JP2014089421A - Reflection type display device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflection type display device capable of preventing a moisture content or oxygen from entering inside a cell located at a position corresponding to a display part of a display device, and a manufacturing method of the reflection type display device.SOLUTION: A reflection type display device encapsulates a display medium including at least one kind of electricity-responsive material between two opposing substrates. At least one of the two substrates is transparent, and an electrode is formed in each of the two substrates. The display medium displays predetermined information when a predetermined electric field is applied between the two substrates. A partition wall is formed in a predetermined first pattern in a first area used for a predetermined display on one substrate, and in a predetermined second pattern in a second area around the first area. A sealing member for sealing a space is arranged above the first area between the one substrate and the other substrate so as to surround the first area. The partition wall of the first pattern and the partition wall of the second pattern are indirectly connected with each other.

Description

  The present invention relates to a reflective display device applied to electronic paper or the like and a method for manufacturing the same.

  Recently, as a reflective display device, an electrophoretic display device using an electrophoretic material as an electroresponsive material contained in a display medium has been widely used. An electrophoretic display device is a device that displays information by using electrophoretic migration, that is, particle movement, of an electrophoretic body (usually electrophoretic particles) in air or in a solvent. In general, an electrophoretic state is controlled by applying an electric field between two substrates, thereby realizing a desired display. As the electrophoretic body, charged powder as well as charged particles can be used. In that case, the charged powder electrophoreses in the gas.

  In recent years, the electrophoretic display device has attracted attention especially as an electronic paper. When applied as an electronic paper, it is possible to enjoy advantages such as visibility at the printed matter level (easy for eyes), ease of information rewriting, low power consumption, and light weight.

  However, in an electrophoretic display device, display defects, particularly a decrease in contrast, may occur due to sedimentation or uneven distribution of particles or powder. In order to prevent this phenomenon, it is used to form partition walls between the upper and lower electrode substrates and divide the migration space of the particles and powder to be electrophoresed, that is, the movement space into minute spaces. This minute space is called a cell. In each cell, ink or gas (display medium) containing an electrophoretic body is enclosed.

  For example, Patent Document 1 (Japanese Patent Laid-Open No. 2003-345260) and Patent Document 2 (Japanese Patent Laid-Open No. 2007-163660) disclose conventional examples of electrophoretic display devices using a gas containing an electrophoretic material as a display medium. Has been.

  Patent Document 3 (Japanese Patent No. 4642014) discloses a method for manufacturing a sheet for manufacturing an electrophoretic display device having a cell for enclosing a display medium.

JP 2003-345260 A JP 2007-163660 A Japanese Patent No. 4642014

  By the way, although the change in the properties of the display medium sealed in the cell and the generation of bubbles in the cell lead to the deterioration of the display quality of the reflective display device, the present inventor repeatedly researches this problem. Among them, the following findings were obtained.

  When moisture, oxygen, or the like enters the cell located in the area corresponding to the display unit of the display device from the outside of the area, the properties of the display medium in the cell change or bubbles are generated in the cell. Resulting in. Therefore, if a sealing member is arranged so as to surround the region corresponding to the display unit and the region corresponding to the display unit is sealed together with the upper and lower electrode substrates, the cell is in the region corresponding to the display unit. It is considered that moisture, oxygen, and the like can be prevented from entering from the outside of the region corresponding to the display portion.

  However, even if the sealing agent having excellent sealing performance around the area corresponding to the display unit is used as a sealing member to seal the area corresponding to the display unit, the partition of the area corresponding to the display unit and the partition When the external partition wall is continuous, the sealing agent cannot intervene in the continuous part, so that the sealing performance by the sealing agent is not fully exhibited. For example, it corresponds to the display part through the continuous part of the partition wall. Moisture, oxygen, or the like may enter the cell located in the region.

  The present invention has been made based on such circumstances, and its purpose is a reflection type in which moisture, oxygen, and the like are prevented from entering a cell located in a region corresponding to the display unit of the display device. The object is to provide a display device and a method of manufacturing a reflective display device.

  In the present invention, a display medium containing at least one or more kinds of electrically responsive materials is sealed between two opposing substrates, at least one of which is transparent and on which an electrode is formed, between the two substrates. A reflective display device in which the display medium performs a predetermined display when a predetermined electric field is applied thereto, and includes a display area used for the predetermined display of the one substrate on one substrate. Or at least a part of the first area included in the display area of the one substrate and the area around the first area and not used for the predetermined display of the one substrate. Partition walls are formed in a second pattern in the second area including the cell, and the display medium is arranged with each area partitioned by the partition walls of the first pattern in the display area of the one substrate as a cell, Said one A sealing member is provided between the plate and the other substrate so as to surround the first region and seals the space on the first region in cooperation with the one substrate and the other substrate. The first pattern barrier rib and the second pattern barrier rib are discontinuous because the sealing member is interposed between the barrier ribs and the second pattern barrier rib.

  According to the present invention, the sealing member that seals the region (first region) corresponding to the display unit of the reflective display device is provided, and the partition wall provided in the region corresponding to the display unit and the display unit The partition provided in the region (second region) corresponding to the outer peripheral portion is discontinuous because the sealing member is interposed between the two. In this case, since the sealing member cannot be interposed between the region corresponding to the display portion and the region corresponding to the outer peripheral portion thereof, the occurrence of the situation that the sealing performance by the sealing member is not fully exhibited is suppressed. It is also suppressed that moisture, oxygen or the like enters from the outside into the cell located in the region corresponding to the display portion through the partition wall where the member cannot intervene.

  Preferably, the second pattern is a discontinuous pattern. In this case, for example, when the partition walls are formed by a photolithography method or the like, the developer easily enters between the partition walls, and the partition walls of the second pattern are easily formed. In addition, it is not necessary to design the second pattern partition so as to form a space (cell) surrounded by continuous partition walls, that is, to ensure that the developer enters the region where the space is formed. The width of the second pattern partition can be increased with respect to the interval between the second pattern partitions. As a result, the strength of the partition walls of the second pattern can be increased.

  Alternatively, in the present invention, a display medium containing at least one kind of electrically responsive material is sealed between two opposing substrates, at least one of which is transparent and on which an electrode is formed, A method of manufacturing a reflective display device in which a predetermined display is performed by a display medium when a predetermined electric field is applied between substrates, and used for a predetermined display on the one substrate on one substrate A first pattern included in the display area of the one substrate, and a predetermined display on the one substrate around the first area. A partition forming step of forming a partition with a second pattern in a second region including at least a part of a region that is not used, and the top surface of the partition on the one substrate or the other substrate, The other board is When the one substrate and the other substrate are arranged so as to face each other, the first substrate in cooperation with the one substrate and the other substrate is positioned so as to surround the first region. A sealing member disposing step of disposing a sealing member that seals a space in the region; a display medium disposing step of disposing the display medium on the one substrate or the other substrate; and after the display medium is disposed The one substrate and the other substrate are connected to the top surface of the partition wall of the one substrate and the other substrate so that the display medium is sealed in each cell with each region partitioned by the partition walls as a cell. A counter substrate disposing step of disposing the substrate so as to face the substrate, wherein the partition walls of the first pattern and the partition walls of the second pattern are discontinuous by interposing the sealing member therebetween. Anti-characteristic of being It is a manufacturing method of the type display device.

  According to the present invention, the sealing member that seals the region (first region) corresponding to the display unit of the reflective display device is provided, and the partition wall provided in the region corresponding to the display unit and the outer peripheral portion of the display unit are provided. The partition wall provided in the corresponding region (second region) is discontinuous because the sealing member is interposed between the two. In this case, since the sealing member cannot be interposed between the region corresponding to the display portion and the region corresponding to the outer peripheral portion, occurrence of a situation in which the sealing performance by the sealing member is not fully exhibited is suppressed, and the sealing member It is also suppressed that water, oxygen, or the like enters from the outside into the cell located in the region corresponding to the display portion through the partition wall that cannot intervene.

  Preferably, the second pattern is a discontinuous pattern. In this case, for example, when the partition walls are formed by a photolithography method or the like, the developer easily enters between the partition walls, and the partition walls of the second pattern are easily formed. In addition, it is not necessary to design the second pattern partition so as to form a space (cell) surrounded by continuous partition walls, that is, to ensure that the developer enters the region where the space is formed. The width of the second pattern partition can be increased with respect to the interval between the second pattern partitions. As a result, the strength of the partition walls of the second pattern can be increased.

  Since the partition provided in the region corresponding to the display unit of the display device and the partition provided on the outer periphery of the display unit are discontinuous due to the sealing member interposed therebetween, the display of the display device Intrusion of moisture, oxygen, or the like into the cell located in the region corresponding to the portion is suppressed.

FIG. 1 is a flowchart schematically showing a manufacturing method of a reflective display device according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing an example of the partition wall forming step. FIG. 3 is a diagram schematically showing an example of a partition pattern, its arrangement, and a region where a sealing member is arranged according to the first embodiment of the present invention. In FIG. 3A, the area where the sealing member is arranged is shown as a hatched portion, and in FIG. 3B, the display area equal to the area (first area) where the partition of the first pattern is formed. In FIG. 3C, the outer peripheral portion equal to the region (second region) where the partition walls of the second pattern are formed is shown as the hatched portion, and in FIG. FIG. 3 is a sectional view taken along line dd in FIG. FIG. 4 is a diagram for explaining the definition of the width of the top surface of the partition wall. FIG. 5 is a diagram schematically showing an example of the adhesive layer forming step. FIG. 6 is a diagram schematically showing an example of the display medium arranging step. FIG. 7 is a cross-sectional view showing a state where one substrate is bonded onto the other substrate in the counter substrate arranging step. FIG. 8 is a diagram schematically showing an example of a partition pattern, its arrangement, and a region where a sealing member is arranged according to the second embodiment of the present invention. In FIG. 8A, the region where the sealing member is disposed is shown as a hatched portion, and in FIG. 8B, the display is slightly larger than the region where the partition of the first pattern is formed (first region). The region is shown as a shaded portion, and in FIG. 8C, the outer peripheral portion slightly smaller than the region (second region) where the second pattern partition walls are formed is shown as the shaded portion, and FIG. FIG. 8 shows a cross-sectional view taken along the line dd of FIG. FIG. 9 is a diagram schematically showing an example of a partition pattern, its arrangement, and a region where a sealing member is arranged according to the third embodiment of the present invention. In FIG. 9A, the area where the sealing member is arranged is shown as a hatched portion, and in FIG. 9B, the display is slightly smaller than the area where the partition of the first pattern is formed (first area). In FIG. 9C, the outer peripheral portion slightly larger than the region (second region) where the partition walls of the second pattern are formed is shown as the hatched portion. Fig. 9 shows a cross-sectional view taken along the line dd of Fig. 9A. FIG. 10 is a diagram schematically showing an example of a partition pattern, its arrangement, and a region where a sealing member is arranged according to a comparative example of the present invention. In FIG. 10A, the area where the sealing member is arranged is shown as a hatched portion, and in FIG. 10B, the display area equal to the area (first area) where the partition of the first pattern is formed. In FIG. 10C, the outer peripheral portion equal to the region (second region) where the partition walls of the second pattern are formed is shown as the hatched portion, and in FIG. FIG. 10A is a sectional view taken along line dd in FIG.

  In FIG. 1 to FIG. 10, electrodes are provided on the respective surfaces of one substrate 11 and the other substrate 16, but these electrodes are not shown. In the present embodiment, one substrate 11 is disposed on the viewing side, and the other substrate 16 is disposed on the non-viewing side.

  As one substrate 11, transparent film such as polyethylene (PE), polyethylene terephthalate (PET), polyethersulfone (PES), polyethylene naphthalate (PEN), transparent glass, indium tin oxide (ITO), zinc oxide What attached | subjected transparent electrodes, such as (ZnO), can typically be used.

  The transparent electrode can be formed by a coating method, a vapor deposition method, or the like. Since the transparent electrode is used as a common electrode in the case of active matrix driving and segment driving, it is not always necessary to form a pattern, and the entire surface of the substrate may be an electrode. On the other hand, in the case of passive matrix driving, since both opposing substrates need to be pattern electrodes, the transparent electrode is also formed in a pattern such as a stripe.

  The electrode pattern can be formed by a photolithography method, a laser drawing method, an ink jet method, a screen printing method, a flexographic printing method, or the like.

  The thickness of one substrate 11 is preferably 10 μm to 1 mm. If it is thinner than 10 μm, the strength as a panel cannot be obtained and the risk of breakage increases. On the other hand, if it is thicker than 1 mm, the panel weight becomes too heavy and the handling becomes inconvenient and the cost also increases. Because. A suitable thickness range that is difficult to break and easy to handle is about 50 μm to 300 μm.

  The surface of one substrate 11 may be subjected to an oxidation preventing process by a plating process. Further, a barrier layer may be provided on the back surface (outside) of one substrate 11. The function of the barrier layer is to prevent display deterioration caused by the ink adsorbing moisture. In the present embodiment, when the barrier layer is provided on one substrate disposed on the viewing side, the barrier layer needs to be transparent and can be obtained by depositing an inorganic film. Or the film in which the barrier layer was previously formed may be bonded together.

  One substrate 11 can be applied in either a roll shape or a sheet shape.

  As the other board | substrate 16, what formed the electrode by electroconductive materials, such as a metal, on the surface, such as a resin film, a resin board, glass, epoxy glass (glass epoxy), may be used. The other substrate 16 may be a light transmissive base material. Furthermore, it may be a light-transmitting and opaque substrate, such as an opaque glass substrate, resin film, resin plate, glass, epoxy glass (glass epoxy), etc., with the other surface different from the electrode surface roughened. Can be used. In the present embodiment, the other substrate 16 is disposed at a position opposite to the viewing side, and thus is not necessarily transparent. However, when the same physical properties as the one substrate 11 such as thermal expansion characteristics are required, a transparent member similar to the one substrate 11 can be used.

  As the electrode, a pattern electrode is used in the case of segment drive and passive matrix drive, and a pixel electrode in which a TFT (Thin Film Transistor) is arranged in the case of active matrix drive.

  The thickness of the other substrate 16 is preferably 10 μm to 1 mm, similarly to the thickness of the one substrate 11. If it is thinner than 10 μm, the strength as a panel cannot be obtained and the risk of breakage increases. On the other hand, if it is thicker than 1 mm, the panel weight becomes too heavy and the handling becomes inconvenient and the cost also increases. Because. A suitable thickness range that is difficult to break and easy to handle is about 50 μm to 300 μm.

  Further functional layers can be added to the other substrate 16. For example, a barrier film can be attached to the surface of the other substrate 16. Even if a transparent film in which a barrier layer of a transparent inorganic film is previously formed by vapor deposition or the like is employed as the other substrate 16, the same function as this can be exhibited. Alternatively, an ultraviolet cut film can be attached to the surface of the other substrate 16. Even if the other substrate 16 is subjected to other ultraviolet cut processing, the same function can be exhibited. As other surface coat layers, an AG layer (antiglare layer), an HC layer (scratch prevention layer), an AR layer (antireflection layer) and the like can be added.

  The other substrate 16 can be applied in either a roll shape or a sheet shape.

  Hereinafter, an area corresponding to an area used for a predetermined display in a reflective display device manufactured using one substrate 11 and the other substrate 16 on one substrate 11 or the other substrate 16 is displayed. An area around the display area is referred to as an “outer peripheral portion”.

<Method for manufacturing reflective display device>
FIG. 1 is a flowchart schematically showing a manufacturing method of a reflective display device according to the first embodiment of the present invention.

  FIG. 2 is a diagram schematically showing an example of the partition wall forming step. As shown in FIG. 2, first, a partition wall having a predetermined pattern is formed on the upper surface of one substrate 11 generally placed in a horizontal direction by, for example, photolithography (exposure by ultraviolet (UV) irradiation → development → firing). 12 is formed. The partition wall 12 is a member that defines a plurality of cells to be described later at least in the display region 60.

  The partition wall 12 can be composed of an ultraviolet curable resin, a thermosetting resin, a room temperature curable resin, or the like. As a method for forming the partition wall 12, a mold transfer method such as embossing can be adopted in addition to the photolithography method. Further, a method of manufacturing a structure having a desired pattern as a partition and sticking the structure to one substrate 11 may be employed.

  The partition wall 12 includes the display area 60 or is formed in a first pattern in an area included in the display area 60 (hereinafter referred to as “first area”). A region including at least a part of a region that is not used for a desired display on the substrate (hereinafter referred to as “second region”) is formed in a second pattern. In the present embodiment, the first area and the display area 60, and the second area and the outer peripheral portion 70 coincide with each other as shown in FIGS. 3 (b) and 3 (c).

  In the specification and claims of the present application, the meaning of the term “(first) region including all of the display region” means “(first) region including the display region as a part thereof”). In addition to the meaning, the meaning of “(first) area that matches the display area” as shown in FIG. 3 is also included.

  In the present embodiment, as shown in FIG. 3, the pattern of the partition wall 12 is a grid pattern as a whole in the region corresponding to the display region 60, and the second pattern in the region corresponding to the outer peripheral portion 70. As a dot array pattern. In addition, in order to prevent moisture, oxygen, and the like from entering from the outside through the partition wall 12 and the adhesive layer 22 into the cell constituted by the first pattern partition wall 121, the first pattern partition wall 121 and the second pattern partition wall The partition wall 122 is not continuous.

  The width of the top face of the first pattern partition wall 121 is 9 μm to 50 μm, preferably 9 μm to 20 μm. 9 μm is the lower limit of the line width at which the partition wall 12 can be patterned without falling down. When the width of the top surface of the partition wall 12 is less than 9 μm, in a pattern in which the length of the partition wall 12 is 60 μm or more, at least a part of the partition wall 12 falls, peels off, or the separated partition wall 12 moves over the substrate. Or move. In that case, the function of preventing the movement of particles by the partition wall 12 is lost, and the display quality is deteriorated. On the other hand, the upper limit of 50 μm, which is the upper limit of the preferred range, is an upper limit at which the partition wall 12 is not too conspicuous when visually observed.

  Here, the definition of the width of the top surface of the partition 12 is shown in FIG. If the corners of the top surface are not rounded, the width of the top surface is defined as it is, as shown in FIGS. 4 (a) and 4 (b). On the other hand, when the corner of the top surface is rounded, as shown in FIGS. 4C and 4D, it is understood as the width between the intersection lines of the extended surface of the top surface and the extended surface of the wall portion. Is done. As a measuring method for evaluation, one substrate 11 on which the partition wall 12 was formed was embedded in a curable resin, and a cross section of the partition wall 12 was cut out by a microtome (Daiwa Kogyo Kogyo Co., Ltd .: FX-801). Each width can be measured based on an image taken by a scanning electron microscope (SEM).

  On the other hand, the width of the top surface of the partition wall 122 of the second pattern is 5 μm to 200 μm, preferably 10 μm to 100 μm. In the case where the width of the top surface of the partition wall 122 is less than 5 μm, even if the length of the partition wall 122 is short, a part of the partition wall 122 falls or peels off, or the separated partition wall 122 moves on the substrate.

  The shape of the first pattern 121 arranged in the display region 60 is basically arbitrary, such as a circle, a lattice, a honeycomb shape (hexagon), and other polygons. The aperture ratio is preferably 70% or more, and particularly preferably 90% or more. The higher the aperture ratio, the wider the displayable area, so that high contrast can be obtained.

  In addition, the shape of the second pattern is basically arbitrary, and besides the circle, lattice, honeycomb (hexagon), other polygons, and combinations thereof, the cell structure as in the present embodiment A pattern that is not formed can also be used. This is because the partition walls 122 of the second pattern are basically disposed outside the display area 60. Therefore, the second pattern may be a discontinuous pattern as shown in FIG. 3. In this case, the lower limit value of the interval between the divided portions of the partition 122 (the interval between the adjacent partitions 122) is Considering the limit of patterning, it is 10 μm. Further, the upper limit value of the distance between the divided portions of the partition wall 122 (interval between adjacent partition walls 122) is 100 times the partition wall height (3 mm when the partition wall height is 30 μm), and is higher than this. The cell gap cannot be maintained.

  The thickness of a partition is 5-50 micrometers, Preferably it is 10-50 micrometers. If the thickness is 5 μm or less, the amount of ink to be filled is small, and sufficient display characteristics, in particular, contrast cannot be obtained. On the other hand, if the thickness is 50 μm or more, the panel is too thick and the drive voltage increases excessively. From the viewpoint that good display characteristics can be obtained at a low driving voltage, a thickness in the range of 10 to 50 μm is preferable.

  The cell size (pitch L) depends on the size of the display panel, but is 0.05 to 1 mm, preferably 0.1 to 0.5 mm. Here, as shown in FIG. 3A, the pitch means the distance L between the center points of adjacent cells, that is, the distance necessary to move adjacent cells to overlap each other.

  Next, the adhesive layer 22 is formed on the partition wall 12 (adhesive layer forming step: step (2) in FIG. 1). In this adhesive layer forming step, for example, a heat sealing agent such as a polyester-based thermoplastic adhesive is formed with a thickness of 1 to 100 μm by a transfer method or a printing method. Preferably, it is formed with a thickness of 1 to 50 μm, and particularly preferably with a thickness of 1 to 20 μm.

  Supplementing a specific description of an example of a typical thermal transfer method as a transfer method, as shown in FIG. 5, a heat seal agent 221 such as a polyester-based thermoplastic adhesive having a thickness of 20 μm on a PET film 21, for example. Is prepared, and the surface of the heat sealant 221 of the transfer sheet 20 is laminated on the partition wall at a normal temperature and a pressure of 1 kPa. This is heated for 1 minute on a hot plate maintained at, for example, 120 ° C., which is equal to or higher than the softening temperature of the heat sealant 221, and then the transfer sheet 20 is peeled off. Thereby, an adhesive layer 22 of about 6 μm, for example, is formed on the partition wall.

  The adhesive layer 22 is preferably made of a thermoplastic material such as the heat sealant 221, which has the property of softening by heating and solidifying when cooled, and is plastic when it is repeatedly cooled and heated. Is a material that is reversibly maintained.

  When a heat sealant made of a thermoplastic material is used as the adhesive layer 22, the heat sealant solidified on the transfer sheet substrate is softened by heating to a temperature exceeding the softening temperature, and the partition wall The heat sealant can be reliably thermally transferred only to the upper surface. Moreover, since the heat sealant after heat transfer is cooled to room temperature and solidified again, tackiness, that is, stickiness, is eliminated. Further, since there is no tack or stickiness, the display medium filled in the cell does not adhere to the heat sealant. Then, the heat sealing agent on the upper surface of the partition wall is heated again to a temperature exceeding the softening temperature to be softened, so that it has tackiness, that is, stickiness, so that it is securely bonded to the other substrate. Since the heat sealant after bonding to the other substrate is not tacky, that is, sticky at normal temperature again, the display medium will not adhere to the heat sealant, and there is no risk of deterioration in display quality. .

  Specifically, thermoplastic base polymers such as ethylene-vinyl acetate copolymer, polyester, polyamide, polyolefin, polyurethane, natural rubber, styrene-butadiene block copolymer, styrene-isoprene block copolymer, styrene-ethylene. A resin mainly composed of a thermoplastic elastomer such as a butylene-styrene block copolymer or a styrene-ethylene-propylene-styrene copolymer, and a tackifier resin or a plasticizer is mainly used.

  In order to increase the adhesion between the partition wall 12 and the heat sealant 221, the partition wall 12 may be subjected to surface treatment by ultraviolet irradiation, plasma treatment, or the like, or a primer may be formed. Alternatively, a silane coupling agent may be added to the heat seal agent 221.

  In the present embodiment, the adhesive layer forming step is performed on the top surface of the partition wall, but in the sealing member disposing step described later, the sealing disposed on the outer periphery of the display region 60 formed on one substrate 11 is performed. Since each panel is sealed and bonded by the member 61, the adhesive layer forming step on the top surface of the partition wall can be omitted.

  Next, a sealing member 61 that prevents intrusion of moisture and oxygen from the outside of the display region 60 into the display region 60 is provided on the outer periphery of the display region 60 formed on the one substrate 11. When the top surface of the first substrate and the other substrate 16 are bonded, the space on the first region can be sealed together with the one substrate 11 and the other substrate 16 (sealing member). Arrangement step: step (3) in FIG. When one substrate 11 includes a plurality of display areas 60, the sealing member 61 is disposed on the outer periphery of each of the plurality of display areas 60.

  If a specific description is supplemented about an example of the arrangement method of the sealing member 61, the sealing member 61 is made of an adhesive such as an ultraviolet curable resin with a line width of 0.5 mm and a height of 50 μm using a dispenser. It arrange | positions by apply | coating to linear form.

  The sealing member 61 can be composed of a thermosetting resin, a room temperature curable resin, a heat seal resin, or the like in addition to the ultraviolet curable resin. In addition to the dispenser, the sealing member 61 can be arranged by various printing methods or thermocompression bonding, and may be arranged on the other substrate 16.

  In addition, the sealing member 61 needs to be arrange | positioned so that the outer surface of the 1st pattern partition 121 located in the outermost periphery of a 1st area | region may not be exposed to the environment where moisture, oxygen, etc. exist outside the 1st area | region. is there. Otherwise, moisture, oxygen, and the like will enter the first region, that is, the cell in the display region 60 through the partition 121 of the first pattern and the adhesive layer 22 provided on the top thereof. The invention makes no sense in principle.

  Next, the ink 13 as a display medium is arranged on the other substrate 16 (display medium arrangement step: step (4) in FIG. 1). FIG. 6 is a diagram schematically showing an example of the display medium arranging step. Here, (1) the ink 13 is dropped from the dispenser 31 or inkjet or die coat (ink dropping step), and (2) the ink 13 is made uniform in the surface by the applicator 32 or doctor blade, doctor knife, and central squeegee. It is applied (ink application process). The ink 13 may be disposed on one substrate 11.

  As the display medium, a display medium containing at least one or more kinds of electrically responsive materials can be used. Examples of the electroresponsive material include a charged particle material and a liquid crystal material, and the charged particle material includes a so-called electrophoretic material in which colored particles such as white, black, and color move in response to an electric field, or two particles. There are materials typified by twist balls that are color-coded and rotated by an electric field, or nanoparticle materials that move by an electric field. On the other hand, the liquid crystal material includes a material for electrically controlling transmission and scattering known as PDLC (Polymer Dispersed Liquid Crystal), a material in which a liquid crystal is mixed with a dye, a cholesteric liquid crystal material, and the like. These materials that have electrical responsiveness and change optical characteristics need to be isolated into cells regardless of the type, and are subject to application of the present invention.

  Thereafter, the adhesive layer 22 or the sealing member 61 on the partition wall 12 is bonded to the other substrate 16 facing the one substrate 11 (opposing substrate placement step: step (5) in FIG. 1). Thereby, the display medium (ink 13) is sealed in each cell.

  In the counter substrate placement step, as shown in FIG. 7, the heat sealing agent 221 or the sealing member 61 applied as the adhesive layer 22 is heated to obtain an adhesive force. Specifically, while applying a predetermined thermocompression pressure (laminate pressure) by the laminator 91, the heat sealant 221 or the sealing member 61 of the adhesive layer 22 is heated from the periphery to a temperature exceeding the softening temperature to be softened. Thus, the partition wall 12 and the other substrate 16 coated with the ink 13 are bonded. However, other thermocompression bonding modes may be employed.

  In the counter substrate placement step, one substrate 11 is curled so that no bubbles remain in the cell between one substrate 11 and the other substrate 16, and from one side (left side in the case of FIG. 7). A portion where one substrate 11 and the other substrate 16 are pressed against each other by the laminator 91 is moved toward the opposite side (in the case of FIG. 7, the right side), and excess ink on the other substrate 16 is removed. Then, they are stuck together while being pushed out from the area surrounded by the sealing member 61. Thereafter, the sealing member 61 is cured to seal the outer periphery of the display region, and the mother panel substrate 81 is manufactured.

  Thereafter, as shown in FIG. 1, the mother panel substrate 81 is cut into a predetermined size by a cutting device 51 such as a guillotine, an upper blade sliding device, a laser cutting device, a laser cutter, etc., and a desired reflective display device is manufactured. Complete.

  In the specification and claims of this application, the term “mother panel substrate” means a portion used as a display panel in a reflective display device (display area 60 or display area 60 and display). A portion that coincides with a region including the outer peripheral portion 70 (frame portion) within a predetermined range from the edge portion of the region 60 (hereinafter referred to as a “panel portion”). A panel substrate having

  As described above, according to the present embodiment, the sealing member 61 that seals the region (first region) corresponding to the display unit of the reflective display device is provided, and is provided in the region corresponding to the display unit. The partition wall 121 and the partition wall 122 provided in the region (second region) corresponding to the outer peripheral portion of the display unit are discontinuous due to the sealing member 61 interposed therebetween. In this case, since the sealing member 61 cannot be interposed between the region corresponding to the display portion and the region corresponding to the outer peripheral portion thereof, occurrence of a situation in which the sealing performance by the sealing member 61 is not fully exhibited is suppressed. In addition, it is also possible to prevent moisture, oxygen, and the like from entering the cell located in the region corresponding to the display unit through the partition wall where the sealing member 61 cannot be interposed.

  The second pattern is a discontinuous pattern. In this case, for example, when the partition walls are formed by a photolithography method or the like, the developer easily enters between the partition walls, and the partition walls 122 having the second pattern are easily formed. In addition, it is not necessary to design the second pattern partition 122 so that a space (cell) surrounded by the continuous partition is formed, that is, so that the developer enters the region where the space is formed. Therefore, the width of the second pattern partition 122 can be increased with respect to the interval between the second pattern partitions 122. As a result, the strength of the second pattern partition 122 can be increased.

  In addition, when the heat sealant 221 of the adhesive layer 22 is made of a thermoplastic material, it does not have tack or stickiness at room temperature, so that it is very easy to handle. Further, since there is no tack, that is, stickiness, the subsequent display medium arranging step is easy. Specifically, even if the display medium is arranged using a squeegee, a doctor blade, a doctor knife, or the like, the display medium (ink 13) does not adhere to the heat sealant 221.

  In addition, when a predetermined electric field (voltage) is applied between an electrode (not shown) of one substrate 11 and an electrode (not shown) of the other substrate 16, an electrically responsive material in the ink 13 as a display medium. Is driven and predetermined information such as a character pattern is displayed. Thereafter, even if the electric field is no longer applied, the information display state is maintained until a new electric field is applied between the two substrates.

  Next, a second embodiment of the reflective display device according to the present invention will be described with reference to FIG.

  FIG. 8 is a diagram schematically showing an example of the partition pattern, its arrangement, and the region where the sealing member 61 is arranged according to the second embodiment of the present invention. In the present embodiment, as shown in FIG. 8, on one substrate 11, only a part of the display area 60 (area used for predetermined display on one substrate 11) is included and is slightly smaller than the display area 60. A second that has a predetermined first pattern in a small first area and includes the outer peripheral part 70 (an area not used for predetermined display on one substrate 11) around the display area 60 and is slightly larger than the outer peripheral part 70. A partition wall 12 is formed in a predetermined second pattern in the region. Moreover, the partition 121 in the first region and the partition 122 in the second region are discontinuous. Further, on one substrate 11, a sealing member 61 is arranged so as to surround only a part of the display area 60 and surround an area slightly smaller than the display area 60.

  Other configurations are substantially the same as those of the first embodiment shown in FIG. In FIG. 8, the same parts as those of the first embodiment shown in FIG.

  In the present embodiment, the first region where the first pattern of the partition wall 121 is formed is slightly smaller than the display region 60. However, if the first region and the region surrounded by the sealing member 61 cover most of the display region 60, the same effects as those of the first embodiment can be obtained.

  Next, a third embodiment of the reflective display device according to the present invention will be described with reference to FIG.

  FIG. 9 is a diagram schematically showing an example of the partition pattern, its arrangement, and the region where the sealing member 61 is arranged according to the third embodiment of the present invention. In the present embodiment, as shown in FIG. 9, on one substrate 11, a first region that includes a display region 60 (region used for predetermined display of one substrate 11) and is slightly larger than the display region 60. A second pattern which is a predetermined first pattern and includes only a part of the outer peripheral portion 70 (the region not used for the predetermined display of one substrate 11) around the display region 60 and is slightly smaller than the outer peripheral portion 70. A partition wall is formed in the region with a predetermined second pattern. Moreover, the partition wall 121 in the first region and the partition wall 122 in the second region are discontinuous, and the sealing member 61 is disposed on the outer periphery of the first region.

  Other configurations are substantially the same as those of the first embodiment shown in FIG. In FIG. 9, the same parts as those in the first embodiment shown in FIG.

  In the present embodiment, the first area in which the first pattern partition 121 is formed is slightly wider than the display area 60. Therefore, the display area 60 is located inside the sealing member 61, and the partition walls 121 and 122 are discontinuous between the inside and the outside of the area surrounded by the sealing member 61. Intrusion of oxygen or the like is suppressed, and the same effect as that of the first embodiment can be obtained.

  Next, practical examples actually performed will be described.

<Example of Reflective Display Device>
<Example>
As one substrate 11, an indium tin oxide (ITO) vapor deposition film (thickness 0.2 μm) was provided as a transparent electrode on one surface of a 300 mm × 400 mm × 0.1 mm thick PET film (Toyobo A4100). A substrate was prepared. The transparent electrode is formed by a general film formation method such as sputtering, vacuum evaporation, or CVD, and is also formed by zinc oxide (ZnO), tin oxide (SnO), etc. in addition to indium tin oxide (ITO). obtain. Two display areas 60 are defined on one substrate 11.

Next, a negative photosensitive resin material (DuPont MRC Dry Film Resistry Dry Film Resist) is laminated on the one substrate 11 to a thickness of 30 μm and heated at 100 ° C. for 1 minute. Then, exposure is performed using an exposure mask (exposure amount: 500 mJ / cm ² ), and thereafter development using a 1% KOH aqueous solution is performed for 30 seconds, and baking is performed at 120 ° C. for 60 minutes. As shown, a grid pattern (first pattern) partition 121 having a cell pitch of 300 μm is formed in a region corresponding to the display region 60, and a dot arrangement pattern (second pattern) partition 122 is formed in a region corresponding to the outer peripheral portion 70. It was.

  A polyethylene terephthalate (PET) film (manufactured by Teijin DuPont) having a thickness of 50 μm is used as the transfer sheet substrate 21, and a heat sealant 221 (Byron 630 manufactured by Toyobo Co., Ltd.) having a thickness of 20 μm is applied by a die coder. And dried. Thereby, a roll-shaped transfer sheet 20 having an adhesive layer of 20 μm was produced. The softening temperature of the heat sealant 221 was about 110 ° C.

  Then, with the transfer sheet 20 placed on the upper surface of the partition wall 12, the periphery of the heat sealant 221 is heated to a temperature exceeding its softening temperature, for example, about 120 ° C. while further applying a pressing force of about 1 kPa. As a result, the heat sealant 221 was thermally transferred to the entire top surface of the partition wall 12. The height from the top surface of the partition wall 12 to the top of the heat sealant 221 was about 10 μm on the first pattern partition wall 121 and about 7 μm on the second pattern partition wall 122.

  Subsequently, an ultraviolet curable resin (manufactured by ThreeBond Co., Ltd .: acrylic sealant 3052D) is applied to the outer periphery of each of the two display areas 60 using a dispenser, and the sealing member 61 has a line width of 1.0 mm. And a height of 100 μm.

  Next, as the other substrate 16, a non-alkali glass (OA-10G manufactured by Nippon Electric Glass Co., Ltd.) having a size of 300 mm × 400 mm × thickness 0.5 mm and various electrodes such as Cu electrodes formed in a pattern were used. . Various electrode patterns were formed by a general etching method. In this embodiment, an active matrix driving electrode pattern corresponding to a driving electrode of a panel corresponding to 6 inches corresponds to the two display regions 60 defined on the one substrate 11, and the other substrate 16. It was formed on the two sides.

  Subsequently, the ink 13 having the following components is used as a display medium, dropped from the dispenser 31, and applied with an applicator 32 (manufactured by Tester Sangyo) with a gap of 50 μm from the surface of the other substrate 16. Ink 13 was applied on the substrate 16. The coating was performed at a position of 300 mm × 400 mm with the center of the other substrate 16 as a reference, and the film thickness was 35 μm.

<Ink component>
Electrophoretic particles (titanium dioxide): 60 parts by weight Dispersion: 40 parts by weight And, in the atmosphere, the adhesive layer 22 on the partition wall 12 of one substrate 11 is formed on the other substrate 16. Overlapping, the partition 12 of one substrate 11 and the other substrate 16 were brought into close contact with each other while further applying a constant thermocompression pressure by a laminator 91 (see FIG. 7). At this time, one substrate 11 is curled and sealed from one side of one substrate 11 and the other substrate 16 toward the other side facing each other so that no bubbles remain between the two substrates. Bonding was performed while extruding excess ink exceeding the volume of the space surrounded by the member 61. As a result, only a specified amount of ink was filled in the cell.

  The temperature at the time of thermocompression bonding is 111 ° C. to 150 ° C., preferably 110 ° C. to 120 ° C., higher than the softening temperature or melting temperature of the adhesive layer 22, and 110 ° C. in this example. The thermocompression bonding pressure is preferably from 0.01 MPa to 0.7 MPa, particularly preferably from 0.1 MPa to 0.4 MPa, and in this example, it was 0.4 MPa.

Thereafter, the sealing member 61 was cured by exposing to ultraviolet rays (exposure amount: 3000 mJ / cm ² ).

  The mother panel substrate 81 manufactured as described above was cut into a predetermined size by the cutting device 51, and a display panel was manufactured.

  The display panel obtained as described above was subjected to a heat shock test (30 minutes in an environment of −20 ° C. and 30 minutes in an environment of 80 ° C., and this was repeated for 10 cycles). Was very good, the in-plane color difference during white display and black display satisfied ΔE ≦ 3, and no generation of bubbles was observed.

<Comparative example>
In contrast to the embodiment, as shown in FIG. 10, the partition 12 is formed in a lattice shape as a whole across the display region 60 and the outer peripheral portion 70, that is, the partition in the region (first region) corresponding to the display region 60. 121 and the partition 122 of the area | region (2nd area | region) corresponding to the outer peripheral part 70 were formed in the continuous state, and the others were the same processes, and produced the display panel.

  The display panel obtained as described above was subjected to a heat shock test under the same conditions as those of the display panel of the above example, and the display quality was evaluated, but the display quality was low, and the in-plane color difference during white display and black display Did not satisfy ΔE ≦ 3, and generation of bubbles was also confirmed. This is because the partition walls 121 and 122 are continuous, so that moisture, oxygen, and the like have entered the cell formed in the display region 60 through the partition wall or the adhesive layer 22 formed on the top surface thereof. Conceivable.

11 One substrate 12 Partition 121 First pattern partition 122 Second pattern partition 13 Ink (display medium)
16 Other substrate 22 Adhesive layer 221 Heat seal agent 31 Dispenser 32 Applicator 51 Cutting device 60 Display area 61 Sealing member 70 Outer peripheral portion 81 Mother panel substrate 91 Laminator

Claims (4)

A display medium containing at least one or more kinds of electrically responsive materials is sealed between two opposing substrates, at least one of which is transparent and each has electrodes, and a predetermined electric field is interposed between the two substrates. A reflective display device in which the display medium performs a predetermined display when
On one substrate, a display area used for a predetermined display on the one substrate is included, or a first pattern is included in a first area included in the display area on the one substrate, and the first A partition wall is formed in a second pattern in a second region that includes at least a part of a region that is around one region and is not used for predetermined display of the one substrate,
The display medium is arranged with each area defined by the partition walls of the first pattern in the display area of the one substrate as a cell,
A sealing member disposed between the one substrate and the other substrate so as to surround the first region, and sealing the space on the first region together with the one substrate and the other substrate. Provided,
The reflective display device according to claim 1, wherein the partition walls of the first pattern and the partition walls of the second pattern are discontinuous because the sealing member is interposed therebetween. The reflective display device according to claim 1, wherein the second pattern is a discontinuous pattern. A display medium containing at least one or more kinds of electrically responsive materials is sealed between two opposing substrates, at least one of which is transparent and each has electrodes, and a predetermined electric field is interposed between the two substrates. A method of manufacturing a reflective display device, wherein the display medium displays a predetermined display when
On one substrate, a display area used for a predetermined display on the one substrate is included, or a first pattern is included in a first area included in the display area on the one substrate, and the first A partition wall forming step of forming a partition wall in a second pattern in a second region that includes at least a part of a region that is around one region and is not used for predetermined display of the one substrate;
When the one substrate and the other substrate are arranged on the one substrate or the other substrate so that the top surface of the partition wall of the one substrate faces the other substrate. A sealing member disposing step of disposing a sealing member that seals the space on the first region in cooperation with the one substrate and the other substrate at a position that can surround the first region;
A display medium disposing step of disposing the display medium on the one substrate or the other substrate;
The one substrate and the other substrate are connected to the one substrate so that the display medium is sealed in each cell, with each region partitioned by the partition wall after the display medium is disposed as a cell. A counter substrate arrangement step of arranging the top surface of the partition wall and the other substrate to face each other;
With
The method for manufacturing a reflective display device, wherein the partition walls of the first pattern and the partition walls of the second pattern are discontinuous because the sealing member is interposed therebetween. The method of manufacturing a reflective display device according to claim 3, wherein the second pattern is a discontinuous pattern.

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