JP2009205002A - Electrophoretic display sheet, electrophoretic display device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophoretic display sheet, an electrophoretic display device and electronic equipment for exhibiting excellent color display properties. <P>SOLUTION: The electrophoretic display device 1 includes: capsules 6 filled with a dispersion medium 7 having first particles (A) and second particles (B) in different colors dispersed therein; cells 31 rotatably housing the capsules 6; an upper electrode 41 having electrode pieces 411, 412 disposed in one side via the cell 31 and a lower electrode 42 having electrode pieces 421, 422 disposed in the other side; an alternating current power supply 44 applying an alternating voltage between the electrodes; a moving means 4 moving the first particles (A) and the second particles (B) in the dispersion medium 7; and a rotating means 8 rotating the capsules 6. The dielectric constants of the first particles (A), the second particles (B) and the dispersion medium 7 denoted by ε1, ε2, ε3, respectively, satisfy a relationship of ε1>ε2>ε3. The capsule 6 has a transparent portion 622 to see the inside through the wall. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrophoretic display sheet, an electrophoretic display device, and an electronic apparatus.

For example, an electrophoretic display using particle electrophoresis is known as an image display unit of electronic paper (see, for example, Patent Document 1). The electrophoretic display has excellent portability and power saving, and is particularly suitable as an image display unit of electronic paper.
Patent Document 1 discloses an electrophoretic display device that constitutes a pixel of an electrophoretic display. The electrophoretic display device includes a cell, and in the cell, a transparent insulating liquid, positively charged white electrophoretic particles (hereinafter simply referred to as “white particles”), and negatively charged black Electrophoretic particles (hereinafter simply referred to as “black particles”) are enclosed. Further, a transparent electrode is installed on one side of the cell, and a colored plate is installed on the other side. Furthermore, the 1st electrode and the 2nd electrode are provided on the colored plate (refer FIG. 3 of patent document 1).

Such an electrophoretic display device has a white color by applying a voltage between the transparent electrode and the first and second electrodes, or applying a voltage between the first electrode and the second electrode. The desired color is displayed by causing the particles and the black particles to migrate in the transparent insulating liquid, thereby causing the white particles and the black particles to be unevenly distributed at desired portions.
Here, in the electrophoretic display device of Patent Document 1, when a voltage is applied to the first electrode and the second electrode, for example, black particles are unevenly distributed in the vicinity of the first electrode, and white particles are in the vicinity of the second electrode. Is unevenly distributed.

  At this time, when the inside of the cell is visually recognized through the transparent electrode, the color plate has a larger area than the total area of the aggregate of white particles and the aggregate of black particles. It becomes. However, since the white particles and the black particles are unevenly distributed between the transparent electrode and the colored plate, the white particles and the black particles are affected, and the color purity of the colored plate is lowered. It becomes difficult to display colors.

JP 2005-31345 A

  An object of the present invention is to provide an electrophoretic display sheet, an electrophoretic display device, and an electronic apparatus that can exhibit excellent color display properties.

Such an object is achieved by the present invention described below.
The electrophoretic display sheet of the present invention includes a capsule in which an internal space is filled with a dispersion medium in which first particles and second particles having different colors are dispersed;
An accommodating portion for rotatably accommodating the capsule;
A first electrode and a second electrode which are arranged opposite to each other via the housing portion and have a plurality of electrode pieces, and AC power supply means for applying an AC voltage therebetween, the first particle and the first electrode Moving means for moving the two particles in the dispersion medium;
Rotating means for rotating the capsule,
When the dielectric constants of the first particles, the second particles, and the dispersion medium are ε1, ε2, and ε3, respectively, the relationship of ε1>ε3> ε2 is satisfied,
The capsule has a see-through portion that can be visually recognized through the wall portion.
Thereby, the electrophoretic display sheet which can exhibit the outstanding color display property can be provided.

In the electrophoretic display sheet of the present invention, the moving means selects the first electrode and the second electrode by applying an electrode piece to which the AC voltage is applied from the plurality of electrode pieces of the first electrode and the second electrode. Changing the region of the second electrode to which the AC voltage is applied, thereby giving a difference between the electric field strength near the first electrode and the electric field strength near the second electrode; It is preferable that the first particle and the second particle are moved using the difference in dielectric constant of the second particle.
Thereby, a non-uniform electric field can be generated between the first electrode and the second electrode with a relatively simple configuration. As a result, the first particles and the second particles can be moved more reliably and easily.

In the electrophoretic display sheet of the present invention, the capsule is rotated by the rotating device to determine the posture of the capsule, and the moving device is used to move the first electric field near the strong electric field portion where the alternating electric field strength is relatively large. It is preferable that the color in the accommodating part visually recognized through the first electrode is changed by moving the second particles in the vicinity of one particle and a weak electric field part having a relatively small intensity. .
Thereby, the color of the wall part of a capsule, the color of 1st particle | grains, and the color of 2nd particle | grains can be displayed, and the outstanding color display property can be exhibited.

In the electrophoretic display sheet of the present invention, the moving means has selection means for selecting an electrode piece to which the AC voltage is applied from the plurality of electrode pieces, and the first electrode and the It is preferable to change the region to which the voltage of the second electrode is applied.
Thereby, the area | region which applies the voltage of a 1st electrode and a 2nd electrode with simple structure can be changed easily.

In the electrophoretic display sheet of the present invention, each of the first electrode and the second electrode includes a central electrode piece and a peripheral electrode piece provided so as to surround the periphery of the central electrode piece as the plurality of electrode pieces. It is preferable to have.
As a result, a non-uniform AC electric field that acts on the capsule can be generated with a relatively simple configuration, and the first particles can be unevenly distributed near the center of the housing portion, thereby improving the color display characteristics. .

In the electrophoretic display sheet of the present invention, the moving means applies an alternating voltage between the central electrode piece of the first electrode and the central electrode piece and the peripheral electrode piece of the second electrode piece; It is preferable that an AC voltage can be applied between the central electrode piece and the peripheral electrode piece of the first electrode and the central electrode piece of the second electrode piece.
Thereby, a difference can be given between the intensity near the first electrode and the intensity near the second electrode of the electric field generated between the first electrode and the second electrode relatively easily.

In the electrophoretic display sheet of the present invention, it is preferable that the container is filled with a liquid together with the capsule, and the capsule is floating.
Thereby, a capsule can be easily rotated within an accommodating part.
In the electrophoretic display sheet of the present invention, the capsule preferably has a substantially spherical shape.
Thereby, a capsule can be smoothly rotated within an accommodating part.

In the electrophoretic display sheet of the present invention, it is preferable that the fluoroscopic part is substantially colorless and transparent.
Thereby, the color of the 1st particle and the 2nd particle can be displayed as a display color more clearly.
In the electrophoretic display sheet of the present invention, it is preferable that the capsule has a colored portion in a portion different from the see-through portion.
Thereby, in addition to the colors of the first particles and the second particles, the color of the colored portion can be displayed as the display color, so that the display characteristics are improved.

In the electrophoretic display sheet of the present invention, it is preferable that the capsule has an intermediate color portion that forms an intermediate color between the fluoroscopic portion and the coloring portion.
Thereby, gradation expression of the color of the colored portion is possible, and the display characteristics of the electrophoretic display sheet are further improved.
In the electrophoretic display sheet of the present invention, the capsule has a positively charged positively charged region and a negatively charged negatively charged region,
The rotating means is preferably configured to rotate the capsule by applying an electric field or a magnetic field to the capsule.
Thus, by applying an electric field to the capsule, the capsule can be rotated, and the posture of the capsule can be determined easily and reliably.

In the electrophoretic display sheet of the present invention, it is preferable that one of the positively charged region and the negatively charged region is located in the see-through portion and the other is located in the colored portion.
Thereby, it can be set as the state (posture) where the coloring part is located on the first electrode side and the state (posture) where the fluoroscopic part is located on the first electrode side easily and reliably. As a result, the operation of the electrophoretic display device becomes easy.

In the electrophoretic display sheet of the present invention, the rotating means includes a pair of capsule rotating electrodes disposed opposite to each other via the housing portion, and a DC power source means for applying a DC voltage between the pair of capsule rotating electrodes. Preferably, the capsule is rotated by applying a DC voltage between the pair of capsule rotating electrodes by the action of the DC power supply means.
Thereby, the capsule can be rotated with a relatively simple configuration, and the posture of the capsule can be determined.

In the electrophoretic display sheet of the present invention, it is preferable that the first electrode and the second electrode also serve as the pair of capsule rotation electrodes.
As a result, it is possible to reduce the size of the apparatus, reduce costs, and facilitate manufacturing.
In the electrophoretic display sheet of the present invention, the AC voltage for moving the first particles and the second particles and the DC voltage for rotating the capsule are superimposed to overlap the first electrode and the first electrode. It is preferable to be configured to apply between two electrodes.
Thereby, since rotation of a capsule and movement (dielectric migration) of a 1st particle and a 2nd particle can be performed simultaneously, switching of a display color can be performed rapidly.

In the electrophoretic display sheet of the present invention, by setting a voltage application pattern to the first electrode and the second electrode, the first state in which the colored portion of the capsule is located on the first electrode side; A second state in which the see-through portion of the capsule is located on the first electrode side and the first particles are unevenly distributed on the first electrode side in the capsule; and the see-through portion of the capsule is the first It is preferable that the second particle can be selected from a third state located on the electrode side and located on the first electrode side in the capsule.
Thereby, while setting it as a comparatively simple structure, the color of the wall part of a capsule, the color of a 1st particle, and the color of a 2nd particle can be displayed, and the outstanding color display property can be exhibited. .

The electrophoretic display device of the present invention includes the electrophoretic display sheet of the present invention and a substrate provided on the second electrode side of the housing portion.
Thereby, an electrophoretic display device capable of exhibiting excellent color display properties can be provided.
An electronic apparatus according to the present invention includes the electrophoretic display device according to the present invention.
Thereby, the electronic device which can exhibit the outstanding color display property can be provided.

Hereinafter, an electrophoretic display sheet, an electrophoretic display device, and an electronic apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Electrophoretic display device>
<< First Embodiment >>
First, a first embodiment of an electrophoretic display device (electrophoretic display device of the present invention) to which the electrophoretic display sheet of the present invention is applied will be described.

FIG. 1 is a schematic longitudinal sectional view showing a first embodiment of the electrophoretic display device of the present invention, FIG. 2 is a diagram showing rotating means and moving means provided in the electrophoretic display device shown in FIG. FIG. 8 is a schematic longitudinal sectional view showing the operation of the electrophoretic display device shown in FIG. In the following, for convenience of explanation, the upper side of FIGS. 1 and 3 to 8 is referred to as “upper” and the lower side is referred to as “lower”.
An electrophoretic display device 1 shown in FIG. 1 includes a circuit board (back plane) 9 and an electrophoretic display sheet 2 bonded to the upper surface of the circuit board 9.
The circuit board 9 includes a flat base 91 and a circuit (not shown) including a switching element such as a TFT provided on the base 91.

On the other hand, the electrophoretic display sheet 2 is provided on the base 3 having a plurality of cells (accommodating portions) 31, capsules (microcapsules) 6 accommodated in the cells 31 together with the dielectric liquid 5, and the upper surface of the base 3. A plurality of upper electrodes (first electrodes) 41 and a plurality of lower electrodes 42 (second electrodes) provided on the lower surface of the substrate 3 are provided.
The internal space 61 of the capsule 6 is filled with a dispersion medium 7 in which first particles A and second particles B having different colors are dispersed.

The upper electrode 41 includes a central electrode piece 412 and a peripheral electrode piece 411 provided so as to surround the periphery thereof. Similarly, the lower electrode 42 also includes the central electrode piece 422 and the peripheral electrode piece. 421. Hereinafter, for convenience of explanation, the central electrode piece and the peripheral electrode piece are also simply referred to as electrode pieces, respectively.
Such four electrode pieces 411, 412, 421, 422 are electrically connected to the DC power supply 83 and the AC power supply 44 via the selection means 43 including, for example, a switching element.

  In such an electrophoretic display device 1, a voltage is applied by a DC power supply 83 or an AC power supply 44 between a plurality of electrode pieces selected by the selection means 43 from the four electrode pieces 411, 412, 421, and 422. Thus, the capsule 6 is rotated in the cell 31 or the first particle A and the second particle B are moved in the capsule 6 to change the color in the cell 31 that is visually recognized through the upper electrode 41. It is configured to Hereinafter, for convenience of explanation, the color in the cell 31 visually recognized through the upper electrode 41 is referred to as “display color”.

In the present embodiment, the upper electrode 41, the lower electrode 42, the selection means 43 and the AC power supply 44 constitute the moving means 4 for moving the first particles A and the second particles B in the dispersion medium 7, and the upper electrode 41, The lower electrode 42, the selection unit 43, and the DC power source 83 constitute a rotation unit 8 that rotates the capsule 6 within the cell 31.
That is, in this embodiment, the upper electrode 41 and the lower electrode 42 constitute a part of the moving means 4 and a part of the rotating means 8. Thereby, it is possible to reduce the size of the image display device 1 and to reduce the cost and facilitate the manufacture.

Hereinafter, although each configuration will be described in detail, in the electrophoretic display device 1, the portions corresponding to the respective cells 31 each constitute one pixel, and the plurality of pixels have the same configuration as each other. Hereinafter, for convenience of description, one pixel P will be described as a representative, and description of other pixels will be omitted.
The substrate 3 may be either flexible or hard, but is preferably flexible. Use of the substrate 3 having flexibility is advantageous in constructing the electrophoretic display device 1 having flexibility, that is, for example, electronic paper.

The substrate 3 is substantially colorless and transparent, and the inside of the cell 31 can be visually recognized from the outside of the substrate 3. Further, the thickness of the substrate 3 is not particularly limited, but is preferably about 10 to 500 μm, and more preferably about 20 to 100 μm.
Examples of the constituent material of the substrate 3 include various resin materials such as epoxy resins, acrylic resins, urethane resins, melamine resins, and phenol resins, polyethylene, polypropylene, and ethylene-vinyl acetate copolymers. Such as polyolefin, modified polyolefin, polyamide (eg, nylon 6, nylon 66), various thermoplastic elastomers such as styrene, polyvinyl chloride, polyurethane, polyester, fluororubber, chlorinated polyethylene, etc. And a copolymer, a blend, a polymer alloy, and the like. Among these, one or two or more of these can be mixed and used.

The cell 31 has a substantially spherical shape. The shape of the cell 31 is not particularly limited as long as the capsule 6 can be rotatably accommodated. For example, the cell 31 may have a cylindrical shape or a rectangular parallelepiped shape.
Examples of the dielectric liquid 5 filled in the cell 31 include aromatic hydrocarbons such as benzene and toluene, alicyclic hydrocarbons such as cyclohexane, isoparaffins such as Isopar G and Isopar L, dimethyl silicone oil, methyl Examples include silicone oils such as phenyl silicone oil and methyl hydrogen silicone oil, and these can be used alone or as a mixture.

The cell 31 contains a capsule 6 together with such a dielectric liquid 5. As a result, the capsule 6 floats in the dielectric liquid 5 in the cell 31 and can be rotated in the cell 31. With such a configuration, as described later, the capsule 6 can be easily rotated by applying a specific voltage between the upper electrode 41 and the lower electrode 42.
The capsule 6 has a substantially spherical shape. Therefore, the capsule 6 can be smoothly rotated in the cell 31.

Such a capsule 6 has a substantially spherical shell (wall portion) 62 that defines an internal space 61. The shell 62 includes a substantially colorless and transparent see-through portion 622 in which the inside (inner space 61) can be visually recognized through the shell 62, a colored portion 621, and a portion between the see-through portion 622 and the color portion 621. And an intermediate color portion 623 that forms an intermediate color between them.
In the present embodiment, when the shell 62 is divided into two hemispherical regions, the see-through portion 622 is formed in one hemispherical region, and the colored portion 621 and the intermediate color portion 623 are formed in the other hemispherical region.

  As described above, since the shell 62 has the see-through portion 622, the first particles A and the second particles B in the internal space 61 can be visually recognized from the outside of the capsule 6. As a result, the colors of the first particles A and the second particles can be displayed as display colors. In particular, in this embodiment, since the see-through | perspective part 622 is colorless and transparent, the color of the 1st particle | grain A and the 2nd particle | grain B can be displayed as a display color more clearly.

Further, since the shell 62 includes the coloring portion 621, the color of the coloring portion 621 can be displayed as a display color. Thereby, in addition to the color of the 1st particle A and the 2nd particle B, since the color of the coloring part 621 can be displayed as a display color, a color display characteristic improves.
The color of the coloring unit 621 can be arbitrarily selected from achromatic colors such as white, black, and gray, and chromatic colors such as red, blue, and green. Among these, it is preferable that the color of the colored portion 621 is a chromatic color. Thereby, the electrophoretic display device 1 can perform color display.

Further, since the shell 62 includes the intermediate color portion 623, an intermediate color between the coloring portion 621 and the fluoroscopic portion 622 can be displayed as a display color. That is, color gradation expression of the coloring unit 621 is possible, and the color display characteristics of the electrophoretic display device 1 are further improved.
In particular, since the intermediate color portion 621 of the present embodiment has a gradation that continuously changes from the color of the coloring portion 621 to the transparent portion 622 from the coloring portion 621 side to the see-through portion 622 side, The gradation of the color can be made more multi-gradation.

The shell 62 has a positively charged area and a negatively charged area charged to opposite polarities. Thereby, by applying a desired voltage between the upper electrode 41 and the lower electrode 42 and applying an electric field to the capsule 6, the capsule 6 can be rotated easily and reliably, and the posture of the capsule 6 is determined. can do.
In the present embodiment, the colored portion 621 is a positively charged region, and the fluoroscopic portion 622 is a negatively charged region. In this way, by positioning one of the positively charged region and the negatively charged region at the fluoroscopic part 622 and the other at the colored part 621, the colored part 621 can be easily and reliably placed on the upper electrode as will be described later. The state located on the 42 side and the state where the fluoroscopic part 622 is located on the upper electrode 41 side can be taken. Thereby, the operation of the electrophoretic display device 1 is facilitated.

  Examples of the constituent material of the shell 62 include resin materials such as gelatin, gelatin-gum arabic, gelatin-gellan gum, polystyrene, polymethyl methacrylate, polyester, polyphenyl ester, polyurethane, nylon 6, nylon 66, and polyurea. These can be used, and one or more of these can be used in combination.

As a method for forming such a shell 62, a coacervation method, a complex coacervation method, an interfacial polymerization method, a spray drying method, and various known methods can be used.
Examples of a method for forming the positively charged colored portion 621 include (i) a method of vacuum-depositing carbon black, copper phthalocyanine, titanyl phthalocyanine, ammonium, tungsten, and the like, and (ii) a resin in which a pigment or dye is dispersed. A method in which the capsule 6 is dispersed or dissolved in a solvent and applied by spray coating, dip coating, or a doctor blade, (iii) a method in which the capsule 6 is immersed in a solvent containing an oil-soluble disperse dye, and the shell 62 is impregnated. Is mentioned. The formation method of the intermediate color portion 623 is the same as the formation method of the coloring portion 621.

  For example, in the case of (ii), examples of the pigment include black pigments such as carbon black and magnetite, azo pigments such as soluble azo, monoazo, and disazo, polycyclic pigments such as phthalocyanine and quinacridone, And white pigments such as titanium dioxide, silicon dioxide, alumina, and calcium carbonate. Examples of the dye include oil-soluble dyes, reactive dyes, disperse dyes, direct dyes, acid dyes, and basic dyes. You may mix and use these pigments or dyes.

Examples of the resin for dispersing the pigment or dye include known resins used in commercially available colored sprays such as acrylic resins and alkyd resins. The colored portion 621 can be formed by dissolving a resin in which a pigment or dye is dispersed in an organic solvent such as toluene, butyl acetate, or ethyl acetate and applying the resin on the surface of the capsule 6.
Furthermore, in order to further charge the capsule 6, a charge control agent may be mixed in the resin together with a pigment and a dye. Specific examples of the charge control agent include positive charge control agents such as nigrosine dyes, triphenylmethane dyes, and quaternary ammonium salts.

On the other hand, as a method for forming the negatively charged fluoroscopic portion 622, there is a method in which (ii) mentioned in the method for forming the colored portion 621 is performed without using a pigment or a dye.
Specifically, for example, a negative charge control agent such as a salicylic acid compound or a boron compound is mixed in an acrylic resin or an alkyd resin, and this resin is dissolved in an organic solvent such as toluene, butyl acetate, or ethyl acetate. By applying to the surface of the capsule 6, the see-through part 622 can be formed.
Although the capsule 6 has been described above, the particle size of the capsule 6 is preferably 10 μm to 200 μm from the viewpoint of resolution, concealment rate, and the like.

Next, the dispersion medium (liquid phase dispersion medium) 7 filled in the internal space 61 of the capsule 6 will be described.
The dispersion medium 7 is preferably substantially colorless and transparent. As such a dispersion medium 7, a medium having a relatively high insulating property is preferably used. Examples of the dispersion medium 7 include various types of water (distilled water, pure water, ion-exchanged water, etc.), alcohols such as methanol, ethanol, and butanol, cellosolves such as methyl cellosolve, and esters such as methyl acetate and ethyl acetate. , Ketones such as acetone and methyl ethyl ketone, aliphatic hydrocarbons such as pentane, alicyclic hydrocarbons such as cyclohexane, and aromatic hydrocarbons such as benzene having a long-chain alkyl group such as benzene and toluene , Halogenated hydrocarbons such as methylene chloride and chloroform, aromatic heterocycles such as pyridine and pyrazine, nitriles such as acetonitrile and propionitrile, amides such as N, N-dimethylformamide, carboxylates, Mineral oils such as liquid paraffin, vegetable oils such as linoleic acid, linolenic acid and oleic acid, dimethyl silyl Silicone oils such as hydrogen oil, methylphenyl silicone oil, and methyl hydrogen silicone oil, fluorine-based liquids such as hydrofluoroether, and other various oils, and other various oils. It can be used alone or as a mixture.

Further, in the dispersion medium 7, for example, a charge control agent composed of particles of electrolyte, surfactant, metal soap, resin material, rubber material, oils, varnish, compound, etc., titanium coupling, if necessary. You may make it add various additives, such as dispersing agents, lubricants, stabilizers, such as an agent, an aluminum coupling agent, and a silane coupling agent.
As described above, the first particles A and the second particles B are dispersed in the dispersion medium 7.

The first particles A and the second particles B have different colors. The color (color) of the first particle A and the second particle B is not particularly limited, and two colors are arbitrarily selected from achromatic colors such as white, black, and gray, and chromatic colors such as red, blue, and green. Can be selected. In the present embodiment, the first particles A are white particles, and the second particles B are black particles.
The first particles A and the second particles B have different dielectric constants. Specifically, the dielectric constants of the first particles A, the second particles B, and the dispersion medium 7 are ε1, ε2, and ε3, respectively. Then, the relationship of ε1>ε3> ε2 is satisfied.

  By satisfying such a relationship, when a non-uniform electric field is applied to the first particle A and the second particle B from the outside, the first particle A having a higher dielectric constant than the dispersion medium 7 has a higher electric field strength. On the contrary, the second particles B having a dielectric constant smaller than that of the dispersion medium 7 receive a repulsive force from a region having a high electric field strength. As a result, the first particles A are guided to a region having a strong electric field strength, and the second particles B are guided to a region having a weak electric field strength. Such a phenomenon is called “dielectrophoresis”, and the present invention is configured to move the first particles A and the second particles B using this dielectrophoresis to change the display color. In addition, when a uniform electric field is applied to the first particles A and the second particles B, the above-described dielectrophoresis does not occur.

  As the first particles A and the second particles B, any particles can be used as long as they satisfy the conditions described above, and are not particularly limited, but pigment particles, resin particles, At least one of ceramic particles, metal particles, metal oxide particles, or composite particles thereof is preferably used. These particles have the advantage that they are easy to manufacture and the charge can be controlled relatively easily.

  Examples of pigments constituting the pigment particles include black pigments such as aniline black, carbon black, and titanium black, white pigments such as titanium dioxide, antimony trioxide, zinc sulfide, and zinc white, and azo series such as monoazo, disazo, and polyazo. Pigments, yellow pigments such as isoindolinone, yellow lead, yellow iron oxide, cadmium red and titanium red, azo pigments such as monoazo, disazo and polyazo, red pigments such as quinacridone red and chrome vermillion, phthalocyanine blue and indanthrene Blue pigments such as blue, bitumen, ultramarine, and cobalt blue, green pigments such as phthalocyanine green, and the like can be used, and one or more of these can be used in combination.

Examples of the resin material constituting the resin particles include acrylic resin, urethane resin, urea resin, epoxy resin, rosin resin, polystyrene, polyester, AS resin copolymerized with styrene and acrylonitrile, and the like. These can be used alone or in combination of two or more.
The composite particles are, for example, composed of pigment particles whose surfaces are coated with a resin material, resin particles whose surfaces are coated with a pigment, or a mixture of a pigment and a resin material mixed in an appropriate composition ratio. Particles and the like.

Moreover, the average particle diameter of the 1st particle | grains A and the 2nd particle | grains B is although it does not specifically limit, It is preferable that it is about 0.1-10 micrometers, and it is more preferable that it is about 0.1-7.5 micrometers. If the average particle diameter of the particles is too small, a sufficient concealment rate cannot be obtained mainly in the visible light range, and as a result, the display contrast of the electrophoretic display device 1 may be lowered. If the particle size is too large, depending on the type or the like, it tends to settle in the dispersion medium 7, which may cause problems such as deterioration in display quality of the electrophoretic display device 1.
Although the first particle A and the second particle B have been described above, the dispersion of the two particles A and B in the dispersion medium 7 can be performed by, for example, the paint shaker method, the ball mill method, the media mill method, or the ultrasonic dispersion. The method can be carried out by combining one or more of the methods, stirring and dispersing methods and the like.

Next, the upper electrode 41 and the lower electrode 42 will be described.
The upper electrode 41 and the lower electrode 42 are opposed to each other with the cell 31 interposed therebetween. Further, as described above, the upper electrode 41 is constituted by the peripheral electrode piece 411 and the central electrode piece 412, and the lower electrode 42 is constituted by the peripheral electrode piece 421 and the central electrode piece 422.
By adopting such a configuration for the upper electrode 41 and the lower electrode 42, the regions to which the voltages of the upper electrode 41 and the lower electrode 42 are applied can be easily changed, and the upper electrode 41 can be reliably configured with a simple configuration. And the lower electrode 42 can generate a non-uniform alternating electric field (that is, an electric field that produces a difference between the electric field strength near the upper electrode 41 and the electric field strength near the lower electrode 42).

Specifically, if an AC voltage is applied between the central electrode piece 412, the peripheral electrode piece 421 and the central electrode piece 422, the upper electrode with respect to the capsule 6 is interposed between the upper electrode 41 and the lower electrode 42. It is possible to generate a non-uniform AC electric field in which the 41 side is a strong electric field part and the lower electrode 42 side is a weak electric field part.
Conversely, if an AC voltage is applied between the central electrode piece 412 and the peripheral electrode piece 411 and the central electrode piece 422, the upper electrode 41 side is located between the upper electrode 41 and the lower electrode 42 with respect to the capsule 6. A non-uniform AC electric field in which the weak electric field part and the lower electrode 42 side become a strong electric field part can be generated.

In particular, as in the present embodiment, when the upper electrode 41 and the lower electrode 42 are respectively composed of the central electrode pieces 412, 422 and the peripheral electrode pieces 411, 421 provided so as to surround the periphery thereof, the upper electrode 41 and the lower electrode 42 are formed. The AC electric field generated between the electrode 42 and the electrode 42 can be efficiently applied to the first particle A and the second particle B.
As the central electrode piece 412 and the peripheral electrode piece 411, for example, <1> the central electrode piece 412 may have a disk-like cross shape, and the peripheral electrode piece 411 may surround the central electrode piece 412. <2> The center electrode piece 412 may have a longitudinal shape, and a pair of peripheral electrode pieces 411 may be provided so as to oppose each other via the center electrode piece 412. The same applies to the center electrode piece 422 and the peripheral electrode piece 421.

The upper electrode 41 (the central electrode piece 412 and the peripheral electrode piece 411) is substantially colorless and transparent. Thereby, the inside of the cell 31 can be visually recognized through the upper electrode 41 from the outside of the electrophoretic display device 1. The upper electrode 41 may not be colorless and transparent as long as the inside of the cell 31 can be visually recognized from the outside of the electrophoretic display device 1 and may be colored.
The upper electrode 41 (the central electrode piece 412 and the peripheral electrode piece 411) is substantially colorless and transparent. Thereby, the inside of the cell 31 can be visually recognized through the upper electrode 41 from the outside of the electrophoretic display device 1. The upper electrode 41 may not be colorless and transparent as long as the inside of the cell 31 can be visually recognized from the outside of the electrophoretic display device 1 and may be colored.

In addition, the constituent material of the upper electrode 41 (the annular electrode piece 411 and the central electrode piece 412) is not particularly limited as long as it is substantially conductive, and examples thereof include copper, aluminum, and alloys containing these. In metal materials, carbon-based materials such as carbon black, electronic conductive polymer materials such as polyacetylene, polypyrrole, or derivatives thereof, and matrix resins such as polyvinyl alcohol, polycarbonate, and polyethylene oxide, NaCl, LiClO ₄ , KCl, LiBr , Ion conductive polymer material in which ionic substances such as LiNO ₃ and LiSCN are dispersed, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), tin oxide (SnO ₂ ), indium oxide Various conductive materials such as conductive oxide materials such as (IO) It can be used singly or in combination of two or more of them.
The lower electrode 42 may be opaque or transparent. The constituent material of the lower electrode 42 is not particularly limited as long as it is substantially conductive, and the same material as the constituent material of the upper electrode 41 described above can be used.

  Next, the operation of the electrophoretic display device 1 will be described with reference to FIGS. 1 and 3 to 8. 1 and 3 to 8 are schematically illustrated for convenience of explanation, and it goes without saying that the numbers and sizes of the first particles A and the second particles B are greatly different from actual ones. Yes. Hereinafter, for convenience of explanation, the central electrode piece and the peripheral electrode piece are also simply referred to as “electrode pieces”. In addition, the color of the coloring unit 621 is red.

<1> Red Display First, the red display state (first state) will be described.
The selection means 43 selects all the electrode pieces 411, 412, 421, and 422 as electrode pieces to which a voltage is applied. Next, the electrode pieces 411 and 412 are negative and the electrode pieces 421 and 422 are positive between the electrode pieces 411 and 412 (upper electrode 41) and the electrode pieces 421 and 422 (lower electrode 42) by the DC power supply 83. A DC voltage such as this is applied.

When such a DC voltage is applied, the capsule 6 rotates so that the colored portion 621 faces the upper electrode 41 and the see-through portion 622 faces the lower electrode 42, and the colored portion 621 moves to the upper electrode 41 as shown in FIG. 3. The posture (state) is located on the side. In this state, since the colored portion 621 is confirmed when the cell 31 is visually recognized through the upper electrode 41, red is visually recognized as the display color.
Note that when the DC voltage is applied, a uniform electric field, that is, an electric field having substantially the same intensity in the entire region, is generated between the upper electrode 41 and the lower electrode 42. Even if such an electric field acts on the first particles A and the second particles B in the dispersion medium 7, the first particles A and the second particles B do not undergo dielectrophoresis and remain as they are (that is, in the dispersion medium 7. Maintain a uniform distribution).

<2> White Display Next, the white display state (second state) will be described. The selection means 43 selects all the electrode pieces 411, 412, 421, 422 as electrode pieces to which a voltage is applied. Next, the DC power source 83 causes the electrode pieces 411 and 412 to be positive and the electrode pieces 421 and 422 to be negative between the electrode pieces 411 and 412 (upper electrode 41) and the electrode pieces 421 and 422 (lower electrode 42). A DC voltage such as this is applied.

  When such a DC voltage is applied, the capsule 6 rotates so that the coloring portion 621 faces the lower electrode 42 and the see-through portion 622 faces the upper electrode 41, and the see-through portion 622 becomes the upper electrode 41 as shown in FIG. 4. The posture (state) is located on the side. As a result, when the cell 31 is viewed through the upper electrode 41, the internal space 61 of the shell 62 can be viewed through the see-through portion 622.

  In this state, the voltage application by the DC power supply 83 is stopped, and the selection means 43 selects the electrode pieces 412, 421, 422 as the electrode pieces to which the voltage is applied (that is, no voltage is applied to the peripheral electrode pieces 411). . Next, an AC voltage is applied between the central electrode piece 412, the peripheral electrode piece 421, and the central electrode piece 422 by the AC power supply 44. As a result, an AC electric field H 1 as shown in FIG. 5 is generated between the upper electrode 41 and the lower electrode 42.

The AC electric field H1 shown in FIG. 5 has a strong electric field portion H11 having a relatively strong electric field strength on the upper side (upper electrode 41 side), and a weak electric field having a relatively weak electric field strength on the lower side (lower electrode 42 side). Part H12. Therefore, the first particles A having a dielectric constant larger than that of the dispersion medium 7 are dielectrophoresed toward the upper electrode 41 so as to be adsorbed to the strong electric field portion H11, and the second particles B having a dielectric constant smaller than that of the dispersion medium 7 are obtained. Is dielectrophoresed toward the lower electrode 42 so as to be attracted to the weak electric field portion H12.
As a result, as shown in FIG. 5, in the capsule 6, the first particles A are unevenly distributed in the part corresponding to the fluoroscopic part 622, and the second particles B are unevenly distributed in the part corresponding to the colored part 621. . Since the capsule 6 is not rotated by such an alternating electric field H1, white is visually recognized as the display color in this state.

The dielectric constants ε1, ε2, and ε3 of the first particle A, the second particle B, and the dispersion medium 7 have a predetermined correlation with the frequency of the AC electric field H1 (that is, the dielectric constant ε1). , Ε2 and ε3 each have frequency dependence). Therefore, the frequency of the AC electric field H1 must satisfy the above-described relationship of ε1>ε3> ε2. The frequency of the AC electric field H1 is preferably relatively high in order to effectively prevent the capsule 6 from rotating. As such a frequency, for example, 1 × 10 ² to 1 × 10 ⁹ [Hz] is preferable, 1 × 10 ² to 1 × 10 ⁶ [Hz] is more preferable, and 1 × 10 ^5. More preferably, it is ˜1 × 10 ⁶ [Hz]. The same applies to the frequency of the alternating electric field H2, which will be described later.

<3> Black Display Next, the black display state (third state) will be described.
First, the white display state described above is set. Next, the electrode pieces 411, 412, and 422 are selected by the selection means 43 as the electrode pieces to which a voltage is applied (that is, no voltage is applied to the electrode pieces 421). Then, an AC voltage is applied between the electrode pieces 411 and 412 and the electrode piece 422 by the AC power supply 44. As a result, an alternating electric field H2 as shown in FIG. 6 is generated between the upper electrode 41 and the lower electrode.

  The AC electric field H2 shown in FIG. 6 has a strong electric field portion H21 having a relatively strong electric field strength on the lower side (lower electrode 42 side), and a weak electric field having a relatively weak electric field strength on the upper side (upper electrode 41 side). It has a portion H22. Accordingly, the first particles A having a dielectric constant larger than that of the dispersion medium 7 are dielectrophoresed toward the lower electrode 42 so as to be adsorbed to the strong electric field portion H21, and the second particles B having a dielectric constant smaller than that of the dispersion medium 7. Is dielectrophoresed toward the upper electrode 41 so as to be attracted to the weak electric field portion H22.

Thereby, as shown in FIG. 6, in the capsule 6, the second particles B are unevenly distributed in a portion corresponding to the fluoroscopic portion 622, and the first particles A are unevenly distributed in a portion corresponding to the colored portion 621. . Since the capsule 6 does not rotate by such an alternating electric field H2, black is visually recognized as the display color in this state.
Although the case where the see-through portion 622 of the capsule 6 is positioned on the upper electrode 41 side has been described above, the coloring portion 621 of the capsule 6 may be positioned on the upper electrode 41 side. According to this, it is possible to display a darker (sunk) black as compared with the case where the fluoroscopic part 622 is positioned on the upper electrode 41 side.

<4> Intermediate Color Display Next, the intermediate color display state will be described.
The capsule 6 is rotated by the operation described above, and the rotation of the capsule 6 is stopped when the intermediate color portion 623 is located on the upper electrode 41 side (that is, the voltage application to the electrode piece is stopped). As a result, the capsule 6 assumes the posture (state) shown in FIG.
In this state, for example, when the AC electric field H1 is generated by the operation described above, the white first particles A are unevenly distributed on the upper electrode 41 side as shown in FIG. Therefore, in this state, part of the light incident from the upper electrode 41 passes through the intermediate color portion 623 and is diffused by the first white particles A, so that an intermediate color of red and white is visually recognized.

On the other hand, when the AC electric field H2 is generated by the operation described above, the black second particles B are unevenly distributed on the upper electrode 41 side as shown in FIG. Therefore, in this state, a part of the light incident from the upper electrode 41 passes through the intermediate color portion 623 and is absorbed by the black second particles B, whereby an intermediate color between red and black is visually recognized.
As described above, since the capsule 6 has the intermediate color portion 623, it is possible to express the gradation of red and enrich the expression. In particular, in the present embodiment, since the intermediate color portion 623 has gradation, the effect becomes more prominent.
The operation of the electrophoresis table device 1 has been described in detail above.

  In the present embodiment, the first particles A are white particles and the second particles B are black particles, so that the reactivity of black and white display can be particularly improved. Specifically, switching between black display and white display does not involve rotation of the capsule 6, so that switching between the black display state and the white display state can be performed quickly, and the black-and-white display has excellent reactivity. Become. Such an effect is also exhibited when the first particles A are black particles and the second particles are white particles.

  In the present embodiment, since the color of the coloring portion 621 is a chromatic color, color display is possible while improving the black-and-white display reactivity as described above. As described above, the electrophoretic display device 1 has excellent colors by using the first particles A as black particles, the second particles B as white particles, and the color of the colored portion 621 of the capsule 6 as a chromatic color. Display characteristics can be exhibited.

<< Second Embodiment >>
Next, a second embodiment of the electrophoretic display device of the present invention will be described.
FIG. 9 is a schematic longitudinal sectional view showing a second embodiment of the electrophoretic display device of the present invention.
Hereinafter, the electrophoretic display device according to the second embodiment will be described with a focus on differences from the above-described embodiments, and description of similar matters will be omitted.
The electrophoretic display device according to the second embodiment of the present invention is the same as that of the first embodiment except that the rotating means for rotating the capsule and the moving means for moving the first particles A and the second particles B are simultaneously operated. The same as the electrophoretic display device. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above.

<1> Red Display First, the red display state will be described.
The selection means 43 selects electrode pieces 412, 421, 422 as electrode pieces to which a voltage is applied. Next, an AC voltage applied between the central electrode piece 412, the peripheral electrode piece 421 and the central electrode piece 422 is generated from the AC power supply 44. At the same time, a DC voltage is generated from the DC power source 83 such that the central electrode piece 412 is negative and the peripheral electrode piece 421 and the central electrode piece 422 are positive. The generated AC voltage and DC voltage are superimposed by the superimposing unit 100, and the superimposed voltage is applied between the central electrode piece 412, the peripheral electrode piece 421, and the central electrode piece 422.

  As a result, the capsule 6 rotates so that the colored portion 621 is positioned on the upper electrode 41 side, the first particles A dielectrophoresis toward the upper electrode 41 side, and the second particles B move toward the lower electrode 42 side. And dielectrophoresis. As a result, the colored portion 621 of the capsule 6 is positioned on the upper electrode 41 side, and the first particles A are positioned so as to correspond to the colored portion 621. In this state, red is visually recognized as the display color.

  In addition, when it is desired to reduce the brightness of red as compared with the above-described red display, the following may be performed. First, electrode pieces 411, 412, and 422 are selected as electrode pieces to which a voltage is applied. Next, an AC voltage applied between the peripheral electrode piece 411 and the central electrode piece 412 and the central electrode piece 422 is generated from the AC power supply 44. At the same time, a DC voltage is generated from the DC power source 83 such that the peripheral electrode piece 411 and the central electrode piece 412 are negative and the central electrode piece 422 is positive. The generated AC voltage and DC voltage are superimposed by the superimposing unit 100, and the superimposed voltage is applied between the central electrode piece 412, the peripheral electrode piece 421, and the central electrode piece 422.

  As a result, the capsule 6 rotates so that the colored portion 621 is positioned on the upper electrode 41 side, the second particles B dielectrophoresis toward the upper electrode 41 side, and the first particles A move toward the lower electrode 42 side. And dielectrophoresis. At this time, if the voltage application from the AC power supply 44 is stopped at the stage where the second particles B do not reach the colored portion 621, a red color with a lower brightness can be displayed as compared with the above-described red color display.

  That is, by controlling the separation distance between the coloring portion 621 (upper electrode 41) and the second particles B, it is possible to adjust the lightness of red. The method for controlling the separation distance between the colored portion 621 and the second particles B is not particularly limited, but for example, the frequency of the AC voltage generated from the AC power supply 44, the amplitude, or the application time can be controlled. It is effective to control. Note that when the second particles B reach the colored portion 621, the display color becomes black as described later.

<2> White display Next, the white display state will be described.
The selection means 43 selects electrode pieces 412, 421, 422 as electrode pieces to which a voltage is applied. Next, an AC voltage applied between the central electrode piece 412, the peripheral electrode piece 421 and the central electrode piece 422 is generated from the AC power supply 44. At the same time, a DC voltage is generated from the DC power source 83 such that the central electrode piece 412 is positive and the peripheral electrode piece 421 and the central electrode piece 422 are negative. The generated AC voltage and DC voltage are superimposed by the superimposing unit 100, and the superimposed voltage is applied between the central electrode piece 412, the peripheral electrode piece 421, and the central electrode piece 422.

  As a result, the capsule 6 rotates so that the fluoroscopic part 622 is positioned on the upper electrode 41 side, the first particles A dielectrophoresis toward the upper electrode 41 side, and the second particles B move toward the lower electrode 42 side. And dielectrophoresis. As a result, the see-through portion 622 of the capsule 6 is located on the upper electrode 41 side, and the first particles A are located so as to correspond to the see-through portion 622. In this state, white is visually recognized as the display color.

<3> Black Display Next, the black display state will be described.
The selection means 43 selects electrode pieces 411, 412, and 422 as electrode pieces to which a voltage is applied. Next, an AC voltage applied between the peripheral electrode piece 411 and the central electrode piece 412 and the central electrode piece 422 is generated from the AC power supply 44. At the same time, a DC voltage is generated from the DC power source 83 such that the peripheral electrode piece 411 and the central electrode piece 412 are positive and the central electrode piece 422 is negative. The generated AC voltage and DC voltage are superimposed by the superimposing unit 100, and the superimposed voltage is applied between the central electrode piece 412, the peripheral electrode piece 421, and the central electrode piece 422.

  As a result, the capsule 6 rotates so that the fluoroscopic part 622 is positioned on the upper electrode 41 side, the second particles B dielectrophoresis toward the upper electrode 41 side, and the first particles A move toward the lower electrode 42 side. And dielectrophoresis. As a result, the see-through portion 622 of the capsule 6 is located on the upper electrode 41 side, and the second particles B are located so as to correspond to the see-through portion 622. In this state, black is visually recognized as the display color.

  As in the above-described embodiment, the colored portion 621 may be located on the upper electrode 41 side, and the second particles B may be located so as to correspond to the colored portion 621. According to this, darker (sunk) black can be displayed as compared with the case where the fluoroscopic part 622 is located on the upper electrode 41 side. In this case, a DC voltage may be generated from the DC power supply 83 so that the peripheral electrode piece 411 and the central electrode piece 412 are negative and the central electrode piece 422 is positive.

As described above, by simultaneously applying the AC voltage and the DC voltage, the capsule 6 can be rotated and the first particles A and the second particles B can be moved (dielectrophoresis) at the same time. The time until is displayed is shortened. Thereby, the display color can be switched quickly. In the present specification, “simultaneous” means that an AC voltage generated from the AC power supply 44 and a DC voltage generated from the DC power supply 83 are both applied between the upper electrode 41 and the lower electrode 42. It means that time (state) exists, and the application of the AC voltage and the application of the DC voltage are not limited to those starting at the same timing and ending at the same timing.
According to the second embodiment as described above, the same effect as that of the first embodiment can be exhibited.

<< Third Embodiment >>
Next, a third embodiment of the electrophoretic display device of the present invention will be described.
FIG. 10 is a schematic longitudinal sectional view showing a third embodiment of the electrophoretic display device of the invention.
Hereinafter, the electrophoretic display device according to the third embodiment will be described with a focus on differences from the above-described embodiments, and description of similar matters will be omitted.

The electrophoretic display device according to the third embodiment of the present invention is the same as the electrophoretic display device of the first embodiment, except that the configuration of the rotating means for rotating the capsule is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above.
As shown in FIG. 10, the rotating means 8 </ b> A of the present embodiment has a pair of electrode pieces 81 </ b> A and 82 </ b> A that are arranged to oppose each other in the left-right direction via the cell 31. That is, in the electrophoretic display device 1 of the present embodiment, the upper electrode 41 and the lower electrode 42 that are opposed to each other in the vertical direction with respect to the cell 31, and the pair of electrode pieces 81A and 82A that are opposed to each other in the horizontal direction. Is provided. A predetermined voltage is applied from the DC power supply 83 between the pair of electrode pieces 81A and 82A. According to such a rotating means 8A, the capsule 6 can be rotated and the posture of the capsule 6 can be determined with a relatively simple configuration.

In the present embodiment, the capsule 6 can be rotated if a DC voltage is ignited between the electrode pieces 81 </ b> A and 82 </ b> A by the DC power supply 83, and an AC voltage is applied between the upper electrode 41 and the lower electrode 42 by the AC power supply 44. When applied, the first particles A and the second particles B can be dielectrophoresed.
According to the third embodiment as described above, the same effect as that of the first embodiment can be exhibited.

<< Fourth Embodiment >>
Next, a fourth embodiment of the electrophoretic display device of the invention will be described.
FIG. 11 is a schematic longitudinal sectional view showing a fourth embodiment of the electrophoretic display device of the invention.
Hereinafter, the electrophoretic display device according to the fourth embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.

The electrophoretic display device according to the fourth embodiment of the present invention is the same as the electrophoretic display device of the first embodiment, except that the pixel configuration is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above.
As shown in FIG. 11, the pixel P has three cells 31a, 31b, and 31c arranged in parallel.

The cells 31a, 31b, and 31c contain capsules 6a, 6b, and 6c, respectively. The color of the colored portion 621 of the capsule 6a is cyan, the color of the colored portion 621 of the capsule 6b is magenta, and the color of the colored portion 621 of the capsule 6c is red.
That is, the pixel P is composed of a cell 31a capable of displaying cyan as a display color, a cell 31b capable of displaying magenta, and a cell 31c capable of displaying red. According to such a pixel P, full color display is possible by arbitrarily combining the display colors of the three cells 31a, 31b, and 31c.

  For example, when displaying black, all the three cells 31a, 31b, 31c may be displayed in black. When displaying magenta, the cell 31b is set in magenta display, and the cells 31a, 31c are displayed. What is necessary is just to make it a white display state, and when it is desired to display an intermediate color between cyan and magenta, the cell 31a should be in the cyan display state, the cell 31b should be in the magenta display state, and the cell 31c should be in the white display state. The arrangement and shape of the cells 31a, 31b, 31c are not particularly limited.

  In this embodiment, the color of the colored portion 621 of the capsule 6a is cyan, the color of the colored portion 621 of the capsule 6b is magenta, and the color of the colored portion 621 of the capsule 6c is red. For example, the color of the colored portion 621 of the capsule 6a is red (R), the color of the colored portion 621 of the capsule 6b is green (G), and the color of the colored portion 621 of the capsule 6c is blue (B). It is good. This also enables full color display as in the present embodiment.

According to the third embodiment as described above, the same effect as that of the first embodiment can be exhibited.
The electrophoretic display device 1 as described above can be incorporated into various electronic devices. As an electronic apparatus of the present invention provided with an electrophoretic display device, for example, an electronic paper, an electronic book, a television, a viewfinder type, a monitor direct view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, an electronic newspaper, Examples include a word processor, a personal computer, a workstation, a videophone, a POS terminal, and a device equipped with a touch panel.

Of these electronic devices, an electronic paper will be described as an example for specific description.
FIG. 12 is a perspective view showing an embodiment when the electronic apparatus of the present invention is applied to electronic paper.
An electronic paper 600 shown in FIG. 12 includes a main body 601 composed of a rewritable sheet having the same texture and flexibility as paper, and a display unit 602.
In such an electronic paper 600, the display unit 602 includes the electrophoretic display device 1 as described above.

Next, an embodiment when the electronic apparatus of the present invention is applied to a display will be described.
FIG. 13 is a diagram showing an embodiment when the electronic apparatus of the present invention is applied to a display. Among these, (a) in FIG. 13 is a sectional view and (b) is a plan view.
A display (display device) 800 illustrated in FIG. 13 includes a main body 801 and an electronic paper 600 that is detachably attached to the main body 801. The electronic paper 600 has the same configuration as described above, that is, the configuration shown in FIG.

  The main body 801 has an insertion port 805 into which the electronic paper 600 can be inserted on the side (right side in FIG. 13), and two pairs of conveying rollers 802a and 802b are provided inside. When the electronic paper 600 is inserted into the main body 801 through the insertion port 805, the electronic paper 600 is installed in the main body 801 in a state of being sandwiched between the pair of conveyance rollers 802a and 802b.

  A rectangular hole 803 is formed on the display surface side of the main body 801 (the front side in FIG. 13B), and a transparent glass plate 804 is fitted in the hole 803. . Thereby, the electronic paper 600 installed in the main body 801 can be viewed from the outside of the main body 801. That is, in the display 800, the display surface is configured by visually recognizing the electronic paper 600 installed in the main body 801 on the transparent glass plate 804.

In addition, a terminal portion 806 is provided at a leading end portion (left side in FIG. 13) of the electronic paper 600 in the insertion direction, and the terminal is provided inside the main body portion 801 with the electronic paper 600 installed on the main body portion 801. A socket 807 to which the unit 806 is connected is provided. A controller 808 and an operation unit 809 are electrically connected to the socket 807.
In such a display 800, the electronic paper 600 is detachably installed on the main body 801, and can be carried and used while being detached from the main body 801.

  The electrophoretic display sheet, electrophoretic display device, and electronic apparatus of the present invention have been described above based on the illustrated embodiments, but the present invention is not limited to these. For example, in the electrophoretic display sheet, the electrophoretic display device, and the electronic apparatus of the present invention, the configuration of each part can be replaced with an arbitrary configuration that exhibits the same function, and an arbitrary configuration is added. You can also

Moreover, although embodiment mentioned above demonstrated the spherical cell, it is not limited to this, For example, the cell may comprise the cube shape. In this case, the base body may be composed of a pair of upper and lower substrates and a spacer member composed of silicone rubber or the like interposed therebetween.
In the embodiment described above, the first electrode and the second electrode have been described as being composed of a central electrode piece and a peripheral electrode piece, respectively, but the shape and number of the electrode pieces are not limited thereto, For example, you may be comprised with three or more electrode pieces.

In the above-described embodiment, the electrophoretic display device has been described as having a plurality of pixels. However, the number of pixels is not particularly limited, and may be one, for example.
Moreover, in 2nd Embodiment mentioned above, although what has a pair of electrode piece as a rotation means was demonstrated, it is not limited to this, For example, it may replace with a pair of electrode piece and may have a pair of electromagnetic coils. Good.

1 is a schematic longitudinal sectional view showing a first embodiment of an electrophoretic display device of the present invention. It is a figure which shows the rotation means and moving means with which the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal cross-sectional view which shows the action | operation of the electrophoretic display apparatus shown in FIG. It is a typical longitudinal section showing a 2nd embodiment of an electrophoretic display device of the present invention. It is a typical longitudinal section showing a 3rd embodiment of an electrophoretic display device of the present invention. It is a typical longitudinal section showing a 4th embodiment of an electrophoretic display device of the present invention. It is a perspective view which shows embodiment at the time of applying the electronic device of this invention to electronic paper. It is a figure which shows embodiment at the time of applying the electronic device of this invention to a display.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electrophoretic display device 2 ... Electrophoretic display sheet 3 ... Base | substrate 31 ... Cell (accommodating part) 31a, 31b, 31c ... Cell 4 ... Moving means 41 ... Upper electrode (1st electrode) 42 ... Lower electrode (second electrode) 411, 421 ... Peripheral electrode piece 412, 422 ... Center electrode piece 43 ... Selection means 44 ... AC power supply (AC power supply means) 5 ... Dielectric liquid 6, 6a, 6b, 6c: Capsule 61: Internal space 62 ... Shell 621 ... Colored part 622 ... Perspective part 623 ... Intermediate color part 7 ... Dispersion medium 8, 8A ... Rotating means 81A, 82A ... Electrode piece 83 …… DC power supply 9 …… Circuit board 91 …… Base part 100 …… Overlapping part 600 ... Electronic paper 601 ... Main body 602 ... Display unit 800 ... Display 801 ... Main body part 80 a, 802b ... Transport roller pair 803 ... Hole 804 ... Transparent glass plate 805 ... Insertion port 806 ... Terminal part 807 ... Socket 808 ... Controller 809 ... Operation part A ... First particle B ... second particles H1, H2 ... alternating magnetic field H11, H21 ... strong electric field part H12, H22 ... weak electric field part P ... pixel

Claims (19)

A capsule in which an internal space is filled with a dispersion medium in which first particles and second particles having different colors are dispersed;
An accommodating portion for rotatably accommodating the capsule;
A first electrode and a second electrode which are arranged opposite to each other via the housing portion and have a plurality of electrode pieces, and AC power supply means for applying an AC voltage therebetween, the first particle and the first electrode Moving means for moving the two particles in the dispersion medium;
Rotating means for rotating the capsule,
When the dielectric constants of the first particles, the second particles, and the dispersion medium are ε1, ε2, and ε3, respectively, the relationship of ε1>ε3> ε2 is satisfied,
The capsule has an electrophoretic display sheet characterized by having a see-through portion that can be visually recognized through the wall portion.   The moving means selects the electrode piece to which the AC voltage is applied from the plurality of electrode pieces of the first electrode and the second electrode, thereby obtaining the AC voltage of the first electrode and the second electrode. The applied region is changed, thereby giving a difference between the electric field strength near the first electrode and the electric field strength near the second electrode, and the difference in dielectric constant between the first particles and the second particles The electrophoretic display sheet according to claim 1, wherein the electrophoretic display sheet is configured to move the first particles and the second particles by using the first and second particles.   The position of the capsule is determined by rotating the capsule by the rotating means, and the first particles are relatively small in the vicinity of the strong electric field portion where the strength of the AC electric field is relatively large by the moving means. 3. The electrophoretic display sheet according to claim 1, wherein the electrophoretic display sheet is configured to change a color in the housing portion visually recognized through the first electrode by moving the second particles in the vicinity of a weak electric field portion. 4. .   The moving means has a selection means for selecting an electrode piece to which the AC voltage is applied from the plurality of electrode pieces, and a region to which the voltages of the first electrode and the second electrode are applied by the operation of the selection means. The electrophoretic display sheet according to claim 1, wherein the electrophoretic display sheet is changed.   The first electrode and the second electrode each have a central electrode piece and a peripheral electrode piece provided so as to surround the periphery of the central electrode piece as the plurality of electrode pieces. 4. The electrophoretic display sheet according to any one of 3.   The moving means is configured to apply an alternating voltage between the central electrode piece of the first electrode and the central electrode piece and the peripheral electrode piece of the second electrode piece, and the central electrode piece of the first electrode. The electrophoretic display sheet according to claim 5, wherein an alternating voltage can be applied between the peripheral electrode piece and the central electrode piece of the second electrode piece.   The electrophoretic display sheet according to claim 1, wherein the container is filled with a liquid together with the capsule, and the capsule is floating.   The electrophoretic display sheet according to claim 1, wherein the capsule has a substantially spherical shape.   The electrophoretic display sheet according to claim 1, wherein the fluoroscopic part is substantially colorless and transparent.   The electrophoretic display sheet according to claim 1, wherein the capsule has a colored portion at a portion different from the see-through portion.   The electrophoretic display sheet according to claim 10, wherein the capsule has an intermediate color portion that forms an intermediate color between the fluoroscopic portion and the coloring portion. The capsule has a positively charged region that is positively charged and a negatively charged region that is negatively charged;
The electrophoretic display sheet according to claim 10, wherein the rotating unit is configured to rotate the capsule by applying an electric field or a magnetic field to the capsule.   The electrophoretic display sheet according to claim 12, wherein one of the positively charged region and the negatively charged region is located in the see-through portion and the other is located in the colored portion.   The rotating means includes a pair of capsule rotating electrodes arranged opposite to each other via the housing portion, and a DC power source means for applying a DC voltage between the pair of capsule rotating electrodes. The electrophoretic display sheet according to claim 12 or 13, wherein the capsule is rotated by applying a DC voltage between the pair of capsule rotating electrodes.   The electrophoretic display sheet according to claim 14, wherein the first electrode and the second electrode also serve as the pair of capsule rotation electrodes.   The AC voltage for moving the first particles and the second particles and the DC voltage for rotating the capsule are superimposed and applied between the first electrode and the second electrode. The electrophoretic display sheet according to claim 15, which is configured.   By setting a voltage application pattern to the first electrode and the second electrode, the colored portion of the capsule is positioned on the first electrode side, and the see-through portion of the capsule is the first state. A second state in which the first particles are unevenly distributed in the capsule on the first electrode side, and the see-through part of the capsule is located on the first electrode side. The electrophoretic display sheet according to claim 15 or 16, wherein one of two particles can be selected from a third state located on the first electrode side in the capsule.   An electrophoretic display device comprising: the electrophoretic display sheet according to claim 1; and a substrate provided on the second electrode side of the housing portion.   An electronic apparatus comprising the electrophoretic display device according to claim 18.

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