JP2009258696A - Color filter substrate and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter substrate and a liquid crystal display device that are reduced in light leakage at black display and high in contrast, thereby achieving high quality display. <P>SOLUTION: The color filter substrate is formed of a black matrix on a transparent substrate and a coloring pixel consisting of a coloring film at a polygonal opening of the black matrix. A liquid crystal compound is filled in a space held by a fixing spacer between the color filter substrate and a counter substrate. A polarizing plate is disposed such that each polarizing axis is perpendicular to sides opposite to the sides in contact with the liquid crystal compound of both substrates. Thus, the color filter substrate is used for a normally black active matrix liquid crystal display. A minimum value CRmin of contrast is ≥2,000 when measured by rotating the color filter substrate up to 0-360° with respect to a polarizing axis of a linear polarizer whose extinction ratio at 410 nm is ≥5.0×10<SP>3</SP>and ≤5.0×10<SP>4</SP>. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a color liquid crystal display device including a color filter and a polarizing plate.

  The display characteristics of liquid crystal display devices are evaluated based on the color reproduction range, luminance, viewing angle, contrast, response speed, and the like, and development of improving the characteristics is being energetically advanced. Contrast, which is one of the display characteristics, is defined by the value obtained by dividing the luminance of white display by the luminance of black display. The higher the contrast, the blacker the black display, and the higher the quality display with a sense of depth and sharpness. .

  In order to improve the contrast of liquid crystal display devices, normally black liquid crystal displays such as IPS (in-plane switching system) and VA (vertical alignment) systems are effective, and their development and marketing are progressing. Also, the spacer used to define the thickness of the liquid crystal layer, the so-called cell gap, can be improved in contrast by using a patterned photosensitive resin and a fixed spacer instead of the conventional method of spraying resin beads. It has been. Furthermore, since the improvement of the polarization degree of the polarizing plate directly affects the improvement of the contrast, the development thereof is progressing. With respect to color filters, development of contrast enhancement centering on pigment miniaturization is in progress to suppress depolarization by pigment particles in the colored layer and reduce black light leakage (Patent Documents 1 and 2). .

  However, the improvement of the contrast of the liquid crystal display device is limited only by the refinement of the pigment, that is, the improvement of the contrast of the colored layer of the color filter, and it is necessary to further improve the contrast.

  One of the factors that lower the LCD contrast is the poor alignment of the liquid crystal due to the large surface step of the color filter. Colored pixels can be formed by forming a flattened film on the color filter or thinning the black matrix. Studies have been made to reduce the level difference caused by climbing (Patent Documents 3, 4, and 5).

  However, there is a problem that the LCD contrast does not improve even when a color filter with improved color layer contrast and reduced surface level difference is used, and is particularly noticeable in LCDs with high definition and narrow pixel pitch. It came.

Japanese Patent Laid-Open No. 08-171014 JP 2005-208397 A JP 2005-55747 A JP 09-304615 A JP 2004-93656 A

    The present invention provides a color filter substrate capable of providing a liquid crystal display device capable of high-quality display with little light leakage in black display, and a liquid crystal display device using the color filter substrate. For the purpose.

In order to achieve the above object, the present invention comprises the following constitution.
(1) A liquid crystal compound is placed in a space held by a fixed spacer between a color filter substrate in which a colored pixel made of a colored film is formed in an opening of a black matrix formed on a transparent substrate and a substrate facing the color filter substrate. Color filter substrate used in a normally black type active matrix liquid crystal display device in which polarizing plates are arranged so that the polarization axes thereof are orthogonal to each other on the opposite side of the surface in contact with the liquid crystal compound of both substrates In the above, the black matrix is a resin black matrix comprising at least a resin and a light-shielding agent, and the repeating pitch of the colored pixels is 70 μm or less, and the colored film has an opening in an inclined region of the colored film riding on the black matrix. An inclination angle θ of the inclined region rising from the transparent substrate is 15 ° or less. The color filter substrate.
(2) When measured by rotating the color filter substrate to 0 to 360 ° with respect to the polarization axis of the linearly polarizing plate having a depolarization ratio at 410 nm of 5.0 × 10 ³ or more and 5.0 × 10 ⁴ or less. The color filter substrate according to (1), wherein the minimum contrast value CRmin is 2000 or more.
(3) The color filter substrate according to (1) or (2), wherein the thickness of the black matrix layer is 1.0 μm or less.
(4) The color filter substrate according to any one of (1) to (3), wherein a transparent resin layer is provided on the colored layer. (5) The refractive index of the transparent resin layer is 1.55. The color filter substrate according to (4), which is in the range of 1.80 (6) The refractive index difference between the colored layer and the transparent resin layer is in the range of 0.005 to 0.20. The color filter substrate according to (4) or (5), wherein the black matrix contains at least a titanium compound as a light-shielding agent, according to any one of (1) to (6) The color filter substrate as described.
(8) The color filter substrate according to any one of (1) to (7), wherein the black matrix contains at least titanium nitride as a light shielding agent.
(9) A liquid crystal display device comprising the color filter substrate according to any one of (1) to (8).

  According to the color filter substrate of the present invention, a liquid crystal display device capable of high-quality display with little light leakage in black display and high contrast can be provided.

Sectional view of the color filter substrate of the present invention Schematic diagram of an apparatus for measuring contrast

  As a result of intensive studies on a color filter substrate capable of improving the contrast of a liquid crystal display device, the present inventors have found that this is possible by the following method.

  That is, in a space held by a fixed spacer between a color filter substrate in which a black matrix on a transparent substrate and colored pixels made of a colored film are formed in a polygonal opening of the black matrix and a substrate facing the color filter substrate. Used in a normally black type active matrix liquid crystal display device in which a liquid crystal compound is filled and a polarizing plate is arranged so that each polarization axis is orthogonal to the surface opposite to the surface in contact with the liquid crystal compound of both substrates. A color filter substrate, wherein the black matrix is a resin black matrix composed of at least a resin and a light-shielding agent, the repetition pitch of the colored pixels is 70 μm or less, and the colored layer formed on the transparent substrate is a black matrix In a tilted area that climbs up to the layer, against the transparent substrate in the tilted area that rises from the opening Oblique angle θ is that using a color filter substrate is 15 ° or less found to be effective in improving the contrast of a liquid crystal display device.

  This is a liquid crystal display device that employs a fixed spacer, normally black display method, and light leakage during black display is highly suppressed. Inclination of the pixel run-up portion of the colored layer on the black matrix layer of the color filter substrate This is because the relative arrangement between the surface and the deflection axis of the polarizing plate has been found to greatly affect the black display light leakage of the liquid crystal display device, that is, the contrast value.

  In other words, in a liquid crystal display device having either a bead spacer or a normally white display method that has been conventionally used, the amount of light leakage in black display is caused by the polarization axis of the polarizing plate and the inclination of the pixel landing portion of the colored layer. This is relatively larger than the amount of light leakage in black display due to the relative arrangement with the surface, and the effect of the present invention cannot be sufficiently obtained.

  As the black matrix layer in the color filter substrate of the present invention, it is important to use a resin black matrix obtained by applying and processing a black resin composition in which a light shielding agent is dispersed in a binder resin. In general, in addition to the resin black matrix, a thin film in which a metal or a metal compound such as chromium, nickel, or aluminum is formed by a vacuum film formation method such as a vapor deposition method or a sputtering method is used as the black matrix layer. However, when a metal thin film is used as the black matrix, the mechanism is unknown, but the angle formed between the inclined surface of the colored layer and the polarization axis of the linearly polarizing plate is (90 × n + 45) ° (n = 0, 1, 2, 3) is not preferable because the amount of light leakage, that is, the contrast decreases.

  Further, when the resolution of the liquid crystal display device and the color filter substrate is increased, the amount of the colored layer on the unit area increases, and the amount of light leakage in black display, that is, the decrease in contrast increases, and the display characteristics deteriorate significantly. Therefore, the effect of the present invention is more remarkably exhibited in a color filter substrate having a high resolution. Specifically, it is important that the pixel repeat pitch is 70 μm or less, and that the effect is further 40 μm or less. Become prominent. Here, the repetition pitch of pixels refers to the length of the short side width of pixels of a plurality of colors arranged periodically.

  Still further, in the color filter substrate of the present invention, in the inclined region where the colored layer formed on the transparent substrate rides on the black matrix layer, the inclined angle θ with respect to the transparent substrate of the inclined region rising from the opening is 15 ° or less. It is important that the angle is 10 ° or less. The “inclination angle θ in the inclined region where the colored layer runs on the black matrix layer” in the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view of a color filter substrate. The color filter substrate shown in FIG. 1 has a black matrix 3 on a transparent substrate 2 and a colored layer 4 provided on an opening of the black matrix and a part of the black matrix 3. The colored layer 4 is flat as shown in the figure on the opening of the black matrix 3, but an inclined region 7 is generated by running on the black matrix pattern as shown in the figure. An angle of the colored layer with respect to the transparent substrate in the inclined region is defined as θ. The inclination angle θ can be obtained by breaking the color filter substrate, observing the cross section with a transmission electron microscope or the like, and performing image analysis of the photographed photograph. When the inclination angle θ is larger than 15 °, the contrast of the color filter substrate is lowered by the relative arrangement of the inclined surface of the colored layer and the polarization axis deviation of the linear polarizing plate.

  Conventionally, the influence of the flatness of the color filter substrate on the decrease in contrast of the liquid crystal display device has been known, but the relationship between the relative arrangement of the inclined surface of the pixel-carrying portion of the colored layer and the polarization axis of the polarizing plate and the contrast. Is not known, and in the process of conceiving the present invention, the contrast was unexpectedly measured by changing the angle between the sufficiently flat color filter substrate on which the planarizing film was formed and the polarization axis. I found it to change. When the cause of this change was further examined, when the color filter substrate was rotated with respect to the polarization axis of the linearly polarizing plate and the contrast was measured, the contrast specifically decreased in the color filter substrate having a specific structure. Newly found. Furthermore, in a liquid crystal display device using a color filter substrate having a high contrast minimum CRmin when measured by rotating the color filter substrate from 0 to 360 ° with respect to the polarization axis of the linearly polarizing plate, good display characteristics are obtained. Has been found to be obtained.

  The contrast of the color filter substrate here means that the color filter substrate is sandwiched between a pair of linear polarizing plates and arranged in front of the backlight light source, and the luminance when measured with parallel Nicols is measured with orthogonal Nicols. It is calculated by the ratio with the luminance.

(Contrast) = (Luminance with parallel Nicols) / (Luminance with direct Nicols) (1)
In contrast measurement in the present invention, it is important to measure using a linearly polarizing plate having an extinction ratio at 410 nm of 5.0 × 10 ³ or more and 5.0 × 10 ⁴ or less. In the measurement using a low linearity, that is, a linear polarizing plate with a large amount of light leakage in the blue region, the influence of light leakage by the polarizing plate is greater than the light leakage on the color filter substrate, and accurate contrast cannot be measured. Examples of the linear polarizing plate having a depolarization ratio at 410 nm of 5.0 × 10 ³ or more and 5.0 × 10 ⁴ or less include POLAX38S manufactured by Luceo Corporation. Here, the extinction ratio refers to the ratio of the intensity of light transmitted in a direction perpendicular to the transmission intensity of light oscillating parallel to the main axis of the polarizing plate. The backlight light source used for measurement is not particularly limited, and specifically, a cold-cathode tube light source, an LED light source, or a continuous spectrum light source generally used in a liquid crystal display device is used. Can do.

  The contrast of the color filter substrate decreases due to various factors described later, and in particular, the angle formed by the inclined surface of the colored layer on the black matrix and the polarization axis of the linearly polarizing plate is (90 × n + 45) ° (n = 0, 1, 2, 3), the amount of light leakage increases, and the contrast of the color filter substrate decreases. Therefore, when the contrast is measured by rotating the color filter substrate with respect to the linear polarizing plate, the contrast value changes, and the contrast is measured by rotating the color filter substrate to 0 to 360 ° with respect to the linear polarizing plate. At this time, the maximum contrast value is CRmax, and the minimum contrast value is CRmin. In the color filter substrate of the present invention, the degree of CR reduction from CRmax is small, and as a result, CRmin is also a high value.

  In order to make the effect of the present invention more prominent, the minimum value CRmin of the color filter substrate is preferably 2000 or more, more preferably 3000 or more, and further preferably 4000 or more.

Examples of the color filter substrate and the liquid crystal display device of the present invention will be described in detail below, but the present invention is not limited thereto.
In the color filter substrate of the present invention, a black matrix layer is provided on a transparent substrate, and further, a colored layer of at least one color is applied and patterned on the transparent substrate, and the openings and a part on the black matrix are laminated. Become. Furthermore, a transparent resin layer may be formed on the color filter resurface.

  The transparent substrate used in the present invention is not particularly limited, and inorganic glass such as quartz glass, borosilicate glass, aluminosilicate glass, soda lime glass coated with silica on the surface, organic plastic film or sheet Etc. are preferably used.

  As described above, it is important to use a resin black matrix formed of a black resin composition instead of a metal thin film as the black matrix used in the present invention. When the metal thin film is used, the contrast minimum value CRmin of the color filter substrate is small and the contrast value of the liquid crystal display device is small even though the inclination angle θ of the colored layer on the black matrix is sufficiently small. Become.

  As the light-shielding agent used in the resin black matrix of the present invention, black organic pigments, mixed color organic pigments, inorganic pigments and the like can be used. Carbon black, perylene black, aniline black, etc. are used as black organic pigments, and at least two kinds of pigments selected from red, blue, green, purple, yellow, magenta, cyan, etc. are mixed as mixed color organic pigments. Pseudo-blackened inorganic pigments include graphite, fine metal particles such as titanium, copper, iron, manganese, cobalt, chromium, nickel, zinc, calcium, silver, metal oxides, composite oxides, metal sulfides And metal nitrides. These may be used alone or in combination of two or more.

It is preferable to use a light-shielding agent having a high light-shielding property because the resin black matrix layer can be thinned. Titanium compound particles, carbon black, resin-coated carbon black, and the like are preferably used, and titanium compound particles are more preferably used. Here, the titanium compound particles are titanium oxide, titanium nitride, TiN _x O _y (0 <x <2.0, 0...) Expressed by TiO ₂ , Ti _n O _2n-1 (1 ≦ n ≦ 20). 1 <y <2.0) means a material composed of at least one of titanium oxynitride and titanium carbide. Furthermore, titanium nitride having better light shielding properties is preferable.

  In the color filter substrate of the present invention, the thickness of the black matrix layer formed on the transparent substrate is preferably 1.0 μm or less, and more preferably 0.8 μm or less. When the thickness of the black matrix layer is thick, the running height of the colored layer on the black matrix layer is also increased, and the inclination angle θ of the colored layer is increased. As a result, the contrast of the color filter substrate decreases depending on the relative arrangement with the polarizing plate.

  The optical density (optical density, OD value) of the resin black matrix is preferably 3.0 or more in the visible light region with a wavelength of 380 to 700 nm, more preferably 4.0 or more, and further 5.0 or more. Preferably there is. The OD value can be obtained from the following relational expression (2) by measuring using a microspectroscope (MCPD2000 manufactured by Otsuka Electronics).

OD value = log ₁₀ (I ₀ / I) (2)
Here, I _{0 is} incident light intensity, and I is transmitted light intensity.

  Although it does not specifically limit as a colored layer of the color filter substrate of this invention, It forms by the photolithographic method using the colored resin composition which consists of a coloring agent, resin, and a solvent at least.

  Examples of the colorant used in the colored resin composition of the present invention include organic pigments such as red, orange, yellow, green, blue and purple, inorganic pigments and dyes for obtaining desired display characteristics in a liquid crystal display device. Are preferably used. As the pigment used in the pigment dispersion, either an organic pigment or an inorganic pigment can be preferably used, but it is desirable to use an organic pigment in terms of chromaticity characteristics. Of the pigments, those having high transparency and excellent light resistance, heat resistance, and chemical resistance are particularly preferable. When specific examples of typical pigments are indicated by color index (CI) numbers, the following are preferably used, but they are not limited to these.

  Examples of red pigments include Pigment Red (hereinafter abbreviated as PR) 9, PR48, PR97, PR122, PR123, PR144, PR149, PR166, PR168, PR177, PR179, PR180, PR192, PR209, PR215, PR216, PR217, PR220. , PR223, PR224, PR226, PR227, PR228, PR240, PR254, etc. are used.

  Examples of orange pigments include pigment orange (hereinafter abbreviated as PO) 13, PO36, PO38, PO43, PO51, PO55, PO59, PO61, PO64, PO65, PO71, and the like.

  Examples of yellow pigments include pigment yellow (hereinafter abbreviated as PY) PY12, PY13, PY17, PY20, PY24, PY83, PY86, PY93, PY95, PY109, PY110, PY117, PY125, PY129, PY137, PY138, PY139, PY147. , PY148, PY150, PY153, PY154, PY166, PY168, PY185, etc. are used.

Examples of purple pigments include pigment violet (hereinafter abbreviated as PV) 19, PV23, PV29, PV30, PV32, PV37, PV40, and PV50.
Examples of blue pigments include pigment blue (hereinafter abbreviated as PB) 15, PB15: 3, PB15: 4, PB15: 6, PB22, PB60, and PB64.
Examples of green pigments include pigment green (hereinafter abbreviated as PG) 7, PG10, PG36, and PG58.

  In order to make the effect of the present invention remarkable, it is preferable that the contrast of the colored layer alone is high, and in order to improve the contrast of the colored layer, it is preferable to finely disperse the pigment in the colored layer, It is preferable to reduce the diameter of the primary particles of the raw material pigment to be dispersed. As a method for reducing the primary particle size of the pigment, a known method such as salt milling is preferably used. These pigments may be subjected to surface treatment such as rosin treatment, acidic group treatment, basic treatment, etc., if necessary, and a pigment derivative may be added as a dispersant.

  Examples of the resin used in the black resin composition and the colored resin composition of the present invention include photosensitive resins such as epoxy resins, acrylic resins, urethane resins, polyester resins, polyimide resins, polyolefin resins, and gelatin. A material such as a resin or a non-photosensitive resin is preferably used. When non-photosensitive resin is used, after patterning photosensitive resin such as photoresist, pattern processing is performed by removing unnecessary parts, stripping photosensitive resin, and thermosetting in order by photolithography method. It becomes possible.

  The solvent used in the black resin composition and colored resin composition of the present invention is not particularly limited, and water and an organic solvent are used in accordance with the dispersion stability of the pigment to be dispersed and the solubility of the resin to be added. Can do. The organic solvent is not particularly limited, and a (poly) alkylene glycol ether solvent, an aliphatic ester, an aliphatic alcohol, a ketone, an amide polar solvent, or a lactone polar solvent is used. These can be used alone or in combination of two or more. Mixing with other solvents is also preferably used.

  Various additives such as an ultraviolet absorber, a dispersant, and a surfactant may be added to the black resin composition and the colored resin composition of the present invention as necessary. About the photosensitive resin composition Further, a photopolymerization initiator, a polymerizable monomer, etc. are added.

  The black resin composition and the colored resin composition of the present invention can be obtained by dispersing a pigment directly in a resin solution using a disperser, or by dispersing a pigment in water or an organic solvent using a disperser. And then mixed with a resin solution. The method for dispersing the pigment is not particularly limited, and various methods such as a ball mill, a sand grinder, a three-roll mill, and a high speed impact mill can be used, but a bead mill is preferred from the viewpoint of dispersion efficiency and fine dispersion. As the bead mill, a coball mill, a basket mill, a pin mill, a dyno mill, or the like can be used. As the beads of the bead mill, titania beads, zirconia beads, zircon beads and the like are preferably used. The bead diameter used for dispersion is preferably 0.01 mm or more and 5.00 mm or less, more preferably 0.03 mm or more and 1.00 mm or less. When the primary particle diameter of the pigment and the secondary particles formed by agglomeration of the primary particles are small, it is preferable to use fine dispersed beads of 0.03 mm or more and 0.01 mm or less. In this case, it is preferable to disperse using a bead mill having a centrifugal separator capable of separating fine dispersion beads and dispersion. On the other hand, when dispersing a pigment containing coarse particles of about submicron, it is preferable to use dispersed beads of 0.10 mm or more because sufficient pulverization force can be obtained and the pigment can be finely dispersed.

  In the present invention, the method for forming a coating film of the black resin composition on the transparent substrate is not particularly limited. After applying to the entire surface of the substrate by a wet coating method such as spin coating, roll coating, bar coating, or die coating, the openings that do not form the light shielding part are removed by photolithography to form a predetermined light shielding part pattern. Alternatively, the light shielding portion may be formed by a film transfer method, a printing method, an electrodeposition method, or an ink jet method, and the unformed portion may be used as the opening portion. Further, the shape of the opening may be an arbitrary polygonal shape, and may be a rectangular shape, a parallelogram shape, a square shape combining a parallelogram shape, or a zigzag shape. The shape in which a plurality of parallelograms are connected may be a simple connection of the parallelograms, or a so-called “character shape” in which one or two sides of the parallelogram are removed and connected. “Zigzag shape” may be used. Here, the opening shape such as a polygonal shape, a rectangular shape, and a parallelogram shape may be substantially formed in the shape, for example, an additional pattern such as a light shielding portion for shielding the thin film transistor is formed. Also good.

  As a method for forming the colored layer in the present invention, a dyeing method, a pigment dispersion method (photolitho method), a transfer method, a printing method, an electrodeposition method, and the like can be appropriately used. In particular, the pigment dispersion method is preferably used because it enables high-definition pattern processing.

  In the color filter substrate of the present invention, in order to obtain a more remarkable effect, it is preferable to form a transparent resin layer on the colored layer. Conventionally, it has been generally known that a transparent resin layer is formed on a colored layer for the purpose of flattening the surface of the color filter substrate. However, the contrast of the color filter substrate is reduced by forming the transparent resin layer. It has been newly found out that it can be reduced.

  In the color filter substrate of the present invention, the refractive index of the transparent resin layer is preferably in the range of 1.55 to 1.80 in order to obtain a more remarkable effect. Furthermore, the refractive index difference between the colored layer and the transparent resin layer is more preferably in the range of 0.005 to 0.20. The range of the refractive index difference between the colored layer and the transparent resin layer is more preferably 0.005 to 0.10. Japanese Patent Laid-Open No. 11-271526 discloses a technique for reducing the difference in refractive index between a colored layer and a transparent protective film in order to suppress the appearance of interference fringes due to backlight or external light at the interface between the colored layer and the transparent resin layer. ing. In the present invention, as a result of intensive studies to reduce the contrast reduction of the color filter substrate, it has been found that it is effective to reduce the refractive index difference between the colored layer and the transparent resin layer. Here, the refractive index difference between the colored layer and the transparent resin layer is a difference between the average value of the refractive index of each colored layer alone and the refractive index of the transparent resin layer alone.

  The transparent resin layer material used in the present invention is not particularly limited as long as the above-described characteristics can be satisfied. For example, thermosetting resins represented by epoxy resins, acrylic resins and polyimide resins, acrylic resins, and the like Any of the photosensitive resins using and a mixture thereof can be used as appropriate. In addition, an additive may be used to adjust the refractive index of the transparent resin layer, and metal oxide fine particles and metal alkoxide are generally preferably used as the additive. Although disclosed in Japanese Patent No. -271526, it is not particularly limited thereto. Since the colored layer material contains a colored pigment, it has a refractive index generally higher than that of the binder resin alone, and the transparent resin layer material has a higher refractive index than the binder resin used in the colored resin layer material. It is desirable to use a resin material having a high refractive index or to adjust the refractive index to a high level by adding the aforementioned additives.

  In the color filter substrate for a liquid crystal display device of the present invention, a transparent electrode layer may be formed on the colored layer or the transparent resin layer. For the transparent electrode layer, indium / tin oxide (ITO), zinc oxide, tin oxide, or an alloy thereof can be preferably used. As a method for forming the transparent electrode layer, a mask material with a predetermined portion of the display area being opened and a substrate are overlapped, and a desired method using a dipping method, chemical vapor deposition, vacuum deposition method, sputtering method, ion plating method, or the like is used. Can be formed in the region. In particular, in the sputtering method, an electrode with high uniformity can be obtained, and a high film formation rate can be obtained by using DC magnetron sputtering, but the present invention is not limited to these.

The transparent electrode layer may be formed on almost the entire surface without using a mask material, and a photosensitive photoresist is applied to the transparent electrode upper layer formed on the almost entire surface, and etching processing or laser using a photolithography method is applied. It is also possible to form a transparent electrode layer only in a predetermined region by processing. In this case, in order to improve the etching resistance of the color filter substrate, the transparent electrode layer may be formed after the SiO ₂ protective layer is formed.

  In order to maintain the substrate gap between the color filter substrate and the opposite electrode substrate, it is necessary to hold the substrate gap at a predetermined position on either the color filter substrate or the electrode substrate or by providing a columnar spacer on both substrates. However, the formation position of the columnar spacer is not particularly limited, and may be disposed on the light shielding portion so as not to affect the opening, or may be formed on a portion where the light shielding portion and the colored layer are laminated. .

  Although various resin materials can be used as the resin used for the columnar spacer, it is preferable to use either a positive type or a negative type photosensitive resin in consideration of its workability and mechanical strength. For example, as the positive photosensitive resin, a mixture of a novolak resin and a naphthoquinonediadisulfonic acid ester is preferably used. In addition, examples of the negative photosensitive resin include resins such as cyclized rubber-bisazide, phenol resin-azide, acrylic resin, and chemical sensitization. Furthermore, in order to improve the mechanical strength of the columnar spacer, various additives may be added to the resin for adjustment. As the additive, for example, inorganic particles are used. The method for forming the columnar spacer is not particularly limited, but a photolithography method is preferable from the viewpoint of fine processing.

  In the liquid crystal display device of the present invention, the position at which the color filter layer composed of the black matrix layer and the colored layer is formed is not particularly limited, and may be an observer side substrate or an opposing substrate. Good. In addition, a color filter layer may be directly formed on a transparent substrate, or a color filter may be formed on a driving element on which a thin film transistor or the like is formed.

  In the liquid crystal display device of the present invention, a patterned layer may be formed in addition to the color filter layer, and the function, shape, etc. are not particularly limited. For example, it may have various functions, shapes, and the like such as a fixed spacer, a liquid crystal alignment control protrusion, and a gap adjusting transparent resin layer formed in the reflective display region of the transflective liquid crystal display device.

The display mode of the liquid crystal display device is not particularly limited, but an active matrix liquid crystal display device excellent in contrast is preferable, and application to a normally black liquid crystal display device is more preferable. Specific examples include an IPS (in-plane switching) method, an FFS (fringe field switching) method, a VA (vertical alignment) method, a PWA (pin wheel alignment) method, and the like. The VA method may be a so-called MVA (multi-domain VA) method in which alignment control protrusions are formed so as to have a plurality of domains, or a so-called PVA (patterned VA) method in which a transparent electrode is patterned.
Although the example of the present invention is shown below, the embodiment is not particularly limited to this example.

"Contrast of colored resin coating and color filter substrate"
The contrast between the colored resin coating and the color filter substrate is as follows: Luceo polarizing plate “POLAX38S” is used as the polarizing plate, Topcon color luminance meter “BM-5A” is used as the luminance meter, and Dentsu Sangyo Co., Ltd. Measurement was performed with the configuration shown in FIG. 2 using a cathode ray tube light source (15,000 cd / m ² , color temperature 6,900 K). At this time, the polarizing plate 9 was fixed, the polarizing plate 12 was arranged so that the polarizing axis of the polarizing plate 12 was parallel and perpendicular to the polarizing axis of the polarizing plate 9, and the contrast was measured by measuring the luminance.

The depolarization ratio of the linear polarizing plate “POLAX38S” used for the measurement was measured using a spectral radiance meter “SR-UL1” manufactured by Topcon, and the depolarization ratio was 6.93 × 10 ³ at 410 nm.

  For the color filter substrate, the substrate is rotated on the measurement table so that it is 0 to 360 ° with respect to the polarization axis of the polarizing plate 9, and the contrast value at that time is measured by the same method as the colored resin coating film. The maximum contrast value CRmax and the minimum contrast value CRmin were obtained.

"Contrast of LCD"
The luminance in black display and white display was measured using a Topcon color luminance meter “BM-5A” to obtain contrast.

"Specific surface area of micronized pigment"
The specific surface area of the pigment is the adsorption isotherm at a liquid nitrogen temperature (77 K) of N ₂ gas after vacuum degassing at 100 ° C. using a high-precision fully automatic gas adsorption device (“BELSORP” 36) manufactured by Nippon Bell Co., Ltd. The isotherm was analyzed by the BET method to determine the specific surface area.

"Measurement of film thickness"
It measured using the surface level | step difference meter (the Nippon Vacuum Technology company make, FPD-650).

"Measurement of optical density"
It calculated | required from the above-mentioned Formula (2) using the microspectroscope (MCPD2000 by Otsuka Electronics).

"Measurement of coating film refractive index"
The refractive index of the colored layer material and the transparent resin layer material was measured by ellipsometry (ellipsometry) method. Polarization analysis is a method for obtaining a film by irradiating a film surface of a glass substrate with polarized light and reflecting the polarized light on the film surface, and measuring a change in polarization state occurring at this time. A polarization analyzer of AEP-100 manufactured by Shimadzu Corporation was used.

"Measurement of pixel tilt angle"
Cut the color filter substrate, observe the tilted area where the colored layer runs on the black matrix layer with a transmission electron microscope (H-9000UHR, manufactured by Hitachi, Ltd.), and perform image analysis of the photographed photo to tilt the colored layer The angle was determined. In addition, 10 places were observed and analyzed for each colored layer, and all average values were set as the inclination angle θ.

“Calculation of CR reduction rate”
The CR reduction rate was determined by the following formula (3).

    CR reduction rate (%) = (1−CRmin / CRmax) × 100 (3).

Synthesis of polyamic acid 4,4'-diaminophenyl ether (0.30 molar equivalent), paraphenylenediamine (0.65 molar equivalent), bis (3-aminopropyl) tetramethyldisiloxane (0.05 molar equivalent) Charged together with 850 g of γ-butyrolactone and 850 g of N-methyl-2-pyrrolidone, 3,3 ′, 4,4′-oxydiphthalcarboxylic dianhydride (0.9975 molar equivalent) was added, and 3 hours at 80 ° C. Reacted. Maleic anhydride (0.02 molar equivalent) was added and further reacted at 80 ° C. for 1 hour to obtain a polyamic acid A-1 (polymer concentration 20% by weight) solution.
4,4′-diaminophenyl ether (0.95 molar equivalent) and bis (3-aminopropyl) tetramethyldisiloxane (0.05 molar equivalent) were charged together with 1700 g (100%) of γ-butyrolactone, Anhydride (0.49 molar equivalent) and benzophenonetetracarboxylic dianhydride (0.50 molar equivalent) were added and reacted at 80 ° C. for 3 hours. Maleic anhydride (0.02 molar equivalent) was added and further reacted at 80 ° C. for 1 hour to obtain a polyamic acid A-2 (polymer concentration 20% by weight) solution.

Preparation of black resin composition Titanium nitride particles (Sample 1, Wako Pure Chemical Industries, Ltd., “Titanium nitride 50 nm”) (96 g) were added to polyamic acid solution A-1 (120 g), γ-butyrolactone (114 g), N -Methyl-2-pyrrolidone (538 g) and 3-methyl-3-methoxybutyl acetate (132 g) were charged into a tank and stirred for 1 hour with a homomixer (manufactured by Tokushu Kika) to obtain a preliminary dispersion. Thereafter, the pre-dispersed liquid was supplied to an ultra apex mill (manufactured by Kotobuki Industries) equipped with a centrifugal separator filled with 0.05 mmφ zirconia beads (manufactured by Nikkato, YTZ ball) and dispersed for 2 hours at a rotational speed of 8 m / s. And a pigment dispersion Bk-D1 having a solid content concentration of 12% by weight and a pigment / resin (weight ratio) = 80/20 was obtained.

  To this pigment dispersion Bk-D1 (728 g), polyamic acid A-1 (63 g), γ-butyrolactone (82 g), N-methyl-2-pyrrolidone (87 g), 3-methyl-3-methoxybutyl acetate (39 g) ), Surfactant LC951 (manufactured by Enomoto Kasei Co., Ltd., 1 g) was added to obtain a black resin composition Bk1 having a total solid concentration of 10% by weight and a pigment / resin (weight ratio) = 70/30. The OD value of the coating film formed by coating this black resin composition Bk1 on a glass substrate so as to have a film thickness of 1.0 μm was 5.0.

  A black resin composition Bk2 was obtained in the same manner except that titanium oxynitride (Sample 2, manufactured by Mitsubishi Materials Corporation, “13M-C”) was used instead of Sample 1. The OD value of the coating film formed by coating this black resin composition Bk2 on a glass substrate so as to have a film thickness of 1.0 μm was 3.0.

A pigment dispersion Bk-D3 was obtained in the same manner except that carbon black (Sample 3, manufactured by Mitsubishi Chemical Corporation, “MA100”) was used instead of Sample 1.
To this pigment dispersion Bk-D3 (250 g), polyamic acid A-1 (150 g), γ-butyrolactone (134 g), N-methyl-2-pyrrolidone (357 g), 3-methyl-3-methoxybutyl acetate (108 g) ), Surfactant LC951 (manufactured by Enomoto Kasei Co., Ltd., 1 g) was added to obtain a black resin composition Bk3 having a total solid content concentration of 6% by weight and pigment / resin (weight ratio) = 40/60. The OD value of the coating film formed by coating this black resin composition Bk3 on a glass substrate so as to have a film thickness of 1.0 μm was 3.0.

Preparation of Colored Resin Composition “Rionol Green 6YK” (Pigment Green 36, manufactured by Toyo Ink Co., Ltd.) was used as a raw material to perform salt milling by a known method described in JP-A-2005-316244, etc., and a specific surface area of 100 g / m ² A refined green pigment G-P1 was obtained.

Refined yellow having a specific surface area of 90 g / m ² by salt milling using “Pariotol Yellow L09060-HD” (Pigment Yellow 138, manufactured by BASF) as a raw material by a known method described in JP-A-2002-227921 Pigment Y-P1 was obtained.

A refined red pigment having a specific surface area of 100 g / m ² by salt milling using “B-CF” (Pigment Red 254, manufactured by Ciba Specialty) by a known method described in JP-A-2007-31539, etc. R-P1 was obtained.

Refinement with a specific surface area of 110 g / m ² by salt milling using “Lionol Blue 7602” (Pigment Blue 15: 6, manufactured by Toyo Ink Co., Ltd.) as a raw material by a known method described in JP-A-2005-234003 Blue pigment B-P1 was obtained.

  44 g of refined G pigment G-P1, 19 g of refined Y pigment Y-P1, polyamic acid A-2; 47 g, γ-butyrolactone; 890 g were charged in a tank and stirred for 1 hour with a homomixer (manufactured by Tokushu Kika). To obtain a G pigment preliminary dispersion. Thereafter, the pre-dispersion liquid is supplied to Dynomill KDL (manufactured by Shinmaru Enterprises) filled with 85% 0.40 mmφ zirconia beads (manufactured by Toray Industries, Inc., Treceram beads), and dispersed for 3 hours at a rotational speed of 11 m / s. The G dispersion G-D1 having a solid content concentration of 7% by weight and a pigment / polymer (weight ratio) = 90/10 was obtained. The G dispersion G-D1 was diluted with polyamic acid A-2 and γ-butyrolactone to obtain a green resin composition G1 having a pigment / polymer (weight ratio) = 40/60. The contrast of a single coating film formed by coating this green resin composition G1 on a glass substrate so as to have a film thickness of 2.0 μm was 8000, and the refractive index at a wavelength of 540 nm was 1.80.

  A green resin was used in the same manner except that “Lionol Green 6YK” (Pigment Green 36, manufactured by Toyo Ink Co., Ltd.) was used as the green pigment, and “Pariol Yellow L09060-HD” (Pigment Yellow 138, manufactured by BASF) was used as the yellow pigment. Composition G2 was obtained. The contrast of a single coating film formed by coating this green resin composition G2 on a glass substrate so as to have a film thickness of 2.0 μm was 1500, and the refractive index at a wavelength of 540 nm was 1.79.

  70 g of refined G pigment G-P1, 30 g of refined Y pigment Y-P1, 83% by weight (30 wt%) diluted solution (30 wt%) of Ajinomoto Fine Techno “Ajisper” PB821 in propylene glycol monomethyl ether acetate (hereinafter referred to as PGMEA). 3 g, 55.6 g of “Cyclomer” ACA250 (45 wt% solution) manufactured by Daicel Chemical Industries, and 761.1 g of PGMEA were charged in a tank, and stirred for 1 hour with a homomixer (manufactured by Tokushu Kika). Obtained. Thereafter, the pre-dispersion liquid is supplied to Dynomill KDL (manufactured by Shinmaru Enterprises) filled with 85% 0.40 mmφ zirconia beads (manufactured by Toray Industries, Inc., Treceram beads), and dispersed for 3 hours at a rotational speed of 11 m / s. And a G dispersion G-D3 having a solid concentration of 15% by weight was obtained.

  In this G dispersion 72.00g, 6.89g of cyclomer ACA250 (45 wt% solution) as a polymer, 2.10g of "Kayarad" DPHA made by Nippon Kayaku as a reactive monomer, Ciba Specialty as a photopolymerization initiator Chemicals "Irgacure" 907 1.17g, Nippon Kayaku "Kayacure" DETX-S 0.58g as sensitizer, Shin-Etsu Chemical Co., Ltd. KBM1003 0.18g as a surfactant, surfactant 0.40 g of PGMEA diluted solution (10% by weight) of “R-08” manufactured by Dainippon Chemical Industry Co., Ltd. and PGMEA diluted solution (1% by weight) of Wako Pure Chemical Industries, Ltd. DOHQ as a polymerization inhibitor 3.24 g and a mixed solution of 13.45 g of PGMEA as an organic solvent was added, and a photosensitive green resin composition having a solid content concentration of 18% by weight To obtain a G3. The contrast of a single coating film formed by coating this green resin composition G3 on a glass substrate so as to have a film thickness of 2.0 μm was 8200, and the refractive index at a wavelength of 540 nm was 1.63.

  Similarly, instead of the green pigment and the yellow pigment, 63 g of the refined red pigment R-P1 was charged to obtain an R pigment dispersion having a solid content concentration of 7% by weight and a pigment / polymer (weight ratio) of 90/10. Furthermore, it diluted with polyamic acid A-2 and a solvent, and obtained red resin composition R1 of pigment / polymer (weight ratio) = 35/65. The contrast and the refractive index at a wavelength of 610 nm of a single coating film obtained by coating this red resin composition R1 on a glass substrate so as to have a film thickness of 2.0 μm were 4000 and 1.79.

  A red resin composition R2 was obtained in the same manner except that “BT-CF” (Pigment Red 254, manufactured by Ciba Specialty) was used as the red pigment. The contrast of a single coating film formed by coating this red resin composition R2 on a glass substrate so as to have a film thickness of 2.0 μm was 800, and the refractive index at a wavelength of 610 nm was 1.78.

  An R dispersion R-D3 having a solid concentration of 15% by weight was obtained in the same manner as the G dispersion G-D3, except that the refined red pigment R-P1 was used instead of the green pigment and the yellow pigment.

  52.50 g of this R dispersion is 4.40 g of cyclomer ACA250 (45 wt% solution) as a polymer, 3.29 g of “Kayarad” DPHA manufactured by Nippon Kayaku as a reactive monomer, and Ciba Specialty as a photopolymerization initiator. Chemicals "Irgacure" 907 0.88g, Nippon Kayaku "Kayacure" DETX-S 0.44g as sensitizer, Shin-Etsu Chemical KBM1003 0.45g as adhesion improver, surfactant A solution prepared by mixing 0.41 g of “R-08” manufactured by Dainippon Chemical Co., Ltd., 4.88 g of DOHQ as a polymerization inhibitor and 32.76 g of PGMEA as an organic solvent was added. A photosensitive red resin composition R3 was obtained. The contrast of a single coating film formed by coating this red resin composition R3 on a glass substrate so as to have a film thickness of 2.0 μm was 3800, and the refractive index at a wavelength of 610 nm was 1.61.

  Similarly, instead of the red pigment, 63 g of refined blue pigment B-P1 was charged to obtain a B pigment dispersion having a solid content concentration of 7% by weight and a pigment / polymer (weight ratio) = 90/10. Furthermore, it diluted with polyamic acid A-2 and a solvent, and obtained blue resin composition B1 of pigment / polymer (weight ratio) = 30/70. The contrast of a single coating film formed by coating this blue resin composition B1 on a glass substrate so as to have a film thickness of 2.0 μm was 5000, and the refractive index at a wavelength of 430 nm was 1.75.

  A blue resin composition B2 was obtained in the same manner except that “Lionol Blue 7602” (Pigment Blue 15: 6, manufactured by Toyo Ink Co., Ltd.) was used as the blue pigment. The contrast of a single coating film formed by coating this blue resin composition B2 on a glass substrate so as to have a film thickness of 2.0 μm was 1200, and the refractive index at a wavelength of 430 nm was 1.75.

  A B dispersion B-D3 was obtained except that the refined blue pigment B-P1 was used instead of the green pigment and the yellow pigment.

  In 45.00 g of this dispersion B, 8.01 g of cyclomer ACA250 (45 wt% solution) as a polymer, 3.15 g of “Kayarad” DPHA manufactured by Nippon Kayaku as a reactive monomer, and Ciba Specialty as a photopolymerization initiator Chemicals "Irgacure" 907 0.63g, Nippon Kayaku "Kayacure" DETX-S 0.32g as a sensitizer, Shinetsu Chemical Co., Ltd. KBM1003 0.45g as a sensitizer, surfactant 0.41 g of “R-08” manufactured by Dainippon Chemical Industry Co., Ltd., 5.25 g of Wako Pure Chemical Industries, Ltd. DOHQ as a polymerization inhibitor, and 36.77 g of PGMEA as an organic solvent were added and the solution added. The photosensitive blue resin composition B3 was obtained. The contrast of a single coating film formed by coating this blue resin composition B3 on a glass substrate so as to have a film thickness of 2.0 μm was 4900, and the refractive index at a wavelength of 610 nm was 1.62.

Preparation of transparent resin layer material 5 g of Epicoat 827 (bisphenol A type epoxy compound) manufactured by Yuka Shell Epoxy Co., Ltd., 5 g of γ-glycidoxypropylmethyldimethoxysilane, and 5 g of Sb2O5 methanol sol solution having a solid content concentration of 30% , Dissolved in 3-methoxy-3-methylbutyl acetate, and adjusted so that the total solid content concentration was 30%, to obtain a transparent resin material OC1. This transparent resin material OC1 was applied and formed on a glass substrate so as to have a film thickness of 1.0 μm, and the refractive index was measured to be 1.67 at a wavelength of 400 nm.

  44.7 g of 3,3′-diaminodiphenylsulfone, 292.0 g of m-phenylenediamine, and 74.6 g of bis-3- (aminopropyl) tetramethylsiloxane were added to 11497.2 g of N-methylpyrrolidone (NMP) at 30 ° C. And dissolved for 30 minutes. 1747.7 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added to the resulting mixture and heated at 58 ° C. for 3 hours. An NMP solution of polyamic acid was obtained by adding 17.8 g of phthalic anhydride and further heating at 58 ° C. for 1 hour. 5 g of an Sb2O5 methanol sol solution (solid concentration 30%) was added to 5 g of this NMP solution of polyamic acid to obtain a transparent resin material OC2. This transparent resin material OC2 was applied and formed on a glass substrate so as to have a film thickness of 1.0 μm, and the refractive index was measured to be 1.75 at a wavelength of 400 nm.

  After 562.07 g of vinyltrimethoxysilane was dissolved in 700 g of propylene glycol monomethyl ether acetate, 204.89 g of water and 0.05 g of oxalic acid were added. The obtained mixture was heated at 120 ° C. for 2 hours, and water and methanol were distilled off to allow hydrolysis and condensation to proceed. Then, water and methanol were further distilled off with an evaporator. 28 g (30% solid content) of the obtained hydrolysis condensate, 0.46 g of aluminum trisacetylacetonate, 30.2 g of bisphenoxyethanol fluorenediglycidyl ether, 6.7 g of bisoxetane cyclohexanedicarboxylate, and 70. propylene glycol monomethyl ether acetate. 0 g and 1.38 g of acetylacetone were added to obtain a transparent resin material OC3. When this transparent resin material OC3 was applied and formed on a glass substrate so as to have a film thickness of 1.0 μm and the refractive index was measured, it was 1.60 at a wavelength of 400 nm.

  Using an acrylic transparent material (“OPT6917” manufactured by JSR) as the transparent resin material OC4, a film thickness of 1.0 μm was applied and formed on a glass substrate, and the refractive index was measured. there were.

Example 1
[Production of color filter substrate]
The black resin composition Bk1 was coated on a non-alkali glass (Corning “1737 material”) substrate with a curtain flow coater and vacuum-dried at 80 ° C. and 10 ⁻¹ Torr for 2 minutes. Then, semi-cure at 140 ° C. for 20 minutes, apply a positive photoresist (“SRC-100” manufactured by Shipley Co., Ltd.) with a reverse roll coater, pre-bake on a hot plate at 120 ° C. for 5 minutes, and manufactured by Dainippon Screen Co., Ltd. Using an exposure machine “XG-5000”, exposure is performed through a photomask, and development of the positive resist and etching of the polyimide precursor are simultaneously performed using an aqueous tetramethylammonium hydroxide solution. Peeled with sorb acetate. Furthermore, it was cured at 300 ° C. for 30 minutes. Thus, a transparent substrate with a thickness of 1.0 μm, a pixel pitch of 25 μm, a black matrix width of 6 μm, and a stripe-shaped resin black matrix was produced.

  Next, the colored resin composition G1 is applied and processed so that the film thickness becomes 2.0 μm in the same manner to form a green pixel, and then the red pixel is changed to the colored resin composition using the colored resin composition R1. A blue pixel was formed using the object B1. Next, a transparent resin material OC1 was applied and heat-cured as a transparent resin layer so as to have a film thickness of 1.5 μm, and ITO was formed as a transparent electrode to obtain a color filter substrate CF1.

[Production of liquid crystal display devices]
Separately, a substrate in which a TFT element, a pixel electrode, and the like were formed on an alkali-free glass was prepared as a counter substrate. Stripe-shaped protrusions made of polyimide and a fixed spacer having a height of 4 μm were formed on the transparent electrode of each substrate by photolithography, and then a vertical alignment film was provided. The cross section of the protrusion was trapezoidal and the height was about 1.5 μm.

However, the stripe-shaped positions were determined so that the stripe-shaped protrusions were alternately arranged with the opposing stripe protrusions when the color filter substrate CF1 and the glass substrate were bonded together. A sealing agent kneaded with a microrod was printed on one of these two substrates, and the two substrates were bonded together. Next, n-type liquid crystal was filled and sealed between the cells, and a pair of circularly polarizing plates (manufactured by Biei Imaging Co., Ltd.) were arranged so as to be crossed Nicols. In this way, a test liquid crystal display element LCD1 simulating the MVA method was produced.
The color filter substrate CF1 had an average pixel inclination angle θ of 12 °, CRmax of 4700, and CRmin of 3000. Further, the contrast of the liquid crystal display element LCD1 was 1050.

Example 2
A color filter CF2 was prepared in the same manner as in Example 1 except that the thickness of the resin black matrix was changed to 0.6 μm. A liquid crystal display element LCD2 was produced using the color filter substrate 2 in the same manner as in Example 1.
The color filter substrate CF2 had an average pixel inclination angle θ of 9 °, CRmax of 4850, and CRmin of 3400. The contrast of the liquid crystal display element LCD2 was 1200.

Example 3
A color filter substrate CF3 was prepared in the same manner as in Example 1 except that the thickness of the resin black matrix was changed to 0.3 μm. A liquid crystal display element LCD3 was produced using the color filter substrate 3 in the same manner as in Example 1.
The color filter substrate CF3 had an average pixel inclination angle θ of 5 °, CRmax of 4850, and CRmin of 4100. The contrast of the liquid crystal display element LCD3 was 1500.

Comparative Example 1
A color filter substrate CF4 was prepared in the same manner as in Example 1 except that the thickness of the resin black matrix was changed to 1.5 μm. A liquid crystal display element LCD4 was produced using the color filter substrate 4 in the same manner as in Example 1.
The color filter substrate CF4 had an average pixel inclination angle θ of 21 °, CRmax of 4600, and CRmin of 1800. The contrast of the liquid crystal display element LCD4 was 450.

Example 4
A color filter substrate CF5 was prepared in the same manner as in Example 1 except that Bk2 was used as the resin black matrix. A liquid crystal display element LCD5 was prepared in the same manner as in Example 1 using the color filter substrate 5.
The color filter substrate CF5 had an average pixel inclination angle θ of 12 °, CRmax of 4600, and CRmin of 2300. Further, the contrast of the liquid crystal display element LCD5 was 650.

Example 5
A color filter substrate CF6 was prepared in the same manner as in Example 1 except that Bk3 was used as the resin black matrix. A liquid crystal display element LCD6 was produced using the color filter substrate 6 in the same manner as in Example 1.
The color filter substrate CF6 had an average pixel inclination angle θ of 12 °, CRmax of 4700, and CRmin of 2400. Further, the contrast of the liquid crystal display element LCD6 was 700.

Example 6
A color filter substrate CF7 was prepared in the same manner as in Example 1 except that the pixel pitch of the resin black matrix was changed to 50 μm. A liquid crystal display element LCD7 was produced using the color filter substrate 7 in the same manner as in Example 1.
The color filter substrate CF7 had an average pixel inclination angle θ of 12 °, CRmax of 4900, and CRmin of 3600. The contrast of the liquid crystal display element LCD7 was 1350.

Example 7
A color filter substrate CF8 was produced in the same manner as in Example 1 except that the shape of the resin black matrix was changed to a pixel pitch of 25 μm, a pixel long side length of 180 μm, a black matrix width of 6 μm, and a rectangular shape (lattice shape). A liquid crystal display element LCD8 was produced using the color filter substrate 8 in the same manner as in Example 1.
The color filter substrate CF8 had an average pixel inclination angle θ of 12 °, CRmax of 4500, and CRmin of 2600. Further, the contrast of the liquid crystal display element LCD8 was 850.

Example 8
The resin black matrix has a pixel pitch of 25 μm, a pixel long side length of 180 μm, a black matrix width of 6 μm, an upper side and a base side of 60 μm, a height of 90 μm, an angle of 45 °, and either the upper side or the bottom side being open. A color filter substrate CF9 was produced in the same manner as in Example 1 except that the parallelogram thus formed was changed to an opening pattern in which the opened sides were in contact with each other and formed into a square shape. A liquid crystal display element LCD9 was produced using the color filter substrate 9 in the same manner as in Example 1.
The color filter substrate CF9 had an average pixel inclination angle θ of 12 °, CRmax of 4400, and CRmin of 2700. The contrast of the liquid crystal display element LCD9 was 900.

Example 9
A color filter substrate CF10 was prepared in the same manner as in Example 1 except that G2, R2, and B2 were used as the colored resin composition. A liquid crystal display element LCD10 was produced in the same manner as in Example 1 using the color filter substrate 10.
The color filter substrate CF10 had an average pixel inclination angle θ of 12 °, CRmax of 2300, and CRmin of 1700. The contrast of the liquid crystal display element LCD10 was 450.

Comparative Example 2
A color filter substrate CF11 was prepared in the same manner as in Example 1 except that a Cr-deposited metal film was used as the black matrix. A liquid crystal display element LCD11 was produced using the color filter substrate 11 in the same manner as in Example 1.
The color filter substrate CF11 had an average pixel inclination angle θ of 4 °, CRmax of 4800, and CRmin of 1700. The contrast of the liquid crystal display element LCD11 was 400.

Example 10
A color filter substrate CF12 was prepared in the same manner as in Example 1 except that the transparent resin material OC2 was used as the transparent resin layer. A liquid crystal display element LCD 12 was produced using the color filter substrate 12 in the same manner as in Example 1.
The color filter substrate CF12 had an average pixel inclination angle θ of 12 °, CRmax of 4750, and CRmin of 3600. The contrast of the liquid crystal display element LCD12 was 1350.

Example 11
A color filter substrate CF13 was prepared in the same manner as in Example 1 except that the transparent resin material OC3 was used as the transparent resin layer. A liquid crystal display element LCD 13 was produced using the color filter substrate 13 in the same manner as in Example 1.
The color filter substrate CF13 had an average pixel inclination angle θ of 12 °, CRmax of 4700, and CRmin of 2800. Further, the contrast of the liquid crystal display element LCD13 was 950.

Example 12
A color filter substrate CF14 was prepared in the same manner as in Example 1 except that the transparent resin material OC4 was used as the transparent resin layer. A liquid crystal display element LCD 14 was produced in the same manner as in Example 1 using the color filter substrate 14.
The color filter substrate CF14 had an average pixel inclination angle θ of 12 °, CRmax of 4600, and CRmin of 2500. The contrast of the liquid crystal display element LCD14 was 800.

Example 13
A color filter substrate CF15 was prepared in the same manner as in Example 1 except that the transparent resin material OC2 was used as the transparent resin layer. A liquid crystal display element LCD15 was produced using the color filter substrate 15 in the same manner as in Example 1.
The color filter substrate CF15 had an average pixel inclination angle θ of 8 °, CRmax of 4800, and CRmin of 3900. The contrast of the liquid crystal display element LCD15 was 1400.

Example 14
A color filter substrate CF16 was produced in the same manner as in Example 12 except that the transparent resin material OC4 was used as the transparent resin layer. A liquid crystal display element LCD 16 was produced using the color filter substrate 16 in the same manner as in Example 1.
The color filter substrate CF16 had an average pixel inclination angle θ of 8 °, CRmax of 4750, and CRmin of 3300. Further, the contrast of the liquid crystal display element LCD16 was 1150.

Example 15
A color filter substrate CF17 was prepared in the same manner as in Example 2 except that the transparent resin layer was not formed. A liquid crystal display element LCD 17 was produced using the color filter substrate 17 in the same manner as in Example 1.
The color filter substrate CF17 had an average pixel inclination angle θ of 9 °, CRmax of 4500, and CRmin of 2900. The contrast of the liquid crystal display element LCD17 was 1000.

Comparative Example 3
A color filter substrate CF18 was prepared in the same manner as in Example 1 except that the pixel pitch of the resin black matrix was changed to 75 μm and the transparent resin layer was not formed. A liquid crystal display element LCD 18 was produced using the color filter substrate 18 in the same manner as in Example 1.

  The color filter substrate CF18 had an average pixel inclination angle θ of 12 °, CRmax of 4800, and CRmin of 4100. Further, the contrast of the liquid crystal display element LCD18 was 1500.

  Table 1 shows the configurations of the color filter substrates and the liquid crystal display elements prepared in Examples 1 to 15 and Comparative Examples 1 to 3 and the evaluation results thereof. The color filter substrate with a smaller inclination angle θ of the colored layer has a lower CR reduction rate, and the tendency is more remarkable as the pixel pitch is narrower. Furthermore, it turns out that it comprises a transparent resin layer and the reduction rate of CR is smaller as the difference in refractive index between the colored layer and the transparent resin layer is smaller. Further, it can be seen that when the Cr thin film is used as a black matrix, the CRmin value is specifically small and the reduction rate of CR is large although the inclination angle θ of the colored layer is small. It can be seen that the liquid crystal display element using a color filter substrate having a large CRmin value has higher contrast and better display characteristics regardless of the CRmax value.

1: Inclination angle θ of the colored layer
2: Transparent substrate 3: Black matrix layer 4: Colored layer 5: Transparent resin layer 6: Flat part 7: Riding part 8: Luminance meter 9, 12: Polarizing plate 10: Object to be measured 11: Rotating stage 13: Backlight unit

Claims (9)

A liquid crystal compound is filled in a space held by a fixed spacer between a color filter substrate in which a colored pixel made of a colored film is formed in an opening of a black matrix formed on a transparent substrate and a substrate facing the color filter substrate, In a color filter substrate used in a normally black type active matrix liquid crystal display device in which polarizing plates are arranged so that the polarization axes thereof are orthogonal to the surfaces opposite to the surfaces in contact with the liquid crystal compound of both substrates, The black matrix is a resin black matrix composed of at least a resin and a light-shielding agent, wherein the repeating pitch of the colored pixels is 70 μm or less, and the colored film rises from the opening in the inclined area of the colored film that rides on the black matrix An angle of inclination θ of the region with respect to the transparent substrate is 15 ° or less. A filter substrate. Minimal contrast when measured by rotating the color filter substrate from 0 to 360 ° with respect to the polarization axis of a linearly polarizing plate having a depolarization ratio at 410 nm of 5.0 × 10 ³ or more and 5.0 × 10 ⁴ or less 2. The color filter substrate according to claim 1, wherein the value CRmin is 2000 or more. The color filter substrate according to claim 1 or 2, wherein the black matrix layer has a thickness of 1.0 µm or less. The color filter substrate according to claim 1, further comprising a transparent resin layer on the colored layer. The color filter substrate according to claim 4, wherein the refractive index of the transparent resin layer is in a range of 1.55 to 1.80. The color filter substrate according to claim 4 or 5, wherein a difference in refractive index between the colored layer and the transparent resin layer is in a range of 0.005 to 0.20. The color filter substrate according to claim 1, wherein the black matrix contains at least a titanium compound as a light shielding agent. The color filter substrate according to claim 1, wherein the black matrix contains at least titanium nitride as a light shielding agent. A liquid crystal display device comprising the color filter substrate according to claim 1.

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