JP2011158537A - Color filter substrate and photosensitive coloring composition used for manufacture of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter substrate capable of reducing a difference of film thickness between a pixel part and a photosensitive coloring composition of a part which runs on BM when having priority on the film thickness of a coloring pixel and controlling laminating PS in desired height, and to provide the photosensitive coloring composition capable of being used for its manufacture. <P>SOLUTION: The color filter substrate having a laminated photo-spacer formed by laminating a black matrix, a plurality of colors of the coloring pixels, and the photosensitive coloring composition composing the coloring pixels on the black matrix on a substrate in one color or more contains a transparent pigment of 1-30 mass% in the whole solid content of the photosensitive coloring composition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a color filter substrate used for a liquid crystal display device or a color image pickup tube element, and a photosensitive coloring composition used for the production thereof.

  In an active matrix liquid crystal display device, generally, a substrate in which an active element (thin film transistor, TFT) is formed for each pixel on a glass substrate, and a color filter substrate in which a color filter and a uniform transparent electrode are formed on the glass substrate. Are arranged opposite to each other with a liquid crystal interposed therebetween. The shutter action of the liquid crystal of each pixel is controlled by the switching action of each TFT element of the TFT substrate (hereinafter, the substrate on which the active element is formed is abbreviated as TFT substrate).

  In a liquid crystal display device using TFTs, a TFT substrate and a color filter substrate are arranged to face each other with a predetermined interval, and the liquid crystal is sandwiched between sealing materials in which reinforcing fibers are mixed with epoxy resin or the like. It is composed by pasting together. Liquid crystal is sealed between the color filter substrate and the TFT substrate, but if the distance between the color filter substrate and the TFT substrate is not accurately maintained, the thickness of the liquid crystal layer will differ, resulting in a difference in the optical rotation characteristics of the liquid crystal. This causes a phenomenon that coloring is caused by or a partial color unevenness occurs and the image is not displayed correctly. Conventionally, in a liquid crystal display device, in order to ensure a uniform cell gap between a TFT substrate and a color filter substrate, glass called a spacer or resin transparent spherical particles (beads) are interposed between these substrates. However, there may be a phenomenon that the spacers are not uniformly dispersed and the spacers are partially biased. When such a phenomenon occurs, the display quality of the portion where the spacers are gathered deteriorates, and there is a problem in terms of accurately maintaining the interval.

  Therefore, a method of forming columnar protrusions having a diameter of 10 μm to 50 μm called spacers on the liquid crystal has been proposed. Patent Documents 1 to 4 disclose a technique for forming a spacer for a liquid crystal display device on a color filter substrate by a photolithography technique. Patent Documents 5 to 7 disclose a technique of a stacked PS (Photo Spacer) in which a spacer for a liquid crystal display device is formed by overlapping colored layers without increasing the number of processes.

  The laminated PS is usually formed by overlaying a plurality of photosensitive coloring compositions on a black matrix (BM) so as not to lower the aperture ratio of the color filter. However, since the coloring composition has poor wettability to the hard film, a repelling phenomenon occurs, and the coloring composition flows into the pixel region in the post-baking process, so that the coloring is formed on the narrow BM portion. The film thickness of the composition is thinner than the film thickness of the pixel flat portion, and the necessary PS stacking height is obtained by overlapping two colors and three colors. Therefore, when priority is given to the thickness of the colored pixels in order to obtain a desired hue, it is difficult to control the stacked PS to a desired height.

JP 9-258192 A Japanese Patent Laid-Open No. 11-248921 JP 2001-201750 A Japanese Patent Laid-Open No. 2001-108813 JP-A-4-93924 JP-A-4-184423 JP 2007-212826 A

  The present invention has been made in view of the above problems, and when priority is given to the thickness of the colored pixel, the difference in film thickness between the pixel portion and the photosensitive coloring composition on the BM is reduced. It is an object of the present invention to provide a color filter substrate capable of controlling the laminated PS to a desired height and a photosensitive coloring composition that can be used in the production thereof.

The invention according to claim 1 of the present invention is a laminate formed by laminating at least one color of a black matrix, a plurality of colored pixels on a substrate, and a photosensitive coloring composition constituting the colored pixels on the black matrix. In a color filter substrate having a photo spacer,
1 to 30% by mass of a transparent extender pigment is contained in the total solid content of the photosensitive coloring composition.

Next, the invention according to claim 2 of the present invention is a photosensitive coloring composition used for forming colored pixels and laminated photospacers of the color filter substrate according to claim 1,
It is a photosensitive coloring composition comprising at least a coloring pigment or dye, a transparent resin, a photopolymerizable monomer, a photopolymerization initiator, a solvent, and a transparent extender pigment, and 1 to 30% by mass of a transparent extender in the total solid content. It is a photosensitive coloring composition characterized by containing a pigment.

  The invention according to claim 3 of the present invention is characterized in that the transparent extender pigment is at least one selected from the group consisting of silicon oxide, barium sulfate, aluminum oxide, calcium carbonate, and magnesium carbonate. The photosensitive coloring composition described in 1.

  According to the color filter substrate and the photosensitive coloring composition of the present invention, the photosensitive coloring composition forming the pixel and the laminated PS contains 1 to 30% by mass of a transparent extender pigment in the total solid content. Therefore, the fluidity of the photosensitive coloring composition can be controlled to be low, the repelling phenomenon to the hard film of the coloring composition of BM or other colors hardly occurs, and the coloring composition flows into the pixel region even in the post-baking process. Less. For this reason, the running rate compared with the film thickness of the pixel flat portion of the colored composition formed on and formed on the BM portion is increased. It is possible to obtain the necessary PS stacking height with the coloring composition. That is, a great cost reduction effect can be obtained in which the amount of the photosensitive coloring composition applied in the photolithography process can be reduced, or the number of colors in the stack can be reduced.

The schematic diagram which shows the color filter substrate of an example which formed laminated | stacked PS in a partial cross section. Explanatory drawing which shows the film thickness of the coloring composition which carried on the coloring pixel and BM of the color filter substrate which concerns on this invention in a cross section. The graph which shows the relationship between the total pigment ratio in the blue photosensitive coloring composition which concerns on this invention, and a climbing rate. The graph which shows the relationship between the transparent extender pigment ratio in the blue photosensitive coloring composition which concerns on this invention, and a climbing rate.

  The color filter substrate of the present invention and the photosensitive coloring composition used therefor will be described in detail below based on one embodiment.

  The color filter substrate of the present invention comprises a substrate (1) having a black matrix (2), a plurality of colored pixels (3), and one or more photosensitive coloring compositions constituting the colored pixels laminated on the black matrix. It has the laminated photo spacer (4) formed. The color filter substrate of the present invention is characterized in that 1 to 30% by mass of a transparent extender pigment is contained in the entire solid text of the photosensitive coloring composition. The photosensitive coloring composition according to the present invention is a photosensitive coloring composition comprising at least a coloring pigment or dye, a transparent resin, a photopolymerizable monomer, a photopolymerization initiator, a solvent, and a transparent extender pigment, It is a photosensitive coloring composition characterized by containing 1 to 30% by mass of a transparent extender pigment in a solid sentence.

  As a method for forming colored pixels and a black matrix on a transparent substrate, a pigment dispersion method has become the mainstream. In the pigment dispersion method, a color filter is formed of a plurality of colored layers (red, green, blue, etc.) by patterning a coating layer of a photosensitive coloring composition in which a coloring material such as an organic pigment is dispersed by a known photolithography method. This is a method of forming a pixel. Although the order of coloration of the plurality of colored layers is not limited, red pixels, green pixels, and blue pixels are formed by applying the colored layer, exposing, developing, etc. after forming the pattern of the black matrix layer due to the convenience of alignment and the formability of the laminated PS. Etc. are sequentially formed, and a stacked PS having a desired height is formed simultaneously with the pixel formation.

  In the case where a colored layer is used as a spacer, the stacked portion stacks one or more colored layers on the black matrix layer. The number of colors to be superimposed is defined by the cell gap necessary for the liquid crystal display device, but preferably two to three colors. In the case of stacking two colors, when the red and blue colored layers are stacked, the color becomes close to black, which prevents color mixture in the pixel portion when color misregistration occurs. Alternatively, by using two types of stacked portions of two colors and three colors, the lower stacked portion can be used as a sub-spacer. The sub-spacer serves as a spacer that prevents cell destruction when a large pressure is applied to the liquid crystal panel during use as a display device. The formation ratio of the spacer and the sub-spacer is not limited, but about 1: 2 (the latter is the sub-spacer) is practical. Alternatively, for example, it can be formed as a laminated portion of two colors, and can be used as a spacer or sub-spacer depending on whether or not a protrusion is further formed on the laminated portion.

  In a normal color filter substrate, the black matrix layer has a thickness of 0.5 to 3 μm and a width of 3 to 30 μm. The film thickness (thickness) of each of the red pixel, the green pixel, and the blue pixel is 0.5 to 3 μm. This film thickness largely depends on the composition of the photosensitive coloring composition and the coating method, but when the film thickness of each pixel is formed at about 1.8 μm using a conventional photosensitive coloring composition, for example, As shown in FIG. 1, the thickness of the red layer (4R) formed on the black matrix (2) is about 1.40 μm, and the thickness of the green layer (4G) formed on the black matrix (2) is 0. Further, the thickness of the blue layer (4B) formed and formed thereon tends to be as thin as about 0.88 μm. That is, when priority is given to the thickness of the colored pixels in order to obtain a desired hue, it is difficult to control the stacked PS (4) to a desired height.

The black matrix layer is a thin light-shielding pattern formed between the pixels for increasing the contrast of a liquid crystal display device formed using a black resin. As a method for forming the black matrix layer, a protective resist is formed by photolithography using a black non-photosensitive resin and formed into a matrix by etching, or a matrix is formed by photolithography using a black photosensitive resin. There is a method of forming. As the black color material, carbon black, titanium oxide, or a plurality of organic pigments can be used.

  As described above, the photosensitive coloring composition according to the present invention comprises at least a coloring pigment or dye, a transparent resin, a photopolymerizable monomer, a photopolymerization initiator, a solvent, and a transparent extender pigment. The black photosensitive resin and photosensitive coloring composition used for the formation of the black matrix and the colored pixel are, for example, a pigment component dispersed in a transparent resin binder using a dispersant, and a photopolymerizable monomer and photopolymerization in this dispersion. It is prepared by adding an initiator, a sensitizer, a solvent and the like. The photosensitive coloring composition is further adjusted by adding 1 to 30% by mass of a transparent extender pigment in the total solid sentence.

  In the embodiment of the present invention, the black photosensitive resin and the photosensitive coloring composition used for forming the black matrix and the colored pixel are mainly composed of a resin binder and an initiator, and the resin binder is photopolymerized or thermally polymerized, or It undergoes three-dimensional crosslinking through photopolymerization and thermal polymerization. By three-dimensionally crosslinking the black matrix and the resin binder of the coloring composition, it is possible to suppress the thickness of the black matrix and the colored pixels and the laminated PS from being reduced by the load in the panel assembling process.

  Examples of resin binders suitable for photopolymerization include acrylate resins, examples of resin binders suitable for thermal polymerization include epoxy resins, and examples of resin binders suitable for photopolymerization and thermal polymerization include epoxy acrylate resins. It is done.

  As a coloring pigment contained in the photosensitive coloring composition according to the present invention, a commercially available organic pigment can be used. Moreover, a dye, a natural pigment, and an inorganic pigment can be used in combination according to the hue of the filter segment to be formed. As the organic pigment, those having high color developability and high heat resistance, particularly high heat decomposition resistance are preferably used. An organic pigment can be used individually by 1 type or in mixture of 2 or more types. Further, the organic pigment may be refined by salt milling, acid pasting or the like.

  Below, the specific example of the organic pigment which can be used for the photosensitive coloring composition which concerns on this invention is shown by a color index (CI) number. For the red pixel, for example, C.I. I. Pigment Red 7, 14, 41, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 3, 81: 4, 146, 168, 177, 178, 179, 184, 185, Red pigments such as 187, 200, 202, 208, 210, 246, 254, 255, 264, 270, 272, and 279 can be used, and a yellow pigment and an orange pigment can also be used in combination.

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, 139, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180 181,182,187,188,193,194,199,198,213,214, and the like. Examples of the orange pigment include C.I. I. Pigment Orange 36, 43, 51, 55, 59, 6
1, 71, 73, and the like.

  In the case where the red pixel contains one or more of diketopyrrolopyrrole red pigment and anthraquinone red pigment among these pigments, it is easy to obtain an arbitrary Rth (retardation value), which is preferable. . This is because the diketopyrrolopyrrole red pigment can be made positive or negative by devising the finer treatment, and its absolute value can be controlled to some extent. In addition, anthraquinone-based red pigments easily obtain Rth close to 0 regardless of the refinement treatment.

  The amount used is 10 to 90% by mass of the diketopyrrolopyrrole red pigment and 5 to 70% by mass of the anthraquinone red pigment based on the total mass of the pigment. From the viewpoint of contrast and the like. In particular, when focusing on contrast, it is more preferable that the diketopyrrolopyrrole red pigment is 25 to 75% by mass and the anthraquinone red pigment is 30 to 60% by mass.

  For example, C.I. I. Green pigments such as Pigment Green 7, 10, 36, 37, and 58 can be used, and a yellow pigment can be used in combination. As the yellow pigment, the same pigments as those used for the red pixel can be used.

Examples of 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 can be used, and a purple pigment can be used in combination. Examples of purple pigments include C.I. I. Pigment
Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, 50 etc. are mentioned.

  When the blue pixel contains at least one of a metal phthalocyanine blue pigment and a dioxazine purple pigment among these pigments, it is easy to obtain a phase difference close to zero. The amount used is 40 to 100% by mass of the metal phthalocyanine blue pigment and 1 to 50% by mass of the dioxazine violet pigment based on the total mass of the pigment. It is preferable from the point. Further, it is more preferable that the metal phthalocyanine blue pigment is 50 to 98% by mass and the dioxazine violet pigment is 2 to 25% by mass. In the above, examples of the metal phthalocyanine blue pigment include C.I. I. Pigment Blue 15: 6, and dioxazine-based purple pigments include C.I. I. Pigment Violet 23 is preferable in terms of excellent light resistance, heat resistance, transparency, coloring power, and the like.

  The transparent extender pigment contained in the photosensitive coloring composition of the present invention may be at least one selected from the group consisting of silicon oxide (silica), barium sulfate, aluminum oxide, calcium carbonate, and magnesium carbonate. Moreover, it is preferable that the average particle diameter of an extender is 500 nm or less from a transparency point. In particular, fine powder silica gel having a refractive index close to that of a binder resin, excellent dispersibility in the resin, and exhibiting thickening can be more preferably used.

  In the photosensitive coloring composition which concerns on this invention, 1-30 mass% with respect to the total solid of a photosensitive coloring composition, Preferably it contains 5-25 mass% transparent extender pigment. In addition, it is preferable that the solid content amount which combined the above-mentioned coloring pigment and transparent extender pigment shall be 20-55 mass% with respect to the total solid of a photosensitive coloring composition. When the amount of the transparent extender pigment contained in the total solid content of the photosensitive coloring composition is less than 1% by mass, the thickening effect is not exhibited. When the amount exceeds 30% by mass, the contrast is greatly reduced and the cross-sectional shape of the film is inversely tapered. The problem that becomes. Further, if the total solid content of the colored pigment and the transparent extender pigment exceeds 55% by mass, the photopolymerizable monomer and the photopolymerization initiator must be reduced, and pixel formation cannot be performed.

  As described above, by containing a transparent extender pigment in the photosensitive coloring composition, the fluidity of the photosensitive coloring composition can be controlled to be low, and the BM or other colored coloring composition can be repelled onto the hardened material. The phenomenon hardly occurs, and the coloring composition does not flow into the pixel region even in the post-baking process. For this reason, the running rate compared with the film thickness of the pixel flat portion of the colored composition formed on and formed on the BM portion is increased. It is possible to obtain the necessary PS stacking height with the coloring composition. As will be described later, since a certain degree of linear relationship is obtained between the content of the transparent extender pigment and the climbing rate, even if the content of the colored pigment and the thickness of the colored pixel are prioritized in favor of the hue, the transparent extender It is possible to control the height of the laminated PS by changing the pigment content.

  The transparent resin is a resin that disperses the color pigment and the transparent extender pigment, and is a resin in which an unexposed portion can be dissolved and removed by an alkaline developer in the development after the pixel pattern exposure. Specifically, acrylic monomers such as alkyl acrylates, cyclic acrylates, cyclic methacrylates, hydroxyethyl ethyl acrylates, hydroxyethyl methacrylates, acrylic transparent resins composed of radical polymerizable monomers having ethylenically unsaturated groups, fluorene skeletons Epoxy acrylate transparent resin having a functional group or a polyfunctional epoxy resin in which a radical polymerizable monomer having an ethylenically unsaturated group is added can be used. However, it is not limited to the above resin.

  As a photopolymerizable monomer, for example, the following monomers can be mixed or used alone. For example, monomers containing a hydroxyl group such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, Triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol di (meth) ) Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate , (Meth) acrylic esters such as dipentaerythritol hexa (meth) acrylate, glycerol (meth) acrylate, or pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl Examples include (meth) acrylates, hexa (meth) acrylates of caprolactone adducts of dipentaerystol hexa (meth) acrylate, and melamine (meth) acrylates. It is preferable that a part of the polymerizable monomer is a polymerizable monomer containing a carboxyl group-containing polyfunctional monomer. For example, pentaerythritol or a derivative thereof may be used.

  As a photopolymerization initiator for generating an active species for initiating a polymerization reaction of a radical polymerizable monomer, tert-butylperoxy-iso-butarate, 2,5-dimethyl-2,5-bis (benzoyldioxy) hexane 1,4-bis [α- (tert-butyldioxy) -iso-propoxy] benzene, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis (tert-butyldioxy) hexene hydroperoxide, α- (Iso-propylphenyl) -iso-propyl hydroperoxide, 2,5-bis (hydroperoxy) -2,5-dimethylhexane, tert-butyl hydroperoxide, 1,1-bis (tert-butyldioxy) -3,3 , 5-trimethylcyclohexane, butyl-4,4-bis (t-butyldioxy) valere -To, cyclohexanone peroxide, 2,2 ', 5,5'-tetra (tert-butylperoxycarbonyl) benzophenone, 3,3', 4,4'-tetra (tert-butylperoxycarbonyl) benzophenone, 3,3 ' , 4,4′-tetra (tert-amylperoxycarbonyl) benzophenone, 3,3 ′, 4,4′-tetra (tert-hexylperoxycarbonyl) benzophenone, 3,3′-bis (tert-butylperoxycarbonyl)- Organic peroxides such as 4,4′-dicarboxybenzophenone, tert-butylperoxybenzoate, t-butyldiperoxyisophthalate, 9,10-anthraquinone, 1-chloroanthraquinone, 2- Quinones such as chloroanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone And benzoin derivatives such as benzoin methyl, benzoin ethyl ether, α-methylbenzoin, α-phenylbenzoin, and the like. Furthermore, as photopolymerization initiators that can be used in the present invention, Irgacure 651, 184, 1173, 907, 369, 379, 819, CGI 124, manufactured by Ciba Specialty Chemicals, TPO manufactured by BASF, Nippon Chemical In addition to Kayacure DTEX manufactured by Yakuhin Co., Ltd., or benzophenones such as 4,4′-diethylaminobenzophenone and 4,4′-dimethylaminobenzophenone, biimidazole compounds and triazine compounds can be exemplified.

  The photosensitive coloring composition contains an organic solvent in order to sufficiently disperse the pigment in the composition and facilitate application on the substrate. Examples of the organic solvent include cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, xylene, ethyl cellosolve, methyl-n amyl ketone, propylene glycol monomethyl ether toluene, Examples include methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, petroleum solvent, and the like. These may be used alone or in combination.

  When dispersing the pigment in the resin, a dispersant such as a surfactant, a resin-type pigment dispersant, and a dye derivative can be appropriately used. Further, additives such as a chain transfer agent, a surfactant, and a silane coupling agent may be added for the purpose of improving applicability, improving sensitivity, and improving adhesion.

  The photosensitive coloring composition of the present invention is produced by mixing each component and finely dispersing it using various dispersing means such as a shaker, a desper, a three-roll mill, a two-roll mill, a sand mill, a kneader, and an attritor. I can do it. The photosensitive coloring composition of the present invention is a coarse particle having a size of 5 μm or more, preferably a coarse particle having a size of 1 μm or more, more preferably a coarse particle having a size of 0.5 μm or more. It is preferable to remove the mixed dust.

  As the transparent substrate, a glass plate such as soda lime glass, low alkali borosilicate glass, non-alkali aluminoborosilicate glass or the like is used. Application of spray coating, spin coating, slit coating, roll coating, etc. on a transparent substrate one by one using the black photosensitive resin and photosensitive coloring composition of the above composition prepared as an alkali development type colored resist material By a method, it apply | coats so that a dry film thickness may be set to 0.5-3 micrometers. If necessary, the dried film is exposed to ultraviolet light through a mask having a predetermined pattern provided in contact with or non-contact with the film. After that, it is immersed in an aqueous alkaline developer such as sodium carbonate or sodium hydroxide, or sprayed with a developer to remove the uncured portion to form a desired pattern to form a black matrix, each color filter segment and A stacked PS is formed. Furthermore, in order to accelerate | stimulate superposition | polymerization of the photosensitive coloring composition and to harden | cure, it heats (post-baking) as needed.

In the color filter substrate according to the present invention, a transparent protective layer may be formed on the colored pixels and the laminated PS portion. For liquid crystals that require electric field driving in the thickness direction of the liquid crystal cell gap with transparent electrodes, such as vertically aligned liquid crystal, liquid crystal called OCB (Optically Compensated Birefringence), ferroelectric liquid crystal, and liquid crystal called ECB (Electrically Controlled Birefringence) A step of forming a transparent conductive film can be added after the step of forming the pixel and the stacked PS and the step of forming the transparent protective layer. In this case, an insulating layer is formed on the transparent electrode on the laminated layer or at a site where the spacer of the counter substrate contacts. This insulating layer may be formed at the same time as the alignment regulating protrusion for the purpose of regulating liquid crystal alignment (alignment control) such as viewing angle and responsiveness improvement. For example, in the case of an IPS (lateral electric field) type liquid crystal display device which does not require a transparent conductive film as a color filter substrate, the insulating layer can be omitted.

  For example, in a VA liquid crystal display device in which liquid crystal is vertically aligned, a transparent electrode is formed in advance on a black matrix, a colored pixel layer, and a laminated PS, and a spacer using a transparent resin is further formed on the transparent electrode. A protrusion for controlling the orientation may be formed.

  As a method for forming the transparent conductive film, vacuum deposition methods called vapor deposition, ion plating, and sputtering are generally used. For the transparent conductive film, a composite oxide of a metal oxide such as indium, tin, gallium, or zinc can be used.

  An embodiment according to the present invention will be described below with reference to FIG. In addition, this invention is not limited to a following example, unless the summary is exceeded. In Examples and Comparative Examples, “parts” and “%” mean “parts by mass” and “% by mass”, respectively.

  Colored pixels of three colors of black matrix, R, G, and B were provided on a 0.7 mm thick glass substrate. In the following Examples and Comparative Examples, in order to clarify the effect of the present invention, a color filter having a laminated portion in which only blue colored compositions having different transparent extender pigment contents were laminated on a black matrix was produced. .

  First, preparation of the acrylic resin solution and the color pigment dispersion used in the examples and comparative examples will be described. The molecular weight of the resin is a weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography).

[Preparation of acrylic resin solution]
A reaction vessel was charged with 370 parts of cyclohexanone, heated to 80 ° C. while injecting nitrogen gas into the vessel, and a mixture of the following monomer and thermal polymerization initiator was added dropwise at the same temperature over 1 hour to carry out the polymerization reaction. .
-20.0 parts of methacrylic acid-10.0 parts of methyl methacrylate-55.0 parts of n-butyl methacrylate-15.0 parts of 2-hydroxyethyl methacrylate-4.0 parts of 2,2'-azobisisobutyronitrile After completion of the reaction, the mixture was further reacted at 80 ° C. for 3 hours. Then, 1.0 part of azobisisobutyronitrile dissolved in 50 parts of cyclohexanone was added, and the reaction was further continued at 80 ° C. for 1 hour. A resin solution was obtained. The mass average molecular weight Mw of this acrylic resin was about 40000. After cooling to room temperature, about 2 g of the resin solution is sampled and heated and dried at 180 ° C. for 20 minutes, and the nonvolatile content is measured. Based on the measurement result, the previously synthesized acrylic resin solution has a nonvolatile content of 30%. Cyclohexanone was added to to prepare an acrylic resin solution.

[Preparation of pigment dispersion]
The mixture having the composition (mass ratio) shown in Table 1 was uniformly stirred and mixed, then dispersed with a sand mill for 5 hours using glass beads having a diameter of 1 mm, and then filtered with a 5 μm filter to obtain a red pigment dispersion PR, A green pigment dispersion PG and a blue pigment dispersion PB were prepared.

The specific contents of the composition in Table 1 are shown below.
PR254: Diketopyrrolopyrrole pigment (CI Pigment Red 254) ("Irga Four Red B-CF" manufactured by Ciba Japan)
PR177: anthraquinone pigment (CI Pigment Red 177) (Chromotar Red A2B manufactured by Ciba Japan)
PG36: Copper halide phthalocyanine pigment (CI Pigment Green 36) (“Rionol Green 6YK” manufactured by Toyo Ink Co., Ltd.)
PB15: 6: ε-type copper phthalocyanine pigment (CI Pigment Blue 15: 6) (“Heliogen Blue L-6700F” manufactured by BASF)
PY150: Nickel azo complex pigment (CI Pigment Yellow 150) ("E4GN" manufactured by LANXESS)
・ Resin type dispersant: “Solsperse 20000” manufactured by Nippon Lubrizol
-Acrylic resin solution: previously prepared acrylic resin solution-Solvent: cyclohexanone [Production of photosensitive coloring composition]
The mixture (mass ratio) shown in Table 2 was stirred and mixed to be uniform, and then filtered through a 1 μm filter to adjust the blue photosensitive coloring compositions of Comparative Example 1 and Examples 1 to 3, respectively. did. In addition, the red and green photosensitive coloring composition was adjusted similarly to the blue photosensitive composition of the comparative example 1, respectively, without including a transparent extender pigment.

The specific contents of the composition in Table 2 are shown below.
Colored pigment dispersion: Blue pigment dispersion PB prepared earlier
-Transparent extender: "Organosilica sol: PMA-ST" manufactured by Nissan Chemical Co., Ltd.
-Post-added resin: Alkali-soluble acrylic resin-Photopolymerizable monomer: "Aronix M402" manufactured by Toa Gosei Co., Ltd.
Photopolymerizable monomer: “US-TD12P”
Photoinitiator: “Irgacure 379” manufactured by Ciba Specialty Chemicals
・ Sensitizer: “EAB-F” manufactured by Hodogaya Chemical Co., Ltd.)
・ Sensitizer: “DAROCUR TPO” manufactured by Ciba Japan
-Surfactant: BYK330 "BYK330" 2% cyclohexanone solution-Organic solvent: PGMAc (propylene glycol monomethyl ether acetate)
・ Organic solvent: EEP (Ethyl-3-ethoxypropionate)
・ Organic solvent: cyclohexanone [colored pixel, spacer formation]
A colored pixel layer was formed using the obtained photosensitive coloring composition. A red colored composition is applied to a glass substrate on which a stripe-shaped resin black matrix having a thickness only 1.8 μm thick and partially widened is formed in advance by spinless coating so that the finished film thickness becomes 2.0 μm. It was applied to. After drying at 90 ° C. for 5 minutes, it is irradiated with 300 mJ / cm ² of light from a high-pressure mercury lamp through a striped photomask for forming a red pixel, developed with an alkaline developer for 60 seconds, and then colored in a striped red color. I got a pixel. Then, it hardened | cured at 230 degreeC for 30 minutes.

  Next, the green coloring composition was similarly applied by spinless coating so that the finished film thickness was 2.0 μm. After drying at 90 ° C. for 5 minutes, green pixels were obtained by exposing and developing through a photomask so that a pattern was formed adjacent to the red pixels. Then, it hardened | cured at 230 degreeC for 30 minutes.

Furthermore, in exactly the same way as red and green, the blue colored composition of Comparative Example 1 which does not contain a transparent extender pigment has a finished film thickness of 2.0 μm as a target, and Examples 1 to 1 containing a transparent extender pigment No. 3 is a film thickness obtained under the same coating conditions as in the comparative example, and a blue pixel at a position adjacent to the red and green colored pixels and a dot-shaped laminated portion having a diameter of 52 μm on the black matrix were obtained. Then, it hardened | cured at 230 degreeC for 30 minutes. As a result, a color filter having a striped colored pixel of three colors of red, green and blue on a transparent substrate and a laminated PS pattern made of a blue composition on a black matrix was obtained.

  The alkaline developer has the following composition.

Sodium carbonate 1.5% by mass
Sodium bicarbonate 0.5% by mass
Anionic surfactant (Kao Perillex NBL) 8.0% by mass
90.0% by mass of water
<Measurement of ride rate>
About the color filter produced using the photosensitive blue composition of Examples 1-3 and the comparative example 1, as shown in FIG. 2, the film thickness (a) of a blue pixel, and the film | membrane of the dot-shaped laminated part on BM The thickness (b) was measured with a contact-type film thickness meter. Moreover, the boarding rate (b / a) was calculated. The results are shown in Table 3.

<Evaluation results>
From the results shown in Table 3, the relationship graph between the total pigment content (Pcon) and the run-up rate is shown in FIG. 3, and the relationship graph between the transparent extender pigment content (Pcon) and the run-up rate is shown in FIG. The main difference in composition between Examples 1 to 3 and Comparative Example 1 is the content of the transparent extender pigment, and as the amount of the transparent extender pigment increases, the tendency to increase the climb rate is seen, as shown in FIG. It was found that there is a substantially linear relationship between the content of the transparent extender pigment and the climbing rate. In addition, the relationship between the riding rates is the same even if the hue changes. For this reason, in the color filter of the present invention, when the color filter of the colored composition formed on the BM portion has a higher running rate compared to the thickness of the pixel flat portion, the colored pixel has a thinner thickness than the conventional one. In addition, it is possible to obtain a necessary PS stacking height with a photosensitive coloring composition having a small number of colors.

1 ... Glass substrate 2 ... Black matrix
3R ... Red pixel 3G ... Green pixel 3B ... Blue pixel
4, 4R, 4G, 4B ... laminated PS 5 ... transparent electrode (ITO film)

Claims (3)

In a color filter substrate having a black matrix on a substrate, colored pixels of a plurality of colors, and a laminated photo spacer formed by laminating one or more photosensitive colored compositions constituting the colored pixels on the black matrix,
A color filter substrate comprising 1 to 30% by mass of a transparent extender pigment in the total solid content of the photosensitive coloring composition. A photosensitive coloring composition used for forming colored pixels and laminated photo spacers of the color filter substrate according to claim 1,
It is a photosensitive coloring composition comprising at least a coloring pigment or dye, a transparent resin, a photopolymerizable monomer, a photopolymerization initiator, a solvent, and a transparent extender pigment, and 1 to 30% by mass of a transparent extender in the total solid content. A photosensitive coloring composition containing a pigment.   The photosensitive coloring composition according to claim 2, wherein the transparent extender pigment is at least one selected from the group consisting of silicon oxide, barium sulfate, aluminum oxide, calcium carbonate, and magnesium carbonate.