CN1963572A - Red staining composition for color filter, color filter and liquid crystal display device - Google Patents

Abstract

A red coloring composition for color filters, comprising a coloring material carrier composed of a transparent resin, its precursor, or a mixture thereof, and a red coloring material. The red coloring material contains at least the following three kinds of pigments, and the average primary particle size of each pigment is 10-50nm. The three kinds of pigments are dioxopyrrolopyrrole red pigments, anthraquinone red pigments and azo yellow pigments . The color filter has red filter segments formed using the red coloring composition for color filters. In addition, the liquid crystal display device has the color filter.

Description

Red coloring composition for color filter, color filter and liquid crystal display device

technical field

The present invention relates to a red coloring composition for color filters used for forming filter segments constituting color filters used in liquid crystal display devices and solid-state imaging devices, and to color filters obtained by using the red coloring composition for color filters , and a liquid crystal display device having the color filter.

Background technique

In recent years, liquid crystal display devices have been evaluated as being space-saving, light-weight, power-saving, etc. due to their thin shape, and their popularity in television applications has recently been rapidly advancing. Liquid crystal display devices for televisions are required to further improve performance such as brightness and contrast, and further improvements in brightness and contrast are also expected in color filters that constitute components of liquid crystal display devices.

Conventionally, C.I. Pigment Red 177, which is an anthraquinone-based red pigment, has been used as a coloring material constituting a red filter segment of a color filter. This pigment can be easily miniaturized by mechanical treatment, and since the miniaturized pigment can be relatively easily dispersed, it contributes to improvement of contrast (for example, refer to Japanese Patent Application Laid-Open No. 10-148712). However, the color filter using this pigment has limitations in improving brightness due to the spectral characteristics of the pigment.

Recently, C.I. Pigment Red 254, which is a dioxopyrrolopyrrole red pigment, is frequently used instead of an anthraquinone red pigment. Compared with C.I. Pigment Red 177, since the transmission spectrum near 600nm is shifted to the short wavelength side, the absorption of the bright red line of the backlight becomes less, so that the brightness can be improved (for example, refer to Japanese Patent Application Laid-Open No. 11-231516 Publication No. 2002-328217). However, although micronization is easy by mechanical treatment, since the cohesive force of the micronized pigment is strong, dispersion becomes difficult as the degree of micronization becomes higher, and it is difficult to improve contrast.

On the other hand, it has been proposed to improve color characteristics by mixing two kinds of red pigments and yellow pigments (the above-mentioned JP-A-10-148712). However, although the combination of these three pigments is effective for expanding the color reproduction area of the color filter, it is not sufficient for high contrast.

Contents of the invention

Therefore, the object of the present invention is to provide a red coloring composition for a color filter capable of forming red filter segments with high brightness and contrast, a color filter having red filter segments with high brightness and contrast, and a color filter having the same. Liquid crystal display device.

According to one aspect of the present invention, there is provided a red coloring composition for a color filter, which contains a coloring material carrier and a red coloring material composed of a transparent resin, a precursor thereof, or a mixture thereof, wherein the above-mentioned red coloring material contains at least The following three kinds of pigments, and the average primary particle size of each pigment is 10-50nm, the three kinds of pigments are dioxopyrrolopyrrole red pigments, anthraquinone red pigments and azo yellow pigments.

According to 2nd aspect of this invention, the color filter provided with the red filter segment formed using the red coloring composition for color filters of this invention is provided.

In addition, according to a third aspect of the present invention, there is provided a liquid crystal display device comprising the color filter of the present invention.

Using the red coloring composition for color filters of the present invention can form a red coloring film, and for this red coloring film, when using the F10 light source to measure the chromaticity of the XYZ chromaticity diagram, the chromaticity y when x is 0.64 is in the range of 0.30-0.35 Within the range, and the brightness Y value is preferably 23 or more. It is preferred that the brightness Y value be as high as possible, and practically the upper limit is around 28.

In addition, in the red coloring composition for color filters of the present invention, it is preferable that the above-mentioned dioxopyrrolopyrrole-based red pigment accounts for 30 to 75% by weight and the anthraquinone-based red pigment accounts for 20% by weight based on the total weight of the above-mentioned three kinds of pigments. -60% by weight, the azo yellow pigment accounts for 5-30% by weight.

Further, it is preferable that the dioxopyrrolopyrrole red pigment is C.I. Pigment Red 254, the anthraquinone red pigment is C.I. Pigment Red 177, and the azo yellow pigment is C.I. Pigment Yellow 150.

The red coloring composition for color filters of this invention can form the red filter segment with high brightness and contrast.

Moreover, by using the color filter of this invention, a liquid crystal display device can be made into high brightness|luminance and high contrast.

Description of drawings

FIG. 1 is a cross-sectional view schematically showing an example of a liquid crystal display device including a color filter of the present invention.

Detailed ways

First, the red coloring composition for color filters of this invention is demonstrated.

The red coloring composition for color filters of the present invention contains a coloring material carrier composed of a transparent resin, its precursor, or a mixture thereof, and a red coloring material, and may contain a dispersion aid, a photopolymerization initiator, a sensitizer, an organic Solvents, leveling agents, etc.

The red pigment contained in the red coloring composition for a color filter of the present invention contains at least three kinds of pigments: a dioxopyrrolopyrrole-based red pigment, an anthraquinone-based red pigment, and an azo-based yellow pigment (hereinafter, these three pigments are referred to as as "three specific pigments").

In the red coloring composition for color filters of the present invention, at least three specific pigments are mixed in order to achieve both high brightness and high contrast. That is, a dioxopyrrolopyrrole-based red pigment that contributes to brightness improvement alone cannot obtain sufficient contrast, so an anthraquinone-based red pigment that contributes to high contrast is used in combination. However, if an anthraquinone-based red pigment is mixed in order to obtain a sufficient contrast, since the absorption of the bright red line of the backlight increases, the luminance decreases. Therefore, in order to maintain high brightness, an azo-based yellow pigment that contributes to high contrast is also mixed.

In the red coloring composition for color filters of the present invention, in addition to the three specific pigments, red pigments such as quinyridones, perylenes, pyranthracene-8,16-dione, azos, and other red pigments, and isoindols Indolines, quinophthalones, anthraquinones and other yellow pigments to adjust chromaticity.

The red coloring composition for color filters of the present invention is preferably used to form a red coloring film using the red coloring composition for color filters of the present invention from the viewpoint of balancing brightness and hue, and the red coloring film is prepared as follows, That is: so that when the chromaticity of the XYZ chromaticity diagram is measured using the F10 light source, the chromaticity y when x is 0.64 is in the range of 0.30-0.35, and the brightness Y value is 23 or more. If the chromaticity y is lower than 0.30, the transmittance decreases, thereby reducing the luminance. On the other hand, if the chromaticity y exceeds 0.35, since the hue shifts toward yellow, high color reproducibility cannot be exhibited. In addition, when the luminance Y value is lower than 23, since the luminance of the liquid crystal display device is lowered, it is not preferable.

In addition, the F10 light source is a typical fluorescent lamp specified by JIS, and has a spectral distribution close to that of a three-wavelength region-emitting fluorescent lamp used in a backlight of an ordinary liquid crystal display device.

As a dioxopyrrolopyrrole red pigment, C.I. Pigment Orange 71, C.I. Pigment Red 254, 255, 264 etc. are mentioned, for example. Among them, C.I. Pigment Red 254 is particularly suitable for use because of its excellent light resistance, heat resistance, transparency, and tinting strength.

Examples of anthraquinone red pigments include C.I. Pigment Red 177, which is preferably used because of its excellent light resistance, heat resistance, transparency, and tinting strength.

Examples of azo yellow pigments include C.I. Pigment Yellow 1, 3, 10, 12, 13, 14, 17, 55, 81, 83, 93, 94, 95, 97, 150, 154, 166, 167, 180 wait. Among them, C.I. Pigment Yellow 150 is particularly suitable for use because of its excellent light resistance, heat resistance, transparency, and tinting strength.

In addition, in the red coloring composition for color filters of the present invention, an azo-based yellow pigment is used for toning, but in general, for color filters, isoindoline pigments such as C.I. Pigment Yellow 139, C.I. Pigment Yellow 138 and other quinophthalone pigments, etc. However, when only these pigments are used, depolarization (de-polarization) due to the particle shape or molecular structure of the pigment is exhibited, which is disadvantageous for high contrast.

In the red coloring composition for color filters of the present invention, it is preferable that the dioxopyrrolopyrrole-based red pigment accounts for 30-75% by weight and the anthraquinone-based red pigment accounts for 20-60% by weight based on the total weight of the above three specific pigments. , azo-based yellow pigments account for 5-30% by weight, in addition, more preferably dioxopyrrolopyrrole-based red pigments account for 35-65% by weight, anthraquinone-based red pigments account for 30-50% by weight, azo-based yellow pigments Accounting for 5-25% by weight. When the ratio of the dioxopyrrolopyrrole red pigment is less than 30% by weight, sufficient brightness cannot be obtained, and when it exceeds 75% by weight, sufficient contrast cannot be obtained. Also, when the proportion of the anthraquinone red pigment is less than 20% by weight, sufficient contrast cannot be obtained, and when it exceeds 60% by weight, sufficient brightness cannot be obtained. In addition, if the proportion of the azo-based yellow pigment is less than 5% by weight, a sufficient brightness-improving effect cannot be exhibited, and if it exceeds 30% by weight, the color reproducibility deteriorates because the color tone is excessively shifted to yellow.

As described above, as the red pigment of the present invention, other pigments may be included in addition to the three specific pigments. The three specific pigments preferably account for 80%-100% of the total weight of the red colorant.

The average primary particle size of the three specific pigments contained in the red coloring composition for color filters of the present invention must be in the range of 10 to 50 nm in order to achieve higher brightness and higher contrast of the color filter. The average primary particle size of the pigment can be measured by observation with a transmission electron microscope. When the average primary particle size of the three specific pigments is larger than 50 nm, the brightness and contrast of the color filter are reduced, and when it is smaller than 10 nm, it is very difficult to disperse the pigments, and it is difficult to ensure the fluidity of the coloring composition. As a result, the brightness and contrast of the color filter deteriorate.

Needless to say, when the red pigment contained in the red coloring composition for color filters of this invention contains other pigments besides the three specific pigments, it is preferable that other pigments have an average primary particle diameter of 10-50 nm.

As means for reducing the primary particle size of pigments, there are methods of mechanically pulverizing pigments (called grinding method), and methods of depositing pigments dissolved in a good solvent into a poor solvent and then depositing pigments with a desired primary particle size (called grinding method). Precipitation method) and a method of producing a pigment with a desired primary particle size during pigment synthesis (called synthetic precipitation method), etc. It can be carried out by selecting an appropriate method for each pigment according to the synthesis method, chemical properties, etc. of the pigment used. Each method will be described below.

The grinding method is to use a ball mill, a sand mill or a kneader to mechanically mix the pigment with an abrasive such as sodium chloride and a water-soluble inorganic salt and a water-soluble organic solvent that does not dissolve the abrasive (hereinafter referred to as a salt mill). (salt milling)), the grinding agent and the organic solvent are washed away, and dried to obtain the required specific surface area of the pigment. However, the crystal growth of the pigment may occur through the salt milling treatment. Therefore, adding at least a part of the dissolved solid resin or a dispersing aid described later to the above water-soluble organic solvent can effectively prevent the crystal growth.

With regard to the ratio of the pigment and the abrasive (water-soluble inorganic salt), if the ratio of the abrasive is large, the micronization efficiency of the pigment increases, but the throughput of the pigment decreases, so the productivity decreases. Generally, 1 to 30 parts by weight of the abrasive can be used with respect to 1 part by weight of the pigment, preferably 2 to 20 parts by weight of the abrasive.

In addition, the water-soluble organic solvent is a substance added to make the pigment and the abrasive (water-soluble inorganic salt) into a uniform mass. Although it also depends on the ratio of the pigment and the abrasive, it is usually 50-300% of the pigment. % by weight is used.

Further, the salt grinding method will be described in detail. A small amount of water-soluble organic solvent is added as a wetting agent to a mixture of pigment and grinding agent (water-soluble inorganic salt), and after intensive kneading with a kneader or the like, the mixture is poured into water and used Agitate with a high-speed mixer or the like to make a slurry. Next, the slurry is filtered, washed with water, and then dried to obtain a pigment having a desired primary particle size.

The precipitation method is to dissolve the pigment in an appropriate good solvent and mix it with a poor solvent to precipitate the pigment with the required primary particle size. The primary particle size can be controlled by the type or amount of the solvent, the precipitation temperature, and the precipitation speed. . In general, since the pigment is difficult to dissolve in the solvent, the solvents that can be used are limited. For example, strong acidic solvents such as concentrated sulfuric acid, polyphosphoric acid, and chlorosulfonic acid are known, or liquid ammonia, dimethylformamide of sodium methoxide, etc. alkaline solvents, etc.

A representative example of the precipitation method is an acid pasting method in which a solution in which a pigment is dissolved in an acidic solvent is poured into another solvent and re-precipitated to obtain fine particles. Industrially, from the viewpoint of cost, a method of injecting a sulfuric acid solution into water is generally used. The sulfuric acid concentration is not particularly limited, but is preferably 95 to 100% by weight. The amount of sulfuric acid used with respect to the pigment is not particularly limited, but when the amount of sulfuric acid is small, the viscosity of the solution becomes high and handling properties deteriorate. Conversely, when the amount of sulfuric acid is too large, the processing efficiency of the pigment decreases. Therefore, it is preferable to use 3-10 weight part of sulfuric acid with respect to 1 part of pigments. Also, it is not necessary for the pigment to dissolve completely. The temperature at which the pigment is dissolved is preferably 0 to 50°C. At a temperature lower than 0°C, sulfuric acid may freeze and the solubility may also decrease. When the temperature at which the pigment dissolves is too high, it is easy to cause side reactions. The temperature of the water into which the sulfuric acid is injected is preferably 1 to 60°C. If the injection is started at a temperature exceeding 60°C, it will boil due to the heat of dissolution of the sulfuric acid, and the operation is dangerous. Additionally, the solution freezes at temperatures below 1 °C. The time taken for the injection is preferably 0.1 to 30 minutes with respect to 1 part of the pigment.

By choosing a combination of precipitation methods such as acid paste method and grinding methods such as salt grinding method, the primary particle size of the pigment can be controlled while considering the degree of sizing of the pigment, and the fluidity of the obtained pigment can also be ensured, so it is more is preferred.

When performing salt milling or acid paste, in order to prevent the aggregation of the pigment accompanying the control of the primary particle size, dispersing aids such as pigment derivatives, resin-type dispersants, and surfactants, which will be described later, can also be used in combination. In addition, by controlling the primary particle size in the form of coexistence of two or more pigments, even pigments that are difficult to disperse individually can be processed as stable dispersions.

The synthetic precipitation method is a method of precipitating a pigment having a desired primary particle diameter simultaneously with synthesizing the pigment. However, when the generated fine pigments are taken out from the solvent, if the pigment particles do not aggregate and become large secondary particles, it is difficult to carry out filtration as a normal separation method, so this method is generally suitable for use in areas where secondary aggregation is prone to occur. Azo and other pigments synthesized in the water system.

In addition, as a means of controlling the primary particle size of the pigment, it is also possible to disperse the pigment for a long time using a high-speed sand mill (the so-called dry grinding method of dry pulverizing the pigment), so that the primary particle size of the pigment can be reduced. to disperse.

The coloring material carrier contained in the red coloring composition for color filters of this invention disperses the red pigment containing three specific pigments, and consists of a transparent resin, its precursor, or their mixture. The transparent resin is a resin having a transmittance of 80% or more, preferably 95% or more, in the entire wavelength region of 400 to 700 nm in the visible light region. Transparent resins include thermoplastic resins, thermosetting resins, and active energy ray-curable resins, and their precursors include monomers or oligomers that are cured by irradiation with active energy rays to form transparent resins. These can be used alone or in combination. or more uses.

The content of the colorant carrier is 30-700 parts by weight, preferably 60-450 parts by weight, relative to 100 parts by weight of the total amount of red colorant in the coloring composition. In addition, when a mixture of a transparent resin and its precursor is used as a coloring material carrier, the content of the transparent resin may be 20-400 parts by weight relative to 100 parts by weight of the total amount of red coloring material in the coloring composition, preferably 50-250 parts by weight. In addition, the content of the precursor of the transparent resin may be 10-300 parts by weight, preferably 10-200 parts by weight, relative to 100 parts by weight of the total amount of the red coloring material in the coloring composition.

Examples of thermoplastic resins include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, Polyurethane resin, polyester resin, acrylic resin, alkyd resin, polystyrene, polyamide resin, rubber resin, cyclized rubber resin, cellulose, polyethylene, polybutadiene, polyimide resin etc. In addition, examples of thermosetting resins include epoxy resins, benzoguanamine resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, melamine resins, urea resins, and phenolic resins.

As the active energy ray-curable resin, a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, or an amino group and a (meth)acrylic compound having a reactive substituent such as an isocyanate group, an aldehyde group, or an epoxy group can be used. Alternatively, cinnamic acid is reacted to introduce photocrosslinkable groups such as (meth)acryloyl groups and styryl groups into the linear polymer resin. In addition, it is also possible to use (meth)acrylic compounds containing styrene-maleic anhydride copolymers, α-olefin-maleic anhydride copolymers, etc. A substance obtained by half-esterifying a polymer.

Examples of monomers and oligomers that are cured by active energy ray irradiation to form transparent resins include methyl (meth)acrylate, ethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-Hydroxypropyl (meth)acrylate, cyclohexyl (meth)acrylate, β-carboxyethyl (meth)acrylate, diethylene glycol di(meth)acrylate, 1,6-hexanedi Alcohol di(meth)acrylate, Triethylene glycol di(meth)acrylate, Tripropylene glycol di(meth)acrylate, Trimethylolpropane tri(meth)acrylate, Pentaerythritol tri(meth)acrylate Acrylates, 1,6-hexanediol diglycidyl ether di(meth)acrylate, bisphenol A diglycidyl ether di(meth)acrylate, neopentyl glycol diglycidyl ether di(meth)acrylate Acrylates, dipentaerythritol hexa(meth)acrylate, tricyclodecanyl (meth)acrylate, (meth)acrylate of methylolated melamine, epoxy (meth)acrylate, urethane acrylate Various acrylates and methacrylates, (meth)acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth)propylene Amide, N-methylol(meth)acrylamide, N-vinylformamide, acrylonitrile, etc. These substances may be used alone or in combination of two or more.

In the red coloring composition for color filters of the present invention, when the composition is cured by ultraviolet irradiation, a photopolymerization initiator or the like may be added.

As the photopolymerization initiator, 4-phenoxydichloroacetophenone, 4-tert-butyl-dichloroacetophenone, diethoxyacetophenone, 1-(4-isopropylphenyl) -2-Hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinephenyl)-butane- Acetophenone compounds such as 1-ketone, benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin dimethyl ketal, etc. , benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4' -Methyl diphenyl sulfite, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone and other benzophenone compounds, thioxanthone, 2-chlorosulfur Thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-diethylthioxanthone and other thioxanthones Compounds, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)- 4,6-bis(trichloromethyl)-s-triazine, 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-(naphtho-1-yl)-4 , 6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl-(piperonyl)-6-triazine, 2,4-trichloromethyl-(4'-methoxystyryl)-6-triazine and other triazine compounds, 1,2-octanedione, 1-[4-(thiophenyl)-2-(O-benzoyl oxime)], O-(acetyl)-N-(1-phenyl-2-oxo -2-(4'-methoxy-naphthyl)ethylene)hydroxylamine and other oxime ester compounds, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4, Phosphine compounds such as 6-trimethylbenzoyldiphenylphosphine oxide, quinone compounds such as 9,10-phenanthrenequinone, camphorquinone, ethylanthraquinone, borate ester compounds, carbazole compounds, imidazoles compounds, titanocene compounds, etc. These photopolymerization initiators can be used 1 type or in mixture of 2 or more types. The content of the photopolymerization initiator is 5 to 200 parts by weight, preferably 10 to 150 parts by weight, relative to 100 parts by weight of the total amount of the red pigment.

The above-mentioned photopolymerization initiators may be used alone or in combination of two or more, or may be used in combination with a sensitizer. Examples of the sensitizer include triethanolamine, methyldiethanolamine, triisopropanolamine, 4-dimethyl Aminobenzoic acid methyl ester, 4-dimethylaminobenzoic acid ethyl ester, 4-dimethylaminobenzoic acid isopentyl ester, benzoic acid 2-dimethylaminoethyl ester, 4-dimethylaminobenzoic acid 2- Ethylhexyl ester, N,N-dimethyl-p-toluidine, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, Amine compounds such as 4,4'-bis(ethylmethylamino)benzophenone. These sensitizers can be used 1 type or in mixture of 2 or more types. Content of a sensitizer can be 0.1-60 weight part with respect to 100 weight part of photoinitiators.

The red coloring composition for color filters of this invention may further contain the polyfunctional mercaptan which functions as a chain transfer agent. The polyfunctional thiol should be any compound as long as it has 2 or more thiol groups, for example, hexanedithiol, decanedithiol, 1,4-butanediol dithiopropionate, 1 , 4-Butanediol Dithioglycolate, Ethylene Glycol Dithioglycolate, Ethylene Glycol Dithiopropionate, Trimethylolpropane Trithioglycolate, Trimethylolpropane Trithiopropionate, Trimethylolpropane Tris(3-Mercaptobutyrate), Pentaerythritol Tetrathioglycolate, Pentaerythritol Tetrathiopropionate, Tris(2-Hydroxyethyl) Trimercaptopropionate Isocyanurate, 1,4-dimethylmercaptobenzene, 2,4,6-trimercapto-s-triazine, 2-(N,N-dibutylamino)-4,6-dimercapto- s-triazine etc. These polyfunctional thiols may be used alone or in combination of two or more. The content of the polyfunctional thiol may be 0.05-100 parts by weight, preferably 0.1-60 parts by weight, relative to 100 parts by weight of the total amount of the red coloring material.

In the red coloring composition for a color filter of the present invention, in order to sufficiently disperse the red coloring material (various pigments) in the coloring material carrier, and apply it on a glass substrate so that the dry film thickness becomes 0.2 to 5 μm, further May contain solvents. Examples of solvents 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-pentanone, propylene glycol monomethyl ether toluene, methyl ethyl ketone, ethyl acetate, methanol, ethanol, iso Propanol, butanol, isobutyl ketone, petroleum solvents, etc. These solvents may be used alone or in combination. The content of the solvent may be 800 to 4000 parts by weight, preferably 1000 to 2500 parts by weight, relative to 100 parts by weight of the total amount of the red coloring material.

The red coloring composition for color filters can be produced by finely grinding red colorants (various pigments) using various dispersing means such as three-roll mills, two-roll mills, sand mills, kneaders, and attritors. Dispersed in the colorant carrier. In addition, in order to disperse the red coloring material well, dispersion aids such as pigment derivatives, resin-type pigment dispersants, and surfactants may be appropriately contained. Dispersion aids have excellent pigment dispersibility and have a large effect of preventing re-aggregation of dispersed pigments. Therefore, when using a coloring composition formed by dispersing pigments in a colorant carrier and a solvent using a dispersing aid, transparent Excellent color filter. The content of the dispersing aid may be 0.1-40 parts by weight, preferably 0.1-30 parts by weight, relative to 100 parts by weight of the total amount of the red colorant.

In addition to being used as a dispersing aid, the pigment derivative has an effect of suppressing crystal growth or aggregation of the pigment in the filter segment. The term "dye derivative" refers to a compound having a substituent introduced into an organic dye. Examples of organic dyes include dioxopyrrolopyrroles, azos such as azo, disazo, and polyazo, phthalocyanines, anthraquinones, quinacridones, dioxazines, and perylenes. Ketones, perylenes, thioindigos, isoindolines, isoindolinones, quinophthalones, shilin, metal complexes and other pigments. Organic pigments constituting pigment derivatives also include light yellow compounds such as naphthalenes and triazines, which are generally not called pigments.

Examples of the substituent introduced into the organic dye include substituents represented by the following general formulas (1) to (4).

Formula (1)

Formula (2)

Formula (3)

Formula (4)

In general formula (1)～(4),

X represents -SO ₂ -, -CO-, -CH ₂ NHCOCH ₂ -, -CH ₂ - or a single bond,

n represents the integer of 1-10.

R ₁ and R ₂ each independently represent an alkyl group that may be substituted with 1-36 carbon atoms, an alkenyl group that may be substituted with 2-36 carbon atoms, or a phenyl group that may be substituted, or R ₁ and R ₂ combine with each other to form a heterocyclic residue that further contains nitrogen, oxygen or sulfur atoms and may be substituted.

R ₃ represents an alkyl group that may be substituted with 1-36 carbon atoms, an alkenyl group that may be substituted with 2-36 carbon atoms, or a phenyl group that may be substituted,

R ₄ , R ₅ , R ₆ and R ₇ each independently represent a hydrogen atom, an alkyl group with 1-36 carbon atoms that may be substituted, an alkenyl group with 2-36 carbon atoms that may be substituted or Substituted phenyl,

Y represents -NR ₈ -Z-NR ₉ - or a single bond,

R ₈ and R ₉ each independently represent a hydrogen atom, an alkyl group with 1-36 carbon atoms that may be substituted, an alkenyl group with 2-36 carbon atoms that may be substituted or a phenyl group that may be substituted,

Z represents an optionally substituted alkylene group with 1-36 carbon atoms, an optionally substituted alkenylene group with 2-36 carbon atoms, or an optionally substituted phenylene group,

R represents a substituent represented by the following formula (5) or a substituent represented by the following formula (6),

Q represents a hydroxyl group, an alkoxy group, a substituent represented by the following formula (5), or a substituent represented by the following formula (6). In addition, in the following formula (5) or formula (6), X, R ₁ -R ₇ , and n are as defined above.

Formula (5)

Formula (6)

These pigment derivatives may be used alone or in combination of two or more. The content of the pigment derivative is preferably 5 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the total amount of the red pigment. If it is less than the lower limit, the effect of inhibiting the crystal growth of the pigment or aggregation may be reduced, and if it exceeds the upper limit, the fluidity of the obtained red coloring composition may not be maintained.

As resin-type pigment dispersants, condensates of ricinoleic acid and 12-hydroxystearic acid, basic polymer compounds, acid group-containing copolymers, fatty acid esters, and aliphatic polyamine/polyester grafts can be used. polymers, polyethylene/polypropylene addition polymers, etc.

Examples of surfactants include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzenesulfonate, alkali salt of styrene-acrylic acid copolymer, sodium alkylnaphthalenesulfonate, alkyl diphenyl ether disulfide, Sodium sulfonate, monoethanolamine lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene Anionic surfactants such as alkyl ether phosphates; polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphates, polyoxyethylene sorbitan Nonionic surfactants such as monostearate and diethylene glycol monolauryl ester; cationic surfactants such as alkyl quaternary ammonium salts and their oxyethylene adducts; alkyl dimethylaminoacetate betaine Amphoteric surfactants such as alkyl betaines, alkyl imidazolines, etc. These surfactants can be used alone or in combination of two or more.

In the red coloring composition for color filters of the present invention, a storage stabilizer may be contained in order to stabilize the viscosity of the composition over time, and a silane coupling agent, etc. may be contained in order to improve the adhesiveness with a transparent substrate. Adhesion enhancer. As storage stabilizers, for example, quaternary ammonium chloride salts such as benzyl trimethyl chloride and diethylhydroxylamine, organic acids such as lactic acid and oxalic acid and their methyl ethers, tert-butylcatechol, tetraethyl Phosphine, tetraphenylphosphine and other organic phosphines, phosphites, etc.

Examples of the silane coupling agent include vinyl silanes such as vinyltris(β-methoxyethoxy)silane, vinylethoxysilane, vinyltrimethoxysilane, γ-methacryloyl (Meth)acrylic silanes such as oxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, β-(3,4-epoxycyclohexyl) Methyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltriethoxysilane, β-(3,4-epoxycyclohexyl)methyltriethoxysilane, γ -Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane and other epoxysilanes, N-β-(aminoethyl)-γ-aminopropyltrimethoxy N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane, γ-ammonia Propyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltriethoxysilane and other amino groups Silanes, thiosilanes such as γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane, etc.

The red coloring composition can be prepared in the form of a gravure offset printing ink, an anhydrous offset printing ink, a screen printing ink, or a solvent-developed or alkaline-developed colored resist. The colored resist is obtained by dispersing the above three pigments in a composition containing a thermoplastic resin, a thermosetting resin, or an active energy ray curable resin, a monomer, a photopolymerization initiator, and a solvent. The three specific pigments are preferably contained in a ratio of 5 to 70% by weight based on the total solid content of the red composition (100% by weight). It is more preferably contained in a ratio of 20 to 50% by weight, and the remainder actually comes from the resinous binder provided by the coloring material carrier.

For the red coloring composition, it is preferable to obtain coarse particles of 5 μm or more, preferably 1 μm or more coarse particles, more preferably 0.5 μm or more coarse particles, and even more preferably 0.2 μm or more, by centrifugal separation, sintering filter, membrane filter and other means. Particle and entrained dust removal.

The color filter of this invention has the red filter segment formed using the red coloring composition for color filters of this invention on a transparent substrate. The color filter of the present invention generally further has green filter segments and blue filter segments formed using a known coloring composition.

As a transparent substrate, glass plates such as soda-lime glass, low-alkali borosilicate glass, and alkali-free aluminoborosilicate glass, and resin plates such as polycarbonate, polymethyl methacrylate, and polyethylene terephthalate can be used. . In addition, transparent electrodes made of indium oxide, tin oxide, etc. may be formed on the surface of a glass plate or a resin plate for liquid crystal drive after liquid crystal panelization.

Formation of the filter segments of each color can be performed by, for example, a printing method, a photolithography method, or the like.

The formation of filter segments of each color by the printing method can form a pattern only by repeating the printing and drying of the coloring composition prepared as the above-mentioned various printing inks, so it is a low-cost manufacturing method for color filters. Furthermore, it is excellent in mass productivity. Also, with the development of printing technology, it is possible to print fine patterns with high dimensional accuracy and smoothness. For printing, it is preferable to have a composition in which the ink does not dry or cure on the printing plate or blanket. In addition, it is also important to control the fluidity of the ink on the printing press, and it is possible to adjust the viscosity of the ink using a dispersant or an extender pigment.

When forming filter segments of various colors by photolithography, spray coating, spin coating, slit coating, roll coating, etc. on a transparent substrate can be used as the above-mentioned solvent-developing or alkaline-developing colored resist. And the prepared coloring composition is coated so that a dry film thickness may become 0.2-10 micrometers. When drying the coating film, a reduced-pressure dryer, a convection dryer, an IR dryer, a hot plate, or the like can also be used. The dried film is exposed to ultraviolet light through a mask having a predetermined pattern placed in contact or non-contact with the film as needed. Thereafter, the uncured portion is removed by immersing in a solvent or an alkaline developer or spraying the developer with a sprayer to form a desired pattern, and then the same operation is repeated for other colors to manufacture a color filter. Furthermore, in order to accelerate the polymerization of a colored resist, heating may be performed as needed. Using photolithography, it is possible to manufacture a color filter with higher precision than the printing method described above.

When developing the colored composition, aqueous solutions such as sodium carbonate and sodium hydroxide are used as alkaline developing solutions, and organic bases such as dimethylbenzylamine and triethanolamine can also be used. In addition, an antifoaming agent or surfactant may also be added to the developer. As a method of developing treatment, a shower developing method, a spray developing method, a soaking (immersion) developing method, a Puddle developing method, etc. can be used. In addition, in order to improve the sensitivity to ultraviolet light exposure, after coating and drying the above-mentioned colored resist, coating and drying a water-soluble or alkaline water-soluble resin, such as polyvinyl alcohol or water-soluble acrylic resin, etc., can prevent polymerization caused by oxygen. After barrier film, UV exposure is performed.

The color filter of the present invention can be produced by an electrodeposition method, a transfer method, or the like in addition to the above-mentioned methods. In addition, the electrodeposition method is to use a transparent conductive film formed on a transparent substrate to electrodeposit and form filter segments of various colors on the transparent conductive film through electrophoresis of colloidal particles, thereby manufacturing a color filter.

In addition, the transfer method is a method of preliminarily forming filter segments on the surface of a peelable transfer base sheet or a transfer body, and then transferring the filter segments to a desired transparent substrate.

Before forming the filter segments of each color on the transparent substrate or the reflective substrate, if the black matrix is formed in advance, the contrast of the liquid crystal display panel can be further improved. As the black matrix, a multilayer film of chromium and chromium/chromium oxide, an inorganic film such as titanium nitride, or a resin film in which a light-shielding agent is dispersed can also be used. In addition, thin film transistors (TFTs) may also be formed in advance on the above-mentioned transparent substrate or reflective substrate, and then the filter section is formed. By forming the filter section on the TFT substrate, the aperture ratio of the liquid crystal display panel can be increased and the brightness can be improved.

On the filter of the present invention, an overcoat film or columnar spacer, a transparent conductive film, a liquid crystal alignment film, and the like may be formed as necessary.

Next, a liquid crystal display device having the color filter of the present invention will be described.

FIG. 1 is a schematic cross-sectional view of a liquid crystal display device including a color filter of the present invention. The device 10 shown in FIG. 1 is a typical example of a TFT-driven liquid crystal display device for a notebook computer, and includes a pair of transparent substrates 11 and 21 arranged opposite to each other, and a liquid crystal (LC) is sealed between them. Liquid crystals (LC) are aligned according to drive modes such as TN (Twisted Nematic), STN (Super Twisted Nematic), IPS (Lateral Electric Field Effect), VA (Vertical Alignment), OCB (Optically Compensated Bend Alignment).

A TFT (Thin Film Transistor) array 12 is formed on the inner surface of the first transparent substrate 11, and a transparent electrode layer 13 made of, for example, ITO is formed thereon. An alignment layer 14 is provided on the transparent electrode layer 13 . In addition, a polarizing plate 15 is formed on the outer surface of the transparent substrate 11 .

On the other hand, the color filter 22 of the present invention is formed on the inner surface of the second transparent substrate 21 . The red, green, and blue filter segments constituting the color filter 22 are separated by a black matrix (not shown). The color filter 22 is covered, and a transparent protective film (not shown) is formed if necessary, and a transparent electrode layer 23 made of, for example, ITO is formed thereon, and an alignment layer 24 is provided covering the transparent electrode layer 23 . In addition, a polarizing plate 25 is formed on the outer surface of the transparent substrate 21 . In addition, a backlight unit 30 including a three-wavelength lamp 31 is provided below the polarizer 15 .

Example

Hereinafter, the present invention will be described more specifically by listing examples and comparative examples, but the present invention is not limited by the following examples. In addition, "part" and "%" in an Example represent "weight part" and "weight%", respectively. In addition, the symbol of the pigment indicates the chromaticity index, for example, "PR254" indicates "C.I. Pigment Red 254", and "PY150" indicates "C.I. Pigment Yellow 150".

In addition, in the following examples, various physical properties were measured by the following methods.

<Measuring methods of various physical properties>

【Average primary particle size of pigment】

Using a transmission electron microscope ("JEM-1200EX" manufactured by JEOL Ltd.), the primary particle diameter of the entire pigment particle in the observation sample was measured at 50,000 magnification, and the average value thereof was taken as the average primary particle diameter. In addition, when the particle shape is not spherical, the major axis and the minor axis are measured, and the value obtained by (major axis+short axis)/2 is regarded as the particle diameter.

[Chroma and Contrast]

The red coloring composition was coated on a glass substrate by spin coating so that the chromaticity x after curing was 0.64 (F10 light source), dried at 70° C. for 20 minutes, and then exposed to ultraviolet light using an ultra-high pressure mercury lamp. Then, this substrate was heat-processed at 230 degreeC for 1 hour, and the red colored film was obtained. For this red colored film, the chromaticity (Y, x, y) under the F10 light source was measured using a microspectrophotometer ("OSP-SP100" manufactured by Olympus Optical Co., Ltd.). In addition, polarizers were laminated on both sides of the substrate on which the red colored film was formed, and the ratio of the brightness (Lp) when the polarizers were parallel to the brightness (Lc) when the polarizers were perpendicular, Lp/Lc, was calculated as contrast. Brightness was measured under a 2° field of view condition using a color luminance meter (“BM-5A” manufactured by Topcon Corporation).

In addition, dye derivatives D-1 to D-3 used in the following production examples are shown below.

Manufacture of micronized pigments

Manufacturing example 1

100 parts of dioxopyrrolopyrrole red pigment PR254 ("IRGAPHOR RED B-CF" produced by Ciba Specialty Chemicals), 10 parts of pigment derivative (D-1), 1000 parts of pulverized sodium chloride, and diethyl 120 parts of diols were put into a 1-gallon kneader made of stainless steel (manufactured by Inoue Seisakusho), and kneaded at 60° C. for 10 hours. Put this mixture into 2,000 parts of warm water, heat it to about 80°C, and stir it with a high-speed mixer for about 1 hour to form a slurry. After repeated filtration and water washing to remove sodium chloride and solvent, dry at 80°C. After 24 hours, a micronized pigment (R-1) was obtained. The average particle diameter of the obtained pigment was 25 nm.

Manufacturing example 2

Put 100 parts of anthraquinone red pigment PR177 ("CROMOPHTAL RED A2B" produced by Ciba Specialty Chemicals), 8 parts of pigment derivative (D-2), 700 parts of crushed sodium chloride, and 180 parts of diethylene glycol Kneading was carried out at 70° C. for 4 hours in a 1-gallon kneader made of stainless steel (manufactured by Inoue Seisakusho). Put this mixture into 4000 parts of warm water, heat it to about 80°C, and stir it with a high-speed mixer for about 1 hour to form a slurry. After repeated filtration and water washing to remove sodium chloride and solvent, dry at 80°C for 24 hours, a micronized pigment (R-2) was obtained. The average particle diameter of the obtained pigment was 30 nm.

Manufacturing example 3

Put 100 parts of perylene-based red pigment PR179 ("Pariogen Malone L-3920" produced by Baier Corporation), 8 parts of pigment derivative (D-2), 1000 parts of pulverized sodium chloride, and 120 parts of diethylene glycol into stainless steel In a 1-gallon kneader (manufactured by Inoue Seisakusho), knead at 60°C for 8 hours. Put this mixture into 2000 parts of warm water, heat to about 80°C, and stir for about 1 hour using a high-speed mixer , formed a slurry, repeated filtration, washing to remove sodium chloride and solvent, and dried at 80° C. for 24 hours to obtain a micronized pigment (R-3). The average particle diameter of the obtained pigment was 35 nm.

Manufacturing example 4

Put 100 parts of quinophthalone yellow pigment PY138 ("PALIOTOLYELLOW K0961HD" produced by BASF company), 5 parts of pigment derivative (D-3), 750 parts of crushed sodium chloride, and 180 parts of diethylene glycol into a stainless steel In a 1-gallon kneader (manufactured by Inoue Seisakusho), kneading was carried out at 60° C. for 6 hours. Put this mixture into 3000 parts of warm water, heat it to about 80°C, and stir it with a high-speed mixer for about 1 hour to form a slurry. After repeated filtration and water washing to remove sodium chloride and solvent, dry at 80°C for 24 hours, a micronized pigment (Y-1) was obtained. The average particle diameter of the obtained pigment was 40 nm.

<Manufacture of acrylic resin solution>

Add 370 parts of cyclohexanone to the reaction container, heat it to 80°C while injecting nitrogen into the container, and add the following substances dropwise at the same temperature for 1 hour to carry out polymerization reaction: 20.0 parts of methacrylic acid, methyl methacrylate A mixture of 10.0 parts, 55.0 parts of n-butyl methacrylate, 15.0 parts of 2-hydroxyethyl methacrylate, and 4.0 parts of 2,2'-azobisisobutyronitrile. After the dropwise addition, it was further reacted at 80°C for 3 hours, then a solution in which 1.0 parts of azobisisobutyronitrile was dissolved in 50 parts of cyclohexanone was added, and the reaction was continued at 80°C for 1 hour to obtain an acrylic resin solution. The weight average molecular weight of the acrylic resin is about 40,000. After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180°C for 20 minutes, and the non-volatile components were measured. Based on the measurement results, cyclohexanone was added so that the non-volatile components in the previously synthesized resin solution reached 20 % by weight to prepare an acrylic resin solution.

<Manufacture of pigment dispersion>

After the mixture of the composition shown in Table 1 was uniformly stirred and mixed, it was dispersed for 3 hours with a sand mill (Aiga-Mil) ("Minimodel M-250 MKII" produced by Aiga-Jiapan Co., Ltd.) using zirconia beads with a diameter of 1 mm. , and then filtered through a 5 μm filter membrane to obtain various pigment dispersions. Table 1 also records the pigment content in each pigment dispersion at the same time.

Table 1

Pigment Dispersion pigment Pigment derivatives Mixed composition (parts) Pigment content pigment Pigment derivatives Acrylic resin solution Cyclohexanone total RP-1 R-1 D-1 10.8 1.2 40.0 48.0 100.0 PR254 9.8% RP-2 R-2 D-2 11.2 0.8 40.0 48.0 100.0 PR177 10.4% RP-3 R-3 D-2 10.8 1.2 40.0 48.0 100.0 PR179 10.0% RP-4 R-4 D-1 10.8 1.2 40.0 48.0 100.0 PR254 10.8% RP-5 R-5 D-2 11.0 1.0 40.0 48.0 100.0 PR177 11.0%   YP-1 Y-1 D-3 10.8 1.2 40.0 48.0 100.0 PY138 10.3%   YP-2 Y-2 D-3 10.8 1.2 40.0 48.0 100.0 PY150 10.8%

Note)

R-4: PR254 ("IRGAPHOR RED B-CF" produced by Ciba Specialty Chemicals; average primary particle size: 70nm)

R-5: PR177 ("CROMOPHTAL RED A2B" produced by Ciba Specialty Chemicals; average primary particle size: 80nm)

Y-2: PY150 ("E4GN-GT" manufactured by Lankuses Corporation; average primary particle size: 40nm)

<Preparation of red coloring composition>

Example 1

Evenly stir and mix 21.2 parts of pigment dispersion (RP-1), 20.1 parts of pigment dispersion (RP-2), 9.7 parts of pigment dispersion (YP-2), 1.0 parts of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-1). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Example 2

Evenly stir and mix 25.2 parts of pigment dispersion (RP-1), 21.0 parts of pigment dispersion (RP-2), 4.8 parts of pigment dispersion (YP-2), 1.0 parts of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-2). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Example 3

Evenly stir and mix 21.2 parts of pigment dispersion (RP-1), 26.0 parts of pigment dispersion (RP-2), 3.8 parts of pigment dispersion (YP-2), 1.0 parts of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-3). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Comparative example 1

Evenly stir and mix the pigment dispersion pigment dispersion (RP-2) 20.2 parts, pigment dispersion (RP-3) 21.0 parts, pigment dispersion (YP-2) 9.8 parts, acrylic resin solution 1.0 parts, trimethylolpropane 4.0 parts of triacrylate ("NK ester ATMPT" manufactured by Shin-Nakamura Chemical Co., Ltd.), 3.4 parts of photopolymerization initiator ("Irugakia 907" manufactured by Ciba Specialty Chemicals Co., Ltd.), sensitizer ("EAB-F" manufactured by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were then filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-4). Table 2 shows the mixing ratios of various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Comparative example 2

Evenly stir and mix 24.0 parts of pigment dispersion (RP-4), 22.0 parts of pigment dispersion (RP-2), 5.0 parts of pigment dispersion (YP-2), 1.0 parts of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-5). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Comparative example 3

Evenly stir and mix 25.9 parts of pigment dispersion (RP-1), 20.2 parts of pigment dispersion (RP-5), 4.9 parts of pigment dispersion (YP-2), 1.0 part of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-6). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Comparative example 4

Evenly stir and mix 25.2 parts of pigment dispersion (RP-1), 20.8 parts of pigment dispersion (RP-2), 5.0 parts of pigment dispersion (YP-1), 1.0 parts of acrylic resin solution, trimethylolpropane triacrylate ("NK ester ATMPT" produced by Shin Nakamura Chemical Co., Ltd.) 4.0 parts, a photopolymerization initiator ("Irugaki 907" produced by Ciba Specialty Chemicals Co., Ltd.) 3.4 parts, a sensitizer ("EAB-F" produced by Hodo Keya Chemical Co., Ltd.) 0.4 parts and 40.2 parts of cyclohexanone were filtered through a 1 μm filter to obtain 100 parts of a red coloring composition (RR-7). Table 2 shows the mixing ratios of the various pigments in the obtained red coloring composition. In addition, Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition on a glass substrate.

Table 2

red coloring composition Mixing composition of pigment dispersion (parts)                             PR254 PR177 PR179 PY150 PY138 Example 1 RR-1 RP-1 RP-2 YP-2 40% 40% --- 20% --- 21.2 20.1 9.7 Example 2 RR-2 RP-1 RP-2 YP-2 48% 42% --- 10% --- 25.2 21.0 4.8 Example 3 RR-3 RP-1 RP-2 YP-2 40% 52% --- 8% --- 21.2 26.0 3.8 Comparative example 1 RR-4 RP-2 RP-3 YP-2 --- 40% 40% 20% --- 20.2 21.0 9.8 Comparative example 2 RR-5 RP-4 RP-2 YP-2 48% 42% --- 10% --- 24.0 22.0 5.0 Comparative example 3 RR-6 RP-1 RP-5 YP-2 48% 42% --- 10% --- 25.9 20.2 4.9 Comparative example 4 RR-7 RP-1 RP-2 YP-1 48% 42% --- --- 10% 25.2 20.8 5.0

table 3

Chroma Contrast ratio Y x y Example 1 24.5 0.64 0.33 2600 Example 2 24.3 0.64 0.33 2800 Example 3 23.8 0.64 0.32 3000 Comparative example 1 21.2 0.64 0.31 2400 Comparative example 2 24.3 0.64 0.33 900 Comparative example 3 24.0 0.64 0.33 1200 Comparative example 4 24.5 0.64 0.32 1400

As shown in Table 3, in the red coloring films formed using the coloring compositions of Examples 1-3 of the present invention, the chromaticity y when x is 0.64 is in the range of 0.30-0.35, and the brightness Y value is 23 or more . In addition, the contrast ratio also reaches high values.

On the other hand, in the red colored film formed using the colored composition of Comparative Example 1, the brightness Y value was significantly lower than 23. It is considered that the use of PR179, whose transmission spectrum near 600nm is shifted to the long wavelength side compared with PR254, was used instead of PR254, and the red bright line absorption of the backlight became larger. In addition, in the red colored film of Comparative Example 2-4, the contrast was a low value. It is considered to be due to the use of red pigments whose average primary particle diameter exceeds the upper limit (50 nm) of the range specified in the present invention in Comparative Examples 2 and 3, and the use of PY138 as a yellow pigment in Comparative Example 4, so that the respective depolarization effects become smaller. Obviously, the contrast becomes a lower value.

Claims (7)

1. color filter red colored composition, it contains colouring matter carrier and the red colored material of being made up of transparent resin, its precursor or their potpourri, it is characterized in that, described red colored material contains following three kinds of pigment at least, and the average primary particle diameter of each pigment is 10-50nm, and described three kinds of pigment are diketopyrrolopyrroles class red pigment, anthraquinone class red pigment and azo class yellow uitramarine.

2. according to the color filter red colored composition of claim 1 record, it is characterized in that, use described color filter to form red colored film with red colored composition, when using the F10 light source to come the colourity of measured X YZ chromatic diagram to this red colored film, x be 0.64 o'clock chromaticity y in the scope of 0.30-0.35 and brightness Y value be more than 23.

3. according to the color filter red colored composition of claim 1 record, it is characterized in that, general assembly (TW) with respect to described three kinds of pigment, described diketopyrrolopyrroles class red pigment accounts for 30-75 weight %, anthraquinone class red pigment accounts for 20-60 weight %, and azo class yellow uitramarine accounts for 5-30 weight %.

4. according to the color filter red colored composition of claim 1 record, it is characterized in that, described diketopyrrolopyrroles class red pigment is a C.I. paratonere 254, and described anthraquinone class red pigment is a C.I. paratonere 177, and described azo class yellow uitramarine is a C.I. pigment yellow 150.

5. according to the color filter red colored composition of claim 1 record, it is characterized in that,, contain described colouring matter carrier with the ratio of 30-700 weight portion with respect to the total amount of the described red colored material of 100 weight portions.

6. color filter is characterized in that, the red filter joint that it color filter that possesses any one record of use claim 1-5 forms with red colored composition.

7. liquid crystal indicator is characterized in that, it possesses the color filter of claim 6 record.