JP2018022063A - Color filter and reflective display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce deviation in a view angle relating to a color difference in a color filter.SOLUTION: A color filter layer 17 includes: a first filter part 17X in which a first colored layer 17c, a second colored layer 17m and a third colored layer 17y having different transmission wavelength regions from one another and extending in one direction, with the longitudinal direction of each colored layer aligned in an X direction on an arrangement surface, are arranged in a Y direction that intersects the X direction; and a second filter part 17Y adjoining to the first filter part 17X, in which the first colored layer 17c, the second colored layer 17m and the third colored layer 17y are arranged in the X direction, with the longitudinal direction of each colored layer aligned to the Y direction on the arrangement surface.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a color filter and a reflective display device.

As a display device, a transmission type or a reflection type comprising a display unit capable of changing the transmittance or the reflectance for each display unit, and a color filter in which a colored layer is arranged to face each display unit of the display unit. Display devices are known.
For example, a transmissive liquid crystal display device using a backlight is known as a transmissive display device. The transmissive liquid crystal display device is not suitable for applications in which the user directly sees the light transmitted through the color filter, which places a heavy burden on the user's eyes and allows the user to look at the display screen for a long time .
In contrast, the reflective display device performs color display by reflecting external light such as natural light incident on the color filter by a reflective display unit facing the color filter. For this reason, the reflective display device is less burdensome on the user's eyes than the transmissive display device, and is more suitable for the work of the user looking at the display screen for a long time. A reflective display device can be configured without a built-in display light source, and thus consumes less power.
As an example of the reflective display device, for example, a device including a reflective display unit such as an electrophoretic method or a twist ball method has been proposed. Such a reflective display device is attracting attention as a display device close to a paper display medium because it displays characters and images by reflected light of external light in the same manner as a printed paper surface.

For example, in Patent Document 1, in a multicolor display panel in which a display body including particles that move or rotate by applying an electric field is disposed between a pair of substrates, at least one of which is transparent, at least one of the pair of substrates is transparent. A multicolor display panel in which a color filter is formed on a substrate has been proposed.
In Patent Document 1, as a configuration of a color filter, a configuration in which three colored layers of square shapes colored in three primary colors are arranged in a square lattice pattern, and a striped colored color in three primary colors and extending in one direction are provided. And an arrangement in which the layers are arranged.

JP 2003-161964 A

However, the conventional color filter and reflective display device as described above have the following problems.
In a reflective display device, when the color filter has a configuration in which three square colored layers colored in the three primary colors are arranged in a square lattice pattern (hereinafter referred to as a square lattice arrangement), the unit pixel has three primary colors. These three colored layers and a non-colored layer. Since the non-colored layer can reflect external light that does not pass through the colored layer, a bright display screen can be obtained. However, in the unit pixel, since the area occupied by the colored layer is reduced by the amount of the non-colored layer, there is a problem that the saturation of the display color is deteriorated.
On the other hand, when the color filter has a configuration in which elongated colored layers colored in the three primary colors are arranged in stripes (hereinafter referred to as stripe arrangement), although the brightness is reduced, The relative area increases. For this reason, in the stripe arrangement, it is possible to display higher saturation than in the square lattice arrangement, and to perform high-quality color display.

However, in the case of the stripe arrangement, there is a problem that the viewing angle size in which the display color characteristics such as color difference are within an allowable range differs between the longitudinal direction of each colored layer and the direction orthogonal thereto. That is, a cross section that includes the normal line of the display screen and is cut in parallel with each colored layer in the longitudinal direction (where the viewing angle is large, whereas the cross section that includes the normal line of the display screen and is orthogonal to the longitudinal direction of each colored layer) Then, the viewing angle becomes small.
That is, depending on the direction in which the display screen is viewed, there is a problem that the color difference increases and the color reproducibility deteriorates.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a color filter and a reflective display device that can reduce the deviation of the viewing angle related to the color difference.

  In order to solve the above-described problem, the color filter according to the first aspect of the present invention includes a plurality of colored layers having different transmission wavelength bands and extending long in one direction, the first longitudinal direction of each of the colored layers on the arrangement surface. A first filter portion arranged in a second direction intersecting the first direction in a state aligned with the first direction, and disposed adjacent to the first filter portion, wherein the plurality of colored layers are And a second filter section arranged in the first direction in a state in which the respective longitudinal directions are aligned with the second direction on the arrangement surface.

  In the color filter, the plurality of colored layers in the first filter portion and the second filter portion may be colored in mutually different colors.

  In the color filter, a plurality of the first filter units and the second filter units are provided, and the first filter unit and the second filter unit may be alternately arranged adjacent to each other in the first direction and the second direction. Good.

  In the color filter, the first direction and the second direction may be orthogonal to each other.

  The reflective display device according to the second aspect of the present invention is disposed to face the color filter and the plurality of colored layers in the first filter portion and the second filter portion of the color filter, respectively. A plurality of reflective display units whose reflectance can be changed independently.

  In the reflective display device, the first filter unit and the second filter unit may be arranged in units of pixels which are color display units in the plurality of reflective display units.

  In the reflective display device, at least one of the first filter unit and the second filter unit is arranged in units of a pixel group in which a plurality of pixels which are color display units in the plurality of reflective display units are adjacent to each other. May be.

  In the reflective display device, the first filter portion and the second filter portion may be formed with a non-colored region facing at least one of the reflective display portions in the pixel. Good.

  The reflection type display device may further include a light transmission layer disposed between the color filter and the plurality of reflection type display units.

  According to the color filter and the reflective display device of the present invention, there is an effect that it is possible to reduce the deviation of the viewing angle related to the color difference.

It is a typical longitudinal section showing the composition of the principal part of the reflection type display of a 1st embodiment of the present invention. FIG. 3 is a schematic plan view illustrating an arrangement of color filters according to the first embodiment of the present invention. It is a schematic diagram explaining the effect | action of the color filter and reflection type display apparatus of the 1st Embodiment of this invention. It is a schematic diagram explaining the effect | action of the color filter and reflection type display apparatus of the 1st Embodiment of this invention. It is a typical top view which shows the structure of the principal part of the reflection type display apparatus of the modification (1st modification) of the 1st Embodiment of this invention. It is a typical top view which shows the structure of the principal part of the reflection type display apparatus of the modification (2nd modification) of the 1st Embodiment of this invention. It is a typical top view which shows the structure of the principal part of the reflection type display apparatus of the modification (3rd modification) of the 1st Embodiment of this invention. It is a typical top view which shows the structure of the principal part of the reflection type display apparatus of the modification (4th modification) of the 1st Embodiment of this invention. It is a typical top view which shows the structure of the principal part of the reflection type display apparatus of the 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
A color filter and a reflective display device according to a first embodiment of the present invention will be described.
FIG. 1 is a schematic longitudinal sectional view showing a configuration of a main part of the reflective display device according to the first embodiment of the present invention. FIG. 2 is a schematic plan view showing the arrangement of the color filters according to the first embodiment of the present invention.

As shown in FIG. 1, the reflective display panel 1 (reflective display device) of the present embodiment includes a substrate 10, a first electrode layer 11, an adhesive layer 12, and a reflective display layer 13 (a plurality of reflective display layers 13). The reflective display portion), the second electrode layer 14, the substrate 15, the ink fixing layer 16, the color filter layer 17 (color filter), and the protective layer 18 are laminated in this order.
The reflective display panel 1 divides incident light from the outside into three colors of a first color, a second color, and a third color by a color filter layer 17 and is driven by a reflective display layer 13 driven based on an image signal. This is a reflective display device capable of displaying a full color image by adjusting the amount of reflected light of three colors.

The substrate 10 is composed of a plate-like insulator. For example, glass or the like may be used as the material of the substrate 10.
A first electrode layer 11 is laminated on the surface of the substrate 10.

The first electrode layer 11 applies to the reflective display layer 13 a driving voltage that changes the reflectance of the reflective display layer 13 described later. In the present embodiment, the first electrode layer 11 is patterned corresponding to the shape and arrangement of the sub-pixels so that a voltage can be applied to each sub-pixel in the pixel that is a display unit.
The first electrode layer 11 is a drive electrode for applying a drive voltage for driving a reflective display layer 13 described later in order to control the gradation of the first color, the second color, and the third color in each pixel. . The first electrode layer 11 includes a plurality of first-color subpixel electrodes 11c, second-color subpixel electrodes 11m, and third-color subpixel electrodes 11y. Hereinafter, for simplicity, the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y may be collectively referred to as each drive electrode or each sub-pixel electrode. .
The first electrode layer 11 may be formed of, for example, a conductive oxide having transparency such as indium oxide such as ITO, tin oxide, or zinc oxide, or a carbon nanotube or a thiophene compound. .

A reflective display layer 13 is laminated on the first electrode layer 11 with an adhesive layer 12 interposed.
The material of the adhesive layer 12 is not particularly limited as long as the first electrode layer 11 and the surface 13b of the reflective display layer 13 can be adhered to each other.

The reflective display layer 13 has an appropriate layer structure that can switch and display at least white and black by applying an electric field in the layer thickness direction.
In the present embodiment, the reflective display layer 13 has a configuration in which the reflectance gradually changes from the minimum value (black) to the maximum value (white) according to the magnitude of the electric field. Therefore, the reflective display layer 13 can express black and white gradation.
The reflectance of the reflective display layer 13 may be changed on the surface 13a opposite to the surface 13b.
For example, the reflective display layer 13 may have a structure selected from a reflective liquid crystal system, a cholestic liquid crystal system, an electrophoretic system (such as a microcapsule system), a microcup system, and an electrochromic system.

The second electrode layer 14 is a transparent electrode laminated on the surface 13 a of the reflective display layer 13.
In the present embodiment, the second electrode layer 14 is disposed in a range that covers the entire first electrode layer 11.
Each drive electrode in the first electrode layer 11 and the second electrode layer 14 are connected to a drive power supply (not shown) via a switching element (not shown). For this reason, when the switching element is driven in accordance with the image signal, an electric field is generated between each drive electrode and the second electrode layer 14 by a drive voltage in accordance with the image signal.
As a material of the second electrode layer 14, for example, a conductive transparent material such as indium tin oxide (ITO) may be used.

The substrate 15 is a light transmissive layered portion laminated on the second electrode layer 14.
As a material of the base material 15, for example, a glass base material may be used. As a material of the base material 15, for example, a film base material such as a PET (polyethylene terephthalate) film or a PEN (polyethylene naphthalate) film may be used.

The ink fixing layer 16 is a light-transmitting layered portion formed to fix a color filter layer 17 to be described later on the base material 15. In the present embodiment, an example in which the reflective display panel 1 includes the ink fixing layer 16 will be described. However, when the color filter layer 17 described later is directly formed on the substrate 15, the ink fixing layer 16 is omitted. May be.
The ink fixing layer 16 is laminated on the surface 15 a opposite to the surface in contact with the second electrode layer 14 in the base material 15.
As the material of the ink fixing layer 16, an appropriate material is used according to the material of the base material 15 and a color filter layer 17 described later.
Examples of the material of the ink fixing layer 16 include urethane resin, polyester resin, acrylic resin, vinyl alcohol resin, and the like.
The ink fixing layer 16 may contain a porous material such as synthetic silica or alumina in order to enhance the solvent absorbability of each ink forming the color filter layer 17 described later.

The method for forming the ink fixing layer 16 is not particularly limited.
For example, the ink fixing layer 16 may be formed by applying an ink fixing layer forming coating liquid on the substrate 15 and then drying the ink fixing layer 16 to form the ink fixing layer 16.
When the ink fixing layer 16 is formed by sheet processing, the ink fixing layer forming coating liquid may be applied by, for example, screen printing, offset printing, spin coating, and intermittent coating with a die. Good.
When the ink fixing layer 16 is formed by continuous processing by roll-to-roll, the ink fixing layer forming coating liquid may be applied by, for example, die coating, comma coating, curtain coating, gravure coating, or the like.

As a method for drying the ink fixing layer forming coating liquid coated on the base material 15, for example, heating, blowing, decompressing, or the like may be used.
As will be described later, in this embodiment, after the first electrode layer 11, the adhesive layer 12, the reflective display layer 13, the second electrode layer 14, and the base material 15 are laminated on the substrate 10, ink fixing is performed. Layer 16 is formed. The drying process of the ink fixing layer forming coating liquid is performed in a temperature environment that does not cause thermal deformation beyond the allowable range in each of these layers. For example, when a thermoplastic resin film is used for at least one of the substrate 10 and the base material 15, it is more preferable that the drying process is performed at a temperature equal to or lower than the glass transition point of the thermoplastic resin film.

The color filter layer 17 is laminated on the surface 16 a of the ink fixing layer 16.
The color filter layer 17 includes a plurality of first colored layers 17c, second colored layers 17m, and third colored layers 17y.
The first colored layer 17c has a transmission wavelength band that transmits only the wavelength component of the first color. The second colored layer 17m has a transmission wavelength band that transmits only the wavelength component of the second color. The third colored layer 17y has a transmission wavelength band that transmits only the wavelength component of the third color.
The first color, the second color, and the third color are not particularly limited as long as the wavelength bands are different from each other and full color display is possible by a combination thereof.
The combination of the first color, the second color, and the third color is preferably selected so that the transmitted light of each color becomes white light.
For example, the first color, the second color, and the third color may be red, green, and blue.
For example, the first color, the second color, and the third color may be cyan, magenta, and yellow.
Hereinafter, for the sake of simplicity, the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y may be collectively referred to as each colored layer.

The first colored layer 17c, the second colored layer 17m, and the third colored layer 17y sandwich the reflective display layer 13 between the first color subpixel electrode 11c, the second color subpixel electrode 11m, and the first color layer 17y. The three-color sub-pixel electrodes 11y are disposed so as to face each other.
In the present embodiment, each colored layer and the surface 13a of the reflective display layer 13 are separated by a light transmission layer 19 in which a second electrode layer 14, a base material 15, and an ink fixing layer 16 are laminated. .
The light transmission layer 19 can transmit light of the first color, the second color, and the third color satisfactorily.

The distance between the color filter layer 17 and the reflective display layer 13 (the thickness of the light transmission layer 19) is preferably as short as possible in order to improve the viewing angle characteristics described later.
For example, the thickness of the light transmission layer 19 may be an optical distance (optical path length) of 5 μm or more and 200 μm or less. The thickness of the light transmission layer 19 is more preferably 10 μm or more and 150 μm or less in terms of optical distance.

Next, an arrangement pattern in plan view of the first electrode layer 11 and the color filter layer 17 will be described.
FIG. 2 is a schematic plan view showing a part of the reflective display panel 1 with the protective layer 18 omitted. 2 is a cross section similar to that obtained by removing the protective layer 18 in FIG.

As shown in FIG. 2, the outer shapes of the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y in plan view are all rectangular extending in one direction. Shape. The long widths and short widths of the first color subpixel electrode 11c, the second color subpixel electrode 11m, and the third color subpixel electrode 11y may be different from each other. However, FIG. 2 shows an example in which the long widths and short widths of the first color subpixel electrode 11c, the second color subpixel electrode 11m, and the third color subpixel electrode 11y are equal to each other. It is shown in the figure.
However, each subpixel electrode may have a pseudo-rectangular shape in which a concave portion or a convex portion is formed in a part of a rectangle depending on the arrangement position of the switching element, for example.
Whether it is a rectangular shape or a pseudo-rectangular shape, each subpixel electrode can be distinguished from a longitudinal direction representing the entire extending direction and a short direction perpendicular thereto.

  As schematically shown in FIG. 2, the outer shapes in plan view of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y are all rectangular shapes that extend long in one direction. Each longitudinal width and each lateral width in the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y may be different from each other. However, FIG. 2 illustrates an example in which the longitudinal widths and the lateral widths of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y are equal to each other.

  The outline in plan view of the first color sub-pixel electrode 11c (second color sub-pixel electrode 11m, third color sub-pixel electrode 11y) and the first colored layer 17c (second colored layer 17m, third colored layer) 17y) may be the same or different from each other in plan view. However, it is preferable that the opposing areas are as wide as possible when the respective longitudinal directions are opposed to each other.

In the present embodiment, a first color sub-pixel electrode 11c, a second color sub-pixel electrode 11m, and a third color sub-pixel are arranged in a rectangular area partitioned in the X direction and the Y direction on the substrate 10. A first pixel P _EX and a second pixel P _EY are configured in which the electrodes 11y are aligned in the longitudinal direction and are arranged one by one in each _lateral direction.
The first pixel P _EX and the second pixel P _EY are color display units for performing full color display according to the image signal, and are an electrode group of the minimum unit for applying a driving voltage to the reflective display layer 13. Is included.

In the first pixel P _EX, the first color sub-pixel electrode 11c, the right X direction (the left of each longitudinal direction shown in the second color sub-pixel electrodes 11m, and third color sub-pixel electrode 11y Extending in the first direction).
In the second pixel _PEY , the longitudinal direction of each of the first color subpixel electrode 11c, the second color subpixel electrode 11m, and the third color subpixel electrode 11y is a Y direction orthogonal to the X direction shown in the drawing ( It extends in the direction from the top to the bottom in the figure, the second direction).
The first pixel P _EX and the second pixel P _EY are arranged within a rectangular region having the same shape. The rectangular area may be a rectangle or a square, but the length in the X direction and the length in the Y direction are constant in the reflective display panel 1. FIG. 2 shows an example where the rectangular area is a square as an example.

In each first pixel P _EX and each second pixel P _EY , the area occupied by the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y is as follows: Although it may differ for every color, in this embodiment, it is mutually equal as an example. Each sub-pixel electrode can apply a driving voltage for driving the rectangular region of the reflective display layer 13 facing the first pixel P _EX (second pixel P _EY ) into three equal parts. Yes.

A plurality of first pixels P _EX and second pixels P _EY are provided. FIG. 2 shows a part of the reflective display panel 1 in plan view. The number and size of the first pixel P _EX and the second pixel P _EY are appropriately set according to the required display screen size and display resolution.
Each of the first pixels P _EX and each of the second pixels P _EY are arranged in a rectangular lattice pattern with a constant pitch in the X direction and the Y direction. In each of the X direction and the Y direction, the first pixels P _EX and the second pixels P _EY are alternately arranged.

In the rectangular region partitioned in the X direction and the Y direction on the ink fixing layer 16, the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y are aligned in the longitudinal direction. A first filter unit 17X and a second filter unit 17Y arranged one by one in each short direction are configured.
In the first filter portion 17X, the longitudinal directions of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y extend in the X direction shown in the drawing.
In the second filter portion 17Y, the longitudinal directions of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y extend in the Y direction shown in the drawing.
In the present embodiment, the same number of first filter portions 17X and second filter portions 17Y as the first pixels P _EX and the second pixels P _EY are formed.
Each first filter unit 17X (each second filter unit 17Y) is disposed in a range overlapping with each first pixel P _EX (each second pixel P _EY ).

In each first filter portion 17X (each second filter portion 17Y), the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y are respectively a first color sub-pixel electrode 11c and a second colored layer 17y. The color subpixel electrode 11m and the third color subpixel electrode 11y are arranged so as to overlap.
In the present embodiment, the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y are respectively the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel. The pixel electrodes 11y are arranged so as to overlap each other inside the drive voltage application range.

The area ratio of the colored portion occupied by the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y in the rectangular region of the first pixel P _EX (second pixel P _EY ) is 25% or more and 100%. It may be the following.
When the area ratio of the colored portion is less than 25%, the amount of light transmitted through the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y decreases, so that vividness (saturation) at the time of color display is achieved. May be too low.
The higher the colored portion area ratio, the better. However, when the colored portion area ratio is close to 100%, depending on the method of manufacturing the color filter layer 17, color mixing is likely to occur in adjacent colored layers. For this reason, it is more preferable that the colored portion area ratio is a colored portion area ratio at which color mixing does not occur in the manufacturing process. For example, when the color filter layer 17 is formed by the ink jet printing method, the area ratio may be 99% or less.

As described above, each first filter unit 17X and each second filter unit 17Y is similar to each first pixel P _EX and each second pixel P _EY in the X direction and the Y direction. Each is arranged in a lattice at a constant pitch. In each of the X direction and the Y direction, the first filter unit 17X and the second filter unit 17Y are alternately arranged.

  The color filter layer 17 may be formed by a method of patterning a colored resist film by photolithography, for example, as is done in a color filter for a transmissive liquid crystal display device. In this case, the color filter layer 17 can be formed directly on the substrate 15 without providing the ink fixing layer 16.

The color filter layer 17 may be formed by, for example, applying and solidifying ink corresponding to the color of each colored layer on the surface 16a that is the arrangement surface of each colored layer.
In this case, the color filter layer 17 is formed without forming a black matrix by separately applying the ink to the formation regions of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y. It is formed. Since the color filter layer 17 eliminates the light amount loss due to the black matrix, the transmitted light amount of the color filter layer 17 is further improved.

When the color filter layer 17 is formed by ink application, an appropriate ink application method capable of separately applying ink is used as the ink application method.
Examples of ink application methods suitable for forming the color filter layer 17 include screen printing, offset printing, and ink jet printing. In particular, the ink jet printing method is more preferable in that the position of the arrangement position of the color filter layer 17 with respect to the first electrode layer 11 becomes easier and the productivity is high.
Examples of the method for solidifying the ink after coating on the ink fixing layer 16 include a method of drying by heating, air blowing, reduced pressure or the like. For example, when the ink is an energy ray curable ink such as UV ink, a method of irradiating energy rays such as UV light may be used.
In particular, when UV ink is used, the color filter layer 17 can be formed even if UV ink is directly applied to the surface of the substrate 15 without providing the ink fixing layer 16.

Below, the manufacturing method and ink in the case of forming the color filter layer 17 by the inkjet printing method will be described in detail.
As an ink jet apparatus used for the ink jet printing method, there are a piezo conversion method and a heat conversion method depending on a difference in an ink discharge method, and it is more preferable to use a piezo conversion ink jet device.
The ink atomization frequency of the ink jet apparatus may be 5 kHz or more and 100 kHz or less.
The nozzle diameter of the inkjet apparatus may be 5 μm or more and 80 μm or less.
More preferably, the ink jet apparatus includes a plurality of ink jet heads, and about 60 to 500 nozzles are incorporated in one ink jet head.

  As the ink for forming the color filter layer 17 (hereinafter simply referred to as ink), for example, a configuration in which a colorant, a solvent, a binder resin, and a dispersant are mixed may be used.

  As the colorant contained in the ink, all pigments can be used regardless of organic pigments, inorganic pigments, dyes and the like. As the colorant, organic pigments are more preferable, and those having excellent light resistance are more preferable.

Specific examples of the colorant include C.I. I. Pigment Red 9, 19, 38, 43, 97, 122, 123, 144, 149, 166, 168, 177, 179, 180, 192, 208, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 254, Pigment Blue 15, 15: 3, 15: 6, 16, 22, 29, 60, 64, C.I. I. Pigment Green 7, 36, 56, 58, 59, C.I. I. Pigment Yellow 20, 24, 86, 81, 83, 93, 108, 109, 110, 117, 125, 137, 138, 139, 147, 148, 150, 153, 154, 166, 168, 185, C.I. I. Pigment Orange 36, 73, C.I. I. Pigment Violet 23 and the like.
Two or more kinds of materials may be mixed in the colorant so as to obtain a necessary hue.

As a solvent contained in the ink, a solvent having a surface tension of 35 mN / m or less and a boiling point of 130 ° C. or more may be used in consideration of suitability for ink jet printing.
If the surface tension of the ink is greater than 35 mN / m, the stability of the dot shape during ink ejection may be impaired.
If the boiling point of the ink is less than 130 ° C., the drying property in the vicinity of the nozzle may be remarkably increased. This may cause nozzle clogging and the like.

Specific examples of the solvent include, for example, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-methoxyethyl acetate, 2-ethoxyethyl ether, 2- (2-Ethoxyethoxy) ethanol, 2- (2-butoxyethoxy) ethanol, 2- (2-ethoxyethoxy) ethyl acetate, 2- (2-butoxyethoxy) ethyl acetate, 2-phenoxyethanol, diethylene glycol dimethyl ether and the like can be mentioned. .
Two or more types of solvents may be mixed and used as necessary.

  Examples of the binder resin contained in the ink include acrylic resins, novolac resins, melamine resins, and epoxy resins. As the binder resin, one kind of resin may be used alone, or two or more kinds may be mixed and used.

Examples of acrylic resins include, for example, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, benzyl (meth) acrylate, lauryl (meth) Alkyl (meth) acrylates such as acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, ethoxyethyl (meth) acrylate, glycidyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, di Examples thereof include a polymer of a monomer (monomer) such as cycloaliphatic (meth) acrylate such as cyclopentenyl (meth) acrylate.
One of these monomers may be used alone, or two or more thereof may be used in combination. Further, a resin copolymerized with a compound such as styrene, cyclohexylmaleimide, phenylmaleimide, cyclohexylmaleimide, phenylmaleimide, methylmaleimide, ethylmaleimide, n-butylmaleimide, laurylmaleimide and the like that can be copolymerized with these acrylates is used. Also good.

An ethylenically unsaturated group may be added to the acrylic resin.
Examples of the method of adding an ethylenically unsaturated group to an acrylic resin include, for example, a method of adding an ethylenically unsaturated group such as acrylic acid and a carboxylic acid-containing compound to an epoxy-containing resin such as glycidyl methacrylate, methacrylic acid And a method of adding an epoxy-containing acrylate such as glycidyl methacrylate to a carboxylic acid-containing resin such as methacryloyloxyethyl isocyanate.

  Examples of novolak resins include phenol novolac epoxy resins and cresol novolac epoxy resins.

Examples of melamine resins include alkylated melamine resins (such as methylated melamine resins and butylated melamine resins), mixed etherified melamine resins, and the like. The melamine resin may be a high condensation type or a low condensation type.
A melamine resin may be used individually by 1 type, and 2 or more types may be mixed and used for it. The melamine resin may be further mixed with an epoxy resin as necessary.

Examples of epoxy resins include, for example, glycerol / polyglycidyl ether, trimethylolpropane / polyglycidyl ether, resorcin / diglycidyl ether, neopentyl glycol / diglycidyl ether, 1,6-hexanediol / diglycidyl ether, ethylene glycol (Polyethylene glycol) and diglycidyl ether.
One type of epoxy resin may be used alone, or two or more types may be mixed and used.

The mass average molecular weight of the binder resin contained in the ink may be in the range of 200 or more and 10,000 or less. The mass average molecular weight of the binder resin is more preferably in the range of 300 or more and 8000 or less.
When the mass average molecular weight of the binder resin exceeds 10,000, the ink fluidity is insufficient during the drying process of the color filter layer 17 and the pattern flatness may be deteriorated.
When the mass average molecular weight of the binder resin is less than 300, physical properties such as solvent resistance and heat resistance may be deteriorated.

The dispersant contained in the ink improves the dispersibility of the pigment in the solvent.
As the dispersant, for example, an ionic surfactant, a nonionic surfactant, or the like may be used.
Specific examples of the dispersant include sodium alkylbenzene sulfonate, poly fatty acid salt, fatty acid salt alkyl phosphate, tetraalkyl ammonium salt, polyoxyethylene alkyl ether and the like. As the dispersant, an organic pigment derivative, polyester, or the like may be used.
One type of dispersant may be used alone, or two or more types of dispersants may be mixed and used.

The viscosity of the ink may be 1 mPa · s or more and 20 mPa · s or less. The viscosity of the ink is more preferably 5 mPa · s or more and 15 mPa · s or less.
When the viscosity of the ink exceeds 20 mPa · s, there is a possibility that the ink does not land at a predetermined position when the ink is ejected or the nozzle is clogged.
If the viscosity of the ink is less than 1 mPa · s, the ink may be easily scattered during ink ejection.

  The mass ratio between the colorant and the binder resin in the ink may be in the range of 1: 9 to 1: 1. The fluidity of the ink is adjusted by changing the amount of the binder resin in the ink. By changing the amount of the binder resin in the ink, the density variation of the colorant in the ink is improved.

  The reflection type display panel is generally used as a display medium using external light. For this reason, the color density of the color filter of the reflective display panel is lower than the color density of the color filter of the transmissive display panel typified by a liquid crystal display so that a bright display screen can be obtained by entering a large amount of external light. Better. As a result, regarding the color gamut, the reflective display panel tends to be narrower than the transmissive display panel.

  When the binder resin exceeds 9 parts by mass with respect to 1 part by mass of the colorant of the ink, there is a possibility that the coating amount for obtaining a necessary color density becomes excessive. Furthermore, the increase in the binder resin increases the viscosity of the ink, resulting in poor ink fluidity. For this reason, the colorant tends to gather at the center of the dots formed by the ink droplets, the color density at the periphery of the dots tends to decrease, and color unevenness of the color filter layer 17 tends to occur.

When the binder resin is less than 1 part by mass with respect to 1 part by mass of the colorant of the ink, the colorant contained in the ink is relatively increased and the color density is increased. For this reason, it is necessary to dilute by increasing the amount of solvent (volatile matter) of the ink, or to form the color filter layer 17 by reducing the ink discharge amount.
For example, when the solvent is increased, the fluidity of the ink is increased and the ink discharge amount is also increased. For this reason, it is easier for the colorant to collect in the peripheral portion of the dot than in the central portion of the dot formed by the ink droplets, the color density at the central portion of the dot is likely to be lowered, and the color unevenness of the color filter layer 17 is caused. It tends to occur.
When the ink discharge amount is small, the dot diameter due to the ink droplets is small, and a gap is likely to be generated between the dots, so that it is difficult to form a good color filter layer 17.

As shown in FIG. 1, the protective layer 18 is a light-transmitting layered portion laminated so as to cover the ink fixing layer 16 and the color filter layer 17. The protective layer 18 protects the color filter layer 17 by covering the color filter layer 17. The protective layer 18 prevents the color filter layer 17 from being damaged by mechanical contact, attached with dirt, or absorbing moisture.
The material of the protective layer 18 is, for example, an organic resin such as polyamide, polyimide, polyurethane, polycarbonate, acrylic or silicone, or an inorganic material such as Si ₃ N ₄ , SiO ₂ , SiO, Al ₂ O ₃ , or Ta ₂ O _3. May be used.
The protective layer 18 can be formed by, for example, spin coating, roll coating, a coating method such as a printing method, or a vapor deposition method after the color filter layer 17 is formed.

Next, the operation of the reflective display panel 1 of the present embodiment will be described focusing on the operation of the color filter layer 17.
FIG. 3 is a schematic diagram for explaining the operation of the color filter and the reflective display device according to the first embodiment of the present invention. FIG. 4 is a schematic diagram for explaining the operation of the color filter and the reflective display device according to the first embodiment of the present invention.

In the reflective display panel 1, when a voltage is applied between the first electrode layer 11 and the second electrode layer 14 in each first pixel P _EX and each second pixel P _EY , Depending on the voltages applied to the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y, the reflective display layer 13 at the portion facing them is appropriately The display can be switched between white, gray and black with reflectivity.

  When all the portions of the reflective display layer 13 facing the drive unit of the first electrode layer 11 are displayed in white, or when only the portions corresponding to the colored portions of the reflective display layer 13 are displayed in white, the hue of the colored portions If the color of the colored portion of the reflective display layer 13 is black, the white color of the non-colored portion is mixed with white or black, and a color similar to the hue of the colored portion is displayed. Since only the reflected light is reflected, white display is performed, and when all the portions of the reflective display layer 13 facing the drive unit of the first electrode layer 11 are displayed in black, all the light is not reflected and black is displayed. Display.

For example, in FIG. 3, in the second pixel _PEY , the white portion 13W is formed on the reflective display layer 13 facing the second color subpixel electrode 11m, the first color subpixel electrode 11c, and the third color subpixel electrode. An example in which a black portion 13B is formed at a portion of the reflective display layer 13 facing the pixel electrode 11y is illustrated.
Since FIG. 3 is a schematic diagram, the white portion 13W and the black portion 13B are drawn to be formed in the entire layer thickness, but the white portion 13W and the black portion 13B are only the surface 13a of the reflective display layer 13. Or you may form only in the vicinity of the surface 13a.

In the reflective display panel 1, light in various directions enters the protective layer 18. For example, when the incident light L0 parallel to the normal line N of the surface 13a of the reflective display layer 13 is incident, the incident light L0 is transmitted through the second colored layer 17m, so that the second color is transmitted through the second colored layer 17m. Only the component goes straight toward the reflective display layer 13. In the following, for simplicity, surface reflection and light scattering at the interface will be ignored.
Since the light transmission layer 19 has a light transmission property that transmits white light well, only the amount of light attenuates according to the transmittance, and the wavelength component hardly changes.
When the incident light L0 reaches the white portion 13W, the incident light L0 is reflected in the reverse direction along the normal line N, retransmits the light transmission layer 19 and the second colored layer 17m, and is emitted as the emitted light L0 ′ composed of the second color component. It is emitted to the outside.
On the other hand, the incident light L0 is also incident on the first colored layer 17c and the third colored layer 17y in the same manner, but the reflective display layer 13 facing the first colored layer 17c and the third colored layer 17y has a black portion 13B. Therefore, it is absorbed by the black portion 13B.
Accordingly, when viewed from the direction along the normal line N, the light emitted from the second pixel P _EY is only the emitted light L0 ′ of the second color. For example, if the second color is magenta, the display color of the part of the region of the second pixel _PEY is magenta.

On the other hand, consider a case where the region of the second pixel P _EY is viewed from a direction inclined by an angle θ with respect to the normal N in a cross section including the normal N and cut in the X direction.
In this case, as shown in FIG. 3, the observer observes the emitted lights L1 ′ and L2 ′, for example.

The outgoing light L1 ′ is light that is reflected by the white portion 13W from the incident light L1 that is inclined by θ toward the opposite side to the observation direction.
In this case, the incident light L1 passes through the protective layer 18, the second colored layer 17m, and the light transmission layer 19 in this order, similarly to the above-described incident light L0, except that the optical path is inclined. The light is reflected by 13W and passes through the light transmission layer 19, the second colored layer 17m, and the protective layer 18 in this order. For this reason, the emitted light L1 ′ becomes the light of the second color similarly to the emitted light L0 ′.

The emitted light L2 ′ is parallel to the incident light L1 incident on the second colored layer 17m, and the incident light L2 incident on the second colored layer 17m from the first colored layer 17c rather than the incident light L1 is the white portion 13W. It is the light reflected by.
In this case, the incident light L2 passes through the protective layer 18, the second colored layer 17m, and the light transmission layer 19 in this order, and is reflected by the white portion 13W, similarly to the above-described incident light L1. However, the reflected light passes through the light transmission layer 19, then passes through the first colored layer 17 c, and is emitted from the protective layer 18.
Therefore, the emitted light L2 ′ is light that has passed through the first colored layer 17c after passing through the second colored layer 17m. For example, when the first color is cyan and the second color is magenta, the emitted light L2 ′ is blue.
Similarly, although not shown in particular, the outgoing light incident from the third colored layer 17y, reflected by the white portion 13W and transmitted through the second colored layer 17m is red when the third color is yellow.
In this way, when the region of the second pixel _PEY is viewed from an oblique direction in the X direction, light such as blue and red generated in a part of the magenta is mixed, and thus, when viewed from the direction along the normal N As a result, a color difference occurs.
The above is an example of the case where the reflective display layer 13 is driven to white. However, even when the reflective display layer 13 is driven to gray of intermediate color, a color difference is generated as compared with the case of viewing from the direction along the normal N. It is.

Next, as shown in FIG. 4, consider a case where the region of the first pixel P _EX is viewed from a direction inclined by an angle θ with respect to the normal line N in a cross section including the normal line N and cut in the X direction. .
In the first pixel P _EX , for example, a white portion 13W is formed at a portion facing the second color sub-pixel electrode 11m.
The observer observes the emitted lights L11 ′ and L12 ′, for example. The illustrated outgoing lights L11 ′ and L12 ′ are separated by the same distance as in FIG. 3 in the X direction. However, since the second colored layer 17m extends along the X direction, all of the incident lights L11 and L12 and the emitted lights L11 ′ and L12 ′ are transmitted only through the second colored layer 17m. For this reason, both the emitted lights L11 ′ and L12 ′ are the second color (magenta), and no color difference occurs.
Other colors are mixed with the second color because the light that enters the left end of the second colored layer 17m and exits from the third colored layer 17y of the second pixel _PEY on the left side is adjacent to the right side. This light is incident from the first colored layer 17c of the second pixel _PEY and emitted from the right end of the second colored layer 17m in the drawing.
In the first pixel P _EX , since the second colored layer 17m extends in the X direction, most of the light entering and exiting the intermediate portion of the second colored layer 17m is the second color light having no color difference. Emitted.

In this way, when the region of the first pixel P _EX is viewed from the oblique direction in the X direction, a color difference occurs at both ends in the X direction, but since there is more light with no color difference, the second pixel from the same direction. The color difference is smaller than when viewing the P _EX area.
However, as the angle θ viewed by the observer increases, the area that causes a relative color difference increases.

As described above, the example of displaying the second color has been described as an example, but the viewing angle characteristics regarding the color difference in the case of full color display including the first color and the third color are also the same.
That is, even in various color displays, the viewing angle at which an allowable color difference is obtained in the cross section including the normal N and cut in the X direction is the first pixel P _EX compared to the region of the second pixel P _EY. The area of is larger. On the other hand, in the cross section including the normal N and cut in the Y direction, the viewing angle at which an allowable color difference is obtained is larger in the region of the second pixel P _EY than in the region of the first pixel P _EX. .

For this reason, when the color filter has a stripe shape extending in only one direction, there is a problem that a viewing angle when viewed in a direction orthogonal to the extending direction is reduced.
On the other hand, in the reflective display panel 1 of the present embodiment, the first filter portion 17X with the colored layer extending in the X direction and the second filter portion 17Y extending in the Y direction are in the X direction and the Y direction. They are alternately placed next to each other. That is, since the region where the viewing angle is large and the region where the viewing angle is small are alternately arranged in the two directions, the variation in the viewing angle due to the difference in the viewing direction is averaged.
As a result, the viewing angle bias related to the color difference of the reflective display panel 1 is reduced. Since the reflective display panel 1 reduces variations in color difference depending on the viewing direction, it is possible to display a full color image with good color difference when viewed from various directions.

[First Modification]
Next, a reflection type display device according to a modification (first modification) of the first embodiment will be described.
FIG. 5 is a schematic plan view showing the configuration of the main part of a reflective display device according to a modification (first modification) of the first embodiment of the present invention.

As shown in FIG. 5, the reflective display panel 1 </ b> A (reflective display device) of the present modification is replaced with the first electrode layer 11 of the reflective display panel 1 of the first embodiment, A first electrode layer 11A is provided.
FIG. 5 shows only a pair of the first pixel P _EX and the second pixel P _EY that are adjacent to each other in the X direction, but the number of the first pixels P _EX and the second pixels P _EY The arrangement pattern in plan view is the same as that in the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The first electrode layer 11A includes a first color sub-pixel electrode 11c and a second color sub-pixel electrode 11m in each first pixel P _EX (each second pixel P _EY ) in the first embodiment. In addition, nine sub-pixel electrodes 11a are provided instead of the third-color sub-pixel electrodes 11y.

In the first pixel P _EX (second pixel P _EY ), the nine sub-pixel electrodes 11a are arranged in a 3 × 3 rectangular lattice shape. Each sub-pixel electrode 11a is formed in a rectangular shape in plan view with four sides extending in the X direction or the Y direction. However, each sub-pixel electrode 11a may have a pseudo-rectangular shape in which a concave portion or a convex portion is formed in a part of the rectangle depending on the arrangement position of the switching element, for example.
In the first pixel P _EX (second pixel P _EY ), the three sets of three sub-pixel electrodes 11a arranged in the X (Y) direction are respectively arranged from the upper side to the lower side (left side to right side). ), The first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color for the first pixel P _EX (second pixel P _EY ) in the first embodiment. It is arranged in a rectangular area corresponding to the arrangement position of the sub-pixel electrode 11y.
Hereinafter, the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y in the first embodiment are arranged in a rectangular region corresponding to the arrangement position. The three sets of subpixel electrodes 11a are referred to as a first color subpixel electrode 11C, a second color subpixel electrode 11M, and a third color subpixel electrode 11Y, respectively.

In the first pixel P _EX (second pixel P _EY ), the first color sub-pixel electrode 11C and the second color sub-pixel electrode which are the three sub-pixel electrodes 11a arranged in the X (Y) direction. The same voltage is applied to 11M and the third color sub-pixel electrode 11Y at the time of driving and at the time of image display.
In the first pixel P _EX (second pixel P _EY ), the first color sub-pixel electrodes 11C and the second color sub-pixels arranged in three columns from the upper side to the lower side (left side to right side) in the figure. Voltages corresponding to the image signals of the color components of the first color, the second color, and the third color are applied to the electrode 11M and the third color sub-pixel electrode 11Y, respectively.
As long as a voltage can be applied in this way, each subpixel electrode 11a may be connected to a switching element whose applied voltage can be changed independently, or three subpixel electrodes to which the same voltage is applied. A configuration in which a common switching element is connected to 11a may be used.

  With such a configuration, each first colored layer 17c (second colored layer 17m, third colored layer 17y) of the color filter layer 17 in the present modification is a color of the first color (second color, third color). The three sub-pixel electrodes 11a driven by component image signals are opposed to each other with a light transmission layer 19 (not shown) interposed therebetween.

  The reflective display panel 1A of this modification is manufactured in the same manner as the reflective display panel 1 of the first embodiment except that the electrode pattern forming the first electrode layer 11A is different.

In the reflective display panel 1A of the present modification, the reflective display layer 13 for displaying the first color (second color, third color) is driven by applying a voltage to a set of three subpixel electrodes 11a. Except for this point, full color display can be performed in each first pixel P _EX and each second pixel P _EY in exactly the same manner as in the first embodiment.
In the present modification, the shape and arrangement of the color filter layer 17 are the same as those in the first embodiment. Therefore, as in the first embodiment, the viewing angle regarding the color difference of the reflective display panel 1 </ b> A is uneven. Reduced. In the reflective display panel 1A, variation in color difference depending on the viewing direction is reduced, so that a full-color image with good color difference can be displayed even when viewed from various directions.

[Second Modification]
Next, a color filter and a reflective display device according to a modification (second modification) of the first embodiment will be described.
FIG. 6 is a schematic plan view showing the configuration of the main part of a reflective display device according to a modification (second modification) of the first embodiment of the present invention.

As shown in FIG. 6, the reflective display panel 1 </ b> B (reflective display device) of the present modification includes a first electrode layer 11 and a color filter layer of the reflective display panel 1 of the first embodiment. In place of 17, the first electrode layer 11B and the color filter layer 27 (color filter) are provided.
FIG. 6 shows a configuration in the same range as in FIG. 2 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The first electrode layer 11B in the present modification is configured by changing the arrangement positions of the first pixels P _EX and the second pixels P _EY in the first embodiment.
As shown in FIG. 6, the first electrode layer 11B includes a first electrode portion 21X of a first pixel P _EX four pair arranged two-by-two in the X and Y directions, the X direction and A second electrode portion 21Y composed of a set of four second pixels _PEY arranged two by two in the Y direction is alternately arranged in the X direction and the Y direction.

The color filter layer 27 that is the color filter of the present embodiment is configured by alternately arranging the first filter portion 27X and the second filter portion 27Y in the X direction and the Y direction.
The first filter portion 27X (second filter portion 27Y) is disposed at a position facing the first electrode portion 21X (second electrode portion 21Y) with the light transmission layer 19 (not shown) interposed therebetween. .

The first filter portion 27X has a length in the longitudinal direction of each of the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y in the first embodiment that is approximately doubled. Two each of the first colored layer 27c, the second colored layer 27m, and the third colored layer 27y are provided.
Each first colored layer 27c (each second colored layer 27m, each third colored layer 27y) in the first filter portion 27X is composed of two rows of first color sub-pixels adjacent to each other in the X direction in the first electrode portion 21X. The electrode 11c (second color subpixel electrode 11m, third color subpixel electrode 11y) is disposed so as to face the light transmission layer 19 (not shown).

The second filter unit 27Y includes two first colored layers 27c, second colored layers 27m, and third colored layers 27y that are the same as the first filter unit 27X.
Each first colored layer 27c (each second colored layer 27m, each third colored layer 27y) in the second filter portion 27Y is composed of two rows of first color sub-pixels adjacent to each other in the Y direction in the second electrode portion 21Y. The electrode 11c (second color subpixel electrode 11m, third color subpixel electrode 11y) is disposed so as to face the light transmission layer 19 (not shown).

With such a configuration, each first colored layer 27c (each second colored layer 27m, each third colored layer 27y) of the first filter portion 27X is adjacent to each other in the X direction in the opposing first electrode portion 21X. It is extended in the X direction straddling the first pixel P _EX.
Each first colored layer 27c (each second colored layer 27m, each third colored layer 27y) of the second filter portion 27Y is adjacent to each second pixel P _EY adjacent in the Y direction in the opposing second electrode portion 21Y. Is extended in the Y direction.

  The reflective display panel 1B of this modification is the reflective display panel of the first embodiment, except that the electrode pattern forming the first electrode layer 11B is different from the filter pattern forming the color filter layer 27. 1 is produced.

The reflective display panel 1B of this modification can perform full color display in each first pixel P _EX and each second pixel P _EY in exactly the same manner as in the first embodiment.
In this modification, the first filter portion 27X formed of the colored layer group extending in the X direction is opposed to the four first pixels P _EX (pixel group) in the 2 × 2 array, and the 2 × 2 array is arranged. A second filter portion 27Y formed of a colored layer group extending in the Y direction is opposed to the four second pixels P _EY (pixel group).
For this reason, the direction in which the colored layer extends alternates between the X direction and the Y direction for every two pixels that perform full color display.
Therefore, similarly to the first embodiment, the viewing angle bias related to the color difference of the reflective display panel 1B is reduced. In the reflective display panel 1B, variation in color difference depending on the viewing direction is reduced, so that a full-color image with good color difference can be displayed even when viewed from various directions.

[Third Modification]
Next, a reflection type display device according to a modification (third modification) of the first embodiment will be described.
FIG. 7 is a schematic plan view showing the configuration of the main part of a reflective display device according to a modification (third modification) of the first embodiment of the present invention.

As shown in FIG. 7, the reflective display panel 1 </ b> C (reflective display device) of the present modification includes the first electrode layer 11 and the color filter layer of the reflective display panel 1 of the first embodiment. In place of 17, the first electrode layer 11A and the color filter layer 37 (color filter) are provided.
FIG. 7 shows a configuration in the same range as in FIG. 2 of the first embodiment.
This modification is a modification in which the first modification and the second modification are combined.
The following description will focus on differences from the first embodiment, the first modification, and the second modification.

The first electrode layer 11A in the present modification example has a 3 × 3 rectangular shape in each first pixel P _EX (each second pixel P _EY ), similarly to the first electrode layer 11A in the first modification example. Nine sub-pixel electrodes 11a arranged in a grid are provided.
However, in FIG. 7, for simplification of illustration, the sub-pixel electrodes 11a are drawn so as to be closely arranged.
In the first pixel P _EX (second pixel P _EY ), the three sets of three sub-pixel electrodes 11a arranged in the X (Y) direction are respectively arranged from the upper side to the lower side (left side to right side). ), As in the first modification, the first color sub-pixel electrode 11c and the second color sub-pixel of the first pixel P _EX (second pixel P _EY ) in the first embodiment. The electrode 11m and the third color sub-pixel electrode 11y are arranged in a rectangular region corresponding to the arrangement position.
Hereinafter, the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y in the first embodiment are arranged in a rectangular region corresponding to the arrangement position. The three sets of subpixel electrodes 11a are referred to as a first color subpixel electrode 11C, a second color subpixel electrode 11M, and a third color subpixel electrode 11Y, respectively, as in the first modification. .
In the first pixel P _EX (second pixel P _EY ), the configuration of each sub-pixel electrode 11a and the voltage applied to each sub-pixel electrode 11a when displaying an image are the same as in the first modification.

However, in the first embodiment and the first modification, the first pixel P _EX and the second pixel P _EY are alternately arranged in the X direction and the Y direction. On the other hand, in this modified example, two pixels of the same type are arranged adjacent to each other in the X phrase and the Y direction. That is, the arrangement is repeated such as “..., P _EX , P _EX , P _EY , P _EY,.
In this point, the present modification is the same as the arrangement of the first pixel P _EX and the second pixel P _EY in the second modification. However, in the second modified example, arranged in a 2 × 2 of the grid-shaped four first repeat unit of the pixel P _EX (first electrode portion 21X), arranged in 2 × 2 in a grid 4 The repeating units (second electrode unit 21Y) of the two second pixels P _EY were alternately arranged in the X direction and the Y direction. On the other hand, in the present modification, a repeating unit composed of three first pixels P _EX and one second pixel P _EY arranged in a 2 × 2 grid, and a 2 × 2 grid. Repeating units including one arranged first pixel P _EX and three second pixels P _EY are alternately arranged in the X direction and the Y direction.
For this reason, in the present modification, the first pixel P _EX and the second pixel P _EY are arranged adjacent to each other along a line extending diagonally at 45 degrees downward to the right in the figure, and obliquely inclined to the left in the figure. They are arranged alternately along a line extending at 45 degrees.
Although illustration is omitted, in this modification, an array in which the array pattern of FIG. 7 is reversed horizontally may be used. That is, the first pixel P _EX and the second pixel P _EY are alternately arranged along a line extending at 45 degrees diagonally downward to the right in the figure, and are of the same type along a line extending diagonally 45 degrees downward to the left in the figure. May be arranged next to each other.
Furthermore, it is an example that these diagonal arrangements appear on a line extending 45 degrees. In FIG. 7, since each pixel is drawn as a square, an oblique array is formed at 45 degrees diagonally. The diagonal arrangement direction may be along a line extending at an angle other than 45 degrees according to the diagonal direction of each pixel.

The color filter layer 37 that is the color filter of the present modification includes a plurality of first filter portions 37X and a plurality of second filter portions 37Y.
Each of the first filter portion 37X is in a position overlapping the two first pixel P _EX adjacent in the X direction, it is arranged across the not shown of the light transmission layer 19.
Each first filter portion 37X includes the same first colored layer 27c, second colored layer 27m, and third colored layer 27y as in the second modified example.
First colored layer 27c of the first filter portion 37X, the second colored layer 27m, and the third colored layer 27y has two first sub-pixel electrode for each first color in the pixel _{P EX} respectively adjacent in the X direction 11C, the second color sub-pixel electrodes 11M, and the third color sub-pixel electrodes 11Y.
Each second filter unit 37Y at a position overlapping the two second pixel P _EY adjacent in the Y direction, are arranged across the not shown of the light transmission layer 19.
Each second filter portion 37Y includes the same first colored layer 27c, second colored layer 27m, and third colored layer 27y as in the second modified example.
First colored layer 27c of the second filter portion 37Y, the second colored layer 27m, and the third colored layer 27y has two second sub-pixel electrode for each first color in the pixel _{P EY} respectively adjacent in the Y direction 11C, the second color sub-pixel electrodes 11M, and the third color sub-pixel electrodes 11Y.

  With such a configuration, each first colored layer 27c (second colored layer 27m, third colored layer 27y) of the color filter layer 37 in the present modification is a color of the first color (second color, third color). The three sub-pixel electrodes 11a driven by component image signals are opposed to each other with a light transmission layer 19 (not shown) interposed therebetween.

The color filter layer 37 that is a color filter of the present embodiment is configured by regularly and repeatedly arranging a first filter portion 37X and a second filter portion 37Y.
In particular, the first filter unit 37X (second filter unit 37Y) is independent in the X direction (Y direction) and is adjacent to the Y direction (X direction) in the Y direction (X direction). covering the respective first pixel of two adjacent in the X direction _{P EX} (second pixel _{P EY),} two of the two adjacent in the Y direction of the first pixel _{P EX} (second pixel _{P EY)} ing.
For this reason, also in the color filter layer 37, the direction in which the colored layer extends alternates between the X direction and the Y direction for every two pixels that perform full color display, as in the second modification.

  The reflective display panel 1C of the present modification is the reflective display panel of the first embodiment, except that the electrode pattern forming the first electrode layer 11A is different from the filter pattern forming the color filter layer 37. 1 is produced.

The reflective display panel 1C of this modification is a set of three sub-pixel electrodes 11a in each pixel for driving the reflective display layer 13 for displaying the first color (second color, third color). Except for performing the voltage application to the first color sub-pixel electrode 11C (second color sub-pixel electrode 11M, third color sub-pixel electrode 11Y), Full color display in the first pixel P _EX and each second pixel P _EY can be performed.
In this modification, the color filter layer 37 includes a first pixel of two adjacent in the X direction P _{EX (2} × 1 array pixel group), adjacent in the Y direction two first pixel P _{EX (1} The first filter portion 37X formed of a colored layer group extending in the X direction is opposed to the (× 2 array pixel group). Similarly, two second pixels P _EY (2 × 1 array pixel group) adjacent in the X direction, and two second pixels P _EX (1 × 2 array pixel group) adjacent in the Y direction, and Further, the second filter portion 37Y formed by the colored layer group extending in the Y direction faces each other.
For this reason, the direction in which the colored layer extends alternates between the X direction and the Y direction for every two pixels that perform full color display.
Therefore, similarly to the second modified example, the viewing angle bias related to the color difference of the reflective display panel 1C is reduced. In the reflective display panel 1C, variation in color difference depending on the viewing direction is reduced, so that a full-color image with good color difference can be displayed even when viewed from various directions.
In particular, in this modified example, the unit in which the direction in which the colored layer extends alternates is 2 × 1 (1 × 2), which is smaller than the second modified example of 2 × 2, thereby improving the color difference suppressing effect.

[Fourth Modification]
Next, a reflective display device according to a modification (fourth modification) of the first embodiment will be described.
FIG. 8 is a schematic plan view showing the configuration of the main part of a reflective display device according to a modification (fourth modification) of the first embodiment of the present invention.

As shown in FIG. 8, the reflective display panel 1 </ b> D (reflective display device) of the present modification includes a first electrode layer 11 and a color filter layer of the reflective display panel 1 of the first embodiment. In place of 17, the first electrode layer 11A and the color filter layer 47 (color filter) are provided.
FIG. 8 shows a configuration of a range in which pixels for full color display are arranged in a 3 × 3 grid.
Hereinafter, a description will be given centering on differences from the first embodiment.

11 A of 1st electrode layers in this modification are comprised by arranging the sub pixel electrode 11a similar to 11 A of 1st electrode layers in the said 1st modification in the shape of a rectangular lattice. However, in FIG. 8, for simplification of illustration, the sub-pixel electrodes 11a are drawn so as to be closely arranged.
Unlike the first modification example, the first electrode layer 11A in this modification example is arranged in a 4 × 4 rectangular lattice shape in each first pixel P _EX (each second pixel P _EY ). Sixteen sub-pixel electrodes 11a are provided.
The first pixel P _EX and the second pixel P _EY of this modification are different in the number of sub-pixel electrodes, but are alternately arranged in the X direction and the Y direction as in the first embodiment. .

In the first pixel P _EX (second pixel P _EY ) of this modification, four sets of the four sub-pixel electrodes 11 a arranged in the X (Y) direction are respectively arranged from the upper side to the lower side in the drawing. A first color sub-pixel electrode 41C, a second color sub-pixel electrode 41M, a third color sub-pixel electrode 41Y, and a fourth color sub-pixel electrode 41W are formed from the left side to the right side.
In the first pixel P _EX (second pixel P _EY ), the configuration of each sub-pixel electrode 11a is the same as that in the first modification.

The first color subpixel electrode 41C, the second color subpixel electrode 41M, and the third color subpixel electrode 41Y have a first color component, a second color component, and a third color component in accordance with an image signal. A driving voltage for displaying is applied.
A drive voltage for displaying the fourth color component is applied to the fourth color sub-pixel electrode 41W in accordance with the image signal. The fourth color may be a color other than the first color to the third color, or may be an achromatic color combined with the first color to the third color.
In this modification, an example in which the fourth color is an achromatic color will be described as an example.
In the first pixel P _EX (second pixel P _EY ), a first color sub-pixel electrode 41C (second color sub-pixel electrode) which is four sub-pixel electrodes 11a arranged in the X (Y) direction. 41M, the third color subpixel electrode 41Y, and the fourth color subpixel electrode 41W) have the same image signal corresponding to the first color (second color, third color, fourth color) component. A voltage is applied.

The color filter layer 47 that is the color filter of the present modification includes a plurality of first filter portions 47X and a plurality of second filter portions 47Y.
Each of the first filter portion 47X is in a position overlapping the first pixel P _EX, it is disposed across the not shown of the light transmission layer 19.
Each first filter portion 47X includes a first colored layer 47c and a second colored layer 47m that differ only in length from the first colored layer 27c, the second colored layer 27m, and the third colored layer 27y in the second modified example. , And a third colored layer 47y.
The first colored layer 47c, the second colored layer 47m, and the third colored layer 47y in the first filter unit 47X are the first color sub-pixel electrode 41C in the first pixel P _{EX and} the second color layer, respectively. The sub-pixel electrode 41M and the third color sub-pixel electrode 41Y are disposed at positions facing each other.
In the case of this modification, since the fourth color is an achromatic color, in each first filter portion 47X, the region facing the fourth color sub-pixel electrode 41W is a non-colored region 47w in which no colored layer is disposed. It is said that. However, when the fourth color is other than an achromatic color, a fourth colored layer (not shown) that transmits the fourth color wavelength component is disposed at a position facing the fourth color sub-pixel electrode 41W.
Similarly, each second filter portion 47Y includes a first colored layer 47c, a second colored layer 47m, a third colored layer 47y, and a non-colored region 47w extending in the Y direction.
First colored layer 47c of the second filter portion 47Y, the second colored layer 47m, the third colored layer 47y, and non-colored region 47w, respectively, the second first-color subpixel electrode 41C in the pixel _{P EY,} The second color sub-pixel electrode 41M, the third color sub-pixel electrode 41Y, and the fourth color sub-pixel electrode 41W are arranged to face each other.

  With such a configuration, each of the first colored layers 47c (second colored layer 47m, third colored layer 47y, non-colored portion region 47w) of the color filter layer 47 in the present modification example has the first color (second color, The four sub-pixel electrodes 11a driven by the image signals of the color components of the third color and the fourth color are opposed to each other with the light transmission layer 19 (not shown) interposed therebetween.

  The reflective display panel 1D of the present modification is the reflective display of the first embodiment except that the electrode pattern forming the first electrode layer 11A is different from the color filter pattern forming the color filter layer 47. Manufactured in the same manner as the panel 1.

The reflective display panel 1D according to the present modification is configured to drive the reflective display layer 13 for displaying the first color (second color, third color, and fourth color) by a set of four subpixels in each pixel. Except for applying the voltage to the first color subpixel electrode 41C (second color subpixel electrode 41M, third color subpixel electrode 41Y, fourth color subpixel electrode 41W), which is the electrode 11a, In the same manner as in the first embodiment, full-color display can be performed in each first pixel P _EX and each second pixel P _EY .
In the present modification, the first electrode layer 11A includes a fourth color sub-pixel electrode 41W in each pixel. For this reason, full-color display is performed in the same manner as in the first embodiment except that display is performed using the first to fourth colors. For this reason, as in the first embodiment, the viewing angle bias related to the color difference of the reflective display panel 1D is reduced. In the reflective display panel 1D, variation in color difference depending on the viewing direction is reduced, so that a full-color image with good color difference can be displayed even when viewed from various directions.
In particular, in the reflective display panel 1D of the present modification, when the non-colored region 47w is provided opposite to the fourth color sub-pixel electrode 41W, the fourth color sub-pixel electrode 41W can be driven more effectively. Bright full-color display can be performed.

[Second Embodiment]
Next, a color filter and a reflective display device according to a modification (second modification) of the second embodiment of the present invention will be described.
FIG. 9 is a schematic plan view showing the configuration of the main part of the reflective display device according to the second embodiment of the present invention.

As shown in FIG. 9, the reflective display panel 1E (reflective display device) of the present embodiment includes a first electrode layer 11 and a color filter layer of the reflective display panel 1 of the first embodiment. The first electrode layer 31 and the color filter layer 57 (color filter) are provided instead of the first electrode layer 31 and the color filter layer 57, respectively.
FIG. 9 shows a configuration in the range of the number of pixels similar to that in FIG. 2 of the first embodiment.
Hereinafter, a description will be given centering on differences from the first embodiment.

The reflective display panel 1E according to the present embodiment performs a full color display by combining the three colors with the reflective display panel 1 according to the first embodiment. This is different from the above.
The reflective display panel 1E has the same configuration as that of the first embodiment except that the number of drive electrodes and the type of colored layer are reduced from three to two in order to perform double color display.

The two colors used for the double color display are hereinafter referred to as a first color and a second color, but may be different from the first color and the second color in the first embodiment.
Examples of two colors used for double color display include red and cyan, magenta and green, yellow and blue, orange and green, and the like. However, the two colors are not limited to these combinations. As the two colors in the double color display, an appropriate combination of two colors according to the hue of the display color may be used.

The first electrode layer 31 is replaced with the first color sub-pixel electrode 11c, the second color sub-pixel electrode 11m, and the third color sub-pixel electrode 11y of the first electrode layer 11 in the first embodiment. The first color sub-pixel electrode 31c and the second color sub-pixel electrode 31m are provided.
The first color sub-pixel electrode 31c and the second color sub-pixel electrode 31m are provided with a driving voltage for driving the reflective display layer 13 in order to control the gradation of the first color and the second color used for double color display. Each drive electrode is applied to a predetermined region.
The external appearances of the first color subpixel electrode 31c and the second color subpixel electrode 31m in plan view extend long in one direction, like the first color subpixel electrode 11c in the first embodiment. It is a rectangular shape.

Similar to the first pixel P _EX and the second pixel P _EY in the first embodiment, the first electrode layer 31 includes a plurality of first pixels Q _EX arranged alternately in the X direction and the Y direction. And a second pixel _QEY .
The first pixel Q _EX (second pixel Q _EY ) includes a first color sub-pixel electrode 31c and a second color sub-pixel electrode 31m in a rectangular area on the substrate 10 (not shown). In the state where the longitudinal direction is aligned in the X (Y) direction, one is arranged in the Y (X) direction.

The color filter layer 57 includes a first filter portion 57X and a second filter portion 57Y that are alternately arranged in the X direction and the Y direction.
The first filter unit 57X includes a first colored layer 57c having a rectangular shape in plan view that transmits only the wavelength component of the first color, and a second colored layer 57m having a rectangular shape in plan view that transmits only the wavelength component of the second color. And extending in the X direction as the longitudinal direction.
First colored layer 57c and the second colored layer 57m of the first filter portion 57X, respectively, so as to overlap the first pixel _{Q EX} first color sub-pixel electrode 31c and the second color sub-pixel electrode 31m in Has been placed.
In the second filter portion 57Y, the first colored layer 57c and the second colored layer 57m similar to the first filter portion 57X extend with the Y direction as the longitudinal direction.
The first colored layer 57c and the second colored layer 57m in the second filter portion 57Y overlap with the first color subpixel electrode 31c and the second color subpixel electrode 31m in the second pixel _QEY , respectively. Has been placed.

In the reflective display panel 1E of the present embodiment, the first pixel Q _EX , the first color sub-pixel electrode 31c and the second color sub-pixel electrode 31m of each second pixel Q _EY according to the image signal. Double color display is performed by applying a voltage.
The reflective display panel 1E has the same configuration as that of the first embodiment except that the types of drive electrodes and the types of colored layers are reduced from three to two. It has the same action.
That is, the deviation of the viewing angle of the color difference of the reflective display panel 1E is reduced. In the reflective display panel 1E, variation in color difference depending on the viewing direction is reduced, so that a color image with good color difference can be displayed even when viewed from various directions.

In the description of each of the above embodiments, the arrangement position of the colored layer of the color filter corresponding to each pixel is different only in whether the longitudinal direction of the colored layer is the first direction or the second direction. Explained in the example. However, the arrangement of the colored layers of the color filter corresponding to each pixel may be changed in an arrangement pattern other than the orientation in the longitudinal direction for each pixel.
For example, the arrangement order of the colored layers in the short direction may be changed depending on the pixel position.

In the description of the first modified example, in the first pixel P _EX (second pixel P _EY ), the three sub-pixel electrodes 11 a arranged in the X (Y) direction are used for image display during driving. In both cases, the same voltage is applied. However, in a configuration in which each subpixel electrode 11a is connected to a switching element in which the applied voltage can be changed independently, different voltages may be applied to the three subpixel electrodes 11a. That is, gradation control including partially changing the reflectance of the reflective display layer 13 facing one colored layer may be performed.

  In the description of each of the above embodiments and each modification, an example in which the first direction and the second direction are orthogonal to each other has been described. However, the first direction and the second direction may intersect at an angle other than 90 °.

  In the description of each of the above-described embodiments and modifications, an example has been described in which the first filter unit and the second filter unit are each formed in a rectangular region. However, the first filter portion and the second filter portion may be formed in a region other than the rectangle as long as the shape can fill the plane.

  In the description of each of the embodiments and the modifications, the first filter unit and the second filter unit are described as examples in the case where they are alternately arranged in the first direction and the second direction. However, the first filter unit and the second filter unit need only appear alternately on average in the entire color filter, and do not have to be strictly arranged alternately. For example, the first filter unit and the second filter unit may be arranged so as to appear alternately on average by being arranged in an appropriate regular or irregular pattern.

  In the description of the third modification and the fourth modification, an example in which the first electrode layer 11A is used has been described. However, the first electrode layer 11A is the first electrode in the first modification. Similarly to the electrode layer 11B, a configuration in which rectangular sub-pixel electrodes are arranged in accordance with the arrangement of the colored layers may be used.

  In the description of each of the above embodiments and modifications, an example in which a color filter is used in a reflective display device has been described. However, the color filter of the present invention may be used alone or a reflective type, for example. You may use for display apparatuses other than a display apparatus.

Hereinafter, Examples 1 and 2 of the color filter and the reflective display device of each of the above embodiments will be described together with Comparative Examples 1 to 3.
Table 1 below shows the configurations and evaluation results of Examples 1 and 2 and Comparative Examples 1 to 3.

[Example 1]
Example 1 shown in [Table 1] is an example of the reflective display panel 1 provided with the color filter layer 17 of the first embodiment. That is, this is an example of a reflective display device including a color filter in which striped colored layers are alternately arranged in the X direction and the Y direction in order to perform full color display.
The color filter layer 17 and the reflective display panel 1 of Example 1 were manufactured as follows.

On the base material 15 made of PET, a second electrode layer 14 made of indium tin oxide (ITO) and a reflective display layer 13 made of an electrophoretic display medium are laminated in this order, whereby the first laminated body. Formed.
Thereafter, the first electrode layer 11 made of ITO was formed on the substrate 10 made of glass. On the 1st electrode layer 11, the reflective display layer 13 was bonded together through the contact bonding layer 12 which consists of a transparent acrylic adhesive.
On the base material 15 in this state, a polyester resin-based resin for inkjet receptive layer NS-141LX (trade name; manufactured by Takamatsu Yushi Co., Ltd.) was continuously applied using a comma coater.
Thereafter, the resin for the ink jet receiving layer was dried with a vacuum dryer for 5 minutes. As a result, an ink fixing layer 16 having an average film thickness of 10 μm was formed.

In each first pixel P _EX and each second pixel P _EY of the first electrode layer 11, the width in the X direction was 600 μm, and the width in the Y direction was 600 μm.
The materials and layer thicknesses of the second electrode layer 14, the substrate 15, and the ink fixing layer 16 were selected so that the optical distance as the light transmission layer 19 was 100 μm.

The ink for forming the color filter layer 17 was manufactured as follows.
In this embodiment, cyan (hereinafter C) is used for the first color, magenta (M) is used for the second color, and yellow (Y) is used for the third color.
First, as shown in [Table 2] below, cyan (Y) dispersion, magenta (M) dispersion, and yellow (Y) dispersion containing C, M, and Y colorants were prepared.

As shown in [Table 2], the C dispersion was mixed with 70 parts by weight of diethylene glycol monoethyl ether acetate (hereinafter abbreviated as DGMEA), 10 parts by weight of dispersant and 20 parts by weight. Of C color pigment.
As the dispersant, DISPER BYK (registered trademark) -111 (trade name; manufactured by Big Chemi) was used. Examples of the pigment include C.I. I. Pigment Blue 15: 3 was used.
In order to sufficiently disperse the pigment in the mixed solution, a bead mill dispersion disperser was used. In this way, a C dispersion was prepared.
In the M dispersion, the dispersant and the pigment in the C dispersion are Solsperse (registered trademark) 20000 (trade name; manufactured by Lubrizol Corporation), C.I. I. It was produced in the same manner as the C dispersion, except that it was changed to Pigment Red 122.
In the Y dispersion, the pigment of the M dispersion is C.I. I. It was produced in the same manner as the M dispersion, except that it was changed to Pigment Yellow 150.

  Cyan (C) ink, magenta (M) ink, and yellow (Y) ink are added to the obtained C dispersion, M dispersion, and Y dispersion, respectively, by adding a binder resin and a solvent and stirring well. It was made. The composition of each ink is shown in [Table 3] below.

As shown in [Table 3], C ink was prepared by 20 parts by weight of C dispersion, 20 parts by weight of binder resin made of melamine resin, and 60 parts by weight of DGMEA as an organic solvent.
As the melamine resin, MW-22 (trade name; manufactured by Sanwa Chemical Co., Ltd.) was used.
M ink and Y ink were prepared in the same manner as C ink except that the C dispersion in C ink was changed to M dispersion and Y dispersion, respectively.

Thereafter, the produced C ink, M ink, and Y ink are drawn on the ink fixing layer 16 by an ink jet printing apparatus, whereby the first colored layer 17c, the second colored layer 17m, and the third colored layer 17y, respectively. Pattern was applied.
As the ink jet printing apparatus, an ink jet printing apparatus equipped with a 12 pl, 180 dpi (180 dots per 2.54 cm) ink jet head manufactured by Seiko Instruments Inc. was used.
Each colored layer had a width in the longitudinal direction of 590 μm and a width in the short direction of 190 μm. The arrangement pitch of the first filter portion 17X and the second filter portion 17Y adjacent to each other was matched to the arrangement pitch of the first pixel P _EX and the second pixel P _EY adjacent to each other. For this reason, the colored portion area ratio was 93.4%.
The coated ink was dried for 5 minutes in a vacuum dryer. Thereby, the color filter layer 17 was formed.

Thereafter, a protective layer 18 made of polyimide was laminated on the color filter layer 17.
In this way, Example 1 of the first embodiment was manufactured.

[Example 2]
Example 2 shown in [Table 1] is an example of the reflective display panel 1E provided with the color filter layer 57 of the second embodiment. That is, this is an example of a reflective display device including a color filter in which stripe-shaped colored layers are alternately arranged in the X direction and the Y direction in order to perform double color display.
In the reflective display panel 1E of the second embodiment, the size of each first pixel Q _EX and each second pixel Q _EY of the first electrode layer 31 is the same as each first pixel P _{EX in} the first embodiment. The size of each second pixel P _EY was adjusted.
Each colored layer had a width in the longitudinal direction of 390 μm and a width in the short direction of 190 μm. For this reason, the colored portion area ratio was 92.6%.

[Comparative Examples 1-3]
In Comparative Example 1 shown in [Table 1], a striped color filter in which colored layers of three colors having the same arrangement as the first filter portion 17X of Example 1 are extended only in the X direction is provided in the Y direction. The reflective display device of the full color display is the same as that of the first embodiment except that they are arranged at an equal pitch.
In Comparative Example 2 shown in [Table 1], a striped color filter in which three colored layers having the same arrangement as the second filter portion 17Y of Example 1 are extended only in the Y direction is used in the X direction. The reflective display device of the full color display is the same as that of the first embodiment except that they are arranged at an equal pitch.
In Comparative Example 3 shown in [Table 1], a striped color filter in which two colored layers having the same arrangement as the first filter portion 57X of Example 2 are extended only in the X direction is provided in the Y direction. This is a reflective display device for double color display similar to that of the second embodiment except that it is arranged at an equal pitch.

[Evaluation]
The reflective display devices of Examples 1 and 2 and Comparative Examples 1 to 3 were evaluated based on the viewing angle characteristics of the color difference measured as follows.
With the produced reflective display device, the display color viewed from the front (normal direction) and the X and Y directions are inclined by ± 45 ° with respect to the normal while displaying the magenta color. The color difference (ΔE * ab) from the display color viewed from the direction was measured with a spectrophotometer.
Here, the inclination direction of “−45 °” refers to an inclination from the magenta (second color) side to the cyan (first color) side in the arrangement of the colored layers arranged in the X (Y) direction in each pixel. Direction. For example, an inclination direction of −45 ° in the X (Y) direction (described as “X- (Y−)” in the measurement direction column of [Table 1]) is X (Y) in FIGS. It means that the measurement was performed from the 45 ° direction from the left (upper) side to the right (lower) side in the figure along the direction arrow. The inclination direction of “+ 45 °” (described as “X + (Y +)” in the measurement direction column of [Table 1]) is the reverse direction of “−45 °”.
The determination of the color difference (ΔE * ab) is good when ΔE * ab ≦ 3 (good, “◯” in the determination column of [Table 1]), and bad (no good, [table] when ΔE * ab> 3. 1] was determined as “×”).
“Good” color difference determination means that the threshold of ΔE * ab is 3, and the viewing angle in the measurement direction is 45 ° or more. The color difference determination “defective” means that the viewing angle in the measurement direction is less than 45 °, with a threshold value of ΔE * ab set to 3.
The overall determination is good when it is determined that all color differences in X−, X +, Y−, and Y + are good (good, “◯” in the determination column of [Table 1]), X−, X +, and Y−. , Y + was determined to be defective when it was determined to be defective (no good, “×” in the determination column of [Table 1]).

[Evaluation results]
[Table 1] shows measured values, determination results, and overall determination results of the color difference ΔE * ab in each measurement direction in each example and each comparative example.
In Examples 1 and 2, all the color differences were 3 or less in each measurement direction, the color differences were determined to be “good”, and the overall determination was also “good”. Further, the difference between the color difference in the X direction and the color difference in the Y direction (difference between X− and Y−, difference between X + and Y +) is 0.2 to 0.4 in Example 1, and 0 in Example 2. .2 to 0.9, both of which were smaller than 3.
On the other hand, in Comparative Examples 1 and 2, when the measurement direction is the longitudinal direction of the colored layer, the color difference is less than 3 and determined to be “good”. It was even smaller than the color difference in the same direction.
However, when the measurement direction is the arrangement direction of the colored layers (short direction), the color difference was 7.2 to 8.8, which greatly exceeded 3, and thus was determined as “defective”.
Therefore, the overall determination was “bad”. In particular, the difference between the color difference in the X direction and the color difference in the Y direction also greatly exceeded 3, and the deviation of the color difference was extremely large.
In Comparative Example 3, when the measurement direction was the X direction, which is the longitudinal direction of the colored layer, it was determined as “good”. This color difference was the same as the color difference in the same direction of Example 2 of the double color display.
However, when the measurement direction was the colored layer arrangement direction (short direction), the color difference was 8.7 and 8.5, greatly exceeding 3, and thus determined as “defective”.
Therefore, the overall determination was “bad”.

When the stripe-shaped colored layer is extended only in one direction as in Comparative Examples 1 to 3, it can be seen that the color difference is deteriorated and the viewing angle is narrowed when viewed from a direction orthogonal thereto.
On the other hand, in Examples 1 and 2, since the longitudinal direction of the colored layer alternates, the directionality of the colored layer is relaxed, and the color difference is not greatly deteriorated depending on the measurement direction. For this reason, it can be seen that the deviation of the viewing angle is suppressed and the viewing angle characteristics are improved.

As mentioned above, although preferable each embodiment and each modification of this invention were described with each Example, this invention is not limited to these embodiment, a modification, and an Example. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention.
Further, the present invention is not limited by the above description, and is limited only by the appended claims.

1, 1A, 1B, 1C, 1D, 1E Reflective display panel (reflective display device)
11, 11A, 11B, 31 First electrode layer 11a Subpixel electrodes 11c, 11C, 31c, 41C First color subpixel electrodes 11m, 11M, 31m, 41M Second color subpixel electrodes 11y, 11Y, 41Y Subpixel electrode for three colors 41W Subpixel electrode for fourth color 13 Reflective display layer (multiple reflective display units)
13B Black portion 13W White portion 14 Second electrode layer 16 Ink fixing layer 17, 27, 37, 47, 57 Color filter layer (color filter)
19 Light transmissive layers 17c, 27c, 37c, 47c, 57c First colored layers 17m, 27m, 37m, 47m, 57m Second colored layers 17y, 27y, 47y Third colored layers 17X, 27X, 37X, 47X, 57X First Filter parts 17Y, 27Y, 37Y, 47Y, 57Y Second filter part 21X First electrode part 21Y Second electrode part 47w Non-colored part regions L0, L1, L2, L11, L12 Incident light L0 ′, L1 ′, L2 ', L11', L12 'emitted light N normal _{P EX, Q EX} first pixel _{P EY, Q EY} second pixel

Claims (9)

A plurality of colored layers having different transmission wavelength bands and extending in one direction are arranged in a second direction intersecting the first direction in a state in which the respective longitudinal directions are aligned with the first direction on the arrangement surface. A first filter section being configured;
The first filter unit is arranged adjacent to the first filter unit, and the plurality of colored layers are arranged in the first direction in a state in which the respective longitudinal directions are aligned with the second direction on the arrangement surface. Two filter sections;
A color filter. The plurality of colored layers in the first filter portion and the second filter portion are colored in mutually different colors,
The color filter according to claim 1. A plurality of the first filter units and the second filter units are provided, and are arranged adjacent to each other alternately in the first direction and the second direction.
The color filter according to claim 1. The first direction and the second direction are directions orthogonal to each other.
The color filter of any one of Claims 1-3. The color filter according to any one of claims 1 to 4,
A plurality of reflective display units arranged to face the plurality of colored layers in the first filter unit and the second filter unit of the color filter, respectively, and the reflectance can be changed independently;
A reflective display device comprising: The first filter unit and the second filter unit are arranged in units of pixels which are color display units in the plurality of reflective display units.
The reflective display device according to claim 5. At least one of the first filter unit and the second filter unit is arranged in units of a pixel group in which a plurality of pixels which are color display units in the plurality of reflective display units are adjacent to each other.
The reflective display device according to claim 5. In the first filter portion and the second filter portion, a non-colored region is formed facing at least one of the reflective display portions in the pixel,
The reflective display device according to claim 6 or 7. A light transmission layer disposed between the color filter and the plurality of reflective display units;
The reflective display apparatus of any one of Claims 5-8.

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