JP2008203666A - Color filter for transflective liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter for a transflective liquid crystal display device which has good color reproducibility, and in which the luminance of a pixel part in an area for reflected light is high. <P>SOLUTION: The color filter for transflective liquid crystal display device has a transparent substrate, a pixel part for transmitted light and a pixel part for reflected light formed on the transparent substrate. The pixel part for the transmitted light has a red pixel part composed of lamination of a yellow colored layer and a magenta colored layer, a green pixel part constituted of lamination of the yellow colored layer and a cyan colored layer and a blue pixel part constituted of lamination of the cyan colored layer and the magenta colored layer. The pixel part for the reflected light has: a cyan pixel part constituted of the cyan colored layer; a magenta pixel part constituted of the magenta colored layer; and a yellow pixel part constituted of the yellow colored layer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a color filter for a transflective liquid crystal display device which is used in a transflective liquid crystal display device and has excellent color reproducibility.

  In recent years, a transflective liquid crystal display device utilizing external light reflection and backlight transmitted light has been developed as a liquid crystal display device. The transflective liquid crystal display device uses external light to display. The conventional reflective color liquid crystal display device is advantageous in that it also has a backlight and can perform display (transmission display) using the backlight even when the surroundings are dark.

  In this transflective liquid crystal display device, usually, a color filter having a colored layer of three primary colors of red (R), green (G), and blue (B) in each of a transmitted light region and a reflected light region When the electrodes corresponding to the R, G, and B pixels of this color filter are turned on and off, the liquid crystal operates as a shutter, and the R, G, and B pixels are turned on. Passes and color display is performed.

  Therefore, for example, as shown in FIG. 5, in the transflective liquid crystal display device including the color filter 100 and the counter substrate 110 disposed to face the color filter 100, the reflected light used for the reflective display in the transparent substrate 101. A color filter that approximates the display quality between the transmissive display and the reflective display by forming colored layers having different color densities in the transparent region r and the transmitted light region t used for transmissive display, respectively. Generally known. However, in such a color filter, a process for individually forming the reflected light region and the transmitted light region is required for each of the R, G, and B pixels, and thus the number of steps is complicated. There was a problem.

  On the other hand, in order to obtain the same effect while reducing the number of steps, for example, as shown in FIG. 6, a predetermined film thickness is provided only in the reflected light region r used for reflective display in the transparent substrate 101. The transparent resin layer 102 is formed, and the colored layer 103 is formed so as to cover the transparent resin layer 102, so that the thickness of the colored layer formed in the reflected light region r is the transmitted light used for transmissive display. A color filter formed so as to be thinner than the thickness of the colored layer formed in the use region t has been proposed (see Patent Document 1). However, in such a color filter, the relationship between the film thickness of the transmitted light region t and the reflected light region r is influenced by the physical characteristics of the material used to form the colored layer 103 and various process conditions. Therefore, there is a problem that it may be difficult to control the film thickness to a preferable one.

  On the other hand, the color filter used in the transflective liquid crystal display device is required to improve the luminance of the reflected light region. Therefore, for example, in Patent Document 2, in order to improve the luminance of the reflected light region, the reflected light region includes a red pixel portion in which a magenta colored layer and a yellow colored layer are arranged in parallel, a yellow colored layer, and a cyan colored layer. A green pixel portion arranged in parallel and a blue pixel portion in which a cyan coloring layer and a magenta coloring layer are arranged in parallel. A color filter for a transflective liquid crystal display device that performs display is disclosed. However, when two color layers are simultaneously colored to display one color, the color coordinates in the xy chromaticity diagram of the displayed color are straight lines connecting the color coordinates of the colors to be simultaneously colored. Since it is located on the upper side, there is a problem that the area where the color can be expressed, that is, the figure area connecting the color coordinates of red, green and blue is narrowed and the color reproducibility is lowered.

JP 2004-085986 A Japanese Patent Laid-Open No. 2002-258029

  Therefore, it is desired to provide a color filter for a transflective liquid crystal display device that has good color reproducibility, high luminance in the pixel portion of the reflected light region, and excellent manufacturing efficiency.

  The present invention is a color filter for a transflective liquid crystal display device having a transparent substrate, and a pixel portion for transmitted light and a pixel portion for reflected light formed on the transparent substrate, wherein the pixel portion for transmitted light is A red pixel portion comprising a laminate of a yellow colored layer and a magenta colored layer, a green pixel portion comprising a laminate of a yellow colored layer and a cyan colored layer, and a blue pixel portion comprising a laminate of a cyan colored layer and a magenta colored layer. And the reflected light pixel portion includes a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. A color filter for a liquid crystal display device is provided.

According to the present invention, the pixel portion for reflected light includes a cyan pixel portion, a magenta pixel portion, and a yellow pixel portion, so that two colored layers are colored simultaneously to display one color pixel portion. Compared with the reflected light pixel portion, the color reproduction region can be widened, so that the reflected light pixel portion with good color reproducibility can be obtained. In addition, since the transmittance of each pixel portion in the reflected light pixel portion can be high, the luminance of the reflected light pixel portion is high when used in a transflective liquid crystal display device. it can.
Further, according to the present invention, the transmitted light pixel portion includes the red pixel portion, the green pixel portion, and the blue pixel portion formed by laminating the colored layers of the above colors, so that the color of the transmitted light pixel portion is reduced. A color filter having a wide reproduction area and good color reproducibility can be obtained.
Furthermore, according to the present invention, since 6 pixels are formed from the colored layers of three colors, a color filter that can be manufactured with high manufacturing efficiency can be obtained.

  In the above invention, the transmitted light pixel portion preferably further includes a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. This is because the color reproducibility becomes better in the transmitted light pixel portion.

  According to the present invention, it is possible to obtain a color filter for a transflective liquid crystal display device having good color reproducibility, high luminance in the reflected light region, and excellent manufacturing efficiency.

Hereinafter, the color filter for a transflective liquid crystal display device of the present invention (hereinafter sometimes simply referred to as a color filter) will be described.
The color filter for a transflective liquid crystal display device according to the present invention is a color filter for a transflective liquid crystal display device having a transparent substrate, a transmitted light pixel portion and a reflected light pixel portion formed on the transparent substrate. The transmitted light pixel portion includes a red pixel portion formed by stacking a yellow colored layer and a magenta colored layer, a green pixel portion formed by stacking a yellow colored layer and a cyan colored layer, and a cyan colored layer and a magenta colored portion. A blue pixel portion made of a laminate of layers, and the reflected light pixel portion includes a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. It is characterized by having.

  The color filter for a transflective liquid crystal display device according to the present invention includes, for example, as shown in FIG. 1, a transparent substrate 1, a transmitted light pixel portion a and a reflected light pixel portion b formed on the transparent substrate 1. The transmitted light pixel portion a includes a red pixel portion 4R formed by stacking a yellow colored layer 3Y and a magenta colored layer 3M, and a green pixel portion 4G formed by stacking a yellow colored layer 3Y and a cyan colored layer 3C. , And a blue pixel portion 4B composed of a laminate of a cyan colored layer 3C and a magenta colored layer 3M, and the reflected light pixel portion b includes a cyan pixel portion 4C composed of a cyan colored layer 3C, and a magenta colored layer 3M. The magenta pixel portion 4M and the yellow pixel portion 4Y including the yellow coloring layer 3Y are provided. In addition, the light-shielding part 2 is normally formed between the pixel parts of each color.

  An example of a plan view of such a color filter for a transflective liquid crystal display device is shown in FIG. For example, as shown in FIG. 2, the color filter for the transflective liquid crystal display device includes a transmitted light pixel portion a having a red pixel portion 4R, a green pixel portion 4G, and a blue pixel portion 4B, a cyan pixel portion 4C, A reflected light pixel portion b having a magenta pixel portion 4M and a yellow pixel portion 4Y.

  In recent years, in such a color filter for a transflective liquid crystal display device, improvement in luminance of a reflected light region has been demanded. For example, as described above, a reflected light pixel portion includes a magenta colored layer and a yellow colored layer. Proposal of a color filter consisting of a red pixel part in which layers are arranged in parallel, a green pixel part in which yellow and cyan colored layers are arranged in parallel, and a blue pixel part in which cyan and magenta colored layers are arranged in parallel Has been made. However, such a color filter has a problem that color reproducibility is low.

  On the other hand, in the present invention, the reflected light pixel portion is composed of three color pixel portions, a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. As a result, the region formed by connecting the color coordinates of each pixel part in the xy chromaticity diagram is compared with the color filter that displays the color of the two colors by developing the two colored layers described above. Can be wide. Therefore, a color filter having a wide color reproduction region and good color reproducibility can be obtained.

  Further, according to the present invention, the reflected light pixel portion includes a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. Since the colored layer, the magenta colored layer, and the yellow colored layer are usually colored layers having high transmittance over a wide wavelength range, the brightness is higher than that of the three primary colors red, green, and blue. A high pixel portion can be obtained. Therefore, a color filter for a transflective liquid crystal display device in which the luminance of the pixel portion in the reflected light region is high can be obtained.

  Further, in the present invention, the transmitted light pixel portion includes a red pixel portion formed by stacking a yellow colored layer and a magenta colored layer, a green pixel portion formed by stacking a yellow colored layer and a cyan colored layer, and cyan coloring. Displaying red, green, and blue colors by arranging the colored layers that make up each color pixel part in parallel by forming the blue pixel part by laminating layers and magenta colored layers. Compared to the above, the color reproduction region can be widened. The reason is shown below. For example, in the xy chromaticity diagram shown in FIG. 3, a yellow color layer R and a magenta color layer are arranged in parallel, and a red color coordinate R ′ that is simultaneously developed is obtained by combining a yellow color coordinate Y and a magenta color coordinate M. The color coordinate R of the color indicated by the red pixel portion formed by laminating the yellow colored layer and the magenta colored layer is the yellow color coordinate Y and the magenta color coordinate M. It will be located outside the connected straight line. Similarly, the green color coordinate G ′ displayed by arranging the yellow colored layer and the cyan colored layer in parallel is on a straight line connecting Y and C (cyan color coordinate) and the cyan colored layer. The blue color coordinate B ′ displayed by arranging magenta colored layers in parallel is located on a straight line connecting C and M, but the yellow colored layer and cyan colored layer in the present invention are laminated. The color coordinates G of the green pixel portion and the color coordinates B of the blue pixel portion formed by laminating the cyan colored layer and the magenta colored layer are located outside the straight line connecting the color coordinates of the laminated colored layers. Therefore, it is possible to make the area of the figure connecting the color coordinates of R, G, and B wider than the area of the figure connecting the color coordinates of R ′, G ′, and B ′. It becomes. Therefore, according to the present invention, a color filter with good color reproducibility can be obtained even in the transmitted light pixel portion.

Furthermore, according to the present invention, for example, a cyan colored layer is formed by forming a pixel portion of six colors using three colored layers of a cyan colored layer, a magenta colored layer, and a yellow colored layer. It can be manufactured by performing three steps of a step, a step of forming a magenta colored layer, and a step of forming a yellow colored layer. Therefore, a color filter for a transflective liquid crystal display device manufactured with high manufacturing efficiency can be obtained.
Hereinafter, the color filter for a transflective liquid crystal display device of the present invention will be described in detail for each configuration.

1. Reflected Light Pixel Unit First, the reflected light pixel unit used in the present invention will be described. The transmitted light pixel portion used in the present invention has a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer.

  The average transmittance within the wavelength range of 460 nm to 520 nm of the cyan colored layer used in the present invention is preferably 70% or more, particularly preferably in the range of 85% to 95%. The average transmittance of the magenta colored layer within the wavelength range of 620 nm to 700 nm is preferably 80% or more, particularly preferably 90% or more, and the average transmittance within the wavelength range of 400 nm to 460 nm is 70%. As mentioned above, it is especially preferable to be in the range of 80% to 90%. Furthermore, the average transmittance of the yellow colored layer in the wavelength range of 520 nm to 700 nm is preferably 85% or more, particularly 95% or more. This is because by setting the above-described average transmittance of each colored layer in the above range, it is possible to achieve higher luminance when used in a transflective liquid crystal display device.

  As a method for measuring the transmittance, a method of measuring the transmittance of the complementary colored layer using the transmittance of the transparent substrate described later as a reference (100%) can be employed. As the device, an ultraviolet / visible spectrophotometer (for example, Hitachi U-4000) or a device having a photodiode array as a detector (for example, Otsuka Electronics MCPD) can be used.

  The thickness of each reflected light pixel portion made of such colored layers is appropriately selected so that each reflected light pixel portion has a desired color. When the film thickness of the pixel portion is 1, the thickness of the reflected light pixel portion is preferably in the range of 0.2 to 1, and more preferably in the range of 0.3 to 0.8, particularly 0. It is preferable to be within the range of 4 to 0.6. This is because the luminance of the reflected light pixel portion can be further improved and the color reproducibility can be improved.

  Specifically, the film thickness of the reflected light pixel portion is preferably in the range of 0.5 μm to 4.0 μm, more preferably in the range of 0.6 μm to 3.0 μm, particularly 0. It is preferable to be within a range of 8 μm to 2.0 μm.

  In addition, the film thickness of the said pixel part for reflected light can be confirmed by observing using a scanning electron microscope (SEM) etc.

2. Next, the transmitted light pixel portion used in the present invention will be described. The transmitted light pixel portion used in the present invention includes a red pixel portion in which a yellow colored layer and a magenta colored layer are laminated, a green pixel portion in which a yellow colored layer and a cyan colored layer are laminated, and a cyan colored layer and a magenta colored layer. Are stacked in a blue pixel portion.

  The red pixel portion, the green pixel portion, and the blue pixel portion used in the present invention are each formed by stacking two colored layers, but the film thickness ratio of the two colored layers to be stacked is formed. The pixel portion to be adjusted is appropriately adjusted to have a desired color.

  Moreover, it is preferable that the film thickness as a laminated body of a red pixel part, a green pixel part, and a blue pixel part used for this invention shall be in the range of 0.8 micrometer-8 micrometers, for example, and 1.0 micrometer-5. It is preferable to be in the range of 0 μm, particularly in the range of 1.2 μm to 3.0 μm.

  In the present invention, the transmitted light pixel portion includes, in addition to the red pixel portion, the green pixel portion, and the blue pixel portion, a cyan pixel portion made of a cyan colored layer, a magenta pixel made of a magenta colored layer, and a yellow colored layer. It is preferable to have a six-color pixel portion of the yellow pixel portion. This is because the color reproducibility becomes better in the transmitted light pixel portion.

  As a color filter for a transflective liquid crystal display device in which such a pixel portion for transmitted light having six color pixel portions is formed, for example, as shown in FIG. 4, a red pixel portion 4R, a green pixel portion 4G, a blue color Transmitted light pixel part a having pixel part 4B, cyan pixel part 4C, magenta pixel part 4M and yellow pixel part 4Y, and reflected light pixel part having cyan pixel part 4C, magenta pixel part 4M and yellow pixel part 4Y and those having b.

  The thickness of the cyan pixel portion, magenta pixel portion, and yellow pixel portion in the transmitted light pixel portion is preferably larger than the thickness of the cyan pixel portion, magenta pixel portion, and yellow pixel portion in the reflected light pixel portion. . This is because the transmitted light pixel portion and the reflected light pixel portion can have the same color. As a method of making the thickness of the cyan pixel portion, magenta pixel portion, and yellow pixel portion in the transmitted light pixel portion larger than the thickness of the cyan pixel portion, magenta pixel portion, and yellow pixel portion in the reflected light pixel portion. Can be the same as, for example, a method of forming a colored layer of the same color described later with different film thicknesses. Specifically, for example, when forming by a photolithography method, a method using a photomask having a halftone part with adjusted transmittance, a method of forming two colored layers of the same color, or an inkjet method, for example. In the case of forming, a method for adjusting the discharge amount of the ink jet apparatus to be used can be used.

  The film thickness of the cyan pixel portion, magenta pixel portion, and yellow pixel portion in the transmitted light pixel portion is preferably in the range of, for example, 0.8 μm to 8 μm, and more preferably in the range of 1.0 μm to 5.0 μm. In particular, it is preferable to be in the range of 1.2 μm to 3.0 μm.

  The film thickness of the transmitted light pixel portion can be confirmed by observing with a scanning electron microscope (SEM) or the like.

  The yellow colored layer, magenta colored layer, and cyan colored layer used in the transmitted light pixel portion can be the same as the colored layer used in the reflected light pixel portion described above. Omitted.

3. Transparent substrate Next, the transparent substrate used in the present invention will be described. The transparent substrate used in the present invention is not particularly limited as long as it can form the transparent resin layer and the colored layer and is transparent to visible light, and is used for a general color filter. It can be the same as the transparent substrate.

  Specifically, a transparent rigid material having no flexibility such as quartz glass, Pyrex (registered trademark) glass, synthetic quartz plate, or a transparent flexible flexible material such as a transparent resin film or an optical resin plate. Materials and the like.

4). Next, a color filter for a transflective liquid crystal display device according to the present invention will be described. The color filter for a transflective liquid crystal display device of the present invention may have other members as necessary in addition to the above-described reflected light pixel portion, transmitted light pixel portion, and transparent substrate. As such other members, for example, a light shielding part, a protective layer, a transparent electrode layer, an alignment film, and the like may be appropriately provided as necessary.

  The light shielding part, the protective layer, the transparent electrode layer, and the alignment film can be the same as those used for a color filter for a general transflective liquid crystal display device. Omitted.

  In addition, when the color filter for a transflective liquid crystal display device of the present invention is used in a transflective liquid crystal display device, the transmitted light used for displaying the reflected light and the transmitted light pixel portion is used for displaying the reflected light pixel portion. Since it is necessary to adjust the distance that each of the light passes through the liquid crystal, the transflective liquid crystal display device is usually provided with an optical path difference adjustment layer that adjusts the optical path difference between reflected light and transmitted light. Such an optical path difference adjusting layer may be provided on the color filter side, or may be provided on the counter substrate side arranged to face the color filter. When the optical path difference adjusting layer is provided on the color filter side, the optical path difference adjusting layer may be provided between the colored layer and the transparent substrate, or may be provided on the colored layer.

5. Next, a method for manufacturing a color filter for a transflective liquid crystal display device according to the present invention will be described. The method for producing a color filter for a transflective liquid crystal display device of the present invention is not particularly limited as long as it is a method capable of forming the transmitted light pixel portion and the reflected light pixel portion. For example, the yellow pixel portion Forming a yellow colored layer in the forming region, the red pixel portion forming region, and the green pixel portion forming region; and forming a magenta colored layer in the magenta pixel portion forming region, the red pixel portion forming region, and the blue pixel portion forming region. A magenta colored layer forming step to be formed, and a cyan colored layer forming step of forming a cyan colored layer in the cyan pixel portion forming region, the green pixel portion forming region, and the blue pixel portion forming region may be included.

  The method for forming a colored layer in the yellow colored layer forming step, the magenta colored layer forming step and the cyan colored layer forming step is not particularly limited as long as it can form a colored layer on a transparent substrate. Instead, for example, a method of forming by a photolithography method or an inkjet method using a coloring layer forming coating solution of each color can be mentioned. In the present invention, a method of forming a colored layer by photolithography is preferable. Note that a method for forming a colored layer by a photolithography method and an inkjet method can be the same as a method generally used for forming a colored layer in a color filter.

  The yellow colored layer forming step, the magenta colored layer forming step, and the cyan colored layer forming step are steps for forming a colored layer of the same color in each of the three regions. Coloring formed in at least one of the three regions In the case where the film thickness of the layer is different from the film thickness of the colored layer formed in another region, for example, in the photolithography method, a method of forming using a photomask having a halftone portion with adjusted transmittance or the same color For example, in an ink jet method, a method of adjusting the discharge amount of an ink jet device to be used can be used.

  Further, as described above, when the transmitted light pixel portion is composed of six color pixel portions, the film thicknesses of the yellow pixel portion, magenta pixel portion, and cyan pixel portion in the transmitted light pixel portion are set to the reflected light pixels. The above-described method can also be used when forming thicker than the yellow pixel portion, magenta pixel portion, and cyan pixel portion.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The following examples illustrate the present invention more specifically.

[Example 1]
(Formation of light shielding part)
A photosensitive resin composition (CFRR DN-83, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on a non-alkali glass substrate having a thickness of 0.7 mm by spin coating, and dried at 100 ° C. for 3 minutes. A light shielding part of 1.5 μm was formed. Thereafter, the light-shielding portion thus formed is exposed to a light-shielding pattern with an ultra-high pressure mercury lamp, developed with 0.05 wt% potassium hydroxide aqueous solution, and then left at 180 ° C. for 30 minutes. Heat treatment was performed to form a light shielding portion (black matrix) in the light shielding region other than the region where the colored layer was to be formed.

(Colored layer formation process)
<Yellow colored layer forming step>
On the glass substrate on which the light-shielding portion is formed as described above, a coating solution for forming a yellow colored layer having the following composition is applied by a spin coating method to a coating thickness of 1.0 μm in the formation region of the reflected light pixel portion. And then dried in an oven at 70 ° C. for 3 minutes to form a coating film of a yellow colored layer forming coating solution.
Thereafter, the yellow colored layer forming coating liquid coating film formed in this way is used to form a yellow pixel portion forming region for reflected light, a red pixel portion forming region for transmitted light, and a green color using an ultrahigh pressure mercury lamp. After exposing only the pixel portion formation region, development is performed with a 0.05 wt% potassium hydroxide aqueous solution, and then a heat treatment is performed by leaving it in an atmosphere of 180 ° C. for 30 minutes to form a yellow colored layer on each pixel portion. Formed.
a. Composition of coating liquid for forming yellow colored layer (1) C.I. I. Pigment Yellow 150 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Ciba・ Irgacure 907 manufactured by Specialty Chemicals
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate * Polymer I is benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (molar ratio) ) Is added 16.9 mol% of 2-methacryloyloxyethyl isocyanate to 100 mol% of the copolymer.

<Cyan colored layer forming step>
In addition, by the same method as the yellow colored layer forming step described above, a coating film is formed using a cyan colored layer forming coating solution having the following composition, and a cyan pixel portion forming region for reflected light and a transmitted light for transmitting light are formed. Only the green pixel portion formation region and the blue pixel portion formation region were exposed to form a cyan colored layer on each pixel portion.
b. Composition of Cyan Colored Layer Forming Coating Liquid (1) C.I. I. Pigment Green 36 + C. I. Pigment Blue 15: 3 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Irgacure 907 manufactured by Ciba Specialty Chemicals)
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate

<Magenta colored layer formation process>
Further, by the same method as the yellow colored layer forming step described above, a coating film is formed using a magenta colored layer forming coating liquid having the following composition, a magenta pixel portion forming region for reflected light, and a transmitted light for transmitting light. Only the blue pixel portion formation region and the red pixel portion formation region were exposed to form a magenta colored layer on each pixel portion.
c. Composition of magenta colored layer forming coating solution (1) C.I. I. Pigment Violet 23 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Ciba・ Irgacure 907 manufactured by Specialty Chemicals
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate

[Comparative Example 1]
(Formation of light shielding part)
The light shielding part was formed in the same procedure as in Example 1.

(Formation of transparent resin layer)
In the same manner as in the yellow colored layer forming step of Example 1, a coating film is formed using a transparent resin layer forming coating liquid having the following composition, and only the pixel region for reflected light is exposed, and the reflected light region A transparent resin layer was formed as a base for the film.
d. Composition of coating solution for forming transparent resin layer (1) Monomer (SR399, SR399) 7 parts by weight (2) Polymer I 10 parts by weight (3) Initiator (Ciba Specialty Chemicals Irgacure 907)
3 parts by weight (4) Propylene glycol monomethyl ether acetate 80 parts by weight

(Colored layer formation process)
<Red colored layer forming step>
On the glass substrate on which the light shielding part is formed as described above, a red layer forming coating liquid having the following composition is applied by a spin coating method so as to have a coating thickness of 1.0 μm at the pixel part for reflected light. Then, it was dried in an oven at 70 ° C. for 3 minutes to form a coating film of a red layer forming coating solution. At this time, the coating thickness in the pixel portion for transmitted light was 2.0 μm.
Thereafter, the coating film of the red layer forming coating liquid thus formed is exposed only to the red pixel portion forming region for reflected light and the red pixel portion forming region for transmitted light using an ultrahigh pressure mercury lamp. After that, development was performed with a 0.05 wt% aqueous potassium hydroxide solution, and then heat treatment was performed by leaving it in an atmosphere of 180 ° C. for 30 minutes to form a red colored layer on each pixel portion.
e. Composition of red colored layer forming coating solution (1) C.I. I. Pigment Red 177 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Ciba・ Irgacure 907 manufactured by Specialty Chemicals
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate

<Green colored layer formation process>
Further, by the same method as the red colored layer forming step described above, the film thickness of the reflected light pixel portion and the transmitted light pixel portion is equal to that of the red pixel using the green colored layer forming coating liquid having the following composition. A coating film was formed so as to be exposed, and only the green pixel portion forming region for reflected light and the green pixel portion forming region for transmitted light were exposed to form a green colored layer on each pixel portion.
f. Composition of green colored layer forming coating solution (1) C.I. I. Pigment Green 36 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Ciba・ Irgacure 907 manufactured by Specialty Chemicals
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate

<Blue colored layer forming step>
Further, by the same method as the red colored layer forming step described above, the film thickness of the reflected light pixel portion and the transmitted light pixel portion is the same as that of the red pixel using the blue layer forming coating liquid having the following composition. A coating film was formed to expose the blue pixel portion forming region for reflected light and the blue pixel portion forming region for transmitted light, and a blue colored layer was formed on each pixel portion.
g. Composition of blue colored layer forming coating solution (1) C.I. I. Pigment Blue 15: 6 6 parts by weight (2) Dispersant (Disperbic 161 manufactured by Big Chemie) 3 parts by weight (3) Monomer (SR399 manufactured by Sartomer) 4 parts by weight (4) Polymer I 5 parts by weight (5) Initiator (Irgacure 907 manufactured by Ciba Specialty Chemicals)
2 parts by weight (6) 80 parts by weight of propylene glycol monomethyl ether acetate

[Evaluation]
Liquid crystal display devices were produced using the color filters of Example 1 and Comparative Example 1, and the chromaticity of each pixel portion in the transmitted light pixel portion was measured with a spectrophotometer using a white LED light source. The results are shown in Table 1 in xy chromaticity display. Table 1 also shows chromaticity regions that can be displayed with respect to the color reproduction region in the NTSC standard at this time.

  Further, assuming reflection display in the above-described liquid crystal display device, each pixel portion in the transmitted light pixel portion having a film thickness twice as large as the manufactured reflected light pixel portion is assumed to be under sunlight and using a D65 light source. The chromaticity was measured. The results are shown in Table 2 in xy chromaticity display. Table 2 also shows the white display luminance in the reflective display at this time.

  As is apparent from Tables 1 and 2, in Example 1, a color filter having good color reproducibility and high brightness of the reflected light pixel portion could be produced.

It is a schematic sectional drawing which shows an example of the color filter for transflective liquid crystal display devices of this invention. It is a top view which shows an example of the color filter for transflective liquid crystal display devices of this invention. It is an xy chromaticity diagram for explaining a color filter for a transflective liquid crystal display device of the present invention. It is a top view which shows the other example of the color filter for transflective liquid crystal display devices of this invention. It is a schematic sectional drawing which shows the conventional transflective liquid crystal display device. It is a schematic sectional drawing which shows the conventional transflective liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Light-shielding part 3C ... Cyan colored layer 3M ... Magenta colored layer 3Y ... Yellow colored layer 4R ... Red pixel part 4G ... Green pixel part 4B ... Blue pixel part 4C ... Cyan pixel part 4M ... Magenta pixel part 4Y ... Yellow pixel part a ... Transmitted light pixel part b ... Reflected light pixel part

Claims (2)

A color filter for a transflective liquid crystal display device having a transparent substrate, a pixel portion for transmitted light and a pixel portion for reflected light formed on the transparent substrate,
The transmitted light pixel portion includes a red pixel portion formed by stacking a yellow colored layer and a magenta colored layer, a green pixel portion formed by stacking a yellow colored layer and a cyan colored layer, and a cyan colored layer and a magenta colored layer. It has a blue pixel portion made of a laminate, and the reflected light pixel portion has a cyan pixel portion made of a cyan colored layer, a magenta pixel made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. A color filter for a transflective liquid crystal display device.   2. The half according to claim 1, wherein the transmitted light pixel portion further includes a cyan pixel portion made of a cyan colored layer, a magenta pixel portion made of a magenta colored layer, and a yellow pixel portion made of a yellow colored layer. Color filter for transmissive liquid crystal display devices.

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