JP2015138180A - Color filter, liquid crystal display panel, and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color filter that deals with a reduction in light blocking property of a resin black matrix associated with a reduction in the line width of each of black matrices resulting from a reduction in pixel pitch due to high definition, prevents glare of images, provides a high OD value, and can perform display without color mixture when viewed from an oblique angle.SOLUTION: There is provided a color filter having a color filter layer 6 that is formed with pixels on a transparent substrate 1, and black matrices 7 that are each formed between pixels and on the periphery of the pixels, where the transparent substrate 1 has an irregular shape; the recesses 8 of the irregular shape has the black matrix layers formed therein; and the thickness of the black matrix 7 is 1.5 μm or more.

Description

  The present invention relates to a color filter having a color filter layer formed in a pixel shape on a transparent substrate and a black matrix layer composed of a black resin composition formed between pixels and in the periphery of the pixel.

  In general, a color filter for a display device is formed by forming a black matrix layer serving as a light-shielding portion on a transparent substrate at a predetermined position, and then red (Red), green (Green), and blue (Blue) color filter layers on the transparent substrate. Are formed in a pixel shape. As a material for this black matrix layer, a photosensitive resin in which metallic chromium or a black pigment is dispersed is used. The photosensitive resin in which the black pigment is dispersed is made into a coating film because there is a limit to the content of the black pigment to be dispersed in terms of coating suitability, coating film sensitivity, coating film adhesion, and the like. In this case, the optical density of the black matrix layer is about 3.0 to 4.0 at a film thickness of about 1.0 μm.

  Further, when the liquid crystal display device is used, if the light from the outside is reflected by the liquid crystal display device, the display quality is deteriorated. The reflection of light from the outside occurs on the surface and inside of the liquid crystal display device, and is also reflected by the black matrix layer of the color filter. In order to reduce the reflectance of the black matrix layer, a photosensitive resin in which a black pigment is dispersed instead of metallic chromium is used, but the reflectance is about 2 to 5%.

  In addition, in a color filter using a photosensitive resin in which a black pigment is dispersed in a black matrix layer, the pixel periphery of the color filter layer having a thickness of about 1.4 μm is formed on the black matrix layer having a thickness of about 1.0 μm. Since the portions overlap, the thickness of the portion from the transparent substrate is about 1.8 μm. That is, the surface of such a color filter is inferior in flatness as compared with a color filter using metal chromium having a thickness of about 0.2 μm as a black matrix layer.

  In addition, the demand for display devices that have been increasing in demand for OA devices, personal computers, mobile TVs, etc. has become a requirement for high-quality display, and development for high definition is progressing. Has a strong demand for higher definition such as 440 ppi. As the definition becomes higher, the pixel pitch becomes smaller, and there is a problem that the brightness decreases with the same black matrix / TFT wiring line width.

  FIG. 6 shows a cross section of a current liquid crystal display device using a color filter. On the transparent substrate 1, a black matrix layer 7, a red pixel 3, a green pixel 4, a blue pixel 5, and an overcoat layer 9 are shown. The color filter provided with the spacer 10 and the TFT substrate 12 are attached.

  Therefore, it is necessary to reduce the line width of the wiring of the black matrix / TFT substrate, and the bonding accuracy is important. FIG. 7 shows an example in which the bonding accuracy is low, that is, an example of color mixing when viewed from an oblique direction.

As countermeasures, it is conceivable to narrow the gap between the color filter and the TFT substrate 12 and to increase the thickness of the black matrix layer 7. FIG. 8 shows a case where the gap between the color filter and the TFT substrate 12 is narrowed. Color mixing when viewed obliquely disappears, but if the gap between the substrates is narrow, the color filter surface is manufactured due to film thickness unevenness. The possibility that defects will occur increases and productivity may decrease. In addition, since the liquid crystal layer becomes thinner, the black-and-white contrast is lowered, and the smoothness of the color filter surface is affected, so that unevenness is likely to occur, and the required quality for the smoothness of the color filter surface increases (patents). Reference 1).

  On the other hand, as a method for increasing the brightness, the LED luminance can be improved. However, if the black matrix layer has the same light-shielding property, it is transparent. Therefore, in the resin black matrix, it is necessary to increase the light shielding property by increasing the thickness of the black matrix layer (for example, 1.15 → 1.50 μm).

  FIG. 9 shows a case where the film thickness of the black matrix layer 7 is increased. Color mixing when viewed from an oblique direction is eliminated, but it is a trade-off in the process that the line width of the black matrix is reduced and the film thickness is increased at the same time. It's difficult because of the off relationship.

  Further, after forming a black matrix layer after glass etching to increase the thickness, if the thickness of the black matrix layer is the same for red pixels, green pixels, and blue pixels, radiation unevenness is likely to occur.

  Further, in order to improve the display quality of the liquid crystal display device, there is a demand for a material having a reduced black matrix layer reflectivity. A recess for forming the black matrix layer is formed on the glass substrate, and the bottom of the recess is formed. However, it is complicated to make the bottom of the concave portion rough (Patent Document 2).

JP-A-4-223402 Japanese Patent Laid-Open No. 10-325902

  Corresponds to the decrease in the light shielding property of the resin black matrix due to the thinning of the black matrix line width due to the reduction of the pixel pitch due to the high definition, there is no migration, and occurs when the red pixel 3, the green pixel 4 and the blue pixel 5 are formed. An object of the present invention is to provide a color filter in which a high OD value without radiation unevenness is obtained and there is no oblique color mixture.

As means for solving the above-mentioned problems, the invention described in claim 1 includes: a color filter layer formed in a pixel shape on a transparent substrate; and a black matrix formed between pixels and in a pixel periphery. A color filter comprising:
The transparent substrate has an uneven shape, and the black matrix is formed in the recessed portion of the uneven shape,
The black filter has a thickness of 1.50 μm or more.

  The invention according to claim 2 is the color filter according to claim 1, wherein the black matrix is composed of at least two layers.

  The invention according to claim 3 is the color filter according to claim 1 or 2, wherein the black matrix includes a low reflection layer.

The invention according to claim 4 is the color filter according to any one of claims 1 to 3, wherein the black matrix is thinner than the depth of the recess.

  The invention according to claim 5 is characterized in that the transparent substrate is formed by patterning a transparent material on a flat transparent base material. This is a color filter.

  According to a sixth aspect of the present invention, there is provided a liquid crystal display panel including the color filter according to any one of the first to fifth aspects.

  A seventh aspect of the present invention is a liquid crystal display device including the liquid crystal display panel according to the sixth aspect.

  According to the present invention, it is possible to provide a color filter that does not reduce visibility from an oblique direction even if the black matrix line width is reduced by reducing the pixel pitch due to higher definition. Further, when a low reflection material is formed under the resin black matrix, it is possible to reduce reflection of an image due to reflection.

1 is a conceptual cross-sectional view illustrating a configuration of a color filter of the present invention. It is the cross-sectional conceptual diagram which showed the structure which made the black matrix thickness thin with respect to the depth of a recessed part of the color filter of this invention. It is the cross-sectional conceptual diagram which showed the structure which provided the recessed part by the etching of the color filter of this invention, and formed the low reflection resist layer in the recessed part. It is the cross-sectional conceptual diagram which showed the structure which provided the recessed part of this invention by patterning of a transparent material. It is the cross-sectional conceptual diagram which showed the structure which formed the low reflection layer in the recessed part provided by patterning of the transparent material of this invention. It is the cross-sectional conceptual diagram which showed the structure of the general liquid crystal display panel. FIG. 6 is a conceptual cross-sectional view showing color mixing that occurs when a deviation occurs in the bonding of a TFT substrate and a color filter in a liquid crystal display panel. It is a cross-sectional conceptual diagram explaining avoidance of color mixing by reducing the gap between the TFT substrate and the color filter. It is a cross-sectional conceptual diagram explaining avoidance of color mixing by increasing the thickness of a black matrix.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 shows an example of the configuration of the color filter of the present invention. A transparent substrate 1 is formed by forming a recess 8 on a flat transparent substrate by etching, and a black matrix 7 is formed in the recess 8. Formed. Further, a color layer including red pixels 3, green pixels 4, and blue pixels 5 is formed thereon, and an overcoat layer 9 is formed on the surface as necessary, thereby forming a color filter substrate 11. The formed color filter 11 is bonded to the TFT substrate 12 to form a liquid crystal display panel. The positional relationship among the red pixel 3, the green pixel 4, and the blue pixel 5 shown in FIG. 1 is merely an example of the color filter according to the present invention, and the positional relationship is not limited to the above example. .

In the case of high-definition displays, if only the pixel pitch width is reduced while the line width of the black matrix / TFT wiring is kept constant, the area ratio of the black matrix occupying the area of the entire effective area of the color filter increases. As a result, the amount of light transmitted through the backlight decreases and the brightness decreases. Therefore, it is preferable that the line width of the black matrix is also reduced, specifically, at least 5 μm or less, more preferably 4 μm or less. In this case, the thickness of the black matrix is preferably 1.50 μm or more from the viewpoint of suppressing the oblique visibility reduction. The black matrix 7 is formed in the concave portion 8 as shown in FIG. 1, thereby reducing the irregularities on the surface of the final color filter substrate. Moreover, it is preferable that the depth of a recessed part is 20% or more with respect to the thickness of a black matrix.

  FIG. 2 shows an example of another configuration of the color filter of the present invention. The color filter shown in FIG. 2 shows a configuration in which the thickness of the black matrix 7 is formed lower than the depth of the recess formed on the transparent substrate 1, and the surface of the surface is maintained while maintaining the thickness of the black matrix. A color filter with improved flatness can be formed.

  FIG. 3 shows an example of still another configuration of the color filter of the present invention. The color filter shown in FIG. 3 is obtained by forming a black matrix 7 having a two-layer structure in a recess formed on a transparent substrate 1. Each layer constituting the black matrix 7 of the color filter shown in FIG. 3 may be formed in any way as long as at least one of the layers has a certain light shielding property. For example, the layers shown in FIG. Similarly, by forming the layer on the transparent substrate 1 side as the low-reflection resist layer 14, it is possible to reduce the reflection of an image due to reflection. Moreover, in the color filter according to the present invention, the black matrix 7 does not prevent the black matrix 7 from being composed of a plurality of layers of three or more layers as necessary. Alternatively, the black matrix 7 may have a conductive layer in any of the layers.

  FIG. 4 shows an example of still another configuration of the color filter of the present invention. The color filter shown in FIG. 4 is obtained by patterning a transparent material on a flat transparent substrate to provide irregularities. As the transparent material, a photosensitive resin having transparency, a transparent resin ink, or the like can be used. A concave portion can be formed by applying a pattern to the transparent material by means of printing or the like and curing it as necessary. When a transparent substrate is formed by such a method, for example, it is not necessary to use a chemical solution such as hydrofluoric acid that is used in glass etching or the like, so that a color filter can be manufactured more safely.

  FIG. 5 shows an example of another configuration of the color filter of the present invention. The color filter shown in FIG. 5 uses a transparent substrate in which concave portions are formed by patterning a transparent material on a flat transparent substrate, and a black matrix having a two-layer structure is formed in the concave portions. Further, by forming the layer on the transparent substrate 1 side as the low reflection resist layer 14, it is possible to reduce the reflection of an image due to reflection, as in the configuration shown in FIG.

  The transparent substrate used in the color filter according to the present invention may be any substrate that has a certain transmittance with respect to visible light. Those having a transmittance of preferably 80% or more can be suitably used. For example, various glass substrates such as quartz glass, borosilicate glass, and aluminosilicate glass, or various plastic substrates such as polyester resin and polyolefin resin. Can be used.

As the black matrix, a metal chromium thin film that has been used in the past, or a material such as a black photosensitive resin composition containing a light shielding material can be used. Further, as described above, when the black matrix is composed of two or more layers, the black matrix can be formed using different materials having different compositions and refractive indexes. When the black matrix is composed of two or more layers, the thickness that can be occupied by one of the layers is, of course, a part of the thickness of the entire black matrix. By forming the black matrix, the black matrix is formed thicker than the general level, so it is easy to form a multi-layer structure of two or more layers while obtaining the effect of reducing oblique visibility. Become.

  Hereinafter, a configuration example of the black matrix when the black matrix is formed in a two-layer configuration is shown. For example, the black matrix is formed by laminating a coating film of a first black photosensitive resin composition and a second black photosensitive resin composition containing a black pigment, a binder resin, a polymerizable monomer, a photopolymerization initiator, and a solvent. Can be formed. The black matrix obtained by laminating the first black photosensitive resin coating film and the second black photosensitive resin coating film preferably has an OD value of 4.0 / μm or more.

  The first black photosensitive resin composition preferably has an OD value per 1.0 μm of 1.0 / μm or less, more preferably 0.8 / μm or less. When the OD value is 0.8 / μm or less, the difference in refractive index from the glass substrate becomes small, and reflection at the interface between the transparent substrate 1 and the first black photosensitive resin coating film can be suppressed. Furthermore, since the reflected light at the interface between the first black photosensitive resin coating film and the second black photosensitive resin coating film 4 is absorbed, the total reflectance can be reduced.

  The film thickness of the first black photosensitive resin coating film is preferably in the range of 0.5 to 1.0 μm, more preferably in the range of 0.5 to 0.8 μm. When the film thickness is 0.5 μm or less, coating becomes difficult. Further, by suppressing the film thickness to 0.8 μm or less, it is possible to obtain suitable flatness when used for a color filter.

  The second black photosensitive resin coating film preferably has an OD value per 1.0 μm of 3.4 / μm or more. When the OD value is 3.4 / μm or more, it is possible to obtain a sufficient light shielding property as a black matrix without impairing the flatness.

  The film thickness of the second black photosensitive resin coating film is preferably in the range of 1.1 to 1.7 μm, more preferably in the range of 1.1 to 1.5 μm. When the film thickness is 1.1 μm or more, a sufficiently high light shielding property can be obtained. Further, by suppressing the film thickness to 1.5 μm or less, it is possible to obtain suitable flatness when used for a color filter.

  Hereinafter, the material example used for the black photosensitive resin composition which forms a 1st and 2nd coating film when a black matrix is made into 2 layer structure is demonstrated in detail. For example, the black photosensitive resin composition can be used containing at least a black pigment, a binder resin, a polymerizable monomer, a photopolymerization initiator, and a solvent.

<Black pigment>
Carbon black is preferably used as the black pigment. As carbon black, any of lamp black, acetylene black, thermal black, channel black, furnace black and the like may be used.

  The content of carbon black in the first black photosensitive resin composition is preferably 20% by weight or less, more preferably 15% by weight or less in the solid content. When content is 20 weight% or more, the reflection in the interface of the transparent substrate and the coating film of a 1st black photosensitive resin composition becomes large.

  The content of carbon black in the second black photosensitive resin composition is preferably 40 to 60 weight percent, more preferably 45 to 55 weight percent in the solid content. When the content is 40% by weight or less, the black matrix has insufficient light shielding properties. On the other hand, when content is 60 weight% or more, the sensitivity of a black photosensitive resin composition falls and linearity deteriorates.

<Binder resin>
The first black photosensitive resin composition of the present invention is characterized by using a polyimide precursor as a binder resin. The polyimide precursor is generally synthesized by addition polymerization of tetracarboxylic dianhydride and a diamine compound. Since the polyimide precursor has many carboxyl groups, it has alkali developability. A polyimide resin is obtained by imidizing the polyimide precursor at a high temperature of 200 ° C. or higher.

  Since the polyimide precursor has a high polarity, the coating film using the polyimide precursor as a binder resin is cyclohexanone, propylene glycol, which is a solvent for a black photosensitive resin composition used for the production of a general black matrix without high-temperature treatment. Insoluble in monomethyl ether acetate and the like. For this reason, after forming a coating film of the first black photosensitive resin composition of the present invention using a polyimide precursor as a binder resin, cyclohexanone, propylene glycol monomethyl ether acetate or the like is used as a solvent while maintaining developability. It is possible to laminate the second black photosensitive resin composition of the present invention.

  The tetracarboxylic dianhydrides that synthesize polyimide precursors are 4,4'-oxydiphthalic dianhydride, 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride, pyromellitic dianhydride 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic acid Dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-paraterphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′- Aromatic compounds such as metaterphenyl tetracarboxylic dianhydride are preferably used from the viewpoints of heat resistance and insulation.

  It is also possible to use an alicyclic compound as the tetracarboxylic dianhydride. Examples of the alicyclic tetracarboxylic dianhydride include 1,2,4,5-cyclohexanetetracarboxylic dianhydride, bicyclo [2,2,2] oct-7-ene-2,3,5,6- Tetracarboxylic dianhydride, bicyclo [2,2,1] heptane-2-endo-3-endo-5-exo-6-exo-2,3,5,6-tetracarboxylic dianhydride, bicyclo [ 2,2,1] heptane-2-exo-3-exo-5-exo-6-exo-2,3,5,6-tetracarboxylic dianhydride, bicyclo [2,2,1] heptane-2 3,5,6-tetracarboxylic dianhydride, decahydro-dimethananaphthalene tetracarboxylic dianhydride, and the like.

  Examples of the diamine compound for synthesizing the polyimide precursor include paraphenylene diamine, metaphenylene diamine, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'- Diaminodiphenylmethane, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfide, 1,3-bis (4-aminophenoxy) Aromatic compounds such as benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2-bis (trifluoromethyl) benzidine, 9,9'-bis (4-aminophenyl) fluorene are heat resistant and insulated It is preferably used from the viewpoint of sex.

  It is also possible to use an alicyclic compound as the diamine compound. Examples of the alicyclic diamine compound include bis [2- (3-aminopropoxy) ethyl] ether, 1,4-butanediol-bis (3-aminopropyl) ether, and 3,9-bis (3-aminopropyl). ) -2,4,8,10-tetraspiro-5,5-undecane, 1,2-bis (2-aminoethoxy) ethane, 1,2-bis (3-aminopropoxy) ethane, triethylene glycol-bis ( 3-aminopropyl) ether, polyethylene glycol-bis (3-aminopropyl) ether, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraspiro-5,5-undecane, 1,4 -Butanediol-bis (3-aminopropyl) ether and the like.

  In the second black photosensitive resin composition, a cardo resin can be used as the binder resin. This makes it possible to accurately form a high-definition pattern having a line width of 6 μm or less, which is required for a recent black matrix.

  The cardo resin is a resin having a skeleton in which two cyclic structures are bonded to quaternary carbon atoms constituting the cyclic structure. In general, the fluorene ring has a skeleton in which a benzene ring is bonded. The epoxy compound represented by the chemical formula (1) is reacted with (meth) acrylic acid, and the resulting epoxy acrylate is reacted with an acid anhydride. Synthesized. Acid anhydrides used in the synthesis of cardo resins include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyl end methylenetetrahydrophthalic anhydride, chlorendic anhydride Examples include acid, methyltetrahydrophthalic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, biphenyl ether tetracarboxylic dianhydride, and the like.

<Polymerizable monomer>
Examples of the photopolymerizable monomer include ethylene glycol (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polypropylene glycol. Di (meth) acrylate, hexane di (meth) acrylate, neopentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, glycerin tri (meth) acrylate, glycerin tetra (meth) acrylate, tetratrimethylolpropane tri (meth) Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta ( Data) acrylate, dipentaerythritol hexa (meth) acrylate and the like, these components are used alone or as a mixture. Various modified (meth) acrylates, urethane (meth) acrylates, and the like can also be used. Among these, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate, which have a small double bond equivalent and can achieve high sensitivity, are preferably used.

  As content of a photopolymerizable monomer, it is preferable that it is 5 to 20 weight% in solid content of a black photosensitive resin composition, More preferably, it is the range of 10 to 15 weight%. When the content of the photopolymerizable monomer is within this range, the sensitivity and development speed of the black photosensitive resin composition can be adjusted to a level suitable for production. When the content of the photopolymerizable monomer is 5% by weight or less, the sensitivity of the black photosensitive resin composition is insufficient.

<Photopolymerization initiator>
Conventionally known compounds can be appropriately used as a photopolymerization initiator, but an oxime ester compound that can achieve high sensitivity even when used in a black photosensitive resin composition that does not transmit light is used. Is preferred.

  Specific examples of the oxime ester compound include 2- (O-benzoyloxime) -1- [4- (phenylthio) phenyl] -1,2-octanedione, 1- (O-acetyloxime) -1- [9. -Ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] ethanone (both manufactured by BASF Japan Ltd.) and the like.

  The content of the oxime ester compound is preferably 1 to 10% by weight, more preferably 2 to 5% by weight, based on the solid content of the black photosensitive resin composition. When the content of the photopolymerization initiator is 1% by weight or less, the sensitivity of the black photosensitive resin composition is insufficient. On the other hand, when the content of the photopolymerization initiator is 10% by weight or more, the pattern line width of the black matrix becomes too thick.

  In the black photosensitive resin composition, other photopolymerization initiators can be used in combination with the above oxime ester compound, and 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- ( 4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, Acetophenone compounds such as 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyldimethyl ketal Compounds, Benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylper Benzophenone compounds such as oxycarbonyl) benzophenone, thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-diethylthioxanthone, 2,4,6- Trichloro-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-tria 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-piperonyl-4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) ) -6-styryl-s-triazine, 2- (naphth-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxy-naphth-1-yl) -4 Triazine compounds such as 6-bis (trichloromethyl) -s-triazine, 2,4-trichloromethyl- (piperonyl) -6-triazine, 2,4-trichloromethyl (4′-methoxystyryl) -6-triazine, Phosphines such as bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide Compound, 9,10-phenanthrenequinone, camphor quinone, quinone-based compounds such as ethyl anthraquinone, borate compounds, carbazole compounds, imidazole compounds, titanocene compounds and the like.

  These photopolymerization initiators can be used alone or in combination of two or more at any ratio as required. The content of the other photopolymerization initiator is preferably 0.1 to 1% by weight, more preferably 0.2 to 0.5% by weight in the solid content of the black photosensitive resin composition. is there.

<Solvent>
Examples of the solvent for the first black photosensitive resin composition include amides such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, and N, N-dimethylformamide, β-propiolactone, γ-butyrolactone, Polar solvents such as lactones such as γ-valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone are used, and N-methyl-2-pyrrolidone and γ-butyrolactone are preferred. Also good.

Solvents for the second black photosensitive resin composition include cyclohexanone, ethylbenzene, xylene, isoamyl acetate, n amyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate (PGMAC), propylene glycol monoethyl ether, propylene glycol mono Ethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monomethyl ether acetate , Triethylene glycol monoethyl ether, triethylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoethyl ether acetate, ethyl lactate, ethyl Ethoxypropionate is used, and cyclohexanone and PGMAC are preferable, and these may be used in combination.

<Other additives>
The black photosensitive resin composition can be used in combination with a surfactant for further improving the coating property, a silane coupling agent for improving the adhesion to the substrate, and the like.

  Examples of the surfactant include fluorine surfactants such as perfluoroalkyl phosphates and perfluoroalkyl carboxylates, anionic surfactants such as higher fatty acid alkali salts, alkyl sulfonates, and alkyl sulfates, and higher amines. Cationic surfactants such as halogenates and quaternary ammonium salts, nonionic surfactants such as polyethylene glycol alkyl ethers, polyethylene glycol fatty acid esters, sorbitan fatty acid esters and fatty acid monoglycerides, amphoteric surfactants, silicone surfactants Surfactants such as agents can be used, and these may be used in combination.

  As silane coupling agents, vinyl silanes such as vinyltrimethoxysilane and vinyltriethoxysilane, epoxy silanes such as 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and 3-glycidoxypropyldimethoxysilane, Methacrylsilanes such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, N- Aminosilanes such as phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, mercaptosilanes such as 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltrieth Isocyanate silanes such as Shishiran like.

<Transparent substrate>
The transparent substrate forming the black matrix preferably has a certain degree of transmittance with respect to visible light, and more preferably has a transmittance of 80% or more. Examples thereof include various glass substrates such as quartz glass, borosilicate glass, and aluminosilicate glass, and various plastic substrates such as polyester resin and polyolefin resin.

  The transparent substrate on which the black matrix of the present invention is formed has a reflectance of 5.0% or less when measured from the transparent substrate side where the black matrix is not formed. Reflection of external light in the apparatus is reduced, and good display characteristics can be obtained.

<Color filter>
The color filter forms red, green, and blue colored pixels in an opening on a transparent substrate having a recess in which the black matrix is formed.

  Examples of red pigments used for forming red pixels include C.I. I. Pigment Red 7, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 3, 81: 4, 146, 168, 177, 178, 179, 184, 185, 187, 200, 202, 208, 210, 246, 254, 255, 264, 270, 272, 279 and the like.

  In order to adjust the hue of the red pixel, a yellow pigment can be used in combination. Specific examples of yellow pigments include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 126, 127, 128, 129, 138, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 85,187,188,193,194,198,199,213,214, and the like.

  Specific examples of the green pigment used for forming the green pixel include C.I. I. Pigment green 7, 10, 36, 37, 58, and the like. It is also possible to use a yellow pigment in combination to adjust the hue of the green pixel. As a yellow pigment, what was illustrated for hue adjustment of a red pixel can be used suitably.

  Specific examples of blue pigments used to form blue pixels include C.I. I. Pigment blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64, and the like. Further, a purple pigment can be used in combination to adjust the hue of the blue pixel. Specific examples of purple pigments include C.I. I. Pigment violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, 50 and the like.

  By using the color filter having the above-described configuration, it is possible to manufacture a liquid crystal display device in which a reduction in oblique visibility is suppressed.

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Pixel 3 ... Red pixel 4 ... Green pixel 5 ... Blue pixel 6 ... Color filter layer 7 ... Black matrix 8 ... Concave 9 ... -Overcoat layer 10 ... Spacer 11 ... Color filter substrate 12 ... TFT substrate 13 ... Transparent material 14 ... Low reflection layer

Claims (7)

A color filter having a color filter layer formed in a pixel shape on a transparent substrate, and a black matrix formed between pixels and around the pixel,
The transparent substrate has an uneven shape, and the black matrix is formed in the recessed portion of the uneven shape,
A color filter, wherein the black matrix has a thickness of 1.50 μm or more.   The color filter according to claim 1, wherein the black matrix includes at least two layers.   The color filter according to claim 1, wherein the black matrix includes a low reflection layer.   The color filter according to any one of claims 1 to 3, wherein the black matrix has a thickness smaller than a depth of the concave portion.   The color filter according to any one of claims 1 to 4, wherein the transparent substrate is formed by patterning a transparent material on a flat transparent substrate.   A liquid crystal display panel comprising the color filter according to claim 1.   A liquid crystal display device comprising the liquid crystal display panel according to claim 6.