KR20070050366A - Red-colored composition for color filters, color filter, and liquid crystal display device - Google Patents

Abstract

The red coloring composition for color filters contains the coloring material carrier which consists of a transparent resin, its precursor, or a mixture thereof, and a red coloring material. A red coloring agent contains at least 3 types of pigments of a diketopyrrolopyrrole red pigment, an anthraquinone type red pigment, and an azo yellow pigment, and the average primary particle diameter of each pigment is 10-50 nm. The color filter has a red filter segment formed by using the red coloring composition for the color filter. In addition, the liquid crystal display device is provided with this color filter.

Color filter, red, coloring composition, transparent resin, diketopyrrolopyrrole, pigment, anthraquinone, azo, yellow.

Description

RED-COLORED COMPOSITION FOR COLOR FILTERS, COLOR FILTER, AND LIQUID CRYSTAL DISPLAY DEVICE}

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

The present invention provides a red color composition for color filters used in the formation of filter segments constituting color filters used in liquid crystal display devices and solid-state image pickup devices, a color filter obtained by using the red color composition for color filters, and the same. It relates to a liquid crystal display device.

BACKGROUND ART Liquid crystal display devices have recently been evaluated for their ultra-thin, space-saving, lightweight, power-saving, and the like. BACKGROUND ART Liquid crystal display devices for televisions are required to further improve performances such as brightness and contrast, and even higher color brightness, higher contrast, and the like are desired for color filters which are members constituting the liquid crystal display device.

Conventionally, C. I. Pigment Red 177 which is an anthraquinone type red pigment has been used for the coloring material of the red filter segment which comprises a color filter. Since this pigment can be easily refined by a mechanical treatment and the finely pigmented can be dispersed relatively easily, it is useful for increasing the contrast (for example, Japanese Patent Laid-Open No. 10-148712). Reference). However, the color filter using this pigment has a limit in the improvement of the brightness because of the spectral characteristics which this pigment has.

In recent years, C. I. Pigment Red 254 which is a diketopyrrolopyrrole red pigment is used instead of the anthraquinone type red pigment. Since the pigment has a transmission spectrum near 600 nm shifted to the shorter wavelength side than CI Pigment Red 177, since the absorption of the red bright line of the backlight becomes less, the brightness can be improved (for example, Japanese Patent Laid-Open No. 11-13). 231516, Japanese Patent Application Laid-Open No. 2002-328217). However, although the refinement by mechanical treatment is easy, since the finer pigment has a strong cohesive force, it becomes difficult to disperse | distribute as refinement degree becomes high and it is not easy to improve contrast.

On the other hand, it is proposed to improve a color characteristic by mix | blending two types of red pigments and a yellow pigment (the said Unexamined-Japanese-Patent No. 10-148712). However, the combination of these three pigments is effective for widening the color reproduction area of the color filter, but it is insufficient for high contrast.

Accordingly, the present invention provides a red colorant composition for a color filter capable of forming a red filter segment having high brightness and contrast, a color filter having a red filter segment having high brightness and contrast, and a liquid crystal display device having the same. The purpose.

According to one aspect of the present invention, there is provided a red coloring composition f for a color filter containing a transparent carrier, a precursor thereof or a mixture thereof, and a red coloring agent, wherein the red coloring agent is a diketopyrrolopyrrole red pigment, At least three pigments of an anthraquinone-based red pigment and an azo-based yellow pigment are provided, and a red colored composition for a color filter is provided, wherein the average primary particle diameter of each pigment is 10 to 50 nm.

According to a second aspect of the present invention, there is provided a color filter comprising a red filter segment formed by using the red coloring composition for color filters of the present invention.

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.

The red coloring composition for color filters of this invention forms the red coloring film using this, and chromaticity y when x is 0.64 when the chromaticity of an XYZ colorimeter is measured about this red coloring film using a F10 light source is used. It is preferable to exist in the range of 0.30 to 0.35, and to have a brightness Y value of 23 or more. The brightness Y value is preferably as high as possible, but in reality, about 28 is the upper limit.

Moreover, in the red coloring composition for color filters of this invention, the said diketopyrrolopyrrole red pigment occupies 30-75 weight% with respect to the total weight of the said 3 types of pigments, and the anthraquinone type red pigment is 20-60. It is preferable to occupy weight% and 5 to 30 weight% of azo yellow pigments.

In addition, the diketopyrrolopyrrole-based red pigment is C. I. Pigment Red 254, the anthraquinone-based red pigment, C. I. Pigment Red 177, it is preferred that the azo yellow pigment is C. I. Pigment Yellow 150.

(The best form to carry out invention)

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 carrier composed of a transparent resin, a precursor thereof or a mixture thereof, and a red coloring agent, and a dispersion aid, a photopolymerization initiator, a sensitizer, an organic solvent, a leveling agent and the like, as necessary. It contains.

The red coloring agent contained in the red coloring composition for color filters of the present invention comprises three pigments of diketopyrrolopyrrole-based red pigment, anthraquinone-based red pigment, and azo-based yellow pigment (hereinafter, these three kinds of pigments, And " three kinds of specific pigments "

In the red coloring composition for color filters of this invention, at least 3 types of specific pigments are mix | blended in order to make high brightness and high contrast compatible. That is, since sufficient contrast is not obtained only by using diketopyrrolopyrrole red pigment which is advantageous for improving brightness alone, an anthraquinone red pigment which is advantageous for high contrast is used in combination. However, when anthraquinone type red pigment is mix | blended in order to acquire sufficient contrast, since the absorption of the red bright line of a backlight increases, the brightness falls. Therefore, in order to maintain high brightness, the azo type yellow pigment which is advantageous for high contrast is further mix | blended.

The red coloring composition for color filters of the present invention, in addition to three specific pigments, for adjusting the chromaticity, red pigments such as quinacridone series, perylene series, pyrantrone series, azo series, isoindolin series, Yellow pigments, such as nophthalone system and anthraquinone system, can be contained.

The red colored composition for color filters of the present invention forms a red colored film using the red colored composition for color filters of the present invention in terms of the balance between brightness and color, and uses the F10 light source for the red colored film. When the chromaticity of a colorimetric system is measured, it is preferable to prepare so that chromaticity y when x may be 0.64 exists in the range of 0.30-0.35, and brightness Y value may be 23 or more. If the chromaticity y is less than 0.30, the transmittance is lowered and the brightness is lowered. On the other hand, when chromaticity y exceeds 0.35, since the color shifts to yellow, display with high color reproduction cannot be performed. Moreover, when the brightness Y value is less than 23, since the brightness | luminance of a liquid crystal display device is reduced, it is unpreferable.

In addition, the F10 light source is a typical fluorescent lamp of JIS standard, and has a spectral distribution close to that of a three wavelength region light emitting fluorescent lamp used for a backlight of a general liquid crystal display device.

As a dikenopyrrolopyrrole 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 suitably used because of its excellent light resistance, heat resistance, transparency and coloring power.

As an anthraquinone type red pigment, C. I. Pigment Red 177 is mentioned, for example, It is used suitably for the outstanding light resistance, heat resistance, transparency, and coloring power.

As an azo yellow pigment, for example, CI Pigment Yellow 1, 3, 10, 12, 13, 14, 17, 55, 81, 83, 93, 94, 95, 97, 150, 154, 166, 167, 180 Etc. can be mentioned. Among them, C. I. Pigment Yellow 150 is particularly suitably used because of its excellent light resistance, heat resistance, transparency and coloring power.

In addition, in the red coloring composition for color filters of the present invention, azo-based yellow pigments are used for toning, but in general, in color filter applications, isoindolin-based pigments such as CI Pigment Yellow 139 and quinopels such as CI Pigment Yellow 138 Talon pigments and the like are often used. However, when only these pigments are used, since de-polarization due to the particle shape or molecular structure of the pigment is expressed, it is disadvantageous for high contrast.

In the red coloring composition for color filters of the present invention, the diketopyrrolopyrrole red pigment accounts for 30 to 75% by weight, and the anthraquinone red pigment is 20 to 60% by weight based on the total weight of the three specific pigments. It is preferred that the azo yellow pigment accounts for 5 to 30% by weight, the diketopyrrolopyrrole red pigment accounts for 35 to 65% by weight, and the anthraquinone red pigment accounts for 30 to 50% by weight. More preferably, the azo yellow pigment accounts for 5 to 25% by weight. When the ratio of the diketopyrrolopyrrole 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. Moreover, even when the ratio of anthraquinone type red pigment is less than 20 weight%, sufficient contrast cannot be obtained, and when it exceeds 60 weight%, sufficient brightness cannot be obtained. In addition, when the ratio of the azo-based yellow pigment is less than 5% by weight, a sufficient brightness enhancement effect does not appear. When the ratio of the azo-based yellow pigment is more than 30% by weight, the color shifts excessively to yellow, resulting in poor color reproduction.

As described above, the red colorant of the present invention may contain other pigments in addition to the three specific pigments. It is preferable that three specific pigments occupy 80%-100% of the total weight of a red coloring material.

The three specific pigments contained in the red coloring composition for color filters of the present invention should have an average primary particle diameter in the range of 10 to 50 nm in order to realize high brightness and high contrast of the color filter. The average primary particle diameter of the pigment can be measured by transmission electron microscope observation. When the average primary particle diameter of the three specific pigments is larger than 50 nm, the brightness and contrast of the color filter are lowered, and when smaller than 10 nm, pigment dispersion is very difficult, and it becomes difficult to secure fluidity as a colored composition. . As a result, the brightness and contrast of the color filter deteriorate.

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

As means for reducing the primary particle diameter of the pigment, a method of mechanically crushing the pigment (called a grinding method), or a method of depositing a pigment having a desired primary particle diameter by adding a pigment dissolved in a good solvent into a poor solvent (precipitation) Method), and a method for producing a pigment having a desired primary particle diameter in the synthesis of the pigment (called a synthetic precipitation method). According to the synthesis | combining method, chemical property, etc. of the pigment to be used, an appropriate method can be selected and performed with respect to each pigment. Each method is demonstrated below.

In the grinding method, the pigment is mechanically kneaded using a ball mill, a sand mill or a kneader together with a grinding agent such as a water-soluble inorganic salt such as sodium chloride and a water-soluble organic solvent that does not dissolve the grinding agent (hereinafter, After salt milling, the grinding | polishing agent and the organic solvent are washed with water, and it is a method of obtaining the pigment of a desired specific surface area by drying. However, since a pigment may crystal grow by a salt milling process, it is effective to add the solid resin which melt | dissolves at least in part in the said water-soluble organic solvent at the time of a process, and the dispersion aid mentioned later, and prevent crystal growth.

About the ratio of a pigment and a grinding | polishing agent (water-soluble inorganic salt), when the ratio of a grinding | polishing agent increases, the refinement | miniaturization efficiency of a pigment will improve but productivity will fall because the throughput of a pigment becomes small. Generally, it is preferable to use 1-30 weight part of grinding | pulverization agents, preferably 2-20 weight part with respect to 1 weight part of pigments.

In addition, the water-soluble organic solvent is added so that the pigment and the grinding agent (water-soluble inorganic salt) become a uniform lump, and depending on the blending ratio of the pigment and the grinding agent, it is usually in an amount equivalent to 50 to 300% by weight of the pigment. Used.

The grinding method will be described in more detail. A small amount of a water-soluble organic solvent is added to the mixture of the pigment and the grinding agent (aqueous inorganic salt) as a humectant, kneaded with a kneader or the like, and then the mixture is put in water and the high speed Stir with a mixer or the like to obtain a slurry. Next, the slurry of the desired primary particle diameter can be obtained by filtering, washing with water, and drying this slurry.

The precipitation method is a method of dissolving a pigment in a suitable good solvent, mixing it with a poor solvent, and precipitating a pigment having a desired primary particle diameter. The size of the primary particle diameter is determined by the type and amount of solvent, precipitation temperature, and precipitation rate. Can be controlled. In general, since the pigment is difficult to dissolve in a solvent, the solvent that can be used is limited, for example, a strong acid solvent such as concentrated sulfuric acid, polyphosphoric acid, chlorosulfonic acid, or a basic solution such as a liquid ammonia or a dimethylformamide solution of sodium methylate. Solvents and the like are known.

As a representative example of the precipitation method, there 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 precipitated again to obtain fine particles. Industrially, the method of injecting sulfuric acid solution into water is common from a cost point of view. Although sulfuric acid concentration is not specifically limited, 95-100 weight% is preferable. Although the usage-amount of sulfuric acid with respect to a pigment is not specifically limited, When the quantity of sulfuric acid is small, the viscosity of the solution obtained will become high and handling property will worsen. On the contrary, when the amount of sulfuric acid is too large, the treatment efficiency of the pigment is reduced. Therefore, it is preferable to use 3-10 weight part of sulfuric acid with respect to 1 part of pigments. In addition, the pigment does not need to be completely dissolved. As for the temperature at the time of melt | dissolution of a pigment, 0-50 degreeC is preferable, At the temperature below 0 degreeC, sulfuric acid may be frozen and solubility also becomes low. When the temperature at the time of dissolution of the pigment is too high, side reactions are likely to occur. The temperature of the water into which sulfuric acid is injected is preferably 1 to 60 ° C., and if the injection is started at a temperature exceeding 60 ° C., boiling is caused by the heat of dissolution of sulfuric acid, which is dangerous. At temperatures below 1 ° C, the solution freezes. The time taken for the injection is preferably 0.1 to 30 minutes with respect to 1 part of the pigment.

The control of the primary particle diameter of the pigment can be carried out by selecting a method combining a precipitation method such as an acid pasting method and a grinding method such as a salt milling method. It is more preferable because it can be secured.

At the time of salt milling or acid pasting, dispersing aids such as a pigment derivative, a resinous dispersant, and a surfactant described below may be used in combination to prevent agglomeration of the pigment associated with primary particle diameter control. Moreover, even if it is a pigment which is difficult to disperse alone, it can be completed as a stable dispersion by carrying out the form which made two or more types of pigments coexist with primary particle diameter control.

The synthetic precipitation method is a method of synthesizing a pigment and simultaneously depositing a pigment having a desired primary particle diameter. However, in the case of taking out the produced micronized pigment in a solvent, filtration, which is a general separation method, becomes difficult unless the pigment particles are agglomerated and become large secondary particles. Therefore, this method is usually synthesized in an aqueous system where secondary aggregation is likely to occur. It is applied to pigments, such as an azo system.

Further, as a means for controlling the primary particle diameter of the pigment, the pigment is dispersed for a long time by a high-speed sand mill or the like (so-called dry milling method for dry grinding the pigment), thereby reducing the primary particle diameter of the pigment and simultaneously dispersing the pigment. It is also possible.

The coloring material carrier contained in the red coloring composition for color filters of this invention disperse | distributes the red coloring material containing three specific pigments, and is comprised by transparent resin, its precursor, or its 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. The transparent resin includes a thermoplastic resin, a thermosetting resin, and an active energy ray-curable resin, and the precursor includes monomers or oligomers that are cured by active energy ray irradiation to produce a transparent resin, and these alone or in combination thereof. It can mix and use the above.

The colorant carrier can be used in an amount of 30 to 700 parts by weight, preferably 60 to 450 parts by weight, based on 100 parts by weight of the total red colorant in the coloring composition. In the case where a mixture of the transparent resin and its precursor is used as the colorant carrier, the transparent resin is 20 to 400 parts by weight, preferably 50 to 250 parts by weight based on 100 parts by weight of the total amount of the red colorant in the coloring composition. Can be used as The precursor of the transparent resin can be used in an amount of 10 to 300 parts by weight, preferably 10 to 200 parts by weight, based on 100 parts by weight of the total amount of the red colorant in the colored composition.

Examples of the thermoplastic resin 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 and the like. Moreover, as a thermosetting resin, an epoxy resin, benzoguanamine resin, rosin modified maleic acid resin, rosin modified fumaric acid resin, melamine resin, urea resin, a phenol resin etc. are mentioned, for example.

As active energy ray curable resin, (meth) acrylic compound and silicic acid which have reactive substituents, such as an isocyanate group, an aldehyde group, an epoxy group, and silicic acid are made to react with the linear polymer which has reactive substituents, such as a hydroxyl group, a carboxyl group, and an amino group, Resin which introduce | transduced photocrosslinkable groups, such as a diary and a styryl group, into this linear polymer can be used. Moreover, the linear polymer containing acid anhydrides, such as a styrene-maleic anhydride copolymer and the (alpha)-olefin-maleic anhydride copolymer, is made half by the (meth) acryl compound which has hydroxyl groups, such as hydroxyalkyl (meth) acrylate. The esterified thing can also be used.

As a monomer and oligomer which harden | cure by active energy ray irradiation and produce a transparent resin, methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl ( Meta) acrylate, cyclohexyl (meth) acrylate, β-carboxyethyl (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, triethylene glycol di (Meth) acrylate, tripropylene glycol di (meth) acrylate, trimetholpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, Bisphenol A diglycidyl ether di (meth) acrylate, neopentylglycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) Various acrylic esters, such as an acrylate, the (meth) acrylic acid ester of metharolized melamine, epoxy (meth) acrylate, urethane acrylate, and methacrylic acid ester, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl Ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-vinylformamide, acrylonitrile, etc. are mentioned. These can be used individually or in mixture of 2 or more types.

A photoinitiator etc. are added to the red coloring composition for color filters of this invention when hardening this composition by ultraviolet irradiation.

As a photoinitiator, 4-phenoxydichloroacetophenone, 4-t-butyl- dichloroacetophenone, diethoxy acetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl propane-1-one Acetophenone compounds such as 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, benzoin methyl ether, Benzoin compounds such as benzoin ethyl ether, benzoin isopropyl ether, benzyl dimethyl ketal, benzophenone, benzoyl benzoic acid, benzoyl benzoate methyl, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4 Benzophenone compounds such as '-methyldiphenyl sulfide, 3,3', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, thioxanthone, 2-chlorothioxanthone, 2- Thioxanthone type compounds, such as methyl thioxanthone, isopropyl thioxanthone, 2, 4- diisopropyl thioxanthone, and 2, 4- diethyl thioxanthone, 2,4, 6- trichloro-s-tri Azine, 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-trichloro Triazine compounds such as methyl (4'-methoxystyryl) -6-triazine, 1,2-octanedione, 1- [4- (phenylthio) phenyl]-, 2- (0-benzoyloxime), Oxime ester compounds, such as O- (acetyl) -N- (1-phenyl-2-oxo-2- (4'-methoxy-naphthyl) ethylidene) hydroxyamine, bis (2,4,6- Phosphine compounds such as trimethylbenzoyl) phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 9,10- I Transistor quinone, camphor quinone, the quinone compounds, borate compounds, carbazole-based compounds, imidazole-based compound, a titanocene compound such as metallocene, such as ethyl anthraquinone, is used. These photoinitiators can be used 1 type or in mixture of 2 or more types. A photoinitiator can be used in the quantity of 5-200 weight part, Preferably it is 10-150 weight part with respect to a total of 100 weight part of a red coloring material.

Said photoinitiator is used individually or in mixture of 2 or more types, or as a sensitizer, a triethanolamine, a methyl diethanolamine, a triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, and 4-dimethylaminobenzoic acid Isoamyl, 2-dimethylaminoethyl benzoate, 2-ethylhexyl 4-dimethylaminobenzoic acid, N, N-dimethylparatoluidine, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (di Amine compounds, such as ethylamino) benzophenone and 4,4'-bis (ethylmethylamino) benzophenone, can also be used together. These sensitizers can be used 1 type or in mixture of 2 or more types. A sensitizer can be used in the quantity of 0.1-60 weight part with respect to 100 weight part of photoinitiators.

The red coloring composition for color filters of this invention can further contain the polyfunctional thiol which functions as a chain transfer agent. The polyfunctional thiol may be a compound having two or more thiol groups, for example, hexanedithiol, decandithiol, 1,4-butanediolbisthiopropionate, 1,4-butanediolbisthioglycolate, ethylene glycol Bisthioglycolate, ethylene glycol bisthiopropionate, trimetholpropane tristhioglycolate, trimetholpropane tristyopiothionate, trimetholpropane tris (3-mercaptobutyrate), pentaerythritol tetrakis Thioglycolate, pentaerythritol tetraquistiopionate, trimercaptopropionic acid tris (2-hydroxyethyl) isocyanurate, 1,4-dimethyl mercaptobenzene, 2, 4, 6-trimercapto- s-triazine, 2- (N, N-dibutylamino) -4,6-dimercapto-s-triazine, and the like. These polyfunctional thiols can be used 1 type or in mixture of 2 or more types. As for content of a polyfunctional thiol, 0.05-100 weight part is preferable with respect to a total of 100 weight part of red coloring materials, Preferably it can be used in the quantity of 0.1-60 weight part.

The red coloring composition for color filters of this invention can use a solvent in order to disperse | distribute a red coloring agent (various pigment) fully in a coloring carrier and to apply | coat so that a dry film thickness may be set to 0.2-5 micrometers on a glass substrate. As a solvent, for example, 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, methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, petroleum solvents, and the like. These are used individually or in mixture. The solvent can be used in an amount of 800 to 4000 parts by weight, preferably 1000 to 2500 parts by weight, based on 100 parts by weight in total of the red colorant.

The red coloring composition for color filters can be produced by finely dispersing a red colorant (various pigments) on a colorant carrier using various dispersing means such as a three roll mill, a two roll mill, a sand mill, a kneader, and an attritor. . Moreover, in order to make dispersion of a red coloring material favorable, dispersion adjuvant, such as a pigment derivative, a resin pigment dispersant, and surfactant, can be contained suitably. The dispersing aid is excellent in dispersing the pigment and has a great effect of preventing re-agglomeration of the pigment after dispersing. Therefore, when the dispersing aid is used to disperse the pigment in the colorant carrier and the solvent, it is excellent in transparency. A color filter is obtained. The dispersing aid can be used in an amount of 0.1 to 40 parts by weight, preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the total red colorant.

In addition to acting as a dispersing aid, the dye derivative has an effect of suppressing crystal growth or aggregation of the pigment in the filter segment. A dye derivative is a compound which introduced the substituent into the organic pigment | dye. As an organic pigment | dye, For example, azo type, such as diketopyrrolopyrrole type | system | group, azo, disazo, polyazo, phthalocyanine type, anthraquinone type, quinacridone type, dioxazine type, perinone type, perylene type, thio indigo type, And dyes such as isoindolin, isoindolinone, quinophthalone, tren, and metal complex. The organic pigment | dye which comprises a pigment | dye derivative also contains pale yellow compounds, such as naphthalene system and triazine system which are not generally called dye.

As a substituent introduce | transduced into an organic pigment, the substituent represented by following General formula (1)-(4) is mentioned.

In formulas (1) to (4), X represents -SO _2- , -CO-, -CH ₂ NHCOCH _2- , -CH ₂ -or a direct bond,

n represents an integer of 1 to 10,

R ₁ and R ₂ each independently represent an alkyl group which may be substituted with 1 to 36 carbon atoms, an alkenyl group which may be substituted with 2 to 36 carbon atoms, or a phenyl group which may be substituted, or R ₁ and R ₂ are mutually A heterocyclic moiety which may be substituted to further contain a nitrogen, oxygen or sulfur atom,

R <_3> represents the C1-C36 alkyl group which may be substituted, the C2-C36 substituted alkenyl group, or the phenyl group which may be substituted,

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

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

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

Z represents an alkylene group which may be substituted with 1 to 36 carbon atoms, an alkenylene group which may be substituted with 2 to 36 carbon atoms, or a phenylene group which may be substituted,

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 alkoxyl group, a substituent represented by the following formula (5) or a substituent represented by the following formula (6) Indicates. In addition, in following formula (5) and formula (6), X, R <_1> -R <_7> and n are as defined above.

These pigment derivatives can be used individually or in mixture of 2 or more types. The dye derivative is preferably used in an amount of 5 to 40 parts by weight, preferably 10 to 30 parts by weight with respect to 100 parts by weight in total of the red colorant. Below this lower limit, the effect of suppressing the crystal growth or aggregation of the pigment becomes small. If the upper limit is exceeded, there is a possibility that the fluidity of the red colored composition obtained cannot be maintained.

Examples of the resinous pigment dispersant include condensates of ricinolic acid and 12-hydroxystearic acid, basic polymer compounds, copolymers containing acid groups, fatty acid esters, aliphatic polyamine / polyester graft polymers, polyethylene / polypropylene addition polymers, and the like. Can be used.

As surfactant, polyoxyethylene alkyl ether sulfate, sodium dodecyl benzene sulfonate, the alkali salt of a styrene-acrylic acid copolymer, sodium alkylnaphthalin sulfonate, sodium alkyl diphenyl ether disulfonate, lauryl sulfate monoethanolamine, lauryl sulfate Anionic surfactants such as triethanolamine, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, and polyoxyethylene alkyl ether phosphate ester; Nonionic surfactants such as polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphate ester, polyoxyethylene sorbitan monostearate, diethylene glycol monolaurate ; Cationic surfactants such as alkyl quaternary ammonium salts and ethylene oxide adducts thereof; Amphoteric surfactants, such as alkylbetaine, such as alkyldimethylamino acetate betaine, and alkyl imidazoline, These can be used individually or in mixture of 2 or more types.

The red coloring composition for color filters of this invention can contain a storage stabilizer in order to stabilize the viscosity with time, and can also contain adhesive improvement agents, such as a silane coupling agent, in order to improve adhesiveness with a transparent substrate. Examples of storage stabilizers include quaternary ammonium chlorides such as benzyltrimethyl chloride and diethylhydroxyamine, organic acids such as lactic acid and oxalic acid, and methyl ethers thereof, t-butyl pyrocatechol, tetraethylphosphine and tetraphenylphosphate. Organic phosphines, phosphites, such as pin, etc. are mentioned.

As a silane coupling agent, (meth), such as vinyl silanes, such as a vinyl tris ((beta) -methoxyethoxy) silane, a vinyl ethoxysilane, and a vinyl trimethoxysilane, (gamma) -methacryloxypropyl trimethoxysilane, ) Acrylsilane, (beta)-(3, 4- epoxycyclohexyl) ethyltrimethoxysilane, (beta)-(3, 4- epoxycyclohexyl) methyl trimethoxysilane, (beta)-(3, 4- epoxycyclohexyl) Epoxysilanes, such as ethyl triethoxysilane, (beta)-(3, 4- epoxycyclohexyl) methyl triethoxysilane, (gamma)-glycidoxy propyl trimethoxy silane, and (gamma)-glycidoxy propyl triethoxysilane , N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldiethoxysilane, γ -Aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyl Aminosilanes, such as a triethoxysilane, Thiosilanes, such as (gamma)-mercaptopropyl trimethoxy silane and (gamma)-mercaptopropyl triethoxysilane, etc. are mentioned.

The red coloring composition may be prepared in the form of a gravure offset printing ink, anhydrous offset printing ink, silkscreen printing ink, a solvent developing type or an alkali developing type coloring resist. A coloring resist disperse | distributes the said 3 types of pigment in the composition containing a thermoplastic resin, a thermosetting resin, or active energy ray curable resin, a monomer, a photoinitiator, and a solvent. It is preferable that three specific pigments are contained in the ratio of 5-70 weight% in total based on the total solid content of a coloring composition (100 weight%). More preferably, it is contained in the ratio of 20-50 weight%, and the remainder consists essentially of the resinous binder provided by the coloring material carrier.

The red colored composition is 5 micrometers or more coarse particles, preferably 1 micrometers or more coarse particles, more preferably 0.5 micrometers or more coarse particles, and more preferably 0.2 micrometers or more by means of centrifugation, a sintering filter, a membrane filter, or the like. It is preferable to remove the particles and the mixed dust.

The color filter of the present invention includes a red filter segment formed on the transparent substrate using the red color composition for color filter of the present invention. The color filter of the present invention usually further includes a green filter segment and a blue filter segment formed by using a known coloring composition.

As the transparent substrate, glass plates such as soda lime glass, low alkali borosilicate glass, alkali free alumino borosilicate glass, and resin plates such as polycarbonate, polymethyl methacrylate and polyethylene terephthalate are used. Moreover, the transparent electrode which consists of indium oxide, a tin oxide, etc. may be formed in the surface of a glass plate or a resin plate for liquid crystal drive after liquid crystal panelization.

Formation of each color filter segment can be performed by the printing method, the photolithography method, etc., for example.

Since the formation of each color filter segment by the printing method can be patterned only by repeating the printing and drying of the colored composition prepared as the above-mentioned various printing inks, the color filter manufacturing method is low cost and is excellent in mass productivity. Do. In addition, with the development of printing technology, it is possible to print fine patterns having high dimensional accuracy and smoothness. In order to perform printing, it is preferable to set it as the composition which ink does not dry and solidify on a printing plate or a blanket. Moreover, control of the fluidity | liquidity of the ink on a printing press is also important, and ink viscosity by a dispersing agent and a extender pigment can also be adjusted.

In the case of forming each color filter segment by the port lithography method, a coating composition prepared as the solvent developing or alkali developing coloring resist is coated on a transparent substrate such as spray coating, spin coating, slit coating, roll coating or the like. It apply | coats so that dry film thickness may be set to 0.2-10 micrometers. When drying a coating film, you may use a vacuum dryer, a convection oven, an IR oven, a hotplate, etc. The film dried as needed is subjected to ultraviolet exposure through a mask having a predetermined pattern provided in contact or non-contact state with the film. Thereafter, the developer can be immersed in a solvent or an alkaline developer or sprayed with a spray or the like to remove the uncured portion to form a desired pattern, and then the same operation can be repeated for other colors to produce a color filter. Moreover, in order to accelerate superposition | polymerization of a coloring resist, you may heat as needed. According to the photolithography method, a color filter with higher precision than the printing method can be manufactured.

At the time of image development of a coloring composition, aqueous solution, such as sodium carbonate and sodium hydroxide, is used as alkaline developing solution, Organic alkali, such as dimethylbenzylamine and triethanolamine, can also be used. Moreover, an antifoamer and surfactant can also be added to a developing solution. As the development treatment method, a shower development method, a spray development method, a dipping development method, a paddle (liquid film formation) development method, or the like can be applied. In addition, in order to increase the UV exposure sensitivity, after coating and drying the colored resist, a water-soluble or alkali water-soluble resin such as polyvinyl alcohol or a water-soluble acrylic resin is applied and dried to form a film to prevent polymerization inhibition by oxygen. After that, ultraviolet light exposure may be 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 method. In addition, the electrodeposition method is a method of manufacturing a color filter by electrodepositing each color filter segment on the transparent conductive film by electrophoresis of colloidal particles using the transparent conductive film formed on the transparent substrate.

The transfer method is a method in which filter segments are formed in advance on the surface of a peelable transfer base sheet or transfer body, and the filter segments are transferred onto a desired transparent substrate.

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

On the color filter of this invention, an overcoat film, columnar spacer, a transparent conductive film, a liquid crystal aligning film, etc. are formed as needed.

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

1 is a schematic cross-sectional view of a liquid crystal display device having 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 disposed to face each other, and between them, Liquid crystal LC is enclosed. The liquid crystal LC is oriented according to driving modes such as twisted nematic (TN), super twisted nematic (STN), in-plane switching (IPS), vertical alignment (VA), and optically compensated fringefringence (OCB).

On the inner surface of the first transparent substrate 11, a TFT (Thin Film Transistor) array 12 is formed, and a transparent electrode layer 13 made of, for example, ITO is formed thereon. The 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, on the inner surface of the second transparent substrate 21, the color filter 22 of the present invention is formed. The red, green and blue filter segments constituting the color filter 22 are separated by a black matrix (not shown). A transparent protective film (not shown) is formed over the color filter 22 as necessary, and a transparent electrode layer 23 made of, for example, ITO is formed thereon, and covers the transparent electrode layer 23 to form an alignment layer ( 24) is installed. In addition, a polarizing plate 25 is formed on the outer surface of the transparent substrate 21. In addition, the backlight unit 30 provided with the three wavelength lamp 31 is provided below the polarizing plate 15.

(Example)

Although an Example and a comparative example are given to the following and this invention is demonstrated to it further more concretely, this invention is not limited to a following example. In addition, "part" and "%" in an Example represent "weight part" and "weight%", respectively. In addition, the symbol of a pigment shows a color index number, for example, "PR 254" means "C. I. Pigment Red 254, PY 150 is C. I. Pigment Yellow 150 ”.

In addition, in the following example, various physical properties were measured by the following method.

<Measurement method of various physical properties>

[Mean Primary Particle Diameter of Pigment]

Using the transmission electron microscope ("JEM-1200EX" by JEOL Corporation), the primary particle diameter of all the pigment particles in the observation sample at 50,000 times was measured, and the average value was made into the average primary particle diameter. In addition, when particle shape was not spherical, the long diameter and short diameter were measured, and the value calculated | required by (long diameter + short diameter) / 2 was made into particle diameter.

[Color and Contrast]

The red colored composition was applied to the glass substrate by spin coating to make the chromaticity x after curing become 0.64 (F10 light source), dried at 70 ° C. for 20 minutes, and then exposed to ultraviolet rays using an ultrahigh pressure mercury lamp. Then, this board | substrate was heat-processed at 230 degreeC for 1 hour, and the red colored film was obtained. About this red colored film, the chromaticity (Y, x, y) in the F10 light source was measured using the microscope spectrophotometer ("OSP-SP100" by Olympus Optical). Moreover, the polarizing plate was piled up on both sides of the board | substrate which formed the red coloring film, and the polarizing plate computed ratio Lp / Lc of the brightness | luminance Lp at the time of parallel and the luminance Lc at the orthogonal angle as contrast. The luminance was measured under the condition of a 2 ° field of view using a color luminance meter ("BM-5A" manufactured by Topcon Corporation).

In addition, the pigment derivatives D-1 to D-3 used for the following manufacture examples are shown below.

<Production of Micronized Pigment>

Preparation Example 1

100 parts of diketopyrrolopyrrole red pigment PR 254 (“Irgapor red B-CF” manufactured by Chivas Specialty Chemicals), 10 parts of pigment derivative (D-1), crushed sodium chloride 1000 parts, and 120 parts of diethylene glycol It put into the stainless 1 gallon kneader (made by Inoue Co., Ltd.), and knead | mixed at 60 degreeC for 10 hours. The mixture was poured into 2000 parts of warm water, stirred at a high speed mixer for about 1 hour while heating to about 80 ° C. to form a slurry, and repeated filtration and washing to remove sodium chloride and solvent, followed by drying at 80 ° C. for 24 hours. And refined pigment (R-1) were obtained. The average particle diameter of the obtained pigment was 25 nm.

Preparation Example 2

100 parts of anthraquinone type red pigment PR177 ("chromophthal red A2B" made by Chivas Specialty Chemicals), 8 parts of dye derivatives (D-2), 700 parts of crushed sodium chloride, and 180 parts of diethylene glycol 1 gallon kneader made of stainless steel (Inoue Co., Ltd. product), and kneaded at 70 ℃ 4 hours. The mixture was poured into 4000 parts of hot water, stirred at a high speed mixer for about 1 hour while heating to about 80 ° C. to form a slurry, and filtration and washing were repeated to remove sodium chloride and solvent, followed by drying at 80 ° C. for 24 hours. To obtain fine pigment (R-2). The average particle diameter of the obtained pigment was 30 nm.

Preparation Example 3

100 parts of perylene-based red pigment PR 179 ("Pariogen maroon L-3920" by Bayer Corporation), 8 parts of pigment derivatives (D-2), 1000 parts of crushed sodium chloride, and 120 parts of diethylene glycol, 1 gallon kneader made of stainless It injected | threw-in to (Inoue Co., Ltd. product), and knead | mixed at 60 degreeC for 8 hours. The mixture was poured into 2000 parts of warm water, stirred at a high speed mixer for about 1 hour while heating to about 80 ° C. to form a slurry, and repeated filtration and washing to remove sodium chloride and solvent, followed by drying at 80 ° C. for 24 hours. And refined pigment (R-3) were obtained. The average particle diameter of the obtained pigment was 35 nm.

Preparation Example 4

100 parts of quinophthalone-based yellow pigment PY 138 ("Pariotol Elo K0961 HD" by BASF Corporation), 5 parts of pigment derivative (D-3), 750 parts of pulverized sodium chloride, and 180 parts of diethylene glycol (1 gallon kneader) To Inoue Co., Ltd.), and kneaded at 60 ° C for 6 hours. The mixture was poured into 3000 parts of warm water, stirred at a high speed mixer for about 1 hour while heating to about 80 ° C. to form a slurry, and repeated filtration and washing to remove sodium chloride and solvent, followed by drying at 80 ° C. for 24 hours. And refined pigment (Y-1) were obtained. The average particle diameter of the obtained pigment was 40 nm.

<Production of Acrylic Resin Solution>

370 parts of cyclohexanone were put into the reaction vessel, heated to 80 ° C while injecting nitrogen gas into the container, and 20.0 parts of methacrylic acid, 10.0 parts of methyl methacrylate, 55.0 parts of N-butyl methacrylate and 2- at the same temperature. A mixture of 15.0 parts of hydroxyethyl methacrylate and 4.0 parts of 2,2'-azobisisobutyronitrile was added dropwise over 1 hour to conduct a polymerization reaction. After completion | finish of dripping, after making it react for 3 hours at 80 degreeC, the thing which melt | dissolved 1.0 part of azobisisobutyronitrile in 50 parts of cyclohexanone was added, and reaction continued at 80 degreeC for 1 hour, and the solution of the acrylic resin Got. The weight average molecular weight of the acrylic resin was about 40000. After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and based on the measurement result, cyclohexanone was added to the synthesized resin solution so that the nonvolatile content was 20% by weight. Rice fields were added to prepare an acrylic resin solution.

<Production of Pigment Dispersion>

The mixture of the composition shown in Table 1 was stirred and mixed uniformly, it disperse | distributed for 3 hours with the Eiger mill ("Minimo M-250MKH" by the Iger Japan company) using zirconia beads of diameter 1mm, and it filtered with a 5 micrometer filter. To obtain various pigment dispersions. In Table 1, the content rate of the pigment in each pigment dispersion was also written together.

<Preparation of red coloring composition>

Example 1

21.2 parts of pigment dispersion (RP-1), 20,1 part of pigment dispersion (RP-2), 9.7 parts of pigment dispersion (YP-2), 1.0 part of acrylic resin solution, trimetholpropane triacrylate (new) 4.0 parts of "NK ester ATMPT" made by Nakamura Kagaku Co., Ltd., 3.4 parts of photoinitiator ("Irugacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizer ("EAB-F" by Hodogaya Kagaku Co., Ltd.) and cyclohexa After stirring and mixing 40.2 parts of paddy fields uniformly, it filtered by the filter of 1 micrometer and obtained 100 parts of red coloring compositions (RR-1). Table 2 shows the blending ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Example 2

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 part of acrylic resin solution, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-2). Table 3 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Example 3

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 part of acrylic resin solution, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-3). Table 2 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Comparative Example 1

20.2 parts of pigment dispersion (RP-2), 21.0 parts of pigment dispersion (RP-3), 9.8 parts of pigment dispersion (YP-2), 1.0 part of acrylic resin solution, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-4). Table 2 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of the chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Comparative Example 2

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 part of acrylic resin solution, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-5). Table 2 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Comparative Example 3

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, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-6). Table 2 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

Comparative Example 4

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 part of acrylic resin solution, trimetholpropane triacrylate (Shinakamuraka 4.0 parts of "NK ester ATMPT" made by Gaku Corporation, 3.4 parts of photoinitiators ("Irgacure 907" made by Chiba Specialty Chemicals, Inc.), 0.4 part of sensitizers ("EAB-F" by Hodogaya Chemical Co., Ltd.), and cyclohexanone 40.2 The mixture was stirred and mixed so as to be uniform, and then filtered through a 1 μm filter to obtain 100 parts of a red colored composition (RR-7). Table 2 shows the mixing ratios of the various pigments in the obtained red colored composition. Table 3 shows the results of chromaticity and contrast of the red colored film produced by applying the obtained red colored composition to a glass substrate.

As shown in Table 3, in the red colored film formed using the colored compositions of Examples 1 to 3 of the present invention, the chromaticity y when x is 0.64 is in the range of 0.30 to 0.35, and the brightness Y value is 23 or more. In addition, the contrast also achieves a high value.

On the other hand, in the red colored film formed using the coloring composition of the comparative example 1, the brightness Y value is greatly less than 23. This is considered to be because the absorption of the red bright line of the backlight was increased by using PR 179 in which the transmission spectrum near 600 nm approached the longer wavelength side than PR 254 instead of PR 254. Moreover, in the red colored film of Comparative Examples 2-4, contrast becomes a low value. In Comparative Examples 2 and 3, a red pigment having an average primary particle diameter exceeding the upper limit (50 nm) of the prescribed range of the present invention was used. In Comparative Example 4, PY138 was used as a yellow pigment. The action becomes remarkable, and the contrast is considered to be a low value.

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

In addition, by using the color filter of the present invention, high brightness and high contrast of the liquid crystal display device can be achieved.

Claims (7)

As a red coloring composition for color filters containing a transparent resin, a precursor thereof, or a mixture thereof, and a red colorant, the red colorant is diketopyrrolopyrrole red pigment, anthraquinone red pigment, and azo yellow. A red coloring composition for color filters, containing at least three pigments of pigments, wherein the average primary particle diameter of each pigment is 10 to 50 nm. 2. The chromaticity when x is 0.64 when the red colored film is formed using the red colored composition for color filters, and the chromaticity of the XYZ colorimeter is measured using the F10 light source. y is in the range of 0.30 to 0.35, and the brightness Y value is 23 or more. The diketopyrrolopyrrole-based red pigment comprises 30 to 75% by weight, the anthraquinone-based red pigment comprises 20 to 60% by weight based on the total weight of the three pigments. A red coloring composition for color filters, wherein the yellow pigment accounts for 5 to 30% by weight. The color of claim 1, wherein the diketopyrrolopyrrole red pigment is CI Pigment Red 254, the anthraquinone red pigment is CI Pigment Red 177, and the azo yellow pigment is CI Pigment Yellow 150. Red coloring composition for the filter. The red coloring composition for a color filter according to claim 1, wherein the coloring medium carrier is contained in a proportion of 30 to 700 parts by weight based on 100 parts by weight of the total red colorant. The color filter provided with the red filter segment formed using the red coloring composition for color filters in any one of Claims 1-5. A liquid crystal display device comprising the color filter according to claim 6.

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