JP5609207B2 - Method for manufacturing color filter for liquid crystal display device, color filter for liquid crystal display device, and liquid crystal display device - Google Patents

Description

  The present invention relates to a color filter used in a liquid crystal display device.

  In recent years, liquid crystal display devices have been used in various applications such as notebook PCs, personal digital assistants, and digital cameras, taking advantage of characteristics such as light weight, thinness, and low power consumption. Due to the improved display characteristics (brightness, color reproducibility, viewing angle characteristics, etc.) of the liquid crystal display device, the color reproducibility is further improved on the screen for the liquid crystal display device in addition to the conventional notebook PC and desktop monitor. Large LCD TVs, mobile phones that support moving images such as car navigation systems, digital cameras, and 1Seg have been developed.

  A color filter used for colorizing a liquid crystal display device is formed, for example, by forming a black matrix on a transparent substrate and then a colored film of red (R), green (G), and blue (B) on the transparent matrix. A transparent protective film and a transparent electrode are formed as necessary. The black matrix indicates a light shielding region arranged between the colored films and is provided to improve the display contrast of the liquid crystal display device. Conventionally, a black matrix is formed of a finely patterned metal thin film or a resin colored with a light shielding agent.

  When a metal film is used for the black matrix, the reflected light is large, the manufacturing cost is high, and harmful substances such as hexavalent chromium are generated when pattern processing is performed, and environmental pollution becomes a problem. There is. When a multilayer film formed of metal oxide or metal nitride is used, the reflected light is reduced, but the problem of manufacturing cost and environmental pollution is not reduced. On the other hand, in the case of using a resin colored with a light shielding agent, compared with the case of a metal thin film, it is less reflective and generation of harmful substances can be suppressed. However, in order to provide a certain degree of light shielding properties, it is necessary to increase the film thickness several times the film thickness of the metal film.

  When forming a colored film at the opening of the patterned black matrix, the colored film should be formed on the black matrix so that there is no gap at the boundary between the black matrix and the colored film. Generally, as described above, when a resin material is used for the black matrix, the overlapping region between the black matrix and the colored film rises due to the thick film, and there is a problem of deteriorating the surface flatness of the color filter. Recently, wide color reproducibility has been demanded due to high image quality of moving images and the like, and the film thickness of the colored film is becoming larger, and the bulge of the overlapping area between the black matrix and the colored film tends to become larger.

  Moreover, in order to realize wide color reproducibility, a material having high color purity is used, but this tends to reduce the transmittance of the colored film itself. For this reason, in the liquid crystal display device, the brightness is improved by using high intensity backlight light. If high intensity backlight light is used, light leakage may occur at the conventional optical density, so that a higher optical density is required for the black matrix. That is, when a resin material is used for the black matrix, it is necessary to further increase the film thickness, which also causes the surface step of the color filter to be further deteriorated.

  Further, in order to realize high definition of the colored film, it is necessary to make the black matrix finer and thinner. This reduces the pattern area of the black matrix, so that the overlapping area between the black matrix and the colored film is also small. In this area, the black matrix and the colored film do not overlap and a gap is likely to occur at the boundary.

  Problems such as the deterioration of the surface flatness of the color filter and the gap between the black matrix and the colored film are caused by poor alignment of the liquid crystal display panel, poor display due to uneven rubbing, and color reproduction. There is a risk of causing problems such as deterioration of the property and lowering of contrast due to light leakage of the backlight.

  As a method for improving the above problem, as for the surface flatness of the color filter, for example, a method of adjusting the film thickness of the black matrix and the colored film to reduce the level difference between the colored films (see Patent Document 1), or improving the contrast For example, a color filter (see Patent Document 2) using a material obtained by a method of refining a pigment contained in a color material has been proposed. In addition to improving the surface flatness of the color filter, in order to improve the pattern processing accuracy of the black matrix, there is a color filter in which a light-blocking photosensitive resin is laminated on a black matrix formed of a light-blocking non-photosensitive resin. It has been proposed (see Patent Document 3). In a color filter in which a light-shielding photosensitive resin is laminated on a black matrix formed of this light-shielding non-photosensitive resin, the size of the laminated light-shielding photosensitive resin is set to the base non-photosensitive resin. By reducing the size of the black matrix and making the shape of the entire black matrix convex, it is possible to reduce the swell generated in the overlapping region of the black matrix and the colored film.

  However, as described above, the reduction in the level difference of the colored film by adjusting the film thickness of the black matrix or the colored film can be achieved by increasing the thickness of the colored film or the resin black matrix with wide color reproducibility and high optical density. With the color filter structure, it is very difficult to adjust the film thickness so as to reduce the swell of the overlap area between the black matrix and the colored film. As a result of the thinning of the black matrix, the colored layer must be arranged with higher accuracy with respect to the black matrix, and a gap is likely to be formed at the boundary between the black matrix and the colored film. There was a problem that light leakage occurred in the area, and as a result, the contrast was not improved. In addition, for a color filter in which a light-blocking photosensitive resin is laminated on a black matrix formed of a light-blocking non-photosensitive resin, it is necessary to design the optical density characteristics from two layers. There has been a problem that the optical density in the substrate tends to be non-uniform due to variations in the film thickness of the layers. Furthermore, when the size of the laminated light-shielding photosensitive resin is made smaller than the size of the non-photosensitive resin as a base, and the entire shape of the black matrix is formed in a convex shape, the conventional photosensitive resin photolithography is performed. It is necessary to newly provide a coating device and a drying device for laminating a photosensitive resin that was not necessary for processing. In addition, in order to further develop the photosensitive resin after forming the non-photosensitive resin, first, A heating and drying step for thermosetting the non-photosensitive resin is required, and thereafter, a method and an apparatus for enabling development of the thermosetting photosensitive resin are required.

Japanese Patent Publication No. 10-35485 JP 2005-208397 A JP-A-6-331816

  The present invention is intended to solve such problems of the prior art, and provides a liquid crystal display device that uses a resin black matrix to produce a color filter with improved contrast at a low cost, and also has a high display quality. The purpose is to do.

The present invention is achieved by the following color filter manufacturing method in order to provide a color filter with improved surface flatness and contrast at low cost.
(1) A resin black matrix layer and a resist layer which are patterned by forming a non-photosensitive resin black matrix layer on a transparent substrate, applying and drying a photosensitive resist solution thereon, and then performing exposure and development. A method for producing a color filter substrate for a liquid crystal display device, wherein a patterned black matrix is formed by forming a laminated black matrix and then forming red, green and blue colored layers in the openings of the black matrix respectively. Etching of the resin black matrix layer and the photosensitive resist layer so that W1> W2, where W1 is the width of the resist layer formed on the black matrix layer and W2 is the width of the patterned resin black matrix layer A method for producing a color filter for a liquid crystal display device, characterized in that the development is carried out simultaneously.
(2) The method for producing a color filter for a liquid crystal display device according to (1), wherein the photosensitive resist solution contains a positive transparent resin.
(3) Among the red, green, and blue colored layers, the thickness of the colored layer of at least one color is d0, the thickness of the patterned resin black matrix layer is d1, and the patterned resin black matrix layer And d2 <d0 ≦ d2, where d2 is the total film thickness of the resist layers formed thereon, and the liquid crystal display device according to any one of (1) to (2) A method for producing a color filter.
(4) A color filter for a crystal display device, wherein a transparent protective film layer is formed on the surface of the color filter using the production method according to any one of (1) to (3).
(5) A liquid crystal display device comprising a color filter using the production method according to any one of (1) to (4).

  According to the present invention, it is possible to reduce the swell generated in the overlapping region between the black matrix and the colored film and the gap generated at the boundary between the black matrix and the colored film, thereby improving the surface flatness and contrast of the color filter. be able to. In addition, a liquid crystal display device with high display quality can be provided without using new materials and devices.

It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (A) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (B) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (A) It is a schematic surface drawing for demonstrating the color filter for liquid crystal display devices of this invention. (B) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (A) It is a schematic surface drawing for demonstrating the color filter for liquid crystal display devices of this invention. (B) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (A) It is a schematic surface drawing for demonstrating the color filter for liquid crystal display devices of this invention. (B) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention. (A) It is a schematic surface drawing for demonstrating the color filter for liquid crystal display devices of this invention. (B) It is a schematic sectional drawing for demonstrating the color filter for liquid crystal display devices of this invention.

  Hereinafter, the present invention will be described in more detail.

1. Configuration of Color Filter of the Present Invention An example of a schematic sectional view of a color filter for a liquid crystal display device of the present invention is shown in FIG.
In FIG. 1, a color filter is formed by sequentially forming a resin black matrix 2, a photosensitive resist 3, a colored film (red, blue, green) 4, a transparent protective film 5, and a transparent electrode film 6 on a transparent substrate 1. Yes.

  Here, 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 whose surface is coated with silica, organic plastic film Or a sheet | seat etc. are used. As the resin black matrix, a resin black matrix obtained by dispersing a light shielding material in a resin is preferably used. As the resin, polyimide and acrylic are preferable from the viewpoints of heat resistance and chemical resistance. Examples of the black pigment as the light shielding material include Pigment Black 7 and Titanium Black, but are not limited thereto, and various pigments can be used. In addition, you may use the pigment in which surface treatments, such as a rosin process, an acidic group process, a basic group process, are performed as needed.

  Although it does not specifically limit as a photosensitive resist, It is preferable that it is a positive type transparent resin generally used by the photolithographic processing of non-photosensitive resin. Here, the transparent resin specifically means a resin having an average transmittance in the visible light region of 60% or more. Among them, photosensitive resist composed of phenol novolac resin and diazonaphthoquinone compound is widely used in photolithography process to form non-photosensitive resin, and can be applied without introducing new equipment in production. can do. In addition, the material may be a resin used for a color material, for example, a transparent material such as acrylic or polyimide resin.

  The color material is a paste containing a coloring component and a resin component. As the resin component, materials such as a polyimide resin, an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, and a polyolefin resin are preferably used. It is done.

  The transparent protective film may be any material as long as it is a transparent material and has a role as a planarizing layer. As a material for the transparent protective film, an epoxy film, an acrylic epoxy film, an acrylic film, a siloxane polymer film, a polyimide film, a silicon-containing polyimide film, a polyimidesiloxane film, or the like is used. The transparent film as used herein specifically means a resin having an average transmittance in the visible light region of 95% or more.

  As the transparent conductive film, indium tin oxide (ITO), zinc oxide, tin oxide and the like and alloys thereof can be used. The transparent film here means specifically a metal film having an average transmittance in the visible light region of 98% or more.

2. Production method of color filter of the present invention An example of the production method of the color filter used in the present invention is shown below. First, a non-photosensitive resin black matrix is formed on a transparent substrate. As a method for forming the black matrix, a die coating method, a spin coating method, a die spin coating method, a roll coating method, a deping method, or the like is preferably used. Then, heat drying (semi-cure) is performed using an oven or a hot plate. Semi-cure conditions vary depending on the materials used, but it is usually preferable to heat at 60 to 200 ° C. for 1 to 60 minutes. Next, the photosensitive resist material is coated and heat-dried (prebaked) in the same manner as the black matrix, and then exposure and development are performed. As prebaking conditions, heating is usually performed at 70 to 150 ° C. for 1 to 60 minutes. Here, a cross section of the color filter structure after development is shown in FIG. This figure is a cross-sectional view when the colored film is cut in a direction perpendicular to the long side direction of the colored film as viewed from above.

  The shape after development according to the present invention is characterized in that a similarly patterned photosensitive resist 7 is laminated on the patterned black matrix 2, and the width of the resist is larger than the width of the black matrix. . The width of the resist can be easily adjusted by developing conditions. Thereafter, the peeling is usually performed in the step of peeling the photosensitive resist film, but in the present invention, the peeling is not performed, but the heat drying (the present curing) is performed. As for this curing condition, in order to obtain a polyimide resin from a precursor in a black matrix, it is generally heated at 200 to 300 ° C. for 1 to 60 minutes. Here, a cross section of the color filter structure after the main curing is shown in FIG. As shown in FIG. 2B, the laminated resist 3 is formed so as to cover the surface layer of the black matrix 2 by heat melting under the above-described curing conditions as described above. At this time, the width W1 of the resist is larger than the width W2 of the black matrix. The resist width and the black matrix width here refer to respective lengths of a cross section when the colored film is cut in a direction perpendicular to the long side direction of the colored film when viewed from the plane. This means that in the next color film formation, the color material can be filled in the entire opening area of the black matrix when the color film material is applied, and over development of the color film is prevented in the development process. Generation of a gap at the boundary can be prevented. As described above, the black matrix of the present invention and the photosensitive resist can be formed simultaneously by the method of curing the laminated resist 7 after development without peeling.

  Next, a colored film is formed. The formation method is the same as that for the black matrix until the exposure and development steps are performed, and then the photosensitive resist formed on the colored film is peeled off in the peeling step, this cure is performed, and only the colored film is applied to a predetermined area. To form. In the manufacturing method of the present invention, it is possible to give a margin to the development amount of the colored film by the resist covering the surface layer of the black matrix. FIG. 3 shows a cross-sectional view of the color filter structure during color film development. Like FIG. 2, this figure is a cross-sectional view when the colored film is cut in a direction perpendicular to the long side direction of the colored film when viewed from above. For example, when the width L0 of the colored film 4 is smaller than the opening width L1 of the black matrix due to over-development, the color resist flows into the bottom of the multi-layer resist 3 when the color material is applied. It plays a role of blocking development of the colored film, and a gap is not easily generated between the black matrix 2 and the colored film 4. On the other hand, if the width L0 of the colored film 4 may be larger than the opening width L1 of the black matrix, the apparatus is preliminarily overdeveloped by taking advantage of the overdevelopment margin, so that the black It is possible to prevent the protrusion to the other adjacent colored film region side on the matrix 2.

  At this time, the processing accuracy of the colored film can be further improved by designing in advance the thickness of the colored film, the thickness of the black matrix, and the total thickness including the black matrix and the laminated resist. FIG. 4 is a cross-sectional view when the colored film is cut in a direction perpendicular to the long side direction of the colored film when viewed from the plane. In this sectional view, when the thickness of the colored film is d0, the thickness of the black matrix is d1, and the total thickness of the black matrix and the laminated resist is d2, the thickness d0 of the colored film is the thickness of the black matrix. It is preferably larger than d1 and smaller than or equal to the total film thickness d2 of the black matrix and the laminated resist. By designing the film thickness of each layer in advance as described above, it is difficult for gaps to occur at the boundary between the black matrix and the colored film, and also prevents protrusion to the adjacent colored film region side on the black matrix. It becomes possible. By repeating the above process, a plurality of colored films are formed on the substrate.

  Thereafter, if necessary, a transparent protective film is formed by the same method as the colored film. The transparent protective film is preferably formed because it not only protects the surface of the color filter but also has an effect of flattening unevenness such as a step between the colored films. At this time, although the film thickness of the transparent protective film depends on the material, in general, if it is thin, the effect of improving the surface flatness cannot be obtained. Since distortion stress is likely to occur at the interface with the transparent protective film during electrode formation, it is preferably formed in the range of 1 to 2 μm. Next, a transparent electrode is provided by sputtering or vapor deposition, and if necessary, patterned by a photolithography etching method.

  The color filter of the present invention obtained from the above and a liquid crystal display device using the same are used for liquid crystal display screens of personal computers, engineering workstations, navigation systems, liquid crystal televisions, digital cameras, mobile phones, etc. It is also suitably used for projection and the like. Further, in the field of optical communication and optical information processing, it is also suitably used as a spatial modulation element using liquid crystal. A spatial modulation element modulates the intensity, phase, polarization direction, etc. of light incident on the element according to the input signal to the element, and is used for real-time holography, spatial filter, incoherent / coherent conversion, etc. It is.

  Examples of the present invention will be specifically described below, but the present invention is not limited thereto.

(Create black paste for resin black matrix)
3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 4,4′-diaminodiphenyl ether and bis (3-aminopropyl) tetramethyldisiloxane are reacted with N-methyl-2-pyrrolidone as a solvent A polyimide precursor (polyamic acid) solution was obtained. A carbon black mill base having the following composition was uniformly dispersed using a homogenizer, and glass beads were filtered to obtain a black paste.

(Composition of carbon black mill base)
Carbon black (MA100, manufactured by Mitsubishi Kasei Co., Ltd.): 4.6 parts Polyimide precursor solution: 24.0 parts N-methylpyrrolidone: 61.4 parts Glass beads: 90.0 parts.

(Preparation of colored film forming polyimide resin paste)
4,4′-diaminodiphenyl ether, bis (3-aminopropyl) tetramethyldisiloxane, γ-butyrolactone, and N-methyl-2-pyrrolidone were charged at a ratio of 19: 1 to 105: 44, respectively. 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and phthalic anhydride were added in a ratio of 280 to 48 to 1, respectively, to obtain a 25 wt% polyamic acid solution (PAA).

  8: 9 pairs of 4,4'-diaminobenzanilide, 3,3'-diaminodiphenyl sulfone, and bis (3-aminopropyl) tetramethyldisiloxane together with γ-butyrolactone and N-methyl-2-pyrrolidone Charged in a ratio of 1: 134: 27, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and phthalic anhydride were added in a ratio of 1775: 220: 1, respectively, and 20% by weight. A polymer dispersant (PD) which is a polyamic acid solution was obtained.

  Pigment Red PR254, Pigment Yellow PY138, Polymer Dispersant (PD) and γ-butyrolactone, and 3-methoxy-3-methyl-1-butanol together with glass beads, 4: 1 to 23:43 to 20:90, respectively. Then, the glass beads were filtered and removed. In this way, a 5% dispersion of PR254 and PY138 was obtained.

  A solution obtained by diluting the dispersion and polyamic acid solution (PAA) with γ-butyrolactone at a ratio of 9: 3: 8 was added and mixed to obtain a non-photosensitive red color paste. Similarly, a non-photosensitive green paste composed of Pigment Green PG38 and Pigment Yellow PY138 and a non-photosensitive blue paste composed of Pigment Blue PB15: 6 were obtained.

(Preparation of transparent protective film paste)
17. Gamma-aminopropylmethyldiethoxysilane hydrolyzate, methyltrimethoxysilane hydrolyzate and 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride 17 to 5 to 14. Reaction was carried out at a ratio of 5 to obtain a transparent protective film paste.

Example 1
(Design of a color filter with a black matrix layer structure consisting of a resin black matrix and a laminated resist (width of the laminated resist> width of the black matrix))
A plan view of the color filter substrate of Example 1 and a cross-sectional view taken along the line aa ′ are shown in FIGS. 5A and 5B, respectively. As shown in FIG. 5A, the colored film pattern of the resin black matrix 2 is striped, the pitch L2 of the resin black matrix 2 is 50 μm, the width L3 of the resin black matrix 2 is 6 μm, and each color is red, green, and blue. A black matrix having a film width L4 of 44 μm, which is the same as the opening width L1 of the resin black matrix, and a photomask for each colored film were prepared. The development conditions were set so that the width L3 ′ of the laminated resist was 8 μm.

  As shown in FIG. 5B, the film thickness d1 of the resin black matrix is 1.4 μm, the film thickness d0 of each colored film of red, green, and blue is 2.0 μm, and the total film thickness d2 of the resin black matrix and the laminated resist. Is 2.2 μm, the thickness t1 of the transparent protective film is 1.5 μm, and the thickness t2 of the transparent electrode is 1500 angstroms.

(Preparation of a color filter substrate in which the structure of the black matrix layer is a resin black matrix and a multilayer resist (width of the multilayer resist> width of the black matrix))
The black space was coated on an alkali-free glass substrate (manufactured by Corning) with a curtain flow coater and semi-cured with a hot plate to form a resin coating film. Next, a photosensitive resist (manufactured by AZ Co., Ltd.) is applied with a curtain flow coater, pre-baked with a hot plate, exposed through a predetermined photomask with an exposure machine, and then development of the photosensitive resist and etching of the resin coating film are performed. Were performed simultaneously to form a pattern. Next, the resin black matrix was imidized by main curing with a hot plate, and a black matrix and a multilayer resist-formed substrate were produced.

  Next, the polyimide resin red paste was applied onto a resin black matrix substrate with a curtain flow coater and semi-cured with a hot plate to form the red resin coating film. Thereafter, similar to the black paste, a photosensitive resist was applied with a curtain flow coater and pre-baked with a hot plate. Thereafter, using the same exposure machine as in the case of the black paste, after exposure through the photomask designed as described above, development of the photosensitive resist and etching of the resin coating film were simultaneously performed to form a pattern. Next, the resist was peeled off and heated on a hot plate to form a red colored film. The above procedure was repeated to form a green colored film and a blue colored film.

  Next, the transparent protective film paste was applied on a colored film forming substrate with a curtain flow coater and semi-cured with a hot plate to form the coating film. Thereafter, it was dried by heating on a hot plate to form a transparent protective film. Finally, a transparent electrode was sputtered to produce a color filter substrate.

  In order to evaluate the surface flatness of the color filter, as shown in FIG. 5B, the total film thickness d0 ′ of each colored film 4 and the total film thickness T3 of the overlapping region of the black matrix 2 and the colored film 4 are contacted. As a result of measuring each with a film thickness meter (manufactured by Tencor) and subtracting them, a value T4 (absolute value) was obtained.

d0 ′ (red): 3.7 μm, d0 ′ (green): 3.8 μm, d0 ′ (blue): 3.7 μm
T3 (red): 3.7 μm, T3 (green): 3.8 μm, T3 (blue): 3.7 μm
T4 (red): 0.0 μm, T4 (green): 0.0 μm, T4 (blue): 0.0 μm.

  From the above results, the surface level difference T4 of the color filter was as flat as 0.0 μm. Moreover, in order to observe the light leakage from the overlapping area of the black matrix and each colored film, the color filter was observed in the transmission mode of an optical microscope (manufactured by Nikon). As a result, no light leakage was observed in the corresponding portion. Moreover, in order to evaluate the contrast of a color filter, it was 1200 cd as a result of measuring with the contrast measuring device (made by Topcon).

Comparative Example 1
(Design of a color filter whose black matrix layer structure consists only of resin black matrix)
A plan view of the color filter substrate of Comparative Example 1 and a cross-sectional view between bb ′ are shown in FIGS. 6A and 6B, respectively. In FIG. 6A, each of the red, green, and blue colored films is designed so that the colored films are overlapped on the black matrix so that no gap is formed at each boundary between the black matrix 2 and the colored film 4. A photomask for a colored film having a width L4 of 48 μm, which is 4 μm larger than the opening width L1 of the black matrix, was prepared, and a laminated resist was not formed.

(Preparation of color filter substrate with black matrix resin resin matrix only)
The black space was coated on an alkali-free glass substrate (manufactured by Corning) with a curtain flow coater and semi-cured with a hot plate to form a resin coating film. Next, a photosensitive resist (manufactured by AZ Co., Ltd.) is applied with a curtain flow coater, pre-baked with a hot plate, exposed through a predetermined photomask with an exposure machine, and then development of the photosensitive resist and etching of the resin coating film are performed. Were performed simultaneously to form a pattern. Next, the resist was peeled off in a peeling step, and the resin black matrix was imidized by heating with a hot plate to form a black matrix forming substrate.

  Next, red, green and blue colored films, a transparent protective film, and a transparent electrode were sequentially formed in the same manner as in Example 1 to produce a color filter substrate.

  As in Example 1, in order to evaluate the surface flatness of the color filter, as shown in FIG. 6B, the total film thickness d0 ′ of each colored film 4 and the overlapping region of the black matrix 2 and the colored film 4 The total film thickness T3 was measured and the value T4 (absolute value) obtained by subtracting them was determined as follows.

d0 ′ (red): 3.8 μm, d0 ′ (green): 3.8 μm, d0 ′ (blue): 3.8 μm
T3 (red): 4.2 μm, T3 (green): 4.1 μm, T3 (blue): 4.1 μm
T4 (red): 0.4 μm, T4 (green): 0.3 μm, T4 (blue): 0.3 μm.

  From the above results, the surface level difference T4 of the color filter was deteriorated by about 0.3 μm compared to Example 1. Moreover, in order to observe the light leakage from the overlapping area of the black matrix and each colored film, the color filter was observed in the transmission mode of an optical microscope (manufactured by Nikon). As a result, no light leakage was observed in the corresponding portion. As a result of measuring the contrast of the color filter, it was 1100 cd, which was 100 cd lower than that of Example 1.

Comparative Example 2
(Design of a color filter whose black matrix layer structure consists only of resin black matrix)
7A and 7B show a plan view of the color filter substrate and a cross-sectional view taken along line cc ′, respectively. In FIG. 7A, as in Example 1, the pitch L2 of the resin black matrix 2 is 50 μm, the width L3 of the resin black matrix 2 is 6 μm, and the width L4 of each of the red, green, and blue colored films 4 is black. A colored film photomask having the same opening width L1 as that of the matrix of 44 μm was used, no laminated resist was formed, and each film thickness was designed to be the same as in Example 1.

(Preparation of color filter substrate with black matrix structure consisting only of resin black matrix)
A color filter was produced as designed in the same production procedure as Comparative Example 1.

  In order to evaluate the surface flatness of the color filter, as shown in FIG. 7B, the total film thickness d0 ′ of each colored film 4 and the total film thickness T3 of the overlapping region of the black matrix 2 and the colored film 4 are respectively represented. As a result of measuring and subtracting them, a value T4 (absolute value) was obtained.

d0 ′ (red): 3.7 μm, d0 ′ (green): 3.7 μm, d0 ′ (blue): 3.7 μm
T3 (red): 3.6 μm, T3 (green): 3.7 μm, T3 (blue): 3.7 μm
T4 (red): 0.1 μm, T4 (green): 0.0 μm, T4 (blue): 0.1 μm
From the above results, the surface step of the color filter was almost the same as in Example 1, but when the boundary part between the black matrix and each colored film was observed in the transmission mode of an optical microscope (manufactured by Nikon), there was no light in the corresponding part. There was a leak. Due to this light leakage, the contrast of the color filter was 800 cd, which was 400 cd lower than that in Example 1.

Comparative Example 3
(Design of color filter with black matrix layer structure consisting of resin black matrix and multilayer resist (width of multilayer resist <width of black matrix))
FIGS. 8A and 8B are a plan view of the color filter substrate and a cross-sectional view taken along line dd ′, respectively. In FIG. 8A, as in Example 1, the pitch L2 of the resin black matrix 2 is 50 μm, the width L3 of the resin black matrix 2 is 6 μm, and the width L4 of each colored film of red, green, and blue is the resin black matrix. The development conditions were set such that the same black matrix as the opening width L1 of 44 μm and a photomask of each colored film were used, and the width L3 ′ of the laminated resist was 5 μm. Each film thickness was the same as in Example 1.
(Production of a color filter substrate in which the structure of the black matrix layer is a resin black matrix and a laminated resist (width of laminated resist <width of black matrix))
A color filter was produced according to the above-described design by the same production procedure as in Example 1. In order to evaluate the surface flatness of the color filter, as shown in FIG. 8B, the total film thickness d0 ′ of each colored film 4 and the total film thickness T3 of the overlapping region of the black matrix 2 and the colored film 4 are respectively set. As a result of measuring and subtracting them, a value T4 (absolute value) was obtained.

d0 ′ (red): 3.7 μm, d0 ′ (green): 3.7 μm, d0 ′ (blue): 3.7 μm
T3 (red): 3.8 μm, T3 (green): 3.8 μm, T3 (blue): 3.8 μm
T4 (red): 0.1 μm, T4 (green): 0.1 μm, T4 (blue): 0.1 μm.

  From the above results, the surface step of the color filter was about 0.1 μm, and although it was slightly worse than Example 1, a substantially flat result was obtained. When the overlapping area of the black matrix and each colored film was observed, light leakage was observed in the corresponding part. Further, as a result of measuring the contrast of the color filter, it was 780 cd, which was 420 cd lower than that in Example 1.

1: Transparent substrate 1
2: Resin black matrix
3: Photosensitive laminated resist
4: Colored film (red, green, blue)
5: Transparent protective film 6: Transparent electrode film 7, 8: Photosensitive resist

Claims (4)

A non-photosensitive resin black matrix layer was formed on a transparent substrate, and a photosensitive resin solution was applied and dried thereon, followed by exposure and development to form a patterned resin black matrix layer and a resist layer. A method for producing a color filter substrate for a liquid crystal display device, comprising forming a black matrix and then forming red, green, and blue colored layers in the openings of the black matrix, respectively, wherein the patterned resin black matrix layer Etching the resin black matrix layer and developing the photosensitive resist layer so that W1> W2, where W1 is the width of the resist layer formed above and W2 is the width of the patterned resin black matrix layer. A method for producing a color filter for a liquid crystal display device, which is performed simultaneously. The method for producing a color filter for a liquid crystal display device according to claim 1, wherein the photosensitive resist solution contains a positive transparent resin. Method for manufacturing a color liquid crystal display device filter and forming a transparent protective layer to claim 1 or 2 surface of the liquid crystal display device for color filter obtained by the method according to. The liquid crystal display device which comprises the color filter for liquid crystal display devices obtained by the manufacturing method in any one of Claims 1-3 .

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