JP2007322900A - Color filter for display panel, and information display panel using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter for a display panel, which can be applied to a display media driving type display panel or an information display panel, having flexibility and is superior in display quality and display reliability, and to provide an display media driving type information display panel that uses the same and is superior in color display performance. <P>SOLUTION: The color filter for a display panel is obtained by curing a color filter material, containing at least a color material and a binder resin. The color filter comprises the color filter material, exhibiting characteristics after being cured such that the surface hardness is ≥300 [mN/mm<SP>2</SP>], as measured by deforming the surface of a sample by 10% by applying pressure to the surface of the sample with a push-in needle having a pyramidal fine tip; the surface hardness of the sample is at least H for pencil hardness; the tensile modulus is 10-100 MPa; and the elongation at break is 2-500%. In the information display panel, color display is performed by using the color filter for the display panel as three primary-color color filters 11R, 11G, and 11B. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a color filter for a display panel, in particular, a color filter for a display panel obtained by arranging a color filter material (ink) on a substrate such as a flexible substrate using an inkjet method, and the display panel The present invention relates to an information display panel configured to perform color display using a color filter as a constituent member, and more particularly to an information display panel in which the entire panel is flexible.

  Conventionally, as a method for manufacturing a color filter for a display panel, there have been a manufacturing method applying a photolithography method and a manufacturing method applying an ink jet method. As a manufacturing method applying the inkjet method, a partition is formed in a matrix shape on a transparent substrate with a material having low wettability with respect to ink so as to divide the color filter formation region, and then the inkjet method is used for color. There is a method of forming a color filter by applying a filter material (ink) into a partition (see, for example, Patent Document 1). In addition, in a color display device using a method that is not a particle movement type, such as a liquid crystal display device, there is a conventional technique for performing color display by arranging a color filter on a panel constituting the color display device. The manufacturing method described above is applied to manufacturing such a color filter for a liquid crystal display panel. Patent Document 1 discloses “a technique for producing a color filter for a liquid crystal display device using an ink having a pencil hardness of 3H or more by an inkjet method”, but “the color filter is a display medium (particle It is not disclosed that it can be used sufficiently for a drive-type information display device.

JP 2002-174713 A

However, when the above-described conventional color filter for a liquid crystal display panel is used in a particle movement type display device, it is provided inside the panel substrate. In this case, the color filter arranged on the panel substrate is a display medium ( Display color particles). In such a particle movement type display device, since the display medium (colored particles for display) moves in the air at high speed, the display medium (colored particles for display) collides with the panel substrate at high speed. When arranged so as to be in contact with the particles, the surface hardness of the conventional color filter is insufficient for the display medium (colored particles for display) that collides with the panel substrate at high speed. Therefore, even if there is no problem in the initial display state, the display medium (colored particles for display) is buried in the color filter as the number of display rewrites increases, in other words, as the number of movements of the display medium increases. There is a problem that the display performance deteriorates due to deformation of the display.
In addition, since the color filter used in the above-described conventional liquid crystal display device or the like is provided on a glass substrate, flexibility is not required. On the other hand, an information display panel (electronic paper) has been proposed in which a flexible member is used as a panel constituent member to give flexibility to the entire display panel so that it can be bent or rounded. However, when the above-described color filter for a liquid crystal display panel is used in a display medium moving display panel that is flexible and can be rolled or bent, the flexibility is insufficient. The color filter is damaged, the color filter is cracked, the color filter is deformed, and the display performance is deteriorated, so that an information display panel (electronic paper) capable of color display cannot be realized. There was a problem.

It is an object of the present invention to provide a display panel color filter excellent in display quality and display reliability, which can be applied to a display medium drive type display panel using particles as a display medium and a flexible information display panel. The first purpose.
The present invention provides a display medium drive type information display panel excellent in color display using the display panel color filter, and information having flexibility in color display using the display panel color filter. A second object is to provide a display panel.

In order to achieve the first object, the color filter for display panel according to claim 1 of the present invention is a color filter for display panel obtained by curing a color filter material containing at least a color material and a binder resin. It is characterized by comprising a color filter material having a hardness of 300 [mN / mm ² ] or more measured when it is deformed by 10% by applying pressure with a push-in needle having a pyramidal minute tip on the surface thereof.
In order to achieve the first object, a color filter for display panel according to claim 2 of the present invention is a color filter for display panel obtained by curing a color filter material containing at least a color material and a binder resin. The surface is made of a color filter material having a pencil hardness of H or more.
In order to achieve the first object, a color filter for display panel according to claim 4 of the present invention is a color filter for display panel obtained by curing a color filter material containing at least a color material and a binder resin. The rate is 10 to 100 MPa, and the elongation at break is 2 to 500%.

  As a suitable example of the color filter for display panel of the present invention, the binder resin contains a photocurable resin, the tensile elastic modulus is 20 to 60 MPa, the elongation at break is 2 to 200%, and It has been produced using an ink jet method.

In order to achieve the second object, an information display panel according to claim 7 of the present invention is transparent and flexible in which the color filter for display panel according to any one of claims 1 to 6 is formed. A resin substrate and another flexible substrate are used as constituent members.
In order to achieve the second object, an information display panel according to an eighth aspect of the present invention encloses a display medium in a space partitioned by a partition between at least one transparent substrate, and the display medium is an electric field. An information display panel that displays information such as an image by moving the display panel according to any one of claims 1 to 6, wherein the display panel color filter is formed of three primary colors (R: red, G: green, B: blue). It is characterized in that it is configured to perform color display using it as a purple color filter.
As a preferred example of the information display panel of the present invention, a display medium driven by an electric field is composed of colored particles for display having chargeability and optical reflectance, and the state once displayed is as follows. Until the display rewrite operation is completed.

According to the color filter for display panel of the first aspect of the present invention, the color filter for display panel obtained by curing the color filter material containing at least the color material and the binder resin has a pyramidal microtip on the surface after curing. Since it is made of a color filter material having a hardness of 300 [mN / mm ² ] or more measured when it is deformed 10% by applying pressure with a push-in needle having durability, durability when display rewriting is repeated many times Improved. Therefore, this display panel color filter is a display panel color filter excellent in display quality and display reliability when applied to a display medium drive type display panel or a flexible information display panel.

  According to the color filter for a display panel of claim 2 of the present invention, in the color filter for a display panel obtained by curing a color filter material containing at least a color material and a binder resin, the surface after curing has a pencil hardness of H. Since it consists of the above color filter material, durability when display rewriting is repeated many times is improved. Therefore, this display panel color filter is a display panel color filter excellent in display quality and display reliability when applied to a display medium drive type display panel or a flexible information display panel.

  According to the color filter for display panel of claim 4 of the present invention, in the color filter for display panel in which the color filter material containing at least the color material and the binder resin is cured, the tensile elastic modulus is 10 to 100 MPa. In addition, since the elongation at break is 2 to 500%, when the tensile modulus exceeds 100 MPa, cracks and peeling easily occur due to stress caused by bending and the like, and when the tensile modulus is less than 10 MPa, color When forming a filter, cracks and peeling are likely to occur due to stress caused by curing shrinkage, and when the elongation at break exceeds 500%, the elongation caused by bending or the like is difficult to return to the original, and peeling is likely to occur. And bending when the elongation at break is less than 2% It may easily occur cracks or peeling due to the stress caused by is prevented. Therefore, this display panel color filter is a display panel color filter excellent in display quality and display reliability when applied to a display medium drive type display panel or a flexible information display panel.

  According to the information display panel of claim 7 of the present invention, a transparent and flexible resin substrate on which the color filter for display panel according to any one of claims 1 to 6 is formed, and the other Since the flexible substrate is used as the constituent member, it is possible to provide a flexible information display panel having excellent color display properties.

According to the information display panel of claim 8 of the present invention, the display medium is sealed in the space partitioned by the partition between the opposing substrates at least one of which is transparent, and the display medium is moved by an electric field to An information display panel for displaying information, wherein the color filter for display panel according to any one of claims 1 to 6 is used as a color filter for three primary colors (R: red, G: green, B: blue-violet). Color display, it is possible to provide a display medium drive type information display panel with excellent color display properties. If each of the opposing substrates is a flexible resin substrate, color display is possible. An information display panel having excellent display properties and flexibility can be provided.
A display in which the display medium driven by the electric field is composed of colored particles for display having chargeability and optical reflectance, and the state once displayed is maintained until the next display rewriting operation. By using the medium, an information display panel having a display memory property can be obtained.

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

  First, the information display panel of the present invention configured using the display panel color filter of the present invention will be described. In the information display panel 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, a Coulomb force, or the like, and the display medium changes a moving direction 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 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.

The principle configuration of the information display panel of the present invention will be described with reference to FIGS.
In the example shown in FIG. 1A, at least two or more types of display medium 3 (here, a group of particles of display white particles 3Wa) having different optical reflectivity and charging characteristics composed of at least one type of particles. Generated by applying a voltage between an electrode 5 provided on the substrate 1 and an electrode 6 provided on the substrate 2. Depending on the electric field to be moved, the substrate 1 and 2 are moved vertically to make the black display medium 3B visually recognized by the observer, or the white display medium 3W is visually recognized by the observer. It is carried out. In the example shown in FIG. 1A, a partition 4 is provided between the substrates 1 and 2 in a lattice shape to form a cell. In addition, in FIG. 1A, the partition in front is omitted.
In the example shown in FIG. 1B, one type of display medium 3 having optical reflectivity and chargeability composed of at least one type of particles (here, white display consisting of a group of particles of display white particles 3Wa). The medium 3W) is moved in a direction parallel 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. The white display medium 3 </ b> W is visually recognized by an observer to display white, or the color of the electrode 6 or the film substrate 1 is visually recognized by the observer to display the color of the electrode 6 or the substrate 1. In the example shown in FIG. 1B, for example, a grid-like partition wall 4 is provided between the substrates 1 and 2 to form a cell. In addition, in FIG. 1B, the partition in front is omitted.
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.

  Next, various configuration examples of the information display panel of the present invention will be described with reference to FIGS. 2 (a) and 2 (b) to FIGS. 5 (a) and 5 (b).

The information display panel shown in FIGS. 2A and 2B is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three. In addition, two types of display media 3 (here, a white display medium 3W composed of a group of particles of display white particles 3Wa and a display for display) having different optical reflectivities and charging characteristics for each pixel are formed between the air holes in the pixels. Black display medium 3B composed of particles of black particles 3Ba), and three primary color filters 11R, 11G, and 11B are provided on the electrode 6 of the transparent substrate 2 on the display surface side. 2 is configured as a charged particle in-air drive type information display panel that displays information such as images in color by moving the display media 3W and 3B by applying a voltage to the electrodes 5 and 6 provided in FIG. Since the electrode 5 and the transparent electrode 6 are line electrodes in the case of FIG. 2A, they are passively driven, and in the case of FIG. In addition, when the display surface side transparent substrate 2 and the back surface side substrate 1 are flexible substrates such as film substrates (for example, resin substrates), they are flexible and can be rolled or bent. It becomes an information display panel.
When performing color display, a unit (unit cell) including three pixels including any one of the display media 3W and 3B and the three primary color filters as a set (unit cell) is included in this pixel unit. By performing independent display medium movement for each pixel, color display by combining three colors can be performed.

The information display panel shown in FIGS. 3A and 3B is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three. In addition, two types of display media 3 (here, a white display medium 3W composed of a group of particles of display white particles 3Wa and a display for display) having different optical reflectivities and charging characteristics for each pixel are formed between the air holes in the pixels. A black display medium 3B composed of a group of black particles 3Ba) is encapsulated, and three primary color filters 11R, 11G, and 11B are provided on the display surface side transparent substrate 2, and an electrode 6 is provided on each color filter. Charged particle air-driven information display panel that displays information such as images in color by moving the display media 3W and 3B by applying a voltage to the electrodes 5 and 6 provided on the two substrates 1 and 2. It is configured as Le. Since the electrode 5 and the transparent electrode 6 are line electrodes in the case of FIG. 3A, they are passively driven, and in the case of FIG. 3B, they are individual electrodes and are therefore active driven. In addition, when the display surface side transparent substrate 2 and the back surface side substrate 1 are flexible substrates such as film substrates (for example, resin substrates), they are flexible and can be rolled or bent. It becomes an information display panel.
When performing color display, a unit (unit cell) including three pixels including any one of the display media 3W and 3B and the three primary color filters as a set (unit cell) is included in this pixel unit. By performing independent display medium movement for each pixel, color display by combining three colors can be performed.

The information display panel shown in FIG. 4A is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three pixels. The two types of display mediums 3 (here, the white display medium 3W composed of a group of white particles 3Wa for display and the black particles 3Ba for display), which have different optical reflectivities and charging characteristics for each pixel. (Showing a black display medium 3B made of particles), and the primary color filters 11R, 11G, and 11B are provided on the electrode 6 of the display surface side transparent substrate 2, and the two substrates 1 and 2 are provided. The display medium 3W, 3B is moved by applying a voltage to the electrodes 5, 6 to display information such as images in color, and is configured as a charged particle insulating liquid drive type information display panel. The electrode 5 and the transparent electrode 6 are active electrodes because they are individual electrodes in the case of FIG. 4A, but may be passively driven as line electrodes. In addition, when the display surface side transparent substrate 2 and the back surface side substrate 1 are flexible substrates such as film substrates (for example, resin substrates), they are flexible and can be rolled or bent. It becomes an information display panel.
The information display panel shown in FIG. 4B is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three pixels. The two types of display mediums 3 (here, the white display medium 3W composed of a group of white particles 3Wa for display and the black particles 3Ba for display), which have different optical reflectivities and charging characteristics for each pixel. (A black display medium 3 </ b> B composed of a particle group) is encapsulated, and three color filters 11 </ b> R, 11 </ b> G, 11 </ b> B are provided on the display surface side transparent substrate 2, and a pair provided outside the two substrates 1, 2. The display medium 3W, 3B is moved by applying a voltage to the electrodes, and information such as an image is displayed in color in a charged particle air driven type information display panel.
When performing color display, a unit (unit cell) including three pixels including any one of the display media 3W and 3B and the three primary color filters as a set (unit cell) is included in this pixel unit. By performing independent display medium movement for each pixel, color display by combining three colors can be performed.

The information display panel shown in FIG. 5A is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three pixels. Each type of display medium 3 (here, a white display medium 3W composed of a group of white particles 3Wa for display) is sealed for each pixel, and the display surface side transparent substrate 2 is sealed. Three primary color filters 11R, 11G, and 11B are provided for each pixel, an electrode 5 and a black plate 12B are provided for each pixel on the back side substrate 1, a transparent electrode 6 is provided on the black plate 12B, and voltages are applied to the electrodes 5 and 6. Is applied to the white display medium 3W to display information such as an image in color in a charged particle air driven information display panel.
The information display panel shown in FIG. 5B is composed of pixels in which a plurality of cells partitioned by a partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1 are further divided into three, Each type of display medium 3 (here, a black display medium 3B composed of a group of black particles 3Ba for display) is sealed for each pixel, and the display surface side transparent substrate 2 is sealed. Three primary color filters 11R, 11G, and 11B are provided for each pixel, an electrode 5 and a white plate 12W are provided for each pixel on the back side substrate 1, a transparent electrode 6 is provided on the white plate 12W, and voltages are applied to the electrodes 5 and 6. Is applied, and the black display medium 3B is moved to display information such as an image in color in a charged particle air driven information display panel.
5A and 5B, when the display surface side transparent substrate 2 and the back surface side substrate 1 are flexible substrates such as a film substrate (for example, a resin substrate), there is flexibility. An information display panel that can be rolled and bent.
When performing color display, a unit (unit cell) including three pixels including any one of the display media 3W and 3B and the three primary color filters as a set (unit cell) is included in this pixel unit. By performing independent display medium movement for each pixel, color display by combining three colors can be performed.

Next, an example of a method for manufacturing an information display panel using the display panel color filter of the present invention will be described. This manufacturing method can be applied to an information display panel having a configuration in which no black matrix is provided, such as the information display panel shown in FIGS.
First, a line-shaped transparent ITO electrode 6 is provided on one surface of the display surface side transparent substrate 2. At this time, it is preferable to provide alignment marks at the four corners of the substrate simultaneously with the formation of the transparent ITO electrode. Next, corresponding to each ITO electrode, a red filter 11R, a green filter 11G, and a blue-purple filter 11B are repeatedly formed on the surface of the substrate opposite to the surface on which the ITO electrode and the alignment mark are provided. A color filter is formed by an inkjet method. In the above-described example, the color filter including the red filter 11R, the green filter 11G, and the blue-purple filter 11B is used as an example of the color filter. However, the present invention is not limited to this, and other colors such as cyan, A color filter composed of a combination of magenta and yellow can also be used. Moreover, although the ITO electrode was provided as an electrode, the electrode of another material can be used if it is transparent and has electroconductivity.
Moreover, the color filter material of the present invention can be suitably applied to a photolithographic method other than the ink jet method, and a color filter having a sufficient surface hardness can be obtained.

  Next, another example of a method for manufacturing an information display panel using the display panel color filter of the present invention will be described. In this manufacturing method, since the “process for providing a black matrix” is added to the manufacturing method for the information display panel, description of the same steps as the manufacturing method for the information display panel is omitted. In this manufacturing method, information on a configuration in which a black matrix such as the information display panel shown in FIGS. 2 (a), 2 (b), 3 (a), 3 (b), 5 (a), 5 (b) is provided. The information display panel shown in FIGS. 2A, 2B, 3A, 3B, 5A, and 5B can be applied to a display panel. On the transparent substrate 2 side, a black matrix 13 having a function as a bank for preventing diffusion of the color filter material outside the arrangement region is provided. Hereinafter, the manufacturing method of the color filter of this invention is demonstrated based on Fig.6 (a)-(h).

[In the case of an information display panel in which the electrode is in contact with the display medium]
First, as shown in the sectional view of FIG. 6A and the plan view of FIG. 6B, a bank is formed by providing the black matrix 13 on the display surface side transparent substrate 2. Next, as shown in the cross-sectional view of FIG. 6C and the plan view of FIG. 6D, the three primary colors are formed by disposing curable ink, which is a color filter material, in the opening of the bank by the inkjet method. Filters 11R, 11G, and 11B are provided. At this time, the upper surface of the black matrix 13 and the upper surfaces of the color filters 11R, 11G, and 11B are made flat. Thereafter, the electrodes 6 are formed on the color filters 11R, 11G, and 11B, respectively.
[In the case of an information display panel in which the color filter layer is in contact with the display medium]
First, electrodes are patterned on the substrate 2 with a transparent conductive film to form an ITO electrode pattern 6 shown in the cross-sectional view of FIG. 6E and the plan view of FIG. Next, as shown in the plan view of FIG. 6F, a black matrix (bank) 13 is formed between the ITO electrode patterns 6. Next, as shown in the sectional view of FIG. 6G and the plan view of FIG. 6H, a color filter material (for example, curable ink) is formed on the ITO electrode 6 in the opening region of the black matrix (bank) 13. ) Are arranged by an ink jet method to form the three primary color filters 11R, 11G, and 11B.

Next, a display panel color filter (hereinafter also referred to as a color filter) of the present invention will be described. The conditions required for the color filter of the present invention include the following conditions.
(1) A hardness measured when a surface of a color filter material containing at least a color material and a binder resin is cured by applying pressure with a pressing needle having a pyramid-shaped minute tip and deformed by 10% is 300. It is a color filter for a display panel made of a color filter material having [mN / mm ² ] or more.
The hardness (Fischer hardness) measured when pressure is applied by a pressing needle having a pyramidal minute tip on the surface of the color filter and deformed by 10% is measured. When the hardness is 300 [mN / mm ² ] or more, it can be suitably used as the color filter of the information display panel of the present invention. When the hardness is larger, the display rewriting is repeated many times. Durability performance is improved.
In the present invention, the reason why the hardness of the color filter is defined as 300 [mN / mm ² ] or higher when the color filter is deformed by 10% is that the color filter is deformed by 10%. If the measured hardness is less than 300 [mN / mm ² ], the color filter hardness is too low, and even if there is no problem in the initial display state, in other words, the display medium increases as the number of display rewrites increases. This is because as the number of times of movement increases, the display medium (particles) is buried in the color filter, or the color filter is deformed and the display performance deteriorates.

(2) A color filter for a display panel comprising a color filter material having a pencil hardness of H or higher on the surface after curing a color filter material containing at least a color material and a binder resin.
If the color filter surface hardness is defined as pencil hardness of H or higher and the pencil hardness is H or higher, the color filter can be suitably used as the color filter of the information display panel of the present invention. Specifically, the surface of the color filter on the side in contact with the display medium is evaluated by rubbing with a pencil. The higher the pencil hardness is, the higher the durability, the better the durability performance when the display rewriting is repeated many times.
In the present invention, the reason why the hardness of the color filter is defined as H or higher in pencil hardness is that when the pencil hardness is less than H, the hardness of the color filter is too low and there is no problem in the initial display state. However, as the number of display rewrites increases, in other words, as the number of movements of the display medium increases, the display medium (particles) is buried in the color filter, or the color filter is deformed and the display performance deteriorates. It is because it ends up.
(3) The display panel color filter is made of a color filter material containing a photocurable resin as a binder resin.

(4) A color filter for a display panel having a tensile elastic modulus of 10 to 100 MPa and an elongation at break of 2 to 500%. Preferably, the color filter for a display panel has a tensile elastic modulus of 20 to 60 MPa and a breaking elongation of 2 to 200%.
The reason why the tensile elastic modulus and elongation at break of the color filter are defined within the above range is as follows. First, with respect to the tensile elastic modulus, when the tensile elastic modulus exceeds 100 MPa, cracking or peeling is likely to occur due to stress caused by bending or the like, and when the tensile elastic modulus is less than 10 MPa, the color filter This is because cracks, peeling, and the like are likely to occur due to stress caused by curing shrinkage. In addition, regarding the breaking elongation, when the breaking elongation exceeds 500%, the elongation caused by bending or the like is difficult to return to the original, so that peeling easily occurs, and the breaking elongation is less than 2%. This is because cracks and peeling easily occur due to stress generated by bending or the like.
(5) A color filter for a display panel manufactured using an ink jet method.
From the viewpoint of productivity in production, it is preferable to use an ink jet method, but of course, a color filter for a display panel produced by using a photolithography method may be used.

According to the information display panel of the present invention, the display medium 3 is sealed in the space partitioned by the partition wall 4 between the display surface side transparent substrate 2 and the back surface side substrate 1, and the display medium 3 is moved by an electric field to generate an image or the like. In the information display panel of the present invention for displaying the above information, color display using the color filters for display panels satisfying at least one of the conditions (1) to (5) as the three primary color filters 11R, 11G, and 11B Thus, the display medium driving type information display panel having excellent color display properties is obtained. In addition, when each of the display surface side transparent substrate 2 and the back surface side substrate 1 is a flexible substrate, a flexible information display panel having excellent color display properties is obtained.
In addition, according to the information display panel of the present invention, the display surface side on which the color filters 11R, 11G, and 11B satisfying at least one of the conditions (1) to (5) are formed is transparent and flexible. Since the resin substrate 2 and the other flexible substrate 1 are used as constituent members, a flexible information display panel having excellent color display properties is obtained.
According to the information display panel of the present invention, the display medium driven by the electric field is composed of colored particles for display having chargeability and optical reflectance, and the state once displayed is By using a display medium that is held until the next display rewriting operation, an information display panel having a display memory property can be obtained.

Further, according to the color filter for display panel of the present invention, the color filters 11R, 11G, and 11B satisfying at least one of the above conditions (1) to (5) are used. When it is applied to an information display panel having a property, it becomes a color filter for a display panel excellent in display quality and display reliability.
In addition, according to the information display panel of the present invention, since the color filter layers of the three primary colors have an appropriate surface hardness, the generation of colored particles for display that cannot be driven by being embedded in the substrate is suppressed, and the driving of the particles Since the number of particles that are stuck to the substrate and do not move during display rewriting is reduced, display contrast is reduced.

In the present invention, the color filter hardness is preferably measured by a Fischer hardness meter (manufactured by Fischer Instruments). Hereinafter, a method for measuring color filter hardness using a Fischer hardness tester will be described.
<Measurement method of color filter hardness>
First, a substrate on which a color filter is formed is placed on a measurement plate. The measurement plate is set on the Fischer hardness tester HU200 (manufactured by Fischer Instruments), and the position of the measurement plate is adjusted so that the color filter portion is directly below the indenter while viewing the image of the CCD camera attached to the apparatus.
As the indenter, a tip in which the tip of the indenter for measuring the Vickers hardness is polished so as to be a square having a side of 50 μm is used. The indenter is lowered onto the color filter, and the load is applied at a constant speed (for example, 1.7 mN / sec) from the point where the indenter and the color filter are in contact to deform the color filter. The deformation of the color filter under each load is observed, and the magnitude of the load when the deformation of 10% with respect to the thickness of the color filter occurs is the hardness of the color filter.

  Hereafter, each member which comprises the color filter for display panels of this invention is demonstrated.

[Binder resin]
What added the hardening | curing agent is used for the binder resin contained in a color filter material.
As a binder contained in the thermosetting color filter material (thermosetting ink), a combination of a known resin and a crosslinking agent can be used. Specifically, a melamine resin, a hydroxyl group or a carboxyl group-containing polymer and melamine, a hydroxyl group or Carboxyl group-containing polymer and polyfunctional epoxy compound, hydroxyl group or carboxyl group-containing polymer and fibrin reactive compound, epoxy resin and resole resin, epoxy resin and amines, epoxy resin and carboxylic acid or acid anhydride, epoxy compound, natural Resin or acrylic resin, polyester resin, polyurethane resin, polyvinyl resin, amino resin, epoxy resin, polyether resin, etc. are used, especially acrylic resin is preferably used. Color filter material (ink) 0.1 to 20% by weight relative to the weight, is preferably added in a range of 0.2 to 15 wt%.
In addition, as a photocurable color filter material binder and a photocurable binder, there are ultraviolet (UV) curable binders, which are mainly composed of a prepolymer, a monomer, a photoinitiator, and a coloring material. Etc. become binders.
As the prepolymer, any of prepolymers such as polyester acrylate, polyurethane acrylate, epoxy acrylate, polyether acrylate, oligo acrylate, alkyd acrylate, polyol acrylate, and silicon acrylate can be used without any particular limitation.
Monomers include vinyl monomers such as styrene and vinyl acetate; monofunctional acrylic monomers such as n-hexyl acrylate and phenoxyethyl acrylate; diethylene glycol diacrylate, 1,6-hexanediol diacrylate, hydroxypiperic acid ester neopentyl glycol diacrylate , Polyfunctional acrylic monomers such as trimethylolpropane triacrylate, dipentaerystol hexaacrylate, acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, benzyl acrylate, benzyl methacrylate, Use styrene, polystyrene macromonomer, polymethylmethacrylate macromonomer, etc. It can be.
The prepolymer and the monomer may be used alone or in combination of two or more.
Photopolymerization initiators are isobutyl benzoin ether, isopropyl benzoin ether, benzoin ethyl ether, benzoin methyl ether, 1-phenyl-1,2-propadion-2-oxime, 2,2-dimethoxy-2-phenylacetophenone, benzyl, hydroxy Cyclohexyl phenyl ketone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzophenone, chlorothioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, 2-methylthioxanthone, chlorine-substituted benzophenone, halogen-substituted alkyl -From allyl ketone etc., what can obtain desired curability can be selected and used.
In addition, photoinitiators such as aliphatic amines and aromatic amines; and photosensitizers such as thioxanthone may be added as necessary.

[Coloring material: Color filter colorant]
Any one of organic colorants and inorganic colorants can be selected and used in accordance with a desired color such as R, G, and B.
As the organic colorant, for example, dyes, organic pigments, natural pigments, and the like can be used.
Moreover, as an inorganic coloring agent, an inorganic pigment, an extender pigment, etc. can be used, for example.
As the colorant, either a dye or a pigment can be preferably used.
For example, as the dye, C.I. I. Acid Red 118, C.I. I. Acid Red 254, C.I. I. Acid Green 25, C.I. I. Acid Blue 113, C.I. I. Acid Blue 185, C.I. I. Acid Blue 7 and pigments include C.I. I. Pigment red 177, C.I. I. Pigment red 5, C.I. I. Pigment red 12, C.I. I. Pigment green 36, C.I. I. Pigment blue 209, C.I. I. Pigment blue 16 and the like, but are not limited thereto.
Examples of organic pigments include azo pigments such as azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, Examples thereof include polycyclic pigments such as quinophthalone pigments, and dye lakes.
Examples of the inorganic pigment include oxides such as titanium oxide, bengara, chromium oxide, and iron black, cadmium yellow, chromium vermilion, bitumen, ultramarine blue, and yellow iron oxide.
Among these, organic pigments are preferably used because they have high color developability and high heat resistance.
Preferable organic pigments include, for example, compounds classified as Pigments in the Color Index (CI; issued by The Society of Dyers and Colorists), specifically, the following Color Index (CI) numbers. Can be mentioned.
CI Pigment Yellow 1, CI Pigment Yellow 3, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 14, CI Pigment Yellow 15, CI Pigment Yellow 16, CI Pigment Yellow 17, CI Pigment Yellow 20, CI Pigment Yellow 24, CI Pigment Yellow 31, CI Pigment Yellow 55, CI Pigment Yellow 60, CI Pigment Yellow 61, CI Pigment Yellow 65, CI Pigment Yellow 71, CI Pigment Yellow 73, CI Pigment Yellow 74, CI Pigment Yellow 81, CI Pigment Yellow 83, CI Pigment Yellow 93, CI Pigment Yellow 95, CI Pigment Yellow 97, CI Pigment Yellow 98, CI Pigment Yellow 100, CI Pigment Yellow 101, CI Pigment CI Yellow 104, CI Pigment Yellow 106, CI Pigment Yellow 108, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 113, CI Pigment Yellow 114, CI Pigment Yellow 116, CI Pigment Yellow 117, CI Pigment Yellow 119, CI Pigment Yellow 120, CI Pigment Yellow 126, CI Pigment Yellow 127, CI Pigment Yellow 128, CI Pigment Yellow 129, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 150, CI Pigment Yellow 151, CI Pigment Yellow 152, CI Pigment Yellow 153, CI Pigment Yellow 154, CI Pigment Yellow 155, CI Pigment Yellow 156, CI Pigment Yellow 166, CI Pigment Yellow 168, CI Pigment Yellow 175; CI Pigment Orange 1, CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment Orange 36, CI Pigment Orange 38, CI Pigment Orange 40, CI Pigment Orange 43, CI Pigment Orange 46, CI Pigment Orange 49, CI Pigment Orange 51, CI Pigment Orange 61, CI Pigment Orange 63, CI Pigment Orange 64, CI Pigment Orange 71, CI Pigment Orange 73; CI Pigment Violet 1, CI Pigment Violet 19, CI Pigment Violet 23, CI Pigment Bar Olet 29, CI Pigment Violet 32, CI Pigment Violet 36, CI Pigment Violet 38; CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 14, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 19, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 30, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 3 CI Pigment Red 38, CI Pigment Red 40, CI Pigment Red 41, CI Pigment Red 42, CI Pigment Red 48: 1, CI Pigment Red 48: 2, CI Pigment Red 48: 3, CI Pigment Red 48: 4, CI CI Pigment Red 49: 1, CI Pigment Red 49: 2, CI Pigment Red 50: 1, CI Pigment Red 52: 1, CI Pigment Red 53: 1, CI Pigment Red 57, CI Pigment Red 57: 1, CI Pigment Red 57 : 2, CI Pigment Red 58: 2, CI Pigment Red 58: 4, CI Pigment Red 60: 1, CI Pigment Red 63: 1, CI Pigment Red 63: 2, CI Pigment Red 64: 1, CI Pigment Red 81: 1, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Tread 90: 1, CI Pigment Red 97, CI Pigment Red 101, CI Pigment Red 102, CI Pigment Red 104, CI Pigment Red 105, CI Pigment Red 106, CI Pigment Red 108, CI Pigment Red 112, CI Pigment Red 113, CI Pigment Red 114, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 151, CI Pigment Red 166, CI Pigment Red 168, CI Pigment Red 170, CI Pigment Red 171, CI Pigment Red 172, CI Pigment Red 174, CI Pigment Red 175, CI Pigment Red 176, CI Pigment Red 177, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 180, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 188, CI Pigment Red 190, CI Pigment Red 193, CI Pigment Red 194, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 220, CI Pigment Red 224, CI Pigment Red 226, CI Pigment Red 242, CI Pigment Red 243, CI Pigment Red 245, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red 264, CI Pigment Red 265 CI Pigment Blue 15, CI Pigment Blue 15: 3, CI Pigment Blue 15: 4, CI Pigment Blue 15: 6, CI Pigment Blue 60; CI Pigment Green 7, CI Pigment Green 36; CI Pigment Brown 23, CI Pigment Brown 25 CI pigment black 1, pigment black 7.
In particular, C.I. I. Pigment red 177, 254, C.I. I. Pigment red 5, C.I. I. Pigment red 12, C.I. I. Pigment green 36, 7, C.I. I. Pigment blue 209, 15: 6, C.I. I. Pigment blue 16, C.I. I. Pigment Yellow 138, 150 and the like are preferably used.

Furthermore, the following are mentioned according to the classification of the pigment.
Examples of black pigments include carbon black, copper oxide, manganese dioxide, aniline black, and activated carbon.
Yellow pigments include yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa yellow G, Hansa yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline There are yellow rake, permanent yellow NCG, tartrage rake and so on.
Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GK and the like.
Examples of red pigments include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risor red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, There are Alizarin Lake and Brilliant Carmine 3B.
Examples of purple pigments include manganese purple, first violet B, and methyl violet lake.
Examples of blue pigments include bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, first sky blue, and indanthrene blue BC.
Examples of green pigments include chrome green, chromium oxide, pigment green B, malachite green lake, final yellow green G, and the like.
Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.
These color materials can be used alone or in combination.

[Color filter material (ink) medium]
When the color filter material is an ink that is applied to the ink jet method and the ink is a water-based ink, the aqueous medium in the ink is a mixed solvent of water and a water-soluble organic solvent, and the water-soluble organic solvent is a dried ink. It is desirable to use water having a preventive effect, and to use deionized water rather than general water containing various ions.
Specific examples of the water-soluble organic solvent include alkyls having 1 to 5 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, and n-pentanol. Alcohols; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketoalcohols such as acetone and diacetone alcohol; Ethers such as tetrahydrofuran and dioxane; Diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene Oxyethylene or oxypropylene copolymers such as glycol, polyethylene glycol, polypropylene glycol; ethylene glycol, propylene glycol, trimethylene glycol Alkylene glycols wherein the alkylene group contains 2 to 6 carbon atoms, such as triethylene glycol, 1,2,6-hexanetriol; glycerin; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, Lower alkyl ethers such as triethylene glycol monomethyl (or ethyl) ether; lower dialkyl ethers of polyhydric alcohols such as triethylene glycol dimethyl (or ethyl) ether and tetraethylene glycol dimethyl (or ethyl) ether; monoethanolamine; Alkanolamines such as diethanolamine and triethanolamine; sulfolane, N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc. Can be mentioned.
These water-soluble organic solvents can be used alone or as a mixture.
In addition to the above-described components, surfactants, antifoaming agents, preservatives, fungicides, and the like can be added as necessary, and commercially available water-soluble dyes can also be added.
Specifically, anionic surfactants such as fatty acid salts, higher alcohol sulfates, liquid fatty oil sulfates, alkylallylsulfonates, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxy Nonionic surfactants such as ethylene sorbitan alkyl esters, acetylene alcohol, acetylene glycol and the like can be mentioned, and these can be used alone or in combination.
As a color filter material (ink) composed mainly of a monomer, a material having a viscosity that can be ejected by inkjet is selected and used without using a solvent.

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

[Information display panel board]
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 the color filter of the present invention is disposed on this transparent substrate. As this transparent substrate, a material having high visible light transmittance and good heat resistance is suitable. The substrate on the side where the color filter is not disposed may be transparent or opaque.
Examples of substrate materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyethylene (PE), polycarbonate (PC), polyimide (PI), polymer sheets such as acrylic resin, Examples thereof include a flexible material such as a metal sheet. In addition, a composite resin substrate obtained by mixing a filler with a polymer material can be used as necessary. Note that as the actual substrate, a transparent material or an opaque material can be appropriately selected as the display surface side substrate and the back surface side substrate according to each application. 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. It is inconvenient when the information display panel can be rolled, bent or bent.
In the information display panel of the present invention, the present invention is more suitable for a flexible information display panel in which the substrate is made of a flexible material such as a resin by defining the physical characteristics of the color filter. Can be applied to.

[Information display panel electrode]
Electrode forming materials include metals such as aluminum, silver, nickel, copper, gold, and conductive materials such as indium tin oxide (ITO), indium oxide, antimony tin oxide (ATO), conductive tin oxide, and conductive zinc oxide. Examples thereof include conductive polymers such as metal oxides, 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.

[Panel bulkhead for information display]
The shape of the partition provided on the substrate is appropriately set according to the type of display medium involved in display, the shape and arrangement of the electrodes to be arranged, and is not generally limited. However, the width of the partition is 2 to 100 μm, preferably 3 The height of the partition wall is adjusted to 10 to 100 μm, preferably 10 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. 7, 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 substrate plane direction. 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 state 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 an information display panel mounted as a display device on the information display device with a writing function of the present invention, and among these, a photolithography method using a resist film and a mold transfer method are suitable. Used for.

[Color filter opening]
The planar shape of the opening may be any of a circle, an ellipse, a square, and a stripe. However, when the color filter material is arranged as an ink by the ink jet method, the surface tension of the ink is taken into consideration, such as a rectangle. In some cases, it is preferable to round the corners.

[Display medium: Powdered fluid composed of colored particles for display]
Next, the powder fluid used as the display medium in the present invention will be described. As for the name of the powder fluid used in the present invention, the present applicant has obtained the right of “Electronic Powder Fluid (registered trademark): Registration No. 4636931”.

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

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

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

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

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

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

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

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

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

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

Examples of inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, cadmium orange, titanium yellow, Examples include bitumen, ultramarine blue, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, and aluminum powder.
These pigments and inorganic additives can be used alone or in combination. In addition, white particles for display and black particles for display constituting the display medium used in the present invention can be produced by combining a plurality of the above-described additives. Among these, white pigments such as titanium oxide are preferably used for the display white particles, and black pigments such as carbon black are preferably used for the display black particles.
Colored particles for display having a desired color can be produced by blending the colorant.

  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. 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, 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 the d (0.5) of the particles having the minimum diameter to the 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, put particles into a nitrogen stream and use the attached analysis software (software based on volume-based distribution using Mie theory). The diameter and particle size distribution can be measured.

Furthermore, when applying a display medium such as a particle group composed of colored particles for display or a powdered fluid to an information display panel that is driven in the air space, the gas in the void surrounding the display medium between the substrates can be managed. 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.
This gap portion is shown in FIGS. 1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 5A. ), (B), from the portion sandwiched between the opposing substrate 1 and substrate 2, the electrodes 5, 6, the display medium 3, the occupied portions of the color filters 11R, 11G, 11B, the occupied portions of the partition walls 4, the information display panel The gas portion that is in contact with the so-called display medium, excluding the seal portion, is referred to.
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 in a predetermined humidity environment, It is important to apply a sealing material and a sealing method that prevent moisture from entering from the outside.

The distance between the substrates in the information display panel of the present invention is not limited as long as the display medium can be moved and the contrast can be maintained, but is usually adjusted to 10 to 500 μm, preferably 10 to 200 μm.
The volume occupation ratio of the display medium in the space between the opposing substrates is preferably 5 to 70%, more preferably 5 to 60%. When it exceeds 70%, the movement as a display medium is hindered, and when it is less than 5%, the contrast tends to be unclear.
The information display panel using the color filter of the present invention is not limited to the above, and an information display panel of a liquid crystal system, an electrophoresis system, a rotating ball system, or the like can be used.

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

<Manufacture of display panel for driving durability evaluation: 1>
On the ITO film of the transparent glass substrate with the ITO film, a partition (rib) having a matrix-like opening of 50 μm □ is formed with the substrate interval being maintained at 50 μm, and a color filter material is ink-jetted in a region surrounded by the partition A display panel for driving performance evaluation was produced.
In the ink jet method, since it is preferable to control the size of the ink droplets according to the size of the color filter layer forming region as a target, in the embodiment of the present invention, 6 to The color filter material was arranged by using ink droplets controlled to 30 picoliters to form a color filter.
This display panel for evaluation of drivability has a structure in which one color filter material (ink) is arranged in an ink jet system in an area surrounded by all partitions on a substrate, and a black display medium prepared as follows: A white display medium was enclosed in a space surrounded by a partition wall between the substrates so that the volume occupancy ratio of both was 25%.

<Preparation of black particles for display>
The display black particles constituting the black display medium are composed of 60 parts by weight of methyl methacrylate (Kanto Chemical Reagent) and ethylene glycol dimethacrylate as a polyfunctional monomer having a plurality of polymerization reactive groups in one molecule. 40 parts by weight (about 25 mol%) of Togoku (Wako Pure Chemical Reagents), 3 parts by weight of a nigrosine compound (Bontron N07: manufactured by Orient Chemical) as a positively charged charge control agent, and carbon black (special black) as a black pigment 5: 5 parts by weight (made by Degussa) were dispersed by a sand mill, 5 parts by weight of (acrylic and methacrylic) resin-hydrocarbon resin block copolymer (Modipa F600: made by NOF Corporation) were dissolved, and further 2 A solution in which parts by weight of lauryl peroxide (Perroyl L: manufactured by NOF Corporation) was dissolved was used as a surfactant, polyoxyethylene alkyl ether sulfate sodium After suspending, polymerizing, filtering, and drying in purified water to which 0.5% of lithium (Latemul E-118B: manufactured by Kao) was added, it was obtained using a classifier (MDS-2: Nippon Numatic Industries). The black particles for display were positively charged particles having an average particle diameter of about 10 μm.

<Preparation of white particles for display>
The white particles for display constituting the white display medium are negatively charged to 60 parts by weight of styrene monomer (Kanto Chemical Reagent) and 40 parts by weight (about 35 mol%) of divinylbenzene (DVB-960: manufactured by Nippon Steel Chemical Co., Ltd.). Disperse 5 parts by weight of phenol condensate (Bontron E89: manufactured by Orient Chemical Co., Ltd.) as a charge control agent and 20 parts by weight of titanium oxide (Taipeku CR-50: manufactured by Ishihara Sangyo) as a white pigment. Furthermore, a liquid in which 2 parts by weight of lauryl peroxide (Perroyl L: manufactured by NOF Corporation) was dissolved was suspended and purified in purified water to which 0.5% of Latemul E-118B (manufactured by Kao) was added as a surfactant. After filtering and drying, it was obtained using a classifier (MDS-2: Nippon Numatic Kogyo). The white particles for display were negatively charged particles having an average particle size of about 10 μm.

  CI pigment red 177 (R: red), CI pigment green 36 (G: green), CI pigment blue 15: 6 (B: blue) are prepared as color filter materials, and each color filter material is arranged in one color. Three types of display panels for driving performance evaluation were produced, and the display medium was inverted to the three types of display panels for driving performance evaluation to evaluate the driving durability as a display panel.

<Manufacture of display panel for driving durability evaluation: 2>
A partition (rib) having a matrix-like opening of 50 μm □ is formed on the ITO film of a transparent PET substrate with an ITO film, the substrate spacing being maintained at 50 μm, and a color filter material is applied to the region surrounded by the partition Except for forming by the inkjet method, production of a display panel for evaluation of drivability durability: A display panel for evaluation of drivability similar to that shown in 1 was produced, and the same evaluation was performed.

The display panel for driving durability evaluation of the two kinds of substrate materials described above is 100 μm using a color filter material in which each color material shown in Table 1 is blended with the binder shown in the examples and comparative examples shown in Table 2. A total of 30 films are formed on a thick glass plate by an inkjet method to a thickness of 1 μm, and the display condition is repeatedly rewritten (in other words, the display medium is repeatedly reversed and moved). An endurance test was performed to confirm the performance of the display panel with a color filter. Table 1 shows the results of driving durability evaluation. The hardness of the color filter was measured by pencil hardness in addition to the measurement by a Fischer hardness meter (manufactured by Fischer Instruments) corresponding to the surface hardness of the present invention. Table 2 shows the results of pencil hardness evaluation.
In addition, the color filter of each display panel for driving durability evaluation was produced using the color material shown in Table 1 and the photocurable color filter material (ink) containing the binder agent shown in Table 2.

<Preparation of sample panel for evaluation: 3>
As shown in FIG. 8, a photosensitive resin light-shielding layer is provided on the substrate surface of the transparent PET (polyethylene terephthalate resin) substrate 2 on which the predetermined ITO electrode is formed on the side on which the ITO electrode is formed. A light shielding layer was formed by patterning on a bank (black matrix) 13 having a matrix-like opening by known lithography.
Next, each color is arranged such that the red color filter material 11R, the green color filter material 11G, and the blue-purple color filter material 11B form a set in the three adjacent openings in the matrix-shaped openings partitioned by the black matrix 13. The color filter material was arranged by an ink jet method.
CI pigment red 177 (R: red), CI pigment green 36 (G: green), CI pigment blue 15: 6 (B: blue purple) are prepared for the three color filter materials, respectively. The color filter material (ink) was adjusted and each color filter material was arranged by an ink jet method.
In the ink jet method, since it is preferable to control the size of the ink droplets according to the size of the color filter layer forming region that is the target, in the embodiment of the present invention, 6 to The color filter material was arranged by using ink droplets controlled to 30 picoliters to form a color filter.
An evaluation sample shown in FIG. 8 is obtained by providing a cell-forming partition wall having a height of 40 μm and a width of 15 μm on a PET substrate on which an electrode and a color filter are formed and bonding the other PET substrate as a counter substrate. Panel 17 was obtained.

<Evaluation of tensile modulus and elongation at break of color filter>
First, using a color filter material, an evaluation sample piece having a width of 10 mm, a length of 70 mm, and a thickness of 10 μm (a sample piece 15 for evaluation of a color filter material used for the color filters (11R, 11G, and 11B) shown in FIG. 9) Was made. For this sample piece for evaluation, as shown in FIG. 9, using an evaluation apparatus with a sample piece fixing jig 16 (Rheometer RT-3010D-CW manufactured by Rheotech Co., Ltd.), both ends of the evaluation sample piece are pulled 10 mm each. The sample was chucked with a jig of a machine, a tensile test was performed, and the tensile elastic modulus and elongation at break were determined from the results.

<Evaluation of sample panel for evaluation>
The prepared sample panel was subjected to a bending test to evaluate the state of the color filter.
As shown in FIG. 10, this evaluation is performed 10 times by repeating a bending test consisting of a process of pressing the sample panel 17 for evaluation against a cylindrical fixture 14 having a diameter of 20 mm, bending it to an angle of 90 °, and returning it to the original state 10 times. The appearance around the color filter including the color filter after the repetition was observed with a microscope. The evaluation results are shown in Table 3. The evaluation sample panel 17 was evaluated by arranging a color filter made of a color filter material having characteristics obtained by combining various tensile elastic moduli and elongation at break as shown in Table 3.

An information display panel using the color filter of the present invention includes 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, a handy terminal, an electronic book, and an electronic newspaper. Electronic paper, signboards, posters, bulletin boards such as blackboards and whiteboards, electronic desk calculators, display units for home appliances, automotive products, card display units such as point cards and IC cards, electronic advertisements, information boards, electronic POPs (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 Used.
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.

(A), (b) is a figure which shows the fundamental structure of the information display panel of this invention. (A), (b) is a figure which shows the example of 1 structure of the information display panel of this invention. (A), (b) is a figure which shows the other structural example of the information display panel of this invention. (A), (b) is a figure which shows the other structural example of the information display panel of this invention. (A), (b) is a figure which shows the other structural example of the information display panel of this invention. (A)-(h) is a figure for demonstrating the manufacturing method of the color filter of this invention. It is a figure which shows an example of the shape of the partition in the information display panel of this invention. It is a figure which shows the structure of the sample panel for color filter evaluation of the Example of this invention. It is a figure for demonstrating the tension test performed with respect to the sample piece for evaluation of the color filter of the Example of this invention. It is a figure for demonstrating the bending test performed with respect to the sample panel for color filter evaluation of the Example of this invention.

Explanation of symbols

1 Substrate (Back side substrate)
2 Substrate (Display side transparent substrate)
3 Display media (particle group, powder fluid)
3W White display medium 3B Black display medium 3Wa White particles for display 3Ba Black particles for display 4 Partition 5 Electrode 6 Transparent electrode 11R Red color filter 11G Green color filter 11B Blue-violet color filter 12B Black plate 12W White plate 13 Black matrix (bank)
14 Cylinder fixing jig 15 Sample piece for evaluation 16 Sample piece fixing jig 17 Sample panel for evaluation

Claims (9)

In a color filter for a display panel in which a color filter material containing at least a color material and a binder resin is cured,
It is made of a color filter material having a hardness of 300 [mN / mm ² ] or more measured when it is deformed by 10% by applying pressure with a pressing needle having a pyramid-shaped minute tip on the surface after curing. Color filter for display panel. In a color filter for a display panel in which a color filter material containing at least a color material and a binder resin is cured,
A color filter for a display panel, comprising a color filter material whose surface after curing has a pencil hardness of H or more.   The display panel color filter according to claim 1, wherein the binder resin contains a photocurable resin. In a color filter for a display panel in which a color filter material containing at least a color material and a binder resin is cured,
A color filter for a display panel, having a tensile elastic modulus of 10 to 100 MPa and an elongation at break of 2 to 500%.   The color filter for a display panel according to claim 4, wherein the tensile elastic modulus is 20 to 60 MPa and the elongation at break is 2 to 200%.   The color filter for a display panel according to any one of claims 1 to 5, wherein the color filter is produced using an inkjet method.   A transparent and flexible resin substrate on which the display panel color filter according to any one of claims 1 to 6 is formed, and the other flexible substrate as constituent members. Information display panel. An information display panel that displays information such as an image by enclosing a display medium in a space partitioned by a partition between at least one transparent substrate and moving the display medium by an electric field,
7. The display panel color filter according to claim 1 is used as a color filter of three primary colors (R: red, G: green, B: bluish purple) to perform color display. An information display panel.   The display medium driven by the electric field is composed of colored particles for display having chargeability and optical reflectance, and the state once displayed is maintained until the next display rewriting operation. The information display panel according to claim 8, wherein the display panel is an information display panel.

Images