JP5092518B2 - Display device and display medium using the same - Google Patents

Description

  The present invention relates to a display device using electrowetting and a display medium using the display device, and more particularly to a display device and a display medium capable of maintaining a display state even after an applied voltage is stopped.

In recent years, a microcapsule containing electrophoretic particles and a dispersion medium is sandwiched between two electrodes as an electrophoretic display element, and a voltage is applied to the electrophoretic display element so that the electrophoretic particles have different polarities in the microcapsule. Display devices using the phenomenon of electrophoresis toward an electrode having a liquid crystal have been developed (Patent Documents 1 and 2). In this display device, color display is possible by using microcapsules of each color of yellow, magenta, and cyan as the dispersion medium and sandwiching each color between the electrodes.
In addition, water and colored oil are sealed in a plurality of cells each having a hydrophobic electrode and a hydrophilic electrode facing each other. When no voltage is applied, the colored oil is on the hydrophobic electrode surface. A display device has been developed that utilizes the fact that colored oil moves and accumulates at a predetermined location of a hydrophobic electrode when a voltage is applied between the electrodes. Also in this display device, color display is possible by using colored oils such as yellow, magenta, and cyan. Furthermore, an electrode is partially formed over the entire area of the optical switch, and when a voltage is applied between the electrodes, oil is always moved to a portion without the electrode as a direction defining means. There has been developed a display device which is provided and maintains a memory property by continuously applying a voltage to this electrode (Patent Documents 3, 4, and 5).
JP 2002-357853 A Japanese Patent Laid-Open No. 2002-333643 International Publication WO 2004/104670 International Publication WO 2004/068208 International Publication WO 2004/104671

However, the conventional display devices disclosed in Patent Documents 1 and 2 have a problem in that it is difficult to arrange the microcapsules without causing defects, resulting in a reduction in image quality.
Further, in the conventional display devices disclosed in Patent Documents 3, 4, and 5, the oil that has moved and accumulated at a predetermined position of the hydrophobic electrode due to voltage application spreads on the surface of the hydrophobic electrode when voltage application is stopped. Therefore, there was a problem that there was no so-called memory property. For this reason, energization is always required, which has been a problem in reducing power consumption. Furthermore, when the direction defining means disclosed in Patent Document 5 is used, there is a problem that the oil moves and accumulates in a portion where there is no electrode, and the drive may become unstable.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a display device with a quick response and low power consumption, and a display medium using the display device.

  In order to achieve such an object, the present invention can provide hydrophobicity when an electrode whose surface is coated with a hydrophobic insulating layer is arranged in a cell and a voltage is applied in a state where water and oil are filled in the cell. This is based on electrowetting (hereinafter referred to as EW) in which oil that has spread throughout the insulating layer moves to one place. Specifically, when the electrode has a smaller area than the hydrophobic insulating layer and voltage is applied, the oil moves from the portion where the electrode is present under the hydrophobic insulating layer to the portion where the electrode is not present. This is used as a direction defining means. Also, the thickness of a part of the hydrophobic insulating layer that covers the electrode is increased, and when a voltage is applied, the oil moves to the thick part of the insulating layer and is used as a direction defining means. It is.

That is, the present invention includes a container having at least a first electrode and a second electrode and enclosing therein a first liquid and a second liquid that are not mixed with each other, and the first electrode and the second electrode One is electrically insulated from the first liquid and the second liquid, the first liquid has conductivity or polarity, and voltage is applied to one or both of the first electrode and the second electrode. In the display device including at least one display cell capable of displaying by changing the positions of the first liquid and the second liquid by applying the liquid, at least one of the containers is a transparent substrate 1 A pair of base materials, a wall portion that holds the one set of base materials facing each other so as to form a liquid sealed space, and the liquid sealed space side of one base material are electrically independent from each other. The first A electrode and the first B electrode, the first A electrode and the first electrode A first insulating layer and a first insulating layer covering each of the electrodes; a narrow insulating layer connecting the first insulating layer and the first insulating layer; and the other substrate side of the liquid filled space. An electrode not formed in which the first A electrode and the first B electrode do not exist in the vicinity of the first A insulating layer and the first B insulating layer connected by the narrow insulating layer. A region is provided, and the first A electrode and the first B electrode are electrically insulated from the first liquid and the second liquid, and an applied voltage between the first A electrode and the second electrode, or A second liquid is movable between the first A insulating layer and the first B insulating layer via the narrow insulating layer by an applied voltage between the first B electrode and the second electrode; The narrow insulating layer is located at a position where the first liquid and the second liquid move. A liquid holding means for maintaining the position of the moved first liquid and second liquid even after the applied voltage is stopped to develop a memory property, wherein the narrow insulating layer The second liquid located on the first A insulating layer or the first B insulating layer has a width and a length that cannot move when it is stopped, and the portion of the wall portion exposed to the container is exposed. Water droplet contact angle θ1 representing hydrophilicity, water droplet contact angle θ2 representing hydrophilicity of the surfaces of the first A insulating layer and the first B insulating layer, and water droplet contact angle representing hydrophilicity of the surface of the narrow insulating layer The relationship of θ1 <θ2 ≦ θ3 is established with θ3, and the area ratio between the first A electrode and the electrode non-formation region and the area ratio between the first B electrode and the electrode non-formation region are 100: 1. ˜1: 1, and the width of the narrow insulating layer is 0.01˜10000 μm, long Ranged der so that construction of the 0.01~1000μm.

In addition, the present invention includes a container having at least a first electrode and a second electrode and enclosing therein a first liquid and a second liquid that are not mixed with each other, and the first electrode and the second electrode One is electrically insulated from the first liquid and the second liquid, the first liquid has conductivity or polarity, and voltage is applied to one or both of the first electrode and the second electrode. In the display device including at least one display cell capable of displaying by changing the positions of the first liquid and the second liquid by applying the liquid, at least one of the containers is a transparent substrate 1 A pair of base materials, a wall portion that holds the one set of base materials facing each other so as to form a liquid sealed space, and the liquid sealed space side of one base material are electrically independent from each other. The first A electrode and the first B electrode, the first A electrode and the first B electrode A first insulating layer, a first insulating layer, a first insulating layer, an intermediate insulating layer connecting the first insulating layer and the first insulating layer, and a second substrate disposed on the other substrate side of the liquid enclosure space. The intermediate insulating layer is located at a boundary portion between the first A electrode and the first B electrode so as to cover a part of the first A electrode and the first B electrode, and the surface of the intermediate insulating layer is The first A insulating layer and the first B insulating layer protrude from the surfaces of the first insulating layer and the liquid sealing space, and the first A electrode and the first B electrode are electrically insulated from the first liquid and the second liquid, Due to an applied voltage between the first A electrode and the second electrode, or an applied voltage between the first B electrode and the second electrode, the second liquid passes over the intermediate insulating layer and on the first A insulating layer. The intermediate insulating layer is movable between the first B insulating layer and the intermediate insulating layer. Even after the applied voltage is stopped at the position where the first liquid and the second liquid are moved, the positions of the moved first liquid and the second liquid are maintained and the memory property is expressed. In the liquid holding means, the height at which the surface of the intermediate insulating layer protrudes toward the liquid sealing space from the surfaces of the first A insulating layer and the first B insulating layer is when the applied voltage is stopped. A contact angle θ1 of a water droplet representing a hydrophilic property of a portion of the wall portion exposed in the container, the height being such that the second liquid positioned on the first A insulating layer or the first B insulating layer does not get over. Between the contact angle θ2 of the water droplet representing the hydrophilicity of the surfaces of the first A insulating layer and the first B insulating layer and the contact angle θ3 of the water droplet representing the hydrophilicity of the surface of the intermediate insulating layer, θ1 <θ2 ≦ θ3 And the first A electrode without the intermediate insulating layer and the first A The area ratio between the intermediate insulating layer covering the electrode and the area ratio between the first B electrode without the intermediate insulating layer and the intermediate insulating layer covering the first B electrode is 100: 1 to 1: 1. in the range, the surface of the intermediate insulating layer is between the first 1A insulating layer and the second 1B height the protruding liquid confining space side than the surface of the insulating layer is a so that der range 1~100μm configuration.

As another aspect of the present invention, the intermediate insulating layer includes a lower insulating layer positioned at a boundary portion between the first A electrode and the first B electrode, and an upper insulating layer positioned thereon, the upper insulating layer Are made of the same material as the first A insulating layer and the first B insulating layer .
In this aspect, the formation of the intermediate insulating layer is easy, and the contact angle of water droplets representing the hydrophilicity of the lower insulating layer is not limited, and the range of selection of the material constituting the intermediate insulating layer is expanded.
As another aspect of the present invention, the lower insulating layer is configured to be thicker than the first A electrode and the first B electrode.
In this aspect, it is easier to form the intermediate insulating layer.
As another aspect of the present invention, a light shielding film having a desired pattern shape is provided outside the transparent substrate on the display recognition side.
In this aspect, ON / OFF display based on whether or not the second liquid is positioned on the electrode surface in a portion where the light shielding film does not exist is possible.

As another aspect of the present invention, the second liquid is a colored oil.
In this aspect, information or the like can be displayed in a desired color.
As another aspect of the present invention, a reflective display that recognizes light reflected by the display cell, and the colored oil that is the second liquid sealed in each display cell is yellow, magenta, or cyan. It was set as either one.
In this aspect, a reflection type full-color display is possible.
As another aspect of the present invention, the display is a transmission method for recognizing light transmitted through the display cell, the first liquid is colored water, and the colored oil as the second liquid is light-shielding black. It was set as the structure which is oil.
In this aspect, it is possible to display the color that is transmitted through the colored water and black.

As another aspect of the present invention, the colored water that is the first liquid sealed for each display cell is configured to be red, green, or blue.
In this aspect, transmissive full-color display is possible.
As another aspect of the present invention, the first A electrode and the first B electrode have the same shape and position for each display cell.
In this aspect, uniform display characteristics can be obtained in the entire display device.

  The display medium of the present invention has one or more of the display devices described above, and has an input terminal for supplying power and a signal from an external device to each display cell of the display device. The external device can be connected to and disconnected from the external device.

According to the present invention, the position change of the second liquid using EW is quickly and reliably performed by the applied voltage to the first A electrode and the second electrode or the applied voltage to the first B electrode and the second electrode. In addition, a fast response display is possible, and the moved first liquid and the second liquid are held even after the applied voltage is stopped by the narrow insulating layer or the intermediate insulating layer as the liquid holding means. Since the memory property is exhibited, it is not necessary to energize constantly, and a display device with low power consumption and quick response is possible.
In addition, since the display medium of the present invention can maintain the memory property even when the display medium is detached from the external device, it is not necessary to always energize and the information can be carried only by the display medium.

Embodiments of the present invention will be described below with reference to the drawings.
[Display device]
FIG. 1 is a plan view showing an example of the display device of the present invention. As shown in FIG. 1, the display device 1 of the present invention includes a plurality of display cells 11 (seven display cells 11A, 11B, 11C, 11D, 11E, and 11F in the illustrated example). Each display cell 11 includes at least a first electrode and a second electrode, and includes a container enclosing therein a first liquid and a second liquid that are not mixed with each other. One of the two electrodes is electrically insulated from the first liquid and the second liquid, the first liquid has conductivity or polarity, and a voltage is applied to one or both of the first electrode and the second electrode. Is applied to change the positions of the first liquid and the second liquid and display is performed. Each display cell 11 has a pixel portion 12 and a space portion 13, and the pixel portion 12 can perform ON / OFF display by changing the positions of the first liquid and the second liquid by applying a voltage. Thus, the display device 1 can display numeric information of “0” to “9”. The display device 1 of the present invention has a memory property that can maintain ON / OFF display in the pixel portion 12 of each display cell 11 even after the applied voltage is stopped.
In FIG. 1, the boundary line of each display cell 11 is indicated by a chain line, and the space portion 13 is hatched.

<First Embodiment>
FIG. 2 is an enlarged longitudinal sectional view showing the first embodiment of the display device of the present invention, and shows the structure of one display cell by the longitudinal section taken along the line II of FIG. As shown in FIG. 2, in the display cell 11 </ b> A, a first liquid 31 having conductivity or polarity and a second liquid 32 that is hydrophobic are sealed in a container 21. Although FIG. 2 shows the structure of the display cell 11A, the other display cells have the same structure.
The container 21 includes a pair of base materials 22 and 23 and a wall portion 29 that supports the pair of base materials 22 and 23 to face each other so as to form a liquid sealed space S. One substrate 22 has a first A electrode 24 and a first B electrode 25 disposed on the liquid sealing space S side electrically independently of each other, and a first A insulating layer 27A and a first B insulating layer covering these, respectively. A layer 27B is provided.

FIG. 3 is a plan view showing the first A electrode 24 and the first B electrode 25 in the display cell 11A, and FIG. 4 is a plan view showing the first A insulating layer 27A and the first B insulating layer 27B. As shown in FIG. 4, the first A insulating layer 27 </ b> A and the first B insulating layer 27 </ b> B that are spaced apart via the gap 27 ′ are connected by a narrow insulating layer 28. In addition, as shown in FIG. 3, the first A electrode 24 and the first B electrode 25 exist in the vicinity of the first A insulating layer 27A and the first B insulating layer 27B connected by the narrow insulating layer 28, respectively. Non-electrode forming regions 24 'and 25' are set. The presence of such electrode non-formation regions 24 ′ and 25 ′ constitutes a direction regulating means for the second liquid 32 using EW. Further, the other base material 23 includes a second electrode 26 on the liquid sealing space S side.
In this container 21, the base material 23 side is a display recognition side, and at least the base material 23 is a transparent base material. In addition, a light shielding film 30 is disposed outside the base material 23, a portion where the light shielding film 30 does not exist is the pixel portion 12, and a portion where the light shielding film 30 is disposed is the space portion 13. .

In the display cell 11A, the first A electrode 24 and the first B electrode 25 are electrically insulated from the first liquid 31 and the second liquid 32 by the first A insulating layer 27A and the first B insulating layer 27B. Yes. And the contact angle θ1 of the water droplet representing the hydrophilicity of the portion exposed in the container 21 of the wall 29, the contact angle θ2 of the water droplet representing the hydrophilicity of the surfaces of the first A insulating layer 27A and the first B insulating layer 27B, A relationship of θ1 <θ2 ≦ θ3 is established between the contact angle θ3 of the water droplet representing the hydrophilicity of the surface of the narrow insulating layer 28. By establishing such a contact angle relationship of water droplets representing hydrophilicity, the second liquid 32 does not spread on the wall portion 29 and reliably covers the first A insulating layer 27A or the first B insulating layer 27B. be able to. When the relationship of θ2 <θ3 is established, the direction defining means using EW described later functions more effectively.
In the present invention, the contact angle of water droplets representing hydrophilicity refers to dropping one drop (fixed amount) of pure water (distilled water for liquid chromatography (manufactured by Pure Chemical Co., Ltd.)) on the surface of the measurement object, It means the contact angle measured according to the θ / 2 method after a predetermined time has elapsed. The same applies to the following present invention.

  As shown in FIG. 2, the display cell 11A has the first A electrode 24 and the second electrode 26 in a state where the second liquid 32 is located on the first A insulating layer 27A (liquid sealed space S1). When a voltage is applied between them, the direction defining means using EW that moves the second liquid 32 from the first A electrode 24 in the direction of the electrode non-formation region 24 'functions as shown by a solid arrow in FIG. As a result, the second liquid 32 on the first A insulating layer 27A moves onto the first B insulating layer 27B (liquid sealed space S2) via the narrow insulating layer 28 (FIG. 5A). When the applied voltage is stopped in this state, the narrow insulating layer 28 acts as a liquid holding means, and the second liquid 32 moved on the first B insulating layer 27B (the liquid sealing space S2) is held as it is, so that the memory property is improved. It is expressed (FIG. 5 (B)).

  Further, when a voltage is applied between the first B electrode 25 and the second electrode 26, as shown by a chain line arrow in FIG. 3, the EW that moves the second liquid 32 from the first B electrode 25 toward the electrode non-formation region 25 ′. The direction defining means using the functions. As a result, the second liquid 32 moves onto the first A insulating layer 27A (liquid sealed space S1) via the narrow insulating layer 28 (FIG. 5C). When the applied voltage is stopped in this state, the narrow insulating layer 28 acts as a liquid holding means, and the second liquid 32 moved on the first A insulating layer 27A (the liquid sealing space S1) is held as it is, so that the memory property is improved. It is expressed (FIG. 5 (D)). In such a display cell 11A, ON / OFF depending on whether or not the second liquid 32 is located on the insulating layer (the first A insulating layer 27A in the illustrated example) of the portion (pixel portion 12) where the light shielding film 30 does not exist. Display is possible.

  Since the base material 23 constituting the display cell 11A is located on the display recognition side as described above, it is a transparent base material. Further, the substrate 22 on the opposite side does not have to be a transparent substrate when the display cell 11A performs a reflective display, but a transparent substrate when the display cell 11A performs a transmissive display. Use wood. The base materials 22 and 23 can use transparent base materials, such as a glass base material and a transparent resin base material, for example. In addition, when the base material 22 does not have to be a transparent base material, a non-transparent glass having a roughened surface or a metal film deposited on a surface opposite to the electrode forming surface, such as a metal substrate or a ceramic substrate. An opaque resin base material kneaded with a base material, a dye or a pigment can be used. The thickness of the base materials 22 and 23 can be set in consideration of the material to be used, and can be set as appropriate within a range of, for example, 10 μm to 5 mm, preferably 100 μm to 2 mm.

  The first A electrode 24, the first B electrode 25, and the second electrode 26 constituting the display cell 11A are respectively connected to a voltage application device (not shown), and for example, the charge of the electrode can be arbitrarily set in the range of applied voltage 1 to 300V. It can be controlled. The second electrode 26 is located on the display recognition side. For example, using indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), etc., sputtering, vacuum evaporation, CVD, etc. It can be set as the transparent electrode formed with the general film-forming method. The second electrode 26 only needs to be capable of making the first liquid 31 substantially equipotential with the second electrode 26. In addition to the above-described surface electrode, for example, one or more second electrodes 26 are provided in the liquid enclosure space S. It may be a needle electrode, a mesh electrode, or the like. Further, the first A electrode 24 and the first B electrode 25 are transparent electrodes as in the case of the second electrode 26 when the display cell 11A performs transmissive display. On the other hand, when the display cell 11A performs a reflective display, the first A electrode 24 and the first B electrode 25 may be metal electrodes such as Cu, Ag, Au, and Al instead of the transparent electrodes.

  The area ratio between the first A electrode 24 and the electrode non-formation region 24 ′ and the area ratio between the first B electrode 25 and the electrode non-formation region 25 ′ are 100: 1 to 1 in order to make the direction definition by EW function effectively. : 1, preferably 20: 1 to 3: 1, more preferably 20: 1 to 4: 1. When the area of the electrode non-formation regions 24 'and 25' exceeds the above range, the first region between the first A insulating layer 27A (liquid sealed space S1) and the first B insulating layer 27B (liquid sealed space S2) is used. When the voltage required for the movement of the second liquid 32 becomes high and the area of the electrode non-formation regions 24 ′ and 25 ′ is less than the above range, the direction definition by EW becomes difficult to function effectively.

The first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 constituting the display cell 11A satisfy the above-described water droplet contact angle magnitude relationship (θ1 <θ2 ≦ θ3). The insulating material constituting the first A insulating layer 27A and the first B insulating layer 27B and the insulating material constituting the narrow insulating layer 28 may be the same or different. For example, insulating materials such as polyimide resin, SiO ₂ , SiN ₄ , acrylic resin, perylene, fluorine resin, polyamide resin, polyethylene terephthalate, polypropylene, polystyrene, silicone resin, quartz, epoxy resin, polyethylene, polytetrafluoroethylene, etc. It may be made up of, and may be one in which a small amount of current flows. Among these, by using an insulating material such as perylene, fluorine-based resin, or silicone resin, water droplets representing the hydrophilicity of the surfaces of the first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 are used. , The wettability with respect to the second liquid 32 is improved, and the thickness uniformity of the second liquid 32 is improved. The thickness of the first A insulating layer 27A and the first B insulating layer 27B depends on the insulating material used so that the first A electrode 24 and the first B electrode 25 can be electrically insulated from the first liquid 31 and the second liquid 32. It can set suitably according to this, For example, it can set in the range of 0.01-10 micrometers.
When the display cell 11A performs a transmissive display, the first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 select an insulating material having transparency from the above insulating materials. Form.

  Further, the width W and the length L (see FIG. 4) of the narrow insulating layer 28 are the second values located on the first A insulating layer 27A or the first B insulating layer 27B when the applied voltage is stopped. In order to prevent the liquid 32 from moving, the liquid 32 may be appropriately set in consideration of the wettability of the second liquid 32 with respect to the insulating material constituting the first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28. it can. For example, the width W of the narrow insulating layer 28 can be set in the range of 0.01 to 10,000 μm, preferably 1 to 5000 μm, and the length L can be set in the range of 0.01 to 1000 μm, preferably 0.1 to 500 μm. . When the width W is less than 0.01 μm and the length L is less than 0.01 μm, the area of the narrow insulating layer 28 as a passage is small, and the time required for the second liquid 32 to move increases and the response speed. Is not preferable. Further, when the width W exceeds 10,000 μm or the length L exceeds 1000 μm, the second liquid 32 tends to accumulate in the narrow insulating layer 28 as a passage when the second liquid 32 moves, and the first A insulating layer The movement of the second liquid 32 between 27A (the liquid sealed space S1) and the first B insulating layer 27B (the liquid sealed space S2) becomes insufficient, which may hinder the display.

  In the wall portion 29 constituting the display cell 11A, the contact angle of the water droplet representing the hydrophilicity of at least the portion exposed in the container 21 is such that the contact angle of the water droplet representing the hydrophilicity is large (θ1 <θ2 ≦ θ3). As long as the above is satisfied. Examples of the material constituting the wall portion 29 include an ultraviolet curable urethane acrylate resin, an epoxy resin, an epoxy acrylate resin, an ester acrylate resin, an acrylate resin, a thermosetting phenol resin, It may be made of a resin material such as a melamine resin, a fluorine resin, a polyester resin, an epoxy resin, a polyurethane resin, a polyimide resin, or a urea resin. Moreover, the height of the liquid enclosure space S formed by the wall portion 29 so that the base materials 22 and 23 are opposed to each other can be set in a range of 1 to 1000 μm, for example. In the present invention, for example, a wall portion that has a plurality of electrodes and is disposed on the outer peripheral portion of the entire display region to hold the base material has a magnitude relationship (θ1 < It does not have to satisfy θ2 ≦ θ3).

The first liquid 31 sealed in the container 21 is a liquid having conductivity or polarity, such as water, alcohol, or acid. On the other hand, the second liquid 32 is a hydrophobic liquid such as heptane, hexane, nonane, decane, octane, dodecane, tetradecane, octadecane, hexadecane, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, ethyl benzoate, etc. Of oil can be used. Further, it is preferable that a relationship of g1 ≦ g2 is established between the specific gravity g1 of the first liquid 31 and the specific gravity g2 of the second liquid 32.
In the present invention, the amount of the second liquid 32 can be appropriately set to be not less than the minimum amount for spreading over the entire area of the first A insulating layer 27A or the first B insulating layer 27B.
Further, in the present invention, the second liquid 32 can be colored oil, whereby information or the like can be displayed in a desired color.
When the display cell 11A is a transmissive display, the first liquid 31 can be a colored liquid and the second liquid 32 can be a light-shielding black oil. As a result, ON / OFF display can be performed by two colors of the color transmitted through the colored liquid 31 and the black color.

The light shielding film 30 constituting the display cell 11A may be a light shielding resin film, a metal film, a combination thereof, or the like, and is not particularly limited. Further, the light shielding film 30 may be colored in a desired color.
The first A electrode 24 and the first B electrode 25, and the first A insulating layer 27A and the first B insulating layer 27B described with reference to FIGS. 3 and 4 are examples of the display cell 11A. Is not limited to this. For example, the first A electrode 24, the first B electrode 25, and the electrode non-formation regions 24 ′, 25 ′ are rectangular as shown in FIG. 6, and the first A electrode 24 and the first B electrode 25 are covered. The 1A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 may be shaped as shown in FIG. Further, instead of the shape shown in FIG. 6, the first A electrode 24, the first B electrode 25, and the electrode non-formation regions 24 ′ and 25 ′ are shaped as shown in FIG. The first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 that cover the first B electrode 25 may be shaped as shown in FIG. Further, the first A electrode 24, the first B electrode 25, and the electrode non-formation regions 24 ′, 25 ′ are formed in a circular shape as shown in FIG. 9, and the first A electrode 24 and the first B electrode 25 are covered. The 1A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 may be shaped as shown in FIG.

  Further, the display cell 11A is not limited to the above-described structure. For example, as shown in FIG. 11, a structure in which the base material 22 side is set as a display recognition side and a light shielding film 30 is provided outside the base material 22 may be employed. In this case, the substrate 22 is a transparent substrate, and the first A electrode 24, the first B electrode 25, the first A insulating layer 27A, and the first B insulating layer 27B are also transparent. In addition, the base material 23 and the second electrode 26 are also transparent in the transmissive display. Alternatively, the light shielding film 30 may not be provided, and the display may be based on a change in position due to the movement of the first liquid 31 and the second liquid 32.

  Further, as shown in FIG. 12, a structure in which the wall portion 29 is directly fixed to the base material 22 without the first A insulating layer 27A and the first B insulating layer 27B may be employed. Also in this case, the first A electrode 24 and the first B electrode 25 are covered with the first A insulating layer 27A and the first B insulating layer 27B, respectively, and are electrically insulated from the first liquid 31 and the second liquid 32. Accordingly, in the liquid sealed space S, in addition to the first A insulating layer 27A and the first B insulating layer 27B present in the electrode non-formation regions 24 ′ and 25 ′, the first A existing around the remaining portion of the first A electrode 24. The insulating layer 27A and the first B insulating layer 27B existing around the remaining portion of the first B electrode 25 are exposed. However, the first A insulating layer 27A and the first B insulating layer 27B which are not present in the electrode non-formation regions 24 'and 25' as described above are arranged in the direction from the first A electrode 24 to the electrode non-formation region 24 'as described above. The direction defining function using the EW for moving the second liquid 32 and the direction defining function using the EW for moving the second liquid 32 from the first B electrode 25 toward the electrode non-formation region 25 ′ are obstructed. It must not be. Therefore, the first A insulating layer 27A existing around the remaining portion of the first A electrode 24 excluding the electrode non-forming region 24 'and the first insulating layer 27A existing around the remaining portion of the first B electrode 25 excluding the electrode non-forming region 25'. The number of 1B insulating layers 27B is preferably as small as possible within a range in which the first A electrode 24 and the first B electrode 25 can be electrically insulated from the first liquid 31 and the second liquid 32.

Further, the display cells constituting the display device of the present invention are not limited to the structure capable of displaying the numerical information “0” to “9” shown in FIG. For example, when the display cell is a reflective display, a plurality of display cells in which the colored oil as the second liquid is one of yellow, magenta, and cyan are arranged in a matrix or the like, and the reflective full color display It is good also as what performs. When the display cell is a transmissive display, the first liquid 31 is a colored liquid, the second liquid 32 is a light-shielding black oil, and the colored liquid 31 is any of red, green, and blue. A plurality of display cells may be arranged in a matrix or the like to perform transmissive full color display.
A plurality of unit cells having the same arrangement position and shape of the first A electrode 24 and the first B electrode 25 may be arranged in a matrix or the like. Thereby, for example, even if the light shielding film 30 is not present, uniform display characteristics can be obtained in the entire display device.

<Second Embodiment>
FIG. 13 is a view corresponding to FIG. 2 showing the second embodiment of the display device of the present invention, and shows the structure of one display cell. In the form shown in FIG. 13, a first liquid 31 having conductivity or polarity and a second liquid 32 that is hydrophobic are sealed in the container 41 of the display cell 11 </ b> A.
The container 41 includes a pair of base materials 42 and 43 and a wall portion 49 that supports the pair of base materials 42 and 43 so as to form a liquid sealed space S. One substrate 42 has a first A electrode 44 and a first B electrode 45 disposed on the liquid-filling space S side electrically independently of each other, and a first A insulating layer 47A and a first B insulating layer covering these, respectively. A layer 47B and an intermediate insulating layer 48 connecting the first A insulating layer 47A and the first B insulating layer 47B are provided.

  14 is a plan view showing the first A electrode 44 and the first B electrode 45 in the display cell 11A, and FIG. 15 is a plan view showing the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48. In FIG. 14, the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48 are indicated by a two-dot chain line. As shown in FIGS. 13 to 15, the first A insulating layer 47 </ b> A and the first B insulating layer 47 </ b> B are connected by an intermediate insulating layer 48, and the intermediate insulating layer 48 is connected to the first A electrode 44 and the first B electrode 45. It is located at the boundary part and covers a part of the first A electrode 44 and the first B electrode 45, and this covering part has a larger layer thickness than the first A insulating layer 47A and the first B insulating layer 47B.

  For the width W1 (see FIG. 14) where the intermediate insulating layer 48 covers a part of the first A electrode 44 and the width W2 (see FIG. 14) which covers a part of the first B electrode 45, direction definition by EW is more effective. Can be set to work. For example, the area ratio between the first A electrode 44 without the intermediate insulating layer 48 and the intermediate insulating layer 48 (the region of the width W1 covering the first A electrode 44), the first B electrode 45 without the intermediate insulating layer 48 and the intermediate insulating layer 48 The area ratio with the layer 48 (region of width W2 covering the first B electrode 45) is 100: 1 to 1: 1, preferably 20: 1 to 3: 1, more preferably 20: 1 to 4: 1. Can be set by range. When the area where the intermediate insulating layer 48 covers the electrode exceeds the above range, between the first A insulating layer 47A (liquid sealed space S1) and the first B insulating layer 47B (liquid sealed space S2). When the voltage required for the movement of the second liquid 32 becomes high and the area where the intermediate insulating layer 48 covers the electrode is less than the above range, the direction definition by the EW becomes difficult to function effectively, which is not preferable. Further, the interval W3 between the first A electrode 44 and the first B electrode 45 can be set, for example, in the range of 0.01 to 10000 μm, preferably 10 to 1000 μm.

Note that the shape of the intermediate insulating layer 48 covering the electrodes is not limited to that shown in FIG. 14, and is shown as, for example, the electrode non-formation regions 24 ′ and 25 ′ in FIGS. The shape can be changed.
Further, the surface of the intermediate insulating layer 48 protrudes closer to the liquid sealing space S than the surfaces of the first A insulating layer 47A and the first B insulating layer 47B. The height H (see FIG. 13) at which the surface of the intermediate insulating layer 48 protrudes more toward the liquid sealing space S than the surfaces of the first A insulating layer 47A and the first B insulating layer 47B is when the applied voltage is stopped. The second liquid 32 positioned on the first A insulating layer 47A or the first B insulating layer 47B is at a height that does not get over.
In this way, the presence of the intermediate insulating layer 48 thicker than the first A insulating layer 47A and the first B insulating layer 47B constitutes a direction regulating means for the second liquid 32 using EW, and the intermediate insulating layer 48 functions as a liquid holding means.
The other base material 43 includes a second electrode 46 on the liquid sealing space S side.

In this container 41, the base material 43 side is the display recognition side, and at least the base material 43 is a transparent base material. Further, a light shielding film 50 is disposed outside the base material 43, a portion where the light shielding film 50 does not exist is the pixel portion 12, and a portion where the light shielding film 50 is disposed is the space portion 13. .
In the display cell 11A, the first A electrode 44 and the first B electrode 45 are electrically connected from the first liquid 31 and the second liquid 32 by the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48. Is insulated. And in this invention, the contact angle (theta) 1 of the water droplet showing the hydrophilic property of the site | part exposed in the container 41 of the wall part 49, and the contact of the water droplet showing the hydrophilic property of the surface of 1A insulation layer 47A and 1B insulation layer 47B. A relationship of θ1 <θ2 ≦ θ3 is established between the angle θ2 and the contact angle θ3 of the water droplet representing the hydrophilicity of the surface of the intermediate insulating layer 48. By establishing such a contact angle relationship of water droplets representing hydrophilicity, the second liquid 32 does not spread on the wall portion 49 and reliably covers the first A insulating layer 47A or the first B insulating layer 47B. be able to. When the relationship of θ2 <θ3 is established, the direction defining means using EW described later functions more effectively.

  As shown in FIG. 13, the display cell 11A has a first A electrode 44 and a second electrode 46 with the second liquid 32 positioned on the first A insulating layer 47A (liquid sealed space S1). When a voltage is applied between them, EW that moves the second liquid 32 from the first A insulating layer 47A on the first A electrode 44 toward the intermediate insulating layer 48 having a larger layer thickness is used as shown by a solid arrow in FIG. The direction defining means thus functioned. Thereby, the second liquid 32 on the first A insulating layer 47A moves over the intermediate insulating layer 48 and moves onto the first B insulating layer 47B (liquid filled space S2) (FIG. 16A). When the applied voltage is stopped in this state, the intermediate insulating layer 48 acts as a liquid holding means, and the second liquid 32 that has moved onto the first B insulating layer 47B (the liquid sealing space S2) is held as it is, thereby exhibiting a memory property. (FIG. 16B).

  Further, when a voltage is applied between the first B electrode 45 and the second electrode 46, as shown by a chain line arrow in FIG. 14, the direction from the first B insulating layer 47B on the first B electrode 45 toward the thick intermediate insulating layer 48 is increased. The direction defining means using EW for moving the second liquid 32 functions. As a result, the second liquid 32 moves over the intermediate insulating layer 48 and moves onto the first A insulating layer 47A (liquid sealed space S1) (FIG. 16C). When the applied voltage is stopped in this state, the intermediate insulating layer 48 acts as a liquid holding means, and the second liquid 32 moved onto the first A insulating layer 47A (the liquid sealing space S1) is held as it is, and a memory property is developed. (FIG. 16D). In such a display cell 11A, ON / OFF display based on whether or not the second liquid 32 is located in the insulating layer (the first A insulating layer 47A in the illustrated example) of the portion (pixel portion 12) where the light shielding film 50 does not exist. Is possible.

  As described above, the intermediate insulating layer 48 that constitutes the display cell 11A constitutes a direction regulating means and is a liquid holding means. The height H at which the surface of the intermediate insulating layer 48 protrudes to the liquid sealing space S side than the surfaces of the first A insulating layer 47A and the first B insulating layer 47B is effective for the direction definition by EW, and the intermediate insulating The layer 48 is appropriately set in consideration of the wettability of the second liquid 32 with respect to the insulating material constituting the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48 so that the layer 48 functions as a liquid holding unit. be able to. For example, the height H can be set in the range of 0.01 to 1000 μm, preferably 1 to 100 μm. When the height H is less than 0.01 μm, the direction definition by EW does not function sufficiently, and the function of the intermediate insulating layer 48 as a liquid holding means may be insufficient. Further, when the height H exceeds 1000 μm, the intermediate insulating layer 48 becomes a barrier, and the first insulating layer 47A (liquid sealed space S1) and the first B insulating layer 47B (liquid sealed space S2) have a first wall. The driving voltage required for the movement of the second liquid 32 is undesirably high.

The base materials 42 and 43, the first A electrode 44, the first B electrode 45, and the second electrode 46 constituting the display cell 11A are the base materials 22 and 23, the first A electrode 24, the first B electrode 25, and the like in the above-described embodiment, respectively. This can be the same as that of the second electrode 26, and a description thereof is omitted here.
The insulating material forming the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48 that constitute the display cell 11A has the above-described water droplet contact angle magnitude relationship (θ1 <θ2 ≦ θ3). As long as it is established, it can be the same as the first A insulating layer 27A, the first B insulating layer 27B, and the narrow insulating layer 28 in the above-described embodiment, and the description thereof is omitted here. The insulating material constituting the first A insulating layer 47A and the first B insulating layer 47B and the insulating material constituting the intermediate insulating layer 48 may be the same or different. The thicknesses of the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48 are such that the first A electrode 44 and the first B electrode 45 can be electrically insulated from the first liquid 31 and the second liquid 32. And it can set suitably according to the insulating material to be used so that said protrusion height H can be ensured, for example, it can set in the range of 0.01-1000 micrometers.

Further, the wall portion 49 and the light shielding film 50 constituting the display cell 11A can be the same as the wall portion 29 and the light shielding film 30 in the above-described embodiment, respectively, and description thereof is omitted here.
The first liquid 31 sealed in the container 41 can be the same as the first liquid 31 sealed in the container 21 in the above-described embodiment.
On the other hand, the second liquid 32 sealed in the container 41 can be the same as the second liquid 32 sealed in the container 21 in the above-described embodiment, and the amount of the second liquid 32 is the first A insulating layer. 47A or the first B insulating layer 47B can be set as appropriate as the minimum amount for spreading over the entire area.
Further, in the present invention, the second liquid 32 can be colored oil, whereby information or the like can be displayed in a desired color.

When the display cell 11A is a transmissive display, the first liquid 31 can be a colored liquid and the second liquid 32 can be a light-shielding black oil. Thereby, ON / OFF display by two colors of the color which permeate | transmitted the colored liquid 31 and black is attained.
The display cell 11A is not limited to the structure described above. For example, a structure in which the substrate 42 side is the display recognition side and the light shielding film 50 is provided outside the substrate 42 may be employed. In this case, the base material 42 is a transparent base material, and the first A electrode 44, the first B electrode 45, the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48 are also transparent. Further, in the transmissive display, the substrate 43 and the second electrode 46 are also transparent. Further, the light shielding film 50 may not be provided, and the display may be based on a change in position due to the movement of the first liquid 31 and the second liquid 32.

  Further, as shown in FIG. 17, a structure in which the wall portion 49 is directly fixed to the base material 42 without the first A insulating layer 47 </ b> A and the first B insulating layer 47 </ b> B may be employed. Also in this case, the first A electrode 44 and the first B electrode 45 are covered with the first A insulating layer 47A, the first B insulating layer 47B, and the intermediate insulating layer 48, respectively, and are electrically connected from the first liquid 31 and the second liquid 32. Insulated. The insulating layers excluding the intermediate insulating layer 48 (the first A insulating layer 47A existing around the remaining portion of the first A electrode 44 and the first B insulating layer 47B existing around the remaining portion of the first B electrode 45) are formed as described above. Such direction-defining function (direction-defining function using EW that moves the second liquid 32 from the first A insulating layer 47A on the first A electrode 44 toward the intermediate insulating layer 48 having a larger layer thickness, and the first B The function of the direction defining means using EW for moving the second liquid 32 from the first B insulating layer 47B on the electrode 45 toward the intermediate insulating layer 48 having a larger layer thickness should not be hindered. Therefore, the surface of the first A insulating layer 47A existing around the first A electrode 44 and the surface of the first B insulating layer 47B existing around the first B electrode 45 are the first A insulating layer 47A on the first A electrode 44, The surface is the same as or lower than the surface of the first B insulating layer 47B on the first B electrode 45.

  Furthermore, in the present invention, as shown in FIG. 18, the intermediate insulating layer 48 may have a two-layer structure including an upper insulating layer 48 ′ and a lower insulating layer 48 ″. It is located at the boundary between the electrode 44 and the first B electrode 45 and covers a part of the first A electrode 44 and the first B electrode 45, and the upper insulating layer 48 'covers the lower insulating layer 48 ". In this case as well, the first A insulating layer 47A, the first B insulating layer 47B, and the upper insulating layer 48 ′ satisfy the above-described water droplet contact angle magnitude relationship (θ1 <θ2 ≦ θ3). The upper insulating layer 48 'may be made of the same material as or different from the first A insulating layer 47A and the first B insulating layer 47B. The relationship between the contact angles of water droplets representing the nature (θ1 <θ2 ≦ θ3) Without being, it is possible to use any of insulating material.

Further, the display cells constituting the display device of the present invention are not limited to the structure capable of displaying the numerical information “0” to “9” shown in FIG. For example, when the display cell is a reflective display, a plurality of display cells in which the colored oil as the second liquid is one of yellow, magenta, and cyan are arranged in a matrix or the like, and the reflective full color display It is good also as what performs. When the display cell is a transmissive display, the first liquid 31 is a colored liquid, the second liquid 32 is a light-shielding black oil, and the colored liquid 31 is any of red, green, and blue. A plurality of display cells may be arranged in a matrix or the like to perform transmissive full color display.
A plurality of unit cells having the same arrangement position and shape of the first A electrode 44 and the first B electrode 45 may be arranged in a matrix or the like. Thereby, for example, even if the light shielding film 50 does not exist, uniform display characteristics can be obtained in the entire display device.

[Display medium]
The display medium of the present invention has one or more display devices of the present invention described above, and has an input terminal for supplying power and signals from an external device to each display cell of the display device. The medium can be connected to and disconnected from an external device. Accordingly, even if the display medium is detached from the external device, the memory property can be maintained, so that information can be carried only by the display medium.

  FIG. 19 is a diagram for explaining an example of the display medium of the present invention. In FIG. 19, the display medium 60 of the present invention includes a display unit 61 in which a plurality of the above-described display devices of the present invention are arranged, and an input terminal 62. There is no limit to the number of display devices that constitute the display unit 61 of the display medium 60. Further, the arrangement position of the input terminal 62 is not particularly limited as long as it is a part around the display unit 61 (a part hatched in FIG. 19). The input terminal 62 is a terminal for supplying power and signals from the external device 70 to each display cell of the display device, and a connector 72 of the transmission means 71 linked to the external device 70 can be connected thereto. The display medium 60 can be connected to and disconnected from the external device 70 at the input terminal 62. Accordingly, power and signals are supplied from the external device 70 via the input terminal 62 to display desired information on the display medium 60, and then the connector 72 is removed from the input terminal 62, and the display medium 60 is removed from the external device 70. Can be detached and carried freely.

Examples of the external device 70 include computer means such as a personal computer and a mainframe computer, a telefacsimile machine, a copy machine, a data communication device such as a wireless communication device, a processing device, a network terminal, and an Internet terminal.
The transmission means 71 is not particularly limited, and can be supplied with electric power and signals such as an electric conductor cable and a hard wire link.
Each above-mentioned embodiment is an illustration and the present invention is not limited to these embodiments.

Next, the present invention will be described in more detail by showing more specific examples.
[Example 1]
First, a rectangular area (vertical 20 mm × width 10 mm) for forming a display device composed of seven display cells shown in FIG. 20A is set on a glass substrate (Corning 7059 glass) having a thickness of 700 μm. In addition, seven display cell areas were set. In addition, the pixel portion of each display cell was set to be a 6 mm × 5 mm rectangle (a part shaded in FIG. 20A).

In each of the seven display cells, a region for forming the first A electrode and the electrode non-formation region (the hatched portion in FIG. 20B) was set so as to include the pixel portion. Furthermore, a region for forming the first B electrode and the electrode non-formation region (a portion hatched in FIG. 20C) was set. Here, the electrode non-formation regions in each of the seven display cells were set as shown in FIG. 3 along the sides indicated by the arrows in FIGS. 20 (B) and 20 (C). 20 (B) and 20 (C), the area ratio between the first A electrode and the electrode non-formation region, and the first B electrode and no electrode non-formation are determined. The area ratio with the region was set to be seven types of 150: 1, 100: 1, 20: 1, 4: 1, 3: 1, 1: 1, and 1: 2.
Note that the distance between the region for forming the first A electrode and the electrode non-forming region and the region for forming the first B electrode and the electrode non-forming region in one display cell (corresponding to L in FIG. 4). Was 500 μm.

Further, in each of the seven display cells, a region for forming the first A insulating layer and the first B insulating layer so as to cover the first A electrode, the first B electrode, and the electrode non-forming region, the first A insulating layer And a region for forming a narrow insulating layer connecting the first B insulating layers. In FIG. 20D, the set formation regions of the first A insulating layer, the first B insulating layer, and the narrow insulating layer are hatched.
Next, a Cr film (thickness 1500 mm) is formed on the glass substrate by vapor deposition, and a photosensitive resist (Micro Posit manufactured by Shipley Co., Ltd.) is applied on the Cr film to a thickness of 0.8 μm by spin coating. Pre-baked at 90 ° C. for 3 minutes, exposed in a predetermined pattern (100 mJ / cm ² ), and then subjected to spray development using a 0.05% KOH aqueous solution for 60 seconds, and then at 200 ° C., 30 A resist film was formed by post-baking under conditions of minutes. Next, using this resist film as a mask, the Cr film was etched (etching solution: mixed solution of sulfuric acid and hydrogen peroxide) to form the first A electrode and the first B electrode for each display cell. A wiring (not shown in FIG. 20) for connecting the first A electrode and the first B electrode of each display cell to an external voltage application device was also formed at the same time.

Next, an insulating resin (amorphous fluororesin Teflon AF1601S manufactured by Mitsui DuPont Fluoro Chemical Co., Ltd.) is printed by a screen printing method so as to cover the first A electrode and the first B electrode of the glass substrate, and is heated at 100 ° C. By heating for 10 minutes, a 1 A insulating layer and a 1 B insulating layer having a thickness of 0.8 μm and a narrow insulating layer connecting them were formed. The formed narrow insulating layer had a length L of 0.5 mm and a width W of 1 mm (see FIG. 4). The contact angle of water droplets representing the hydrophilicity of the surfaces of the first A insulating layer, the first B insulating layer, and the narrow insulating layer was about 115 °. The contact angle is measured by dropping one drop (fixed amount) of pure water (distilled water for liquid chromatography (manufactured by Junsei Chemical Co., Ltd.)) on the surface of the object to be measured. (Kyowa Interface Chemical Co., Ltd. CA-Z) was used according to the θ / 2 method. The same applies to the following examples and comparative examples.
Next, on the boundary line of each display cell and on the outer peripheral edge of the rectangular region for forming the display device, a UV-curable resin containing beads (LCB-610 manufactured by EHC Co.) is used, and the width is 1 mm. A wall having a thickness of 200 μm was formed.

On the other hand, on the other glass substrate (Corning 7059 glass) having a thickness of 700 μm, the same rectangular region for forming the display device and the pixel portion of each display cell were set. An indium tin oxide (ITO) film was formed on one surface of the glass substrate by a vapor deposition method so as to coincide with the rectangular region for forming the display device, thereby forming a second electrode (common electrode). A wiring (not shown) for connecting the second electrode to an external voltage applying device was also formed at the same time.
Next, on the other surface of the 700 μm thick glass substrate, a light-shielding resin material having the following composition was applied to a thickness of 5 μm by spin coating, and prebaked at 90 ° C. for 3 minutes. Exposure (100 mJ / cm ² ) with a predetermined pattern, followed by spray development using a 0.05% KOH aqueous solution for 60 seconds, followed by post-baking at 200 ° C. for 30 minutes to form a light-shielding film Formed. The light-shielding film is opposed to the second electrode through the glass substrate, and the seven pixel portions are exposed.

(Light-shielding resin composition)
・ Black pigment: 14 parts by weight (TM Black # 95550, manufactured by Dainichi Seika Kogyo Co., Ltd.)
・ Dispersant: 1.2 parts by weight (Disperbyk 111 manufactured by Big Chemie Co., Ltd.)
-Polymer (VR60 manufactured by Showa Polymer Co., Ltd.) ... 2.8 parts by weight-Monomer (SR399 manufactured by Sartomer Co., Ltd.) ... 3.5 parts by weight-Initiator ... 1.6 parts by weight (2-Benzyl-2- Dimethylamino-1- (4-morpholinophenyl)
-Butanone-1)
Initiator (4,4′-diethylaminobenzophenone) 0.3 parts by weight Initiator (2,4-diethylthioxanthone) 0.1 parts by weight Solvent (ethylene glycol monobutyl ether) 75.8 parts by weight

Next, the surface on which the second electrode of the 700 μm thick glass substrate is formed is pressure-bonded so as to come into contact with the wall portion of the glass substrate on which the first A insulating layer, the first B insulating layer, the narrow insulating layer, etc. are formed. Thereafter, the wall portion was irradiated with ultraviolet rays (60 mW / cm ² , 5 minutes) to be cured. In this pressure bonding, first, water and oil (dodecane is used as a blue dye (OilBlue manufactured by Arimoto Chemical Co., Ltd.) in each display cell of a glass substrate on which a 1A insulating layer, a 1B insulating layer, a narrow insulating layer, etc. are formed. 5502) was filled so that the volume ratio was 50: 1, and the display cell positions of the two glass substrates were aligned. The contact angle of water droplets representing the hydrophilicity of the wall after being cured in this manner was about 55 °.

As a result, seven types of display devices as shown in FIG. 2 were produced. In this display device, as described above, the contact angle of water droplets representing the hydrophilicity of the wall portion is about 55 °, and the contact of water droplets representing the hydrophilicity of the surfaces of the first A insulating layer, the first B insulating layer, and the narrow insulating layer. The angle was about 115 °.
With respect to the seven types of display devices thus produced, when a DC voltage of 40 V was applied between the first A electrode and the second electrode (common electrode) of all the display cells, the first A electrode and the electrode under the first A insulating layer In the five types of display devices except for the display device in which the area ratio to the non-formation region and the area ratio between the first B electrode and the electrode non-formation region under the first B insulating layer is 150: 1 and the display device of 1: 2. The oil (colored dodecane) moved onto the 1B insulating layer via the narrow insulating layer. As a result, when observed from the side of the glass substrate on which the light shielding film was formed, outside light was reflected by the Cr film constituting the first A electrode in all the seven pixel portions, and the numeral “8” was displayed. Further, when the applied voltage was stopped in this state, the same display state was maintained for 10 days or more, and it was confirmed that it had excellent memory properties.

In the above five types of display devices, when a DC voltage of 40 V is applied between all the first B electrodes and the second electrodes (common electrodes), oil (colored dodecane) passes through the narrow insulating layer. Then, it moved onto the 1B insulating layer, the blue color of oil (colored dodecane) was recognized in the pixel portion, and the number “8” was displayed. When the applied voltage was stopped in this state, the same display state was maintained for 10 days or more, and it was confirmed that it had excellent memory properties.
Furthermore, the five types of display devices described above appropriately reflect the light or oil (colored) by appropriately setting the first A electrode or the first B electrode that applies a DC voltage to the second electrode (common electrode). Any number of “0” to “9” in blue of dodecane) could be displayed. Also in this case, it was confirmed that it had excellent memory properties.

However, in the display device in which the area ratio between the first A electrode and the electrode non-formation region and the area ratio between the first B electrode and the electrode non-formation region is 150: 1, the first A electrode and the second electrode of all the display cells Even if a 40V DC voltage is applied to the (common electrode), the direction defining means using EW does not function sufficiently, and oil (colored dodecane) remains on the first A insulating layer, and the applied voltage It was the same even when the voltage was increased from 40V to 100V.
In the display device in which the area ratio between the first A electrode and the electrode non-formation region and the area ratio between the first B electrode and the electrode non-formation region is 1: 2, the first A electrode and the second electrode of all the display cells. The oil (colored dodecane) moves to the first B insulating layer through the narrow insulating layer only after the voltage applied to the common electrode reaches 80 V, compared with the above five types of display devices. It was confirmed that a high drive voltage was necessary.

[Example 2]
As in Example 1, a rectangular region (vertical 20 mm × horizontal) for forming a display device composed of seven display cells shown in FIG. 20A on a 700 μm thick glass substrate (Corning 7059 glass). 10 mm) and 7 display cell areas were set. In addition, the pixel portion of each display cell was set to be a 6 mm × 5 mm rectangle (a part shaded in FIG. 20A).
In each of the seven display cells, a region for forming the first A electrode (a portion hatched in FIG. 20B) was set so as to include the pixel portion. Furthermore, a region for forming the first B electrode (a portion hatched in FIG. 20C) was set. In each of the seven display cells, between the first A electrode and the first B electrode,
Note that the interval (corresponding to W3 in FIG. 14) between the region for forming the first A electrode and the region for forming the first B electrode in one display cell was 150 μm.

Next, in the same manner as in Example 1, a first A electrode and a first B electrode were formed for each display cell on a glass substrate having a thickness of 700 μm.
Next, an insulating resin (amorphous fluororesin Teflon AF1601S manufactured by Mitsui DuPont Fluoro Chemical Co., Ltd.) is printed by a screen printing method so as to cover the first A electrode and the first B electrode of the glass substrate, and is heated at 100 ° C. An insulating layer having a thickness of 0.8 μm was formed over the entire area by heating for 10 minutes (the insulating layer on the 1A electrode was the 1A insulating layer and the insulating layer on the 1B electrode was the 1B insulating layer). . The contact angle of water droplets representing the hydrophilicity of the surfaces of the first A insulating layer and the first B insulating layer insulating layer was about 115 °.

Further, an insulating resin (amorphous fluororesin Teflon AF1601S manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) is printed on the insulating layer located between the first A electrode and the first B electrode of each display cell by a screen printing method. Then, it was heated in an oven at 100 ° C. for 10 minutes to form an intermediate insulating layer. The width of the intermediate insulating layer is 200 μm, and is positioned on the insulating layer located between the first A electrode and the first B electrode, and the first A insulating layer on the first A electrode and the first B on the first B electrode. Each of the intermediate insulating layers was 25 μm on the insulating layer, and the surface of the intermediate insulating layer protruded 5 μm from the first A insulating layer on the 1A electrode and the 1B insulating layer on the 1B electrode. The contact angle of water droplets representing the hydrophilicity of the surface of the intermediate insulating layer was about 115 °.
Next, on the boundary line of each display cell and on the outer peripheral edge of the rectangular region for forming the display device, a UV-curable resin containing beads (LCB-610 manufactured by EHC Co.) is used, and the width is 1 mm. A wall having a thickness of 200 μm was formed.

On the other hand, in order to connect the second electrode (common electrode) and the second electrode to an external voltage applying device on another glass substrate (Corning 7059 glass) having a thickness of 700 μm in the same manner as in Example 1. Wiring (not shown) was formed at the same time. Next, a light shielding film was formed on the other surface of the glass substrate in the same manner as in Example 1.
Next, the surface on which the second electrode of the 700 μm thick glass substrate is formed is pressure-bonded so as to contact the wall portion of the glass substrate on which the first A insulating layer, the first B insulating layer, the intermediate insulating layer, etc. are formed. In the same manner as in Example 1, two glass substrates were bonded. The contact angle of water droplets representing the hydrophilicity of the walls after joining was about 55 °.
Thus, a display device as shown in FIG. 13 was produced. In this display device, as described above, the contact angle of water droplets representing the hydrophilicity of the wall is about 55 °, and the contact angle of water drops representing the hydrophilicity of the first A insulating layer, the first B insulating layer, and the intermediate insulating layer is about 55 °. It was 115 °.
About the produced display apparatus, similarly to Example 1, the display performance was evaluated by appropriately setting the first A electrode or the first B electrode for applying a DC voltage to the second electrode (common electrode). As a result, it is possible to display any number from “0” to “9” in blue of reflected light or oil (colored dodecane), and even if the applied voltage is stopped, the same display state is 10 It was confirmed that it was retained for more than a day and had excellent memory properties.

[Example 3]
In the same manner as in Example 2, a first A electrode and a first B electrode were formed for each display cell on a glass substrate having a thickness of 700 μm.
Next, a photocurable resin composition (Optomer NN series manufactured by JCR Corporation) is applied by spin coating, pre-baked at 90 ° C. for 3 minutes, and exposed in a predetermined pattern (100 mJ / cm ² ). After that, spray development using 0.05% KOH aqueous solution is performed for 60 seconds, and then post-baked at 200 ° C. for 30 minutes, so that the lower part having a width of 200 μm is formed between the first A electrode and the first B electrode. An insulating layer (thickness 4 μm) was formed. The lower insulating layer was obtained by riding 25 μm on each of the first A electrode and the first B electrode. The contact angle of water droplets representing the hydrophilicity of the lower insulating layer was about 80 °.

Next, an insulating resin (amorphous fluororesin Teflon AF1601S manufactured by Mitsui DuPont Fluoro Chemical Co., Ltd.) is printed by a screen printing method so as to cover the first A electrode and the first B electrode of the glass substrate. Insulating layer having a thickness of 0.8 μm over the entire area by heating for 10 minutes (the insulating layer on the 1A electrode is the 1A insulating layer, the insulating layer on the 1B electrode is the 1B insulating layer, on the lower insulating layer) The insulating layer is an upper insulating layer). And the lamination | stacking site | part of a lower insulating layer and an upper insulating layer comprises an intermediate | middle insulating layer, and the surface of this intermediate | middle insulating layer is more than the 1A insulating layer on the 1A electrode, and the 1B insulating layer on the 1B electrode It became what protruded 4.8 micrometers. The contact angle of water droplets representing the hydrophilicity of the surfaces of the first A insulating layer, the first B insulating layer insulating layer, and the intermediate insulating layer was about 115 °.
Next, on the boundary line of each display cell and on the outer peripheral edge of the rectangular region for forming the display device, a UV-curable resin containing beads (LCB-610 manufactured by EHC Co.) is used, and the width is 1 mm. A wall having a thickness of 200 μm was formed.

On the other hand, in order to connect the second electrode (common electrode) and the second electrode to an external voltage applying device on another glass substrate (Corning 7059 glass) having a thickness of 700 μm in the same manner as in Example 1. Wiring (not shown) was formed at the same time. Next, a light shielding film was formed on the other surface of the glass substrate in the same manner as in Example 1.
Next, the surface on which the second electrode of the 700 μm thick glass substrate is formed is pressure-bonded so as to contact the wall portion of the glass substrate on which the first A insulating layer, the first B insulating layer, the intermediate insulating layer, etc. are formed. In the same manner as in Example 1, two glass substrates were bonded. The contact angle of water droplets representing the hydrophilicity of the wall portion after bonding was about 55 °.
Thus, a display device as shown in FIG. 18 was produced. In this display device, as described above, the contact angle of water droplets representing the hydrophilicity of the wall is about 55 °, and the contact angle of water drops representing the hydrophilicity of the first A insulating layer, the first B insulating layer, and the intermediate insulating layer is about 55 °. It was 115 °.

  About the produced display apparatus, similarly to Example 1, the display performance was evaluated by appropriately setting the first A electrode or the first B electrode for applying a DC voltage to the second electrode (common electrode). As a result, it is possible to display any number from “0” to “9” in blue of reflected light or oil (colored dodecane), and even if the applied voltage is stopped, the same display state is 10 It was confirmed that it was retained for more than a day and had excellent memory properties.

[Comparative Example 1]
The area ratio between the first A electrode and the electrode non-formation region, and the area ratio between the first B electrode and the electrode non-formation region were set to 4: 1, and the polyimide resin (ALSR 1254 manufactured by JSR Corporation) was used. 1A insulating layer, 1B insulating layer and narrow insulating layer (contact angle of water droplets representing hydrophilicity is about 65 °), and UV-curable resin containing beads (XN-50 manufactured by Mitsui Chemicals, Inc.) A display device as shown in FIG. 2 was produced in the same manner as in Example 1 except that the wall (the contact angle of water droplets representing hydrophilicity after curing was about 80 °) was formed using
About the produced display apparatus, similarly to Example 1, the display performance was evaluated by appropriately setting the first A electrode or the first B electrode for applying a DC voltage to the second electrode (common electrode). As a result, the oil (colored dodecane) easily covered the wall portion and did not spread sufficiently on the first A insulating layer and the first B insulating layer, and stable display could not be performed even when a voltage was applied.

[Comparative Example 2]
Further, an intermediate insulating layer having a width of 150 μm is provided on the insulating layer located between the first A electrode and the first B electrode of each display cell, and the surface of the intermediate insulating layer is the first A insulating layer on the first A electrode. A display device as shown in FIG. 13 was fabricated in the same manner as in Example 2 except that the same surface as the first B insulating layer on the first B electrode was formed.
About the produced display apparatus, similarly to Example 1, the display performance was evaluated by appropriately setting the first A electrode or the first B electrode for applying a DC voltage to the second electrode (common electrode). As a result, even if a DC voltage of 40V is applied between the first A electrode and the second electrode (common electrode) of all the display cells, the direction defining means using EW does not function sufficiently, and the 1A insulation It was the same even if the oil (colored dodecane) remained on the layer and the applied voltage was increased from 40V to 100V.

  The present invention can be used for display devices that require memory.

It is a top view which shows an example of the display apparatus of this invention. FIG. 2 is an enlarged vertical sectional view taken along line II of the display device shown in FIG. 1 and shows the structure of one display cell. FIG. 3 is a plan view showing a first A electrode and a first B electrode of the display cell shown in FIG. 2. FIG. 3 is a plan view showing a first A insulating layer and a first B insulating layer of the display cell shown in FIG. 2. It is a figure for demonstrating the display operation of the display apparatus of this invention. It is a top view which shows the other example of the 1st A electrode and 1st B electrode of the display apparatus of this invention. It is a top view which shows the other example of the 1A insulating layer and 1B insulating layer of the display apparatus of this invention. It is a top view which shows the other example of the 1st A electrode and 1st B electrode of the display apparatus of this invention. It is a top view which shows the other example of the 1st A electrode and 1st B electrode of the display apparatus of this invention. It is a top view which shows the other example of the 1A insulating layer and 1B insulating layer of the display apparatus of this invention. It is a longitudinal cross-sectional view equivalent to FIG. 2 which shows the other example of the display apparatus of this invention, and shows the structure of one display cell. It is a longitudinal cross-sectional view equivalent to FIG. 2 which shows the other example of the display apparatus of this invention, and shows the structure of one display cell. It is a longitudinal cross-sectional view equivalent to FIG. 2 which shows the other example of the display apparatus of this invention, and shows the structure of one display cell. FIG. 14 is a plan view showing a first A electrode and a first B electrode of the display cell shown in FIG. 13. FIG. 14 is a plan view showing a first A insulating layer and a first B insulating layer of the display cell shown in FIG. 13. It is a figure for demonstrating the display operation of the display apparatus of this invention. It is a longitudinal cross-sectional view equivalent to FIG. 2 which shows the other example of the display apparatus of this invention, and shows the structure of one display cell. It is a longitudinal cross-sectional view equivalent to FIG. 2 which shows the other example of the display apparatus of this invention, and shows the structure of one display cell. It is a figure which shows an example of the display medium of this invention. It is a figure for demonstrating manufacture of the display apparatus in an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Display apparatus 11 (11A, 11B, 11C, 11D, 11E, 11F) ... Display cell 12 ... Pixel part 13 ... Space part 21, 41 ... Container 22, 23, 42, 43 ... Base material 24, 44 ... 1A Electrode (first electrode)
25, 45 ... 1B electrode (first electrode)
26, 46, 66 ... second electrode 27A, 47A ... 1A insulation layer 27B, 47B ... 1B insulation layer 28 ... narrow insulation layer 48 ... intermediate insulation layer 48 '... upper insulation layer 48 "... lower insulation layer 29, DESCRIPTION OF SYMBOLS 49 ... Wall part 30, 50 ... Light-shielding film 31 ... 1st liquid 32 ... 2nd liquid 60 ... Display medium 61 ... Display part 62 ... Input terminal 70 ... External device

Claims (11)

A container having at least a first electrode and a second electrode and enclosing therein a first liquid and a second liquid that are not mixed with each other, and any one of the first electrode and the second electrode is the first electrode And the first liquid has conductivity or polarity, and the voltage is applied to one or both of the first electrode and the second electrode by applying a voltage to the first liquid and the second liquid. In a display device including at least one display cell capable of displaying by changing the positions of the first liquid and the second liquid,
The container includes a pair of base materials, at least one of which is a transparent base material, a wall portion that holds the pair of base materials facing each other so as to form a liquid enclosure space, and the liquid of the one base material. A first A electrode and a first B electrode disposed electrically independently from each other on the enclosing space side; a first A insulating layer and a first B insulating layer covering the first A electrode and the first B electrode; A narrow insulating layer connecting the insulating layer and the first B insulating layer, and a second electrode disposed on the other substrate side of the liquid enclosure space, the first A insulating layer and the first B insulating layer Of these, the non-electrode-forming regions where the first A electrode and the first B electrode do not exist are provided in the adjacent regions connected by the narrow insulating layer, and the first A electrode and the first B electrode are the first liquid. And the second liquid is electrically insulated from the first A electrode and the second liquid. The second liquid is applied to the first A insulating layer and the first B insulating layer via the narrow insulating layer by an applied voltage between the electrodes or an applied voltage between the first B electrode and the second electrode. The narrow insulating layer is movable between the first liquid and the second liquid after the applied voltage is stopped at the position where the first liquid and the second liquid are moved. Liquid holding means for maintaining the position of the liquid and exhibiting a memory property, wherein the narrow insulating layer is on the first A insulating layer or the first B insulating layer when the applied voltage is stopped A contact angle θ1 of a water droplet having a width and a length at which the second liquid located at a position where the second liquid cannot move and which is exposed in the container of the wall portion, and the first A insulating layer and the first B Shows the contact angle θ2 of the water droplet, which represents the hydrophilicity of the surface of the insulating layer, and the hydrophilicity of the surface of the narrow insulating layer Relationship θ1 <θ2 ≦ θ3 between the contact angle .theta.3 of the water droplet is satisfied, the area ratio of the first 1A electrode and the electrode non-formation region, the area ratio of the first 1B electrode and the electrode non-formation region , 100: 1 to 1: 1, the width of the narrow insulating layer in the range of 0.01～10000Myuemu, length display device comprising range der Rukoto of 0.01～1000Myuemu. A container having at least a first electrode and a second electrode and enclosing therein a first liquid and a second liquid that are not mixed with each other, and any one of the first electrode and the second electrode is the first electrode And the first liquid has conductivity or polarity, and the voltage is applied to one or both of the first electrode and the second electrode by applying a voltage to the first liquid and the second liquid. In a display device including at least one display cell capable of displaying by changing the positions of the first liquid and the second liquid,
The container includes a pair of base materials, at least one of which is a transparent base material, a wall portion that holds the pair of base materials facing each other so as to form a liquid enclosure space, and the liquid of the one base material. A first A electrode and a first B electrode disposed electrically independently from each other on the enclosing space side; a first A insulating layer and a first B insulating layer covering the first A electrode and the first B electrode; An intermediate insulating layer connecting the insulating layer and the first B insulating layer; and a second electrode disposed on the other substrate side of the liquid-filled space. The intermediate insulating layer includes a first A electrode and a first B electrode. The intermediate insulating layer is positioned at a boundary portion between the first A electrode and the first B electrode so as to cover a part of the first insulating layer, and the surface of the intermediate insulating layer is closer to the liquid enclosure space than the surfaces of the first A insulating layer and the first B insulating layer. The first A electrode and the first B electrode are formed from the first liquid and the second liquid. A second liquid is applied to the intermediate insulating layer by an applied voltage between the first A electrode and the second electrode or an applied voltage between the first B electrode and the second electrode. It is possible to move over the first A insulating layer and the first B insulating layer, and the intermediate insulating layer stops the applied voltage at the position where the first liquid and the second liquid move. And a liquid holding means for maintaining the moved position of the first liquid and the second liquid so as to develop a memory property, wherein the surface of the intermediate insulating layer is the first A insulating layer and the first B The height of the insulating layer protruding from the surface of the liquid enclosure space is such that when the applied voltage is stopped, the second liquid located on the first A insulating layer or the first B insulating layer is The height of the wall that cannot be overcome and exposed in the container of the wall The contact angle θ1 of the water droplet representing the hydrophilicity of the water, the contact angle θ2 of the water droplet representing the hydrophilicity of the surfaces of the first A insulating layer and the first B insulating layer, and the contact angle of the water droplet representing the hydrophilicity of the surface of the intermediate insulating layer The relationship θ1 <θ2 ≦ θ3 is established between θ3 and the area ratio between the first A electrode without the intermediate insulating layer and the intermediate insulating layer covering the first A electrode, and the intermediate insulating layer exists. The area ratio of the first B electrode and the intermediate insulating layer covering the first B electrode is in the range of 100: 1 to 1: 1, and the surface of the intermediate insulating layer is the first A insulating layer and the first B height than the surface of the insulating layer protrudes into the liquid confining space side display device comprising range der Rukoto of 1 to 100 [mu] m. The intermediate insulating layer includes a lower insulating layer positioned at a boundary portion between the first A electrode and the first B electrode, and an upper insulating layer positioned on the lower insulating layer. The upper insulating layer includes the first A insulating layer and the first insulating layer. The display device according to claim 2 , wherein the display device is made of the same material as the first B insulating layer . The display device according to claim 3 , wherein the lower insulating layer is thicker than the first A electrode and the first B electrode. Display device according to any one of claims 1 to 4, characterized in that the outer side of the transparent substrate of the display recognize side comprising a light-shielding film in a desired pattern shape. Display device according to any one of claims 1 to 5, wherein the second liquid is a colored oil. It is a reflection type display that recognizes light reflected in the display cell, and the colored oil that is the second liquid sealed in each display cell is one of yellow, magenta, and cyan. The display device according to claim 6 . It is a transmissive display that recognizes light transmitted through the display cell, wherein the first liquid is colored water, and the colored oil that is the second liquid is light-shielding black oil. The display device according to claim 6 . The display device according to claim 8 , wherein the colored water that is the first liquid sealed in each display cell is one of red, green, and blue. Display device according to any one of claims 1 to 9 the shape and position of the first 1A electrode and the second 1B electrode of each of the display cells, characterized in that the same. 11. One or more display devices according to any one of claims 1 to 10 , comprising an input terminal for supplying power and signals from an external device to each display cell of the display device, the input terminal A display medium characterized in that the display medium and the external device can be connected and disconnected.

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