JPWO2011077668A1 - Information display panel and manufacturing method thereof - Google Patents

Abstract

The present invention can display not only rewritable information displayed on a display medium but also fixed information as a background of the rewritable display information at the same time in the same information display screen area. It aims at providing a panel and its manufacturing method. An information display panel according to the present invention includes an observation side substrate that is at least partially transparent, a back side substrate that is at least opposite to the transparent part of the observation side substrate, the observation side substrate, and the back side substrate. In an information display panel that has a transparent partition that secures a distance between and a display medium that is disposed between the substrates and can be driven by an electric field, and rewrites display information by driving the display medium with an electric field, An image serving as a background of the display information is formed on a surface of the back side substrate opposite to the observation side substrate.

Description

  The present invention provides an observation-side substrate that is at least partially transparent, a back-side substrate that is transparent to at least a transparent portion of the observation-side substrate, and a space between the observation-side substrate and the back-side substrate. The present invention relates to an information display panel having a transparent partition wall for partitioning a cell and a display medium disposed in the cell and capable of being driven by an electric field, and rewriting display information by driving the display medium with an electric field.

  In a conventional information display panel, a partition is formed on one of two panel substrates, and after filling a display medium in a cell space formed by surrounding the partition, the other panel substrate on which the partition is not formed is mounted. The information display panel is formed by bonding with an adhesive disposed on the upper surface of the partition wall. Alternatively, a partition is formed on both of the two panel substrates, and a cell formed by surrounding the partition is filled with a display medium. An information display panel is formed by pasting together with an agent.

  Japanese Laid-Open Patent Publication No. 2002-139748 discloses an information display panel provided with a rib-shaped light shielding member called a black matrix (BM), in which partition walls are arranged in a lattice pattern in order to arrange square cells in a matrix, and a partition wall An information display panel colored in its entirety is disclosed. As shown in FIG. 10, this is known as an information display panel in which a black matrix is formed by arranging a rib-shaped black light shielding material on the upper surface of partition walls provided in a grid pattern to form cells. Yes. As an example other than black, a white matrix using a white light-shielding material is known, but a configuration in which rib-shaped light-shielding materials are similarly arranged in a grid pattern for other colors is also known.

As described above, conventionally, a colored member is arranged in a grid shape on the entire upper surface of the partition wall formed in a lattice shape on the entire display screen, or an entire upper surface of the partition wall formed in the entire display screen is colored and arranged. An information display panel having a configuration to perform is known.
However, these colored members are arranged uniformly on the entire display screen so that the image (information) displayed on the screen can be seen clearly, and the information that can be displayed on the screen is There is a problem that information can be displayed only by an image obtained by driving a display medium arranged in a cell between panel substrates.

  Accordingly, an object of the present invention is not only to display information displayed on the display medium in the cell, but also to other information on the area occupied by the partition walls for cell formation, which is originally a non-display area, in order to solve the above-described problems. Display panel capable of simultaneously displaying the rewritable display information and the non-rewritable fixed information serving as a background image of the rewritable display information in the same information display screen area and its manufacture Is to provide a method.

  An information display panel according to the present invention includes an observation side substrate that is at least partially transparent, a back side substrate that is transparent to at least a transparent part of the observation side substrate, the observation side substrate, and the back side substrate. In an information display panel that includes a transparent partition wall that secures a distance between and a display medium that is disposed between the substrates and that can be driven by an electric field, and that rewrites display information by driving the display medium with an electric field, An image serving as a background of the display information is formed on a transparent portion of the back side substrate on a surface opposite to the observation side substrate.

In the information display panel of the present invention, the optical reflectance of the background image is different from the optical reflectance of the display medium.
Here, the “optical reflectance” is different, for example, when the display medium is composed of a white particle group and a black particle group, the background image formed on the back side substrate is white. And a color other than black. Furthermore, when the background image is formed in a lighter color tone than black, it means that the display information on the display medium and the background image can be visually recognized to the extent that they can be distinguished.

  In the information display panel of the present invention, the display medium is composed of a white particle group and a black particle group having different charging polarities, and the background image is other than white and black, and is more black than black. It is characterized by being formed with light colors.

  In the information display panel according to the present invention, a stripe electrode is provided as a transparent conductive film on the observation side substrate, and a stripe electrode is provided as a transparent conductive film on the back side substrate, and the stripe electrodes are formed so as to intersect with each other. The counter electrode pairs are arranged in a matrix.

  In the information display panel of the present invention, a common electrode as a transparent conductive film is provided on the observation side substrate, a pixel electrode with a thin film transistor (TFT) is provided as a conductive film on the back side substrate, and the common electrode and the pixel electrode are provided. The counter electrode pairs formed to be opposed to each other are arranged in a matrix, and transparent partition walls are arranged between the adjacent pixel electrodes with thin film transistors (TFTs).

  Furthermore, the present invention is characterized in that, in the method for manufacturing an information display panel as described above, an image as a background of the display information is formed on the surface of the rear substrate.

According to the present invention, not only display information that can be rewritten by movement of a display medium disposed in a cell in a space between the observation side substrate and the back side substrate, but also information display screen area of the observation side substrate can be handled. The fixed image formed on the surface in the area corresponding to the information display screen area on the outer side surface after making the area of the back side substrate transparently configured through the transparent partition forming the cell As an image serving as a background of the rewritable display information, it can be simultaneously displayed in the same information display screen area.
Thereby, even if the display information is rewritten by driving the display medium, the fixed image formed on the transparent surface of the back-side substrate corresponding to the information display screen area outside the panel is steadily viewed. It is possible to provide an information display panel that can be used.

(A), (b) is the information display panel which can apply this invention, Comprising: It is a figure for demonstrating the structure in the case of the dot matrix display system by passive drive. (A), (b) is the information display panel which can apply this invention, Comprising: It is a figure for demonstrating the structure in the case of the dot matrix display system by active drive. (A), (b) is an information display panel to which the present invention can be applied, and is a diagram for explaining a configuration in the case of a dot matrix display system in which particles in a microcapsule are moved by active driving. It is. (A), (b) is an information display panel to which the present invention can be applied, and is a diagram showing an example of display rewriting using an external electric field forming means. (A), (b) is an information display panel to which the present invention can be applied, and is a diagram showing an example of display rewriting using an external electric field forming means. (A)-(d-ii) is a figure which shows an example of the formation process of the fixed image used as a background attached on the back side board | substrate used as the panel outer side of the information display panel by this invention, respectively (e) , (F) respectively show the display state in each process step visually recognized by the observer. (A)-(d-ii) is a figure which shows an example of the formation process of the fixed image used as a background attached on the back side board | substrate used as the panel outer side of the information display panel by this invention, respectively (e) , (F) respectively show the display state in each process step visually recognized by the observer. It is a figure which shows the structure of the information display panel by this invention, (a) shows the example of a passive drive dot matrix display panel, (b) has shown the example of the active drive dot matrix display panel. It is a figure which shows the example of a display of the information display panel by this invention produced based on the formation process of FIG.6 and FIG.7. It is a figure which shows an example of the conventional information display panel.

  First, the configuration of the information display panel that is the subject of the present invention will be described. In the information display panel which is an object 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 an electric field force or a Coulomb force, and the display medium is moved by a change in the electric field direction, whereby information such as an image is displayed. 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. For example, the display medium is configured as a particle group including a chargeable particle. 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.

  A basic configuration of an information display panel to be an object of the present invention and an example of forming display information using a display medium composed of particle groups are shown in FIGS. , (B) will be described.

  In the example shown in FIGS. 1 (a) and 1 (b), at least two types of display media having different optical reflectivity and charging characteristics (here, they are configured as a particle group including particles having optical reflectivity and chargeability (here, A white display medium 3W configured as a particle group including negatively charged white particles 3Wa and a black display medium 3B configured as a particle group including positively charged black particles 3Ba) are formed of transparent partition walls 4. In each cell, the substrate 1 corresponds to the electric field generated by applying a voltage to the pixel electrode pair formed by the stripe electrode 6 provided on the substrate 2 and the stripe electrode 5 provided on the substrate 1 crossing each other at right angles. 2, a configuration of a passive drive system that is moved substantially perpendicular to 2 is adopted. Then, the white display medium 3W is visually recognized by the observer as shown in FIG. 1A, or the black display medium 3B is visually recognized by the observer as shown in FIG. 1B. Are displayed in a matrix with black and white dots. In addition, in FIG. 1 (a), (b), the partition in front is abbreviate | omitted. Further, here, the pixels and the cells are made to correspond one-to-one, but they may correspond to two-to-one, three-to-one, four-to-one, and the like. Moreover, it is not necessary to make a pixel and a cell correspond. Furthermore, the color of the display medium is not necessarily limited to black and white, and any combination of colors may be used as long as they are different from each other.

In the example shown in FIGS. 2A and 2B, at least two types of display media having different optical reflectivity and charging characteristics (here, the particle group including particles having optical reflectivity and chargeability) A white display medium 3W configured as a particle group including negatively charged white particles 3Wa and a black display medium 3B configured as a particle group including positively charged black particles 3Ba) are formed of transparent partition walls 4. In each cell, an electric field generated by applying a voltage to a pixel electrode pair formed by the electrode 5 (pixel electrode with TFT) provided on the substrate 1 and the electrode 6 (common electrode) provided on the substrate 2 facing each other. Accordingly, the active drive system is configured to move substantially perpendicularly to the substrates 1 and 2. Then, the white display medium 3W is visually recognized by the observer as shown in FIG. 2A, or the white display is displayed by the observer, or the black display medium 3B is visually recognized by the observer as shown in FIG. 2B. Are displayed in a matrix with black and white dots. In addition, in FIG. 2 (a), (b), the partition in front is abbreviate | omitted. Further, here, the pixels and the cells are made to correspond one-to-one. Furthermore, the colors of the white display medium 3W and the black display medium 3B are not necessarily limited to black and white, and any combination of colors may be used as long as they are different from each other.

  Further, as in the example shown in FIGS. 3A and 3B, a microcapsule in which particles having different optical reflectivity and charged polarity, which are composed of two kinds of chargeable particles, together with a transparent insulating liquid are sealed. Is placed in a cell in the space between the common electrode substrate on the observation side and the TFT substrate on the back side, and the electric field generated by the voltage applied to the counter electrode pair in units of pixels formed by the counter electrode pair Dot matrix display is performed by active driving to move the particles in the capsule. In the example of FIGS. 3A and 3B, nine pixel electrode pairs are formed in a region surrounded by the transparent partition wall 4, and one microcapsule is disposed in each pixel electrode pair. The number of pixel electrode pairs may not correspond to the number of microcapsules. One pixel electrode pair is formed in a region surrounded by the transparent partition walls 4 and one microcapsule is arranged in each pixel electrode pair, or four pixels are disposed in the region surrounded by the transparent partition walls 4. The configuration can be changed as appropriate, for example, by forming an electrode pair and arranging 16 microcapsules on the 4-pixel electrode pair. Then, the particles in the microcapsule move in a direction substantially perpendicular to the panel substrate, and display for each pixel, that is, dot display is performed.

  In the information display panel according to the present invention, as described later, when an observer views information displayed on the screen (information display screen area) from the substrate 2 side, the background attached to the substrate 1 side is provided. Can be visually recognized. Accordingly, in order to make it possible to visually recognize the background image, the information display screen area of the substrate 2 and the partition walls 4 provided in the corresponding area of the substrate 1 in FIGS. 1 to 3 are all transparent. It is necessary. Furthermore, when the substrates 1 and 2 are bonded to the partition walls 4 with an adhesive, the adhesive must also be transparent.

In the information display panel shown in FIGS. 1 to 3 in which a conductive film is formed as an electrode on the panel substrate, the substrate portion in the information display screen region is transparent, and the conductive film (electrode) provided in the information display screen region ), The conductive film on the observation side to be visually recognized is transparent, but the conductive film in the portion where the transparent partition on the back side is not formed may not be transparent. For example, even if the pixel electrode with TFT is opaque, the partition disposed around it may be transparent. In the case of the stripe electrode shown in FIG. 1, if the stripe electrode on the back side is made opaque, a part of the background image at the position of the transparent partition formed thereon cannot be displayed. However, even in this case, the remaining part of the background image can be displayed through the transparent partition formed in the gap between the adjacent stripe electrodes.
In the area corresponding to the information display screen area of the back side substrate, it is sufficient that at least the portion where the transparent partition walls are formed is transparent.

  Next, it is configured as a particle group including particles having optical reflectance and chargeability, and is configured as a particle group including at least two kinds of display media having different optical reflectance and charging characteristics (negatively charged white particles 3Wa). An information display panel in which display rewriting is performed by an external electric field forming unit using the white display medium 3W and the black display medium 3B configured as a particle group including the positively charged black particles 3Ba will be described.

In the example shown in FIGS. 4A and 4B, a pair of pixel electrodes is used as external electric field forming means. In this case, an information display panel is inserted between pixel electrodes facing up and down, and an electric field is applied using the pixel electrodes. For example, when the electric field forming means 7a of the external electric field forming means 7 in FIG. 4A forms an electric field such that the upper pixel electrode is a negative electrode and the lower pixel electrode is a positive electrode, The portion of the display medium to which is attached moves in the cell substantially perpendicular to the substrates 1 and 2. Then, as shown in FIG. 4B, the white display medium 3W and the black display medium 3B are reversed. Thereby, the observer can visually recognize information displayed by the black display medium 3B and the white display medium 3W.
4A and 4B show an example in which information is displayed on a white background screen, the information may be displayed on the white display medium 3W with the screen as a black background. As shown in FIGS. 4A and 4B, it is not necessary to associate the pixels with the cells. The color of the display medium is not necessarily limited to a combination of white and black, and any combination of colors may be used as long as they are different from each other.

As an external electric field forming means, a writing electrode such as a pen as shown in FIG. 5 can be used. In this case, the writing electrode and the conductive film (transparent solid film) provided on the back side of the display panel are faced up and down. Then, an electric field is applied using the writing electrode and the conductive film. For example, when the electric field is formed so that the external electric field forming means 7 in FIG. 5A is a negative electrode and the conductive film 8 of the back substrate is a positive electrode, the display medium in the portion to which the electric field is applied becomes a cell. As shown in FIG. 5B, the white display medium 3W and the black display medium 3B are reversed. Thereby, the observer can visually recognize information displayed by the black display medium 3B and the white display medium 3W.
5A and 5B show an example in which information is displayed on a white background screen, the information can also be displayed on the white display medium 3W with the screen as a black background. As shown in FIGS. 5A and 5B, the area where the writer electrode is grounded to the observation-side substrate can be a pixel. The color of the display medium is not necessarily limited to a combination of white and black, and any combination of colors may be used as long as they are different from each other. Also in these cases, it is only necessary that at least a portion where the transparent partition walls are formed is transparent in the area corresponding to the information display screen area of the back substrate. In the configuration shown in FIG. 5, an adhesive AD is disposed between the substrate 1 and the transparent partition wall 4, and the adhesive AD is also transparent.

  In addition to the above-described configuration, the display medium that can be driven by an electric field includes, in addition to the above-described configuration, at least two types of display media (for example, chargeable particles and insulating liquids having different optical reflectances). A white display medium 3W configured as a particle group including the negatively charged white particles 3Wa and a blue display medium 3BL configured as an insulating blue liquid can be used. A cholesteric liquid crystal can also be used. Furthermore, it is also possible to configure such that the particles are rotated between the substrates by making the optical reflectance and the charging polarity of each region of each particle half different from each other.

  Next, as described above, at least in the information display screen area, the background image, which is a feature of the present invention, is attached to the information display panel in which the substrate, the partition walls, the electrodes, and the adhesive are all transparent. And the formation method is demonstrated.

  In the information display panel of the present invention, the upper surface of the back side substrate that is the outside of the panel is colored with ink, or a sheet on which a background image is printed in advance is pasted on the back side substrate that is the outside of the panel. As a result, fixed information that cannot be rewritten is formed as a background image on the rear substrate on the outside of the panel. At this time, the optical reflectance of the background image and the optical reflectance of the display information rewritable by the display medium have different optical reflectances. As a result, when the viewer visually recognizes the information display panel, the display information on the display medium in the cell and the image that is the fixed information attached to the back side have different appearances so that they can be distinguished. Is displayed. By adopting such a configuration, in the present invention, in addition to display information that can be rewritten by the display medium in the cell, the observer can use a desired pattern (design, trade, etc.) applied to the information display screen area on the back side substrate. An image such as a fixed information such as a mark can be simultaneously obtained in the same information display screen area. Of course, the display information on the display medium can be a plain image, and only the background image can be displayed.

6A to 6D are diagrams schematically showing a manufacturing process of the information display panel of the present invention. Here, an information display panel having a structure in which a conductive film is not provided on the panel substrate is shown, and for the sake of easy understanding, the information display panel is shown with dimensions different from actual ones. FIGS. 6E and 6F are examples of the display state of the background image that can be visually recognized by the observer in each step of FIGS. 6A to 6C and (d-i, ii). Is shown. That is, the sectional view taken along line PP ′ in FIG. 6E corresponds to each of FIGS. 6A to 6C, and the sectional view taken along line PP ′ in FIG. d-i, ii).
In addition, the manufacturing process shown in this example is only one of the processes for manufacturing the information display panel of the present invention, and may be manufactured by other methods. In the present invention, it is necessary that the observer can observe a desired image as a background separately from the display information displayed by the display medium when viewing the display on the panel.

  First, a transparent partition 4 for forming a cell is formed on the transparent region 2 (information display screen region serving as an information display screen) of the observation side substrate (FIG. 6A). As a specific material of the partition wall, a transparent resist material is preferable. For example, in addition to a dry film resist material such as Alfo NIT2 (manufactured by Nichigo Morton) or PDF300 (manufactured by Nippon Steel Chemical Co., Ltd.), a liquid transparent resist material Can be used. As a method for forming the partition wall, a mold transfer method, a screen printing method, a sand blast, an additive method, and the like can be used. Among these, a photolithographic method and a mold transfer method, which are formation methods using a transparent resist material, are used. Preferably used. And it is preferable that the transparency of the partition walls 4 is high so that an image (fixed information) to be formed later on the back side substrate can be clearly displayed.

  The partition wall disposed between the panel substrates can have a function of securing a gap between the panel substrates and a function of forming cells by dividing a region where the display medium is disposed. A partition that serves both for cell formation and securing the gap between panel substrates is provided in the information display screen area of the information display panel, and is a transparent partition. A partition for securing the gap between the panel substrates is also provided outside the information display screen region, and the partition may be transparent or not transparent. These partition walls are formed by applying a photolithography technique using a commercially available resist material, or indenting a region that becomes a cell or making a hole with respect to a sheet material having a thickness of the partition wall height. A thing can be arranged and provided as a spacer. In the partition wall manufacturing method using a resist material, a transparent partition wall is obtained using a transparent resist, and a desired color partition wall can be obtained by adding a pigment of a desired color to the transparent resist. In the partition wall manufacturing method using a sheet-like spacer, a transparent partition wall can be obtained by using a transparent sheet, and a desired colored partition wall can be obtained by using a colored sheet. The sheet material is preferably a plastic material such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC). If it is a plastic material, a partition can be produced by denting a region to be a cell or making a hole.

  Next, for example, a black particle group including positively charged black particles and a white particle group including negatively charged white particles are displayed in a cell formed by being continuously or intermittently surrounded by the partition walls 4. It fills as a medium (3B and 3W) (FIG.6 (b)).

  And after arrange | positioning transparent adhesive AD on the partition 4, the back side board | substrate 1 is piled up and bonded together, and the filled display medium (3B and 3W) is enclosed between panel substrates (FIG.6 (c)).

  Thereafter, the desired image (fixed information such as design, trademark, etc.) is attached to the information display screen area on the outer surface of the back substrate 1, that is, the surface opposite to the observation substrate 2. The optical reflectivity of the part is set to be different from the optical reflectivity of the particle group (3W, 3B) arranged in the cell (FIG. 6 (d-i)).

As a method of attaching fixed information as an image to the information display screen area on the outer surface of the back substrate 1, that is, the surface opposite to the observation substrate 2, a printing method in which ink is applied using the outer surface as a printing surface. And a transfer film method. A hatched portion I in FIG. 6D-i shows a state in which ink forming a desired image is placed on the information display screen area on the back-side substrate 1. When the outer surface of the back side substrate 1 is partially colored in this way, a pattern as shown in FIG.
Here, for the sake of simplicity, all the display states shown in FIG. 6 are from only the region where the partition wall is formed (as viewed perpendicularly to the substrate) in the region of the back side substrate 1 to which the fixed information is attached as an image. The background image is depicted so as to be visible. However, as described above, a part of the observation-side substrate 2, the partition wall 4, and a part of the back-side substrate 1 in the information display screen area are all transparent. It is also possible to provide an area in which no display medium is arranged, and to obtain a background image from the area.
6A to 6D are cross-sectional views taken along line PP ′ in FIGS. 6E and 6F, and cross-sectional views at other locations are shown in FIG. It will be understood that these are different.

  The fixed information obtained as the background image can also be obtained, for example, by sticking a sheet St on which fixed information to be the background image has already been printed to the outer surface of the back substrate 1, that is, the side opposite to the observation substrate 2. Can be realized. FIG. 6 (d-ii) shows a state in which an image-attached sheet St on which a desired pattern (fixed information) is printed with ink or the like is bonded to the outer surface of the back side substrate. In this way, when a sheet with an image is attached to the outer surface of the back substrate, an image as shown in FIG. 6F is displayed to an observer who views the information display panel from the observation side. Will be. In the example of this figure, a state is shown in which a background image is displayed on a white background screen in which the white display medium in the cell is moved to the observation side.

  FIGS. 7A to 7D are information display panels when transparent stripe electrodes are provided, and are information display screens on the inner side surfaces (cell side) of the back side substrate 1 and the observation side substrate 2. Except that the transparent stripe electrodes 5 and 6 are provided in the region, the configuration and the forming process of the information display panel shown in FIG. Similarly, in FIGS. 7E and 7F, FIGS. 7A to 7C are cross-sectional views taken along line PP ′ of FIG. 7E, and FIGS. Each sectional drawing in line PP 'of Drawing 7 (f) is shown.

  Further, as shown in FIGS. 6 (d-ii) and 7 (d-ii), fixed information as a background image is formed on the sheet St by printing or the like, and the printed surface is formed on the back side substrate. In the configuration in which the sheet St is laminated, a color tone having a high reflectance such as white is used for the sheet St. On the other hand, it is preferable to use a color tone different from that of the sheet St for the background image formed by printing or the like thereon. According to such a configuration, for example, when performing black display on a white background using a white and black display medium as a display medium disposed in a cell, by printing a background image in red (not white or black), Over the entire screen, rewritable black character information and red fixed information as a background image thereof can be displayed more easily on a white background. The character information printed on the paper (sheet) can be viewed in the forward direction without being in the reverse character state. The color tone of the sheet is preferably a color tone having a high reflectance such as white. In this case, since the reflected light from the sheet surface enters the observer's eyes through the transparent partition, a bright display can be visually recognized.

  When the information display panel manufactured as described above is used, as shown in FIGS. 8A and 8B, the back side substrate 1 is on the lower side and the observation side substrate 2 is on the upper side. .

If the fixed information formed on the outside of the back side substrate 1 is a black solid image and the information display panel has a configuration in which transparent partition walls are arranged in a matrix, the fixed information (black) is a black matrix. Can do. Similarly, if the fixed information formed on the outside of the back substrate 1 is a solid white image and the information display panel has a configuration in which transparent partition walls are arranged in a matrix, the fixed information (white) is converted into a black matrix. It can be.
For example, on the outside of the back-side substrate 1, as fixed information, a black image is formed in half of the information display screen area and a white image is formed in the other half so that the black matrix effect can be obtained in the half of the screen. The half of the screen can be used properly so that the white matrix effect can be obtained.
As described above, the fixed information can be formed after the information display panel is formed. Therefore, fixed information corresponding to the purpose of the information display panel can be formed later without forming fixed information at the time of manufacture.

  Here, the shape of the partition 4 can be appropriately set as appropriate depending on the type of the display medium, the shape and arrangement of the electrodes to be arranged.

The width of the partition wall is adjusted to 2 μm to 100 μm, more preferably 5 μm to 50 μm, but it is not necessarily limited to this width.
As described above, the background image as fixed information attached on the back side substrate can be surely recognized from the region where the partition walls are formed (as viewed perpendicularly to the substrate). On the other hand, in a region where cells are formed when viewed perpendicular to the substrate, the display medium moves in the cells, so that the appearance changes depending on the position of the display medium. Therefore, if the width of the partition wall is adjusted to the above width, the observer can optimally recognize the background image as fixed information attached on the back side substrate. The width of the partition wall is set to 2 μm to 100 μm. If the partition wall width is too small to be less than 2 μm, the background image as fixed information existing in the partition wall region cannot be visually recognized. This is because if the thickness is larger than 100 μm, the background image as the fixed information is excessively emphasized and the display information on the display medium cannot be accurately recognized. And when the width | variety of a partition is 5 micrometers-50 micrometers, the background image as fixed information and the display information displayed by a display medium can be visually recognized in the balanced good state.

Moreover, the height of the partition wall is 10 μm to 500 μm, and more preferably 10 μm to 200 μm.
If the height of the partition wall is made too low to be less than 10 μm, the display medium cannot be enclosed in a sufficient amount in the cell, and the display medium may move freely after the enclosure because the space in the cell is narrow. It is not possible. In addition, if the height of the partition wall is set higher than 500 μm, a high voltage is required to form an electric field necessary for moving the particle group as the display medium. When the partition wall height is 10 μm to 200 μm, a sufficient amount of the display medium can be enclosed in the cell and can be freely moved, and the display medium is driven by an electric field generated at a low voltage. can do.

  In forming the partition walls, both rib methods in which ribs are formed after the ribs are formed on each of the opposing back side substrate and observation side substrate, and the single ribs that form ribs only on either the back side substrate or the observation side substrate are formed. There are methods, and these methods can be selected as appropriate.

Regardless of the method used to form ribs for partition walls, a transparent adhesive is disposed on the bonding surface between the ribs and the panel substrate, or the bonding surface between the ribs and the ribs. It is preferable that bubbles or the like enter the interface and the adhesive so that the transparency is not impaired.
Therefore, it is preferable to sufficiently remove air bubbles in the adhesive before placing the adhesive. The adhesive is preferably transparent. However, if the thickness is thin, the reflected light can be transmitted through the transparent partition wall. Therefore, the adhesive may be colored with a pigment. Examples of the adhesive include commercially available World Lock No. 798 (manufactured by Kyoritsu Chemical Industry Co., Ltd.) and World Lock No. CML-61 (manufactured by Kyoritsu Chemical Industry Co., Ltd.).

The cell shape formed by these partition walls is exemplified by polygons and circles such as triangles, squares, and hexagons when viewed from the vertical direction of the substrate, and the arrangement is exemplified by lattices, honeycombs, and meshes. Is done. Since the cell shape surrounded by the partition walls, that is, the display area by the display medium occupies a larger proportion of the screen, the display information by the display medium can be displayed in a good state. Particularly preferred is a honeycomb arrangement of hexagonal cells. In order to facilitate movement of the particle group serving as the display medium, the cell shape is preferably free from corners, and polygons with rounded corners are preferred.
Further, the transparent partition 4 formed in the information display screen area may not form a cell. The partition 4 may be any one that ensures a distance between two panel substrates, that is, a gap between the substrates. Therefore, the shape and arrangement can be appropriately selected and formed according to the image form of the fixed information formed on the outside of the back side substrate of the panel. In this way, it is possible to add a display of fixed information based on the shape and arrangement of the transparent partition walls.

  Hereinafter, as described above, an image as fixed information as a background is attached to the information display screen area on the back side substrate, and the optical reflectance of the background image and the optical information of the display information by the display medium are added. The characteristic configuration of the present invention in which the reflectivity has different optical reflectivity will be described more specifically with reference to actual examples. However, the present invention is not limited to the examples described below, and can be applied to various uses.

In the example of the information display panel shown in FIG. 9, it is assumed that the rewritable information displayed on the display medium is information including a confidential matter.
In this example, in the description of the manufacturing process of the information display panel, the character “secret” is displayed as an image attached to the colored portion shown in FIGS. 6 (f) and 7 (f), that is, the outer surface of the back side substrate 1. It is attached. In this case, an observer who sees the information display panel from the observation side substrate side 2 can recognize the character “secret” as a background image of display information formed by the display medium in the cell. On the other hand, the top secret information itself is displayed as an image in which dots are gathered in the information display screen area by driving a display medium arranged in the cell.

  In this way, if the word “secret” is attached to the back side substrate in advance, even when the display screen on the panel is copied to a non-rewritable paper medium, the confidential information displayed on the display medium ( In addition to the display information, the text information “secret” as a background image is also copied as a background together with the minutes. As a result, not only the rewritable confidential information displayed on the panel is printed and stored, but also the additional information “secret” can be printed and stored at the same time. Handling can be distinguished at a glance.

  Here, the display medium for displaying the confidential information is, for example, a white display medium and a black display medium as described above. In this case, the character “secret” as the background image has a color tone other than black and white. It is preferable to attach to the back side substrate by a light color. This is because the secret matter displayed on the black display medium is copied to the paper medium as a darker display. Therefore, when the colors of the display media are different, the character “secret”, which is the background image, can be added with another color.

  According to the present invention, as described above, additional information is displayed to such an extent that the content of the confidential matter is not difficult to read by adding light and shade to display information on the display medium and display fixed information as a background. Will be able to. Then, after copying the information that is a confidential item, the copied confidential item can be erased from the screen, and new confidential information can be rewritten on the panel.

  Next, each member which comprises the information display panel of this invention is demonstrated.

The observation-side substrate used in the present invention is preferably a material having at least an information display screen region that is transparent so that the display medium can be confirmed from the outside of the panel, a high visible light transmittance, and good heat resistance. is there. The other substrate on the back side is also a substrate that is at least partially transparent in the region facing the information display screen.
As long as the predetermined part mentioned above in the information display screen area | region is transparent as for an observation side board | substrate and a back side board | substrate, the other part does not need to be transparent. Further, it is possible to use a substrate in which the information display screen region is entirely transparent or a substrate in which the entire surface is transparent. As the observation side substrate and the back side substrate, organic materials such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene (PE), polycarbonate (PC), polyimide (PI), polyethersulfone (PES), acrylic, etc. A polymer substrate, a glass substrate, or a quartz substrate can be used.

When a plastic substrate is used as the panel substrate, the observation side plastic substrate contacts the glass surface of the copier when the information display panel is placed on the copier to copy the display information. It is possible to avoid damaging the glass surface.
Even in the case where a glass substrate is used as the panel substrate, in the present invention, a sheet or the like is formed as a background image on the outer surface of the rear substrate. Therefore, since the background image serves as a protective layer for the glass substrate with TFT pixel electrodes and the glass substrate with stripe electrodes on the information display panel side, damage and destruction can be prevented.

As a material for forming electrodes and conductive films, metals such as aluminum, silver, nickel, copper, and gold, indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), indium oxide, conductive Conductive oxides such as conductive tin oxide, antimony tin oxide (ATO), conductive zinc oxide, polyaniline, polypyrrole, polythiophene, such as poly (3,4-ethylenedioxythiophene) -poly- (styrenesulfonate)) (PEDOT: PSS) ) And the like, and are selected and used as appropriate. As a method for forming an electrode or a conductive film, a method of patterning the above-exemplified materials into a thin film by a sputtering method, a vacuum deposition method, a CVD (chemical vapor deposition) method, a coating method, etc. Or a method of patterning by mixing a conductive agent with a solvent or a synthetic resin binder and applying it. The thickness of the electrode or conductive film is determined in view of conductivity and light transmittance, and is 0.01 μm to 10 μm, preferably 0.05 μm to 5 μm.
It should be noted that a metal oxide-based transparent material such as ITO suitable as a conductive film provided in the information display screen region is less flexible than a metal material, particularly when the transparent conductive film is formed in a line shape. In order to prevent disconnection in the metal oxide material, it is preferable to use a metal fine wire in combination. The width of the fine metal wire provided in the information display screen area of the observation side substrate is preferably 1 μm to 10 μm so as not to disturb display.
With respect to the material and thickness of the conductive film provided outside the information display screen area, it is not necessary to consider light transmittance. Therefore, it is preferable to use a metal material as described above that has low electrical resistance and excellent flexibility.

  Further, the chargeable particles constituting the display medium capable of electric field driving will be described. The chargeable particles can contain a charge control agent, a colorant, an inorganic additive, and the like, if necessary, in the resin as the main component. 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, 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.

As yellow colorants, yellow lead, 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 yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, Indanthrene Brilliant Orange RK, Benzidine Orange G, Indanthren 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. The above colorant can be blended to produce chargeable particles of a desired color.

  The chargeable particles (hereinafter also referred to as “particles”) have an average particle diameter d (0.5) in the range of 1 μm 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. If the average particle diameter d (0.5) is smaller than this range, the cohesive force between the particles becomes too large, which hinders movement as a display medium.

Furthermore, regarding the particle size distribution, 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 the chargeable particles is uniform, and movement as a uniform display medium becomes possible.

  Furthermore, when a plurality of particle groups are used as the display medium, among the chargeable particles constituting the display medium used, the average particle diameter d ( It is important that the ratio of the average particle diameter d (0.5) of the chargeable particles having the minimum average particle diameter d (0.5) to 0.5) is 10 or less. Even if the particle size distribution Span is reduced, the chargeable particles having different charging characteristics move, so it is preferable that the particle size of each other can be easily moved as a display medium. Is in 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 the particle size distribution 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, when the display medium configured as a group of particles including the chargeable particles is driven in a gas (including vacuum) space, the gas management of the void portion surrounding the display medium between the panel substrates can be performed. It is important and contributes to improved 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.
1A, 1B, 2A and 2B, the gaps are defined as electrodes 5 and 6 (electrodes inside the substrate) from the portion sandwiched between the opposing substrate 1 and substrate 2. In this case, the gas portion in contact with the so-called display medium excluding the occupied portion of the display medium 3, the occupied portion of the partition wall 4, and the seal portion of the 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 the panel so that the humidity is maintained. For example, the display medium is filled and the panel is assembled in a predetermined humidity environment. It is important to apply a sealing material and a sealing method to prevent it.

The distance between the substrates in the information display screen area of the information display panel targeted by the present invention is not limited as long as the display medium can be driven and the contrast can be maintained, but is usually 10 μm to 500 μm, preferably 10 μm to 200 μm, Preferably, it is adjusted to 10 μm to 100 μm. The distance between the substrates is adjusted by the thickness of the transparent partition wall 4 and the transparent adhesive AD.
When the information display panel is of a charged particle gas (including vacuum) space movement method, the distance between the substrates is adjusted in the range of 10 to 100 μm, preferably 10 to 50 μm. Furthermore, the volume occupation ratio of the display medium in the gas space between the substrates is preferably 5 to 70%, more preferably 5 to 60%. When it exceeds 70%, the movement of particles as a display medium is hindered, and when it is less than 5%, the contrast tends to be unclear.
Although there is a system in which the charged particles are moved and displayed, the charged particles are sealed in a cell together with an insulating liquid. However, the present invention can also be applied to an information display panel of such a system.

The information display panel of the present invention is a display unit for mobile devices such as notebook computers, PDAs, mobile phones, handy terminals, electronic paper such as electronic books, electronic newspapers, and electronic manuals (instruction manuals), signs, posters, and blackboards. Billboards such as billboards, calculators, home appliances, automotive supplies, point displays, card displays such as IC cards, electronic advertising, electronic point of purchase (POP), electronic price tags, electronic shelf labels, Electronic musical score, display unit of RF-ID device, display unit connected to external display rewriting means (so-called rewritable paper), display part using external electric field forming means (so-called rewritable paper) ).
For example, the information display panel of the present invention is used as an electronic paper for preparing the minutes, and the minutes of the meeting held by five interested parties are created as electronic data on the electronic paper, and then a copy of the electronic paper screen is created. If you create 5 sheets and store the paper media that each person copied, the created electronic data can be erased from the display screen of the electronic paper, and then the display screen of the electronic paper can be used for a new display purpose. Can be provided.

DESCRIPTION OF SYMBOLS 1 Back side board | substrate 2 Observation side board | substrate 3W White display medium 3Wa White negatively charged particle 3B Black display medium 3Ba Black positively charged particle 4 Transparent partition 5, 6 Conductive film (electrode)
7 Electric field forming means 8 Conductive film (electrode)
AD transparent adhesive I ink St sheet BM black matrix material

Claims (6)

At least a part of the transparent substrate on the observation side, at least a transparent part on the opposite side of the transparent part of the observation side substrate, and a transparent to ensure a distance between the observation side substrate and the rear side substrate In an information display panel having a partition wall and a display medium disposed between the substrates and capable of electric field driving, and rewriting display information by driving the display medium with an electric field,
An information display panel, wherein an image serving as a background of the display information is formed on a transparent portion of the back side substrate on a surface opposite to the observation side substrate.   The information display panel according to claim 1, wherein an optical reflectance of the background image is different from an optical reflectance of the display medium.   The display medium is composed of a white particle group and a black particle group having different charging polarities, and the background image is formed of a color other than white and black and having a color tone lighter than black. The information display panel according to claim 1 or 2.   A stripe electrode as a transparent conductive film is provided on the observation side substrate, a stripe electrode is provided as a transparent conductive film on the back side substrate, and opposing electrode pairs formed so that the stripe electrodes intersect each other are arranged in a matrix. The information display panel according to claim 1, wherein the information display panel is characterized.   A common electrode as a transparent conductive film is provided on the observation side substrate, a pixel electrode with a thin film transistor (TFT) is provided as a conductive film on the back side substrate, and a counter electrode pair formed by facing the common electrode and the pixel electrode in a matrix arrangement The information display panel according to claim 1, wherein a transparent partition wall is disposed between adjacent pixel electrodes with thin film transistors (TFTs). In the manufacturing method of the information display panel as described in any one of Claims 1-5,
An information display panel manufacturing method comprising forming an image as a background of the display information on the surface of the back substrate.

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