JP2007010820A - Color filter and liquid crystal display using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter and a liquid crystal display wherein a display defect caused by rubbing and a display defect caused by cell gap unevenness hardly occur. <P>SOLUTION: In the color filter and the liquid crystal display using a resin black matrix and having a spacer as a cell gap controlling means, the black matrix wherein a light shielding agent is dispersed in a resin is provided on a transparent substrate. A recess and a colored layer formed on the peripheral part of the resin black matrix are formed on the periphery of the spacer by providing an opening of the black matrix and overlaps with coloring layers at a part in a resin black matrix region on the periphery of the spacer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a color filter and a liquid crystal display device. In particular, the present invention relates to a liquid crystal display device in which a resin black matrix is formed.

In order to maintain the thickness (cell gap) of the liquid crystal layer, a normal liquid crystal display device generally has plastic beads or glass fibers as a spacer between the color filter substrate and the opposite substrate. The spacer member is dispersed as uniformly as possible by a dry method in which the spacer member is sprayed on the substrate or a wet method in which the spacer member is dispersed and applied in alcohol or chloroform. However, this method has the following problems.
(1) When the liquid crystal penetrates, the spacer member moves and the distribution is biased, causing gap unevenness and causing display unevenness.
(2) Since the position where the spacer is present cannot be controlled, it rides not only on the non-display portion but also on the display portion, thereby degrading the image quality. In particular, when this is used as a light valve of a projection display or as a spatial modulation element, the spacer is enlarged and the image quality is remarkably lowered.
(3) In general, the cell gap is regulated to be constant by the surface tension of the spacer and the liquid crystal and the rigidity of the glass. However, in particular, in a large area of 15 inches or more, the unevenness of the cell gap becomes large, causing display unevenness.

As a method for solving these problems, there is a method of forming a spacer having an appropriate shape on a substrate by a photolithography method (for example, Patent Document 1 and Patent Document 2). However, this method has the following problems.
(4) Impurities adhering to the rubbing roll during rubbing are deposited on the spacers, and the deposited impurities are further scattered in the pixels, causing display defects.
(5) A large force is applied to the spacer during rubbing, the spacer is lost, gap unevenness occurs, and this causes display defects.
(6) Especially in a color filter provided with a flattening layer, the shape of the region serving as the base of the spacer varies due to variations in the flow of the flattening layer, resulting in uneven cell gaps and display defects.

As a method of solving the problems (5) and (6), there is a method of providing an overlap with a colored layer on the resin black matrix at the periphery of the base region of the spacer (for example, Patent Document 3). ) Is not necessarily solved.
JP-A-10-82909 (page 12, FIG. 1) Japanese Patent Laid-Open No. 10-20314 (5th page, FIG. 1) Japanese Patent Laying-Open No. 2003-98531 (page 6, FIG. 5)

  In view of the above problems, the present invention prevents the occurrence of display defects due to rubbing in a color filter and a liquid crystal display device provided with a spacer as a cell gap control means, and the shape variation of a region serving as a base of the spacer It is an object of the present invention to prevent the occurrence of display defects due to the problem.

As a result of earnestly examining the above problems, the present inventors need to fully consider the width of the overlapping region between the resin black matrix region of the base region of the spacer and the colored layer in order to solve the above problem. And the present invention was completed. That is, the color filter and the liquid crystal display device of the present invention have the following configurations.
(1) A resin black matrix in which a light-shielding agent is dispersed in a resin on a transparent substrate, and red, green, and blue on the resin black matrix at the opening of the resin black matrix and at the periphery of the opening In the color filter in which each colored layer is provided and a spacer is provided on the resin black matrix, a region that becomes a recess with respect to the colored layer laminated on the peripheral edge of the opening on the resin black matrix is formed around the spacer. And the bottom width of the recess is 1.5 to 3.0 [mu] m, and the level difference between the bottom of the recess and the top of the colored layer laminated on the peripheral edge of the opening of the resin black matrix is 0.2-2. A color filter characterized by being 0 μm.
(2) The color filter according to (1), wherein the spacer bottom area is 50 to 400 μm ² .
(3) The color filter according to (1) or (2), wherein a flattening layer is provided in at least a part of the display region.
(4) A liquid crystal display device using the color filter according to any one of (1) to (3).

  The color filter of the present invention has a spacer as a cell gap control means and has a function of suppressing defects caused by rubbing. In the liquid crystal display device manufactured using the color filter, impurities generated by rubbing are trapped in the recesses around the spacers, so that display defects due to the impurities are prevented and excellent image quality can be displayed. At the same time, the liquid crystal display device manufactured using the color filter has a cell gap unevenness caused by the missing spacer because the force applied to the spacer during rubbing is relaxed by the convex portions around the spacer to prevent the missing spacer. Display defects can be prevented, and excellent image quality can be displayed. In addition, in the case where the planarizing layer is provided, the convex portions around the spacer serve as weirs, and the flow of the planarizing layer into the foundation region is stabilized and the variation in the foundation region shape is reduced. Display defects due to the generated cell gap unevenness are prevented, and excellent image quality can be displayed.

  Embodiments of the present invention will be described below.

  In the color filter of the present invention, a black matrix layer formed by dispersing a light-shielding agent in a resin is provided on a transparent substrate, and further, each colored layer composed of three primary colors is applied and patterned to form openings and spacers. The substrate is laminated on a part of the black matrix including the peripheral portion of the base region, and a spacer is provided on the base region directly or via a flattening layer and / or a transparent electrode.

  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.

  The resin used for the black matrix layer is not particularly limited, but a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, or a polyolefin resin is preferable. Used. The resin used for the black matrix layer is preferably a resin having higher heat resistance than the resin used for the pixel or the protective film, and is preferably a resin having resistance to an organic solvent used in a process after the resin black matrix is formed. Therefore, a polyimide resin is particularly preferably used.

  Here, the polyimide resin is not particularly limited, but usually a polyimide precursor (n = 1 to 2) mainly composed of a structural unit represented by the following general formula (I) is heated or appropriate. Those imidized with a suitable catalyst are preferably used.

  Further, the polyimide resin may contain bonds other than imide bonds such as amide bonds, sulfone bonds, ether bonds, and carbonyl bonds in addition to imide bonds.

  In the general formula (I), R1 is a trivalent or tetravalent organic group having at least two carbon atoms. From the viewpoint of heat resistance, R1 contains a cyclic hydrocarbon, an aromatic or an aromatic heterocycle, and is preferably a trivalent or tetravalent group having 6 to 30 carbon atoms. Examples of R1 include phenyl group, biphenyl group, terphenyl group, naphthalene group, perylene group, diphenyl ether group, diphenylsulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, cyclobutyl group, cyclopentyl group and the like. It is not limited to these.

  R2 is a divalent organic group having at least 2 carbon atoms. From the viewpoint of heat resistance, R2 contains a cyclic hydrocarbon, an aromatic ring or an aromatic resin ring, and has 6 to 30 carbon atoms. These divalent groups are preferred. Examples of R2 include phenyl group, biphenyl group, terphenyl group, naphthalene group, perylene group, diphenyl ether group, diphenylsulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, diphenylmethane group, cyclohexylmethane group and the like. However, it is not limited to these. In the polymer having the structural unit (I) as a main component, R1 and R2 may each be composed of one of these, or may be a copolymer composed of two or more of each. Furthermore, in order to improve the adhesion to the substrate, it is preferable to copolymerize bis (3-aminopropyl) tetramethyldisiloxane having a siloxane structure as a diamine component within a range that does not lower the heat resistance.

  Specific examples of the polymer having the structural unit (I) as a main component include pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4, The group consisting of 4′-biphenyltrifluoropropanetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfonetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, and the like One or more carboxylic dianhydrides selected from the group consisting of paraphenylenediamine, 3,3'-diaminophenyl ether, 4,4'-diaminophenyl ether, 3,4'-diaminophenyl ether, 3,3'- Diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 4,4′-diaminodicyclohexylmethane, 4,4′-diaminodiphenylmethane, etc. However, it is not limited to these. These polyimide precursors are synthesized by a known method, that is, by selectively combining tetracarboxylic dianhydride and diamine and reacting them in a solvent.

  As a light-blocking agent for resin black matrix, a mixture of metal oxide powder such as carbon black, titanium oxynitride, titanium oxide and iron tetroxide, metal sulfide powder and metal powder, as well as a mixture of red, blue and green pigments Etc. can be used. Among these, carbon black and titanium oxynitride are particularly preferable because of their excellent light shielding properties. In order to adjust the chromaticity and the like, it is preferable to mix a pigment with the light-shielding agent to make an achromatic color.

  When the black matrix resin is polyimide, the black paste solvent is usually an amide polar solvent such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, γ-butyrolactone, etc. The lactone polar solvent is preferably used.

  Examples of the method for dispersing the light-shielding agent and other pigments with respect to the light-shielding agent include, for example, mixing a light-shielding agent or a dispersant in the polyimide precursor solution, and then, for example, three rolls, a sand grinder, or a ball mill. Although there is a method of dispersing in a disperser, it is not particularly limited to this method. Various additives may be added to improve the dispersibility of the light-shielding agent or to improve the coating property and leveling property.

  As a method for forming the resin black matrix, patterning is performed after a black paste is applied on a transparent substrate and dried. As a method for applying the black paste, a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, and the like are preferably used. Thereafter, heat drying (semi-cure) is performed using an oven or a hot plate. Do. Semi-cure conditions vary depending on the resin, solvent, and paste application amount to be used, but it is usually preferable to heat at 50 to 200 ° C. for 1 to 60 minutes.

  The black paste film is formed by the above method using a paste using a photosensitive or non-photosensitive resin. When the resin is a non-photosensitive resin, after forming a positive type photoresist film thereon, and when the resin is a photosensitive resin, as it is or after forming an oxygen blocking film, Perform exposure and development. If necessary, the positive photoresist or the oxygen blocking film is removed and heat-dried (main cure). In the case of obtaining a polyimide resin from a precursor, the present curing conditions are generally slightly increased depending on the coating amount, but are generally heated at 200 to 350 ° C. for 1 to 60 minutes. Through the above process, a resin black matrix is formed on the transparent substrate.

  The film thickness of the resin black matrix is preferably 0.5 to 2.0 μm, more preferably 0.7 to 1.5 μm. When this film thickness is thinner than 0.5 μm, it is not preferable because the light shielding property becomes insufficient.

  Openings are provided between the resin black matrices, and a plurality of colored layers of the three primary colors are arranged so as to cover at least the openings. That is, one opening is covered with any one colored layer of the three primary colors, and a plurality of colored layers of each color are arranged.

  The colored layer constituting the color filter includes at least three primary colors. That is, when performing color display by the additive color method, three primary colors of red (R), green (G), and blue (B) are selected. In general, an element including these three primary colors can be used as a unit as a color display picture element. For the colored layer, a resin colored with a colorant is used.

  As the colorant used in the colored layer, organic pigments, inorganic pigments, dyes and the like can be suitably used, and various additives such as ultraviolet absorbers, dispersants, and leveling agents may be added. . As the organic pigment, phthalocyanine, azirake, condensed azo, quinacridone, anthraquinone, perylene, and perinone are preferably used.

  As the resin used for the colored layer, a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, or a polyolefin resin is preferably used. It is preferable to disperse or dissolve in these resins for coloring. Photosensitive resins include photodegradable resins, photocrosslinkable resins, photopolymerizable resins, and the like, and in particular, monomers, oligomers or polymers having an ethylenically unsaturated bond and an initiator that generates radicals by ultraviolet rays. A photosensitive composition, a photosensitive polyamic acid composition, and the like are preferably used. As the non-photosensitive resin, those that can be developed with the above-mentioned various polymers are preferably used. However, the non-photosensitive resin has heat resistance that can withstand the heat applied in the transparent conductive film forming process and the liquid crystal display manufacturing process. A resin having a property is preferable, and a resin having resistance to an organic solvent used in a manufacturing process of a liquid crystal display device is preferable, and a polyimide resin is particularly preferably used. Here, as a preferable polyimide resin, a polyimide resin preferably used as a material of the above-described resin black matrix can be exemplified.

  As a method for forming a colored layer, patterning is performed after coating and drying on a substrate on which a resin black matrix is formed. As a method of dispersing or dissolving a colorant to obtain a colored paste, after mixing a resin and a colorant in a solvent, there is a method of dispersing in a disperser such as a triple roll, sand grinder, ball mill, etc. The method is not particularly limited.

  As a method for applying the colored paste, as in the case of the black paste, a dip method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, etc. are preferably used, and then an oven or a hot plate is used. Heat drying (semi-cure). Semi-cure conditions vary depending on the resin, solvent, and paste application amount to be used, but it is usually preferable to heat at 60 to 200 ° C. for 1 to 60 minutes.

  When the resin is a non-photosensitive resin, the colored paste film thus obtained is formed after a positive photoresist film is formed thereon, and when the resin is a photosensitive resin. As it is or after forming an oxygen blocking film, exposure and development are performed. If necessary, the positive photoresist or the oxygen blocking film is removed and heat-dried (main cure). Although this curing condition changes with resin, when obtaining polyimide-type resin from a precursor, although it changes a little with coating amounts, it is common to heat at 200-300 degreeC normally for 1 to 60 minutes. Through the above process, a patterned colored layer is formed on the substrate on which the black matrix is formed.

  After the first colored layer is formed over the entire surface of the substrate on which the black matrix is formed as described above, unnecessary portions are removed by photolithography to form a desired colored layer pattern of the first color. . In this case, a part that covers at least the opening of the black matrix and a part of the black matrix, that is, a part that leaves the colored layer on the periphery of the opening of the black matrix are formed. At this time, a colored layer portion in which the concave portion and the peripheral edge portion of the opening portion of the black matrix are stacked is formed around a portion where the spacer is formed on the black matrix in a later step.

  A planarizing layer (transparent protective film, overcoat) can be formed on the colored layer as necessary. As the resin used for the planarization layer, an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, a polyolefin resin, gelatin, and the like are preferably used. Resin having heat resistance that can withstand the heat applied in the manufacturing process of the liquid crystal display device is preferable, and resin having resistance to the organic solvent used in the manufacturing device of the liquid crystal display device is preferable. Resins, acrylic resins, and epoxy resins are preferably used.

  As a method for applying the flattening layer, a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, and the like are preferably used as in the case of a black paste and a colored paste. Heat drying using a hot plate. At this time, for the purpose of improving the leveling property, vacuum drying or preheating drying (semi-cure) may be performed as necessary. Semi-cure conditions vary depending on the resin, solvent, and paste application amount to be used, but it is usually preferable to heat at 60 to 200 ° C. for 1 to 60 minutes. Moreover, although the curing conditions at the time of heat drying (this curing) differ a little with resin and the application quantity, it is common to heat at 200-300 degreeC normally for 1 to 60 minutes.

  The film thickness of the planarizing layer is preferably formed so that the step between the top of the convex part and the bottom of the concave part is 0.2 to 2.0 μm, and is 0.3 to 1.5 μm. It is more preferable to form them as follows. If the level difference is smaller than 0.2 μm, impurities generated by rubbing are not easily trapped in the concave portion, so that a display defect is likely to occur and the effect of the convex portion on reducing the force applied to the spacer during rubbing is also small. This is not preferable because the spacer is easily lost and cell gap unevenness is likely to occur. In addition, if the level difference is larger than 2.0 μm, the flow when the spacer material is applied is not stable, the spacer height varies, and cell gap unevenness is likely to occur, which is not preferable.

  If necessary, a transparent conductive film is further formed. Although there is no restriction | limiting in particular as a material of an electrically conductive film, The material excellent in transparency is used preferably, Especially preferably, ITO is used.

  There is no particular limitation on the film forming method, and the vacuum deposition method, CVD method, sputtering method, EB method, dipping method, roll coater method, as in the case of black paste or the like in which conductive fine particles are dispersed in a resin such as polyimide. A spinner method, a die coating method, a method of applying and heating with a wire bar, and the like are preferably used.

  As the resin used for forming the spacer, a resin having a photosensitive property or a non-photosensitive resin may be used.

  As the photosensitive resin, either positive type or negative type photosensitive resin may be used, but it can be selected in consideration of required mechanical strength and the like.

  The positive resist is not particularly limited, but a mixture of a novolak resin and a naphthoquinone didisulfonic acid ester is preferably used.

  Examples of the negative resist include cyclized rubber-bisazide, phenol resin-azide, acrylic resin, chemical sensitization, and the like. For example, in the case of acrylic resin, an oligomer having a molecular weight of 1000 to 2000 is preferably used. Acrylate or epoxy acrylate such as phenol novolac epoxy acrylate, o-cresol novolac epoxy acrylate, polyurethane acrylate, polyether acrylate, oligomer acrylate, alkyd acrylate, melamine acrylate, etc., and polyfunctional photopolymerizable acrylate Monomers include 1,4-butanediol diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, pentae Sri tall triacrylate, trimethylolpropane triacrylate, pentaerythritol acrylate, dipentaerythritol hexaacrylate.

  Furthermore, when the target mechanical properties cannot be satisfied with the above-described resin alone, various additives may be added to the resin for adjustment. As the additive, for example, in inorganic particles, extender pigments such as silica, barium sulfate, barium carbonate, calcium carbonate, talc, and colored pigments such as black, red, blue, green, and alumina, zirconia, magnesia, beryllia, Ceramic powders such as mullite and cordierite, and glass-ceramic composite powders are used. Of the extender pigments, barite, barium sulfate, calcium carbonate, silica and talc are preferable.

  As a method of forming the spacer, for example, there is a method of performing patterning after applying and drying a resin on a substrate. As a method for applying the resin, as with the colored layer, there are a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, etc., but from the point of forming a uniform height, die coating The method is preferred. Thereafter, vacuum drying may be performed and further heating may be performed using an oven or a hot plate.

  The spacer thus obtained is then exposed and developed and heated again. At this time, the exposure amount varies depending on the film thickness of the resin, the spacer bottom area, and the like.

In the case of a positive photoresist, the exposure dose is preferably 60 to 300 mJ / cm ² , more preferably 80 to 160 mJ / cm ² . Further, the developer concentration varies depending on the shape, height and area of the spacer, but is preferably 0.5 to 3%, more preferably 1 to 2.5%, and still more preferably 2 to 2.4%.

For negative photoresist, the exposure dose is preferably more preferably 60~500mJ / cm ² is 100~300mJ / cm ^2. The developer concentration is preferably 0.05 to 3%, more preferably 0.1 to 1%.

  After that, it is reheated in an oven or a hot plate to complete the curing. The reheating temperature may be appropriately selected according to the type of resin to be used. For example, when a polyimide resin is used, it is preferably in the range of 180 to 300 ° C, more preferably in the range of 250 to 290 ° C. is there. When acrylic resin is used, it is preferably in the range of 180 to 290 ° C, more preferably in the range of 220 to 250 ° C.

  Although it does not specifically limit as resin to be used, Materials, such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, and a polyolefin resin, are used preferably.

  Furthermore, when the target mechanical properties cannot be satisfied with the above-described resin alone, various additives may be added to the resin for adjustment. As the additive, for example, in inorganic particles, extender pigments such as silica, barium sulfate, barium carbonate, calcium carbonate, talc, and colored pigments such as black, red, blue, green, and alumina, zirconia, magnesia, beryllia, Ceramic powders such as mullite and cordierite, and glass-ceramic composite powders are used. Of the extender pigments, barite, barium sulfate, calcium carbonate, silica and talc are preferable.

  As a method for forming a spacer using a non-photosensitive resin, for example, there is a method of performing patterning after applying and drying a resin on a substrate. As a method for applying the resin, as with the colored layer, there are a dipping method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, etc., but from the point of forming a uniform height, die coating The method is preferred. Thereafter, vacuum drying may be performed and further heating may be performed using an oven or a hot plate.

  The non-photosensitive resin film thus obtained is exposed and developed after a positive photoresist film is formed thereon. If necessary, the positive photoresist is removed and heat-dried (main cure). Although this curing condition changes with resin, when obtaining polyimide-type resin from a precursor, although it changes a little with coating amounts, it is common to heat at 200-300 degreeC normally for 1 to 60 minutes.

  The shape of the spacer is not particularly limited, and is appropriately selected from a circle, an ellipse, an oval system, a square, a rectangle, a triangle, and other polygons.

The spacer bottom area varies depending on the panel design and panel manufacturing conditions, but is preferably 50 to 400 μm ² . If the spacer is circular, the bottom area is more preferably 50 to 300 μm ² , further preferably 50 to ²⁰⁰ μm ² . More preferably the bottom area 60～400Myuemu ² if the spacer is square, more preferably 60~250μm ^2. If the area is smaller than 50 μm ² , the spacer is liable to be crushed and cell gap unevenness is liable to occur. When the area is larger than 400 μm ² , the contact with the spacer of the rubbing roll becomes excessive, and the spacer tends to fall off, which is not preferable.

  The height of the spacer, that is, the distance from the bottom of the spacer to the apex is not particularly limited. The appropriate height varies depending on the panel design and panel manufacturing conditions, but is preferably 0.5 to 5.0 μm.

  1.5-3.0 micrometers is preferable and, as for the bottom part width | variety of the recessed part formed in a spacer peripheral part, 2.0-2.5 micrometers is more preferable.

  The “bottom width of the recess” as used in the present invention refers to the top of the colored layer formed on the periphery of the resin black matrix around the spacer from an arbitrary point on the outermost periphery of the bottom surface of the spacer when the spacer is formed. The shortest horizontal distance to the edge. If the bottom width of the recess is smaller than 1.5 μm, the flow when the spacer material is applied is not stable, the spacer height varies, and cell gap unevenness is likely to occur, which is not preferable. Also, if the bottom width of the concave portion is larger than 3.0 μm, the concave portion is too wide and impurities generated by rubbing are difficult to be trapped in the concave portion. Further, the effect of alleviating the force applied to the spacer during rubbing at the top of the colored layer is reduced, so that the spacer is easily lost and cell gap unevenness is likely to occur, which is not preferable. The same operation is repeated for the second color and the third color to form a colored layer.

  Further, the bottom portion in the concave portion refers to the lowest portion in the concave portion surrounded by the spacer on the resin black matrix and the colored layer laminated on the resin black matrix or the overcoat layer formed thereon, for example, In FIG. 5, the black matrix is exposed, and in FIG. 6, the lowest portion of the overcoat portion around the spacer is shown.

  It is preferable that the planar shape of the recess is substantially similar to the planar shape of the spacer when viewed from the upper surface of the color filter. That is, it is preferable that the bottom width of the recess is substantially equal at any point on the bottom surface of the spacer. Moreover, the colored layer which forms the top part of the colored layer formed in the resin black matrix peripheral part can be selected suitably by the position where a spacer is arrange | positioned. Based on FIG. 1, FIG. 2, FIG. 3, and FIG. 4, the shape of the concave portion and the shape of the spacer, and the colored layer and the spacer forming the top of the colored layer formed on the peripheral portion of the resin black matrix are arranged. The position will be described. The color filter shown in FIGS. 1 to 4 is provided on the opening of the resin black matrix 24 and on a part of the resin black matrix 24 after the resin black matrix 24 shown in FIG. 13 is formed on the transparent substrate 22. The colored layer 26 and the spacer 30 are formed, and the concave portion 40 and the top 41 of the colored layer formed on the peripheral portion of the resin black matrix are formed around the spacer 30. As shown in FIG. 1, when the circular spacer 30 is formed at the intersection of the resin black matrix 24 formed vertically and horizontally, the top portion 41 of the colored layer formed at the peripheral portion of the resin black matrix has two colored layers 26A and 26B. Thus, the recess 40 is formed in a circular shape. As shown in FIG. 2, when a circular spacer is formed in addition to the intersection, the top portion 41 of the colored layer formed on the peripheral portion of the resin black matrix is formed so that the concave portion 40 is circular with only one colored layer 26A. It is formed. As shown in FIG. 3, when the square spacer 30 is formed at the intersection of the resin black matrix 24 formed vertically and horizontally, the top 41 of the colored layer formed at the peripheral edge of the resin black matrix has two colored layers 26A and 26B. Thus, the recess 40 is formed in a square shape. As shown in FIG. 4, when a square spacer is formed in addition to the intersection, the top portion 41 of the colored layer formed on the peripheral portion of the resin black matrix is formed so that the concave portion 40 becomes a square shape by only one colored layer 26A. It is formed.

  The film thicknesses of the three primary colors are preferably formed such that the step between the top of the colored layer formed on the peripheral edge of the resin black matrix and the bottom of the recess is 0.2 to 2.0 μm. More preferably, the thickness is 0.3 to 1.5 μm. If the level difference is less than 0.2 μm, impurities generated by rubbing are not easily trapped in the recesses, so that display defects are likely to occur, and the top of the colored layer formed on the periphery of the resin black matrix is a spacer during rubbing. The effect of alleviating the force applied to the film becomes small, so that the spacer is easily lost and cell gap unevenness is likely to occur. In addition, if the level difference is larger than 2.0 μm, the flow when the spacer material is applied is not stable, the spacer height varies, and cell gap unevenness is likely to occur, which is not preferable.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on a preferable Example, the efficacy of this invention is not restrict | limited at all by the following Example.

Example 1
(Create resin black matrix)
3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 4,4′-diaminodiphenyl ether, and bis (3-aminopropyl) tetramethyldisiloxane in N-methyl-2-pyrrolidone as a solvent It was made to react and the polyimide precursor (polyamic acid) solution was obtained.

  A carbon black mill base having the composition shown in Table 1 was dispersed with a homogenizer at 7000 rpm for 30 minutes, and the glass beads were filtered to prepare a black paste.

The black paste was applied to a glass substrate (Corning, 1737 material) with a curtain flow coater and dried on a hot plate at 140 ° C. for 10 minutes to form a black resin coating film. A positive photoresist (manufactured by Clariant, AZ RFP250SA) was applied with a curtain flow coater, pre-baked on a hot plate at 110 ° C. for 5 minutes, exposed to 120 mJ / cm ² ultraviolet rays using an ultra-high pressure mercury lamp, and exposed to mask 2 Using a 25% aqueous solution of tetramethylammonium hydroxide, simultaneously develop the photoresist and etch the resin coating to form a pattern, strip the resist with methyl cellosolve acetate, and heat at 290 ° C. for 10 minutes on a hot plate This was imidized to form a black matrix layer.

At this time, the film thickness of the resin black matrix layer was 1.25 μm.
(Formation of colored layer)
Next, as red, green and blue pigments, dianthraquinone pigment represented by Color index No. 65300 Pigment Red 177, phthalocyanine green pigment represented by Color index No. 74265 Pigment Green 36, Color index No. 74160 Pigment A phthalocyanine blue pigment represented by Blue 15-4 was prepared. The above pigments were mixed and dispersed in the polyimide precursor solution to obtain three types of colored pastes of red, green and blue.

Next, a red paste was applied on the substrate on which the resin black matrix was formed with a curtain flow coater, and dried on a hot plate at 120 ° C. for 10 minutes to form a red resin coating film. Thereafter, a positive type photoresist (manufactured by Clariant, AZ RFP250SA) was applied with a curtain flow coater, pre-baked with a hot plate at 120 ° C. for 5 minutes, and exposed to a mask with 120 mJ / cm ² UV irradiation using an ultra-high pressure mercury lamp. Thereafter, using a 2.25% aqueous solution of tetramethylammonium hydroxide, development of the photoresist and etching of the resin coating were simultaneously performed to form a pattern, the resist was stripped with methyl cellosolve acetate, and 280 ° C., 10 ° C. with a hot plate. It was made to imidize by heating for a part, and the red colored layer was formed.

  In the same manner after washing with water, a green paste was applied to a substrate on which a resin black matrix and a red colored layer were formed, and patterned to form a green colored layer.

  Further, after washing with water, a blue paste was applied to a substrate on which a resin black matrix, red and green colored layers were formed, and patterned to form a blue colored layer.

  At this time, the red, green, and blue colored layers were patterned so that the colored layers were not formed at the positions where the spacers were formed.

The film thicknesses of the red, green, and blue colored layers were each 1.5 μm.
(Formation of transparent conductive film)
After washing with water, an ITO film was then formed as a mask by sputtering.

At this time, the thickness of the ITO film was 140 nm and the surface resistance was 20Ω / □.
(Spacer formation)
Further, after washing with water, photosensitive acrylic resin Optoma NN-810 (manufactured by JSR) was applied with a curtain flow coater, and vacuum drying was performed while heating at 80 ° C. Furthermore, after performing mask exposure by irradiating 300 mJ / cm ² ultraviolet rays using a high-pressure mercury lamp, developing using a 0.3% tetramethylammonium hydroxide aqueous solution, heating on a hot plate at 240 ° C. for 10 minutes. The reaction was completed and a circular spacer was formed.

  At this time, the height of the spacer was 1.5 μm. The bottom width of the concave portion around the spacer was 2 μm, and the step between the top of the colored layer formed on the peripheral edge of the resin black matrix and the bottom of the concave portion was 1.4 μm. The spacer bottom area was 80 μm 2.

Thus, a color filter having the structure shown in the schematic diagram of FIG. 5 was obtained.
(Production and evaluation of liquid crystal display devices)
A polyimide-based alignment film was provided on the obtained color filter and rubbed. Similarly, a polyimide alignment film was provided on the opposing liquid crystal display element substrate, and a rubbing treatment was performed. A sealant was applied and bonded to the two substrates so as to cover the resin black matrix. Next, after injecting liquid crystal from the injection port provided in the seal portion, the injection port was sealed, and a polarizing plate was bonded to the outside of the substrate to produce a liquid crystal display device. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, no display failure due to rubbing occurred, and the cell gap variation was also good.

Example 2
After forming a resin black matrix and a colored layer in the same manner as in Example 1, an acrylic resin solution was applied with a curtain flow coater and heated on a hot plate at 260 ° C. for 10 minutes to form a planarization layer.

  At this time, it was 1.5 micrometers when the film thickness of the planarization layer on raw glass was measured.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the level difference between the top of the colored layer and the bottom of the recess formed on the periphery of the resin black matrix around the spacer was 0.3 μm. The bottom width of the recess around the spacer was 2 μm. The spacer bottom area was 80 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 6 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, there was almost no display failure due to rubbing, and the cell gap variation was also good.

Comparative Example 1
After forming a resin black matrix in the same manner as in Example 1, a colored layer was formed using a photomask different from that in Example 1.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the bottom width of the concave portion around the spacer was 0.5 μm, and the level difference between the top of the colored layer formed on the peripheral portion of the resin black matrix and the bottom of the concave portion was 1.4 μm. The spacer bottom area was 80 μm ² .

  As a result, a color filter having the structure shown in the schematic diagram of FIG. 7 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, there was almost no display failure due to rubbing, but since the flow of the spacer material was not stable, the cell gap variation was large.

Comparative Example 2
A resin black matrix and a colored layer were formed in the same manner as in Comparative Example 1, and then a planarizing layer was formed in the same manner as in Example 2.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the level difference between the top of the colored layer and the bottom of the recess formed on the periphery of the resin black matrix around the spacer was 0.3 μm. The bottom width of the recess around the spacer was 0.5 μm. The spacer bottom area was 80 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 8 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, there was almost no display failure due to rubbing, but since the flow of the spacer material was not stable, the cell gap variation was large.

Comparative Example 3
After forming a resin black matrix in the same manner as in Example 1, a colored layer was formed using a photomask different from that in Example 1.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the width of the bottom of the recess around the spacer was 3.5 μm, and the step between the top of the colored layer formed on the periphery of the resin black matrix and the bottom of the recess was 1.4 μm. The spacer bottom area was 80 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 9 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, the cell gap variation was good, but since the impurities generated by rubbing could not be sufficiently trapped, display defects due to rubbing frequently occurred.

Comparative Example 4
A resin black matrix and a colored layer were formed in the same manner as in Comparative Example 3, and then a planarizing layer was formed in the same manner as in Example 2.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the level difference between the top of the colored layer and the bottom of the recess formed on the periphery of the resin black matrix around the spacer was 0.3 μm. The bottom width of the recess around the spacer was 3.5 μm. The spacer bottom area was 80 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 10 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, the cell gap variation was good, but since the impurities generated by rubbing could not be sufficiently trapped, display defects due to rubbing frequently occurred.

Comparative Example 5
After forming the resin black matrix in the same manner as in Example 1, the colored layer was formed by making the colored layer thicker than in Example 1. At this time, the film thickness of each of the red, green, and blue colored layers was 2.6 μm.

After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the width of the bottom of the recess around the spacer was 2 μm, and the step between the top of the colored layer formed on the periphery of the resin black matrix and the bottom of the recess was 2.5 μm. The spacer bottom area was 80 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 11 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, there was almost no display failure due to rubbing, but since the flow of the spacer material was not stable, the cell gap variation was large.

Comparative Example 6
After forming a resin black matrix in the same manner as in Example 1, the colored layer was made thinner than in Example 1 to create a colored layer. At this time, the film thickness of each of the red, green, and blue colored layers was 1.0 μm. Thereafter, a planarizing layer was formed in the same manner as in Example 2.

  After the formation of the transparent conductive film, the same procedure as in Example 1 was performed. At this time, the level difference between the top of the colored layer and the bottom of the recess formed on the periphery of the resin black matrix around the spacer was 0.1 μm. The bottom width of the recess around the spacer was 2 μm. The spacer bottom area was 80 μm 2.

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 12 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, the cell gap variation was good, but since the impurities generated by rubbing could not be sufficiently trapped, display defects due to rubbing frequently occurred.

Comparative Example 7
After forming a resin black matrix in the same manner as in Example 1, a colored layer was formed using a photomask different from that in Example 1.

A transparent conductive film was formed in the same manner as in Example 1, and then a spacer was formed using a photomask different from that in Example 1. At this time, the bottom width of the concave portion around the spacer was 0.5 μm, and the level difference between the top of the colored layer formed on the peripheral portion of the resin black matrix and the bottom of the concave portion was 1.4 μm. The spacer bottom area was 30 μm ² .

  As a result, a color filter having the structure shown in the schematic diagram of FIG. 14 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, the display defect due to rubbing hardly occurred, but the cell gap variation was large because the spacer was crushed.

Comparative Example 8
After forming a resin black matrix in the same manner as in Example 1, a colored layer was formed using a photomask different from that in Example 1.

A transparent conductive film was formed in the same manner as in Example 1, and then a spacer was formed using a photomask different from that in Example 1. At this time, the bottom width of the concave portion around the spacer was 0.5 μm, and the level difference between the top of the colored layer formed on the peripheral portion of the resin black matrix and the bottom of the concave portion was 1.4 μm. The spacer bottom area was 450 μm ² .

  Thus, a color filter having the structure shown in the schematic diagram of FIG. 15 was obtained.

  A liquid crystal display device was produced in the same manner as in Example 1 using the obtained color filter. When the display defect occurrence rate due to rubbing in the 50 liquid crystal display devices was examined, the results shown in Table 2 were obtained. Moreover, as a result of measuring cell gap dispersion | variation (standard deviation), the result of Table 2 was obtained. As shown in Table 2, since the spacer was missing due to rubbing, display defects due to rubbing frequently occurred, and the cell gap variation was large.

It is a schematic plan view for demonstrating the colored layer formed in the recessed part around the spacer of this invention, and the resin black matrix peripheral part. It is a schematic plan view for demonstrating the colored layer formed in the recessed part around the spacer of this invention, and the resin black matrix peripheral part. It is a schematic plan view for demonstrating the colored layer formed in the recessed part around the spacer of this invention, and the resin black matrix peripheral part. It is a schematic plan view for demonstrating the colored layer formed in the recessed part around the spacer of this invention, and the resin black matrix peripheral part. It is a schematic cross section which shows an example of the color filter of this invention. It is a schematic cross section which shows an example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is the figure explaining the area | region in which the resin black matrix of this invention was formed. It is a schematic cross section which shows the comparative example of the color filter of this invention. It is a schematic cross section which shows the comparative example of the color filter of this invention.

Explanation of symbols

22: Transparent substrate 24: Resin black matrix 26: Colored layer 26A: Colored layer 26B: Colored layer 28: Flattened layer 30: Spacer 40: Concave portion 41 around the spacer 41: Color formed on the periphery of the resin black matrix around the spacer layer

Claims (4)

A resin black matrix in which a light-shielding agent is dispersed in a resin on a transparent substrate, and red, green, and blue colors on the resin black matrix at the opening of the resin black matrix and the peripheral edge of the opening In the color filter in which a layer is provided and a spacer is provided on the resin black matrix, the color filter laminated on the peripheral edge portion of the opening on the resin black matrix has a region around the spacer. The width of the bottom of the recess is 1.5 to 3.0 μm, and the step between the bottom of the recess and the top of the colored layer laminated on the periphery of the opening of the resin black matrix is 0.2 to 2.0 μm. A color filter characterized by that. The color filter according to claim 1, wherein the spacer bottom area is 50 to 400 μm ² . The color filter according to claim 1, wherein a flattening layer is provided on at least a part of the display area. A liquid crystal display device using the color filter according to claim 1.

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