JP2010181463A - Method of manufacturing electrophoretic display device, electrophoretic display device, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an electrophoretic display device having high moisture preventing properties and high reliability, the electrophoretic display device and an electronic device. <P>SOLUTION: The method of manufacturing the electrophoretic display device includes a step of sticking an electrophoretic sheet 3 having an electrophoretic layer 31 and an adhesion layer 33 provided on a transparent substrate 30 to a display area of an element substrate 2 via the adhesion layer, a step of sticking moisture preventing film sides of surface members formed by sticking moisture preventing film 53 and 62 to protection members 51 and 61 having rigidity higher than that of the moisture preventing films to at least one of surfaces of the transparent substrate 30 and the element substrate 2 and a step of forming a sealing material so as to cover an exposure part of an peripheral edge of the electrophoretic layer and come in contact with the transparent substrate 30, the element substrate 2 and the moisture preventing films 53 and 62. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  An electrophoretic display device has come to be used as a display unit for electronic paper or a clock face. The electrophoretic display device has an electrophoretic layer containing an electrophoretic dispersion liquid in which a plurality of electrophoretic particles are dispersed in a liquid phase dispersion medium, and an electric field is applied to the electrophoretic layer, thereby This is a device that utilizes the fact that the optical properties of the electrophoretic dispersion change as the distribution state changes. As a specific configuration of the electrophoretic display device, an electrophoretic sheet is attached to a display region of an element substrate on which a plurality of pixel electrodes and elements are formed, and a protective substrate is attached to the electrophoretic sheet. Are known.

  The electrophoretic sheet has a configuration in which an electrophoretic layer and an adhesive layer are formed on a transparent sheet on which a transparent electrode such as ITO is deposited. As the electrophoretic layer, for example, a configuration in which a plurality of microcapsules in which an electrophoretic dispersion liquid containing electrophoretic particles is enclosed is spread on one surface of the sheet can be given.

  The electrophoretic display device having a microcapsule has a problem in that the display characteristics are adversely affected if too much or too little moisture is held in the microcapsule. In addition, when the sealing structure of the electrophoretic layer is insufficient, there is a problem in that display characteristics are likely to be deteriorated due to a change in temperature and humidity in an environment where the electrophoretic display device is used.

  For this reason, establishment of a highly moisture-proof sealing structure that minimizes the entry and exit of moisture from the periphery of the electrophoretic display device has been demanded. For example, as described in Patent Document 1, by attaching a moisture-proof film so that an excess portion is provided at the end of the substrate constituting the electrophoretic display device, and providing a moisture-proof resin between the moisture-proof films A method for ensuring moisture resistance has been proposed.

JP 2007-72128 A

  However, in the configuration of Patent Document 1, when a soft moisture-proof film is attached, a gap is easily formed at the interface between the moisture-proof film and the moisture-proof resin due to the twist of the moisture-proof film, and the sealing performance becomes insufficient. There was a problem that it was easy. For this reason, there was a possibility that sufficient moisture resistance could not be obtained and the configuration would be easily affected by environmental changes.

  In view of the circumstances as described above, an object of the present invention is to provide an electrophoretic display device manufacturing method, an electrophoretic display device, and an electronic apparatus that are highly moisture-proof and highly reliable.

  The method for manufacturing an electrophoretic display device according to the present invention includes a step of bonding an electrophoretic sheet, in which an electrophoretic layer and an adhesive layer are provided on a transparent substrate, to the display region of an element substrate via the adhesive layer, A step of attaching the moisture-proof film side of the surface member on which the film is bonded to a protective member having higher rigidity than the moisture-proof film to at least one of the surface of the transparent substrate and the surface of the element substrate; and the electrophoretic layer And a step of forming a sealing material so as to cover the exposed portion at the peripheral edge of the transparent substrate, and to be in contact with the transparent substrate, the element substrate, and the moisture-proof film.

  According to the present invention, the surface member in a state where the moisture-proof film is bonded to the protective member having higher rigidity than the moisture-proof film is attached to at least one of the surface of the transparent substrate and the surface of the element substrate. It is possible to prevent a gap from being generated due to the twist of the moisture-proof film in the region in contact with the stopper, and the adhesion can be improved. Thereby, an electrophoretic display device having high moisture resistance and high reliability can be manufactured. In addition, since the surface member in a state where the moisture-proof film and the protective member are bonded together is used, the number of steps can be reduced as compared with the case where the moisture-proof film and the protective member are bonded individually. Thereby, an electrophoretic display device can be manufactured efficiently.

The manufacturing method of the electrophoretic display device is characterized in that, in the step of attaching the surface member, the surface member is attached to the surface of the transparent substrate.
According to the present invention, in the step of attaching the surface member, since the surface member is attached to the surface of the transparent substrate, moisture resistance on the transparent substrate side can be reliably improved.

The method for manufacturing an electrophoretic display device is characterized in that, in the step of attaching the surface member, the surface member is attached to the surface of the element substrate.
According to the present invention, in the step of attaching the surface member, since the surface member is attached to the surface of the element substrate, moisture resistance on the element substrate side can be reliably improved.

In the method for manufacturing an electrophoretic display device, the surface member is characterized in that the moisture-proof film is bonded to the protective member via an impact buffering material.
According to the present invention, since the shock absorbing material is provided between the moisture-proof film and the protective member, an electrophoretic display device having high impact resistance can be manufactured.

  An electrophoretic display device according to the present invention includes an electrophoretic display panel in which an electrophoretic sheet provided with an electrophoretic layer and an adhesive layer on a transparent substrate is bonded to the display region of an element substrate via the adhesive layer; A surface in which the moisture-proof film and a protective member having higher rigidity than the moisture-proof film are bonded together, and the moisture-proof film side of the surface member is bonded to at least one of the surface of the transparent substrate and the surface of the element substrate It comprises a member and a sealing material provided so as to cover the exposed portion at the peripheral edge of the electrophoretic layer and to be in contact with the transparent substrate, the element substrate, and the moisture-proof film.

  According to the present invention, in the region in contact with the sealing material, there is no gap due to twisting of the moisture-proof film, and a structure with high adhesion can be obtained. Thereby, an electrophoretic display device having high moisture resistance and high reliability can be obtained.

An electronic apparatus according to the present invention includes an electrophoretic display device.
According to the present invention, since an electrophoretic display device having high moisture resistance and high reliability is mounted, an electronic apparatus having a long life and high display quality can be obtained.

1 is a plan view showing a configuration of an electrophoretic display device according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view showing the configuration of the electrophoretic display device according to the embodiment. FIG. 5 is a process diagram illustrating a manufacturing process of an electrophoretic display device. The process drawing. The process drawing. The process drawing. The process drawing. The figure which shows the structure of the electronic device which concerns on 2nd Embodiment of this invention.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing a schematic configuration of an electrophoretic display device 1 according to the present embodiment. FIG. 2 is a diagram showing a configuration along the section AA in FIG.

  As shown in FIGS. 1 and 2, the electrophoretic display device 1 includes an electrophoretic display panel 4, surface members 8 and 9 (see FIG. 2), and a sealing material 7. The electrophoretic display panel 4 includes an element substrate 2 and an electrophoretic sheet 3. The electrophoretic display panel 4 has a configuration in which an electrophoretic sheet 3 is attached to the surface of the element substrate 2.

  As shown in FIG. 2, the surface members 8 and 9 are attached to the surface of the element substrate 2 of the electrophoretic display panel 4 and the surface of the electrophoretic sheet 3, respectively. In the present embodiment, the surface member 9 is bonded to the surface of the element substrate 2, and the surface member 8 is bonded to the surface of the electrophoretic sheet 3. The sealing material 7 is disposed between the surface member 8 and the surface member 9 so as to seal the panel side portion of the electrophoretic display panel 4. As the sealing material 7, it is preferable to use, for example, a material having rigidity and a small tack, for example, an epoxy resin or an acrylic resin. As the acrylic resin, a UV curable material, a humidity curable material, or the like can be used.

  The electrophoretic display device 1 is provided with a display area 5 for displaying images such as still images and moving images. A plurality of pixels arranged in a matrix are provided in the display area 5, and display is performed for each pixel. A region 6 around the display region 5 is a non-display region 6 where no image is displayed. The non-display area 6 is not provided with pixels, and is provided with drive circuit elements 22 and 23, a terminal 24, and the like.

  The element substrate 2 includes a substrate 20 having a thickness of about 0.5 mm, for example, and a driving layer (not shown) including pixel electrodes and elements formed on the substrate 20. Examples of the substrate 20 include inorganic substrates such as a glass substrate, a quartz substrate, a silicon substrate, and a gallium arsenide substrate, polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), and polycarbonate (PC). A plastic substrate (resin substrate) composed of polyethersulfone (PES), aromatic polyester (liquid crystal polymer), or the like can be used.

  The drive layer is formed in a region corresponding to the display region 5 in the substrate 20. In the drive layer, pixel electrodes and switching elements provided in each pixel, data lines and scanning lines connected to the switching elements, and the like (all not shown) are formed. The planar drive layer formation region substantially coincides with the display region 5, and the drive circuit elements 22 and 23 are provided in the peripheral portion (non-display region 6) of the drive layer. The drive circuit elements 22 and 23 are electrically connected to data lines and scanning lines, and supply signals to the drive layer. A plurality of terminals 24 are provided at the end of the element substrate 2 (right end in the drawing), and are connected to the drive circuit elements 22 and 23 by wiring (not shown) formed on the element substrate 2. The terminal 24 is connected to the external circuit board F.

The electrophoretic sheet 3 has a transparent substrate 30, a common electrode 35, an electrophoretic layer 31, and an adhesive layer 33.
The transparent substrate 30 has a thickness of about 0.2 mm, for example, and holds the electrophoretic layer 31, and has a high light transmittance such as polyethylene terephthalate (PET), polyethersulfone (PES), and polycarbonate (PC). A rectangular substrate made of a material. The surface 30 a side of the transparent substrate 30 is the display surface side of the electrophoretic display device 1.

  The common electrode 35 is formed almost on the entire inner surface 30 b of the transparent substrate 30. The common electrode 35 is made of a conductive material having high light transmission, such as ITO, and is connected to the element substrate 2 by the vertical conduction member 10.

The electrophoretic layer 31 has a plurality of microcapsules 32.
The microcapsule 32 is a substantially spherical capsule in which an electrophoretic dispersion is enclosed, and the diameter of each capsule is substantially the same (50 μm to 100 μm). Examples of the material for forming the capsule wall film of the microcapsule 32 include compounds such as a gum arabic / gelatin composite film, urethane resin, urea resin, and urea resin. The electrophoretic dispersion liquid enclosed in the microcapsule 32 includes a plurality of electrophoretic particles and a liquid layer dispersion medium for dispersing the electrophoretic particles.

  Examples of the liquid layer dispersion medium include water, alcohol solvents, various esters, ketones, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, carboxylates, and other various oils. These can be used alone, or a mixture of these with a surfactant or the like.

  As the electrophoretic particles, 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 can be used. Specifically, black pigments such as carbon black and aniline black, white pigments such as titanium dioxide, monoazo azo pigments, yellow pigments such as isoindolinone, monoazo azo pigments, red pigments such as quinacridone red, phthalocyanine One or more of blue pigments such as blue and green pigments such as phthalocyanine green can be used. These pigments include electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, charge control agents composed of particles such as compounds, titanium-based coupling agents, aluminum-based coupling agents, silanes as necessary. A dispersant such as a system coupling agent, a lubricant, a stabilizer, and the like can be added.

  In the microcapsule 32, for example, two types of electrophoretic particles of titanium dioxide which is a white pigment and carbon black which is a black pigment are encapsulated, one of which is negatively charged and the other of which is positively charged. Of course, other electrophoretic particles may be used, or only one type of electrophoretic particle may be used, and the electrophoretic particles may be moved to the common electrode side or the pixel electrode side so that display can be performed.

  The adhesive layer 33 is a thermosetting adhesive that also serves as a binder. The adhesive layer 33 is preferably an adhesive having good affinity for the capsule wall film of the microcapsule 32, excellent adhesion to the common electrode and the pixel electrode, and good insulation. Moreover, although it is a thermosetting type, the adhesive agent which has elasticity after hardening is preferable.

  The surface member 8 includes a protection member 51, an impact relaxation material 52, and a moisture-proof film 53. The surface member 8 has a configuration in which a moisture-proof film 53 is attached to the transparent substrate 30 of the electrophoretic sheet 3. As the protective member 51, a material having high light transmittance, excellent flatness, and higher rigidity than the moisture-proof film 53, for example, glass is suitable. Specifically, inorganic glass, crystal glass, or the like can be used. Further, sapphire glass or acrylic glass may be used. In the present embodiment, an impact relaxation material 52 is disposed between the protection member 51 and the moisture-proof film 53. By disposing the impact relaxation material 52, the impact resistance on the side of the electrophoretic sheet 3 is enhanced.

  The moisture-proof film 53 is a light transmissive soft film having a thickness of about 0.1 mm. For example, a film having an inorganic barrier layer formed on the surface of a light transmissive film such as polyethylene terephthalate or polyethylene naphthalate. Can be used. As the inorganic barrier layer, a fluorine resin excellent in moisture proofing and transparency, PCTFE (Poly Chloro Tri Furuoro Ethylene, or a trifluorinated ethylene resin) can be used. The moisture-proof film 53 is affixed to the electrophoretic sheet 3 with an adhesive layer (not shown) having a high light transmission property such as a double-sided tape or a photocurable adhesive.

  The surface member 9 has a protective member 61 and a moisture-proof film 62. The surface member 9 has a configuration in which a moisture-proof film 62 is attached to the substrate 20 of the element substrate 2. As the material of the protective member 61, for example, the same material as that of the protective member 51 can be used. As the material of the moisture-proof film 62, for example, the same material as that of the moisture-proof film 53 can be used.

Next, the operation of the electrophoretic display device 1 configured as described above will be briefly described.
When a voltage is applied between the pixel electrode 25 and the common electrode 35 so that the voltage of the common electrode 35 becomes relatively high, the positively charged black electrophoretic particles are out of the pixels in the microcapsule 32 by the Coulomb force. It is drawn toward the electrode 25 side. On the other hand, negatively charged white electrophoretic particles are attracted toward the common electrode 35 in the microcapsule 32 by Coulomb force. As a result, white electrophoretic particles gather on the transparent substrate 30 side in the microcapsule 32, and the color (white) of the white electrophoretic particles is displayed in the display area 5 of the electrophoretic display device 1. The Rukoto.

  On the contrary, when a voltage is applied between the pixel electrode 25 and the common electrode 35 so that the potential of the pixel electrode 25 becomes relatively high, the negatively charged white electrophoretic particles are moved to the pixel electrode 25 side by Coulomb force. Be drawn to. On the other hand, the positively charged black electrophoretic particles are attracted toward the common electrode 35 by the Coulomb force. As a result, black electrophoretic particles gather on the transparent substrate 30 side in the microcapsule 32, and the color (black) of the black electrophoretic particles is displayed in the display area 5 of the electrophoretic display device 1. It will be.

Next, a manufacturing process of the electrophoretic display device 1 configured as described above will be described with reference to FIGS.
First, as shown in FIG. 3, the electrophoretic sheet 3 is bonded onto the display region 5 of the element substrate 2 through the adhesive layer 33. After the electrophoretic sheet 3 is bonded, an adhesive layer (not shown) is formed on the upper surface of the electrophoretic sheet 3 as shown in FIG. 4, and the surface member 8 is bonded to the adhesive layer. When the surface member 8 is bonded, the surface member 8 is aligned so that it protrudes from the four sides of the element substrate 2 in plan view, and the moisture-proof film 53 side is bonded to the electrophoretic sheet 3 after alignment. Like that.

  After the surface member 8 is attached, the surface member 9 is attached to the surface of the element substrate 2 via an adhesive layer (not shown) as shown in FIG. When the surface member 8 is bonded, the surface member 9 is aligned so that it protrudes from the four sides of the element substrate 2 in plan view, and the moisture-proof film 62 side is bonded to the element substrate 2 after alignment. To.

  Through the above steps, the surface member 8 and the surface member 9 are attached to the electrophoretic display panel 4 so as to protrude from the four sides of the element substrate 2 in plan view. In this state, as shown in FIG. 6, the sealing material 7 is disposed between the surface member 8 and the surface member 9 without a gap. The sealing material 7 is disposed so as to close the exposed portion of the peripheral edge of the electrophoretic layer 31. By this step, the sealing material 7 seals the side surface of the transparent substrate 30 and the side surface of the element substrate 2. After the sealing material 7 is disposed, the sealing material 7 is cured.

  In a state where the sealing material 7 is cured, as shown in FIG. 6, a part (outer periphery) of the surface member 8 and a part (outer periphery) of the surface member 9 are in a state of protruding from the sealing material 7. . In this state, as shown in FIG. 7, portions of the surface member 8 and the surface member 9 that protrude from the sealing material 7 are cut and removed. In this way, the electrophoretic display device 1 is manufactured.

  As described above, according to this embodiment, the surface members 8 and 9 in a state where the moisture-proof films 53 and 62 are bonded to the protective members 51 and 61 having higher rigidity than the moisture-proof films 53 and 62 are formed on the element substrate 2. Since it is attached to the surface and the surface of the transparent substrate 30, it is possible to prevent a gap from being generated due to the twist of the moisture-proof films 53 and 62 in the region in contact with the sealing material 7, and to improve the adhesion. it can. Thereby, the electrophoretic display device 1 having high moisture resistance and high reliability can be manufactured.

  In addition, since the surface members 8 and 9 in a state where the moisture-proof films 53 and 62 and the protection members 51 and 61 are bonded together are used, the moisture-proof films 53 and 62 and the protection members 51 and 61 are bonded individually. Compared to the case, the number of steps can be shortened. Thereby, the electrophoretic display device 1 can be efficiently manufactured.

  In the present embodiment, since the surface members 8 and 9 are attached to both surfaces of the electrophoretic display panel 4, it is possible to ensure moisture resistance and impact resistance on both surfaces of the electrophoretic display panel 4. it can. In addition, since the shock absorbing material 52 is disposed between the protective member 51 and the moisture-proof film 53 on the surface member 8, it is possible to obtain a further impact resistance on the surface member 8 side. Moreover, in this embodiment, since the sealing material 7 is also arranged on the side surface of the element substrate 2, it is possible to make it difficult for moisture to enter from the element substrate 2 side.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the present embodiment, a case where the electrophoretic display device 100 of the above embodiment is applied to an electronic device will be described.

  FIG. 8A is a perspective view illustrating a configuration of the electronic paper 1100. An electronic paper 1100 includes the electrophoretic display device 1 of the above embodiment in a display area 1101. The electronic paper 1100 is flexible and includes a main body 1102 made of a rewritable sheet having the same texture and flexibility as conventional paper.

  FIG. 8B is a perspective view showing the configuration of the electronic notebook 1200. An electronic notebook 1200 is obtained by bundling a plurality of the electronic papers 1100 and sandwiching them between covers 1201. The cover 1201 includes display data input means (not shown) for inputting display data sent from an external device, for example. Thereby, according to the display data, the display content can be changed or updated while the electronic paper is bundled.

  According to the electronic paper 1100 and the electronic notebook 1200 described above, since the electrophoretic display device 1 according to the present invention is employed, the electronic device includes a display unit that has a long life and excellent display quality.

  In addition, said electronic device illustrates the electronic device which concerns on this invention, Comprising: The technical scope of this invention is not limited. For example, the electrophoretic display device according to the present invention can also be suitably used for display units of other electronic devices such as mobile phones and portable audio devices.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the surface member is attached to both surfaces (the surface of the electrophoretic sheet 3 and the surface of the element substrate 2) of the electrophoretic display panel 4, but the present invention is not limited to this. A configuration may be adopted in which a surface member is attached to one surface of the electrophoretic display panel 4. Even in this case, sufficient moisture resistance and impact resistance can be ensured.

  Moreover, in the said embodiment, although it was set as the structure which arrange | positions the impact relaxation material 52 only to the surface member 8, it is not restricted to this, For example, it is good also as a structure which arrange | positions an impact relaxation material also to the surface member 9. . In this case, the impact relaxation material can be disposed between the protection member 61 and the moisture-proof film 62. Thereby, impact resistance can be ensured also on the surface member 9 side.

    DESCRIPTION OF SYMBOLS 1 ... Electrophoretic display device 2 ... Element board | substrate 3 ... Electrophoretic sheet 4 ... Electrophoretic display panel 5 ... Display area 7 ... Sealing material 8, 9 ... Surface member 31 ... Electrophoretic layer 51, 61 ... Protection member 52 ... Impact Relief material 53, 62 ... Moisture-proof film 1100 ... Electronic paper 1200 ... Electronic notebook

Claims (6)

Bonding the electrophoretic sheet provided with the electrophoretic layer and the adhesive layer on the transparent substrate onto the display region of the element substrate via the adhesive layer;
A step of attaching the moisture-proof film side of the surface member bonded to the protective member having a higher moisture-resistance film than the moisture-proof film to at least one of the surface of the transparent substrate and the surface of the element substrate;
A method of manufacturing an electrophoretic display device, comprising: a step of covering an exposed portion of a peripheral portion of the electrophoretic layer and forming a sealing material so as to be in contact with the transparent substrate, the element substrate, and the moisture-proof film. . The method for manufacturing an electrophoretic display device according to claim 1, wherein in the step of attaching the surface member, the surface member is attached to a surface of the transparent substrate. The method for manufacturing an electrophoretic display device according to claim 1, wherein in the step of attaching the surface member, the surface member is attached to a surface of the element substrate. The electrophoretic display device manufacturing method according to any one of claims 1 to 3, wherein the moistureproof film is bonded to the protective member via an impact buffering material. Method. An electrophoretic display panel in which an electrophoretic sheet provided with an electrophoretic layer and an adhesive layer on a transparent substrate is bonded to the display region of the element substrate via the adhesive layer;
A surface in which the moisture-proof film and a protective member having higher rigidity than the moisture-proof film are bonded together, and the moisture-proof film side of the surface member is bonded to at least one of the surface of the transparent substrate and the surface of the element substrate Members,
An electrophoretic display device comprising: a sealing material provided to cover an exposed portion of a peripheral edge of the electrophoretic layer and to be in contact with the transparent substrate, the element substrate, and the moisture-proof film.   An electronic apparatus comprising the electrophoretic display device according to claim 5.

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