinic liquids or poly chlorotrifluoroethylene polymers ) Materials can be used.

The solvent 160 is a die coating method, casting method, bar coating method, slit coating method, dispensing method, squeezing method, screen printing method. Each pixel area may be filled by a screen printing method and an inkjet printing method.

In the above description, the charged particles 150 have been described as an example of being colored in red, green, blue, and black colors. However, the present invention is not limited thereto, and the above-described manufacturing method may be equally applied even when the charged particles are colored in yellow, cyan, magenta, and white colors.

Next, referring to FIG. 15, the upper substrate 200 is manufactured by forming the common electrode 220, the second separator 230, and the sealing layer 240 on the upper base substrate 210. At this time, the upper substrate 200 is manufactured separately from the manufacturing process of the lower substrate 100, and may be prepared in advance through a preceding manufacturing process.

Specifically, referring to FIG. 15A, the common electrode 220 is formed by depositing a transparent conductive material such as ITO or IZO on the upper base substrate 210.

Subsequently, referring to FIG. 15B, a mask for forming a pattern in a matrix form is disposed on the common electrode 220 formed of ITO or IZO material, and then oxygen or nitrogen gas is used. Deposition is performed to form a second separator 230. Meanwhile, the second separator 230 may be formed by depositing, doping, or coating a hydrophobic material as well as oxygen or nitrogen gas.

Thereafter, the second separator 230 is formed, and the sealing layer 240 is formed to cover the common electrode 220 and the separator 240.

Meanwhile, the sealing layer 240 may be manufactured in a film type, and then the upper substrate 100 and the lower substrate 200 may be bonded using a lamination process. As described above, the lower substrate 100 and the upper substrate 200 are bonded to each other using the sealing layer 240, so that the shielding of the display area may be completely performed.

Referring to FIG. 15B, the second separator 230 is formed to overlap the upper portion of the partition wall 140 when viewed based on a cross section.

Referring to FIG. 15C, when viewed with respect to a plane, a second separation layer 230 is formed in a matrix so as to surround a plurality of pixels on the partition wall 140. In this case, the second separation membrane 230 may be formed to have the same width as that of the partition wall 240 or a larger width than the partition wall 240.

The second separation layer 130 having the hydrophobic property may be formed to prevent the display solvent filled in the pixel from overflowing to neighboring pixels, thereby preventing the charged particles 150 from being mixed.

16 and 17, the lower substrate 100 filled with the charged particles 150 and the solvent 160 in the entire pixel area is bonded to the upper substrate 200.

The joining of the upper substrate 200 and the lower substrate 100 may be performed through a pressurizing process to apply a predetermined pressure and an annealing process to apply a constant temperature together with the pressing process.

The upper and display solvents of the partition wall 140 are sealed using the sealing layer 240 formed on the upper substrate 200, and the upper substrate 200 and the lower substrate 100 are bonded to each other.

Here, the sealing layer 240 may be formed by applying an adhesive material on the common electrode 220 and the second separation layer 230, followed by an imprinting or photolithography process. As another example, the sealing layer 240 may be formed using a roll-to-roll process using a roller in which a specific pattern is embossed or engraved.

As shown in FIG. 3 by performing the above-described manufacturing process, the electrophoretic display device in which the charged particles 150 and the solvent 160 of red, green, blue and black colors are embedded in the lower substrate 100. Can be prepared.

In the electrophoretic display device manufactured according to the present invention, charged particles of a display solvent filled in a pixel region by an electric field formed by a data voltage applied to the plurality of pixel electrodes 120 and a common voltage applied to the common electrode 220. 150 may move in solvent 160 to display black and white and color images. In addition, a defect in which the electrophoretic display device is contaminated can be prevented, and mass production and reliability of the electrophoretic display device can be improved.

The manufacturing method of the electrophoretic display device according to the embodiment of the present invention described above can prevent the unfilled and overfilled of the display solvent to improve the display quality of the electrophoretic display device and secure driving reliability. In addition, it is possible to improve the mass production and manufacturing efficiency of the electrophoretic display device by preventing the defect due to the unfilled and overfilled display solvent.

The manufacturing method of the electrophoretic display device according to the embodiments of the present invention described above has an advantage that the manufacturing infrastructure (infra) used in the existing manufacturing process of the liquid crystal display device can be applied.

It will be understood by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: lower substrate 110: lower base substrate
120: pixel electrode 130: first separator
140: bulkhead 150: charged particles
160 solvent 200 upper substrate
210: upper base substrate 220: common electrode
230: second separator 240: sealing layer
300: mask 310: hole
400: squeegee bar 510, 520, 530: mask

Claims (10)

Pixel electrodes formed on a plurality of pixels defined on the lower substrate;
A first separator formed in a matrix form between the pixel electrodes;
A partition wall overlapping an upper portion of the first separation layer and surrounding the plurality of pixels;
Charged particles and a solvent filled in the pixel region formed by the barrier ribs;
A common electrode formed on the upper substrate;
A second separator formed on the upper substrate to correspond to the first separator; And
And a sealing layer formed to cover the common electrode and the second separator to bond the lower substrate and the upper substrate together. The method according to claim 1,
And the first separator and the second separator are hydrophobic. The method according to claim 1,
The first separator is formed in a matrix form to surround the plurality of pixels to separate the pixel electrodes. The method according to claim 1,
And the second separator overlaps an upper portion of the partition wall and is formed in a matrix form. The method according to claim 1,
And the first separator and the second separator are formed to have the same width as the width of the barrier rib or larger than the barrier rib. The method according to claim 1,
Wherein the plurality of pixels include:
A red pixel filled with red charged particles and black charged particles,
A green pixel filled with charged particles of green color and charged particles of black color,
An electrophoretic display device comprising a blue pixel filled with charged particles of blue color and charged particles of black color. Forming pixel electrodes on the lower substrate;
Forming a hydrophobic first separator between the pixel electrodes;
Forming a barrier rib to overlap the upper portion of the first separation layer and surround the plurality of pixels;
Filling charged particles and a solvent in the pixel region formed by the barrier rib;
Forming a common electrode formed on the upper substrate and forming a second separator to correspond to the first separator;
Forming a sealing layer to cover the common electrode and the second separator; And
And bonding the lower substrate and the upper substrate to each other. The method of claim 7, wherein
In the forming of the first separator,
And arranging a mask for forming a pattern in a matrix form on the pixel electrode, and then depositing oxygen gas or nitrogen gas to form the first separator. The method of claim 7, wherein
In the forming of the second separator,
And arranging a mask for forming a pattern in a matrix form on the common electrode, and then depositing oxygen gas or nitrogen gas to form the second separator. The method of claim 7, wherein
In the filling of the charged particles and the solvent in the pixel region,
Filling red and black charged particles and a solvent inside the red pixels for displaying a red image,
Charging charged particles and a solvent of green color and black color inside the green pixels for displaying a green image,
A method of manufacturing an electrophoretic display device, comprising charging charged particles and a solvent of blue color and black color inside blue pixels for displaying a blue image.

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