JP3501679B2 - Display device manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a display device in which charged electrophoretic particles are moved for displaying.

[0002]

2. Description of the Related Art In recent years, with the development of information equipment, there has been an increasing need for low power consumption and thin display devices, and research and development of display devices meeting these needs have been actively conducted. Among them, the liquid crystal display device, which electrically controls the alignment of liquid crystal molecules to change the optical characteristics of the liquid crystal, has been actively developed and commercialized as a display device that can meet the above needs.

Har is one of such display devices.
old D.D. An electrophoretic display device proposed by Lees et al. (US Pat. No. 3,612,758) is known. FIG. 8 is a diagram showing the structure and operation principle of the electrophoretic display device. The display device P ₃ includes a pair of substrates 1a and 1b arranged with a predetermined gap therebetween. Electrodes 36 and 37 are formed on the substrates 1a and 1b, respectively. Further, in the gap between the substrates, a large number of charged electrophoretic particles 5 that are positively charged and colored, and a migration dispersion liquid 4 in which a dye is dissolved and colored in a color different from that of the charged electrophoretic particles 5 are formed. A plurality of pixels 2 are arranged along the plane direction of the substrate by arranging partition walls 3 further.
(Only one pixel is shown in the drawing) to prevent uneven distribution of the charged electrophoretic particles 5 and to define the substrate gap.

In such a display device P ₃ , the same figure is used.
As shown in (a), when a negative voltage is applied to the electrode 37 on the lower side in the drawing and a positive voltage is applied to the electrode 36 on the upper side in the drawing, the charged electrophoretic particles 5 that are positively charged move downward. When the display devices are gathered so as to cover the side electrodes 37 and viewed from the direction A in the drawing, the same color as the electrophoretic dispersion liquid 4 is displayed. On the other hand, as shown in FIG. 2B, when a positive voltage is applied to the lower electrode 37 in the figure and a negative voltage is applied to the upper electrode 36 in the figure, the positively charged The electrophoretic particles 5 gather to cover the upper electrode 36, and when the display device is viewed from the direction A in the figure, the same color as the charged electrophoretic particles 5 is displayed. By performing such driving in pixel units, an arbitrary image is displayed by a large number of pixels.

By the way, in the above-mentioned display device P ₃ , it is desirable that the color density of each pixel 2 is substantially uniform. For that purpose, the charged electrophoretic particles 5 are arranged in substantially equal amounts in each pixel. There is a need. As a manufacturing method therefor, there have been the following methods. That is, in the method disclosed in JP-A-64-86117, the partition wall 3 is made of a material that swells (increases the volume) by being immersed in the electrophoretic dispersion liquid 4, and the partition wall 3 is prepared in advance. When the particles are not swollen, the electrophoretic dispersion liquid 4 is injected together with the charged electrophoretic particles 5, and then the partition walls 3 are formed by the electrophoretic dispersion liquid.
To form the pixels 2 by swelling the particles, or a method disclosed in JP-A-2-223935, in which the partition walls 3 are formed on one of the substrates 1a or 1b, and the electrophoretic particles 5 are dispersed. There is a method in which the flexible film (the other substrate) is successively pressure-bonded in such a state that it is immersed in the dispersion liquid 4 thus prepared.

[0006]

However, even if the above methods and methods are used, there is a limit in arranging the charged electrophoretic particles 5 in substantially equal amounts in each pixel, and the color density of each pixel 2 is limited. There is a problem that they are not equal and display quality is deteriorated.

The reason why the charged electrophoretic particles 5 cannot be arranged in a substantially equal amount for each pixel is as follows. That is, in the above method, the injection of the electrophoretic dispersion liquid 4 is performed in the direction along the substrate surface from one end to the other end of the substrate, but since the charged electrophoretic particles 5 are charged, the injection is performed. This is because the charged electrophoretic particles 5 adhere to the surfaces of the substrate and the partition walls 3 on the upstream side in the direction and do not spread to every corner of the substrate gap, and the density of the charged electrophoretic particles 5 is high in the injection direction upstream side and low in the injection direction downstream side. . In addition, in the above method, the dispersion liquid 4 of each pixel is dispersed for various reasons (for example, when the height of the partition wall 3 is different or when the flexible film is sequentially pressed). This is because the amount is different, and accordingly, the amount of the charged electrophoretic particles 5 is not equal for each pixel.

[0008] Therefore, an object of the present invention is to provide a method of manufacturing a display device which prevents deterioration of display quality.

[0009]

The present invention has been made in consideration of the above circumstances, and includes a pair of substrates arranged with a predetermined gap therebetween and the predetermined gap along the surface of the substrate. A partition member arranged so as to be divided into a plurality of pixels, an electrophoretic dispersion liquid and a large number of charged electrophoretic particles respectively disposed in the plurality of pixels, so as to face the electrophoretic dispersion liquid and the electrophoretic migration particles. In a method of manufacturing a display device for manufacturing a display device including a first electrode and a second electrode respectively arranged for each pixel, a suction member temporarily adsorbing the charged electrophoretic particles is provided with a predetermined gap. It is arranged at a position facing one of the pair of substrates before being arranged in an open state, and then the charged electrophoretic particles are attached to the one substrate from the adsorbing member. To do.

[0010]

DETAILED DESCRIPTION OF THE INVENTION Referring to FIGS.
An embodiment of the present invention will be described.

First, the structure of a display device manufactured according to the present invention will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the display device manufactured according to the present invention includes a pair of substrates 1a and 1b arranged with a predetermined gap, and the substrate 1 having the predetermined gap.
A partition member 3 arranged so as to be divided into a plurality of pixels 2 along the planes a and 1b, a migration dispersion liquid 4 and a large number of charged electrophoretic particles 5 respectively arranged in the plurality of pixels 2.
And a first electrode 6 arranged in each pixel 2 so as to face the electrophoretic dispersion liquid 4 and the charged electrophoretic particles 5.
(Reference numeral 16 in FIG. 2) and the second electrode 7 (reference numeral 1 in FIG. 2)
7) and are provided. The charged electrophoretic particles 5 are charged to have a predetermined polarity.

In this case, the first electrode and the second electrode are as shown in FIG.
2 may be supported on the same substrate 1b as indicated by reference numerals 6 and 7, and separate substrates 1b may be supported as indicated by reference numerals 16 and 17 in FIG.
It may be supported by a and 1b.

When the first electrode 6 and the second electrode 7 are supported on the same substrate 1b, as shown in FIG. 1, in each pixel 2, the first electrode 6 faces the electrophoretic dispersion liquid 4. The area S _{1 of the} (exposed) portion (hereinafter referred to as “exposed area S ₁ of the first electrode 6”) is made larger than the exposed area S ₂ of the second electrode 7, and the first electrode The portion of 6 facing the electrophoretic dispersion liquid 4 is colored with a first color (for example, white, or colorless and transparent when the display device is a transmissive type), and the charged electrophoretic particles 5 are colored with a second color. Coloring (for example, black) is preferable. Here, the first color may be colored as long as it is applied to the portion where the first electrode 6 faces the electrophoretic dispersion liquid 4 as described above, and even if the first electrode 6 itself is colored, The film covering the first electrode 6 (ex. Electrode protective film) may be colored. In such a case, as shown in FIG. 1, the second color (for example, black) is displayed in the pixel 2 in which the charged electrophoretic particles 5 are collected so as to cover the first electrode 6, and the second color is displayed.
In the pixels 2 gathered so as to cover the electrodes 7, the first color (for example, white) is displayed. By the way, the display contrast in this case is different from that of the first electrode 6 and the second electrode 6.
It largely depends on the exposed area ratio of the electrode 7 (= exposed area of the second electrode 7 / exposed area of the first electrode 6). The larger the exposed area ratio, the smaller the contrast, and the smaller the exposed area ratio, the more the contrast. growing. In order to realize a large contrast, this exposed area ratio may be set to about 1/2 to 1/4. In addition, in FIG. 1, the first electrode 6 is
The electrodes 7 and 7 are arranged so as to overlap with each other, and the insulating layer 8 is arranged between them to be insulated. However, it is not limited to this, and both electrodes 6 and 7 may be arranged so as not to overlap. .

On the other hand, when the first electrode 16 and the second electrode 17 are supported on separate substrates 1a and 1b as shown in FIG. 2, at least one of the electrodes 16 (the electrode arranged on the observer side). 16) is made transparent and is formed on almost the entire pixel 2 (at least on almost the entire pixel 2 although it is not always necessary to form it on the entire substrate), and the electrophoretic dispersion liquid 4 is made into a first color by a pigment. (For example, blue) and the charged electrophoretic particles 5 have a second color (for example, black).
Color it. In such a case, in the pixel 2 in which the charged electrophoretic particles 5 are gathered so as to cover the electrode 17, as shown in FIG. 2, when the display device P ₂ is viewed from the direction of the arrow A in the drawing, only the electrophoretic dispersion liquid 4 is present. The charged electrophoretic particles 5 are not visually recognized, and the electrophoretic dispersion liquid 4 displays the first color. Further, in the pixel 2 in which the charged electrophoretic particles 5 are collected so as to cover the electrode 16, only the charged electrophoretic particles 5 colored in the second color are visually recognized, and the electrophoretic dispersion liquid 4 is not visually recognized, and the second color display is performed. Will be performed. In such a case, since the display contrast does not depend on the exposed area ratio of the first electrode 16 and the second electrode 17, it is sufficient if at least one of the electrodes 16 is formed on almost the entire pixel 2 as described above. From the viewpoint of display contrast, it is not necessary to adjust the exposure area ratio of both electrodes 16 and 17. That is, from the viewpoint of display contrast, the other electrode 1
It is not necessary to make the exposed area of 7 smaller than the exposed area of the one electrode 16, and for example, both electrodes 16 and 17 may be formed on almost the entire pixel 2.

By the way, regardless of whether the first electrodes 6 and 16 and the second electrodes 7 and 17 are supported by the same substrate 1b, or whether they are supported by different substrates 1a and 1b, these electrodes 6 , 7, 16 and 17 may or may not be formed in contact with the substrates 1a and 1b. Further, on the surfaces of these electrodes 6, 7, 16 and 17, it is preferable to form an insulating layer 8, an electrode protective layer 9 and a black matrix pattern as needed.

Further, the above-mentioned first electrode 6 and second electrode 7
(Or, the polarity of the potential difference between the first electrode 16 and the second electrode 17) is configured to be changed independently in each pixel 2. The method is as follows: * Both the first electrode 6 and the second electrode 7 (or the first electrode 1
6 and the second electrode 17) are formed in a dot shape in each pixel 2 and a voltage of arbitrary polarity is applied to each of the electrodes 6, 7 or 16, 17 (not shown), or * As shown in FIG. 1 and FIG. 2, one electrode 6, 16 is formed over almost the entire substrate 1a or 1b to be a common electrode, and the other electrode 7, 17 is formed in a dot shape for each pixel 2. However, one of the electrodes 6 and 16 serving as the common electrode may be grounded or the like to be held at a reference potential, and a voltage of arbitrary polarity may be applied to the other electrodes 7 and 17. Here, the magnitude of the applied voltage is
It may be adjusted according to the charge amount of the charged electrophoretic particles 5 and the pitch between the electrodes, but normally, several tens of V is required.

On the other hand, the display device P ₁ may be a transmissive type or a reflective type. The arrow A shown in FIG.
When observed from the direction of, the first electrode 6 shown in FIG.
When the display device P ₁ is a transmissive type, a transparent electrode such as ITO (Indium Tin Oxide) is used for
When the display device P ₁ is of a reflective type, a metal electrode such as Al may be used. In addition, the first electrode 6 shown in FIG.
A transparent electrode such as ITO (indium tin oxide) may be used.

Further, the second electrode 7 shown in FIG.
Although a metal material such as Ti or Ti may be used, a black material, such as TiC, is preferably used.

Furthermore, acrylic resin or polyimide resin may be used for the insulating layer 8. When the display device is of a reflective type, the insulating layer 8 may be mixed with white fine particles such as alumina to give a function as a scattering layer.

On the other hand, general glass can be used for the above-mentioned substrates 1a and 1b, but polyethylene terephthalate (PET) is used to make the display device flexible.
Alternatively, a plastic film such as polyether sulfone (PES) may be used.

The partition member 3 is made of silicone rubber,
Fluorine rubber, acrylic rubber, or other photosensitive resin may be used.

Further, the electrophoretic particles 5 are mainly composed of a polymer resin such as polystyrene or polyethylene and mixed with a colorant such as carbon, a pigment such as titanium oxide or aluminum oxide, or a polymer resin. Those coated with can be preferably used. It is advisable to mix a charge control agent, etc., if necessary, and the particle size is 0.1
It is preferably ˜15 μm.

Furthermore, it is preferable to use, as the electrophoretic dispersion liquid 4, a liquid in which the charged electrophoretic particles 5 are favorably charged and has a low viscosity. Specifically, silicone oil, xylene, toluene, isoper, etc. are used. good. Further, as the electrophoretic dispersion liquid 4, one having a large specific gravity is used if necessary,
It is preferable that the specific gravity of the electrophoretic dispersion liquid 4 and the specific gravity of the charged electrophoretic particles 5 be substantially equal.

In such a display device, different colors may be displayed in a plurality of adjacent pixels 2 and a full-color image may be displayed by combining these colors.

Next, a method of manufacturing the display devices P ₁ and P ₂ will be described with reference to FIGS.

When manufacturing the display devices P ₁ and P ₂ , _{one of} the pair of substrates 1a and 1b is arranged before the pair of substrates 1a and 1b are arranged with a predetermined gap. The large number of charged electrophoretic particles 5 are scattered and attached to 1a or 1b (see FIGS. 3 (d), 4 (c) and 5 (d)).

Dispersion of the charged electrophoretic particles 5 is carried out on the substrate (FIG. 3 (d) and FIG. 4) forming the partition wall member 3.
(see (c)), * the substrate on which the partition wall member 3 is not formed (see FIG. 5 (d)). In addition, in FIGS. 3D and 4C, although the partition member 3 is formed and the pixels 2 are formed and then the charged electrophoretic particles 5 are dispersed, before the partition member 3 is formed. The spraying may be performed on the substrate 1a or 1b (not shown).

Although any method may be used to disperse the charged electrophoretic particles 5, as shown in FIGS. 4 (b) and 5 (c), the charged electrophoretic particles 5 charged to one polarity. The adsorption member 22 (A) that has temporarily adsorbed is disposed at a position facing the one substrate 1a or 1b, and then the charged electrophoretic particles 5 are transferred from the adsorption member 22 (A) to the one substrate. It is better to fly to 1a or 1b.

It should be noted that the adsorption of the charged electrophoretic particles 5 on the adsorption member 22 (A) described above is preferably performed at the position C corresponding to the pixel of the display device. Here, the "position C corresponding to the pixel of the display device" means a position which can face each pixel when the pixel is already formed by the partition member 3 as shown in FIG. 4 (c). As shown in FIG. 5D, the charged electrophoretic particles 5 are applied to the substrate on which the pixels are not formed.
In the case of spraying, the position means a position which can face the "portion where the pixel is formed".

Here, the suction member 22 (A) shown in FIGS. 4 (b) and 5 (c) is a plate-shaped member (hereinafter referred to as "suction plate"), but need not be limited to this. Alternatively, a drum-shaped member (hereinafter referred to as "suction drum") may be used as indicated by reference numeral 22 (B) in FIG.

When the charged electrophoretic particles 5 are made to fly from the adsorption member 22 to the one substrate 1a or 1b, a portion C (adsorption area C) of the adsorption member 22 on which the charged electrophoretic particles are adsorbed. Is the pixel 2 of the display device
It is necessary to oppose to the "portion where the pixel is formed" when the charged electrophoretic particles 5 are dispersed on the substrate on which the pixel is not formed as shown in FIG. 5 (d). When the suction plate 22 (A) is used as the suction member, the suction plate 22 (A)
May be placed at a predetermined position with respect to the one substrate 1a or 1b. When the suction drum 22 (B) is used as the suction member, the suction drum 22 (B) is used as in a general copying machine. It is necessary to rotate and drive the one substrate 1a or 1b in the surface direction in synchronization with the rotation by a driving unit (not shown).

By the way, the adsorption of the charged electrophoretic particles 5 to the adsorbing members 22 (A) (B) is made of the material used for the photosensitive drum of the copying machine. Then, * the adsorption members 22 (A) and (B) are uniformly charged, and static electricity is formed by erasing light by irradiating light such as laser light to form an electrostatic latent image. This may be achieved by causing the charged electrophoretic particles 5 to be adsorbed on the portions C of (A) and (B) where the charge has not been removed.

Here, the adsorption amount of the charged electrophoretic particles 5 adsorbed to the adsorption member 22 (A) per unit area may be controlled by controlling the charge amount of the adsorption member 22 (A). Electrophoretic particles 5 in each adsorption area C
May be equal or different.

On the other hand, as a method for causing the charged electrophoretic particles 5 to fly from the adsorbing member 22 to the one substrate 1a or 1b, * a method of destaticizing the adsorbing member 22 (A) or * as shown in FIG. A voltage is applied to the adsorption electrode 21 arranged near the one substrate 1a or 1b to charge the one substrate 1a or 1b to another polarity (a polarity different from the charging polarity of the charged electrophoretic particles 5). The method of causing electrostatic attraction force to fly the charged electrophoretic particles 5 can be mentioned.

The adsorption electrode 21 shown in FIG. 6 is separable from the one substrate 1a or 1b, and the back side of the one substrate 1a or 1b (the substrate 1a) when the charged electrophoretic particles 5 are sprayed. Alternatively, it is arranged on the side opposite to the side on which the charged electrophoretic particles 5 are scattered based on 1b), but the arrangement is not limited to this. For example, as shown in FIG. 7, the first electrode 6 is formed on the one substrate 1a or 1b before the charged electrophoretic particles 5 are dispersed, and the first electrode 6 is formed on the substrate 1a or 1b. When spraying No. 5, it may be used as the adsorption electrode. That is, when the charged electrophoretic particles 5 are sprayed, a voltage is applied to the first electrode 6 so that the portion to which the charged electrophoretic particles 5 are attached has another polarity (the charge polarity of the charged electrophoretic particles 5 is different from that of the charged electrophoretic particles 5). Are charged with different polarities). Reference numeral 23 in FIG. 6 denotes a charged electrophoretic particle supply mechanism for storing the charged electrophoretic particles 5 in a state of being charged to one polarity, and reference numeral 24 denotes the adsorption electrode 2.
1 shows a power supply connected to 1 to apply a voltage.

On the other hand, the electrophoretic dispersion liquid 4 is arranged on the plurality of pixels 2 after the spraying of the large number of charged electrophoretic particles 5 (the electrified electrophoretic particles 5 are removed from the adsorption member 22 to the first one). It is preferable to perform it after the flight to the substrate 1a or 1b).

The electrophoretic dispersion liquid 4 may be placed before the pair of substrates 1a and 1b are placed with a predetermined gap therebetween (see FIGS. 3 (e) and 4 (d)). Alternatively, it may be performed after the pair of substrates 1a and 1b are arranged with a predetermined gap therebetween (see FIGS. 5 (e) and 5 (f)).

In the latter case (that is, when the electrophoretic dispersion liquid 4 is placed after the pair of substrates 1a and 1b are placed with a predetermined gap left therebetween), the partition member 3 is used.
A through hole 3a (preferably, a through hole having a size such that only the electrophoretic dispersion liquid 4 can move from the pixel 2 to another pixel 2 and the charged electrophoretic particles 5 cannot move) is formed in each pixel 2. It is necessary to keep in communication. As a method of forming such through-holes 3a, as shown in FIG. 5 (a), after forming the through-hole forming resist pattern 18 in a line form from the substrate end to the substrate end, the resist pattern 18 is formed. There is a method in which the partition wall 3 is patterned so as to cover the above, and then the through hole forming resist pattern 18 is dissolved and removed. When the first electrode 16 and the second electrode 17 are supported on separate substrates 1a and 1b as shown in FIG.
The position where a is formed is at one electrode (first electrode 1 in the figure).
6) near the other electrode (second electrode 17 in the figure)
When pouring the dispersion liquid 4 for migration into a position away from the
By applying a voltage having an appropriate polarity to these electrodes 16 and 17, the charged electrophoretic particles 5 are attracted to a position apart from the through holes 3a, and the charged electrophoretic particles 5 close the through holes 3a and the electrophoretic dispersion liquid 4 is formed. It is better not to block the injection of.

On the other hand, when the electrophoretic dispersion liquid 4 is arranged after the spraying of the charged electrophoretic particles 5, the electrophoretic particles 5 already arranged in substantially equal amounts for each pixel are distributed between the pixels. Since they may move to each other and the arrangement state thereof may be impaired, the first electrode 6 and the second electrode 7 may be provided before the charged electrophoretic particles 5 fly from the adsorption member 22 to the one substrate 1a or 1b. At least one of the electrodes (or the first electrode 16 and the second electrode 17) and the partition wall member 3 are formed on the one substrate 1a or 1b, and a voltage is applied to the formed electrode for each pixel. When the charged electrophoretic particles 5 are electrostatically adsorbed on the substrate 2 or when the electrophoretic dispersion liquid 4 is placed after the substrates are bonded together, the electrophoretic dispersion liquid 4 is vaporized and injected into the substrate gap. Then cooled and liquefied It is better to let it go.

Next, the effect of this embodiment will be described.

According to this embodiment, the electrophoretic particles 5 are charged.
Are arranged in substantially the same amount for each pixel, so that the density of the color displayed by the particles is also substantially equal for each pixel, and the display quality of the produced display device is good.

In addition, the electrophoretic dispersion liquid 4 is arranged in the plurality of pixels 2 by applying a voltage to at least one of the first electrode 6 and the second electrode 7 so that the charged electrophoretic particles 5 are applied to each pixel 2. When electrostatically adsorbed, the arrangement state of the charged electrophoretic particles 5 (arrangement state in which substantially equal amounts are arranged in each pixel) can be prevented from being damaged.

Further, according to the present embodiment, the electrophoretic particles 5 are applied to the respective pixels 2 by using the adsorbing member 22 (A).
Since the method of transferring (flying) is used, it becomes easy to make the colors of the charged electrophoretic particles 5 different in a plurality of adjacent pixels 2, and a display device for displaying a full-color image can be produced by a simple method.

[0045]

The present invention will be described in more detail below with reference to examples.

Example 1 In this example, the display device P ₁ shown in FIG. 1 was manufactured by the method shown in FIG.

That is, as shown in FIG. 1, the first electrode 6
Is formed on the entire surface of one substrate 1b, and its first electrode 6
An insulating layer 8, a second electrode 7, and an electrode protective layer 9 were sequentially formed on the surface of the.

Polyethylene terephthalate (PET) was used for the substrates 1a and 1b, and Al was used for the first electrode 6 in order to serve also as a reflection layer. The insulating layer 8 is made of acrylic resin mixed with alumina fine particles to have a function as a scattering layer.
For this, TiC that exhibits a dark black color was used. Further, the partition wall (partition wall member) 3 is made of silicone rubber, and the electrophoretic particles 5 are mainly composed of polystyrene, which is mixed with carbon and a charge control agent (particle size 2 μm) and has a negative polarity. The one charged to was used. A transparent silicone oil was used as the electrophoretic dispersion liquid 4.

Next, regarding the manufacturing method of the display device P ₁ ,
This will be described with reference to FIG.

When manufacturing the display device P ₁ , the first electrode 6 is formed on the entire surface of the one substrate 1b, and the electrode 6 is formed.
An insulating layer 8 was formed on the surface of the (see FIG. 3 (a)). Further, a TiC film is formed on the surface of the insulating layer 8 so that each pixel 2
70% of each of the above was removed by patterning to form the second electrode 7 in a dot shape (see FIG. 2B). Then, the electrode protective layer 9 was formed on the surface of the second electrode 7, and the partition walls 3 were pattern-formed on the surface thereof (see FIG. 3C).

Next, the suction drum (suction member) shown in FIG.
22B and the adsorption electrode 21 were used to spray the charged electrophoretic particles 5 to each pixel 2 in equal amounts (see FIG. 3D). At the time of the spraying, the adsorption drum 22B is uniformly charged and then laser light is irradiated to form an electrostatic latent image, and the electrophoretic particles 5 are attached to the surface of the adsorption drum 22B. While rotating and driving, the substrate 1a or 1b was moved in the plane direction.

Thereafter, a voltage of 70 V is applied between the first electrode 6 and the second electrode 7 to electrostatically adsorb the charged electrophoretic particles 5 to the respective pixels 2, and the electrophoretic dispersion liquid 4 is applied to each of them. It was injected into the pixel 2 (see FIG. 2E), and the substrates 1a and 1b were bonded together using the adhesive 19 while the voltage was applied (see FIG. 2F).

The display device P ₁ created as described above
Was driven by applying a voltage difference of 40 V to the electrodes 6 and 7, the contrast was 5 and the response speed was 20 mse.
A good indication of c was obtained. Since the charged electrophoretic particles 5 are negatively charged, when a negative voltage is applied to the second electrode 7 and a positive voltage is applied to the first electrode 6 as shown in FIG. The charged electrophoretic particles 5 gather on the portion where the first electrode 6 is exposed. In this embodiment,
Since the second electrode 7 and the charged electrophoretic particles 5 are both black,
A black display will be performed. Further, when a voltage of opposite polarity is applied to both electrodes, the charged electrophoretic particles gather on the second electrode 7 and white display is performed.

Further, no variation in density between the pixels was observed, and the display quality was good.

Example 2 In this example, the display device P ₁ shown in FIG. 1 was manufactured by the method shown in FIG.

That is, as in the first embodiment, first, the first
Electrode 6, insulating layer 8, second electrode 7, electrode protective layer 9, partition 3
Was formed on one substrate 1b (see FIG. 4 (a)).

Next, the suction plate 22 (A) as a suction member
Are uniformly charged and then a laser beam is irradiated to form an electrostatic latent image, the charged electrophoretic particles 5 are attached to the surface of the adsorption plate 22 (A), and the adsorption plate 22 (A) is attached to the substrate 1b. They are placed at opposite positions (see (b) in the same figure), and then the electrophoretic particles 5 are charged.
Was made to fly to each pixel (refer to the same figure (c)).

Then, in the same manner as in Example 1, injection of the electrophoretic dispersion liquid 4 (see FIG. 3D) and bonding of the substrates 1a and 1b (see FIG. 2E) were performed.

According to this example, the same effect as that of Example 1 was obtained. Further, since the charged electrophoretic particles 5 fly to each pixel while the adsorption plate 22 (A) is stationary, the flying position of the charged electrophoretic particles 5 can be controlled with high accuracy, and the charged electrophoretic particles 5 can be moved to a portion other than the pixel. It is possible to prevent the charged electrophoretic particles 5 from adhering to each other.

Example 3 In this example, the display device P ₂ shown in FIG. 2 was manufactured by the method shown in FIG.

That is, as shown in FIG. 2, the first electrode 1
6 is formed on the entire surface of one substrate 1a, the second electrode 17 is formed in a dot shape for each pixel on the other substrate 1b, and the insulating layer 8 is formed on the surfaces of the electrodes 16 and 17, respectively. Further, the first electrode 16 is provided on the partition wall (partition member) 3.
At a position near the second electrode 17 and away from the through hole 3
a is formed so that each pixel 2 is communicated. The size of the through hole 3a is set so that only the electrophoretic dispersion liquid 4 can move from the pixel 2 to another pixel 2 and the charged electrophoretic particles 5 cannot move.

For the substrates 1a and 1b, polyether sulfone (PES) having a gas barrier layer was used, ITO was used for the first electrode 16, and Ti was used for the second electrode 17.
Was used. Acrylic resin was used for the insulating layer 8 and polyimide resin was used for the partition walls 3. Further, as the charged electrophoretic particles 5, white particles (particle diameter 3 μm) in which titanium oxide particles are coated with a polymer containing a charge control agent and which are positively charged are used. A silicone oil colored blue with a blue pigment was used.

Next, regarding the manufacturing method of the display device P ₂ ,
This will be described with reference to FIG.

When manufacturing the display device P ₂ , the first electrode 16 is formed on the entire surface of the one substrate 1a (see FIG.
(See (a)), and the insulating layer 8 was formed on the surface of the electrode 16. Further, on the surface thereof, a through hole forming resist pattern 18 is formed in a line shape from the substrate end portion to the substrate end portion,
Further, the partition wall 3 was patterned so as to cover the resist pattern 18. After that, the through hole forming resist pattern 18 was dissolved and removed, and the through holes 3a were formed in the partition walls 3 (see FIG. 2B).

Next, the second electrode 1 is formed on the surface of the other substrate 1b.
7 was patterned, and an insulating layer 8 was formed on the surface (not shown).

Next, the charged electrophoretic particles 5 were dispersed on the substrate 1b by the same method as in Example 2 so that the dispersed amount of each pixel 2 formed later was almost equal (FIG. 3 (c)).
(See (d)).

After that, these substrates 1a and 1b were bonded together using an adhesive 19 (see FIG. 6 (e)).

It should be noted that the adhesive 19 has openings (not shown) provided at several positions apart from each other, and the air remaining in the substrate gap is sucked through the openings to reduce the pressure. The electrophoretic dispersion liquid 4 was injected from the opening (Fig. (F)).
reference). As a result, the electrophoretic dispersion liquid 4 is filled in each pixel 2 through the through hole 3a. At this time, the second electrode 17
A voltage is applied to the charged electrophoretic particles 5 so that the charged electrophoretic particles 5 are attracted to a position apart from the through holes 3a.
To prevent the injection of the electrophoretic dispersion liquid 4 from being blocked. Then, the opening of the adhesive 19 was sealed.

In the display device P ₂ thus produced, the first electrode 16 is grounded to the reference potential, and the second electrode 1
A positive or negative voltage was selectively applied to No. 7. When a negative voltage is applied to the second electrode 17, the positively charged charged electrophoretic particles 5 gather to cover the second electrode 17 as shown in FIG. In this case, when the display device P ₂ is viewed from the direction of the arrow A in the figure, only the electrophoretic dispersion liquid 4 colored in blue is visually recognized, the charged electrophoretic particles 5 are not visually recognized, and blue display is performed. . Also, the second
When a positive voltage is applied to the electrode 17, the positively charged charged electrophoretic particles 5 are separated from the second electrode 17 and gather on the side of the first electrode 16. In this case, when viewing the display device P ₂ from the direction of the arrow A shown in the figure, only the charged electrophoretic particles 5 colored in white are visually recognized, and the electrophoretic dispersion liquid 4 is not visually recognized, and white display is performed. .

When the inventor actually applied a voltage of 70 V to drive the display device P ₂ , a good display with a contrast of 4 and a response speed of 200 msec was obtained. Further, no density variation among the pixels was observed, and the display quality was good.

[0071]

As described above, according to the present invention,
Since the charged electrophoretic particles are arranged in substantially equal amounts in each pixel, the densities of the colors displayed by the particles are also substantially equal in each pixel, and the display quality of the produced display device is good.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of the configuration of a display device manufactured by the present invention.

FIG. 2 is a cross-sectional view showing another example of the configuration of the display device manufactured by the present invention.

FIG. 3 is a schematic view showing an example of a method of manufacturing a display device according to the present invention.

FIG. 4 is a schematic view showing another example of the method for manufacturing the display device according to the present invention.

FIG. 5 is a schematic view showing still another example of the method for manufacturing the display device according to the present invention.

FIG. 6 is a diagram for explaining a process and a device for spraying charged electrophoretic particles.

FIG. 7 is a diagram for explaining a process and a device for spraying charged electrophoretic particles.

FIG. 8 is a diagram showing a structure and an operating principle of an electrophoretic display device.

[Explanation of symbols]

1a, 1b Substrate 2 Pixel 3 Partition (partition member) 4 Dispersion liquid 5 Electrophoretic particles 6 First electrode 7 Second electrode 16 First electrode 17 Second electrode 21 Adsorption electrode 22 (A) Adsorption plate (adsorption member) 22 (B) Suction drum (suction member) P ₁ display device P ₂ display device

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Claims (7)

(57) [Claims] 1. A pair of substrates arranged with a predetermined gap therebetween, a partition member arranged so as to divide the predetermined gap into a plurality of pixels along the surface of the substrate, and the plurality of pixels. From the electrophoretic dispersion liquid and a large number of charged electrophoretic particles, and the first electrode and the second electrode respectively arranged in each pixel so as to face the electrophoretic dispersion liquid and the electrophoretic migration particles. In the method of manufacturing a display device for manufacturing the display device, one of the pair of substrates before the adsorption member that temporarily adsorbs the charged electrophoretic particles is placed with a predetermined gap therebetween. and disposed in a position facing the, then, causes attach the electrophoretic particles on the one substrate from the suction member, a method of manufacturing a display device, characterized in that. 2. The adsorption of the charged electrophoretic particles on the adsorption member is performed at a position corresponding to a pixel of the display device, and the arrangement of the adsorption member with respect to the one substrate is the electrostatic migration on the adsorption member. The method for manufacturing a display device according to claim 1, wherein the process is performed so that the portion where the particles are adsorbed faces the pixel of the display device. 3. The charging member is uniformly charged, and is partially discharged by irradiating with light, and the charged electrophoretic particles are adsorbed to a part of the adsorption member which is not discharged. The method for manufacturing a display device according to claim 2. 4. The display according to claim 3, wherein the adsorption amount per unit area of the charged electrophoretic particles adsorbed on the adsorption member is controlled by controlling the electrification amount of the adsorption member. Device manufacturing method. 5. Prior to adhering the charged electrophoretic particles from the adsorption member to the one substrate, at least one electrode of the first electrode and the second electrode and the partition member are formed on the one substrate. And attach the charged electrophoretic particles from the adsorption member to the one substrate .
After allowed to wear, the electrophoretic particles in each pixel by applying a voltage to electrodes formed on the substrate of the one while being electrostatically attracted, performs the arrangement of each pixel of the dispersion liquid, The method for manufacturing a display device according to claim 1, wherein the method is for manufacturing a display device. 6. Attaching the charged electrophoretic particles to the one substrate
The attachment is performed by using the flight of the charged electrophoretic particles by the electric field.
Uh, The method according to any one of claims 1 to 5, characterized in that
Of manufacturing display device of the above. 7. Attaching the charged electrophoretic particles to the one substrate
Adhesion is from the adsorption member to the one substrate
By transcribing the child, The method according to any one of claims 1 to 6, characterized in that
Of manufacturing display device of the above.