JP5560865B2 - Color filter substrate for transflective liquid crystal display device, manufacturing method thereof, and transflective liquid crystal display device - Google Patents

Description

  The present invention relates to a color filter substrate for a transflective liquid crystal display device, a method for manufacturing the same, and a transflective liquid crystal display device, and more particularly to a transflective liquid crystal display using a backlight on the back surface of the liquid crystal display device and external light in combination. The present invention relates to a device color filter substrate, a method for manufacturing the same, and a transflective liquid crystal display device including the color filter substrate. In particular, the present invention relates to a color filter substrate suitable for a liquid crystal display device of a vertical electric field method or an oblique electric field method such as VA or TN.

  In recent years, there has been a demand for further higher image quality, lower cost, and lower power consumption in thin display devices such as liquid crystal displays. In color filters for liquid crystal display devices, electrical characteristics such as sufficient color purity, high contrast, flatness, and low dielectric constant, which are unlikely to hinder liquid crystal driving, are required.

  In high-quality liquid crystal displays, there are liquid crystal alignment methods such as VA (Vertically Alignment), HAN (Hybrid-aligned Nematic), TN (Twisted Nematic), OCB (Optically Compensated Bend), and CPA (Continuous Pinwheel Alignment). A display with a wide viewing angle and a fast response has been put to practical use.

  In liquid crystal display devices such as the VA method, which has a wide viewing angle and liquid crystal part molecules aligned in parallel on the substrate surface such as glass, and which is easily compatible with high-speed response, and the HAN method, which is effective for a wide viewing angle, Are required to have higher levels of electrical characteristics such as flatness (thickness uniformity and reduction in unevenness of the color filter surface) and dielectric constant. In such a high-quality liquid crystal display, a technique for reducing the thickness of the liquid crystal cell (the thickness of the liquid crystal layer) has become a major issue in order to reduce coloring when viewed in an oblique direction.

  In the VA method, for example, as disclosed in Patent Document 1 and Patent Document 2, MVA (Multi-Domain Vertically Alignment), PVA (Patterned Vertically Alignment), VAECB (Vertical Alignment Electrically Controlled Birefringence), and VAHAN (Vertical Alignment Hybrid). Development of various improved display modes such as -aligned Nematic) and VATN (Vertically Alignment Twisted Nematic) is in progress.

  In a vertical electric field type liquid crystal display device in which a driving voltage is applied in the thickness direction of the liquid crystal such as the VA method, a faster liquid crystal response, a wide viewing angle technique, and a higher transmittance are main problems. The technique disclosed in Patent Document 2 is a technique that uses a horizontal electric field and a vertical electric field in combination and uses an oblique electric field generated between opposing substrates via liquid crystal for controlling the liquid crystal.

  In order to reduce coloration when the liquid crystal display device is viewed in an oblique direction, there is a technique in which a colored layer is overlapped and used as a spacer in order to make the liquid crystal cell thickness uniform in addition to flattening the color filter. Forming the spacers by laminating a colored layer or the like by a photolithography technique is excellent from the viewpoint of securing a uniform liquid crystal cell gap.

  A general liquid crystal cell such as a VA method or a TN method is configured by bonding a color filter side of a color filter substrate and an array side of an array substrate so as to face each other. Usually, a spacer is provided in the color filter to secure the liquid crystal thickness of the liquid crystal cell, and the thickness of the liquid crystal layer sandwiched between the two substrates is controlled. In many cases, a transmissive liquid crystal display device is provided with a diffusion plate for diffusing light together with the above-described backlight on the back surface of the liquid crystal cell on the array substrate side.

  In general, a basic configuration of a liquid crystal display device such as a VA method or a TN method includes a color filter substrate having a common electrode and a plurality of pixel electrodes (for example, TFT elements that are electrically connected to a comb tooth) that drive the liquid crystal. The liquid crystal is sandwiched between the array substrate provided with a transparent electrode formed in a shape pattern. In this configuration, the liquid crystal is driven by applying a driving voltage between the common electrode on the color filter and the pixel electrode formed on the array substrate side. The transparent conductive film as a common electrode on the pixel electrode or color filter surface is usually a thin film of conductive metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or IGZO (Indium Garium Zinc Oxide). .

  In a transflective LCD, one pixel is used by reflecting light from a backlight from the back surface of the liquid crystal display as transmitted light and reflecting light from outside light or front light. The liquid crystal display device is used by being divided into a reflecting portion. Or it is a liquid crystal display device which can turn off a backlight and can visually recognize the display with bright outside light such as sunlight in a bright outdoor room.

  In order to solve light leakage and coloring problems associated with the main wavelengths of red, green, and blue light, a technique for varying the thickness of the liquid crystal (a cell gap that differs for each color) is known (see, for example, Patent Document 3). ). In addition, a technique for forming a different retardation layer for each of red, green, and blue colors, a technique for disposing a quarter-wave retardation layer for the purpose of adjusting the retardation in the reflective portion of the liquid crystal display device, etc. It is publicly known (for example, see Patent Documents 4, 5, 6, and 7). The techniques disclosed in Patent Documents 4, 5, and 6 propose color filters having different phase differences between the reflection part and the transmission part.

  However, none of these patent publications disclose a technique for optimizing the phase difference of the retardation layer on the colored pixel for each color including the thickness direction retardation of the colored pixel of the color filter. In addition, these patent documents do not describe a technique related to the light scattering layer.

  Further, it has been proposed to provide a light-shielding partition wall and form a color filter, an alignment film, a retardation film, and a liquid crystal layer thickness adjusting layer by a droplet discharge method (see, for example, Patent Document 8).

JP 2007-2640437 A JP 2010-15183 A JP-A-3-30126 Japanese Patent No. 4269702 JP 2006-85130 A JP 2006-292847 A JP 2008-165250 A JP 2009-128860 A

  The technique disclosed in Patent Document 3 solves the wavelength dispersion problem of the liquid crystal in red, green, and blue display in the transmissive liquid crystal display device, but the technique in the reflection part in the transflective liquid crystal display device. Has not been studied. Further, no consideration is given to the thickness direction retardation of the colored pixel derived from the organic pigment (coloring material) used for the color filter colored pixel.

  A red pixel of a color filter used in a liquid crystal display device usually has a diketopyrrolopyrrole red pigment (CI Pigment Red 254) and an anthraquinone red pigment (CI Pigment Red 177), which are red organic pigments on a transparent resin such as acrylic. ) And a small amount of yellow pigment dispersed therein. Red pixels using these pigments as colorants have a considerably large thickness direction retardation of +20 nm to +60 nm. Similarly, for a green pixel, it is common to use a halogenated copper phthalocyanine-based green pigment (CI Pigment Green 36) as a main pigment, add a yellow pigment for color adjustment, and disperse it in a transparent resin. is there. However, a green pixel using the copper halide phthalocyanine-based green pigment as a colorant has a thickness direction retardation that is greatly negative from -20 nm to -50 nm. As a color material for a blue pixel, a metal phthalocyanine-based blue pigment and a dioxazine-based purple pigment are generally used, and these pigments also have variations in phase difference depending on pigment synthesis and the composition of the colored composition. Even if such a phase difference derived from an organic pigment is ignored and a phase difference mounted on a liquid crystal display device is designed, it is difficult to avoid light leakage and unintentional coloring. Note that the present inventors have disclosed a technique for adjusting the thickness direction retardation of colored pixels in Japanese Patent No. 43066736 for the purpose of improving oblique visibility during black display of a liquid crystal display device. It has been found that it can be used in the present invention.

  The technique disclosed in Patent Document 3 is a technique related to a transmissive liquid crystal display device, and there is no disclosure regarding a technique related to a reflective portion of a transflective liquid crystal display device, suggesting a phase difference technique formed in the reflective portion. Nor.

  In Patent Document 4, a retardation layer including an alignment film and a polymer liquid crystal is formed on the color filter located on the liquid crystal layer side of the liquid crystal display device according to claim 2, and the polymer liquid crystal is randomly aligned in the transmission part. (A phase difference is not given) and a technique having an effective phase difference with respect to substantially circularly polarized light or linearly polarized light is disclosed in the reflecting portion. In other words, this technology is effective in that the alignment film on the color filter used in the liquid crystal display device is rubbed only on the reflection portion using a photoresist pattern, and the retardation layer on the rubbed alignment film is aligned. This is a technique for providing a correct phase difference. On the color filter, an alignment film and a retardation layer are formed on the entire surface.

  In this technology, the retardation layer of the transmission part is randomly oriented. However, unlike the liquid crystal of a liquid crystal display device, it cannot be controlled by applying an electric field, so there is a problem of residual phase difference, and the residual phase difference is transmitted. Display will be degraded. In addition, since this technique laminates a color filter and a retardation layer on the reflective film, it is difficult to use the reflective film as a light reflective electrode, and a separate transparent conductive film must be formed. There is also. Further, no consideration is given to the thickness direction retardation of the colored pixel derived from the organic pigment (coloring material) used for the color filter colored pixel.

  In the technique disclosed in Patent Document 5 and some examples of Patent Document 7, the retardation layer is formed so as to cover the transmission part and the reflection part (or on the entire surface of the color filter). There is a problem of residual phase difference in the transmission part of the phase difference layer.

  In the technique disclosed in Patent Document 6 and in some examples of Patent Document 7, a technique for forming a retardation layer only in the reflective portion of the colored pixel of the color filter is disclosed. However, when a retardation layer such as a quarter-wave layer is formed in the reflective portion in the form of an independent pattern with a rectangular cross-section, it tends to flow during the hardening process due to heat treatment, and shape deformation that adversely affects display is likely to occur. . In addition, when a retardation layer such as a quarter wavelength layer is formed by using photocuring or thermosetting together with photocuring, an unreacted monomer of the polymerizable liquid crystal compound used for forming the quarter wavelength layer There is a problem that it tends to remain on the surface portion of the quarter wavelength layer. The unreacted monomer may contaminate the liquid crystal used in the liquid crystal display device and cause deterioration in display characteristics, or may cause a change with time in the phase difference of the quarter wavelength layer itself. Many of the polymerizable liquid crystal compounds are oxygen-inhibited, and the unreacted portions as described above are likely to remain even after the film hardening after exposure, leading to deterioration of the optical function.

  As described above, when the 1/4 wavelength layer is not formed for each colored pixel and is used as a solid film, the phase difference remains in a portion (transmission portion) where the 1/4 wavelength phase difference is unnecessary, An adverse effect on display quality was inevitable.

  In order to form a quarter wavelength layer or a half wavelength layer on the color filter, when using a material capable of imparting a retardation function such as a polymerizable liquid crystal compound, an alignment film is formed on the color filter in advance, and the alignment is performed. It is necessary to impart alignment ability to the film by rubbing or photo-alignment. In the case where an alignment film having no alignment ability or an alignment film is not formed, a sufficient phase difference cannot be obtained. In addition, it is important to form the retardation layer only on the reflection portion. However, the selective formation of the alignment film formed prior to the reflection portion is most easily performed by an inkjet method (in addition, depending on the printing method). In the formation of the alignment film, the fine pattern of the liquid crystal pixel size is insufficient in terms of accuracy.)

  However, when the colored pixels of the color filter are flat or only have stepped steps, the alignment film material flows out onto the peripheral pixels and the BM when ink droplets of the alignment film material are landed by inkjet. . In this case, in order to hold the ink droplet, it is necessary to form a recess in the colored pixel. Only the steps of the colored pixels disclosed in Patent Document 4 and Patent Document 5 cannot prevent the ink droplet from flowing out. In the technique disclosed in Patent Document 6, there is no description of forming an alignment film before forming the retardation layer, the means for setting the alignment axis of the retardation layer is unknown, and sufficient for the retardation layer. There is a high possibility that a large phase difference cannot be given.

  In the techniques of Patent Documents 5, 6, and 7 that disclose the provision of a retardation layer in a transflective liquid crystal display device, no consideration is given to the thickness direction retardation of a colored pixel derived from an organic pigment used for a color filter colored pixel. Not.

  In the transflective liquid crystal display device, the techniques of Patent Documents 4, 5, 6, and 7 disclosing the installation of the retardation layer assume that the intensity of sunlight is high and the liquid crystal display device is used under parallel light. However, the liquid crystal display device could not be used in both bright and dark environments. Reflective display under parallel light such as sunlight has a problem that moire tends to occur due to the relationship with the pixel arrangement.

  Patent Document 8 discloses a technique in which a light-shielding partition wall is provided on a substrate in advance and a color filter or a retardation layer is formed between the partition walls by a droplet discharge method. There are several problems with this technology. First, it is necessary to form a light-shielding partition wall at the boundary between the transmissive portion and the reflective portion, lowering the aperture ratio of the pixel, resulting in dark display. Secondly, the partition wall having a height for holding droplets ejected from the nozzle is an important component of this technology. However, it is a light-shielding and photosensitive material (for example, Patent Document 8). In paragraphs 0048 and 0060, there is a description of the method, etc. However, there is no description of the height and film thickness of the partition wall), and it is difficult to produce a high yield with a fine line suitable for a liquid crystal display device and a good cross-sectional shape. is there. Even with the printing method, it is difficult to form a partition portion having a line width of 10 μm and a height of 4 μm in a good shape with a rectangular cross section, as in the case of the photosensitive light-shielding material. It is difficult to apply to LCDs and mobile devices.

  The partition wall having a height cuts off oblique incident light and reflected light at the time of reflective display, and increases dark display. In addition, there is no description about the specific material of the light-shielding partition wall of the present technology, and in the configuration of the reflective common electrode disclosed in the present technology, the reflection of light is mirror-like, and the wide field of view in the reflective display Cannot be secured. Patent Document 8 does not disclose a technique related to paper white display using a light scattering film.

  In the constituent member used in the technique disclosed in Patent Document 8, it is difficult to form a spacer that uniformly maintains the liquid crystal layer thickness of the display area including the reflective display area, which is caused by substrate deflection, temperature, and pressure changes. Display unevenness resulting from a change in the thickness of the liquid crystal layer is not taken into consideration.

  In addition, these conventional technologies improve the flatness between the green pixel and the light-shielding layer (light-shielding frame) in consideration of the visibility of the human eye, and do not increase the number of manufacturing processes. A technique for a display device is not disclosed.

  The present invention has been made in view of the above circumstances, and a color filter substrate for a transflective liquid crystal display device suitable for a vertical electric field method such as a VA method or a TN method, or an oblique electric field method liquid crystal display device, and its manufacture It is an object to provide a method and a transflective liquid crystal display device.

  In order to solve the above-described problem, a first aspect of the present invention includes a light shielding layer disposed on the outer periphery of an effective display area on a transparent substrate, and a colored pixel including a red pixel, a green pixel, and a blue pixel, a spacer, In the color filter substrate for a transflective liquid crystal display device in which a retardation layer of 1 and a transparent conductive film are formed in an effective display area, a concave portion is formed in each of the colored pixels, and the first retardation layer Is provided in the concave portion and has a function of rotating the polarization of incident light converted into linearly polarized light by 90 degrees by one round-trip transmission in the thickness direction of the first retardation layer, and The sum of the retardation in the thickness direction of the colored pixels in each recess and the retardation in the thickness direction of the first retardation layer in the recess is the sum of the phase differences in the red pixels ≧ the sum of the phase differences in the green pixels ≧ blue pixels Phase difference in Providing transflective color filter substrate for a liquid crystal display device wherein there of the relationship.

  In such a color filter substrate for a transflective liquid crystal display device, the phase difference in the thickness direction of the colored pixels of the plurality of colors is expressed as follows: red pixel thickness direction phase difference ≧ green pixel thickness direction phase difference ≧ blue pixel thickness direction A phase difference relationship can be obtained.

  The green pixel may contain zinc halide phthalocyanine as a main color material.

  The ratio of the thickness of the colored pixels in the recesses to the thickness of the colored pixels other than the recesses can be in the range of 1/2 to 1/4.

  A first cell gap adjusting layer can be formed on the first retardation layer.

  The difference in height between the surface of the first cell gap regulating layer and the surface of the colored pixel other than the concave portion can be made approximately ½ of the thickness of the liquid crystal layer of the liquid crystal display device.

  The first cell gap adjusting layer can be a light scattering layer.

  A black matrix made of the same material as that of the light shielding layer may be further provided so as to partition the colored pixels in an effective display area on the transparent substrate.

  The thickness of the black matrix can be made thinner than the thickness of the light shielding layer.

  The transparent conductive film may be disposed between the black matrix and the transparent substrate.

  The transparent conductive film may be disposed between the black matrix and the colored pixels.

  A second cell gap adjustment layer stacked on the light shielding layer may further be provided, and a total film thickness of the light shielding layer and the second cell gap adjustment layer may be substantially the same as the film thickness of the green pixel. it can.

  A second retardation layer laminated on the light shielding layer is further provided, and the total thickness of the light shielding layer and the second retardation layer can be substantially the same as the thickness of the green pixel. .

  The spacer may be an alignment control structure that also serves as a liquid crystal alignment control disposed in the center of the colored pixel.

  An alignment control protrusion made of the same material as the spacer can be disposed on the colored pixel.

  The transparent conductive film can be laminated on at least a plurality of colored pixels and the first cell gap adjustment layer.

  The film thicknesses of the colored pixels of the plurality of colors can be in a relationship of red pixel film thickness ≦ green pixel film thickness ≦ blue pixel film thickness.

  According to a second aspect of the present invention, there is provided a transflective liquid crystal display device comprising the above-described color filter substrate for a transflective liquid crystal display device.

  According to a third aspect of the present invention, there is provided a method of manufacturing the above-described color filter substrate for a transflective liquid crystal display device, wherein concave portions are formed in the plurality of colored pixels by a photolithography technique using a gray tone photomask. Provided is a method for producing a color filter substrate for a transflective liquid crystal display device, comprising a step of forming and a step of forming an alignment film for aligning a retardation layer in the recess by an inkjet method. .

  According to the present invention, a color filter substrate optimal for a vertical electric field type liquid crystal display device such as a VA type or an oblique electric field type is provided, and in particular, a transflective liquid crystal display device excellent in both transmissive display and reflective display. Is provided.

  In the color filter substrate according to the present invention, forming the concave portion in the colored pixel includes forming a thin colored layer necessary for the reflective portion, selective formation of the alignment film before forming the retardation layer due to the concave shape, and the retardation layer. There is an advantage that a plurality of effects such as improvement of the shape can be obtained at a time.

  Further, according to the present invention, the phase difference between the blue pixel, the green pixel, and the red pixel, or the sum of the phase differences obtained by adding the phase difference of the retardation layer to these colored pixels, the sum of the phase differences of the red pixels ≧ green pixels By satisfying the relationship of the sum of the phase differences of ≧ the sum of the phase differences of the blue pixels, it is possible to completely compensate for the chromatic dispersion that is not sufficient with only the retardation layer. At least the phase difference layer formed in the color filter and the reflective part is composed of a red pixel phase difference <a green pixel phase difference<a blue pixel phase difference or a red pixel phase difference> a green pixel phase difference <a blue pixel phase difference. It is possible to eliminate an undesirable relationship such as a phase difference, and to reduce light leakage in black display and coloring in display.

  In particular, the phase difference of the reflection part of the blue pixel and further the blue pixel is made smaller than the phase difference of the other colored pixels while maintaining the wavelength relationship (wavelength relationship) of the transmission peaks of the other colored pixels. Blue light leakage in the display can be reduced. In addition, setting the thickness of the colored pixel in the relationship of red pixel ≦ green pixel ≦ blue pixel means that the thickness of the liquid crystal layer on each color pixel is red display portion ≧ green display portion ≧ blue display portion. Therefore, it is possible to improve the image quality of the liquid crystal display device in the entire visible range.

  Further, according to the present invention, a transflective liquid crystal display device is provided by disposing a retardation layer, a cell gap adjusting layer together with the retardation layer, or a light scattering layer having a function of diffusing light to the colored pixels. An optimal color filter substrate can be provided. As will be described later, the light scattering layer is obtained by dispersing fine particles having different refractive indexes in a transparent resin matrix, and the fine particles are randomized when the light scattering layer is applied on the color filter. By this randomization, moire does not occur even in reflective display using highly parallel incident light such as sunlight.

  Furthermore, according to the present invention, when the cell gap adjusting layer or the light scattering layer is laminated after forming the retardation layer, the cell gap adjusting layer or the light scattering layer is effective for protecting the retardation layer, and the reason is as follows. As will be described later, a retardation layer having stable retardation characteristics can be obtained by promoting the curing of the retardation layer. As described above, according to the present invention, the alignment film for the alignment treatment of the retardation layer can be selectively formed in the concave portion of the colored layer in a few steps in advance, so that the transflective liquid crystal display As a device, it is possible to provide a color filter substrate capable of obtaining high image quality at the reflection portion as well as the transmission portion.

  In addition, according to the present invention, the step of the frame portion can be eliminated by laminating the cell gap adjusting layer or the retardation layer on the frame-shaped light shielding layer, and the thickness of the lamination is substantially the same as that of the green pixel. By doing so, it is possible to provide a liquid crystal display device that eliminates light leakage due to disorder of liquid crystal alignment.

  Green is an important color with high visibility to the human eye, and light easily leaks due to its spectral characteristics. The thickness of the liquid crystal such as the frame is preferably based on the green pixel.

  According to the present invention, a color filter substrate excellent in flatness can be formed with few steps with high accuracy, and a liquid crystal display device including the color filter substrate can be provided.

  In addition, according to the present invention, a color filter substrate for a high-quality liquid crystal display device and a liquid crystal display device in consideration of electrical characteristics such as relative permittivity are provided. In addition, a high-quality liquid crystal display device is provided by using a light-shielding layer mainly composed of a plurality of organic pigments and a zinc halide phthalocyanine having excellent electrical and optical characteristics as a main colorant for a green pixel. be able to.

It is sectional drawing which shows the color filter board | substrate which concerns on one Embodiment of this invention. It is sectional drawing which shows the color filter board | substrate which concerns on other embodiment of this invention. It is sectional drawing which shows the other part of the color filter board | substrate which concerns on one Embodiment of this invention. It is a fragmentary sectional view which expands and shows the part enclosed with the circle of the broken line of FIG. It is a characteristic view which shows the spectral characteristic of the green pixel containing a halogenated zinc phthalocyanine pigment. It is a top view which shows the color filter board | substrate which concerns on one Embodiment of this invention. It is a characteristic view which shows the relationship between a base film thickness and the film thickness of the laminated part of the colored layer on a base. It is a top view which shows the color filter board | substrate which concerns on other embodiment of this invention. It is a characteristic view showing the relationship between the film thickness of the black matrix and the protrusion height of the colored pixel end portion superimposed on the black matrix. It is sectional drawing which shows the pattern edge shape and inclination | tilt angle of the coloring pixel of a thick film thickness. It is sectional drawing which shows the pattern edge shape and inclination angle of the coloring pixel of a thin film thickness. 6 is a plan view showing a color filter substrate according to Embodiment 2. FIG. 6 is a plan view showing green pixels of a color filter substrate according to Embodiment 2. FIG. 6 is a cross-sectional view illustrating green pixels of a color filter substrate according to Embodiment 2. FIG. 6 is a cross-sectional view showing a green pixel of a color filter substrate according to Example 3. FIG. 6 is a cross-sectional view showing a color filter substrate according to Example 4. FIG. 10 is a cross-sectional view illustrating a color filter substrate according to Example 5. FIG. 10 is a cross-sectional view illustrating a liquid crystal display device according to Example 6. FIG. 7 is a partial cross-sectional view showing a liquid crystal display device according to Example 6. FIG. 10 is a cross-sectional view illustrating a liquid crystal display device according to Example 7. FIG.

  Hereinafter, embodiments of the present invention will be described.

  A color filter substrate according to an embodiment of the present invention includes a light shielding layer disposed on the outer periphery of an effective display area on a transparent substrate, and a plurality of colored pixels including a green pixel, a spacer, and a first retardation layer Is formed in the effective display area, and is applied to a transflective liquid crystal display device. The transflective liquid crystal display device includes a reflective portion that receives and reflects light incident from the observer side, such as external light and front light, and a transmission that transmits light from the backlight disposed on the back surface of the liquid crystal display device. There is a part, and the colored pixel also has a reflection part and a transmission part for each pixel.

  In the following description, the light shielding layer and the frame portion are synonymous and mean a frame-shaped light shielding pattern on the outer periphery of the effective display area.

  In the color filter substrate according to the present embodiment, a concave portion is formed in each reflective portion of the colored pixel, and a retardation layer is provided in the concave portion. The retardation layer has a function of compensating for the optical path difference between the reflection portion and the transmission portion described above. In other words, linearly polarized light, which is incident light (external light) transmitted through a polarizing plate externally attached to the liquid crystal display element, is converted into circularly polarized light, and a light-reflective electrode (or reflective) disposed inside the liquid crystal display element. The light reflected by the plate) returns to substantially linearly polarized light and is used as outgoing light.

  Specifically, the retardation layer is a reflective liquid crystal display device that uses a light-reflecting reflective electrode, and changes the phase of polarized light by a quarter wavelength or a half wavelength, and makes one round trip in the thickness direction of the liquid crystal layer. (Reflection) has a function of making linearly polarized light with 90 degrees different directions.

  Further, after adjusting the absorption axis of the polarizing plate and the slow axis of the retardation layer, a half-wave retardation layer may be used to rotate the polarization by 90 degrees or 270 degrees. For example, in an IPS mode liquid crystal display device that is aligned parallel to the substrate surface and rotated in the substrate surface direction, the absorption axis of the polarizing plate and the slow axis of the retardation layer are shifted by 22.5 degrees or 67.5 degrees, By using a half-wave retardation layer, incident light converted into linearly polarized light can be effectively rotated by 90 degrees. By applying the retardation layer to the reflective portion of the transflective liquid crystal display device with the above-described configuration, the optical path difference between the reflective portion and the transmissive portion can be adjusted and the phase can be compensated. Effectively rotating the polarization by 90 ° means that the phase difference layer formed in the reflection portion 90 radiates the incident light, including accuracy such as the transmission axis of the polarizing plate, the alignment axis of the liquid crystal, and the tilt angle of the liquid crystal. ° Means polarization rotation.

  Assuming the liquid crystal alignment in the VA mode or TN mode liquid crystal display mode, the angle formed by the slow axis of the quarter-wave retardation layer and the absorption axis (or transmission axis) of the polarizing plate is about 45 degrees. be able to.

  In the color filter substrate according to the present embodiment, the spacer is a structure having a trapezoidal or columnar cross section formed in order to make the thickness of the liquid crystal layer in the transmissive portion in the effective display region uniform, and the thickness of the liquid crystal layer. And almost the same height. In addition to this spacer, a sub-spacer having a low height can be formed in the effective display area and on the light shielding layer. These spacers may be formed on the color filter using, for example, an alkali-soluble photosensitive acrylic resin, but a single layer to three layers of colored layers (in the case of including other colors such as yellow pixels and white pixels, 4 In the case of forming a colored pixel, the manufacturing process can be simplified.

  Normally, the liquid crystal panel is formed by adhering a color filter substrate and an array substrate on which active elements for driving the liquid crystal are formed facing each other so as to sandwich the liquid crystal layer. The spacer height must include the bonding margin at this time. The spacer height is the height from the surface at the center of the pixel adjacent to the spacer to the top of the spacer.

  Hereinafter, from the viewpoint of the thickness of the cross section, a colored layer is formed by simply forming a colored layer at a portion where a transmissive portion is formed, a recessed colored layer at a thin portion of a reflective portion, and a colored layer laminated as a spacer. Expressed separately from the colored layer. These colored layers can be manufactured by the same coating process and photolithography process.

  Also, a coating layer applied on a transparent substrate with a photosensitive coloring composition for forming a pixel of a color filter, or a single-layer layer with a photosensitive coloring composition is used as a coloring layer, and the coloring layer is used for publicly known. A pattern formed by this photolithography technique is called a colored pixel.

  The film thickness of the colored pixel refers to the height from the surface of the transparent substrate to the surface at the center of the colored pixel (in this case, the pixel center in the colored layer having no recess). The ratio of the thickness of the concave colored layer to the thickness of the colored layer (portion where no concave portion is formed) is preferably in the range of 1/2 to 1/4. It should be noted that the thickness of the concave colored layer having a thickness ratio of 1/2 is 1/2 within an error range of ± 0.2 μm with respect to the thickness of the colored layer. The original color display in consideration of the optical path difference between the transmissive part and the reflective part can be obtained by setting the ratio of the thickness of the colored layer of the concave part to the thickness of the colored layer (the part where the concave part is not formed) to be approximately ½. Can do.

  The reflection part is for observing in a bright environment such as outdoors, and brightness is important. Although it is desirable that the chromaticity areas of the transmissive part and the reflective part coincide with each other, it is sufficient to recognize that the color is on when the brightness is most important. For example, the reflective display has a film thickness ratio of 1/3 or 1/4 in an application in which “brightness” is more important than color matching of the transmissive portion display (for example, outdoor use where sunlight is present). Therefore, it is desirable to use a color with high brightness.

  Assuming that the chromaticity range of the transmissive part in static display (still image) is about 70% of the standard NTSC ratio, the NTSC ratio of the reflective part is about 35 to ¼ when the film thickness is 1/4 (with twice transmission). It becomes about 40%. If the NTSC ratio is 35 to 40%, it can be easily recognized that it is colored, but if it is much less than this, it is difficult to recognize that it is colored. Therefore, it is desirable that the film thickness of the reflecting portion is ¼ or more at which the NTSC ratio is about 35 to 40%.

  The color visibility in moving image gradation display tends to be lower than that in still image display. Although there are individual differences depending on the user (observer), it is easy to recognize that the thickness of the concave colored layer that is 1/4 of the colored layer thickness is a color display when moving image gradation display is performed. The film thickness is almost the lower limit. The height of the overlapping portion of adjacent colored pixels (hereinafter referred to as a protrusion) is the height from the top of the protrusion to the surface at the center of the colored pixel. The colored pixels of a plurality of colors are expressed as blue pixels, red pixels, green pixels, yellow pixels, white pixels (transparent pixels), and the like.

  In this specification, the configuration of a plurality of colored pixels including a light shielding layer is referred to as a color filter, and a color filter formed on a transparent substrate such as glass is referred to as a color filter substrate. The colored layers stacked as spacers are referred to as a red stacked portion, a green stacked portion, and a blue stacked portion, respectively. In this specification, the substantially same film thickness can be controlled by the manufacturing process in the formation of the light shielding layer and the colored layer. For example, the manufacturing margin in the color filter manufacturing process with respect to the set film thickness. The film thickness is within ± 0.2 μm.

  The relative dielectric constant referred to in the description of the present specification is based on the assumption that the frequency used for driving the liquid crystal is 50 Hz to 500 Hz and the measurement is performed at room temperature.

  In the color filter substrate according to another embodiment of the present invention, a cell gap adjusting layer is disposed on the retardation layer for the purpose of adjusting the thickness of the liquid crystal layer in the transmission part and the reflection part described above. In this case, the difference in height from the surface of the cell gap adjusting layer and the surface of the colored pixel where no recess is formed can be approximately ½ of the thickness of the liquid crystal layer when the liquid crystal display device is constructed. . Note that approximately 1/2 of the thickness of the liquid crystal layer may vary within a range of 10% of the thickness of the liquid crystal layer, and within ± 0.2 μm that is the manufacturing margin in the manufacturing process of the color filter. It is desirable to be. In the following description of the present specification, “substantially the same film thickness” similarly refers to a film thickness that increases or decreases within a manufacturing margin of ± 0.2 μm in the color filter manufacturing process.

  The cell gap adjusting layer may be an insulating material transparent in the visible range, but is preferably a light scattering layer imparted with light scattering properties. In other words, the light scattering layer serves as a diffuser for imparting diffusibility to the emitted light, making the light from the liquid crystal display device that enters the observer's eyes look like paper white and displaying with good visibility.

  In a color filter substrate according to still another embodiment of the present invention, a pedestal and a black matrix can be arranged. The pedestal and the black matrix are formed of the same light shielding material as that of the light shielding layer. The pedestal is arranged almost corresponding to the position of an active element such as a TFT when a liquid crystal display device configured by bonding a color filter substrate and an array substrate is assumed. Spacers that are arranged on the substrate side and make the cell gap uniform can be arranged on the pedestal. The pedestal only needs to have an area that roughly covers the active element in plan view. The black matrix formed as necessary refers to a light shielding pattern in a lattice shape or a stripe shape provided in the display region for the purpose of improving the contrast of the liquid crystal display device. The pedestal and the black matrix may be formed in one connected pattern with the same film thickness using one photomask.

  The spacer can be disposed at the center of the colored pixel. In this configuration, a light-reflective reflective film or electrode is formed on the array substrate facing the color filter substrate in the central portion, or a pedestal is not formed at this spacer position if it is a transmissive portion. good. When this central portion is a reflection portion, the spacer can be disposed on the cell gap adjustment layer, and the sum of the spacer height and the cell gap adjustment layer corresponds to the thickness of the liquid crystal layer in the transmission portion.

  The thickness of the pedestal and the black matrix is preferably thinner than the thickness of the light shielding layer. The method of forming these thinly can be adjusted by adjusting the shape of the halftone mask used for exposure, the graytone mask, the opening of the mask, etc., in addition to the adjustment in the process such as the development step and the heat treatment step.

  FIG. 1 is a diagram showing a cross section of a part of a color filter substrate according to an embodiment of the present invention, and corresponds to a cross section A-A ′ of a plan view shown in FIG. 6 described later. In FIG. 1, a light-shielding layer 2 made mainly of an organic pigment is disposed on the outer peripheral frame portion of the display area on the transparent substrate 1, and a red pixel 3R (not shown), a green pixel 3G, and a blue pixel 3B are displayed in the display area. Three colored pixels (not shown) are formed.

  The colored pixel (3G in FIG. 1) includes a reflective portion and a transmissive portion, and a concave portion 10 is formed in the reflective portion. A retardation layer 11 is formed in the recess 10, and a light scattering layer (cell gap adjustment layer) 12 is formed on the retardation layer 11. A retardation layer 11 ′ is also disposed on the frame-shaped light shielding layer 2. A transparent conductive film 9 is disposed so as to cover these colored pixels and the light scattering layer 12. The formation position of the transparent conductive film 9 is not limited to the light scattering layer 12 but may be provided under the light scattering layer 12. Further, it can be formed on the surface of the transparent substrate 1 or a black matrix surface described later.

  In the color filter substrate shown in FIG. 1, the light scattering layer 12 is a layer in which single or plural kinds of amorphous fine particles 13 are dispersed in a matrix resin 14 having different refractive indexes. The cell gap adjusting layer functioning as the light scattering layer 12 is an optical functional film that scatters incident light to give a paper white-like effect to the eyes of the observer. The matrix resin 14 may be a transparent resin that has heat resistance and visible range transparency. The film thickness of the light scattering layer is preferably in the range of about 1 μm to 3 μm due to the relationship between the amorphous fine particle diameter, the wavelength of light, and the suitability in the manufacturing process.

  In the color filter substrate shown in FIG. 2, a cell gap adjusting layer 15 made of a transparent resin is formed as a cell gap adjusting layer instead of the light scattering layer 12 shown in FIG. The cell gap adjustment layer 15 is disposed for the purpose of adjusting the optical path difference between the transmission part and the reflection part. Therefore, a resin material having at least high transparency to visible light and heat resistance necessary for the liquid crystal panel process can be used for the cell gap adjustment layer 15. A transparent conductive film 9 is disposed so as to cover these colored pixels and the cell gap adjusting layer 15.

  In the color filter substrate shown in FIG. 2, the cell gap adjustment layer 15 ′ is also disposed on the frame-shaped light shielding layer 2, and the total thickness of the cell gap adjustment layer 15 ′ and the light shielding layer 2 in this portion is as follows. It is substantially equal to the film thickness of the green pixel 3G. 2 corresponds to an E-E ′ cross section of the plan view shown in FIG. 6 described later.

  FIG. 3 is a cross-sectional view showing another part of the color filter substrate according to the embodiment of the present invention, and corresponds to a B-B ′ cross section of the plan view shown in FIG. 6 described later. In FIG. 3, the light-shielding layer 2 containing a black color material in the outer peripheral frame portion of the display area on the transparent substrate 1 is a three-color colored pixel including a red pixel 3R, a green pixel 3G, and a blue pixel 3B in the display area. Are formed. The thickness of the light shielding layer 2 and the thickness of the colored pixels are substantially the same. A pedestal 4 made of the same material as the light shielding layer 2 is formed on the transparent substrate 1 at the boundary between the red pixel 3R and the green pixel 3G. On the pedestal 4, a red laminated portion 5R, a green laminated portion 5G, and A spacer 5 made of a stack of blue stacked portions 5B is formed.

  On the transparent substrate 1 at the boundary between the green pixel 3G and the blue pixel 3B, a pedestal 4 'made of the same material as the light shielding layer 2 is formed, on which the spacer 5 is not formed. The pedestal 4 ′ in which the spacer 5 is not formed is provided for the purpose of adjusting the aperture ratio of the red pixel 3 </ b> R, the green pixel 3 </ b> G, and the blue pixel 3 </ b> B and shielding light from active elements such as TFTs.

  On the light shielding layer 2, for example, a sub-spacer 6 having a two-layer structure, which is lower in height than the spacer 5 having a three-layer structure, is disposed.

  A transparent conductive film 9 is disposed on the surface having the above configuration.

  The pedestal 4 is thinner than the light shielding layer 2 and has a film thickness of 0.4 μm or more and 1.0 μm or less. When the film thickness of the pedestal 4 is less than 0.4 μm, it is difficult to obtain a stable film thickness when the pedestal 4 is formed by photolithography. On the other hand, when the thickness exceeds 1.0 μm, the thickness of the laminated portion laminated thereon becomes thin, a sudden change in film thickness occurs between the pixels, and the laminated portion becomes unstable.

  A TFT substrate is disposed opposite to the color filter substrate configured as described above, and a liquid crystal display device is configured by interposing a liquid crystal layer between the color filter substrate and the TFT substrate. The thickness and the height of the spacer formed on the pedestal are substantially equal. The height h of the spacer 5 is the thickness of the portion protruding from the surface of the colored pixels 3R, 3G, 3B in the stack of the red stacked portion 5R, the green stacked portion 5G, and the blue stacked portion 5B. The height H of the spacer 5 is preferably a height obtained by adding a margin of about 0.1 μm in the manufacturing process of the liquid crystal cell to the thickness of the liquid crystal layer.

  4 is an enlarged view of a portion surrounded by a broken-line circle of the color filter substrate shown in FIG. A portion surrounded by a broken-line circle is an overlapping portion of the blue pixel 3B and the green pixel 3G. A transparent conductive film 9 is disposed so as to cover the blue pixel 3B and the green pixel 3G. The overlapping portion of the blue pixel 3B and the green pixel 3G is a protrusion 7 that protrudes with respect to the surface of the pixel. If the height d of the protrusion 7 is too high, the flatness of the pixel is impaired. It is desirable that it is 25 μm or less. A planarizing film (protective film) may be formed between the transparent conductive film 9 and the colored pixels using a transparent resin.

  FIG. 6 is a diagram showing a planar arrangement of the light shielding layer 2, the pedestals 4, 4 ′, the spacer 5, the sub-spacer 6, and the light scattering layer (cell gap adjustment layer) 12 in the color filter substrate. The A-A ′ cross section in FIG. 6 corresponds to FIG. 1, and the B-B ′ cross section corresponds to FIG. 3.

  Next, the material which comprises the color filter substrate comprised as mentioned above is demonstrated.

  In the color filter substrate according to the present embodiment, the transparent conductive film 9 is formed on the color filter, and there is no electrical contact between the color filter and the liquid crystal layer. Therefore, the light shielding layer 2, the red pixel 3R, and the green pixel 3G. It is also possible to use a material having a high relative dielectric constant such as carbon for the color material of the blue pixel 3B and the base 4. Here, as a color material having a low relative dielectric constant, an organic pigment that can be used for the light shielding layer 2, the red pixel 3R, the green pixel 3G, the blue pixel 3B, the pedestal 4, the spacer 5, or a liquid crystal alignment control protrusion. Listed below. However, since the spacer, the alignment control structure described later, the alignment control protrusion, and the like are disposed in contact with the liquid crystal, it is desirable to form the spacer with a material having a low relative dielectric constant. The color material to be contained in the light shielding layer may be carbon alone, a mixture of various organic pigments, or carbon may be added to the organic pigment. Carbon that can be added may be carbon particles that have been subjected to resin coating or surface treatment in order to lower the relative dielectric constant. The alignment control protrusion is called a rib (linear) or a rivet, and is a protrusion formed on the color filter or the transparent conductive film for the purpose of controlling the alignment of the liquid crystal.

(Organic pigment)
Examples of red pigments include C.I. I. Pigment Red 7, 9, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 3, 97, 122, 123, 146, 149, 168, 177, 178, 179, 180, 184, 185, 187, 192, 200, 202, 208, 210, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 246, 254, 255, H.264, 272, 279, etc. can be used.

  Examples of yellow pigments include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125, 126, 127, 128, 129, 137, 138, 139, 144, 146, 147, 148, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 1 73, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 193, 194, 199, 213, 214 and the like.

  Examples of blue pigments include C.I. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64, 80, etc., among which C.I. I. Pigment Blue 15: 6 is preferred.

  Examples of purple pigments include C.I. I. Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, 50, etc. can be used. I. Pigment Violet 23 is preferred.

  Examples of the green pigment include C.I. I. Pigment Green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55, 58, etc. can be used. In C.I. I. Pigment Green 58 is preferred.

  Hereinafter, C.I. I. In the description of Pigment pigment types, it may be simply abbreviated as PB (Pigment Blue), PV (Pigment Violet), PR (Pigment Red), PY (Pigment Yellow), PG (Pigment Green), or the like.

  The above-described PG58 is called zinc halide phthalocyanine, and its production example is shown in [Pigment production example G2] described later. PG58 has a smaller dielectric constant than the halogenated copper phthalocyanine, which is PG36, and can form a green pixel with high brightness. PG58 and PG36 are organic pigments having substantially the same structure except that the central metal is zinc and copper, but PG58 tends to be smaller in electrical characteristics including variations in dielectric constant.

  Despite the similarity in structure, the reason why PG58 is suitable for the present invention, according to the knowledge of the present inventors, is demonstrated from the following optical measurement (measurement of birefringence Δn of green pigment). Can do. In addition, the one where the solid ratio of organic pigments, such as a halogenated zinc phthalocyanine in a coloring composition, has a tendency to reduce a dielectric constant is preferable.

  In order to reduce the stray capacitance caused by the color filter that hinders the liquid crystal drive, it is preferable to decrease the pigment ratio and increase the resin ratio. Therefore, it is preferable to increase the thickness of the light shielding layer and the colored pixels as in the embodiment of the present invention.

  As described above, a green organic pigment dispersion (or green pixel) of copper halide phthalocyanine conventionally used for a green pixel has a large phase difference in the negative direction. It is necessary to compensate for this by adjusting the phase difference in the zero direction. Further, as shown in FIG. 5, green pixels having halogenated copper phthalocyanine as a main pigment tend to be inferior in transmittance and lightness to green pixels having halogenated zinc phthalocyanine as a main pigment. It is particularly preferable to use a green pigment of zinc halide phthalocyanine for the green pixel.

[Measurement of birefringence Δn of green pigment]
As is well known, the value of the dielectric constant is approximately equal to the square of the refractive index. In other words, the dielectric constant resulting from electronic polarization is proportional to the square of the refractive index.

  From this point of view, the difference in polarization between PG58 and PG36 was clarified by measuring refractive indexes Nx, Ny, and Nz on the orthogonal coordinate system X-axis, Y-axis, and Z-axis, respectively. In order to make the measurement sample have a configuration close to the green coloring layer actually used, a pigment dispersion (for example, GP-4) shown in Table 3 below was applied on a glass substrate to a thickness of 1 μm and dried at 230 ° C. Things were used.

  The main pigment G2 of the pigment dispersion of GP-4 shown in Table 3 below is PG58. A pigment dispersion in which the first pigment G2 of GP-4 is replaced with PG36 is denoted as GP-5. For the measurement, a spectroscopic ellipsometer M-220 (manufactured by JASCO) was used to measure Nx, Ny, and Nz, and Δn was calculated from the following equation. The measurement wavelength was 550 nm.

Δn = [(Nx + Ny) / 2] −Nz
From Table 1 below, the coating film of the green pigment dispersion GP-4 mainly containing the halogenated zinc phthalocyanine (PG58) rather than the green pigment dispersion GP-5 mainly containing the halogenated copper phthalocyanine (PG36). It can be understood that the absolute value of Δn is smaller and the polarization is smaller. The inventors of the present invention have a colored coating film in which halogenated copper phthalocyanine is dispersed, which tends to exhibit a large phase difference in the negative direction and is difficult to align the phase difference of colored pixels, whereas a colored coating film in which zinc halide phthalocyanine is dispersed. Indicates substantially zero or a slight amount of phase difference in the positive direction, and is found to be suitable for aligning the phase differences of the colored pixels.

(Manufacture of organic pigment dispersion)
Various methods can be adopted as a method for producing a dispersion of an organic pigment, and an example is shown below.

  First, pigments, solvents, pigment dispersants (including dye derivatives) and / or dispersion aids, surfactants, and in some cases, polymers and monomers are weighed in predetermined amounts, and subjected to a dispersion treatment step to disperse the pigments. A pigment dispersion is obtained. In this dispersion treatment step, for example, a paint conditioner, a bead mill, a ball mill, a roll mill, a stone mill, a jet mill, a homogenizer, or the like can be used. By carrying out this dispersion treatment, the pigment is made fine, so that the coating characteristics of the photosensitive resin composition using the pigment dispersion are improved.

  When dispersing the pigment, the alkali-soluble resin, the pigment derivative, or the like may be used in combination as appropriate. For example, when the dispersion treatment is performed using a bead mill, glass beads or zirconia beads having a diameter of 0.1 mm to several mm are preferably used. The temperature during the dispersion treatment is usually 0 ° C. or higher, preferably room temperature or higher, and is usually set to 100 ° C. or lower, preferably 80 ° C. or lower. The dispersion time varies depending on the composition of the pigment dispersion (pigment, solvent, dispersant, etc.) and the size of the apparatus such as the bead mill.

(Adjusting the phase difference of colored pixels)
The colored pixel can finely adjust the phase difference particularly from the viewpoint of the thickness direction phase difference. Increase or decrease the phase difference by various methods such as pigment type, pigment dispersion method, dispersant, finer pigment, and melamine resin, styrene resin, organic compound having benzyl group added as a retardation modifier. be able to. Melamine resin can be adjusted in the direction of increasing the phase difference, and styrene resin can be used to decrease the phase difference.

  For example, as an example of a styrene resin, a styrene-acrylic acid copolymer having a weight average molecular weight of about 7000 is contained in 5 to 20 parts in 40 parts of an acrylic resin solution of a photosensitive coloring composition, so that a red pixel or a green pixel The thickness direction retardation such as can be adjusted to a small value of 10 nm or less. The addition ratio of the retardation adjusting agent in the acrylic resin solution can be appropriately adjusted. In a green pixel, a zinc halide phthalocyanine pigment is preferable because its thickness direction phase difference tends to approach zero.

  Note that the technique described in Japanese Patent No. 43066736 can be applied to adjust the phase difference between the colored pixels.

  Thickness direction retardation can be measured with respect to the board | substrate which apply | coated and formed the coating film of the colored layer or retardation layer, for example using a phase difference measuring apparatus (RETS-100 by Otsuka Electronics Co., Ltd.).

(Dispersant / dispersant aid)
A polymer dispersant is preferably used as the pigment dispersant because it is excellent in dispersion stability over time. Examples of the polymer dispersant include a urethane dispersant, a polyethyleneimine dispersant, a polyoxyethylene alkyl ether dispersant, a polyoxyethylene glycol diester dispersant, a sorbitan aliphatic ester dispersant, and an aliphatic modified polyester. And the like, and the like. Among these, a dispersant composed of a graft copolymer containing a nitrogen atom is particularly preferable from the viewpoint of developability as the light-shielding photosensitive resin composition of the present invention containing a large amount of pigment.

  Specific examples of these dispersants are trade names of EFKA (manufactured by EFKA Chemicals Beebuy (EFKA)), Disperbik (manufactured by BYK Chemie), Disparon (manufactured by Enomoto Kasei), SOLPERSE (manufactured by Lubrizol), KP (Manufactured by Shin-Etsu Chemical Co., Ltd.), polyflow (manufactured by Kyoeisha Chemical Co., Ltd.) and the like. 1 type may be used for these dispersing agents, and 2 or more types can be used together by arbitrary combinations and a ratio.

  As the dispersion aid, for example, a pigment derivative or the like can be used. Examples of the dye derivative include azo, phthalocyanine, quinacridone, benzimidazolone, quinophthalone, isoindolinone, dioxazine, anthraquinone, indanthrene, perylene, perinone, diketopyrrolopyrrole. And oxinophthalone derivatives are preferred.

  Examples of the substituent of the dye derivative include a sulfonic acid group, a sulfonamide group and a quaternary salt thereof, a phthalimidomethyl group, a dialkylaminoalkyl group, a hydroxyl group, a carboxyl group, and an amide group directly on the pigment skeleton or an alkyl group and an aryl group. And those bonded via a heterocyclic group or the like. Of these, sulfonic acid groups are preferred. In addition, a plurality of these substituents may be substituted on one pigment skeleton.

  Specific examples of the dye derivatives include phthalocyanine sulfonic acid derivatives, quinophthalone sulfonic acid derivatives, anthraquinone sulfonic acid derivatives, quinacridone sulfonic acid derivatives, diketopyrrolopyrrole sulfonic acid derivatives, and dioxazine sulfonic acid derivatives. .

1 type may be used for the above dispersion adjuvant and pigment | dye derivative | guide_body, and 2 or more types may be used together by arbitrary combinations and a ratio. The pigment derivatives used in Examples described later are shown in Table 2 below.

(Transparent resin)
The photosensitive coloring composition used as the light-shielding layer or the colored layer further contains a polyfunctional monomer, a photosensitive resin or a non-photosensitive resin, a polymerization initiator, a solvent and the like in addition to the pigment dispersion. Highly transparent organic resins that can be used in the present invention, such as photosensitive resins and non-photosensitive resins, are collectively referred to as transparent resins.

  The transparent resin includes a thermoplastic resin, a thermosetting resin, and a photosensitive resin. Examples of the thermoplastic resin include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane resin, and polyester resin. And acrylic resins, alkyd resins, polystyrene resins, polyamide resins, rubber resins, cyclized rubber resins, celluloses, polybutadiene, polyethylene, polypropylene, polyimide resins, and the like. Examples of the thermosetting resin include epoxy resins, benzoguanamine resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, melamine resins, urea resins, and phenol resins. As the thermosetting resin, a resin obtained by reacting the following melamine resin with an isocyanate group-containing compound may be used.

(Alkali-soluble resin)
For the light shielding layer, light scattering layer, colored layer, and cell gap regulating layer used in the present invention, it is preferable to use a photosensitive resin composition capable of forming a pattern by photolithography. These transparent resins are desirably resins imparted with alkali solubility. The alkali-soluble resin is not particularly limited as long as it is a resin containing a carboxyl group or a hydroxyl group. Examples include epoxy acrylate resins, novolac resins, polyvinyl phenol resins, acrylic resins, carboxyl group-containing epoxy resins, carboxyl group-containing urethane resins, and the like. Of these, epoxy acrylate resins, novolak resins, and acrylic resins are preferable, and epoxy acrylate resins and novolak resins are particularly preferable.

(acrylic resin)
Examples of the transparent resin that can be used in the present invention include the following acrylic resins.

  Acrylic resin is, for example, (meth) acrylic acid; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, t-butyl (meth) acrylate pencil Alkyl (meth) acrylates such as (meth) acrylate and lauryl (meth) acrylate; hydroxyl-containing (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; ethoxyethyl (meth) acrylate and glycidyl (meta ) Ether group-containing (meth) acrylates such as acrylates; and alicyclic (meth) acrylates such as cyclohexyl (meth) acrylates, isobornyl (meth) acrylates, dicyclopentenyl (meth) acrylates, etc. Polymers.

  In addition, the monomer mentioned above can be used individually or in combination of 2 or more types. Further, it may be a copolymer of a compound such as styrene, cyclohexylmaleimide, and phenylmaleimide copolymerizable with these monomers.

  Further, for example, a copolymer obtained by copolymerizing a carboxylic acid having an ethylenically unsaturated group such as (meth) acrylic acid, and a compound containing an epoxy group and an unsaturated double bond such as glycidyl methacrylate are obtained. Reacting or adding a carboxylic acid-containing compound such as (meth) acrylic acid to a polymer of an epoxy group-containing (meth) acrylate such as glycidyl methacrylate or a copolymer thereof with other (meth) acrylate Thus, a resin having photosensitivity can be obtained.

  Furthermore, a resin having photosensitivity can also be obtained by reacting a polymer having a hydroxyl group of a monomer such as hydroxyethyl methacrylate with a compound having an isocyanate group such as methacryloyloxyethyl isocyanate and an ethylenically unsaturated group. Can be obtained.

  In addition, as described above, it is possible to react a copolymer such as hydroxyethyl methacrylate having a plurality of hydroxyl groups with a polybasic acid anhydride to introduce a carboxyl group into the copolymer to obtain a resin having a carboxyl group. I can do it. The manufacturing method is not limited to the method described above.

  Examples of acid anhydrides used in the above reaction include, for example, malonic acid anhydride, succinic acid anhydride, maleic acid anhydride, itaconic acid anhydride, phthalic acid anhydride, tetrahydrophthalic acid anhydride, hexahydrophthalic acid anhydride , Methyltetrahydrophthalic anhydride, trimellitic anhydride and the like.

  It is preferable that the solid content acid value of the acrylic resin described above is 20 to 180 mgKOH / g. When the acid value is less than 20 mgKOH / g, the development speed of the photosensitive resin composition is too slow, and the time required for development increases, and the productivity tends to be inferior. On the other hand, when the solid content acid value is larger than 180 mgKOH / g, on the contrary, the development speed is too high, and there is a tendency that pattern peeling or pattern chipping after development occurs.

  Furthermore, when the said acrylic resin has photosensitivity, it is preferable that the double bond equivalent of this acrylic resin is 100 or more, More preferably, it is 100-2000, Most preferably, it is 100-1000. If the double bond equivalent exceeds 2000, sufficient photocurability may not be obtained.

(Photopolymerizable monomer)
Examples of photopolymerizable monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, polyethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylol Various acrylic and methacrylic acid esters such as propane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, melamine (meth) acrylate, epoxy (meth) acrylate, (meth) Examples include acrylic acid, styrene, vinyl acetate, (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, and acrylonitrile.

  Moreover, it is preferable to use the polyfunctional urethane acrylate which has the (meth) acryloyl group obtained by making polyfunctional isocyanate react with the (meth) acrylate which has a hydroxyl group. The combination of the (meth) acrylate having a hydroxyl group and the polyfunctional isocyanate is arbitrary and is not particularly limited. Moreover, one type of polyfunctional urethane acrylate may be used alone, or two or more types may be used in combination.

(Photopolymerization initiator)
Examples of the photopolymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- Acetophenone compounds such as hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl Benzoin compounds such as dimethyl ketal, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4 ' Benzophenone compounds such as methyldiphenyl sulfide, thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, 2,4,6- Trichloro-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- ( p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-pienyl-4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) -6-styryl s-triazine, 2- (naphth-1-yl) -4,6-bis (trichloromethyl) -s-tri Gin, 2- (4-methoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-trichloromethyl- (piperonyl) -6-triazine, 2,4-trichloro Triazine compounds such as methyl (4′-methoxystyryl) -6-triazine, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], O- (acetyl) Oxime ester compounds such as -N- (1-phenyl-2-oxo-2- (4'-methoxy-naphthyl) ethylidene) hydroxylamine, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2, Phosphine compounds such as 4,6-trimethylbenzoyldiphenylphosphine oxide, 9,10-phenanthrenequinone,
Examples include quinone compounds such as camphorquinone and ethyl anthraquinone, borate compounds, carbazole compounds, imidazole compounds, titanocene compounds, and the like. Oxime derivatives (oxime compounds) are effective in improving sensitivity. These can be used singly or in combination of two or more.

(Sensitizer)
It is preferable to use a polymerization initiator and a photosensitizer in combination. As a sensitizer, α-acyloxy ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10-phenanthrenequinone, camphorquinone, ethylanthraquinone, 4,4′-diethylisophthalophenone, A compound such as 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 4,4′-diethylaminobenzophenone may be used in combination.

  The sensitizer can be contained in an amount of 0.1 to 60 parts by mass with respect to 100 parts by mass of the photopolymerization initiator.

(Ethylenically unsaturated compounds)
The photopolymerization initiator is preferably used together with an ethylenically unsaturated compound. The ethylenically unsaturated compound means a compound having at least one ethylenically unsaturated bond in the molecule. Among them, it is a compound having two or more ethylenically unsaturated bonds in the molecule from the viewpoints of polymerizability, crosslinkability, and the accompanying difference in developer solubility between exposed and non-exposed areas. Is preferred. The unsaturated bond is more preferably a (meth) acrylate compound derived from a (meth) acryloyloxy group.

  Examples of the compound having one or more ethylenically unsaturated bonds in the molecule include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, isocrotonic acid, maleic acid, itaconic acid, citraconic acid, and alkyl esters thereof. , (Meth) acrylonitrile, (meth) acrylamide, styrene and the like. Typical examples of compounds having two or more ethylenically unsaturated bonds in the molecule include esters of unsaturated carboxylic acids and polyhydroxy compounds, (meth) acryloyloxy group-containing phosphates, hydroxy (meta ) Urethane (meth) acrylates of acrylate compounds and polyisocyanate compounds, and epoxy (meth) acrylates of (meth) acrylic acid or hydroxy (meth) acrylate compounds and polyepoxy compounds.

  You may add the said photopolymerization initiator, a sensitizer, and an ethylenically unsaturated compound to the composition containing the polymeric liquid crystal compound used for formation of the phase difference layer mentioned later.

(Multifunctional thiol)
The photosensitive coloring composition can contain a polyfunctional thiol that functions as a chain transfer agent. The polyfunctional thiol may be a compound having two or more thiol groups. For example, hexanedithiol, decanedithiol, 1,4-butanediol bisthiopropionate, 1,4-butanediol bisthioglycolate, ethylene Glycol bisthioglycolate, ethylene glycol bisthiopropionate, trimethylolpropane tristhioglycolate, trimethylolpropane tristhiopropionate, trimethylolpropane tris (3-mercaptobutyrate), pentaerythritol tetrakisthioglycolate, Pentaerythritol tetrakisthiopropionate, trimercaptopropionic acid tris (2-hydroxyethyl) isocyanurate, 1,4-dimethylmercaptobenzene, 2,4,6-trimercap -s- triazine, 2- (N, N- dibutylamino) -4,6-dimercapto -s- triazine.

  These polyfunctional thiols can be used alone or in combination. The polyfunctional thiol can be used in an amount of 0.2 to 150 parts by mass, preferably 0.2 to 100 parts by mass with respect to 100 parts by mass of the pigment in the photosensitive coloring composition.

(Storage stabilizer)
The photosensitive coloring composition can contain a storage stabilizer in order to stabilize the viscosity with time of the composition. Examples of the storage stabilizer include quaternary ammonium chlorides such as benzyltrimethyl chloride and diethylhydroxyamine, organic acids such as lactic acid and oxalic acid, and organic acids such as methyl ether, t-butylpyrocatechol, triethylphosphine, and triphenylphosphine. Examples thereof include phosphine and phosphite. The storage stabilizer can be contained in an amount of 0.1 to 10 parts by mass with respect to 100 parts by mass of the pigment in the photosensitive coloring composition.

(Adhesion improver)
The photosensitive coloring composition may contain an adhesion improving agent such as a silane coupling agent in order to improve the adhesion to the substrate. Examples of the silane coupling agent include vinyl silanes such as vinyltris (β-methoxyethoxy) silane, vinylethoxysilane, and vinyltrimethoxysilane, (meth) acrylsilanes such as γ-methacryloxypropyltrimethoxysilane, β- (3 , 4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) methyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ) Epoxysilanes such as methyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β ( Aminoethyl) γ-aminopro Lutriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N Examples include aminosilanes such as -phenyl-γ-aminopropyltriethoxysilane, thiosilanes such as γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane. The silane coupling agent can be contained in an amount of 0.01 to 100 parts by mass with respect to 100 parts by mass of the pigment in the photosensitive coloring composition.

(solvent)
The photosensitive coloring composition is mixed with a solvent such as water or an organic solvent in order to enable uniform coating on the substrate. When the composition of the present invention is a colored layer of a color filter, the solvent also has a function of uniformly dispersing the pigment. Examples of the solvent include cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, xylene, ethyl cellosolve, methyl-n amyl ketone, propylene glycol monomethyl ether, toluene, Examples include methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, petroleum solvent, and the like. These may be used alone or in combination. The solvent can be contained in an amount of 800 to 4000 parts by mass, preferably 1000 to 2500 parts by mass with respect to 100 parts by mass of the pigment in the coloring composition.

(Film thickness, liquid crystal layer thickness and liquid crystal drive electrode)
As described above, the technology according to the present invention is suitable for a vertical electric field type liquid crystal driving method such as VA and TN. In the method of applying a driving voltage of liquid crystal between the transparent electrode on the color filter and the pixel electrode of the array substrate on which the liquid crystal driving element (TFT), which is the opposite substrate, is formed, usually the liquid crystal thickness (cell gap) The thinner one can increase the response speed of the liquid crystal.

  In the main liquid crystal driving method described above, the liquid crystal thickness is in the range of about 2 μm to 4 μm. In addition, since the color (color change) when viewed from an oblique direction is smaller when the liquid crystal thickness is reduced, the liquid crystal thickness is from the viewpoint of improving responsiveness and coloring, and from the viewpoint of the amount of liquid crystal material used. Thinner is better. In addition, the film thickness of a colored pixel means the thickness from the surface of a colored pixel center to the transparent substrate surface which the said colored pixel touches.

  However, the thinner the liquid crystal is, or the larger the liquid crystal display screen is, the greater the influence of dust and foreign matter at the time of forming the liquid crystal cell. Therefore, the lower limit of the liquid crystal thickness in the vertical electric field method is about 3 μm. In order to reduce the thickness of the liquid crystal layer, the refractive index anisotropy Δn of the liquid crystal to be used is desirably larger than 0.07.

  Usually, in a liquid crystal display device, the alignment and response of liquid crystal are reduced by reducing the pitch of comb teeth (striped pattern) of a comb-like pixel electrode (usually a conductive metal oxide thin film called ITO) used as a pixel electrode. Property and transmittance can be improved. Note that the pitch of the comb teeth may be adjusted so as to be proportional to the wavelength of each main transmittance peak of the colored pixels.

  The transparent conductive film formed on or under the color filter may have an opening or a slit for controlling the liquid crystal alignment. The relative dielectric constant of the colored pixels constituting the color filter is approximately in the range of 3 to 4.5, depending on the type of organic pigment contained in the colored pixels and the pigment ratio. In Example 4 and Example 5, which will be described later, in which a transparent conductive film is disposed below the colored pixel, it is desirable to align the relative dielectric constant of the colored pixel.

  In the transflective liquid crystal display device, the optical path difference between the transmissive part and the reflective part (in the reflective part, incident light is reflected by a light reflective electrode described later and passes through the liquid crystal layer twice). The thickness of the liquid crystal layer is preferably about ½ of that of the transmission part.

  By forming the pixel electrode or the common electrode disposed on the array substrate with a light-reflective metal (aluminum alloy or silver alloy) thin film, a reflective liquid crystal display device can be obtained. Alternatively, the pixel electrode can be formed as an electrically independent reflective film using an aluminum alloy used for TFT wiring. A reflective film may be used as a storage capacitor (CS) between the pixel electrode and the reflective film via an insulating layer.

(Pedestal, spacer and orientation control structure)
The spacer pedestal used for the color filter substrate according to this embodiment may be formed only at least in a portion where a spacer to be described later is formed and a portion necessary for light shielding of an active element such as a TFT. Further, it is desirable that the spacer base is simultaneously formed of the same material as the light shielding layer that is the frame portion. Specifically, a photomask having a plurality of different patterns of transmittance, such as a gray tone (a gradation mask having a portion whose transmittance has been changed in at least three stages, such as black, gray, and white), or a pedestal The light-shielding layer is exposed to light using a photomask having an opening smaller than the pattern size (the exposure amount is adjusted by adjusting the size of the opening) or an opening with a specially designed opening shape, and then developed. And the pedestal can be formed simultaneously.

  As a photomask, a photomask having a light-shielding pattern as a thin film of metal chromium, a semi-transmissive portion as a metal oxide film such as ITO, and a transmissive portion without formation of these films may be used. The metal oxide film has an advantage that the transmittance can be adjusted by the film forming conditions and the film thickness.

  Further, the present inventors have confirmed that in a pedestal made of the same material as the frame portion (light-shielding layer) and a black matrix described later, reducing the thickness of the pedestal or black matrix is effective in improving flatness. . According to the detailed examination results of the present inventors, if the thickness of the pedestal is 1.0 μm or less, it is easy to stably obtain the thickness of the colored layer laminated thereon.

  FIG. 7 shows the relationship between the thickness of the pedestal and the thickness of the laminated portion of the colored layer on the pedestal. As shown in FIG. 7, when the thickness of the pedestal exceeds 1.2 μm, the thickness of the colored layer laminated thereon is thin and suddenly changes, and becomes unstable. Conversely, when the film thickness is as small as 0.3 μm or less, it is difficult to obtain a stable film thickness in the photolithography process. Therefore, the preferred thickness of the pedestal is 0.4 μm to 1.0 μm.

  The film thickness of the black matrix to be described later may be formed with a thin film thickness of 0.4 μm or less, and the formation of the black matrix may be omitted. FIG. 7 shows the film thickness of the laminated part when the thickness of the colored layer is 4.5 μm. In the range of 1.5 μm to 5 μm, which is a practical film thickness range of the colored layer. Show similar trends. In Example 4 or Example 5 described later in which a transparent conductive film is disposed below the colored pixel, the black matrix may be formed thicker than the above, or black using a conductive pigment such as carbon. A matrix may be formed.

  The pattern shape of the pedestal can be used in combination as a light shielding pattern for suppressing generation of a photocurrent due to light incident on an active element such as a TFT that drives liquid crystal. For the light shielding of active elements such as TFTs, it is sufficient that the optical density is 1, so the addition of the film thickness of the pedestal of 0.4 μm to 1.0 μm and the film thickness of the overlapping portion of the colored pixels is sufficient. Moreover, in the structure which concerns on this invention, since the several colored layer is laminated | stacked as a spacer on the base, light-shielding property can be added further.

  The color of the colored layer forming the spacer can be appropriately selected according to the purpose and specifications. For example, if priority is given to the light shielding property to an active element such as a TFT, it can be selected so as to include a red colored layer having a light shielding property for short-wavelength light. If the rounded shape is prioritized, a blue colored layer that has less pigment content than the other two colors and has fluidity can be selected as the top layer of a three-layer stack or a two-layer stack spacer. it can.

  The color filter according to the present embodiment may be a color filter of four or more colors provided with a color pixel of complementary color such as a yellow pixel or a white (transparent) pixel in addition to a blue pixel, a red pixel, and a green pixel. In addition to a spacer (main spacer) having a height corresponding to the thickness of the liquid crystal, a sub-spacer having a low height may be provided. When the main spacer is a three-layer stack, for example, a two-layer stack sub-spacer may be provided only in the frame portion. The main spacer and the sub-spacer may each be a single colored layer or may be formed of a transparent resin. The sub-spacer can be a low-height spacer by using a photomask having openings with different transmittances, such as a gray-tone mask, or using a photomask having small-diameter openings.

  Alternatively, a spacer or a liquid crystal alignment control structure may be formed on the transparent conductive film. When both the spacer and the alignment control structure are formed, they may be simultaneously formed of the same material using a colored resin or a transparent resin, as described above.

  The technology according to the present invention can be applied to a liquid crystal display device having a thin liquid crystal layer in the near future. However, in a thin liquid crystal layer having poor liquidity of the liquid crystal, for example, an arrangement of spacer formation near the liquid crystal sealing port is used. The number of spacers and the layout may be adjusted in consideration of the flow of the liquid crystal material at the time of forming the liquid crystal cell, such as by changing. In the color filter substrate according to the present embodiment, the light shielding layer and the pedestal can be formed in the same photolithography process, as will be described later.

  In the color filter substrate according to the present embodiment, the spacer is formed in units of colored pixels, for example, in the central longitudinal direction of the pixel (the center of the pixel or one central part of the long side of the pixel, or one central part of each of the transmission part and the reflection part). In addition, it can be formed as a structure that also functions as a liquid crystal alignment control function. A circular shape, a rhombus shape, a polygonal shape, a cross shape, or the like can be adopted as the planar view shape of the structure. The TFT element for driving the liquid crystal can also be formed in the central longitudinal direction of the pixel in accordance with the spacer position as the liquid crystal alignment control structure. For example, when the liquid crystal alignment control structure has a rhombic shape in plan view, the pixel electrode on the TFT substrate side has a rhombic concentric slit shape (a slit shape in which transparent electrode openings and patterns are alternately arranged in a V shape). May be disposed so as to surround the spacer.

  By using the photo-alignment method, the alignment control structure having a function of distinguishing the alignment of the liquid crystal can be formed in the shape as described above. For example, by applying multiple types of alignment film mixed materials such as a photo alignment material with a horizontal alignment function and a photo alignment material with a vertical alignment function to form an alignment film, and then irradiating ultraviolet diffused light from the center of the pixel The direction and gradient of the liquid crystal tilt from the center of the pixel can be given in a plan view and a point-symmetric (or line-symmetric) direction. As an example in which one pixel has a line-symmetric liquid crystal alignment, for example, with the above alignment control structure as a starting point, the pixels on the array substrate side are divided into left and right, different alignment directions, and different alignments on the upper and lower sides on the color filter substrate side Can be direction.

  The ultraviolet rays used for liquid crystal alignment may be non-polarized light, but polarized ultraviolet rays are preferable from the viewpoint of control. In the configuration in which the alignment film on the array substrate side gives the gradient of the liquid crystal tilt point-symmetric within one pixel, the alignment is performed at the center of the pixel formed on the color filter substrate (or the center of the transmission part and the reflection part, respectively). Preferably, a control structure is formed. Suitable for a wide viewing angle by giving the alignment film of the array substrate a point-symmetrical / line-symmetric alignment direction and giving a uniform alignment in the vertical direction to the alignment film of the liquid crystal formed on the color filter, for example. Liquid crystal domains can be formed. If light alignment that is balanced with the transmissive part is difficult due to the light-reflective electrode (reflective electrode) or reflective film formed on the array substrate, an alignment gradient for the liquid crystal is formed on the color filter substrate side, and the array The substrate side may be uniformly oriented.

  Prior to the formation of the photo-alignment film, an ultraviolet absorption layer may be formed on the color filter in advance. The UV absorbing layer is laminated on the color filter as a coating film containing UV absorbers such as coumarin, benzophenone, benzotriazole, benzoxazinone and the like in a transparent resin in a solid ratio of about 0.5 to 10% by weight. It ’s fine. A thin transparent resin layer may be further laminated on the ultraviolet absorbing layer.

  The structure combining the spacer and the alignment control structure proposed by the present inventors can substantially increase the aperture ratio of the liquid crystal display device and improve the brightness. In general, the alignment control structure can be formed with a high height or with a high density to improve the response of the liquid crystal. However, these techniques substantially reduce the aperture ratio of the pixel. . In the proposed technique of the present invention, since the spacer and the alignment control structure can be used together, the aperture ratio is not lowered.

  The spacer used for the color filter substrate according to the present embodiment can be formed with a smooth cross-sectional shape by covering the entire spacer with a blue colored layer as the uppermost layer, which is rich in fluidity when the spacer is thermally cured.

  It is also possible to form the spacer in a single color (for example, a red colored layer). Forming the spacer in a single color has the following advantages. That is, the technique of forming two or three colored layers and independently forming a spacer is more advantageous in terms of liquid crystal alignment than the technique (Patent Document 1) that uses simple color superposition as a spacer. However, in order to absorb the positional deviation when the colors are superimposed twice and three times, it is necessary to form a large bottom area of the colored layered portion of the first color, which adversely affects the pixel aperture ratio. In addition, when an independent thin and tall spacer is formed by stacking colored layers, the first color, the second color, and the third color are stacked with a thin film thickness separated from the film thickness of the colored pixels. There are difficulties in checking the conditions in the height design and manufacturing process. The technique of forming the spacers by independently arranging the two or three layers of the colored layers has been problematic because the above-described confirmation work is required for each type of color resist to be used and each type of color filter to be manufactured. Forming the spacers in a single color can solve these problems.

Instead of the spacer made of the colored layer, the spacer can be formed with a transparent resin or a colored resin after forming the transparent conductive film or after forming the liquid crystal alignment film. The surface of the spacer formed after the transparent conductive film can be subjected to necessary surface treatment such as imparting hydrophilicity so as not to hinder the liquid crystal alignment on the array substrate side. The spacer or the alignment control structure is preferably a low dielectric constant material.
(Black matrix thickness)
FIG. 8 shows a light-shielding layer 2, a pedestal 4, a black matrix 8, a red pixel 3R, a green pixel 3G, a spacer 5 formed by stacking colored layers, and a low height in a color filter substrate according to still another embodiment of the present invention. FIG. 3 is a diagram showing a planar view arrangement of sub-spacers 6 and cell gap adjustment layers 15. That is, in FIG. 8, a black matrix 8 is provided that separates three colored pixels including a red pixel 3R, a green pixel 3G, and a blue pixel 3B. FIG. 2 shows a cross section taken along the line CC ′ of FIG.

  One of the features of one embodiment of the present invention is that the light shielding layer, the cell gap regulation layer laminated on the light shielding layer, the total film thickness, and the green pixel thickness are substantially the same, and the flatness suitable for the alignment of the liquid crystal is obtained. It is an object of the present invention to provide a color filter substrate having no leakage of light at the frame portion due to poor liquid crystal alignment. The present inventors have confirmed that the film thickness of the black matrix made of the same material as that of the frame portion (light shielding layer) affects the improvement of flatness. Note that the black matrix is a lattice-shaped light shielding pattern that is usually formed so as to surround the colored pixels for the purpose of improving contrast, but may be formed in a stripe shape in the longitudinal direction of the pixel. Further, in the present invention, a color filter substrate without a black matrix may be used. Alternatively, the black matrix, the pedestal, and the light shielding layers having different thicknesses may be formed in two steps using different photomasks. Alternatively, a black matrix, a pedestal, and a light shielding layer having different film thicknesses may be formed by adjusting the number of shots in laser irradiation exposure.

  FIG. 9 shows the relationship between the film thickness of the black matrix and the height above the protrusions of the end portions of the colored pixels that are superimposed on the black matrix 8. If the film thickness of the black matrix 8 exceeds 1.1 μm, the height of the protrusion 7 becomes extremely high, which is not preferable for liquid crystal alignment. When the thickness of the black matrix is less than 1 μm, and further less than 0.8 μm, the projection height at the end of the colored pixel is 0.25 μm, and further lower than 0.2 μm.

  A color filter that can ensure good flatness, including variations in the thickness of the colored pixels, less than ± 0.15 μm, and meets the high demands of high-quality liquid crystal display devices such as the VA method and the HAN method. Can be provided. Moreover, it becomes a color filter having high flatness within a 1/4 wavelength range (± 0.15 μm) of green wavelength 550 nm, which has high visibility to human eyes, and can reduce coloring unevenness. However, in the configuration in which the planarizing layer is laminated with a transparent resin on the color filter, the film thickness of the black matrix or the pedestal may be greater than 1 μm. The thickness of the planarizing layer is generally in the range of 1 μm to 3 μm.

  Similar to the pedestal, the black matrix can be formed simultaneously with the light shielding layer by a photolithography technique using a gray tone mask, a half tone mask, or the like. Alternatively, the exposure amount of the light-shielding layer and the black matrix may be formed by changing the number of shots with a difference in film thickness by using laser exposure.

  Although FIG. 9 does not show a black matrix having a thickness of less than 0.4 μm, the present inventors have confirmed that the height of the protrusions superimposed on the thin black matrix is low. Yes. Unlike the light-shielding layer (frame portion), the black matrix is not required to have a light-shielding property. Therefore, in the present invention, the formation of the black matrix may be omitted, and the black matrix may be substituted only by overlapping the colored layers of different colors. Note that light from a light source (backlight) disposed on the back surface of the transmissive liquid crystal display device can be shielded by a scanning line or a signal line of an active element such as a TFT.

  The height of the spacer 5 in the effective display area is substantially the same as that of the effective display area, but the adjustment of the height is performed by processes such as selection of the pedestal thickness and the colored layer, application in the color filter manufacturing process, development, and hardening. Various adjustments can be made according to the spacer diameter (size). The pedestal 4 ′ not formed with the spacer 5 is disposed for the purpose of adjusting the aperture ratio of the red pixel R, the green pixel G, and the blue pixel B and shielding the active elements such as TFTs.

  Further, in the configuration in which the transparent conductive film is formed on the black matrix shown in Example 5 described later, the black matrix can be formed to a thickness of 1 μm or more in order to form an effective oblique electric field.

(Cell gap adjustment layer)
FIG. 2 shows an example in which the cell gap adjusting layer 15 according to the present invention is partially disposed on the colored pixels. In this example, the cell gap adjustment layer 15 is stacked on the reflective portion of the colored pixel 3G and the upper part of the retardation layer 11 at the same position as the planar view reflective portion 25. As described above, the cell gap adjustment layer 15 is provided for the purpose of adjusting the optical path difference between the transmission part and the reflection part. Therefore, a resin material having at least high visible light permeability and heat resistance necessary for the liquid crystal panel process can be used for the cell gap adjustment layer. As shown in FIG. 3, the cell gap adjustment layer 15 ′ is also disposed on the frame-shaped light shielding layer 2, and the total thickness of the cell gap adjustment layer 15 ′ and the light shielding layer 2 is equal to the film thickness of the green pixel. It is almost equal.

  The cell gap adjustment layer 15 is mainly intended to adjust the optical path difference between the liquid crystal transmission part and the reflection part as a liquid crystal display device. For example, the cell gap adjustment layer 15 uses a photosensitive alkali-soluble resin and a part such as a gray tone mask. Alternatively, the thickness may be changed using photomasks having different transmittances. You may change thickness according to the wavelength of the light of the main transmission part of a coloring pixel. The cell gap adjusting layer may be formed with a thin film thickness in the transmissive portion, in addition to being formed thick in the reflective portion.

  The cell gap adjusting layer 15 can be formed of the above-described transparent resin, alkali-soluble resin, or acrylic resin. Since the cell gap adjusting layer 15 is formed in a pattern, it is preferable to use an alkali-soluble resin that can be patterned by a photolithography process as the material. Even if a thermosetting resin is used, the pattern can be formed by dry etching or lift-off techniques. In addition, as in the embodiment shown in FIG. 1, it is more preferable that the cell gap adjusting layer is constituted by the light scattering layer 12.

  As described above, the color filter substrate according to the present invention is particularly applied to a transflective liquid crystal display device. The colored pixel of the color filter of the present invention is divided into a transmissive part and a reflective part, and a light scattering layer 12 is arranged in the reflective part of the colored pixel as shown in FIG. That is, the light scattering layer 12 is disposed at the same position in plan view on the retardation layer 11 formed in the concave portion of the reflective portion of the colored pixel.

  The light scattering layer 12 is formed by dispersing single or plural kinds of amorphous fine particles in a matrix resin 14 having different refractive indexes, and has a paper white-like effect on the eyes of an observer by scattering incident light. It is an optical functional film. The matrix resin 14 may be a transparent resin that is heat resistant and transparent in the visible range. The film thickness of the light scattering layer 12 is preferably in the range of about 1.5 μm to 5 μm because of the relationship between the amorphous fine particle diameter, the wavelength of light, and the suitability in the manufacturing process.

Examples of the amorphous fine particles 13 of the light scattering layer 12 include fine particles made of an inorganic material and fine particles made of an organic polymer. In particular, organic polymer fine particles are mainly listed because they are amorphous, but even inorganic fine particles are not problematic as long as they are amorphous. A method of expressing amorphous fine particles in the matrix resin by phase separation described later may be used. Amorphous fine particles may be formed by a photolithography technique, and a matrix resin (hereinafter referred to as a transparent resin) may be applied thereon.
For example, inorganic fine particles include spherical amorphous fine particles such as silica and alumina oxide, and organic polymer fine particles include acrylic fine particles, styrene acrylic fine particles and their cross-linked products, melamine fine particles, melamine-formalin condensate, Fluoropolymers such as tetrafluoroethylene), PFA (perfluoroalkoxy resin), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), PVDF (polyfluorovinylidene), ETFE (ethylene-tetrafluoroethylene copolymer), Examples include silicon resin fine particles. Among them, crosslinked acrylic resin fine particles have a refractive index of less than 1.5, and silica particles or silicon resin fine particles have a refractive index of 1.42 to 1.45 (halogen lamp D). Line 589nm) Preferred.

  Moreover, these fine particles should just be mainly contained as the fine particle in a light-scattering layer, for example, should just contain about 70% or more of fine particles. In addition to these fine particles, non-spherical fine particles such as irregular fine particles and small amounts of crystalline fine particles of about 30% or less are used for the purpose of finely adjusting the dispersion stability of the fine particles in the coating liquid and light scattering characteristics. May be added.

Furthermore, these fine particles can be applied as the fine particles after appropriate surface treatment is performed to improve the solvent dispersibility and compatibility with the transparent resin. Examples of such a surface treatment include, for example, a treatment of applying and coating SiO ₂ , ZrO ₂ , Al ₂ O ₃ , ZnO, a transparent resin, a coupling agent, or a surfactant. In addition, other examples include a treatment that causes a surface reaction with alcohol, amine, organic acid, or the like.

  The shape of the amorphous fine particles 13 is not particularly limited, but is a spherical shape or a shape similar to a spherical shape. The spherical fine particles can be easily controlled in size, particle size distribution, and the like, and therefore, the optical characteristics of the light scattering layer 12 can be easily controlled. The particle size of the fine particles is not particularly limited, and the allowable range varies depending on the film thickness of the target light scattering layer and the presence or absence of coloring. However, it is usually not preferable to use fine particles larger than the thickness of the light scattering layer because the surface of the light scattering layer becomes very rough. The particle size of the fine particles is not particularly limited, but a preferable particle size range is an average particle size of about 0.8 μm to 3 μm, preferably an average particle size of 1 μm to 2 μm.

  The specific gravity of the fine particles does not directly affect the optical characteristics of the light scattering layer, but has a great influence on the coating characteristics when the light scattering layer 12 is formed, and is also related to the characteristics of the light scattering layer 12 itself. . Therefore, it is desirable for the stability of the coating liquid that the value is close to the specific gravity of the solution of the matrix resin 14.

  The matrix resin 14 in which the fine particles are dispersed preferably has a high visible light transmittance and has sufficient resistance to heat treatment and chemical treatment during the manufacturing process of the liquid crystal display device. Epoxy-modified acrylic resins, fluorene resins, and polyimide resins can be used. As resins having a low refractive index, fluorine-modified acrylic resins and silicon-modified acrylic resins can be used. In addition, acrylic resin, epoxy resin, polyester resin, urethane resin, silicon resin, and the like can be used as appropriate.

  When the light scattering film layer is provided in a pattern by a photolithography process, an acrylic resin or an epoxy resin having photosensitivity and developability can be used. Also, these resins can be used in combination with heat curing or ultraviolet curing.

  For example, when the fine particle is a crosslinked acrylic fine particle having a refractive index of 1.49 (value using a halogen lamp D line of 589 nm), the refractive index of the matrix resin is preferably 1.55 to 1.65. Further, when the fine particles are silica particles or silicon resin fine particles having a refractive index of 1.42 to 1.45, the matrix resin preferably has a refractive index of 1.50 to 1.60.

  The light scattering layer 12 is formed in an arbitrary shape through a photolithography process after the amorphous fine particles 13 are mixed and dispersed in a transparent resin 14 which is a matrix resin, coated on a transparent substrate, dried. As a coating method, spin coating, flow coating, roll coating, or the like can be applied, and as an exposure method, projection exposure or proximity exposure can be applied.

  Examples of the amorphous fine particles 13 in the light scattering layer 12 include fine particles that can be formed by mixing two resins and performing phase separation. Amorphous fine particles 13 can be formed by selecting an appropriate amount of two or more resins and additives having different refractive indexes and applying and drying a coating solution dissolved in a solvent on the substrate.

  Phase separation grows when the two resins are mixed in the solution, or when the solvent is volatilized by coating and drying on the substrate, and when the coating film is dried, transparent amorphous fine particles 13 are formed. it can. At this time, one phase-separated resin tries to grow into a spherical shape in the solution, but when coated on the substrate, the film volume decreases as the solvent in the coating film volatilizes, and the spherical shape grows. The volume increases, but grows while deforming from a spherical shape to a disk shape due to the stress from the upper surface.

One resin is generated and grown as droplets from two resin solutions, and the amorphous fine particles 13 are formed under the condition that one resin is A and the other resin is B. 1) The amount of A is more than the amount of B Less,
2) The surface tension of the A solution is larger than the surface tension of the B solution,
3) The evaporation rate of solution A is greater than the evaporation rate of solution B;
4) The molecular weight of A is larger than the molecular weight of B, and the magnitude of the amount is a constraint on strength.

  When the amorphous fine particles are generated and formed by phase separation from two or more types of resin solutions having different refractive indexes, the amorphous fine particles stay inside the film and do not come out on the surface. The surface of the layer becomes flat, and the film thickness of the color filter becomes uniform.

  The transparent matrix resin 14 and the amorphous fine particles 13 formed by phase separation desirably have high visible light transmittance and sufficient resistance to heat treatment and chemical treatment during the manufacturing process of the liquid crystal display device.

  For example, an epoxy-modified acrylic resin, a fluorene resin, a polyimide resin, and a melamine resin can be applied as a resin having a high refractive index, and a fluorine-modified acrylic resin and a silicon-modified acrylic resin can be applied as a resin having a low refractive index. In addition, acrylic resin, epoxy resin, polyester resin, urethane resin, silicon resin, and the like can be used as appropriate.

  Amorphous fine particles are easily available in a spherical shape, and the refractive index of transparent silica and silicon resin is 1.43 to 1.44, and the refractive index of crosslinked acrylic resin is 1.49. Applicable as high resin.

  When the light scattering layer is provided in a pattern by a photolithography process, an acrylic resin or an epoxy resin having photosensitivity and developability can be used. It is also possible to use a thermosetting resin or an ultraviolet curable resin.

  In addition to the above resin, a surfactant for improving coating suitability, a photopolymerization initiator for imparting photosensitivity, a sensitizer, and the like can be added.

  Examples of the amorphous fine particles 13 in the light scattering layer 12 include shapes different from the above two examples and different manufacturing processes. That is, a transparent resin is applied and dried on a substrate, and a number of fine reliefs having a film thickness of several μm and a pattern size of several μm to several tens of μm are formed using means such as a photolithography method, and the relief is softened by heating. Thereafter, thermal crosslinking is performed. A light scattering film layer can be formed by applying a transparent resin having a different refractive index thereon.

  If the amorphous fine particles are hemispherical microlenses formed by melting a fine resin pattern, the light scattering characteristics can be adjusted by changing the pattern shape (size, shape, density). Alternatively, a directional light scattering layer can be obtained by making the cross-sectional shape of the microlens asymmetrical or parabolic.

  The size of the pattern of the light scattering layer that is the cell gap adjusting layer is preferably the same as the size of the retardation layer in plan view or larger than that of the retardation layer.

  In the liquid crystal display device configured using the color filter substrate according to this embodiment, when the cell gap adjustment layer is formed on the array substrate facing the color filter substrate, the cell gap adjustment layer on the color filter substrate is formed. It can be omitted. Alternatively, a color filter substrate applied to a transflective liquid crystal display device (for example, a technique disclosed in Japanese Patent Laid-Open No. 2003-29252 or Japanese Patent Laid-Open No. 2009-93115) in which the liquid crystal layers of the transmissive portion and the reflective portion are close in thickness. Thus, the cell gap adjusting layer can be made thinner or omitted.

(Colored pixel overlap shape)
As an exposure apparatus for TFT, an apparatus with high alignment accuracy in which 3σ is 1.5 μm is commercially available. In the case of TFT, an alignment mark attached to the metal wiring is used. However, in the case of a color filter, it is attached to an organic film (for example, a photosensitive colored composition film such as a black matrix). Use alignment marks. Similarly, in the colored layer to be laminated, the alignment mark is attached to the organic film, the film thickness of the organic film is 1 μm to 4 μm, which is thicker than the TFT wiring, and the pattern edge is also tapered. The alignment accuracy must be at least 3 μm and 4.5 μm alignment accuracy.

  As described above, the liquid crystal thickness of the VA or TN liquid crystal display device is about 2 μm to 4 μm. The thickness of the colored layer in the color filter of the present invention is about 0.6 to 1 times the liquid crystal thickness. Therefore, the specific thickness of the colored layer is about 1.2 μm to 4 μm.

  The line width of the black matrix is about 5 μm to 30 μm, although it differs for mobile (small) liquid crystal display devices and large TVs. When giving priority to the aperture ratio of the pixel, as described above, the formation of the black matrix may be omitted.

FIG. 10 shows the pattern edge shape of the thick colored pixel 22 and FIG. 11 shows the pattern edge shape of the thin colored pixel 23. The length m and n of the pattern edge related to the alignment is 4.5 μm, and the thickness of the colored layer 22 and the thickness t of the colored pixel 23 are 1.2 μm to 4.0 μm. When the taper angles θ ₁ and θ _{2 of} the pattern edges (angles formed with the surface of the transparent substrate 1 at the end of the colored pixels) are calculated, the angle range is about 15 ° to 40 °. Therefore, although depending on the film thicknesses s and t of the colored layers 22 and 23, in order to obtain good flatness, it is desirable to form the end shape of the colored pixel at a taper angle of 15 ° to 40 °. .

  The end shape of the colored pixel can be controlled by various methods such as changing the amount of the polymerization initiator, the developing method, and the exposure amount. The planar view shape of the colored pixels is preferably a continuous stripe shape of the colored pixels.

  On the color filter substrate according to the present embodiment, a fine texture of the color filter surface, a cell gap adjustment layer surface described later, a surface of 0.1 μm or less such as a process (orientation process) before the cell gap adjustment layer is formed. A protective layer or an insulating layer made of a transparent resin may be laminated for the purpose of covering unevenness and improving the electrical insulation. The protective layer can be formed so as to ensure followability (opposite to ensure flatness) by increasing the molecular weight of the transparent resin to be used in order to ensure the height of the spacer to some extent. . The spacer height can be secured by coating and forming the protective layer with a thin film thickness of, for example, 0.05 μm to 0.3 μm. Alternatively, a protective layer having a thickness of 1 μm or more may be formed of a transparent resin or the like by previously forming a high spacer. The protective layer may also serve as an alignment film, or may be applied and formed in advance before the pretreatment of the retardation layer described later. Or you may contain the additive (for example, ultraviolet absorber) which assists the photo-alignment of the phase difference layer or the alignment film of a liquid crystal. Further, a transparent conductive film made of a metal oxide thin film called ITO or the like may be formed through a protective layer. Further, a protrusion may be formed in the pixel in advance using the same material as the light shielding layer, and a colored layer may be further stacked to be used as an alignment control structure. A spacer and an alignment control structure may be used together. For example, a TFT element for driving a liquid crystal on the TFT substrate side and a pedestal on the color filter substrate side are formed at the center of the pixel so as to face each other, so that it can be used as a spacer for a vertically aligned liquid crystal display and an alignment control structure. it can.

  The transparent conductive film may be formed in a comb-like shape, and slits that are openings may be formed in the transparent conductive film for the purpose of controlling liquid crystal alignment and preventing liquid crystal disclination. Alternatively, formation of a pattern necessary for imparting an oblique electric field effect in the technology disclosed in HAN and Patent Document 8 can be performed on the transparent conductive film.

(Retardation layer)
The reflection part of the transflective liquid crystal display device has a difference in phase difference caused by liquid crystal in addition to the optical path difference as compared with the transmission part. Due to such a difference in phase difference between the reflective part and the transmissive part, the reflected light and black display of the reflective part may be colored, or the display that should be normally black display may be normally white display, The problem of phase difference is significant.

  On the other hand, this problem can be solved by shifting the phase difference of the 1/4 wavelength of incident light and adding a phase difference of 1/4 wavelength by reflection at the reflection electrode (incident converted to linearly polarized light). The light is rotated by 90 degrees in one reciprocation in the thickness direction of the retardation layer).

  In the transflective liquid crystal display device according to the present invention, a polymer liquid crystal or a crosslinkable polymer liquid crystal is used as a specific method for imparting a function of changing a quarter wavelength phase or a half wavelength phase to the retardation layer. Examples thereof include a coating formation method using a solution, a method of adding a birefringence modifier to the alkali-soluble transparent resin described above, a method of using a polymerizable liquid crystal compound, and the like. In the case of a polymerizable liquid crystal compound, a discotic polymerizable liquid crystal compound or a rod-shaped polymerizable liquid crystal compound having a disc-like molecular structure can be used. You may form combining these methods and materials which were listed.

  Further, in order to enhance the reproducibility of imparting the function of changing the polarization phase by a quarter wavelength phase or a half wavelength phase, an orientation film may be formed or an orientation treatment may be performed before the retardation layer is formed. When the alignment can be adjusted by the amount of exposure and the exposure wavelength as in the case of the polymerizable liquid crystal compound, the density and the alignment direction of the alignment can be adjusted by the color of the colored pixel. For the alignment treatment of the alignment film, the same optical alignment treatment as that for the polymerizable liquid crystal compound can be employed.

  As the exposure machine, an ultrahigh pressure mercury lamp, a YAG laser, a solid-state laser, a semiconductor laser, and the like can be appropriately selected including the exposure wavelength. Like laser exposure, the alignment density and alignment direction can be adjusted by selecting the exposure wavelength, adjusting the exposure amount by the number of laser shots, the incident angle of the laser beam, and the like. Selective exposure may be performed for each corresponding colored pixel using a plurality of photomasks. Irradiation from a plurality of directions may be performed at a time. The exposure may be performed with polarized light irradiation or non-polarized light irradiation. Immobilization may be performed by non-polarization irradiation while heating after polarization irradiation first. When there is oxygen inhibition, it is preferably performed in an inert gas atmosphere.

  The thickness of the retardation layer may be adjusted in the range of about 0.5 μm to 5 μm according to the color filter constituent material alone or the birefringence of the liquid crystal applied to the liquid crystal display device. The difference in retardation of the retardation layer can be adjusted by the addition amount, type, and blend of the polymerizable initiator added to the polymerizable liquid crystal compound in addition to the exposure amount. Further, when the polymerizable liquid crystal compound is a monomer, the crosslinking density can be increased by using a plurality of monomer reactive groups, and a highly reliable retardation layer can be obtained.

  The retardation layer may be a retardation layer that matches the wavelength of each principal transmitted light of the colored pixel. In the case of normally black display, not only a retardation layer formed on a colored pixel but also a retardation layer on a light shielding layer (frame portion) is provided with a function of changing the phase of a quarter wavelength or a half wavelength. Thus, light leakage can be eliminated. Furthermore, a quarter wavelength layer and a half wavelength layer may be overlapped to form a broadband retardation layer. In the normally black liquid crystal display device, the retardation layer 11 ′ is placed on the frame-shaped light shielding layer 2 so that the total thickness of the retardation layer 11 ′ and the light shielding layer 11 is substantially equal to the thickness of the green pixel. By forming the film, light leakage can be eliminated and image quality can be improved.

  When a polymerizable liquid crystal compound is used as the retardation layer, an alignment film may be applied and formed as a pretreatment before the retardation layer is formed, and the alignment treatment may be performed. In addition, it is desirable to form an alignment film for liquid crystal alignment after forming a retardation layer to form a color filter substrate. When this alignment film is an alignment film whose alignment amount can be adjusted with an energy beam such as ultraviolet rays, the alignment amount of the transmission part and the reflection part is changed by laser exposure as described above, or the alignment for each color is made different. be able to. Alternatively, the alignment film used for the alignment treatment of the retardation layer can be used for liquid crystal alignment of the transmission part, and a film having a different alignment function can be separately formed on the retardation layer of the reflection part.

  Examples of organic compounds that can be used for the alignment film serving as the base of the retardation layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleimide copolymer, polyvinyl alcohol, and poly (N-methylolacrylamide). , Styrene / vinyl toluene copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, polyamide, polyvinyl alcohol, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer And polymers such as carboxymethylcellulose, polyethylene, polypropylene and polycarbonate, and compounds such as silane coupling agents. Examples of preferable polymers include polyimide, polystyrene, polymers of styrene derivatives, gelatin, polyvinyl alcohol, and alkyl-modified polyvinyl alcohol having an alkyl group (preferably having 6 or more carbon atoms).

  An orientation effect can also be obtained by rubbing the colored pixel surface of the color filter. Furthermore, commercially available alignment film materials can be applied, for example, an alignment film material (Sunever) manufactured by Nissan Chemical Co., Ltd., an alignment film material (QL, LX series) manufactured by Hitachi Chemical DuPont Microsystems, Inc., an alignment film material manufactured by JSR ( AL series) and an orientation agent (Rixon aligner) manufactured by Chisso Corporation. These alignment film materials can be added by adding an organic solvent such as gamma-butyrolactone, diethylene glycol monoethyl acetate, diethylene glycol monobutyl acetate, or cyclohexanone when the viscosity is adjusted as an inkjet ink.

  For the alignment treatment of the alignment film serving as the base of the retardation layer, the same method as the alignment method of the liquid crystal alignment film used as the liquid crystal display device can be employed. For example, in addition to a rubbing method that mechanically rubs the surface of the alignment film, a photo-alignment method using ultraviolet light may be used. The ultraviolet light source can be appropriately selected such as the wavelength, irradiation angle, and irradiation amount of the ultraviolet light to be exposed, such as an ultrahigh pressure mercury lamp, a low pressure mercury lamp, a short arc type xenon lamp, a solid laser, a YAG laser, and a semiconductor laser. The ultraviolet light may be irradiated from a plurality of directions such as two directions and four directions.

  In the embodiments of the present invention to be described later, an example of the simplest inkjet method for forming an alignment film pattern will be described. However, pattern formation is performed by a photolithography technique using a photosensitive alignment film material that can be developed. You can go.

  It is desirable to stack the cell gap adjusting layer or the retardation layer on the light shielding part to reduce the light shielding part step. As shown in FIG. 14, the reason is that the liquid crystal alignment unevenness due to the level difference “a” that has conventionally occurred in the colored pixels 3 and the light shielding layer 2 of the color filter is improved by improving the flatness of the color filter.

  In addition, the area ratio of the transmission part and the reflection part of the color filter substrate according to the present invention can be adjusted according to the purpose and conditions of use of the liquid crystal display device.

(Preparation of light shielding layer material / black composition)
(Pigment dispersion RD1)
As a coloring agent, C.I. I. Pigment red 254 / C.I. I. Pigment Red 177 = 80/20 (weight ratio) 20 parts of a mixture, 5 parts of BYK-2001 as a dispersant (in terms of solid content), and 75 parts of propylene glycol monomethyl ether acetate as a solvent are treated with a bead mill to obtain a pigment dispersion (RD1) was prepared.

(Pigment dispersion YD1)
As a coloring agent, C.I. I. A pigment dispersion (YD1) was prepared by treating 20 parts of Pigment Yellow 150, 5 parts of Solsperse 24000 as a dispersant (in terms of solid content) and 75 parts of propylene glycol monomethyl ether acetate as a solvent with a bead mill.

(Pigment dispersion BD1)
As a coloring agent, C.I. I. Pigment Blue 15: 6, 20 parts of Ajisper PB-821 as a dispersant (in terms of solid content), and 75 parts of propylene glycol monomethyl ether acetate as a solvent are treated with a bead mill to prepare a pigment dispersion (BD1) did.

(Pigment dispersion liquid VD1)
As a coloring agent, C.I. I. A pigment dispersion (VD1) was prepared by treating 20 parts of Pigment Violet 23, 5 parts of Ajisper PB-821 as a dispersant (in terms of solid content) and 75 parts of propylene glycol monomethyl ether acetate as a solvent using a bead mill.

(Synthesis of resin solution (P1))
The reaction vessel was charged with 800 parts of cyclohexanone, heated while injecting nitrogen gas into the vessel, and a mixture of the following monomer and thermal polymerization initiator was added dropwise to carry out a polymerization reaction.

Styrene 60 parts Methacrylic acid 60 parts Methyl methacrylate 65 parts Butyl methacrylate 65 parts Thermal polymerization initiator 10 parts Chain transfer agent 3 parts After dripping and heated sufficiently, 2.0 parts of thermal polymerization initiator was dissolved in 50 parts of cyclohexanone. Then, the reaction was continued and an acrylic resin solution was obtained. An acrylic resin solution was prepared by adding cyclohexanone to the resin solution so that the non-volatile content was 20% by weight, and it was designated as resin solution (P1). The weight average molecular weight of the acrylic resin was about 10,000.

(Black composition)
A mixture having the following composition was stirred and mixed so as to be uniform, and then filtered through a 5 μm filter to obtain a black composition. The black composition is used to form a light shielding layer and a pedestal in a later example.

21 parts of the above pigment dispersion (RD1) 17 parts of the above pigment dispersion (BD1) 4 parts of the above pigment dispersion (YD1) 9 parts of the resin solution (P-1) 4.8 parts of trimethylolpropane triacrylate Photopolymerization initiator ( "Irgacure-369" manufactured by Ciba Geigy Co., Ltd.) 2.8 parts Photosensitizer ("EAB-F" manufactured by Hodogaya Chemical Co., Ltd.) 0.2 parts Cyclohexanone 36.2 parts The black composition obtained as described above was coated After the formation, the cured film thickness is 1 μm, and the optical density (OD value) is approximately 1.8. The film thickness can be adjusted depending on the application conditions. It is also possible to adjust the optical density of the coating film by adjusting the component ratio of the resin solid ratio (resin solution). In addition, in the said black composition, since the green organic pigment has bad light-shielding property, it is not added.

(Measurement of optical density (OD))
The optical density (OD value) is a value representing the extent to which a substance absorbs light. When the optical path length is constant, the larger the OD value, the higher the concentration of the substance. The optical density (OD value) in the present invention is represented by the following mathematical formula (1). The tristimulus value Y with a C light source was measured using the Olympus spectroscope OSP-200 on the black composition coated substrate obtained above, and the optical density (OD) was calculated using Equation 1.

[Formula 1]
Optical density (OD) = − log (Y / 100) (1)
(Y is the tristimulus value Y with the C light source)
As a measurement sample, a black composition Blk diluted with an organic solvent and adjusted in concentration was applied on a glass substrate to a thickness of 1 μm and dried naturally. The mixture was heated on a hot plate at 90 ° C. for 1 minute to remove excess solvent and dry. Then, it baked in 230 degreeC oven for 1 hour, and was set as the optical density measurement sample of a light shielding layer. The optical density (OD) was approximately 1.8.

  The film thickness can be adjusted depending on the coating conditions. It is also possible to control the concentration by adjusting the component (solid content) ratio of the resin solution. When the film thickness is increased from 4 to 5 μm with the above black composition, it is possible to increase the blending amount of the resin solution and the solvent (cyclohexanone, etc.) and to set the organic pigment concentration to around 10% of the black composition. can do. The light shielding property at this time can be set in the range of 3 to 4 in terms of optical density.

  In the examples described later, the resin solid ratio and the solvent amount of the black composition were adjusted so that the optical density was about 3 at a film thickness of 1.6 μm.

(Preparation of resin composition for light scattering layer)
A photosensitive resin composition for a light scattering layer was prepared with the following composition.

Alkali-soluble photosensitive transparent resin A2
: Epoxy acrylate resin having a fluorene skeleton 4.5 parts by weight Transparent particles B3: MX180 (manufactured by Soken Chemical Co., Ltd.) 2 parts by weight Photopolymerization initiator C: Irgacure 819
(Ciba Specialty Chemicals Co., Ltd.) 0.45 parts by weight Solvent D: Cyclohexanone 21 parts by weight Photopolymerization monomer E: M400 (manufactured by Toagosei Co., Ltd.) 2 parts by weight A2, C and E are mixed, applied and dried. The refractive index of the transparent resin after exposure (200 mJ / cm ² ), development, and hardening at 230 ° C. for 60 minutes was 1.58 (D line 589 nm).

  A2: B3: C: D: E in the above weight ratio of A2, B3, C, D, E is 4.5: 2: 0.45: 21: 2 and mixed and stirred for 3 hours with a medialess disperser. A resin composition for a light scattering layer was obtained. The viscosity of the composition at this time was 14 cp / 25 ° C.

(Preparation of colored pixel material / colored composition)
[Pigment production example R2]
100 parts of diketopyrrolopyrrole red pigment PR254 ("Irgafoa Red B-CF" manufactured by Ciba Specialty Chemicals; R-1), 18 parts of dye derivative (D-1), 1000 parts of crushed salt, and 120 parts of diethylene glycol Was charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded at 60 ° C. for 10 hours.

  The mixture was added to 2000 parts of warm water, heated to about 80 ° C. and stirred with a high speed mixer for about 1 hour to form a slurry, filtered and washed repeatedly to remove salt and solvent, and then at 80 ° C. for 24 hours. Dried to obtain 115 parts of a salt milled pigment (R2).

[Pigment production example R3]
100 parts of anthraquinone red pigment PR177 (“Chromophthal Red A2B” manufactured by Ciba Specialty Chemicals), 8 parts of a dye derivative (D-2), 700 parts of crushed salt, and 180 parts of diethylene glycol are made of 1 gallon kneader made of stainless steel (Inoue Seisakusho) And kneaded at 70 ° C. for 4 hours. The mixture was put into 4000 parts of warm water, heated to about 80 ° C., stirred with a high speed mixer for about 1 hour to form a slurry, filtered and washed with water to remove salt and solvent, and then at 80 ° C. for 24 hours. Drying gave 102 parts of salt milled pigment (R3).

[Pigment production example R4]
A sulfonation flask was charged with 170 parts of tert-amyl alcohol under a nitrogen atmosphere, 11.04 parts of sodium was added, and the mixture was heated to 92-102 ° C. The molten sodium was kept at 100-107 ° C. overnight with vigorous stirring.

  A solution prepared by dissolving 44.2 parts of 4-chlorobenzonitrile and 37.2 parts of diisopropyl succinate in 50 parts of tert-amyl alcohol at 80 ° C. was dissolved in 80 to 98 ° C. Introduced over time. After the introduction, the reaction mixture was further stirred at 80 ° C. for 3 hours, and 4.88 parts of diisopropyl succinate was added dropwise at the same time.

  The reaction mixture was cooled to room temperature and added to a 20 ° C. mixture of 270 parts of methanol, 200 parts of water, and 48.1 parts of concentrated sulfuric acid and stirring was continued at 20 ° C. for 6 hours. The obtained red mixture was filtered, and the residue was washed with methanol and water and then dried at 80 ° C. to obtain 46.7 parts of a red pigment (R4).

[Pigment production example G2]
In a molten salt of 200 ° C. of 356 parts of aluminum chloride and 6 parts of sodium chloride, 46 parts of zinc phthalocyanine was dissolved, cooled to 130 ° C., and stirred for 1 hour. The reaction temperature was raised to 180 ° C., and bromine was added dropwise at 10 parts per hour for 10 hours. Thereafter, chlorine was introduced at 0.8 parts per hour for 5 hours.

  The reaction solution was gradually poured into 3200 parts of water, then filtered and washed with water to obtain 107.8 parts of a crude zinc halide phthalocyanine pigment. The average number of brominations contained in one molecule of the crude zinc halide phthalocyanine pigment was 14.1 and the average number of chlorine was 1.9. In this example, the bromination number is not limited.

  120 parts of the obtained crude zinc halide phthalocyanine pigment, 1600 parts of crushed salt and 270 parts of diethylene glycol were charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) and kneaded at 70 ° C. for 12 hours.

  The mixture was poured into 5000 parts of warm water, stirred at a high speed mixer for about 1 hour while being heated to about 70 ° C. to form a slurry, filtered and washed repeatedly to remove salt and solvent, and then at 80 ° C. for 24 hours. Drying gave 117 parts of salt milled pigment (G2).

[Pigment production example Y2]
A separable flask was charged with 150 parts of water, and further stirred with 63 parts of 35% hydrochloric acid to prepare a hydrochloric acid solution. While paying attention to foaming, 38.7 parts of benzenesulfonyl hydrazide was charged, and ice was added until the liquid temperature became 0 ° C. or lower. After cooling, 19 parts of sodium nitrite was charged over 30 minutes, stirred for 30 minutes at 0 to 15 ° C., and then sulfamic acid was charged until no coloration was observed on the potassium iodide starch paper.

  Next, after adding 25.6 parts of barbituric acid, it heated up to 55 degreeC and stirred as it was for 2 hours. Next, 25.6 parts of barbituric acid was added, the temperature was raised to 80 ° C., and then sodium hydroxide was added until the pH reached 5. Furthermore, after stirring at 80 degreeC for 3 hours, temperature was lowered | hung to 70 degreeC, it filtered, and warm water washing was performed.

  The obtained press cake was reslurried in 1200 parts of warm water, and then stirred at 80 ° C. for 2 hours. Thereafter, filtration was performed at the same temperature, and washing with 2000 parts of water at 80 ° C. was performed with warm water, and it was confirmed that benzenephonamide was transferred to the filtrate side. The obtained press cake was dried at 80 ° C. to obtain 61.0 parts of disodium azobarbituric acid.

  Next, 200 parts of water was charged into a separable flask, and 8.1 parts of the obtained disodium azobarbituric acid powder was added and dispersed while stirring. After uniformly dispersing, the solution was heated to 95 ° C., and 5.7 parts of melamine and 1.0 part of diallylaminomelamine were added. Further, a green solution obtained by dissolving 6.3 parts of cobalt (II) chloride hexahydrate in 30 parts of water was added dropwise over 30 minutes. After completion of the dropwise addition, complexation was performed at 90 ° C. for 1.5 hours.

  Thereafter, the pH was adjusted to 5.5, 20.4 parts of xylene, 0.4 part of sodium oleate, and 16 parts of water were previously stirred to add 20.4 parts of an emulsion, and further heated for 4 hours. Stir. After cooling to 70 ° C., it was quickly filtered, and warm water washing was repeated at 70 ° C. until the inorganic salt could be washed.

  Thereafter, 14 parts of an azo yellow pigment (Y2) was obtained through drying and grinding processes.

[Pigment production example B2]
100 parts of copper phthalocyanine blue pigment PB15: 6 (“Rionol Blue ES” manufactured by Toyo Ink Manufacturing Co., Ltd.), 800 parts of crushed salt, and 100 parts of diethylene glycol were charged into a stainless steel 1 gallon kneader (manufactured by Inoue Seisakusho) at 70 ° C. And kneaded for 12 hours.

  The mixture was poured into 3000 parts of warm water, stirred at a high speed mixer for about 1 hour while being heated to about 70 ° C. to form a slurry, filtered and washed repeatedly to remove salt and solvent, and then at 80 ° C. for 24 hours. Dried to obtain 98 parts of salt milled pigment (B2).

[Pigment production example V2]
300 parts of LIONOGEN VIOLET RL (manufactured by Toyo Ink Manufacturing Co., Ltd.) was added to 3000 parts of 96% sulfuric acid, stirred for 1 hour, and poured into water at 5 ° C. After stirring for 1 hour, the mixture was filtered, washed with warm water until the washing solution became neutral, and dried at 70 ° C.

  120 parts of the obtained acid pasting pigment, 1600 parts of sodium chloride, and 100 parts of diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) were charged into a stainless gallon kneader (manufactured by Inoue Seisakusho) and kneaded at 90 ° C. for 18 hours. Next, this mixture is poured into about 5 liters of warm water, heated to about 70 ° C. and stirred with a high speed mixer for about 1 hour to form a slurry, then filtered and washed to remove sodium chloride and diethylene glycol, It was dried at 80 ° C. for 24 hours to obtain 118 parts of a salt milled pigment (V2).

(Preparation of resin solution (P2))
A reaction vessel was charged with 800 parts of cyclohexanone, heated to 100 ° C. while injecting nitrogen gas into the vessel, and a mixture of the following monomer and thermal polymerization initiator was added dropwise at the same temperature over 1 hour to carry out a polymerization reaction. .

Styrene 70.0 parts Methacrylic acid 10.0 parts Methyl methacrylate 65.0 parts Butyl methacrylate 65.0 parts Azobisisobutyronitrile 10.0 parts After dropwise addition, the mixture is further reacted at 100 ° C for 3 hours, and then azo A solution obtained by dissolving 2.0 parts of bisisobutyronitrile in 50 parts of cyclohexanone was added, and the reaction was further continued at 100 ° C. for 1 hour to synthesize a resin solution.

  After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and cyclohexanone was added to the previously synthesized resin solution so that the nonvolatile content was 20%. An acrylic resin solution (P2) was prepared.

(Preparation of pigment dispersion and coloring composition)
The mixture (parts by weight) shown in Table 3 below was uniformly stirred and mixed, then dispersed with a sand mill for 5 hours using zirconia beads having a diameter of 1 mm, and then filtered through a 5 μm filter to obtain red, green, and blue A pigment dispersion was obtained.

Thereafter, as shown in Table 4 below, a mixture of a pigment dispersion acrylic resin solution (P2), a monomer, a polymerization initiator, a sensitizer, an organic solvent, and the like is mixed and stirred, then filtered through a 5 μm filter, and red, green And blue colored compositions were obtained. In the following examples, red pixels, green pixels, and blue pixels were formed using the colored composition shown in Table 4 below.

  Hereinafter, based on Example 1, this invention is demonstrated in detail.

[Example 1]
(Production of color filter substrate)
The production of the color filter substrate according to Example 1 will be described with reference to FIGS.

  A frame-shaped light shielding layer 2 and a pedestal 4 shown in FIGS. 1, 3 and 6 were formed on a transparent substrate 1 made of glass using the black composition described above. The thickness of the light shielding layer 2 was 1.6 μm, and the thickness of the base 4 was 0.6 μm. The light shielding layer 2 and the pedestal 4 are coated with the above-described black composition, dried, and then used with a gray-tone photomask (a photomask having a difference in transmittance between the light shielding layer pattern and the pedestal pattern). The film was formed on the transparent substrate 1 by a film hardening process by repeated exposure / development and heat treatment.

  Next, the spacer 5 was formed on the transparent substrate 1 by stacking the red pixel R, the green pixel G, the blue pixel B, the red stacked portion 5R, the green stacked portion 5G, and the blue stacked portion 5B. The exposure mask for forming colored pixels and spacers including the colored pixels in the reflective portion shown in FIG. 1 is a gray-tone photomask (a photomask in which the transmission pattern of the colored pixels and the reflective portion pattern are provided with different transmittances). Was used. As a result, a concave portion was formed in the reflective portion of the colored pixel.

  The film thickness of the colored layer (red pixel 3R, green pixel 3G, blue pixel 3B) formed directly on the transparent substrate 1 was set to 3.2 μm ± 0.2 μm. The film thickness of the colored pixel in the reflective part (concave part) was 1.6 μm ± 0.2 μm. In this embodiment, since the colored pixel wall having a height of about 1.6 μm is formed so as to surround the concave portion that is the reflective portion of the colored pixel, the landing of the ink droplets in the alignment film formation by ink jet shown below. Sometimes, the alignment film can be formed by applying ink droplets without flowing out of the recess.

  Next, as a pretreatment before forming the retardation layer 11, an alignment treatment was performed as follows. That is, as a pretreatment of the colored pixel surface for forming the retardation layer 11, a viscosity-adjusted alignment film material Sunever manufactured by Nissan Chemical Industries, Ltd. is used, and selectively applied to the reflective portion colored pixels by the inkjet coating apparatus. Were discharged so that the dry film thickness was 0.1 μm.

  In order to discharge accurately without inkjet non-ejection, misdirection, and mist, it is necessary to control the rheological characteristics during non-ejection. The rheological properties of the ink ejected into the ink jet have excellent discharge properties. The initial value of the complex viscosity of the ink at 23 to 25 ° C. when the frequency is changed from 100 to 0.1 Hz is 20 mPa · s or less. The maximum value is 1000 mPa or less, and the tangent loss at a frequency of 10 Hz to 50 Hz is 1 to 20. The ejection amount from the inkjet nozzle was one ejection per pixel within a range of 2 to 10 pl (picoliter).

  Furthermore, after heating and drying at 90 ° C. for 1 minute on a hot plate, the film was baked at 260 ° C. for 40 minutes in a clean oven to form a film. Subsequently, a rubbing process was performed on the substrate in a certain direction to make a pretreatment.

  A phase difference layer 11 having a phase difference function for changing a quarter wavelength, which will be described in detail below, was formed with a film thickness of 1.6 μm ± 0.1 μm on the pre-treated reflective portion colored pixels. That is, a dry film is formed on a colored pixel that is a retardation layer and is a mixture of the following composition that is stirred and mixed so as to be uniform and filtered through a 0.6 μm filter and pre-treated with a polymerizable liquid crystal compound. The film was applied to a thickness of 1.6 μm and dried by heating at 90 ° C. for 2 minutes on a hot plate to obtain a liquid crystal alignment substrate.

Horizontally-aligned polymerizable liquid crystal 39.7 parts (“Palocolor LC 242” manufactured by BASF Japan Ltd.)
Photopolymerization initiator 0.3 part ("Irgacure 907" manufactured by Ciba Specialty Chemicals Co., Ltd.)
Surfactant 6.0 parts ("BYK111" 2% cyclohexanone solution manufactured by Big Chemie)
154.0 parts of cyclohexanone Next, the substrate coated with the polymerizable liquid crystal compound was exposed to ultraviolet rays for each colored pixel area of the reflection part through a photomask using an exposure machine using a semiconductor laser as a light source. The dose of ultraviolet rays, by changing the number of shots of the laser, 500 mJ / cm ² in the red pixel region, 200 mJ / cm ² in the green pixel region, a blue pixel regions respectively exposed as 5 mJ / cm ^2, at further development A retardation layer pattern was formed.

  Subsequently, the substrate was placed in a clean oven and baked at 230 ° C. for 40 minutes to obtain a color filter substrate on which a retardation layer as a quarter wavelength layer was formed.

  When the total of the phase difference between the colored pixels and the retardation layer of the obtained color filter substrate was measured, the red pixel portion was 166 nm for light of wavelength 630 nm, the green pixel portion was 136 nm for light of wavelength 550 nm, and the blue pixel portion was wavelength 112 nm in 450 nm light. That is, it can be seen that the sum of the phase differences of the colored pixel and the retardation layer satisfies the relationship of the sum of the phase differences in the red pixel ≧ the sum of the phase differences in the green pixel ≧ the sum of the phase differences in the blue pixel.

The results are shown in Table 5 below.

  The retardation layer 11 ′ was also formed on the frame-shaped light shielding layer 2 with the same frame-shaped pattern. The total film thickness of the light shielding layer 2 and the retardation layer 11 ′ on the light shielding layer is about 3.2 μm, which is substantially the same as the film thickness of the green pixel 3 </ b> G.

Next, a light scattering layer (cell gap adjusting layer) 12 was formed to a thickness of 1.9 μm using the light scattering layer composition. The forming method used the photomask which has the pattern of the light-scattering layer 12, performed 200 mJ / cm < ² > ultraviolet exposure, developed with the alkali developing solution, and hardened | cured by heat processing for 40 minutes at 230 degreeC. This exposure and heat treatment lead to stabilization of the additional hard film of the retardation layer already disposed under the light scattering layer 12. By the lamination of the light scattering layer 12, the oxygen inhibition of the retardation layer is eliminated and the film can be stabilized again by a hardening process including ultraviolet exposure. In this embodiment, the concave portions are provided in the colored pixels in advance, and then the hardening is performed by the heat treatment of the retardation layer. Therefore, the retardation layer can be satisfactorily formed without being deformed regardless of the difference in exposure amount. did it.

  The protrusion height d on the pedestal 4 shown in FIG. 4 was as low as 0.1 μm on the blue pixel side and 0.14 μm on the green pixel side, and the flatness was good.

  Also, the size of the bottom side of the spacer 5 shown in FIG. 3 was 25 μm, and the overall height of the laminated colored layer constituting the spacer 5 was about 3.9 μm. Next, a transparent conductive film was laminated so as to cover the effective display area of the color filter using a sputtering apparatus.

  The liquid crystal thickness of the target liquid crystal display device is 3.8 μm. The thickness of the liquid crystal layer on the reflection portion shown in FIG. 18 described later was 1.8 μm.

[Example 2]
(Production of color filter substrate)
The color filter substrate according to this embodiment will be described with reference to FIG. 12 which is a plan view, FIG. 13 which is a partial plan view (green pixel), and FIG. 14 which is a cross-sectional view thereof. The present embodiment is different from the first embodiment in that a black matrix is formed, a transparent resin is used instead of a light scattering layer as a cell gap adjusting layer, and a spacer is disposed at the center of a colored pixel.

  The black matrix 38 shown was formed on the transparent substrate 1 which is glass using the black composition described above. The thickness of the black matrix 38 was 0.6 μm. The black matrix 38 and the light shielding layer 2 are coated with the above-described black composition and dried, and then a gray-tone photomask (a photomask having a transmittance difference between the light shielding layer 2 and the black matrix 38) is applied. The film was formed on the transparent substrate 1 by a film hardening process by one exposure / development and heat treatment.

  Further, the red pixel 3R, the green pixel 3G, and the blue image 3B were formed on the transparent substrate 1 on which the black matrix 38 was formed. The film thickness of the colored layer (red pixel 3R, green pixel 3G, blue pixel 3B) formed directly on the transparent substrate 1 made of glass was 3.2 μm ± 0.2 μm.

  A phase difference layer 41 having a phase difference function for changing a quarter wavelength is formed with a film thickness of 1.6 μm ± 0.1 μm in the reflection portion (concave portion) 40 of the green pixel 3G shown in FIG. 13 and FIG. . The pretreatment of the colored pixel surface for aligning the retardation layer 41 and imparting the retardation function, the formation of the retardation layer 41, and the materials used for these were the same as in Example 1.

  Next, a cell gap adjusting layer 45 having a film thickness of 1.9 μm was formed on the retardation layer 41 using an acrylic photosensitive resin capable of alkali development. A cell gap adjusting layer was also formed on the frame-shaped light shielding layer 2 in the same frame-shaped pattern. The total film thickness of the light shielding layer and the cell gap adjusting layer on the light shielding layer is about 3.2 μm, and is substantially the same as the film thickness of the green pixel 3G.

  Next, a transparent conductive film 49 was laminated so as to cover the effective display area of the color filter using a sputtering apparatus.

  A spacer 46 and a sub-spacer 47 each having a trapezoidal cross section were formed on the transparent conductive film 49. A gray-tone photomask was used as an exposure mask for forming the spacer 46 and the sub-spacer 47. The height of the sub-spacer 47 was 0.3 μm lower than the total height of the spacer 46 and the cell gap adjusting layer 45. The sub spacer 47 was formed only on the light shielding layer. Further, the size of the bottom side of the spacer 46 was 15 μm and the height was about 2 μm. In addition, the thickness of the liquid crystal layer of the target liquid crystal display device is 3.8 μm.

  Also in this example, as in Example 1, good results could be obtained.

Example 3
(Production of color filter substrate)
An embodiment will be described based on FIG. 8 which is a schematic plan view of a color filter substrate of the present invention, and also using FIGS. 2 and 3 which are partial sectional views thereof.

  The light shielding layer 2 and the base 4 shown in FIGS. 8 and 2 were formed on the transparent substrate 1 made of glass using the black composition described above. The thickness of the light shielding layer 2 was 1.6 μm, and the thicknesses of the black matrix 8 and the pedestal 4 were 0.6 μm. The light shielding layer 2, the black matrix 8 and the pedestal 4 are coated with the above-described black composition and dried, and then a gray-tone photomask (a photomask having a transmittance difference between the light shielding layer pattern and the pedestal pattern). The film was formed on the transparent substrate 1 by a film hardening process by one exposure / development and heat treatment.

  Next, as illustrated in FIG. 3, the light shielding layer 2, the red pixel 3 </ b> R, the green pixel 3 </ b> G, the blue pixel 3 </ b> B, and the spacer 5 and the sub-spacer 6 formed by stacking colored layers were formed on the transparent substrate 1. As an exposure mask for forming the spacer 5 and the sub-spacer 6, a gray-tone photomask whose pattern portion has a low transmittance was used.

  The thickness of the colored layer (red pixel 3R, green pixel 3G, blue pixel 3B) portion formed directly on the transparent substrate 1 was set to 3.2 μm ± 0.2 μm.

  In the reflective portion (concave portion) of the colored pixel shown in FIG. 2, a retardation layer 11 having a retardation function of ½ wavelength is formed with a film thickness of 2.6 μm ± 0.15 μm as shown in Table 6 below. Formed. The pretreatment of the colored pixel surface for aligning the phase difference layer 11 and imparting the phase difference function was the same as in Example 1. The phase difference amount corresponding to each colored pixel was adjusted by the exposure amount. The polymerizable liquid crystal composition to be the retardation layer 11 has the following composition.

Horizontally-aligned polymerizable liquid crystal 49.5 parts (Dainippon Ink & Chemicals, Inc. “UCL-017”)
Photopolymerization initiator 0.5 part ("Irgacure OXE01" manufactured by Ciba Specialty Chemicals)
Surfactant 2.0 parts ("BYK330" 2% cyclohexanone solution manufactured by Big Chemie)
Cyclohexanone 148.0 parts

  Next, a cell gap adjusting layer 15 having a film thickness of 0.9 μm was formed using an acrylic photosensitive resin capable of alkali development. A cell gap adjusting layer 15 ′ was also formed in the same pattern on the frame-shaped light shielding layer 2 shown in FIG. 2. The height and shape of the spacer are the same as in Example 1.

  In the color filter substrate obtained in Example 3 above, the thickness of the retardation layer 11 is 2.6 μm, and is formed in the concave portion of a colored pixel (for example, the green pixel 3G) having a thickness of 3.2 μm. Therefore, the actual structure is as shown in FIG.

  Next, using a sputtering apparatus, a transparent conductive film was laminated so as to cover the effective display area of the color filter to obtain a color filter substrate.

  Also in this example, as in Example 1, good results could be obtained.

Example 4
With reference to FIG. 16, the color filter substrate according to the present embodiment will be described.

  In this example, the transparent substrate 1 on which the transparent conductive film 59 was previously formed was used. On the transparent conductive film 59, a black matrix 58, colored pixels 3R, 3G, and 3B, a cell gap adjusting layer, a spacer 55, and a sub-spacer 56 were formed in the same manner as in Example 2. In the center of each colored pixel, a black matrix 58 'having an image line width of 6 μm is arranged in the longitudinal direction of the colored pixel. Illustration of the cell gap adjusting layer is omitted.

  The transparent conductive film 59 had a thickness of 0.14 μm and was formed with a sputtering apparatus.

  Also in this example, as in Example 1, good results could be obtained.

Example 5
Embodiment 5 which is a color filter substrate will be described with reference to FIG.

  In this embodiment, after forming the black matrix 68 first, the transparent conductive film 69 is formed. On the transparent conductive film 69, the colored pixels 3R, 3G, and 3B, the cell gap adjusting layer, the spacer 65, and the sub-spacer 66 were formed in the same manner as in Example 2. A black matrix 68 'having an image line width of 6 μm is arranged in the center of the colored pixels 3R, 3G, and 3B in the longitudinal direction of the colored pixels. Illustration of the cell gap adjusting layer is omitted.

  The transparent conductive film 69 had a thickness of 0.15 μm and was formed with a sputtering apparatus.

  Also in this example, as in Example 1, good results could be obtained.

Example 6
(Production of liquid crystal display device)
The color filter substrate 31 and the TFT substrate 32 produced in Example 1 were arranged to face each other, and a liquid crystal layer 33 was sandwiched between them to obtain a liquid crystal display device. In addition, illustration of the polarizing film, retardation film, and alignment film was abbreviate | omitted. Reference numerals 34 and 35 denote a TFT element and a pixel electrode, respectively.

  In this embodiment, the color filter substrate 31 has the same thickness as that of the colored layer 3G, which is a green pixel, combined with the light shielding layer and the cell gap regulating layer, and has no excessive protrusion structure, so that it is smooth and uniform. Liquid crystal can be filled, and the image display is very uniform and good. A high-quality liquid crystal display device free from light leakage without any disturbance of the liquid crystal alignment around the colored pixels or at the boundary between the light shielding layer and the display region was obtained.

  A partial enlarged view of the liquid crystal display device in the vicinity of the TFT element 34 shown in FIG. 18 is shown in FIG. 19 (the light scattering layer and the cell gap regulating layer are not shown). According to the present embodiment, since there is a retardation layer provided in the reflection portion, there is no difference in display quality between the reflection portion and the transmission portion, and a high transmittance liquid crystal display device can be obtained.

Example 7
(Production of liquid crystal display device)
Please refer to FIG. A liquid crystal display device according to this embodiment will be described.

  In this example, a liquid crystal display device was manufactured by using an array substrate 72 having comb-like pixel electrodes 82 with a common electrode 83 and an insulating layer interposed therebetween, and a color filter substrate 73 having the same configuration as that of Example 5. A polarizing plate, a retardation plate, and a backlight source attached to the outer surface of the liquid crystal display device are not shown. FIG. 20 is a cross-sectional view of the transmissive part of the green pixel, and the reflective part is not shown.

  In the color filter substrate 73 used in this embodiment, since the transparent conductive film 79 is formed on the black matrix 78, when the liquid crystal display device is configured, the array substrate 72 has a thickness equivalent to the thickness of the black matrix 78. There is an advantage that the formation of the oblique electric field becomes smooth as shown by the arrow in FIG. In order to form an oblique electric field with the pixel electrode 82, the thickness of the black matrix can be adjusted.

  The liquid crystal display device according to this example was excellent in that the image display was extremely uniform. A high-quality liquid crystal display device free from light leakage without any disturbance of the liquid crystal alignment around the colored pixels or at the boundary between the light shielding layer and the display region was obtained.

  The common electrode may be formed of a solid film for each pixel or may be formed in a comb shape. A slit-shaped opening may be formed in the transparent conductive film. The common electrode and the pixel electrode may be formed of a metal thin film such as an aluminum alloy, or may be formed of a transparent conductive thin film such as ITO.

  Moreover, the transparent conductive film described in the above-described Example 4, Example 5, and Example 7 may be dropped to the ground when the liquid crystal is driven, or may have the same potential as the common electrode.

The present invention is not limited to the vertical alignment method for the liquid crystal alignment method. For example, various retardation functions can be obtained by changing the thickness or Δnd of the retardation layer, or various retardation layers can be obtained by adjusting the alignment by photo-orientation or rubbing. It can correspond to. The dielectric anisotropy of the liquid crystal material that can be employed in the present invention may be a positive material or a negative material.
Hereinafter, the invention described in the initial claims is appended.
[1]
On the transparent substrate, a light shielding layer is disposed on the outer periphery of the effective display area, and colored pixels including a red pixel, a green pixel, and a blue pixel, a spacer, a first retardation layer, and a transparent conductive film are formed in the effective display area. In the color filter substrate for the transflective liquid crystal display device,
A concave portion is formed in each of the colored pixels, and the first retardation layer is provided in the concave portion, and incident light converted into linearly polarized light is provided in the thickness direction of the first retardation layer. It has the function of rotating 90 degrees of polarized light by one round of transmission, and the thickness direction retardation of the colored pixel in each recess and the thickness direction retardation of the first retardation layer in the recess A color filter substrate for a transflective liquid crystal display device, characterized in that the total has a relationship of total phase difference in red pixels ≧ total phase difference in green pixels ≧ total phase difference in blue pixels.
[2]
[1] The phase difference in the thickness direction of the colored pixels of the plurality of colors is in the relationship of the thickness direction phase difference of the red pixel ≧ the thickness direction phase difference of the green pixel ≧ the thickness direction phase difference of the blue pixel. A color filter substrate for a transflective liquid crystal display device as described.
[3]
The color filter substrate for a transflective liquid crystal display device according to [1] or [2], wherein the green pixel contains zinc halide phthalocyanine as a main coloring material.
[4]
Any one of [1] to [3], wherein the ratio of the thickness of the colored pixel in the concave portion to the thickness of the colored pixel other than the concave portion is in a range of ½ to ¼. A color filter substrate for a transflective liquid crystal display device as described in 1.
[5]
The color filter substrate for a transflective liquid crystal display device according to any one of [1] to [4], wherein a first cell gap adjusting layer is formed on the first retardation layer.
[6]
The difference in height between the surface of the first cell gap regulating layer and the surface of the colored pixel other than the concave portion is approximately ½ of the thickness of the liquid crystal layer of the liquid crystal display device [5] A color filter substrate for a transflective liquid crystal display device as described in 1.
[7]
The color filter substrate for a transflective liquid crystal display device according to [5] or [6], wherein the first cell gap adjusting layer is a light scattering layer.
[8]
Any one of [1] to [7], further comprising a black matrix made of the same material as the light-shielding layer, which is arranged so as to partition the colored pixels in an effective display area on the transparent substrate. A color filter substrate for a transflective liquid crystal display device as described in 1.
[9]
The color filter substrate for a transflective liquid crystal display device according to [8], wherein the thickness of the black matrix is thinner than the thickness of the light shielding layer.
[10]
The color filter substrate for a transflective liquid crystal display device according to [8] or [9], wherein the transparent conductive film is disposed between the black matrix and the transparent substrate.
[11]
The color filter substrate for a transflective liquid crystal display device according to [8] or [9], wherein the transparent conductive film is disposed between the black matrix and the colored pixels.
[12]
A second cell gap adjusting layer stacked on the light shielding layer; and a total film thickness of the light shielding layer and the second cell gap adjusting layer being substantially the same as the thickness of the green pixel. The color filter substrate for a transflective liquid crystal display device according to any one of [1] to [11].
[13]
A second retardation layer laminated on the light shielding layer is further provided, and the total thickness of the light shielding layer and the second retardation layer is substantially the same as the thickness of the green pixel. The color filter substrate for a transflective liquid crystal display device according to any one of [1] to [12].
[14]
The transflective device according to any one of [1] to [13], wherein the spacer is an alignment control structure that is disposed in the center of the colored pixel and also serves as a liquid crystal alignment control function. Type color filter substrate for LCD.
[15]
The color filter substrate for a transflective liquid crystal display device according to any one of [1] to [14], wherein an alignment control protrusion made of the same material as the spacer is disposed on a colored pixel.
[16]
Any one of [1] to [9], [12] to [15], wherein the transparent conductive film is laminated on at least a plurality of colored pixels and the first cell gap adjusting layer. A color filter substrate for a transflective liquid crystal display device as described in 1.
[17]
The film thickness of the colored pixels of the plurality of colors is in a relationship of red pixel film thickness ≦ green pixel film thickness ≦ blue pixel film thickness, according to any one of [1] to [16] Color filter substrate for transflective liquid crystal display.
[18]
A transflective liquid crystal display device comprising the color filter substrate for a transflective liquid crystal display device according to any one of [1] to [17].
[19]
In the method for producing a color filter substrate for a transflective liquid crystal display device according to any one of [1] to [17],
Forming recesses in the plurality of colored pixels by a photolithography technique using a gray-tone photomask; and
A step of forming an alignment film for aligning the retardation layer in the recess by an inkjet method
A method for producing a color filter substrate for a transflective liquid crystal display device.

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Light-shielding layer 3R ... Red pixel 3G ... Green pixel 3B ... Blue pixel 4, 4 '... Base 5,55 ... Spacer 5R, 5G, 5B ... Colored laminated layers 6, 56 ... Sub-spacers 7 ... Protrusions 8, 38, 58, 58 ', 68, 68', 78 ... Black matrix 9, 49, 59, 69, 79 ... -Transparent conductive film 10 ... Concave part 11, 11 ', 41 ... Retardation layer 12 ... Light scattering layer (cell gap adjustment layer)
13 ... Amorphous fine particles 14 ... Matrix resin (transparent resin)
15, 15 ', 45 ... cell gap adjusting layer 22 ... thick colored pixel 23 ... thin colored pixel 31, 73 ... color filter substrate 32 ... TFT substrate 33 ... liquid crystal layer 34 ..TFT elements 35, 82 ... Pixel electrodes 46 ... Spacers 47 ... Sub-spacers 72 ... Array substrates 83 ... Common electrodes

Claims (19)

On the transparent substrate, a light shielding layer is disposed on the outer periphery of the effective display area, and colored pixels including a red pixel, a green pixel, and a blue pixel, a spacer, a first retardation layer, and a transparent conductive film are formed in the effective display area. In the color filter substrate for the transflective liquid crystal display device,
A concave portion is formed in each of the colored pixels, and the first retardation layer is provided in the concave portion, and incident light converted into linearly polarized light is provided in the thickness direction of the first retardation layer. It has the function of rotating 90 degrees of polarized light by one round of transmission, and the thickness direction retardation of the colored pixel in each recess and the thickness direction retardation of the first retardation layer in the recess A color filter substrate for a transflective liquid crystal display device, characterized in that the total has a relationship of total phase difference in red pixels ≧ total phase difference in green pixels ≧ total phase difference in blue pixels.   The thickness direction retardation of the colored pixels of the plurality of colors has a relationship of red pixel thickness direction phase difference ≧ green pixel thickness direction phase difference ≧ blue pixel thickness direction phase difference. A color filter substrate for a transflective liquid crystal display device as described.   The color filter substrate for a transflective liquid crystal display device according to claim 1, wherein the green pixel contains zinc halide phthalocyanine as a main color material.   The ratio of the thickness of the colored pixel in the concave portion to the thickness of the colored pixel other than the concave portion is in the range of 1/2 to 1/4. Color filter substrate for transflective liquid crystal display devices.   5. The color filter substrate for a transflective liquid crystal display device according to claim 1, wherein a first cell gap adjusting layer is formed on the first retardation layer. 6. The difference in height between the surface of the first cell gap adjusting layer and the surface of a colored pixel other than the concave portion is approximately ½ of the thickness of the liquid crystal layer of the liquid crystal display device. A color filter substrate for a transflective liquid crystal display device as described in 1.   The color filter substrate for a transflective liquid crystal display device according to claim 5 or 6, wherein the first cell gap adjusting layer is a light scattering layer.   8. The method according to claim 1, further comprising a black matrix made of the same material as that of the light shielding layer, which is arranged so as to partition the colored pixels in an effective display area on the transparent substrate. Color filter substrate for transflective liquid crystal display devices.   9. The color filter substrate for a transflective liquid crystal display device according to claim 8, wherein the thickness of the black matrix is thinner than the thickness of the light shielding layer.   The color filter substrate for a transflective liquid crystal display device according to claim 8, wherein the transparent conductive film is disposed between the black matrix and the transparent substrate.   The color filter substrate for a transflective liquid crystal display device according to claim 8 or 9, wherein the transparent conductive film is disposed between the black matrix and the colored pixels.   A second cell gap adjusting layer stacked on the light shielding layer; and a total film thickness of the light shielding layer and the second cell gap adjusting layer being substantially the same as the thickness of the green pixel. 12. The color filter substrate for a transflective liquid crystal display device according to claim 1, wherein the color filter substrate is a transflective liquid crystal display device.   A second retardation layer laminated on the light shielding layer is further provided, and the total thickness of the light shielding layer and the second retardation layer is substantially the same as the thickness of the green pixel. A color filter substrate for a transflective liquid crystal display device according to any one of claims 1 to 12.   The transflective liquid crystal according to any one of claims 1 to 13, wherein the spacer is an alignment control structure that is disposed in the center of the colored pixel and also serves as a liquid crystal alignment control. Color filter substrate for display devices.   15. The color filter substrate for a transflective liquid crystal display device according to claim 1, wherein an alignment control protrusion made of the same material as the spacer is disposed on the colored pixel.   16. The transflective type according to claim 1, wherein the transparent conductive film is laminated on at least a plurality of colored pixels and the first cell gap adjusting layer. Color filter substrate for liquid crystal display devices.   17. The transflective according to claim 1, wherein the thicknesses of the colored pixels of the plurality of colors are in the relationship of the thickness of the red pixel ≦ the thickness of the green pixel ≦ the thickness of the blue pixel. Type color filter substrate for LCD. A transflective liquid crystal display device comprising the color filter substrate for a transflective liquid crystal display device according to claim 1. A method for producing a color filter substrate for a transflective liquid crystal display device according to any one of claims 1 to 17,
A step of forming recesses in the plurality of colored pixels by a photolithography technique using a gray-tone photomask; and a step of forming an alignment film in the recesses for aligning a retardation layer by an inkjet method. A method for producing a color filter substrate for a transflective liquid crystal display device.

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