JP2008051940A - Method for manufacturing information display panel and device for removing display medium used for the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deviation in wear in a specified portion of a roll and a remaining portion of a display medium after removal by carrying out a step of removing the display medium while changing an angular relation between a substrate having barrier walls formed thereon and a roll in every predetermined times. <P>SOLUTION: The step of removing a display medium is included in the manufacturing process of an information display panel that displays information such as an image by applying an electric field to a display medium sealed in cells segmented by barrier walls so as to move the display medium; wherein a roll 14 disposed to be in contact with an upper part of the barrier walls 13, a brush 16 disposed close to the roll to scrape off the display medium 15 transferred to the roll 14, a cleaner 17 disposed close to the brush to remove the display medium 15 scraped by the brush 16, and a stage 18 supporting to rotate the substrate 11 having the barrier walls formed thereon within a predetermined angle range with respect to the roll 14 are used to remove the display medium 15 sticking to the upper part of the barrier walls while changing the angular relation between the substrate 11 having the barrier walls formed thereon and the roll 14 in every predetermined times. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  According to the present invention, a plurality of cells partitioned by a partition wall are formed between two opposing substrates, at least one of which is transparent, and a display medium having optical reflectance and chargeability is enclosed in the cells, As a manufacturing process of an information display panel for displaying information such as an image by moving the display medium by applying an electric field to the medium, at least a display medium filling process for filling the cells in the cell and an excess display medium The present invention relates to a method for manufacturing an information display panel having a display medium removing process for removing the display medium, and a display medium removing apparatus used therefor.

  As an information display device that replaces a liquid crystal display device (LCD), a plurality of cells partitioned by partition walls are formed between two opposing substrates, at least one of which is transparent, and optical reflectivity and chargeability are formed in the cells. There is known a dry information display panel that encloses a display medium having a liquid crystal display and applies an electric field to the display medium to move the display medium to display information such as an image. When the substrate with partition walls constituting this information display panel is manufactured, for example, as shown in the plan view of FIG. 6B, a plurality of locations (six locations in the illustrated example) on the upper surface of the glass substrate 51 for multi-face drawing. ) To form a panel display region for a plurality of (six in the illustrated example) substrates 52 with grid-like partitions, and the same height as the above-mentioned partitions around the four sides of the substrate 52 with grid-like partitions. Dummy solid partition walls 53 and 54 are formed, and the display medium 55 (see FIG. 6A) is filled into a plurality of cells partitioned by the partition walls on the substrate.

In the above information display panel, if the display medium placed on the upper part of the partition wall forming the cell is left without being removed as it is, the display medium placed on the upper part of the partition wall can be uniformly in-plane when the two substrates are overlaid. There is a possibility that display cannot be performed and display failure may occur.
As a countermeasure, the applicant of the present application first scrapes off the roll 56 for transferring the display medium 55 placed on the upper part of the partition and the display medium 55 transferred to the roll 56 as shown in FIG. A method and apparatus (display medium removing apparatus) for removing the display medium on the upper part of the partition wall using the brush 57 and the cleaner 58 for removing the display medium 55 scraped off by the brush 57 have been proposed. . Further, the applicant of the present application previously has a roll having an axial length that is equal to or greater than the length in a direction perpendicular to the transport direction of the substrate on which the partition is formed, and is disposed so as to be in contact with the upper portion of the partition. In order to continuously remove the particles or powder fluid transferred to the surface, a device (a display medium removing device; see Patent Document 1) that has been arranged at a portion that does not contact the upper part of the partition wall has been proposed. .
JP-A-2005-250142

  Since the display medium removing apparatus employs a mechanism that linearly moves the substrate back and forth in the substrate transport direction, when the display medium removing process of the substrate having the partition pattern shown in FIG. The specific part of the roll located on the upper part of the dummy solid partition wall 53 whose position is determined depending on the partition pattern of the substrate 52 with the lattice-like partition wall is worn away, and thereafter, the part of the dummy solid partition wall 53 in FIG. When the display medium removal process of the glass substrate on which the substrate with lattice-like partition walls is formed is performed, a streak-shaped display medium removal residue corresponding to the dummy solid partition walls 53 is generated. As a result, in the information display panel configured using the substrate on which the display medium removal residue has occurred, when the two substrates are overlapped by the display medium remaining on the upper part of the partition wall, it cannot be bonded in-plane uniformly. The durability of the information display panel is reduced due to poor contact, and the display failure of the information display panel is caused by streaky display unevenness.

  The present invention prevents the uneven wear of a specific part of the roll by performing the display medium removing process while changing the angular relationship between the roll and the substrate on which the partition wall is formed every predetermined number of times, resulting in a decrease in durability and display failure. It is an object of the present invention to provide a method for manufacturing an information display panel that does not cause the problem.

  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 optically forming the cells. As a manufacturing process of an information display panel for displaying information such as an image by enclosing a display medium having a static reflectivity and chargeability and applying an electric field to the display medium to display information such as an image, at least the display medium is used. An information display panel manufacturing method comprising a display medium filling step for filling a cell and a display medium removal step for removing excess display medium, wherein the display medium removal step is in contact with an upper portion of the partition wall. A roll arranged on the roll, a brush arranged near the roll to scrape the display medium transferred to the roll, and a display medium scraped off by the brush. A substrate having the partition walls formed every predetermined number of times using a cleaner disposed in the vicinity of the brush and a stage that supports the substrate on which the partition walls are formed so as to be able to rotate within a predetermined angle range with respect to the roll. It is a display medium removal step of removing the display medium attached to the upper part of the partition wall while changing the angular relationship between the roll and the roll.

  As a preferred example of the method for producing an information display panel according to the present invention, the axial length of the roll is equal to or longer than the diagonal length of the substrate for multi-sided the substrate on which the partition is formed. .

  The display medium removing apparatus used in the method for manufacturing an information display panel of the present invention includes a roll disposed so as to be in contact with an upper part of a partition formed on a substrate, and a display medium transferred to the roll is scraped off. Therefore, a brush disposed near the roll, a cleaner disposed near the brush to remove the display medium scraped off by the brush, and a substrate on which the partition wall is formed within a predetermined angle range with respect to the roll. A display medium removing apparatus including a stage that is supported so as to be rotatable is preferable.

  According to the method for manufacturing an information display panel of the present invention having the above-described structure, a plurality of cells partitioned by a partition are formed between two opposing substrates, at least one of which is transparent, and optical reflection is performed in the cells. As a manufacturing process of an information display panel for displaying information such as an image by enclosing a display medium having a rate and chargeability and applying an electric field to the display medium, at least the display medium is the cell. A roll arranged so that the display medium removal step in the method for manufacturing an information display panel having a display medium filling step for filling in and a display medium removal step for removing excess display medium is in contact with the upper part of the partition wall A brush disposed near the roll to scrape off the display medium transferred to the roll, and a brush to remove the display medium scraped off by the brush Using a cleaner disposed near the substrate, and a stage that supports the substrate on which the partition is formed so that the substrate can be rotated within a predetermined angle range with respect to the roll, and the substrate on which the partition is formed every predetermined number of times, and Since the display medium removal process is to remove the display medium attached to the upper part of the partition while changing the angular relationship with the roll, when the display medium removal process of the substrate having a certain partition pattern is continuously repeated many times. Since the part of the roll 14 in contact with the dummy solid partition wall is averaged without being biased to the specific part by the change of the angular relationship every predetermined number of times by the stage 18, the partial wear of the specific part of the roll does not occur. The display medium removal residue does not occur. Therefore, it is possible to provide a method for manufacturing an information display panel that does not cause deterioration in durability or display failure.

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

  First, a basic configuration of an information display panel manufactured by the manufacturing method of the present invention will be described. In the information display panel manufactured by the manufacturing method of the present invention, an electric field is applied to a display medium sealed between two opposing substrates. Along with the applied electric field direction, the display medium is attracted by the force of the electric field, the Coulomb force, or the like, and the display medium changes the moving direction by the change of the electric field direction, thereby displaying information such as an image. Therefore, it is necessary to design the information display panel so that the display medium can move uniformly and maintain the stability when the display information is rewritten or when the display information is continuously displayed. Here, as the force applied to the particles constituting the display medium, in addition to the force attracting each other by the Coulomb force between the particles, an electric mirror image force between the electrode and the substrate, an intermolecular force, a liquid cross-linking force, gravity and the like can be considered.

  An example of an information display panel manufactured by the manufacturing method of the present invention will be described with reference to FIGS.

  In the example shown in FIG. 1, at least two or more types of display media 3 (here, white display media consisting of particles of display white particles 3Wa) having different optical reflectivity and charging characteristics composed of at least one type of particles. 3W and a black display medium 3B composed of a group of black particles 3Ba for display) are moved vertically to the substrates 1 and 2 in accordance with the electric field applied from the outside of the substrates 1 and 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. 1, for example, a partition wall 4 is provided between the substrates 1 and 2 in a lattice shape to form a cell. Moreover, in FIG. 1, the partition in front is abbreviate | omitted.

  In the example shown in FIG. 2, at least two or more types of display medium 3 (here, a white display medium composed of a group of white particles for display 3 </ b> Wa) having different optical reflectivity and charging characteristics composed of at least one type of particles. 3W and a black display medium 3B composed of a group of black particles 3Ba for display) is applied to an 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. Accordingly, the black display medium 3B is moved vertically to the substrates 1 and 2 and the black display medium 3B is visually recognized by the observer, or black display is performed, or the white display medium 3W is visually recognized by the observer and white display is performed. Yes. 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 cell. Moreover, in FIG. 2, the partition in front is abbreviate | omitted.

In the example shown in FIG. 3, one type of display medium 3 having optical reflectivity and chargeability composed of at least one type of particles (here, a white display medium 3W composed of a group of white particles 3Wa for display is used). The white display medium is moved in a direction perpendicular to the substrates 1 and 2 in accordance with an 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. 3W is visually recognized by the observer and white display is performed, or the color of the electrode 6 or the substrate 1 is visually recognized by the observer and the color of the electrode 6 or the substrate 1 is displayed. 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 cell. Further, in FIG. 3, the front partition is omitted.
2 and 3, the electrode may be provided outside the substrate, inside the substrate, or embedded in the substrate.

  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. The powder fluid will be described later.

  Hereafter, the manufacturing method of the information display panel of this invention is demonstrated in detail. 4A and 4B are a cross-sectional view and a plan view, respectively, showing the configuration of an example of a display medium removing apparatus used in the display medium removing step of the method for manufacturing an information display panel of the present invention. The display medium removing device (cleaning device) used in the method of the present invention is different from the display medium removing device shown in FIGS. 6A and 6B in that the substrate on which the partition is formed rotates within a predetermined angle range with respect to the roll. The stage which supports so as to obtain is added. That is, the display medium removing device (cleaning device) used in the method of the present invention is a multi-sided substrate (for example, a glass substrate) 11 as shown in the sectional view of FIG. 6A and the plan view of FIG. The roll 14 disposed so as to be in contact with the upper part of the partition wall 13 of the substrate 12 with grid-like partition walls formed at a plurality of locations (six locations in the illustrated example) on the upper surface, and the display medium 15 transferred to the roll 14 are scraped off. Therefore, a brush 16 disposed in the vicinity of the roll 14, a cleaner 17 disposed in the vicinity of the brush 16 for removing the display medium 15 scraped by the brush 16, and a substrate 12 with a lattice-like partition wall are formed. And a stage 18 that supports the multi-sided substrate 11 so as to be able to rotate with respect to the roll 14 within a predetermined angle range (within the angle range indicated by the arrow A in FIG. 4B). Dummy solid partition walls 19 and 20 having the same height are formed on the four sides around the substrate 12 with grid-like partitions formed on the multi-planar substrate 11, and a plurality of partitions separated by the partitions on the substrate with grid-like partitions are provided. A display medium 15 (white display medium 15W and black display medium 15B in the illustrated example) is filled in the cell. FIG. 6B shows a state where the brush and the cleaner are removed for convenience of explanation.

As the roll 14, a conductive roll having an axial length equal to or longer than the diagonal length of the multi-sided substrate 11 on which the substrate 12 with grid-like partition walls is formed is used. The roll 14 has a roll surface covered with an elastic body, and the elastic body has an elastic modulus smaller than the elastic modulus of the partition wall 4 (or a surface hardness softer than the surface hardness of the partition wall 13) and 1 × 10 ⁹ (Ω). / □) It has the following surface resistivity and a surface roughness equal to or less than the average particle diameter (for example, 5 μm) of the particles constituting the display medium.
As the brush 16, a hair brush or sponge brush, which is a rotating roll brush, is used to obtain a desired particle scraping function. The rotation of the brush 16 may be independently rotated with respect to the contacting roll 11 or may be dependently rotated with respect to the contacting roll 14. Further, the brush 16 may rotate in the same direction with respect to the roll 14 in contact, or may rotate in the opposite direction. The number of the brushes 16 may be one or plural, and can be optimally designed for efficiently removing particles transferred and adhered to the roll 14.
As the cleaner 17, for example, a line nozzle (not shown) arranged so as to extend in the width direction orthogonal to the substrate transport direction, and a suction part (see FIG. (Not shown).

  As the stage 18, a stage that supports the multi-sided substrate 11 so as to be able to rotate with respect to the roll 14 within an angle range of an arrow A in FIG. 4B is used. A stage that supports the unit including the brush 16 and the cleaner 17 so that the unit can be rotated within the angle range of the arrow A in FIG.

Next, the manufacturing method of the information display panel of this invention is demonstrated.
First, a plurality of cells partitioned by partitions 13 on a plurality of (six in the illustrated example) substrate 12 with grid-shaped partitions formed at a plurality of locations (six in the illustrated example) on the upper surface of the multi-planar substrate 11. The multi-chamfer substrate 11 filled with the display medium 15 is transported to the display medium removal step and placed on the stage 18. Next, by operating the stage 18, the multi-chamfer substrate 11 is rotated with respect to the roll 14 within the angle range indicated by the arrow A in FIG. 4B, for example, to have the angular relationship shown in FIG. Thereafter, by operating the roll 14, the brush 16, and the cleaner 17, a display medium removal process for removing the display medium 15 attached to the upper part of the partition wall 13 is performed. This display medium removing process is performed in a reciprocating process by moving the roll 14 back and forth with respect to one multi-planar substrate 11, and the stage 18 is operated every predetermined number of times for multi-planar processing. Assume that the angle relationship between the substrate 11 and the roll 14 is changed. This change in angular relationship is achieved, for example, by changing the angular relationship by 15 ° in the clockwise direction every time a roll is reciprocated on one substrate, and removing the display medium from one substrate by reciprocating the roll 10 times. After the process is finished, for the next substrate, the stage is again brought into a state where the short side direction of the substrate, which is the origin, and the roll long side direction coincide with each other, and then the display medium removal step similar to that for the single substrate is performed do it.

According to the method for manufacturing an information display panel of the present invention, when the display medium removing step of the multi-sided substrate 11 on which the substrate 12 with grid-like partitions having a certain partition pattern is formed is continuously repeated many times, By changing the angular relationship for each predetermined number of sheets by the stage 18, the part of the roll 14 that contacts the dummy solid bulkheads 19, 20 is averaged without being biased toward the specific part. No display medium removal residue occurs. Therefore, it is possible to provide a method for manufacturing an information display panel that does not cause deterioration in durability or display failure.
Furthermore, the display medium on the partition wall 13 can be efficiently produced in a short time by manufacturing the information display panel while removing the display medium 15 adhering to the upper part of the partition wall 13 using the method for manufacturing the information display panel of the present invention. 15 can be removed, the adhesion failure between the two substrates due to the remaining display medium above the partition walls is drastically reduced, and an information display panel with stable quality can be manufactured.

  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 on which the color of the display medium can be confirmed from the outside of the panel, and a material having high visible light transmittance and good heat resistance is preferable. The back substrate as the other substrate may be transparent or opaque. Examples of substrate materials include polymer sheets such as polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyethylene, polycarbonate, polyimide, and acrylic, flexible materials such as metal sheets, and glass and quartz. An inorganic sheet having no flexibility is mentioned. 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 electrodes provided on the substrate as required include metals such as aluminum, silver, nickel, copper, gold, indium tin oxide (ITO), indium oxide, antimony tin oxide (ATO), conductive oxidation Examples include conductive metal oxides such as tin and conductive zinc oxide, and conductive polymers such as polyaniline, polypyrrole, and polythiophene, which are appropriately selected and used. The electrode can be formed by patterning the above-described materials into a thin film by sputtering, vacuum deposition, CVD (chemical vapor deposition), coating, or the like, or by mixing a conductive agent with a solvent or synthetic resin binder. A method of applying and patterning is used. The electrode provided on the viewing side (display surface side) substrate needs to be transparent, but the electrode provided on the back side substrate does not need to be transparent. In any case, the above-mentioned material that is conductive and capable of pattern formation can be suitably 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 walls 4 provided on the substrate is optimally set as appropriate depending on the type of display medium involved in display, the shape and arrangement of electrodes to be arranged, and is not limited in general, but the width of the partition walls is 2 to 100 μm, preferably The height of the partition wall is adjusted to 10 to 100 μm, preferably 10 to 50 μm, to 3 to 50 μm.
In forming the partition wall, a both-rib method in which ribs are formed on each of the opposing substrates 1 and 2 and then bonded, and a single-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 cells formed by the partition walls made 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 plane of the substrate. And a mesh shape. It is better to make the portion corresponding to the cross section of the partition wall visible from the display surface side (the area of the cell frame) as small as possible, and the display becomes clearer.
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. Any of these methods can be suitably used for the information display panel of the present invention, and among these, a photolithography method using a resist film and a mold transfer method are suitably used.

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

  The “powder fluid” used as a display medium in the present invention is a substance in an intermediate state between fluid and particles 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 used as the display medium in the present invention is an intermediate state having both particle and liquid characteristics, similar to the definition of liquid crystal (intermediate phase between liquid and solid). It is a substance that is extremely resistant to the effects of gravity and that exhibits a unique state of 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 a solid substance is used as a dispersoid in an information display panel. is there.

The information display panel to which the present invention is applied encloses a powder fluid that exhibits high fluidity in an aerosol state in which at least one is transparent, between opposed substrates, for example, solid particles in gas are stably suspended as a dispersoid Such a pulverulent fluid is so fluid that it does not have an angle of repose, which is an index indicating the fluidity of the powder, and is easily stabilized by Coulomb force with a small electric field force. Can be moved.
As described above, the powdered fluid is a substance in an intermediate state between the fluid and the particle, which exhibits fluidity by itself without borrowing the force of gas or liquid. This powder fluid can be in an aerosol state in particular, and in the information display panel that is the subject of the present invention, a solid substance is used as a display medium in a state where it floats relatively stably as a dispersoid in the gas. .

A method for charging the colored particles for display negatively or positively is not particularly limited, and a method for charging particles such as a corona discharge method, an electrode injection method, and a friction method is used. It is preferable that the charge amount of particles measured by a blow-off method using a carrier is 10 to 100 μC / g in absolute value. When the absolute value of the charge amount is lower than this range, the response speed with respect to the change in the electric field is slowed, and the memory property is also lowered. If the absolute value of the charge amount is higher than this range, the image force on the electrode or the substrate is too strong, and the memory property is good, but the reversal followability of the display medium when the electric field is reversed becomes poor.
In the present invention, the charge amount was measured as follows.
<Blow-off measurement principle and measurement method>
In the blow-off method, a mixture of colored particles for display and a carrier is put into a cylindrical container with nets at both ends, and high-pressure gas is blown from one end to separate the colored particles for display and carriers from the mesh opening. Blow off only the colored particles for display. At this time, the charge amount equivalent to the charge amount of the colored particles for display taken away from the container remains in the carrier. All of the electric flux due to this charge is collected by the Faraday cage, and the capacitor is charged by this amount. Therefore, by measuring the potential across the capacitor, the charge amount Q of the colored particles for display is
Q = CV (C: capacitor capacity, V: voltage across the capacitor)
As required.
As a blow-off charge amount measuring device, TB-200 manufactured by Toshiba Chemical Corporation was used. In the present invention, a ferrite carrier is used to measure the charge amount of the particles to be measured. The information display panel is composed of, for example, a display medium composed of positively charged colored particles for display and negatively charged colored particles for display. When two types of display media are used in combination with the display medium to be used, the same type of carrier is used when measuring the charge amount of the display colored particles constituting each display medium. Specifically, the charge amount (μC / g) of the particles was measured using a DFC100 wrinkle (Mn—Mg-containing ferrite system) manufactured by Dowa Iron Powder Industry Co., Ltd. as a carrier.

Since the particles need to retain their charged charges, insulating particles having a volume resistivity of 1 × 10 ¹⁰ Ω · cm or more are preferable, and in particular, insulating particles having a volume resistivity of 1 × 10 ¹² Ω · cm or more. Is preferred. Further, particles having a slow charge decay property are more preferable.

Next, display colored particles (hereinafter also referred to as particles) constituting the display medium in the information display panel which is the subject of the present invention will be described. The colored particles for display have optical reflectivity (color) and chargeability, and are composed of the colored particles for display as they are, or are combined with other particles to form a display medium. Or adjusted and configured so as to be a powdered fluid to be used as a display medium.
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 addition, a resin polymerized in advance may be used, or a resin may be polymerized at the time of particle formation. Furthermore, it is good also as a copolymer using several types of resin raw materials at the time of superposition | polymerization. In particular, an acrylic resin, an acrylic fluororesin, a polystyrene resin, and a styrene acrylic resin are suitable from the viewpoint of controlling the adhesive force with the substrate and the ease of suspension polymerization.

  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), nitroimidazole derivatives, and styrene acrylic resins having negatively charged functional groups. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and styrene acrylic resins having positively charged functional groups. 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, resol 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. By blending the colorant, colored particles for display having a desired color can be produced.

  Further, the colored particles for display (hereinafter, also referred to as particles) used in the present invention have an average particle diameter d (0.5) in the range of 1 to 20 μm and are preferably 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 display medium.

Furthermore, in the present invention, regarding the particle size distribution of each particle, the particle size distribution Span represented by the following formula is 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 expressing 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 diameter of 90% or less.)
By keeping Span within a range of 5 or less, the size of each particle is uniform, and movement as a uniform display medium becomes 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.

Furthermore, in the information display panel manufactured in the air space manufactured by the manufacturing method of the present invention, it is important to manage the gas in the gap surrounding the display medium between the substrates, which contributes to improvement in display stability. Specifically, it is important that the relative humidity at 25 ° C. is 60% RH or less, and preferably 50% RH or less for the humidity of the gas in the gap.
1 to 3, electrodes 5 and 6 (when electrodes are provided inside the substrate), a portion occupied by the display medium 3, and a partition wall from a portion sandwiched between the opposing substrate 1 and substrate 2 in FIGS. The gas portion in contact with the so-called display medium excluding the occupied portion 4 and the seal portion of the information display panel is indicated.
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 that is the subject 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%. If it exceeds 70%, the movement of the display medium is hindered, and if it is less than 5%, the contrast tends to be unclear.

The information display panel produced by the manufacturing method of the present invention is a notebook computer, an electronic notebook, a portable information device called PDA (Personal Digital Assistants), a display unit of a mobile device such as a mobile phone or a handy terminal, an electronic book, an electronic Electronic paper such as newspapers, signboards, posters, bulletin boards such as blackboards and whiteboards, electronic desk calculators, display units for home appliances, automobile supplies, card display units such as point cards and IC cards, electronic advertisements, information boards, electronic Suitable for POP (Point Of Presence, Point Of Purchase advertising), electronic price tag, electronic shelf label, electronic score, display part of RF-ID equipment, as well as display part of various electronic equipment such as POS terminal, car navigation device, clock, etc. Used for.
The information display panel driving method according to the present invention includes a simple matrix driving display panel, a static driving display panel that does not use a switching element in the panel itself, and three thin film transistors (TFTs). Various types of information display panels such as an active matrix drive type display panel using a two-terminal switching element represented by a terminal switching element or a thin film diode (TFD) can be used.

It is a figure which shows an example of the information display panel used as the object of this invention. It is a figure which shows the other example of the information display panel used as the object of this invention. It is a figure which shows the further another example of the information display panel used as the object of this invention. (A), (b) is sectional drawing and a top view which show the structure of an example of the display medium removal apparatus used for the display medium removal process of the manufacturing method of the information display panel of this invention. It is a figure which shows an example of the shape of the partition in the information display panel used as the object of this invention. (A), (b) is sectional drawing and a top view which show the structure of an example of the display medium removal apparatus used for the display medium removal process of the manufacturing method of the information display panel of a prior art example.

Explanation of symbols

1, 2 Substrate 3 Display medium (particle group, powder fluid)
3W White display medium 3B Black display medium 3Wa White particles for display 3Ba Black particles for display 4 Bulkhead 5 Electrode 6 Electrode 11 Multi-sided substrate 12 Substrate with latticed partition wall 13 Bulkhead 14 Roll 15, 15B, 15W Display medium 16 Brush 17 Cleaner 18 Stage 19, 20 Dummy solid bulkhead 19, 20

Claims (3)

A plurality of cells partitioned by a partition are formed between two opposing substrates, at least one of which is transparent, a display medium having optical reflectivity and chargeability is enclosed in the cell, and an electric field is applied to the display medium. As a manufacturing process of an information display panel that displays information such as images by moving the display medium by applying, a display medium filling process for filling at least the display medium in the cell and a display for removing excess display medium A method of manufacturing an information display panel having a medium removal step,
In the display medium removing step, the roll disposed so as to be in contact with the upper portion of the partition wall, the brush disposed in the vicinity of the roll for scraping the display medium transferred to the roll, and the brush scraped off by the brush. Using a cleaner disposed in the vicinity of the brush for removing the display medium and a stage for supporting the substrate on which the partition is formed so as to be able to rotate within a predetermined angle range with respect to the roll, every predetermined number of times. A method of manufacturing an information display panel, comprising: a display medium removing step of removing a display medium attached to an upper portion of the partition wall while changing an angular relationship between the substrate on which the partition wall is formed and the roll.   2. The method for manufacturing an information display panel according to claim 1, wherein the length of the roll in the axial direction is equal to or longer than the diagonal length of the substrate for taking a multi-sided substrate on which the partition walls are formed.   A roll disposed so as to be in contact with an upper portion of a partition formed on the substrate, a brush disposed near the roll to scrape the display medium transferred to the roll, and a display medium scraped by the brush. A cleaner disposed near the brush for removal, and a stage for supporting the substrate on which the partition is formed so as to be able to rotate within a predetermined angle range with respect to the roll, A display medium removing apparatus used in the method for manufacturing an information display panel according to claim 1.

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