JP2010122706A - Display and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display and an electronic apparatus including the display which has long life reliability by preventing poor conduction caused by exfoliation between a substrate and a conductive material. <P>SOLUTION: The display 1 includes a first substrate 3, a second substrate 5, and microcapsules 6 sandwiched between the first substrate 3 and the second substrate 5, the microcapsules 6 constituting a display area 9, the microcapsules encapsulating a display material whose optical properties change in response to electrical stimulation. A conductive material 8 for conducting between the substrates is provided between the first substrate 3 and the second substrate 5 to constitute a vertically conducting portion 12. The thickness of the conductive material 8 is set such that the distance W1 between the first substrate 3 and the second substrate 5 at the vertically conducting portion 12 is larger than the distance W2 between the first substrate 3 and the second substrate 5 in the display area 9. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device including a microcapsule and an electronic device including the display device.

  Conventionally, an electrophoretic dispersion liquid including a liquid phase dispersion medium and electrophoretic particles is included, and by applying an electric field, the distribution state of the electrophoretic particles changes and the optical characteristics of the electrophoretic dispersion liquid change. An electrophoretic display device utilizing this fact is known (for example, see Patent Document 1). Since such an electrophoretic display device does not require a backlight, it is possible to reduce the cost and thickness, and in addition to having a wide viewing angle and high contrast, and having a display memory property, the next generation Has attracted attention as a display device.

  In such an electrophoretic display device, an electrophoretic dispersion liquid is enclosed in a microcapsule, and the microcapsule is interposed between a transparent substrate having a transparent electrode serving as a common electrode and a substrate having a pixel electrode, for example. What is pinched is known. By encapsulating the electrophoretic dispersion liquid in the microcapsules, there is an advantage that the dispersion liquid can be prevented from flowing out in the manufacturing process of the display device, and sedimentation and aggregation of the electrophoretic particles can be reduced.

  By the way, in an electrophoretic display device provided with such a microcapsule, a method using a conductive material containing conductive particles in a resin is generally employed as a method for establishing conduction between the transparent electrode and the substrate. Has been. Examples of the conductive material include a conductive paste in which conductive particles such as metal particles such as silver and carbon particles are mixed and contained in a resin such as epoxy, and a conductive sheet obtained by processing this conductive paste into a sheet shape. Are known.

  When conducting between the substrates using such a conductive material, the spacing between the substrates in the display region formed by the microcapsules and the conduction are prevented in order to prevent color unevenness and the like from occurring. The thickness (height) of the conductive material is set so that the distance between the substrates in the vertical conductive part that is made conductive by the material is the same, and the vertical conductive part is formed.

JP-A-9-185087

  However, in the display device having the above-described structure, when a reliability test such as a high temperature standing or a temperature cycle is performed, the transparent substrate or the substrate and the conductive material are peeled off due to thermal expansion and contraction of the resin in the conductive material. May occur, resulting in poor continuity. When a continuity failure occurs in such a reliability test, it is predicted that the product does not have long-term reliability when it is put on the market, and therefore a countermeasure is strongly demanded.

  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 that prevents poor conduction due to peeling between the substrate and the conductive material and ensures long-term reliability. It is providing the electronic device provided with.

In order to achieve the above object, a display device of the present invention includes a first substrate, a second substrate, and a microcapsule that is sandwiched between the first substrate and the second substrate to form a display region. A display material whose optical characteristics change in response to electrical stimulation is enclosed in the microcapsule,
Between the first substrate and the second substrate, a conductive material for conducting between these substrates is provided to form a vertical conduction portion,
The conductive material has a thickness that makes the interval between the first substrate and the second substrate in the vertical conduction part wider than the interval between the first substrate and the second substrate in the display region. It is characterized by being provided.

  According to this display device, the interval between the first substrate and the second substrate in the vertical conduction portion is made wider than the interval between the first substrate and the second substrate in the display region. Since the thickness of the conductive material is set and provided, the first substrate and / or the second substrate are warped outward in the vertical conductive portion and elastically deformed with respect to the display region. Therefore, the first substrate and / or the second substrate exerts a force acting on the inside in the vertical conduction portion, that is, a force pressing the conduction material side, particularly by the elastic restoring force. Therefore, since the first substrate and / or the second substrate always presses the conductive material side in this way, the first substrate can be obtained even when a reliability test such as a high temperature standing or a temperature cycle is performed. Alternatively, peeling between the second substrate and the conductive material is prevented, thereby ensuring long-term reliability as a product.

Further, in the display device, the conductive material is arranged such that an interval between the first substrate and the second substrate in the vertical conductive portion is determined, and the first substrate and the second substrate in the display region. It is preferable that the thickness be larger in the range of 10 μm or more and 200 μm or less than the distance between the two.
If the distance between the substrates in the upper and lower conductive parts is less than 10 μm, the pressing force to the conductive material side due to the elastic restoring force is low, and peeling may occur in the reliability test. Exceeding may cause microcapsules located in the vicinity of the upper and lower conductive portions to peel off from the substrate due to changes over time over a long period of time, which may cause display defects. Therefore, as described above, by setting the range of 10 μm or more and 200 μm or less, it is possible to ensure both the long-term reliability related to the conduction failure and the long-term reliability related to the display failure.

In the display device, it is preferable that the vertical conduction portion is disposed on the outer periphery of the first substrate and the second substrate.
In this way, the elastic return force works more strongly, so that the force that presses the conductive material side is better exhibited.

Further, in the display device, the first substrate and the second substrate are located between the first substrate and the second substrate at positions different from the vertical conduction portion and the display region. It is preferable to provide an adhesive layer for fixing the two.
In this way, the first substrate and the second substrate are more firmly bonded to each other, thereby preventing separation between the substrate and the conductive material.

In this display device, a substrate electrode is formed on one of the first substrate and the second substrate at a position including the vertical conductive portion, and the adhesive layer is formed of the vertical conductive portion. It is preferable to be provided on a substrate electrode other than the above.
In this way, in particular, the adhesion between the substrate electrode and the conductive material can be reinforced by the adhesive layer.

In the display device, it is preferable that the adhesive layer is provided between the microcapsule and the vertical conduction portion.
In this way, the first substrate and the second substrate can be bonded together in the vicinity of the vertical conduction portion in addition to the bonding between the first substrate and the second substrate more firmly. Peeling of the vertical conduction part with respect to the substrate is also prevented.

In this display device, the microcapsule is bonded to the first substrate or the second substrate, and the adhesive of the adhesive layer attaches the microcapsule to the first substrate or the second substrate. It is preferable to be the same as the adhesive that adheres to the substrate.
In this way, the adhesive layer can be formed simultaneously with the step of sandwiching the microcapsules, and thus the manufacturing process is advantageous.

Further, the microcapsule is bonded to the first substrate or the second substrate with an adhesive sheet having a thickness of 25 μm or more, and the adhesive of the adhesive layer is such that a part of the adhesive sheet is vertically conductive. It is preferable that it is formed by protruding to the part side.
In this way, by heating an adhesive sheet having a thickness of 25 μm or more, it softens and a part of the adhesive sheet protrudes to the vertical conduction part side and hardens in that state, thereby forming an adhesive layer. Therefore, it is possible to form an adhesive layer without adding a new process, which is extremely advantageous in terms of the manufacturing process.

Further, in this display device, the adhesive layer is made of a moisture-proof resin, and is disposed outside the vertical conduction part and the display area so as to surround the vertical conduction part and the display area. preferable.
In this way, it is possible to prevent corrosion of the electrode and deterioration of the microcapsules due to moisture (moisture).

An electronic apparatus according to the present invention includes the display device described above.
According to this electronic device, since the display device with the long-term reliability is provided, the electronic device itself also has the long-term reliability.

It is a sectional side view which shows schematic structure of one Embodiment of the display apparatus of this invention. It is a top view which shows the inner surface side of a 1st board | substrate. It is a top view which shows the inner surface side of a 1st board | substrate. (A)-(d) is a figure for demonstrating the manufacturing method of a display apparatus to process order. It is a schematic block diagram for demonstrating other embodiment of the display apparatus of this invention. 1 is a perspective view illustrating an external configuration of a computer that is an example of an electronic apparatus according to the invention. 1 is a perspective view illustrating an external configuration of a mobile phone that is an example of an electronic apparatus of the present invention. 1 is a perspective view illustrating an external configuration of electronic paper that is an example of an electronic apparatus of the present invention. 1 is a perspective view illustrating an external configuration of an electronic notebook that is an example of the electronic apparatus of the invention.

The present invention will be described in detail below.
FIG. 1 is a diagram showing an embodiment of a display device of the present invention, and reference numeral 1 in FIG. 1 is a display device. In FIG. 1 and FIG. 4, in order to make the characteristic part of the present invention easier to understand, dimensions and shapes are extremely described and schematically shown compared to actual ones. In particular, the microcapsules are described so that their diameters are different between the center side and both sides, but in reality, all are formed to have substantially the same diameter.

  The display device 1 includes a first substrate 3 having a plurality of pixel electrodes 2 and a second substrate 5 having a common electrode (counter electrode) 4, and these first substrates 3. And the second substrate 5 are sandwiched with a microcapsule 6 enclosing a display material. In such a display device 1, the display surface (observation surface) can be either one or both. In this case, the substrate and the electrode serving as the display surface are It is necessary for the light transmittance to be high, and it is particularly preferable that it is transparent. In the present embodiment, as described later, the second substrate 5 is a transparent substrate, and the common electrode 4 is a transparent electrode, whereby the second substrate 5 side is used as a display surface.

  A large number of pixel electrodes 2 are formed on the inner surface side of the first substrate 3, and wiring (not shown) such as a copper foil pattern connected to these pixel electrodes 2 is formed. A substrate electrode 7 is disposed on the outer periphery of the first substrate 3 outside the pixel electrode 2. The substrate electrode 7 is electrically connected to an external power source via, for example, an FPC (flexible printed wiring board), and is electrically connected to the second substrate 5 via the conductive material 8.

  As the first substrate 3 and the second substrate 5, the display device 1 has a rectangular shape, a film shape or a sheet, particularly when flexibility (flexibility) is required such as an IC card or electronic paper. Shaped resin substrate is used. In addition, as described above, the second substrate 5 that serves as the display surface (observation surface) is particularly transparent (having a high light transmittance) as described above. As a material of such a transparent substrate (second substrate 5), for example, polyethylene terephthalate (PET), polyethersulfone (PES), polycarbonate (PC), or the like is preferably used.

Further, since the first substrate 3 that does not become a display surface does not need to be transparent (highly light transmissive), other than the above materials, polyimide (PI), polyethylene naphthalate (PEN), etc. Polyester, polyethylene (PE), polystyrene (PS), polypropylene (PP), polyetheretherketone (PEEK), acrylic or polyacrylates can also be used.
In the case where flexibility (flexibility) is not required for a display device as in a general panel, a semiconductor substrate such as glass, hard resin, or silicon can be used.

  However, in the present invention, as will be described later, since at least one of the first substrate 3 and the second substrate 5 is elastically deformed and the elastic restoring force is exhibited in this state, At least one of the first substrate 3 and the second substrate 5 needs to be a flexible substrate that can be elastically deformed, and a material, a thickness, and the like are appropriately selected to have such properties. And used.

  In this embodiment, a polyimide substrate having a thickness of 25 μm is used as the first substrate 3, whereby the first substrate 3 has flexibility, and can be elastically deformed and elastically restored. . As shown in FIG. 2, a pair of substrate electrodes 7 are formed on the inner surface of the polyimide substrate (first substrate 3) on the outer side of the substrate, and a pixel electrode is interposed between the substrate electrodes 7 and 7. (Not shown) is formed. A display region 9 is formed corresponding to such a pixel electrode group as described later. The substrate electrode 7 is made of, for example, a copper foil pattern having a thickness of 10 to 20 μm formed by a semi-additive method.

  Here, as shown in FIG. 1, the pixel electrode 2 may be formed by a copper foil pattern in the same process as the formation of the substrate electrode 7, or, apart from the formation of the substrate electrode 7, aluminum ( You may form with common electrically-conductive materials, such as Al). Many of these pixel electrodes 2 are arranged in a pre-designed state corresponding to a pixel shape having a predetermined shape such as a rectangle.

In the present embodiment, a transparent substrate made of polyethylene terephthalate (PET) having a thickness of 200 μm is used as the second substrate 5, and the inner surface of the transparent substrate (second substrate 5) is as described above. A transparent electrode is formed as the common electrode 4. This transparent electrode (common electrode 4) is formed on the entire inner surface side of the second substrate 5, and is made of conductive oxides such as ITO (Indium Tin Oxide), and high electronic conductivity such as polyaniline. It is formed by ion conductive polymers in which ionic substances such as NaCl, LiClO ₄ , KCl are dispersed in a matrix resin such as molecules, polyvinyl alcohol resin, polycarbonate resin or the like. In the present embodiment, the transparent electrode (common electrode 4) is formed of an ITO film formed by a vapor deposition method or the like.

  Between the first substrate 3 and the second substrate 5 having such a configuration, a microcapsule 6 is disposed on the pixel electrode 2 in particular, and the microcapsule 6 is thus formed as shown in FIG. The display area 9 shown is formed. The microcapsules 6 are filled with a display material as described above, and are all formed to have substantially the same diameter. In this embodiment, the diameter is about 30 μm. The encapsulated display material has optical properties that change in response to electrical stimulation, and specifically includes electrophoretic particles and liquid crystals.

As a material mainly composed of electrophoretic particles, an electrophoretic dispersion liquid including electrophoretic particles and a liquid phase dispersion medium in which the electrophoretic particles are dispersed is used.
Examples of the liquid phase dispersion medium include water, methanol, ethanol, isopropanol, butanol, octanol, methyl cellosolve and other alcohol solvents, ethyl acetate, various esters such as butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, and other ketones. , Aliphatic hydrocarbons such as pentane, hexane and octane, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, benzene, toluene, xylene, hexylbenzene, hebutylbenzene, octylbenzene, nonylbenzene, decyl Aromatic hydrocarbons such as benzenes having a long chain alkyl group such as benzene, undecylbenzene, dodecylbenzene, tridecylbenzene, tetradecylbenzene, etc., halo such as methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, etc. Emissions of hydrocarbons, can be used by blending a surfactant or the like to the carboxylate or other various oils, etc. alone or a mixture thereof.

The electrophoretic particles are organic or inorganic particles (polymer or colloid) having a property of moving by electrophoresis due to a potential difference in a liquid phase dispersion medium.
Examples of the electrophoretic particles include black pigments such as aniline black, carbon black, and titanium black, white pigments such as titanium dioxide, zinc white, and antimony trioxide, azo pigments such as monoazo, diisazone, and polyazo, and isoindolinone. Yellow pigments such as yellow lead, yellow iron oxide, cadmium yellow, titanium yellow, antimony, azo pigments such as monoazo, disazo, polyazo, red pigments such as quinacridone red, chrome vermilion, phthalocyanine blue, indanthrene blue, anthraquinone 1 type (s) or 2 or more types, such as a system pigment, blue pigments, such as bitumen, ultramarine blue, and cobalt blue, and green pigments, such as phthalocyanine green, can be used.

Furthermore, these pigments include, as necessary, charge control agents composed of particles of electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, compounds, titanium-based coupling agents, aluminum-based coupling agents. A dispersant such as a silane coupling agent, a lubricant, a stabilizer, and the like can be added.
As a material for forming the wall film of the microcapsule 6, a compound such as a composite film of gum arabic / gelatin, urethane resin, urea resin, urea resin can be used.

In the display device 1 of the present example, two types of electrophoretic particles are enclosed in the microcapsule 6, one being negatively charged and the other being positively charged. As these two types of electrophoretic particles, for example, titanium dioxide that is a white pigment and carbon black that is a black pigment are used. Then, by using such two types of electrophoretic particles of white and black, for example, when displaying numbers or the like, it is possible to display the numbers or the like with black electrophoretic particles.
Alternatively, display may be performed by using only one type of electrophoretic particle and moving it to the common electrode 4 side or the pixel electrode 2 side.

  The microcapsules 6 are fixed to the second substrate 5 by the binder 10 on the common electrode 4. As the binder 10, those having good affinity for the wall film of the microcapsule 6, excellent adhesion to the common electrode 4, and insulating properties can be used. For example, polyethylene, chlorinated polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polypropylene, ABS resin, methyl methacrylate resin, vinyl chloride resin, vinyl chloride-vinyl acetate copolymer, vinyl chloride -Vinylidene chloride copolymer, vinyl chloride acrylate copolymer, vinyl chloride-methacrylic acid copolymer, vinyl chloride-acrylonitrile copolymer, ethylene-vinyl alcohol-vinyl chloride copolymer, propylene-vinyl chloride copolymer Polymer, thermoplastic resin such as vinylidene chloride resin, vinyl acetate resin, polyvinyl alcohol, polyvinyl formal, and cellulose resin, polyamide resin, polyacetal, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyphenyl Polymers such as oxide, polysulfone, polyamideimide, polyamino bismaleimide, polyethersulfone, polyphenylenesulfone, polyarylate, grafted polyfinylene ether, polyetheretherketone, polyetherimide, polytetrafluoroethylene, polyfluoride Fluorine resins such as ethylene propylene, tetrafluoroethylene-perfluoroalkoxyethylene copolymer, ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, polytrifluoroethylene chloride, fluororubber, silicone resin, silicone rubber As other silicon resins, methacrylic acid-styrene copolymer, polybutylene, methyl methacrylate-butadiene-styrene copolymer, and the like can be used.

On the other hand, these microcapsules 6 are fixed to the first substrate 3 by the double-sided adhesive sheet 11 on the pixel electrode 2. The double-sided adhesive sheet 11 has a rubber or acrylic adhesive having a thickness of about 25 μm, is fixed on the pixel electrode 2 of the first substrate 3, and is attached to the microcapsule 6. The microcapsule 6 is held and fixed on the first substrate 3 by being fixed.
With such a configuration, the microcapsule 6 is sandwiched between the first substrate 3 and the second substrate 5 to form a display region 9.

  A substrate electrode 7 is disposed outside the display area 9 as shown in FIG. 2, and a conductive material 8 is disposed on the substrate electrode 7 as shown in FIG. This conductive material 8 constitutes, together with the substrate electrode 7, a vertical conduction portion 12 that conducts between the first substrate 3 and the second substrate 5, and contains conductive particles in the resin. It is. That is, the conductive material 8 is made of conductive particles such as metal particles such as silver or nickel particles formed by crushing, carbon particles, and nickel-plated cores made of resin, and gold-plated particles. It consists of a conductive paste blended and contained in a resin, etc., or a conductive sheet obtained by processing this conductive paste into a sheet. In particular, regarding the resin, the same rubber-based or acrylic-based one as the double-sided adhesive sheet 11 is preferably used as the one having adhesiveness at room temperature.

  Here, regarding the thickness of the conductive material 8 that constitutes the vertical conduction part 12 together with the substrate electrode 7 in this way, the interval W1 between the first substrate 3 and the second substrate 5 in the vertical conduction part 12 is set as follows. The thickness of the display area 9 is larger than the distance W2 between the first substrate 3 and the second substrate 5. That is, the interval W1 between the first substrate 3 and the second substrate 5 in the vertical conduction part 12 is substantially the sum of the thicknesses of the substrate electrode 7, the conductive material 8, and the common electrode 4. The distance W2 between the first substrate 3 and the second substrate 5 in the display area 9 is substantially equal to the thickness composed of the pixel electrode 2 and the double-sided adhesive sheet 11, the microcapsule 6 and the binder 10. And the total thickness of the common electrode 4. Therefore, by making the thickness of the conductive material 8 larger than the sum of the diameter of the microcapsule 6 and the thickness of the double-sided adhesive sheet 11, the W1 can be made wider than W2.

  Thus, by making the interval W1 between the substrates in the vertical conduction part 12 larger than the interval W2 between the substrates in the display region 9, the first substrate 3 having a particularly small substrate thickness as shown in FIG. The vertical conducting portion 12 side, that is, the outside is elastically deformed (warped) outward as indicated by an arrow A in FIG. Then, the first substrate 3 exerts a force acting on the inner side as indicated by an arrow B in FIG.

  Here, with respect to the width of W1 with respect to W2, that is, the difference between W1 and W2, W1 is preferably wider than W2 in the range of 10 μm to 200 μm, particularly 50 μm to 80 μm. It is more preferable that the width becomes wider. If the width W1 between the substrates in the vertical conduction part 12 is less than 10 μm, the pressing force to the conductive material 8 side by the elastic restoring force becomes low, and peeling may occur in the above-described reliability test. If the thickness exceeds 200 μm, the microcapsules 6 located in the vicinity of the upper and lower conductive portions 12 may be peeled off from the substrate 3 (5) due to a change over time over a long period of time, which may cause a display defect. Therefore, as described above, by setting and forming the thickness of the conductive material 8 so that the width of W1 with respect to W2 is in the range of 10 μm or more and 200 μm or less, long-term reliability related to conduction failure and long-term related to display failure. Reliability can be ensured together. In particular, the long-term reliability can be ensured more favorably by setting it in the range of 50 μm to 80 μm.

  It should be noted that there are a plurality of upper and lower conductive portions 12 and, therefore, it is considered that there is a variation in the interval W1 between the substrates in the upper and lower conductive portions 12. In this case, the average value of the plurality of W1 is set as the upper and lower conductive portions in the present invention. The interval W1 between the substrates in the portion 12 is set. Further, as shown in FIG. 1, there is also a variation in the interval W2 between the substrates in the display region 9, but for this W2, the minimum value in the plurality of W2 is set to the interval between the substrates in the display region 9 in the present invention. Let W2.

Here, the conductive material 8 constituting the upper and lower conductive portions 12 is not formed on the entire surface of the substrate electrode 7 as shown in FIG. 2 but is disposed on a part of the upper surface of the substrate electrode 7. . Therefore, the portion where the substrate electrode 7 and the conductive material 8 are laminated is the vertical conductive portion 12 in the present invention. An adhesive layer 13 is formed on and near the substrate electrode 7 where the conductive material 8 is not disposed.
As described above, the adhesive layer 13 is provided at a position different from the display region 9 as well as the vertical conduction portion 12. The adhesive layer 13 is provided between the first substrate 3 and the second substrate 5 (common electrode 4 thereof). By being disposed in between, the first substrate 3 and the second substrate 5 are fixed, and the substrates are more firmly bonded.

In particular, when the adhesive layer 13 is made of a resin having a stronger adhesive force than the conductive material 8, the adhesive layer 13 is provided on the substrate electrode 7 to reinforce the adhesion between the substrate electrode 7 and the conductive material 8. In addition, peeling between them is prevented.
Further, when the adhesive layer 13 is made of a moisture-proof resin, the vertical conductive portion 12 and the display region 9 are surrounded outside the vertical conductive portion 12 and the display region 9 particularly near the substrate electrode 7. By being disposed in a wet state, moisture permeability is suppressed, and electrode corrosion, microcapsule deterioration, and the like due to moisture (moisture) in the atmosphere are prevented. Here, as the moisture-proof resin, a resin having a high crosslinking density such as an epoxy resin is used.

  In FIG. 2, the conductive material 8 is arranged at one place on the substrate electrode 7 and a single upper and lower conductive portion 12 is formed on one substrate electrode 7. However, as shown in FIG. The conductive material 8 may be arranged at a plurality of (for example, three) locations on the substrate 7, and the plurality of upper and lower conductive portions 12 may be formed on one substrate electrode 7. In that case, by forming the adhesive layer 13 between the plurality of conductive materials 8, as described above, the adhesion between the substrate electrode 7 and the conductive material 8 is reinforced, and peeling between them is prevented. Can do.

In order to manufacture the display device 1 having such a configuration, first, as shown in FIG. 4A, a first substrate 3 made of an elastically deformable polyimide having a thickness of about 25 μm is prepared, and a substrate electrode is prepared thereon. 7. The pixel electrode 2 is formed by a known method such as the semi-additive method described above.
Next, as shown in FIG. 4B, the conductive sheet as the conductive material 8 is arranged at a predetermined position on the substrate electrode 7 and fixed thereto. Here, as described above, the thickness of the conductive sheet serving as the conductive material 8 is set to a predetermined thickness so that W1 in FIG. 1 is wider than W2.

Separately, a transparent substrate made of polyethylene terephthalate (PET) is prepared as the second substrate 5, and a transparent electrode (common electrode 4) made of ITO is deposited on one surface (inner surface) of this by vapor deposition or the like. Formed by.
A large number of microcapsules 6 are fixed using a binder 10 at a predetermined position on the common electrode 4 of the second substrate 5, that is, a position corresponding to the display area 9.
Next, a double-sided adhesive sheet 11 is attached to the side of the microcapsules 6 opposite to the second substrate 5 side.

  Next, the second substrate 5 to which the double-sided adhesive sheet 11 is adhered in this manner is placed on the first substrate 3 and is opposed to the first substrate 3. Then, as shown in FIG. 4C, the double-sided adhesive sheet 11 of the second substrate 5 is pressed against the side of the first substrate 3 where the pixel electrode 2 is formed, and the double-sided adhesive sheet 11 is adhered. Then, the common electrode 4 of the second substrate 5 is pressed against the conductive material 8 on the first substrate 3 and is fixed therebetween. As a result, the first substrate 3 and the second substrate 5 are integrated via the conductive material 8, the double-sided adhesive sheet 11, etc., and the microcapsules are interposed between the first substrate 3 and the second substrate 5. 6 is pinched. Here, the sticking of the double-sided adhesive sheet 11 and the fixing with the conductive material 8 are basically performed at room temperature without heating, and within a range that does not adversely affect the microcapsules 6 as necessary. It shall be performed with heating.

  When the first substrate 3 and the second substrate 5 are integrated in this way, the interval W1 between the first substrate 3 and the second substrate 5 in the upper and lower conductive portions 12 is set to be the first in the display region 9. As a result, the outer peripheral portion of the first substrate 3 is elastically deformed outward (warped) as shown in FIG. 4C. The distance W2 between the first substrate 3 and the second substrate 5 is larger. The elastic restoring force works in the direction opposite to the elastically deformed direction.

  Next, an adhesive is injected between the first substrate 3 and the second substrate 5 from the outer peripheral side by a dispenser or the like, and a portion where the conductive material 8 is not disposed on the substrate electrode 7 and its vicinity. That is, as shown in FIG. 4D, an adhesive is disposed at a position surrounding the upper and lower conductive portions 12 and the display area 9. Thereafter, this is cured to form the adhesive layer 13 to obtain the display device 1. As the adhesive, an adhesive that cures without heating, such as an ultraviolet irradiation curing type, is used. However, it is also possible to use a material that cures by heating within a range that does not adversely affect the microcapsules 6, as in the case of the above-described sticking process of the double-sided adhesive sheet 11.

  In the display device 1 obtained in this way, the thickness of the conductive material 8 is set so that the interval W1 between the substrates in the vertical conductive portion 12 is wider than the interval between the substrates in the display region 9. Since the vertical conduction part 12 is formed, as described above, the first substrate 3 presses the conductive material 8 side as shown by an arrow B in FIG. Demonstrate power. Therefore, since the first substrate 3 always presses the conductive material 8 side in this way, the first substrate 3 and the second substrate 3 can be used even when a reliability test such as standing at a high temperature or a temperature cycle is performed. Peeling between the substrate 5 and the conductive material 8 is prevented, thereby ensuring long-term reliability as a product.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, when the double-sided adhesive sheet 11 is adhered to the side opposite to the second substrate 5 side of the microcapsule 6 fixed to the second substrate 5 in the manufacturing process of the display device 1, the double-sided adhesive sheet 11. Alternatively, a material having a thickness of 25 μm or more may be used. When the double-sided adhesive sheet 11 having such a thickness is used and pressed against the side of the first substrate 3 on which the pixel electrode 2 is formed, the double-sided adhesive sheet 11 is adhered and fixed, for example, 50 The double-sided adhesive sheet 11 is softened by heating at a temperature equal to or higher than 0 ° C. (however, a temperature that does not adversely affect the microcapsules 6), and a part of the double-sided adhesive sheet 11 protrudes to the vertical conduction part 12 side. Subsequently, by curing in that state, a portion protruding between the microcapsule 6 and the vertical conduction portion 12 as shown in FIG.

  Thereafter, as in the case shown in FIG. 4D, an adhesive is injected between the first substrate 3 and the second substrate 5 from the outer peripheral side by a dispenser or the like, and is further cured. Thereby, the adhesive layer 13 is formed, and a display device is obtained.

In such a display device, the same effect as in the case of the display device 1 can be obtained, and the first substrate 3 and the second substrate 5 are more firmly bonded. Further, since the bonding in the vicinity of the vertical conduction part 12 becomes strong, the peeling of the vertical conduction part 12 with respect to the first substrate 3 or the second substrate 5 is surely prevented.
In addition, since the formation of the adhesive layer 14 is performed simultaneously with the step of sandwiching the microcapsule between the first substrate 3 and the second substrate 5 by using the double-sided adhesive sheet 11, a new step is performed. The adhesive layer 14 can be formed without the addition, thereby facilitating the manufacturing process.

In the embodiment, the first substrate 3 on which the pixel electrode 2 is formed is elastically deformed outward by making the first substrate 3 thinner than the second substrate 5 on which the common electrode 4 is formed. Although the elastic restoring force that presses the conductive material 8 is exhibited, the second substrate 5 side may be elastically restored, and the first substrate 3 and the second substrate 5 are equivalent. By making this strength, both the substrates may be elastically deformed together, and each may exhibit an elastic restoring force.
In the above-described embodiment, the case where there is one display region has been described. However, the present invention can also be applied to a case where a plurality of display regions are independently formed in an island shape.

Next, the electronic apparatus of the present invention will be described. An electronic apparatus according to the present invention includes the above-described display device according to the present invention.
Hereinafter, an example of an electronic apparatus including the display device will be described.

<Mobile computer>
First, an example in which the display device is applied to a mobile personal computer will be described. FIG. 6 is a perspective view showing the configuration of this personal computer. As shown in FIG. 6, the personal computer 80 includes a main body 82 including a keyboard 81 and a display unit including the display device 64.

<Mobile phone>
Next, an example in which the display device is applied to a display unit of a mobile phone will be described. FIG. 7 is a perspective view showing the configuration of this mobile phone. As shown in FIG. 7, the cellular phone 90 includes the display device 64 together with a plurality of operation buttons 91, an earpiece 92 and a mouthpiece 93.

<Electronic paper>
Next, the example which applied the said display apparatus to the display part of electronic paper is demonstrated. FIG. 8 is a perspective view showing the configuration of the electronic paper. The electronic paper 110 includes a main body 111 made of a rewritable sheet having the same texture and flexibility as paper, and a display unit including the display device 64.

<Electronic notebook>
FIG. 9 is a perspective view showing the configuration of the electronic notebook. As shown in FIG. 9, the electronic notebook 120 is a bundle of a plurality of electronic papers 110 shown in FIG. 8, and these electronic papers 110 are sandwiched between covers 121. By providing the display data input means on the cover 121, the display content of the electronic paper can be changed in a bundled state.

According to such an electronic device, since the display device with long-term reliability secured is provided as described above, each of the electronic devices themselves is also secured with long-term reliability.
In addition to the personal computer shown in FIG. 6, the mobile phone shown in FIG. 7, the electronic paper shown in FIG. 8, and the electronic notebook shown in FIG. IC card equipped with the above, and further, electronic book, viewfinder type, monitor direct-view type video tape recorder, car navigation device, pager, electronic notebook, calculator, word processor, workstation, videophone, POS terminal, touch panel Examples of such devices are provided. And it cannot be overemphasized that the said display apparatus is applicable as a display part of these various electronic devices.

  DESCRIPTION OF SYMBOLS 1 ... Display apparatus, 2 ... Pixel electrode, 3 ... 1st board | substrate, 4 ... Common electrode, 5 ... 2nd board | substrate, 6 ... Microcapsule, 7 ... Substrate electrode, 8 ... Conductive material, 9 ... Display area, 10 DESCRIPTION OF SYMBOLS ... Binder, 11 ... Double-sided adhesive sheet, 12 ... Vertical conduction part, 13 ... Adhesive layer, 14 ... Adhesive layer, W1 ... Space | interval between the 1st board | substrate and 2nd board | substrate in a vertical conduction part, W2 ... Display area The distance between the first substrate and the second substrate in

Claims (10)

A first substrate; a second substrate; and a microcapsule that is sandwiched between the first substrate and the second substrate to form a display region. Correspondingly, a display material whose optical characteristics change is enclosed,
Between the first substrate and the second substrate, a conductive material for conducting between these substrates is provided to form a vertical conduction portion,
The conductive material has a thickness that makes the interval between the first substrate and the second substrate in the vertical conduction part wider than the interval between the first substrate and the second substrate in the display region. A display device characterized by being provided.   The conductive material has an interval between the first substrate and the second substrate in the vertical conductive portion that is 10 μm or more and 200 μm from an interval between the first substrate and the second substrate in the display region. A display device characterized by being provided with a thickness that is widened in the following range.   The display device according to claim 1, wherein the vertical conduction portion is disposed on an outer peripheral portion of the first substrate and the second substrate.   An adhesive layer for fixing the first substrate and the second substrate is provided between the first substrate and the second substrate at a position different from the vertical conduction portion and the display region. The display device according to claim 1, wherein the display device is a display device.   A substrate electrode is formed on one of the first substrate and the second substrate at a position including the vertical conduction portion, and the adhesive layer is provided on the substrate electrode other than the vertical conduction portion. The display device according to claim 4, wherein   The display device according to claim 4, wherein the adhesive layer is provided between the microcapsule and the vertical conduction portion. The microcapsule is bonded to the first substrate or the second substrate,
The display device according to claim 6, wherein the adhesive of the adhesive layer is the same as the adhesive that adheres the microcapsules to the first substrate or the second substrate. The microcapsule is bonded to the first substrate or the second substrate with an adhesive sheet having a thickness of 25 μm or more,
The display device according to claim 7, wherein the adhesive of the adhesive layer is formed by protruding a part of the adhesive sheet to the vertical conduction part side.   5. The display according to claim 4, wherein the adhesive layer is made of a moisture-proof resin, and is disposed outside the vertical conduction part and the display area so as to surround the vertical conduction part and the display area. apparatus.   An electronic apparatus comprising the display device according to claim 1.

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