JP2000352945A - Display device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device which is capable of reducing a display unevenness and reducing the production cost, and a process for producing the same. SOLUTION: A insulative liquid 1 and colored electrostatic charge particles 2 which are moved toward first electrode 8 and a second electrode 7 by the voltage impressed to the first electrode 8 and the second electrode 7 are packed into tubes 3 having light transmissibility. Projecting parts 3a which prohibit the movement of the colored electrostatic charge particles 2 are longitudinally regularly formed on the inside wall surfaces of these tubes 3, by which the colored electrostatic charge particles 2 are moves within the range segmented by the adjacent two projecting parts 3a. Further, the tubes packed with the insulative liquid 1 and the colored electrostatic charge particles 2 are arranged in tight contact between a first substrate 4 formed with the first electrode 8 and a light transmissible second substrate 6 on which the second electrodes 7 are formed, thereby, the colored electrostatic charge particles 2 are uniformly dispersed. Also, the colored electrostatic charge particles are moved in a direction perpendicular to the substrates 4 and 6 by the voltage impressed to the first electrode 8 and the second electrode 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device and a method for manufacturing the same, and more particularly, to an electrophoretic display device which performs display by moving charged particles in a liquid by a voltage applied to an electrode.

[0002]

2. Description of the Related Art In recent years, with the development of information equipment, needs for low power consumption and thin display devices have been increasing, and research and development of display devices meeting these needs have been actively conducted. Among them, the liquid crystal display device can change the optical characteristics of the liquid crystal by electrically controlling the arrangement of the liquid crystal molecules, and is actively developed and commercialized as a display device capable of meeting the above needs. ing.

However, in this liquid crystal display device, it is difficult to see characters on the screen due to the angle at which the screen is viewed and reflected light,
The burden on vision caused by flickering and low brightness of the light source has not been sufficiently solved. For this reason, research on a display device with a small burden on vision has been actively studied.

[0004] In view of such low power consumption and reduced burden on the eyes, a reflection type display device is expected.
An electrophoretic display device is known as one of them. Here, the electrophoretic display device includes a dispersion layer composed of charged electrophoretic particles 31 and an insulating liquid 32 as shown in FIG.
A pair of electrodes 33 and 34 facing each other with the dispersion layer interposed therebetween is provided. By applying a voltage to the dispersion layer through the electrodes 33 and 34, the migrating particles 31 are opposite to the electric charges of the particles themselves. I try to draw to the side.

The electrophoretic display device can perform color display by coloring the electrophoretic particles 31 and dyeing the insulating liquid 32. That is, as shown in (b) of the figure, when the colored migrating particles 31 which are colored charged particles adhere to the surface of the first electrode 33 close to the observer, the color of the migrating particles 31 is displayed, and the color of the migrating particles 31 is displayed. As shown in (a), when the ink adheres to the second electrode surface 34 far from the observer, the color of the stained insulating liquid 32 is displayed.

By the way, in the electrophoretic display device having such a configuration, when the electrophoretic display device is used repeatedly for a long time, the electrophoretic particles
There is a possibility that a bias occurs in the density distribution of No. 1, resulting in display unevenness. Therefore, as a method for preventing such a bias in the concentration distribution, for example, as proposed in Japanese Patent Application Laid-Open No. 59-34518 or Japanese Patent Application Laid-Open No. 2-284124, partition walls are provided at regular intervals in the sealing portion. There is a method of forming and dividing into small sections.

Further, as disclosed in Japanese Patent Application Laid-Open No. 1-114828, for example, a porous system composed of a member which swells with a dispersion medium is used, and after the dispersion system is injected, it is divided into discontinuous small sections. There is a way. Here, in this proposal, a plurality of light-transmissive tubes pre-filled with liquid and migrating particles are arranged between the substrates. Since the tubes themselves can serve as partitions, it is unnecessary to form partitions.

As a display device having a structure in which a light-transmitting tube is arranged between substrates, there is a liquid crystal display device proposed in Japanese Patent Application Laid-Open No. 49-96694. This has been proposed as a display device having a configuration in which tubes filled with a liquid crystal material are arranged in parallel, having a uniform thickness, and capable of preventing entry of moisture, gas, and the like from the outside.

[0009]

However, in such a conventional electrophoretic display device, as described above, in order to prevent display unevenness due to the uneven distribution of the concentration of the migrating particles, a partition is formed in the enclosing portion. In this method, the electrophoretic particles must be evenly distributed to each of the small compartments, and the distribution is difficult. In addition, there is a problem that a lot of time and cost are required for a series of manufacturing steps which require formation of partition walls on the substrate, uniform distribution of the electrophoretic particles and the insulating liquid, and sealing.

Further, in the case of performing color display, since electrophoretic particles or insulating liquids of a plurality of colors are used, even when divided into small sections by partition walls, mixing tends to occur in adjacent sections at the time of manufacturing, and a desired color is obtained. It was difficult to fill only the electrophoretic particles of color or the insulating liquid. Therefore,
There is a problem that color display is more difficult.

The present invention has been made in view of such circumstances, and provides an (electrophoretic) display device capable of reducing display unevenness and reducing manufacturing costs, and a method of manufacturing the same. The purpose is to do so.

[0012]

The present invention comprises colored charged particles dispersed in an insulating liquid, and a first electrode and a second electrode for applying a voltage to the colored charged particles. A display device for performing display by moving the colored charged particles in the direction of the first electrode or the second electrode by a voltage applied to an electrode and a second electrode, wherein light is transmitted through the insulating liquid and the colored charged particles. While filling the tube having the property, a convex portion for preventing the colored charged particles from moving in the tube longitudinal direction is regularly formed on the inner wall surface of the tube in the longitudinal direction of the tube, and the tube is formed in the first direction. A first substrate on which one electrode is formed;
A plurality of the electrodes are arranged in close contact with the second substrate on which the electrodes are formed.

[0013] Also, in the present invention, the colored charged particles may define a range defined by two adjacent projections in the tube by the voltages applied to the first and second electrodes. It is characterized by moving in a direction perpendicular to the second substrate.

Further, the present invention is characterized in that the protrusion is formed on an inner wall surface of the tube at least in a direction perpendicular to the first and second substrates.

Further, the present invention is characterized in that the convex portion of the tube is formed by heating and shrinking the tube.

Further, the present invention is characterized in that the convex portion of the tube is formed by press-molding the tube.

Further, the present invention is characterized in that the convex portion of the tube is formed by pressing the tube by a convex structure formed on at least one side of the outside of the tube.

Further, the present invention is characterized in that the tube is made of a polymer.

The present invention also provides a method in which the insulating liquid is colored in a different color from the colored charged particles, and a tube filled with the different colored insulating liquid is provided between the first substrate and the second substrate. It is characterized by being arranged regularly.

Further, the present invention is characterized in that tubes filled with the colored charged particles of different colors are regularly arranged between the first substrate and the second substrate.

Further, the present invention is characterized in that at least one of the first substrate and the second substrate has a light transmitting property.

Further, the present invention is characterized in that the first substrate and the second substrate are polymer films.

Further, according to the present invention, the first electrode and the second electrode
At least one of the electrodes has light transmittance.

Further, the present invention is characterized in that a color display is performed by using any one of the color of the colored charged particles and the color of the insulating liquid.

Further, the present invention comprises colored charged particles dispersed in an insulating liquid, and first and second electrodes for applying a voltage to the colored charged particles, wherein the first and second electrodes are provided. A method for manufacturing a display device in which the colored charged particles are moved in the direction of the first electrode or the second electrode by a voltage applied to the display device to perform display, wherein the insulating liquid and the colored charged particles are light-transmitting tubes. And a step of regularly forming in the longitudinal direction convex portions for preventing the movement of the colored charged particles on the inner wall surface of the tube, and forming the tubes filled with the insulating liquid and the colored charged particles into each other. And placing the first electrode on which the first electrode is formed and the light-transmitting second substrate on which the light-transmitting second electrode is formed in close contact therewith. It is.

Further, the present invention is characterized in that the convex portion of the tube is formed by heating and shrinking the tube before filling the insulating liquid and the charged particles. .

Further, the present invention is characterized in that the convex portion of the tube is formed by press-molding the tube before or after filling the insulating liquid and the colored charged particles. Things.

Further, according to the present invention, the convex portion of the tube may be filled with the insulating liquid and the charged particles, and then the tube may be connected to the first tube.
When the tube is disposed in close contact with the second substrate, the tube is formed by pressing the tube by a convex structure formed on at least one side of the outside of the tube.

Further, as in the present invention, the insulating liquid and the first
The tube is filled with light-transmissive colored particles that move in the direction of the first electrode or the second electrode by the voltage applied to the electrode and the second electrode, and the colored charged particles move on the inner wall surface of the tube. Is formed regularly in the longitudinal direction, so that the colored charged particles are moved within a range defined by two adjacent convex portions. Further, the tubes filled with the insulating liquid and the colored charged particles are placed between the first substrate on which the first electrode is formed and the light-transmissive second substrate on which the light-transmissive second electrode is formed. In this case, the colored charged particles are uniformly dispersed, and are moved in a direction perpendicular to the substrate by a voltage applied to the first electrode and the second electrode.

[0030]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view of an electrophoretic display device as a display device according to an embodiment of the present invention, and FIG. 2 is a diagram showing a part of a cross section thereof.

1 and 2, reference numeral 1 denotes an insulating liquid;
2 is a colored charged particle, 3 is a light-transmitting tube enclosing the insulating liquid 1 and the colored charged particle 2, 4 is a first substrate,
Reference numeral 6 denotes a light-transmitting second substrate, and the tube 3 is held between the first substrate 4 and the second substrate 6. In addition, a first electrode 8 is formed on the first substrate 4, and a light-transmissive second electrode 7 is formed on the second substrate 6.

In this electrophoretic display device (hereinafter referred to as a display device), colored charged particles 2, which are electrophoretic particles charged in an insulating liquid 1, are perpendicular to a substrate surface on a first electrode side or a second electrode side. The display is performed by moving the colored charged particles 2 in the insulating liquid to the first electrode 8 by applying a voltage to the first electrode 8 as shown in FIG.
When collected on the electrodes, the observer (second substrate side) observes (displays) the colored charged particles 2 and the second electrode 7. On the other hand, when the colored charged particles 2 are collected on the second electrode by changing the polarity of the voltage as shown in FIG. 2B, the color of the colored charged particles 2 is observed.

[0034] Then, with this configuration,
For example, if the colored charged particles 2 are black and the insulating liquid 1 is white, black and white display is possible. As will be described later, color display is possible by appropriately disposing the colored charged particles 2 of different colors or the tube 3 in which the colored insulating liquid 1 is sealed.

On the inner wall surface of the tube 3, as shown in FIGS. 1 and 2 and FIG. 3, which is a sectional view of the display device in the longitudinal direction of the tube, convex portions 3a partitioning the tube 3 are regularly arranged in the longitudinal direction. By forming such a convex portion 3a on the inner wall surface of the tube 3, the moving range of the colored charged particles 2 repeatedly moving in the insulating liquid 1 in the direction perpendicular to the substrates 4 and 6 is formed. Can be limited to a space range (hereinafter, referred to as a moving space S) divided by two adjacent protrusions 3a.

By limiting the moving range of the colored charged particles 2 in the moving space S in this way, the colored charged particles 2 can be uniformly arranged at the time of manufacture, and the colored charged particles 2 can be used for a long time. 2 can be reduced. Further, thereby, display unevenness can be reduced.

In this embodiment, the convex portion 3a is formed over the entire inner wall surface of the tube 3. However, if the movement of the colored charged particles 2 can be restricted, the convex portion 3a is Parts, for example, only on the inner wall surface in the direction perpendicular to the substrates 4 and 6. In addition, the moving space S may be completely sealed by two adjacent convex portions 3a so as to restrict the movement of the insulating liquid 1 as well as the colored charged particles 2.

Incidentally, the convex portion 3a may be formed on the inner wall surface of the tube 3 before the colored charged particles 2 and the insulating liquid 1 are filled therein, or the colored charged particles 2 and the insulating liquid 1 may be formed.
May be formed after filling.

Here, the colored charged particles 2 and the insulating liquid 1
In the case where the convex portion 3a is formed before the filling is performed, the convex portion 3a is formed by periodically deforming the tube 3 by, for example, contracting the tube 3 by heating or light irradiation, press molding with a jig, or the like. The pipe 3
The diameter and the pitch and size of the periodically formed protrusions 3a are appropriately determined according to the size of the display pixel.

When the convex portions 3a are formed after the charged charged particles 2 and the insulating liquid 1 are filled, for example, the tube 3 filled with the charged charged particles 2 and the insulating liquid 1 is replaced with a previously formed convex structure. Formed by pressing. Here, the convex structure for forming the convex portion 3a is formed on one side of the outer wall surface of the tube 3,
Alternatively, it can be formed on the upper and lower substrates or a part of the upper and lower electrodes, and the convex portion 3a can be formed by a combination of these convex structures. Further, a method such as press molding using a jig or physical twisting is also possible.

By the way, in such a display device, color display can be performed by using the insulating liquids 1 of plural colors and by using the colored charged particles 2 of plural colors.

Next, a configuration for performing such a color display will be described.

FIG. 4 is a cross-sectional view of a display device for performing color display using a plurality of colors of insulating liquid. In this display device, as shown in FIG. , Magenta (M), and cyan (C) insulating liquids 10, 11, and 12 of each color are regularly arranged. Further, the colored charged particles 2 are made white and the second substrate 6 and the second electrode 7 are formed of a light transmissive material, while the display is observed from the second substrate side.

Here, for example, the display of yellow (Y) is as follows.
The colored charged particles 2 in the tube in which the yellow (Y) insulating liquid 10 is sealed are collected on the first electrode, and the other magenta (M) and cyan (C) insulating liquids 11 and 12 in the tube are sealed. It becomes possible by collecting the colored charged particles 2 on the second electrode. In addition, as shown in the figure, an insulating liquid 1 of yellow (Y), magenta (M), and cyan (C) is used.
If all the colored charged particles 2 in each tube in which 0, 11, and 12 are sealed are collected on the first electrode, black can be displayed. Conversely, all the colored charged particles 2 can be collected on the second electrode. White can be displayed.

On the other hand, FIG. 5 is a sectional view of a display device for performing color display using colored charged particles of a plurality of colors. In this display device, as shown in FIG. The tubes 3 in which the charged particles 13, 14 and 15 of the respective colors (Y), magenta (M) and cyan (C) are sealed are regularly arranged. The display is observed from the second substrate side.

Here, for example, the display of yellow (Y) is as follows.
The yellow (Y) colored charged particles 13 are collected on the second electrode, and the magenta (M) and cyan (C) colored charged particles 1 are collected.
This is made possible by collecting 4,15 on the first electrode.
In addition, as shown in FIG.
If all 5 are collected on the first electrode, white can be displayed. Conversely, if all the charged colored particles 13, 14, 15 are collected on the second electrode, black can be displayed.

In the above-described color display, the colors of the colored charged particles 2, 13, 14, and 15 may be the colors of the materials themselves, or may be those obtained by laminating and mixing other materials on the surface of those materials. Also, the colored charged particles 2, 13, 14, 15
May be composed of one kind or two or more kinds of materials. Further, here, the color display is set to three colors of yellow (Y), magenta (M), and cyan (C). However, depending on the display environment and the displayed image, there is no particular limitation on these.
If necessary, an arbitrary color or a color display using ultraviolet light or infrared light is also possible.

Next, a method for manufacturing such a display device will be described.

First, a case will be described in which a light-transmitting tube 3 having a convex portion 3a formed on the inner wall surface by the method described above is used.

In this case, first, the colored charged particles 2 and the insulating liquid 1 are filled in the light transmitting tube 3. In this embodiment, the tube 3 has a circular or elliptical cross section, and the tube 3 is made of acrylic resin, polystyrene, polyethylene terephthalate (PET), Polyether sulfone (PE
Although a polymer such as S) or an inorganic material such as glass or quartz can be used, a polymer having high flexibility is particularly preferably used. The diameter of the tube 3 is appropriately determined according to the size of the display pixel.

On the other hand, as the insulating liquid 1, a liquid such as silicone oil, toluene, xylene, or high-purity petroleum is used. When the insulating liquid 1 is colored for color display, a dye or the like is used as a coloring material. Is used by dissolving or dispersing it in the insulating liquid.

As the colored charged particles 2, a material which can be charged in an insulating liquid is used. For example, a mixture of a resin such as titanium oxide (white), aluminum oxide (white), polyethylene, or polystyrene and a coloring agent is used.
Here, as a coloring agent, carbon (black) and known dyes and pigments such as phthalocyanine blue, induslen blue, peacock blue, permanent red, lake red, rhodamine lake, Hansa yellow, permanent yellow, benzine yellow and the like are widely used. Can be used. The size of the particles is usually 0.1
Those having a size of about 50 μm to 50 μm are used.

The colored charged particles and the insulating liquid are placed in a tube 3.
For example, as shown in FIG. 6 (a), the insulating liquid 1 and the colored charged particles 2 are mixed in an appropriate container 17, and one end of the tube 3 is put into the liquid while stirring well. ,
Method of filling while sucking from the other end, FIG. 6 (b)
As shown in (1), after the colored charged particles 2 are uniformly adhered to the inner wall of the tube 3 in advance, the colored liquid particles 2 and the insulating liquid 1 are separately placed in the tube 3 by putting the insulating liquid 1 into the tube 3. There is a method of filling.

After the charged colored particles 2 and the insulating liquid 1 are filled by these methods, both ends of the tube 3 are closed and sealed by heating or the like.

Next, the tube 3 is arranged between the substrates according to the process shown in FIG. That is, first, the first electrode 8 is patterned on the first substrate 4 as shown in FIG. The material of the first substrate 4 is polyethylene terephthalate (PET), polyether sulfone (P
A polymer film such as ES) or an inorganic material such as glass or quartz can be used.

The first electrode 8 may be made of any conductive material that can be patterned. For the transparent electrode, indium tin oxide (ITO) or the like is used. In addition, if necessary, an insulating layer (not shown) is formed on the first electrode.
May be formed to smooth the entire surface.

Next, a second electrode 7 is formed on the second substrate 6 by patterning as shown in FIG. The second substrate 6 is formed of a material having high visible light transmittance and high heat resistance. As a material for forming the second electrode 7, a material having high visible light transmittance is used. Further, after the formation of the second electrode, an insulating layer (not shown) may be formed on the second electrode 7 so as to smooth the entire surface.

Next, a tube 3 filled with the colored charged particles 2 and the insulating liquid 1 is arranged on the first substrate 4 as shown in FIG. In the case of a color display, the colored charged particles 2 of different colors or the tube 3 in which the insulating liquid 1 is sealed are regularly and appropriately arranged.
For example, yellow (Y), magenta (M), cyan (C)
Place in order.

Next, as shown in FIG.
Is arranged above the tube 3 in a direction in which the first and second electrodes 7 and 8 are orthogonal to each other, and is aligned with the first substrate 4. Thereafter, an outer frame (not shown) is provided on the outer peripheral portion. Heat first
The substrate 4 and the second substrate 6 are bonded. At this time, both substrates 4,
The tubes 3 are deformed in accordance with the intervals of 6, and as a result, the tubes can be closely arranged without any gap as shown in FIG. Finally, a voltage applying means is provided to manufacture a display device.

When the first substrate 4 and the second substrate 6 are bonded as shown in (e), the projections 3a periodically formed in the tube are brought into contact vertically as shown in (f). Instead, the adjacent moving spaces communicate with each other. However, the deformation of the tube 3 may cause the convex portions 3a to come into contact with each other up and down, or the moving space S may be closed. In any of these cases, display can be performed without any problem, and uneven distribution of the colored charged particles 2 can be prevented.

Next, a description will be given of a manufacturing process of the display device including a process of forming the convex portion 3a on the tube 3 after filling the colored charged particles 2 and the insulating liquid 1.

First, the charged particles 2 and the insulating liquid 1 are filled in the light transmitting tube 3. On the outer wall surface of the tube 3, a convex structure 9 is formed in advance on one side as shown in FIG. In addition, at this time, a convex part may be provided inside the pipe, but may not be provided. If there is an inner convex portion, it is formed at a position corresponding to the convex structure 9 on the outer wall surface.

Next, the tube is placed on the substrate according to the process shown in FIG. That is, first, the first electrode 8 is patterned on the first substrate 4 as shown in FIG.

Next, a second electrode 7 is patterned on the second substrate 6 as shown in FIG. The insulating liquid 1, the colored charged particles 2, the tube 3, the first substrate 4, the first and second electrodes 7, 8, etc. are filled before the charged charged particles 2 and the insulating liquid 1 are filled. The same material as in the case of using the tube 3 having the convex portion 3a is used.

Next, on the first substrate on which the first electrode 8 is formed, as shown in (c), a convex structure 9 is formed and a tube filled with the colored charged particles 2 and the insulating liquid 1 is formed. Place 3. Here, the convex structure 9 is a structure for forming a convex portion 3a inside the tube 3 filled with the colored charged particles 2 and the insulating liquid 1, and the same material as the tube 3 is used in the process. Although it is easy, it is not always necessary to use a material having a light transmitting property.

Thereafter, as shown in FIG. 6D, the second substrate 6 is placed on the tube 3 with the first and second electrodes 7 and 8 orthogonal to each other.
After that, the substrate is aligned with the first substrate 4, and the outer peripheral portion is bonded by applying heat through an outer frame. And when bonding the first and second substrates 4 and 6 in this way,
The tube 3 adjacent to the convex structure 9 is pressed against the convex structure 9, whereby the tube 3 is deformed, and a convex portion 3a is formed inside the tube 3 as shown in (e).

Here, the example in which the convex structure 9 is formed only on the tube 3 has been described, but the convex structure 9 may be provided on the first substrate or the second substrate side at the same time. Further, after bonding through the outer frame, the convex portion 3a of the tube 3 may come into contact with the upper and lower portions by the convex structure 9, or the moving space S may be completely closed.

As described above, by forming the projections 3a at least on the inner wall surface of the tube 3 on which the colored charged particles 2 move in the direction perpendicular to the upper and lower substrates 4 and 6 at the time of displaying an image, the colored charged particles 2 are formed. 2 can be restricted, and display unevenness can be reduced.

Further, as another method of periodically dividing the tube 3 after filling the charged particles 2 and the insulating liquid 1, a method such as press molding using a jig or physically twisting the tube 3 is also possible. It is. In these cases, the portion of the tube 3 where the insulating liquid 1 and the colored particles 2 are narrowed is referred to as a convex portion 3a as viewed from the inside of the tube 3. In particular,
The press-formed part and the twisted part correspond to this.

Also in these cases, the tube 3 may be closed at the portion where the insulating liquid 1 and the colored charged particles 2 are narrowed. In addition, by raising the temperature such as press molding, the pipe 3
In this case, it is desirable to use a material in which the softening temperature of the tube 3 is lower than the transformation temperature of the colored charged particles 2 and the insulating liquid 1.

As described above, the insulating liquid 1 and the colored charged particles 2 are filled in the light-transmitting tube 3 and a plurality of the tubes 3 are arranged side by side.
Can be easily dispersed. In addition, time and labor-intensive processes such as the formation of the partition walls on the substrate and the uniform dispersion of the colored charged particles 2 and the insulating liquid 1 in the minute regions are not required, so that the cost can be reduced. Besides, the yield can be improved.

Further, since the colored charged particles 2 only move in the tube, even when the display device is used for a long time, the bias of the colored charged particles 2 can be reduced, and display unevenness can be prevented. Further, the display device manufactured by the above method can perform two-color display and color display, and can realize a high viewing angle and a high contrast.

Next, an example of this embodiment will be described. Example 1 In Example 1, a display device was manufactured as follows.

First, polyethylene terephthalate (PE)
T) The light-transmitting tube made of T) is partially heated at a fixed period to shrink a part of the tube to form a convex portion on the inner wall surface of the tube. And an insulating liquid.

Here, a light-transmissive tube having a circular cross section and an inner diameter of 200 μm is used.
It was formed to have a thickness of 0 to 150 μm. Also, as the insulating liquid, silicone oil, and as the colored charged particles,
A mixture of polystyrene and carbon with a particle size of 1
A black one of about 2 μm to 2 μm was used.

Further, as a method for filling the charged tube with the charged particles and the insulating liquid, as shown in FIG. 6A, the insulating liquid 1 and the charged particles 2 are placed in an appropriate container 17. , One end of the tube 3 was put into the liquid with good stirring, and the tube 3 was filled with suction from the other end.
Then, after the filling was completed, both ends of the tube 3 were closed and sealed by heating.

Next, a first electrode 8 made of ITO was formed on a light-transmissive first substrate 4 made of a PET film having a thickness of 200 μm.
Was formed and patterned in a line shape (see FIG. 7A). In addition, ITO was formed as a second electrode 7 on a light-transmitting second substrate 6 made of a PET film having a thickness of 200 μm, and was patterned into a line by photolithography and dry etching (see FIG. 7B).

Next, the tubes 3 filled with the colored charged particles 2 and the insulating liquid 1 were arranged on the first substrate 4 configured as described above (see FIG. 7C). After that, the second substrate 6 is disposed above the tube 3 so that the first and second electrodes 7 and 8 are orthogonal to each other (see FIG. 7D).
The substrate 4 and the second substrate 6 were aligned, and heat was applied to the outer peripheral portion via an outer frame to bond the first and second substrates 4 and 6 together.

As a result, the upper and lower portions of the tube 3 are
, And the pipes were placed in close contact with no gap (see (e) of FIG. 7). When the tube 3 is deformed in this manner, the upper and lower convex portions 3a inside the tube approach with the deformation of the tube 3, thereby forming a moving space S that at least restricts the movement of the colored charged particles 2 ( (See (f) of FIG. 7). Finally, a voltage applying means was provided to obtain a display device.

Next, display was performed using the display device thus manufactured. Note that the applied voltage was ± 50 V. Here, since the colored charged particles 2 used in Example 1 were positively charged in the silicone oil, they moved onto the electrode to which a negative voltage was applied. Accordingly, when the electrode to which the negative voltage is applied is the first electrode 8, the black colored charged particles 2 move on the first electrode (see FIG. 2A).
The display surface became white display.

On the other hand, if the electrode to which the negative voltage is applied is the second electrode 7, the black colored charged particles 2 move on the second electrode (see FIG. 2B), so Black color was observed. The response speed at this time is 30 msec.
It was below. Further, no display unevenness due to uneven distribution of the colored charged particles 2 was observed.

Example 2 In Example 2, a display device was manufactured as follows.

First, the outside of the tube having no convex portion inside,
A convex structure having a μm pitch and a film thickness of 30 μm was formed (see FIG. 8C), and thereafter, the same colored charged particles and insulating liquid as in Example 1 were filled. As a method for filling the charged tube with the charged particles and the insulating liquid, as shown in FIG. 6B described above, the charged particles 2 are uniformly attached to the inner wall of the tube 3 beforehand. A method was used in which one end of the tube 3 was placed in an insulating liquid and filled while sucking from the other end. Then, after the filling was completed, both ends of the tube were closed and sealed by heating.

Next, the first substrate 4 is formed in the same manner as in the first embodiment.
After the first electrode 8 was formed thereon (see FIG. 8A), the second electrode 7 was pattern-formed on the second substrate 6 (see FIG. 8B). Thereafter, a convex structure 9 is formed on the first substrate 4 on which the first electrode 8 is formed, and the tube 3 filled with the colored charged particles 2 and the insulating liquid 1 is arranged (see FIG. 8C). ).

Next, after disposing the second substrate 6 above the tube 3 (see FIG. 8D), the second substrate 6 is aligned with the first substrate 4, and thereafter, the outer peripheral portion is put through an outer frame. The first and second substrates 4 and 6 were bonded by applying heat. As a result, the upper and lower portions of the tube 3 came into contact with the substrates 4 and 6 and became smooth, and the tubes were closely arranged without any gap. The inner wall surface of the tube 3 on the side in contact with the tubes is formed by a convex structure 9 on the outer side of the tube 3.
a was formed (see FIG. 8E). And finally,
A display device was manufactured by providing a voltage applying unit.

Next, display was performed in the same manner as in Example 1 using the display device thus manufactured. Note that the applied voltage was ± 50 V. Also, in the second embodiment, the response speed is 30 msec or less,
No display unevenness due to uneven distribution was observed.

Example 3 In Example 3, a display device was manufactured as follows.

First, polyethylene terephthalate (PE)
T) by periodically heating the light-transmissive tube 3 made of T) to form a convex portion 3a on the inner wall surface of the tube 3;
Was charged with colored charged particles 2 and insulating liquid 1.

The light-transmitting tube 3 has a circular cross section and an inner diameter of 200 μm.
It was formed at a pitch of μm. Further, as the insulating liquid 1, three types of liquids in which a dye is dissolved in silicone oil and colored in yellow (Y), magenta (M), and cyan (C) are used. Titanium white fine particles having a particle size of about 1 μm to 2 μm were used.

After the filling is completed, both ends of the tube 3 are closed and sealed by heating, and the three-colored tube 3 is colored.
Was prepared.

Next, a first electrode 8 is formed on the first substrate in the same manner as in the first embodiment (see FIG. 7A).
The second electrode 7 was formed on the second substrate 6 (see FIG. 7B).

Next, the three colored tubes 3 were sequentially arranged on the first substrate 4 configured as described above (see FIG. 7C). After this, the second substrate 6 is moved to the first
And the second electrodes 7 and 8 are arranged above the tube 3 so as to be orthogonal to each other (see FIG. 7 (d)).
The substrates 4 and 6 were aligned, and the first and second substrates 4 and 6 were bonded by applying heat to the outer peripheral portion via an outer frame.

As a result, the upper and lower portions of the tube 3 are
, And the pipes were placed in close contact with no gap (see (e) of FIG. 7). When the tube 3 is deformed in this manner, the upper and lower convex portions 3a inside the tube approach with the deformation of the tube 3, thereby forming a moving space S that at least restricts the movement of the colored charged particles 2 ( (See (f) of FIG. 7). Finally, a voltage applying means was provided to obtain a display device.

Next, display was performed using the display device thus manufactured. Note that the applied voltage was ± 50 V. Here, since the colored charged particles 2 used in Example 3 were negatively charged in the silicone oil, they moved onto the electrode to which a positive voltage was applied. Thus, when the electrode to which the positive voltage is applied is the first electrode 8, the white colored charged particles 2 move to the first electrode 8 portion (see FIG. 4), so that the color of each insulating liquid 1 is viewed from the display surface. Could be observed.

On the other hand, when the electrode to which the positive voltage was applied was the second electrode 7, the white colored charged particles 2 moved to the second electrode 7, and the display surface displayed white. At this time, the response speed was 30 msec or less, and no display unevenness due to uneven distribution of the colored charged particles was observed. Further, when a combination of elements forming the respective colors of yellow (Y), cyan (C), and magenta (M) was formed, color display could be performed.

Example 4 In Example 4, a display device was manufactured as follows.

First, polyethylene terephthalate (PE)
The charged tube and the insulating liquid were filled in a light-transmitting tube made of T). Here, a tube having a circular cross section and an inner diameter of 200 μm was used as the light transmitting tube. Silicone oil is used as the insulating liquid, and polystyrene is used as the colored charged particles, and the particle size of the three colors obtained by mixing yellow (Y), magenta (M), and cyan (C) colorants is used. Of about 1 μm to 2 μm was used.

Further, as a method for filling the charged particles and the insulating liquid into the tube 3, as shown in FIG. Was uniformly adhered, and one end of the tube 3 was placed in an insulating liquid and filled while sucking from the other end. Then, after the filling was completed, both ends of the tube 3 were closed and sealed by heating.

Thereafter, press forming was performed using a jig to form a convex portion on the inner wall surface of the tube 3. The pitch of the projections at this time was 200 μm. The same operation was performed for the other two-color particles. Then, a tube 3 in which particles of three colors were separately sealed was produced in this manner.

Next, the first electrode 8 is formed on the first substrate in the same manner as in the first embodiment (see FIG. 7A).
The second electrode 7 was formed on the second substrate 6 (see FIG. 7B).

Next, the three colored tubes 3 were sequentially arranged on the first substrate 4 configured as described above (see FIG. 7C). After that, the second substrate 6 is disposed above the tube 3 so that the first and second electrodes 7 and 8 are orthogonal to each other (see FIG. 7D). The substrates 4 and 6 were aligned, and the first and second substrates 4 and 6 were bonded by applying heat to the outer peripheral portion via an outer frame.

As a result, the upper and lower portions of the tube 3 are
, And the pipes were placed in close contact with no gap (see (e) of FIG. 7). When the tube 3 is deformed in this manner, the upper and lower convex portions 3a inside the tube approach with the deformation of the tube 3, thereby forming a moving space S that at least restricts the movement of the colored charged particles 2 ( (See (f) of FIG. 7). Finally, a voltage applying means was provided to obtain a display device.

Next, display was performed using the display device thus manufactured. Note that the applied voltage was ± 50 V. Here, since the colored charged particles 2 used in Example 4 were positively charged in the silicone oil, they moved onto the electrode to which a negative voltage was applied. As a result, when the electrode to which the negative voltage is applied is the first electrode 8, the colored and charged particles 2 move on the first electrode 8 (see FIG. 5). Was observed.

On the other hand, when the electrode to which the negative voltage is applied is the second electrode 7, the colored charged particles 2 move on the second electrode, and the color of each colored charged particle 2 can be observed from the display surface. . At this time, the response speed was 30 msee or less, and no display unevenness due to uneven distribution of the colored charged particles 2 was observed. In addition, when the elements forming the respective colors of yellow, cyan, and magenta were combined and formed, color display could be performed.

Example 5 In Example 5, a tube having an inner diameter of 30 μm and a pitch of projections of 30 μm was used, the distance between the substrates was reduced to 25 μm, and 0.5 μm as colored charged particles was used. A display device was manufactured in the same process as in Example 1 using a substrate having a thickness of about 1 μm.

Then, display was performed in the same manner as in Example 1 using the display device thus manufactured. In addition,
The applied voltage was ± 50V. Here, in Example 5, since the distance between the substrates was shortened to shorten the migration distance,
The response speed became 5 msec or less, and high-speed response became possible. Further, no display unevenness due to uneven distribution of the colored charged particles was observed.

[0107]

As described above, according to the present invention, the insulating liquid and the colored charged particles are filled in a tube having a light-transmitting property and having convex portions formed regularly on the inner wall surface in the longitudinal direction. At the same time, by disposing the tubes filled with the insulating liquid and the colored charged particles in close contact between the first substrate and the second substrate, the colored charged particles can be uniformly dispersed, Thereby, display unevenness can be reduced. Further, since time-consuming and troublesome steps such as formation of partition walls on a substrate and uniform dispersion of colored charged particles and insulating liquid in minute regions are not required, manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of an electrophoretic display device which is a display device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a part of a cross section of the electrophoretic display device.

FIG. 3 is a view showing a cross section of the electrophoretic display device in a tube longitudinal direction.

FIG. 4 is a cross-sectional view of the electrophoretic display device that performs color display using insulating liquids of a plurality of colors.

FIG. 5 is a cross-sectional view of the electrophoretic display device that performs color display using colored charged particles of a plurality of colors.

FIG. 6 is a diagram showing a method of filling the above tube with an insulating liquid and colored charged particles.

FIG. 7 is a diagram illustrating a method of manufacturing the electrophoretic display device.

FIG. 8 is a diagram showing a method for manufacturing the electrophoretic display device according to Example 2 of the above embodiment.

FIG. 9 illustrates a configuration of a conventional electrophoretic display device.

[Explanation of symbols]

 1, 10, 11, 12 Insulating liquid 2, 13, 14, 15 Colored charged particles 3 Tube 3a Convex part 4 First substrate 6 Second substrate 7 Second electrode 8 First electrode 9 Convex structure 17 Container S Moving space 31 Electrophoretic particles 32 Insulating liquid 33 Electrode 34 Electrode

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tsutomu Ikeda 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 5C094 AA03 AA43 AA44 BA75 BA84 CA23 EB02 EC04 FB01 GB01

Claims (17)

[Claims] 1. Colored charged particles dispersed in an insulating liquid, and a first electrode and a second electrode for applying a voltage to the colored charged particles, wherein the first and second electrodes are applied to the first and second electrodes. The colored charged particles by the first electrode or the second
A display device that performs display by moving in the direction of an electrode, wherein the insulating liquid and colored charged particles are filled in a light-transmissive tube, and the inner wall surface of the tube has a longitudinal direction of the colored charged particles. A convex portion for preventing movement of the tube is regularly formed in the longitudinal direction of the tube, and the tube is formed of a first substrate on which the first electrode is formed, and a second substrate on which the second electrode is formed. A display device, wherein a plurality of the display devices are disposed in close contact with each other. 2. The method according to claim 1, wherein the colored charged particles include the first and second charged particles.
The voltage applied to the electrodes causes two adjacent
2. The display device according to claim 1, wherein a range defined by the two convex portions is moved in a direction perpendicular to the first and second substrates. 3. 3. The display device according to claim 1, wherein the projection is formed on an inner wall surface of the tube in a direction perpendicular to at least the first and second substrates. 4. The display device according to claim 1, wherein the convex portion of the tube is formed by heating and shrinking the tube. 5. The display device according to claim 1, wherein the convex portion of the tube is formed by press-molding the tube. 6. The tube according to claim 1, wherein the convex portion of the tube is formed by pressing the tube by a convex structure formed on at least one side of the outside of the tube. The display device according to any one of the above. 7. The display device according to claim 1, wherein the tube is made of a polymer. 8. The insulating liquid is colored in a different color from the colored charged particles, and a tube filled with the different colored insulating liquid is regularly placed between the first substrate and the second substrate. The display device according to claim 1, wherein the display device is arranged. 9. The display device according to claim 1, wherein tubes filled with the colored charged particles of different colors are regularly arranged between the first substrate and the second substrate. 10. The display device according to claim 1, wherein at least one of the first substrate and the second substrate has a light transmitting property. 11. The display device according to claim 1, wherein the first substrate and the second substrate are polymer films. 12. The display device according to claim 1, wherein at least one of the first electrode and the second electrode has a light transmitting property. 13. The display device according to claim 1, wherein color display is performed by using one of the color of the colored charged particles and the color of the insulating liquid. 14. Colored charged particles dispersed in an insulating liquid, and a first electrode and a second electrode for applying a voltage to the colored charged particles, wherein the first electrode and the second electrode are applied to the first electrode and the second electrode. A method of manufacturing a display device in which the colored charged particles are moved in the direction of the first electrode or the second electrode by a voltage to perform display, wherein the insulating liquid and the colored charged particles are filled in a light-transmitting tube. A step of regularly forming in the longitudinal direction convex portions for preventing the movement of the colored charged particles on the inner wall surface of the tube; and forming the tubes filled with the insulating liquid and the colored charged particles, Manufacturing the display device, comprising: placing the first substrate having one electrode formed thereon and the second substrate having the light transmissive electrode formed thereon in close contact therewith. Method. 15. The display according to claim 14, wherein the convex portion of the tube is formed by heating and shrinking the tube before filling the insulating liquid and the colored charged particles. Device manufacturing method. 16. The tube according to claim 14, wherein the convex portion of the tube is formed by press-molding the tube before or after filling with the insulating liquid and the colored charged particles. The manufacturing method of the display device according to the above. 17. The convex portion of the tube is filled with the insulating liquid and the colored charged particles, and then, when the tube is placed in close contact with the first and second substrates, at least one side outside the tube. 15. The tube is formed by pressing the tube by the convex structure formed in the tube.
The manufacturing method of the display device according to the above.