JP2006154655A - Method for manufacturing information display panel, and information display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an information display panel by which an adhesive applied on an upper face of a barrier wall is effectively prevented from oozing into a cell. <P>SOLUTION: The information display panel is manufactured by: forming a plurality of cells partitioned by barrier walls between two opposing substrates one of which is transparent; encapsulating at least one kind or more of display media comprising at least one kind or more of particles in the cells; and displaying information by moving the display media by an electric field generated within the substrates. In the method for manufacturing the information display panel, after finishing an adhesive layer forming step of applying an adhesive on the upper face of the barrier walls 4 and before a pressing step of laminating the two substrates, the adhesive applied on the upper face of the barrier walls 4 is slightly cured, and then the adhesive applied on the upper face of the barrier walls is further cured in the pressing step so as to effectively prevent the adhesive from oozing into the cell. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the present invention, a plurality of cells partitioned by partition walls are formed between two opposing substrates, at least one of which is transparent, and at least one kind of display composed of at least one kind of particles in the cell. The present invention relates to a method for manufacturing an information display panel that displays information by enclosing a medium and moving a display medium by an electric field generated in a substrate, and an information display device that includes the information display panel.

  2. Description of the Related Art Conventionally, information display devices that use technologies such as electrophoresis, toner (particle) transfer, electrochromic, thermal, and two-color particle rotation have been proposed as information displays that replace liquid crystal (LCD). Yes.

  Compared to LCDs, these conventional technologies have advantages such as a wide viewing angle close to that of ordinary printed materials, low power consumption, and a memory function. It is considered as a technology that can be used for mobile phones, and is expected to expand to information display for mobile terminals, electronic paper, and the like. In particular, recently, an electrophoretic method (for example, see Non-Patent Document 1) in which a dispersion liquid composed of dispersion particles and a colored solution is microencapsulated and disposed between opposing substrates has been proposed and expected. It has been.

  However, the electrophoresis method has a problem that the response speed becomes slow due to the viscous resistance of the liquid because the particles migrate in the liquid. In addition, since particles with high specific gravity such as titanium oxide are dispersed in a solution with low specific gravity, it is easy to settle, and it is difficult to maintain the stability of the dispersed state, and there is a problem that the stability of repeated information display is lacking. ing. Even when microencapsulation is performed, the cell size is set to the microcapsule level, and the above-described drawbacks are hardly made to appear, and the essential problems are not solved at all.

  On the other hand, a method in which conductive particles and a charge transport layer are incorporated into a part of a substrate without using a solution is proposed instead of an electrophoresis method using behavior in a solution (see, for example, Non-Patent Document 1). ). However, this method has a problem that the structure is complicated because the charge transport layer and further the charge generation layer are arranged, and that it is difficult to inject the charges into the conductive particles, so that the stability is lacking. .

  As a method for solving the various problems described above, a plurality of cells partitioned by a partition are formed between two opposing substrates, at least one of which is transparent, and at least one kind of particles are formed in the cells. There is known an information display device in which at least one type of display medium composed of the above is enclosed and the display medium is moved by an electric field generated in a substrate to display information. An information display panel used in such an information display device is manufactured by bonding one substrate having an adhesive applied to the upper surface of a partition wall (spacer) and the other substrate.

趙 Kuniori and three others, “New Toner Display Device (I)”, July 21, 1999, Annual Meeting of the Imaging Society of Japan (83 times in total) “Japan Hardcopy’99”, p.249-252

  In the above-described conventional method for manufacturing an information display panel, the adhesive applied to the upper surface of the partition wall is not subjected to a thermosetting process, and a pressing process is performed to bond the two substrates immediately after applying the adhesive. Therefore, the adhesive applied to the upper surface of the partition wall may ooze out so as to enter the cell partitioned by the partition wall. If such adhesive oozes out to a deep position in the cell, the bonded state of the two substrates becomes defective (NG) in the pressing process.

  The present invention provides a method for manufacturing an information display panel that can effectively prevent the adhesive applied to the upper surface of a partition wall from leaking into a cell, and an information display device using the information display panel. With the goal.

  In order to achieve the above object, a method for manufacturing an information display panel according to the present invention includes forming a plurality of cells partitioned by a partition wall between two opposing substrates, at least one of which is transparent, and at least inside the cell. A method for manufacturing an information display panel in which at least one type of display medium composed of one or more types of particles is encapsulated and the display medium is moved by an electric field generated in a substrate to display information. After completion of the adhesive layer forming process to apply the adhesive on the upper surface, before the pressing process to bond the two substrates, the adhesive applied to the upper surface of the partition wall is slightly cured and applied to the upper surface of the partition wall in the pressing process. The cured adhesive is fully cured.

  In the method for producing an information display panel of the present invention, the solvent insolubility before the pressing step is 5 to 80 wt% as an indicator of slight curing (provided that the solvent insolubility (%) = (B / A) × 100, A: weight before immersion of the adhesive in the solvent, B: weight after immersion of the adhesive in a good solvent at 25 ° C. for 24 hours) The adhesive is a hybrid adhesive of an ultraviolet curable adhesive and a thermosetting adhesive, an epoxy adhesive using two or more kinds of curing agents having different curing temperatures, and a two-component curable epoxy adhesive It is preferable that the adhesive is any one of ultraviolet curable adhesives.

  According to the method for manufacturing an information display panel of the present invention, a plurality of cells partitioned by a partition are formed between two opposing substrates, at least one of which is transparent, and at least one or more types are formed in the cells. When manufacturing an information display panel in which at least one type of display medium composed of particles is sealed and the display medium is moved by an electric field generated in the substrate to display information, an adhesive is applied to the upper surface of the partition wall. After the completion of the adhesive layer forming process for applying the adhesive, before the pressing process for bonding the two substrates, the adhesive applied to the upper surface of the partition wall is slightly cured, and the adhesive applied to the upper surface of the partition wall in the pressing process is applied. Since the main curing is performed, the adhesive applied to the upper surface of the partition wall is slightly hardened and difficult to bleed out during the pressing process, so that the adhesive applied to the upper surface of the partition wall is effectively leached into the cell. Method of manufacturing the information display panel capable of preventing can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  First, the structure of the information display panel manufactured by the manufacturing method of the present invention will be described. In the information display panel manufactured by the method of the present invention, an electric field is applied by some means in the substrate of the information display panel in which the display medium is sealed between the opposing substrates. The display medium charged according to the electric field direction is attracted by an electric field force or a Coulomb force, and the display medium reciprocates by switching the electric field direction, thereby displaying information. Therefore, it is necessary to design the information display panel so that the display medium can move uniformly and maintain stability during repetition or storage. Here, as the force applied to the particles constituting the display medium, in addition to the force attracted by the Coulomb force between the particles, an electric image force with the electrode, an intermolecular force, a liquid cross-linking force, gravity and the like can be considered.

An example of an information display panel applicable to the information display device of the present invention will be described with reference to FIGS.
In the example shown in FIG. 1, at least two or more kinds of display media 3 composed of at least one kind of particles (here, a white display medium 3W composed of particle groups and a black display medium 3B composed of particle groups are shown). ) Is moved perpendicularly to the substrates 1 and 2 according to the electric field applied from the outside of the substrates 1 and 2, and the black display medium 3B is visually recognized by the observer to display black, or a white display medium 3W is visually recognized by an observer and white display is performed. In the example shown in FIG. 1, for example, a partition 4 is provided between the substrates 1 and 2 in a lattice shape to form a display cell.
In the example shown in FIG. 2, at least two or more kinds of display media 3 composed of at least one kind of particles (here, a white display medium 3 </ b> W composed of particle groups and a black display medium 3 </ b> B composed of particle groups are shown). ) Is moved perpendicularly to the substrates 1 and 2 in accordance with the electric field generated by applying a voltage between the electrode 5 provided on the substrate 1 and the electrode 6 provided on the substrate 2, and the black display medium 3B is moved. The observer visually recognizes and displays black, or the white display medium 3W is visually recognized by the observer and displays white. In the example shown in FIG. 2, for example, a partition 4 is provided between the substrates 1 and 2 in a lattice shape to form a display cell.
In the example shown in FIG. 3, an electrode provided on a substrate 1 with a display medium 3 having at least one color composed of at least one kind of particles (here, a white display medium 3 </ b> W consisting of a group of particles) is provided. In accordance with the electric field generated by applying a voltage between the electrode 5 and the electrode 6, the substrate 1 and 2 are moved in the horizontal direction, the white display medium 3W is visually recognized by the observer, or white display is performed. Alternatively, the color of the electrode 5 or the substrate 1 is displayed by the observer by visually recognizing the color of the electrode 5 or the substrate 1. In the example shown in FIG. 3, for example, a grid-like partition wall 4 is provided between the substrates 1 and 2 to form a display cell.
The above description is similarly applied to the case where the white display medium 3W including the particle group is replaced with the white display medium including the powder fluid and the black display medium 3B including the particle group is replaced with the black display medium including the powder fluid. be able to.

Hereinafter, a method for manufacturing an information display panel, which is a feature of the present invention, will be described in detail. The information display panel of the present invention includes a plurality of cells partitioned by partition walls between two opposing substrates, at least one of which is transparent, and at least one type of particles in the cell. An information display panel that encloses one or more types of display media and moves the display media by an electric field generated in two substrates to display information. By the following steps (1) to (8) Make it. In addition, since processes other than (5), (7), and (8) are the same as the prior art, detailed description is omitted.
(1) Partition (rib) and electrode pattern forming process on the substrate (the latter is performed only when an electrode is required)
(2) Step of filling display substrate onto substrate (3) Step of removing unnecessary display medium on partition (4) Step of forming adhesive layer on partition (This adhesive layer forming step is a step of filling the display medium) May be done before)
(5) Fine curing (gelation) process of adhesive layer (6) Overlaying process of alignment (7) Bonding process of two substrates (including main curing process of adhesive)
(8) Inspection process to evaluate the bleeding quality of adhesive

  As the adhesive used in the adhesive layer forming step, it is preferable to use various reactive adhesives such as an epoxy adhesive and an acrylic adhesive. More specifically, as the adhesive, a hybrid adhesive of an ultraviolet curable adhesive and a thermosetting adhesive, an epoxy adhesive using two or more kinds of curing agents having different curing temperatures, a two-component curable epoxy adhesive, an ultraviolet retardation It is preferable to use any of curable adhesives.

In the method for manufacturing an information display panel according to the present invention, in the step (5) of finely curing (gelling) the adhesive layer, adhesion applied to the upper surface of the partition wall of the substrate on which the partition wall is formed (hereinafter referred to as a ribbed substrate). The agent is slightly cured (gelled). As a method, (a) the ribbed substrate is left at room temperature for a predetermined time (for example, 10 to 30 minutes), and (b) the adhesive layer of the ribbed substrate has a predetermined strength ( For example, using a method of irradiating ultraviolet rays of 1000 to 2000 mJ / cm ² ) or (c) preheating the ribbed substrate in a thermal circulation oven at, for example, 65 to 80 ° C. for 60 minutes, an indicator of fine curing As the solvent insolubility before the pressing step is 5 to 80 wt% (however, the solvent insolubility (%) = (B / A) × 100, A: the weight of the adhesive before immersion in the solvent, B: adhered in a good solvent) (Weight after immersion for 24 hours at 25 ° C) The adhesive shall be slightly cured.

  Further, in the bonding step of two substrates (including the main curing step of the adhesive) of (7), the adhesive is fully cured by performing hot pressing at a predetermined pressure and a predetermined temperature, and the adhesive of (8) In the inspection process for evaluating the quality of seepage, the “seepage judgment” set on the cell side from the boundary between the partition wall and the cell as shown in FIG. If the exudation falls within the range of 5 μm, which is the “standard value”, it is evaluated as good (OK), and as shown in FIG. 4B, the “exudation determination” set on the cell side from the boundary between the partition wall and the cell. If exudation occurs outside the range of 5 μm which is the “standard value”, it is evaluated as defective (NG).

  According to the method for manufacturing an information display panel of the present invention, after the adhesive layer forming step of applying an adhesive on the upper surface of the partition wall, before the pressing step of bonding the two substrates, the above (1) to ( 4) The adhesive applied to the upper surface of the partition wall is slightly cured by any of the methods, and the adhesive applied to the upper surface of the partition wall in the pressing process is fully cured. Applied to the upper surface of the partition wall as shown in Examples 1 to 7 (corresponding to the methods (1) to (4) described above). The seepage of the adhesive into the cell is effectively prevented. Therefore, it is possible to provide a method for manufacturing an information display panel that can effectively prevent the adhesive applied to the upper surface of the partition wall from leaking into the cell.

  Hereinafter, each member which comprises the information display panel used as the object of this invention is demonstrated.

  Regarding the substrate, at least one of the substrates is a transparent substrate capable of confirming the color of the display medium 3 from the outside of the information display panel, and a material having high visible light transmittance and good heat resistance is preferable. The other substrate may be transparent or opaque. Examples of substrate materials include polymer sheets such as polyethylene terephthalate, polyethersulfone, polyethylene, polycarbonate, polyimide, and acrylic, flexible materials such as metal sheets, and flexible materials such as glass and quartz. There are no inorganic sheets. The thickness of the substrate is preferably from 2 to 5000 μm, more preferably from 5 to 2000 μm. If it is too thin, it will be difficult to maintain the strength and the spacing uniformity between the substrates, and if it is thicker than 5000 μm, it will be a thin information display panel. Is inconvenient.

  Electrode forming materials for the electrodes 5 and 6 provided on the substrate as required include metals such as aluminum, silver, nickel, copper, and gold, and conductive metals such as ITO, indium oxide, conductive tin oxide, and conductive zinc oxide. Examples thereof include conductive polymers such as oxides, polyaniline, polypyrrole, and polythiophene, which are appropriately selected and used. As a method for forming an electrode, a method of forming the above-described materials into a thin film by sputtering, vacuum deposition, CVD (chemical vapor deposition), coating, or the like, or mixing a conductive agent with a solvent or a synthetic resin binder. The method of apply | coating is used. In many cases, the electrode provided on the display surface side substrate needs to be transparent, but the electrode provided on the back surface side substrate does not need to be transparent. In any case, the material that can be patterned and is electrically conductive can be preferably used. Note that the electrode thickness is not particularly limited as long as the conductivity can be secured and the light transmittance is not hindered, and is preferably 3 to 1000 nm, preferably 5 to 400 nm. The material and thickness of the electrode provided on the back side substrate are the same as those of the electrode provided on the display surface side substrate described above, but need not be transparent. In this case, the external voltage input may be superimposed with direct current or alternating current.

  The shape of the partition 4 is optimally set according to the type of display medium involved in the display and is not limited in general. However, the width of the partition is 2 to 100 μm, preferably 3 to 50 μm, and the height of the partition is 10 to 10 μm. The thickness is adjusted to 500 μm, preferably 10 to 200 μm. In forming the partition walls, a both-rib method in which ribs are formed on each of the opposing substrates and then bonded, and a one-rib method in which ribs are formed only on one substrate are conceivable. In the present invention, any method is preferably used.

  As shown in FIG. 5, the display cells formed by the partition walls made up of these ribs are exemplified by a square shape, a triangular shape, a line shape, a circular shape, and a hexagonal shape as viewed from the substrate plane direction. The shape and the mesh shape are exemplified. It is better to make the portion (the area of the frame portion of the display cell) corresponding to the partition wall cross-sectional portion visible from the display side as small as possible, and the clearness of information display increases. Here, examples of the method for forming the partition include a mold transfer method, a screen printing method, a sand blast method, a photolithography method, and an additive method. Among these, a photolithography method using a resist film and a mold transfer method are preferably used.

  Next, the powder fluid used as a display medium in the information display panel of the present invention will be described. As for the name of the powder fluid as the display medium of the present invention, the present applicant has obtained the right of “Electronic Powder Fluid (registered trademark): Registration No. 4636931”.

  The “powder fluid” in the present invention is a substance in an intermediate state of both fluid and particle characteristics that exhibits fluidity by itself without borrowing the force of gas or liquid. For example, liquid crystal is defined as an intermediate phase between a liquid and a solid, and has fluidity that is a characteristic of liquid and anisotropy (optical properties) that is a characteristic of solid (Heibonsha: Encyclopedia) . On the other hand, the definition of particle is an object with a finite mass even if it is negligible, and is said to be affected by gravity (Maruzen: Physics Encyclopedia). Here, even in the case of particles, there are special states of gas-solid fluidized bed and liquid-solid fluids. When gas is flowed from the bottom plate to the particles, upward force is applied to the particles according to the velocity of the gas. Is a gas-solid fluidized bed that is in a state where it can easily flow when it balances with gravity, and it is also called a liquid-solid fluidized state that is fluidized by a fluid (ordinary) Company: Encyclopedia). As described above, the gas-solid fluidized bed body and the liquid-solid fluid are in a state of using a gas or liquid flow. In the present invention, it has been found that a substance in a state of fluidity can be produced specifically without borrowing the force of such gas and liquid, and this is defined as powder fluid.

  That is, the pulverulent fluid in the present invention is in an intermediate state having both the characteristics of particles and liquid, as in the definition of liquid crystal (liquid and solid intermediate phase), and is the characteristic of the above-mentioned particles. It is a substance that is extremely unaffected and exhibits a unique state with high fluidity. Such a substance can be obtained in an aerosol state, that is, in a dispersion system in which a solid or liquid substance is stably suspended as a dispersoid in a gas, and the solid substance is regarded as a dispersoid in the information display panel of the present invention. To do.

The information display panel of the present invention encloses a powder fluid that exhibits high fluidity in an aerosol state in which solid particles are stably suspended as a dispersoid, for example, as a display medium, between opposing substrates, at least one of which is transparent. Such a powder fluid can be easily and stably moved by a Coulomb force or the like by applying a low voltage.
As described above, for example, the powder fluid used as the display medium in the present invention is a substance in the intermediate state between the fluid and particles that exhibits fluidity by itself without borrowing the force of gas or liquid. It is. This powder fluid can be in an aerosol state in particular, and in the information display device of the present invention, a solid substance is used in a state where it floats relatively stably as a dispersoid in the gas.

Next, display medium particles (hereinafter also referred to as particles) constituting the display medium in the information display panel of the present invention will be described. The display medium particles are composed of the display medium particles as they are to form a display medium, or are combined with other particles to form a display medium, or adjusted and configured to become a powder fluid to form a display medium. Or used.
The particles can contain a charge control agent, a colorant, an inorganic additive, and the like, if necessary, in the resin as the main component, as in the conventional case. Examples of resins, charge control agents, colorants, and other additives will be given below.

  Examples of the resin include urethane resin, urea resin, acrylic resin, polyester resin, acrylic urethane resin, acrylic urethane silicone resin, acrylic urethane fluororesin, acrylic fluororesin, silicone resin, acrylic silicone resin, epoxy resin, polystyrene resin, styrene Acrylic resin, polyolefin resin, butyral resin, vinylidene chloride resin, melamine resin, phenol resin, fluororesin, polycarbonate resin, polysulfone resin, polyether resin, polyamide resin and the like can be mentioned, and two or more kinds can be mixed. In particular, acrylic urethane resin, acrylic silicone resin, acrylic fluororesin, acrylic urethane silicone resin, acrylic urethane fluororesin, fluororesin, and silicone resin are suitable from the viewpoint of controlling the adhesive force with the substrate.

  The charge control agent is not particularly limited. Examples of the negative charge control agent include salicylic acid metal complexes, metal-containing azo dyes, metal-containing oil-soluble dyes (including metal ions and metal atoms), and quaternary ammonium salt systems. Examples thereof include compounds, calixarene compounds, boron-containing compounds (benzyl acid boron complexes), and nitroimidazole derivatives. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and the like. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide, ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives and salts thereof, various organic pigments, resins containing fluorine, chlorine, nitrogen, etc. are also charged. It can also be used as a control agent.

  As the colorant, various organic or inorganic pigments and dyes as exemplified below can be used.

Examples of the black colorant include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon and the like.
Examples of blue colorants include C.I. I. Pigment blue 15: 3, C.I. I. Pigment Blue 15, Bituminous Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Metal-free Phthalocyanine Blue, Phthalocyanine Blue Partial Chlorides, Fast Sky Blue, Indanthrene Blue BC, and the like.
Examples of red colorants include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risor red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, Alizarin Lake, Brilliant Carmine 3B, C.I. I. Pigment Red 2 etc.

Yellow colorants include chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, mineral first yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, C.I. I. Pigment Yellow 12 etc.
Examples of green colorants include chrome green, chromium oxide, pigment green B, C.I. I. Pigment Green 7, Malachite Green Lake, Final Yellow Green G, etc.
Examples of the orange colorant include red chrome yellow, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GK, C.I. I. Pigment Orange 31 etc.
Examples of purple colorants include manganese purple, first violet B, and methyl violet lake.
Examples of white colorants include zinc white, titanium oxide, antimony white, and zinc sulfide.

  Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Examples of various dyes such as basic, acidic, disperse, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

Examples of inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, cadmium orange, titanium yellow, Examples include bitumen, ultramarine blue, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, and aluminum powder.
These pigments and inorganic additives can be used alone or in combination. Of these, carbon black is particularly preferable as the black pigment, and titanium oxide is preferable as the white pigment.

  Further, the particles of the present invention preferably have an average particle diameter d (0.5) in the range of 0.1 to 20 μm, and are uniform and uniform. If the average particle diameter d (0.5) is larger than this range, the display is not clear, and if it is smaller than this range, the cohesive force between the particles becomes too large, which hinders the movement of the particles.

Furthermore, in the present invention, regarding the particle size distribution of each particle, the particle size distribution Span represented by the following formula is set to less than 5, preferably less than 3.
Span = (d (0.9) −d (0.1)) / d (0.5)
(However, d (0.5) is a numerical value indicating the particle diameter in μm that 50% of the particles are larger than this, and 50% is smaller than this, and d (0.1) is a particle in which the ratio of the smaller particles is 10%. (Numerical value expressed in μm, and d (0.9) is a numerical value expressed in μm for a particle size of 90% or less.)
By keeping Span within a range of 5 or less, the size of each particle is uniform and uniform particle movement is possible.

  Furthermore, regarding the correlation between the particles, the ratio of d (0.5) of the particles having the minimum diameter to d (0.5) of the particles having the maximum diameter among the used particles is set to 50 or less, preferably 10 or less. It is essential. Even if the particle size distribution Span is reduced, particles with different charging characteristics move in opposite directions, so that the particle size is close to each other and each particle can be easily moved in the opposite direction by the equivalent amount. This is within this range.

The particle size distribution and the particle size can be obtained from a laser diffraction / scattering method or the like. When laser light is irradiated onto particles to be measured, a light intensity distribution pattern of diffracted / scattered light is spatially generated, and this light intensity pattern has a corresponding relationship with the particle diameter, so that the particle diameter and particle diameter distribution can be measured. .
Here, the particle size and particle size distribution in the present invention are obtained from a volume-based distribution. Specifically, using a Mastersizer2000 (Malvern Instruments Ltd.) measuring instrument, particles are introduced into a nitrogen stream, and the attached analysis software (software based on volume-based distribution using Mie theory) The diameter and particle size distribution can be measured.

  The charge amount of the particles used for the display medium naturally depends on the measurement conditions, but the charge amount of the particles used for the display medium in the information display panel is almost the initial charge amount, the contact with the partition, the contact with the substrate, the elapsed time. It was found that the saturation value of the charging behavior of the particles used in the display medium is a governing factor, depending on the charge decay associated with.

  As a result of intensive studies, the present inventors evaluated the range of the appropriate charging characteristic value of the particles used in the display medium by measuring the charge amount of the particles used in the display medium using the same carrier particles in the blow-off method. I found out that I can do it.

Furthermore, in the present invention, when a display medium such as a particle group or a powdered fluid is used for a dry information display panel, it is important to manage the gas in the void surrounding the display medium between the substrates, and display stability is improved. Contribute to. Specifically, it is important that the relative humidity at 25 ° C. is 60% RH or less, preferably 50% RH or less, more preferably 35% RH or less with respect to the humidity of the gas in the gap.
1 to 3, the gap between the opposing substrate 1 and substrate 2 in FIGS. 1 to 3, the occupied portion of the electrodes 5 and 6, the display medium (particle group or powder fluid) 3, and the occupied portion of the partition wall 4. In addition, a gas portion in contact with a so-called display medium excluding a seal portion of the information display panel is meant.
The gas in the gap is not limited as long as it is in the humidity region described above, but dry air, dry nitrogen, dry argon, dry helium, dry carbon dioxide, dry methane, and the like are preferable. This gas needs to be sealed in an information display panel so that the humidity is maintained, for example, filling a display medium, assembling an information display panel, etc. in a predetermined humidity environment, It is important to apply a sealing material and a sealing method that prevent moisture from entering from the outside.

The distance between the substrates in the information display panel of the present invention is not limited as long as the display medium can be moved and the contrast can be maintained, but is usually adjusted to 10 to 500 μm, preferably 10 to 200 μm.
The volume occupation ratio of the display medium in the space between the opposing substrates is preferably 5 to 70%, more preferably 5 to 60%. When it exceeds 70%, the movement of the display medium is hindered, and when it is less than 5%, the contrast tends to be unclear.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples of the present invention, but the present invention is not limited to the following examples.

<Example 1>
The information display panel of the present invention shown in FIG. 2 was manufactured by the following steps (1) to (8). Of the steps, the steps (5), (7), and (8), which are features of the present invention, will be described in detail below, and detailed descriptions of other steps will be omitted.
(1) Partition (rib) and electrode pattern forming process on the substrate (the latter is performed only when an electrode is required)
(2) Step of filling display substrate onto substrate (3) Step of removing unnecessary display medium on partition (4) Step of forming adhesive layer on partition (This adhesive layer forming step is a step of filling the display medium) May be done before)
(5) Fine curing (gelation) process of adhesive layer (6) Overlaying process of alignment (7) Bonding process of two substrates (including main curing process of adhesive)
(8) Inspection process to evaluate the bleeding quality of adhesive

(5) An equal amount of cemedine super (two-part epoxy adhesive) used as an adhesive was transferred to the upper surface of the partition wall of the ribbed substrate to form an adhesive layer, and then allowed to stand at room temperature for 10 minutes for slight curing. I let you. At this time, the solvent insolubility rate was 5.5 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 50 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 2>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) After an equal amount of cemedine super (two-part epoxy adhesive) used as an adhesive was transferred to the upper surface of the ribbed substrate to form an adhesive layer, it was allowed to stand at room temperature for 30 minutes for slight curing. I let you. At this time, the solvent insolubility rate was 31 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 50 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 3>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) After forming WR798 (hybrid adhesive of UV curable adhesive and thermosetting adhesive) used as an adhesive onto the partition wall of the ribbed substrate to form an adhesive layer, high pressure mercury The lamp was slightly cured by irradiating with 2000 mJ / cm ² ) ultraviolet rays. At this time, the solvent insolubility rate was 63 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 120 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 4>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) Ajinomoto Fine Techno Co., Ltd. AE200D (epoxy adhesive using two or more kinds of curing agents) used as an adhesive was transferred to the upper surface of the ribbed substrate to form an adhesive layer, and then heat-circulating oven Was preheated at 90 ° C. for 60 minutes for slight curing. At this time, the solvent insolubility rate was 55 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 120 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 5>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) After transferring W780P-N7 (one-component epoxy adhesive) manufactured by Kyoritsu Chemical Co., Ltd. used as an adhesive to the upper surface of the partition wall of the ribbed substrate, an adhesive layer was formed, and then using a thermal circulation oven, 80 Pre-heating at 60 ° C. for 60 minutes for slight curing. At this time, the solvent insolubility rate was 33 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 120 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 6>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) Ajinomoto Fine Techno Co., Ltd. AE20 (one-part epoxy adhesive) used as an adhesive was transferred to the upper surface of the partition wall of the ribbed substrate to form an adhesive layer, and then heated at 65 ° C. using a thermal circulation oven. It was preheated for 60 minutes to be slightly cured. At this time, the solvent insolubility rate was 45 wt%.
(7) The ribbed substrate was superimposed on the counter substrate and pressed at 80 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Example 7>
As in Example 1, the information display panel of the present invention shown in FIG. 2 was manufactured by the steps (1) to (8).
(5) TB3115 (ultraviolet delayed curable adhesive) manufactured by ThreeBond Co., Ltd. used as an adhesive was transferred to the upper surface of the partition wall of the ribbed substrate to form an adhesive layer, and then ultraviolet rays of 1000 mJ / cm ² with a high-pressure mercury lamp. Was slightly cured by irradiation. At this time, the solvent insolubility rate was 75 wt%.
(7) The ribbed substrate was superimposed on the counter substrate and pressed at 80 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, there was no bleeding as shown in FIG. 4 (a), and the two substrates could be satisfactorily bonded together.

<Comparative Example 1>
As in Example 6, the information display panel shown in FIG. 2 was manufactured by the steps (1) to (8) described above (however, preheating was omitted in the step (5)).
(5) Ajinomoto Fine Techno Co., Ltd. AE20 (one-part epoxy adhesive) used as an adhesive was transferred to the upper surface of the partition wall of the ribbed substrate to form an adhesive layer, and then no preheating was performed. At this time, the solvent insolubility rate was 1 wt%.
(7) The ribbed substrate was superimposed on the counter substrate and pressed at 80 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, the bleeding as shown in FIG. 4 (b) occurred and became defective (NG).

<Comparative example 2>
In the same manner as in Example 1, the information display panel shown in FIG. 2 was manufactured by the steps (1) to (8) described above (however, in the step (5), standing at room temperature was omitted for 10 minutes).
(5) After an equal amount of cemedine super (two-component epoxy adhesive) used as an adhesive was transferred to the upper surface of the partition wall of the ribbed substrate to form an adhesive layer, it was not left at room temperature for 10 minutes. Immediately, the step (7) was carried out. At this time, the solvent insolubility rate was 3 wt%.
(7) The ribbed substrate was superposed on the counter substrate and pressed at 50 ° C. and 0.2 MPa for 60 minutes using a hot press.
(8) After pressing, the state of bleeding of the adhesive was confirmed by microscopic observation. As a result, the bleeding as shown in FIG. 4 (b) occurred and became defective (NG).

  An information display panel and an information display device manufactured by the method of the present invention include display units of mobile devices such as notebook computers, PDAs, mobile phones, and handy terminals, electronic papers such as electronic books and electronic newspapers, signboards, posters, and blackboards. Billboards, calculators, home appliances, car supplies, card displays such as point cards, IC cards, electronic advertisements, electronic POPs, electronic shelf labels, electronic price tags, electronic scores, and display units for RF-ID devices For example, it is suitably used.

It is a figure which shows an example of the information display panel of this invention. It is a figure which shows the other example of the information display panel of this invention. It is a figure which shows the further another example of the information display panel of this invention. It is a figure for demonstrating the test process performed after the bonding process of the board | substrate in the manufacturing method of the information display panel of this invention which evaluates the bleeding quality of an adhesive agent, (a) is the bleeding quality of an adhesive agent. Exemplifies the case of good (OK), and (b) exemplifies the case where the bleeding quality of the adhesive is poor (NG). It is a figure which shows an example of the shape of the partition in the information display panel of this invention.

Explanation of symbols

1, 2 Substrate 3 Display medium (particle group, powder fluid)
3W White display medium 3B Black display medium 4 Bulkhead 5 Electrode 6 Electrode

Claims (5)

A plurality of cells partitioned by partition walls are formed between two opposing substrates, at least one of which is transparent, and at least one type of display medium composed of at least one type of particles is enclosed in the cells. An information display panel manufacturing method for displaying information by moving a display medium by an electric field generated in a substrate,
After the adhesive layer forming process for applying the adhesive on the partition wall upper surface, before the pressing process for bonding the two substrates, the adhesive applied on the partition wall upper surface is slightly cured, A method for producing an information display panel, wherein the applied adhesive is fully cured. As an indicator of slight curing, the solvent insolubility before the pressing step is 5 to 80 wt% (provided that the solvent insolubility (%) = (B / A) × 100, A; the weight of the adhesive before immersion in the solvent; B: Weight after immersion of the adhesive in a good solvent at 25 ° C. for 24 hours)
The method for manufacturing an information display panel according to claim 1.   3. The method for manufacturing an information display panel according to claim 1, wherein the adhesive is various reactive adhesives such as an epoxy adhesive and an acrylic adhesive.   The adhesive is a hybrid adhesive of an ultraviolet curable adhesive and a thermosetting adhesive, an epoxy adhesive using two or more kinds of curing agents having different curing temperatures, a two-component curable epoxy adhesive, and an ultraviolet delayed curable adhesive. 3. The method for manufacturing an information display panel according to claim 1, wherein the information display panel is any one of the above.   An information display device comprising an information display panel manufactured by the manufacturing method according to claim 1.

Images