CN109642970B

CN109642970B - Pigment composition for color filter and color filter

Info

Publication number: CN109642970B
Application number: CN201780051904.9A
Authority: CN
Inventors: 坂本圭亮; 木村亮; 岛田望; 千叶祐奈; 石井融
Original assignee: DIC Corp
Current assignee: DIC Corp
Priority date: 2016-08-31
Filing date: 2017-08-30
Publication date: 2021-09-10
Anticipated expiration: 2037-08-30
Also published as: KR102383525B1; WO2018043548A1; JPWO2018043548A1; KR20190045183A; CN109642970A; JP6477977B2

Abstract

Provided are a novel pigment composition for a color filter, which can produce a color filter with high luminance, and a color filter containing the pigment composition for a color filter. The pigment composition for color filter contains green pigment, and the green pigment has the following spectral characteristics: when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, the transmittance at a wavelength of 555nm is 45% or more, the ratio of the transmittance at a wavelength of 505nm to the transmittance at a wavelength of 555nm (T (505nm)/T (555nm)) is 1.40 or more, and the half-value width is 80nm or less. The color filter contains the pigment composition for the color filter.

Description

Pigment composition for color filter and color filter

Technical Field

The present invention relates to a pigment composition for a color filter and a color filter.

Background

A color filter used in a liquid crystal display is a member that realizes color display of the display by transmitting backlight white light. Among them, green colorants for color filters are required to have high brightness and high color reproduction.

In order to achieve high luminance, it is important to select a pigment having high transmittance against a backlight, and pigment green 58 is used as a main pigment. Since the luminance of the pigment is increased, the backlight white light can be effectively used, and thus energy saving and manufacturing cost reduction of the display can be achieved. Since the current display is designed as sRGB, the display is designed so that the luminance of a green pixel becomes (x, y) — (0.300, 0.600) is high. Currently, 3-color LEDs are less cost effective as LEDs for backlights. Therefore, pseudo-white LEDs (a combination of a blue LED and a yellow phosphor (B-YAG), and a combination of a blue LED and a red phosphor and a green phosphor (B-RG)) formed by coating a phosphor on the surface of a blue LED are becoming mainstream. When such a white LED backlight is used, the green emission intensity is weak as compared with the blue emission intensity, and thus the transmittance of the green colored layer is lowered. Therefore, high luminance of the green coloring layer is required.

Among these, in order to achieve high color reproduction, a pigment is selected which has high luminance and can display a clear color. The film thickness of the color filter can be increased in order to realize sharp color display, but the film thickness must be controlled to be about 3 μm or less in order to sufficiently cure the coating film in the exposure step. A high-color reproduction display expected to be widespread in the future is designed by DCI-P3. However, if pigment green 36, 58 is used, the film thickness will greatly exceed 3 μm, so pigment green 7 is selected as the main pigment. For example, it has been proposed to form a green pixel using a green photosensitive resin composition containing pigment green 7 and pigment yellow 185 and realize high color reproduction with a thin film of 2.2 μm or less. However, pigment green 7 has lower transmittance than pigment green 36 and 58. Therefore, there is a problem that the luminance of the obtained display is lowered.

The luminance can be compensated for by increasing the amount of backlight light, but a new problem arises in that the power consumption increases. Therefore, both luminance and color reproducibility are required. A new pigment with high color reproduction is pigment green 59, and compared with the case of manufacturing a color filter having the same film thickness, the luminance is higher when pigment green 59 is used than when pigment green 7 is used (see, for example, patent document 1).

From the above, it is preferable to use pigment green 58 for a color filter for a high-luminance display, and to use pigment green 59 for a color filter for a high-color reproduction display.

Among them, a large difference between the color filter for a high-luminance display and the color filter for a high-color reproduction display is in designing the chromaticity of the green pixel and the kind of the backlight.

In a conventional color filter for a high-luminance display, the chromaticity is sRGB (x, y) ═ 0.300, 0.600, and B-YAG is the mainstream of the backlight. However, since B-YAG differs depending on the manufacturing company, a color filter is evaluated using a C light source with (x, y) — (0.275, 0.570) (see, for example, patent document 2).

Among them, the color filters predicted to be used for the high color reproduction display have a chromaticity of DCI-P3 and a backlight of B-RG. However, since B-RG varies depending on the manufacturing company, a color filter is evaluated using a C light source with (x, y) — (0.250, 0.615) (see, for example, patent document 3).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-057635

Patent document 2: japanese laid-open patent publication No. 2014-085562

Patent document 3: japanese patent application laid-open No. 2011-117986

Disclosure of Invention

Problems to be solved by the invention

As described above, it is preferable to use pigment green 58 for a color filter for a high-luminance display. However, in order to compensate for the characteristics of B-YAG as a backlight having a weak green emission intensity, it is desired to further increase the luminance of the green pigment.

Accordingly, the present invention has been made in view of the above circumstances, and provides a novel pigment composition for a color filter capable of producing a color filter with high luminance, and a color filter containing the pigment composition for a color filter.

Means for solving the problems

As a result of intensive studies to solve the above problems, the present inventors have found that a color filter having higher luminance than conventional ones can be formed by using a pigment composition for a color filter having specific spectral characteristics, and have completed the present invention.

That is, the present invention includes the following aspects.

A pigment composition for color filters according to embodiment 1 of the present invention contains a green pigment having the following spectral characteristics: when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, the transmittance at a wavelength of 555nm is 45% or more, the ratio of the transmittance at a wavelength of 505nm to the transmittance at a wavelength of 555nm (T (505nm)/T (555nm)) is 1.40 or more, and the half-value width is 80nm or less.

The aforementioned green pigment may be zinc chloride bromide phthalocyanine.

The green pigment may be zinc bromide phthalocyanine chloride containing an average of 13 to 15 bromines and an average of 1 to 3 chlorines in 1 molecule.

The pigment composition for color filters according to embodiment 1 may further contain a yellow pigment.

The color filter according to embodiment 2 of the present invention contains the pigment composition for color filters according to embodiment 1.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the pigment composition for a color filter of the above-mentioned embodiment, a color filter having high luminance can be produced.

Drawings

FIG. 1A is a graph showing the spectral transmission spectra (wavelengths 480 to 580nm) of the compositions for evaluation 1 to 7 and 9 to 12 in example 1 and comparative example 1.

FIG. 1B is a graph showing the spectral transmission spectra (wavelengths 440 to 480nm) of the compositions 1 to 7 and 9 to 12 for evaluation in example 1 and comparative example 1.

FIG. 1C is a graph showing the spectral transmission spectra (wavelengths 580 to 620nm) of the compositions for evaluation 1 to 7, 9, 10 and 12 in example 1 and comparative example 1.

Detailed Description

Pigment composition for color filter

In one embodiment, the present invention provides a pigment composition for a color filter, which contains a green pigment having the following spectral characteristics (a) to (c) when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%.

(a) The transmittance at a wavelength of 555nm is more than 45%,

(b) the ratio of the transmittance at a wavelength of 505nm to the transmittance at a wavelength of 555nm (T (505nm)/T (555nm)) is 1.40 or more,

(c) the half-value width is 80nm or less.

According to the pigment composition for a color filter of the present embodiment, a high-luminance color filter capable of compensating the characteristics of LED-YAG which is a backlight having a small amount of green light can be provided.

The spectral transmittance in the present specification can be obtained by measuring a spectral transmittance spectrum.

The "light-splitting transmission spectrum" is determined based on the first kind of spectrophotometer of japanese industrial standard JIS Z8722 (method of measuring color-reflection and transmission of object color (method of sensing the color of the periphery) (reflection and weaving of the color of the object). Specifically, the resin coating film containing a pigment, which is formed on a glass substrate or the like in the predetermined dry film thickness, is scanned with light irradiated in a predetermined wavelength range, and the transmittance values at the respective wavelengths are plotted.

< constituent Material >

[ Green pigment ]

The green pigment contained in the pigment composition for a color filter of the present embodiment has the following spectral characteristics (a) to (c) when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%.

(a) The transmittance at a wavelength of 555nm is more than 45%,

(c) the half-value width is 80nm or less.

In the green color filter, it is important to improve the transmittance in the range of 510nm to 560nm in order to ensure the brightness. When the color is adjusted with a yellow pigment, the yellow pigment is mixed, and the wavelength is shifted to the long wavelength side by about 5 nm. Therefore, in order to obtain a bright display, it is important to increase the transmission wavelength at 505nm while maintaining a high transmittance at 555 nm.

On the other hand, when the 460nm transmittance is high, the chromaticity y value is greatly reduced, and the green vividness (chroma) is lost, so that the 460nm transmittance is preferably low after toning with a yellow pigment. For example, the yellow pigment Y138 is a pigment which absorbs on the shorter wavelength side than 460nm, and if the transmittance at 460nm of the green pigment is high, it must be designed to extremely increase the amount of Y138 used. Therefore, in order to display (x, y) — (0.275, 0.570), the color filter needs to be made thick. The thickening of the color filter is not preferable because it causes a decrease in luminance. That is, the transmittance of the green pigment at 460nm is preferably low. When a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, it is preferable that the 460nm transmittance of the green pigment is 3% or less from the viewpoint of increasing the chromaticity y value. More preferably 2% or less, and still more preferably 1% or less.

Among them, when the transmittance at 605nm is high, the chroma x is increased and the vividness (chroma) of green is lost, so that it is preferable that the transmittance at 605nm is low after toning with a yellow pigment. Since the shift to the long wavelength side is about 5nm by toning with a yellow pigment, the green pigment preferably has a low transmittance of 600 nm. When a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, a transmittance of 600nm of the green pigment of 1% or less is preferable from the viewpoint of reducing the chromaticity x value. More preferably 0.5% or less, and still more preferably 0.3% or less.

That is, in order to achieve high luminance and excellent color reproducibility, a green pigment having a large transmission spectrum of T (505nm)/T (555nm) and low transmittances at 460nm and 600nm is required.

The green pigment contained in the pigment composition for color filters of the present embodiment has the spectral characteristics (a) to (c) described above when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, and thus, as shown in examples described below, a color filter having higher luminance than conventional green pigments can be obtained. In addition, when the green pigment contained in the pigment composition for a color filter of the present embodiment forms a coating film so that the spectral transmittance at the maximum transmission wavelength is 80%, the transmittances at 460nm and 600nm are reduced. Therefore, as shown in examples described later, a color filter having color reproducibility superior to that of a conventional green pigment can be obtained.

When the green pigment contained in the pigment composition for color filters of the present embodiment forms a coating film so that the spectral transmittance at the maximum transmittance wavelength is 80%, the maximum transmittance wavelength in the coating film is preferably in the range of 515nm to 530 nm.

The green pigment having the spectral characteristics may be an inorganic pigment or an organic pigment. Among them, the green pigment is preferably an organic pigment, more preferably a phthalocyanine compound, and still more preferably a phthalocyanine compound having a metal atom at the center.

In the present specification, the "phthalocyanine compound" is a cyclic compound having a structure in which 4 phthalimides are crosslinked by a nitrogen atom. The "phthalocyanine compound having a metal atom at the center" is a compound having a structure in which 4 nitrogen atoms at the center of the phthalocyanine compound are chemically bonded (for example, covalently bonded, coordinately bonded, or the like) to the metal atom.

The metal atom present in the center of the phthalocyanine compound is not particularly limited, and examples thereof include Zn, Mg, Al, Si, Ti, V, Mn, Fe, Co, Ni, Ge, and Sn. Among them, Zn (zinc) is preferable as the metal atom existing at the center of the phthalocyanine compound.

The phthalocyanine compound having a metal atom as the center in the green pigment is preferably zinc phthalocyanine, more preferably halogenated zinc phthalocyanine, and still more preferably brominated zinc phthalocyanine chloride.

When the green pigment is zinc chloride bromide phthalocyanine, it is preferable that 1 molecule contains 14 to 16 halogen atoms on average, 13 to 15 bromine atoms on average, and 1 to 3 chlorine atoms on average, from the viewpoint of having the above spectral characteristics.

Among them, if the halogenation rate is increased, the hue of the pigment is yellowed, and therefore, by increasing the number of bromine atoms in 1 molecule of brominated zinc chloride phthalocyanine to the number of chlorine atoms, a green pigment having high brightness can be produced while maintaining the hue of green. Among these, in the green pigment of the present embodiment, the number of bromine in 1 molecule of brominated zinc chloride phthalocyanine is preferably 7 times or more, more preferably 7 times or more and 9 times or less, and further preferably 7.8 times or more and 9 times or less, as large as the number of chlorine on average.

The number of halogen atoms in 1 molecule of the brominated zinc chloride phthalocyanine can be measured by a method (fluorescent X-ray analysis) described in examples below.

(method for producing Green pigment)

The halogenated metal phthalocyanine in the green pigment can be produced by various known production methods such as a chlorosulfonic acid method, a halogenated phthalonitrile method, and a melting method.

Examples of the chlorosulfonic acid method include a method in which metal phthalocyanine is dissolved in a sulfur oxide-based solvent such as chlorosulfonic acid, and chlorine gas or bromine is added thereto to perform halogenation. The reaction at this time is carried out at a temperature of 20 ℃ to 120 ℃ and within a range of 3 hours to 20 hours.

Examples of the halogenated phthalonitrile method include a method of synthesizing a corresponding halogenated metal phthalocyanine by using phthalic acid or phthalonitrile in which a part or all of hydrogen atoms of an aromatic ring are substituted with a halogen atom such as bromine or chlorine, and zinc metal or a zinc metal salt as a starting material. In this case, a catalyst such as ammonium molybdate may be used as necessary. The reaction at this time is carried out at a temperature of 100 ℃ to 300 ℃ and within a range of 7 hours to 35 hours.

Examples of the melting method include a method of halogenating a metal phthalocyanine with a halogenating agent in a melt at about 10 ℃ to 170 ℃ of a mixture containing one or two or more compounds as solvents in various halogenation processes, such as aluminum halide such as aluminum chloride and aluminum bromide, titanium halide such as titanium tetrachloride, alkali metal halide such as sodium chloride and sodium bromide, alkaline earth metal halide (hereinafter, sometimes referred to as "alkali (earth) metal halide"), and thionyl chloride.

The aluminum halide is preferably aluminum chloride. In the above melting method using an aluminum halide, the amount of the aluminum halide added is usually 3 times by mol or more, preferably 10 times by mol or more and 20 times by mol or less, relative to the zinc phthalocyanine.

The aluminum halide may be used alone, and if an alkali (earth) metal halide is used in combination with the aluminum halide, the melting temperature can be further lowered, which is advantageous in terms of handling. The alkali (earth) metal halide is preferably sodium chloride. The amount of the alkali (earth) metal halide to be added is preferably 5 parts by mass or more and 15 parts by mass or less with respect to 10 parts by mass of the aluminum halide in the range where the molten salt is produced.

Examples of the halogenating agent include chlorine gas, sulfuryl chloride, and bromine.

The halogenation temperature is preferably from 10 ℃ to 170 ℃ and more preferably from 30 ℃ to 140 ℃. Further, in order to accelerate the reaction rate, pressure may be applied. The reaction time is preferably 5 hours to 100 hours, more preferably 30 hours to 45 hours.

As a method for producing a halogenated metal phthalocyanine, a melting method in which two or more compounds are used in combination as a solvent in the halogenation is preferable. For this reason, in this method, the content ratio of the zinc halide phthalocyanine having a specific halogen atom composition in the produced zinc halide phthalocyanine can be arbitrarily controlled by adjusting the ratio of chloride, bromide and iodide in the molten salt, or by changing the amount of chlorine, bromine and iodine introduced or by changing the reaction time.

The metal phthalocyanine which becomes a suitable raw material in the present embodiment is zinc phthalocyanine. The melting method is preferable in obtaining zinc halide phthalocyanine because decomposition of the raw material is less in the reaction, the yield obtained from the raw material is more excellent, and the reaction is carried out in an inexpensive apparatus without using a strong acid.

By optimizing the raw material charging method, the type of catalyst, the amount of catalyst used, the reaction temperature and the reaction time, the zinc halide phthalocyanine having a halogen atom composition different from that of the existing zinc halide phthalocyanine can be obtained.

In any of the above-mentioned production methods, when the resulting mixture is introduced into an acidic aqueous solution such as water or hydrochloric acid after the reaction is completed, the produced halogenated metal phthalocyanine is precipitated. The halogenated metal phthalocyanine may be used as it is, but it is preferably used after filtration, or after washing with water, sodium hydrogen sulfate, sodium hydrogen carbonate, or sodium hydroxide, washing with an organic solvent such as acetone, toluene, methanol, ethanol, or dimethylformamide as necessary, and drying or other post-treatment.

The halogenated metal phthalocyanine is subjected to dry milling in a pulverizer such as a super-fine mill, a ball mill, a vibration mill, or a vibration ball mill, if necessary, and then is subjected to pigmenting by a solvent salt milling method, a solvent boiling method, or the like, thereby obtaining a pigment which is superior in dispersibility and tinting strength and emits a green color with high brightness compared to that before pigmenting.

The method for pigmenting the halogenated metal phthalocyanine is not particularly limited, and for example, the halogenated metal phthalocyanine before pigmenting may be dispersed in a dispersion medium and simultaneously pigmenting the dispersion medium. Among them, as a method for pigmenting a halogenated metal phthalocyanine, a solvent salt milling treatment is preferably employed in that the crystal growth can be easily suppressed and pigment particles having a large specific surface area can be obtained, as compared with a solvent treatment in which a halogenated metal phthalocyanine is heated and stirred in a large amount of an organic solvent.

The solvent salt milling means that a crude pigment which is a non-pigmented halogenated metal phthalocyanine milled immediately after or after the synthesis is kneaded and milled with an inorganic salt and an organic solvent. In this case, the latter crude pigment is more preferably used. Specifically, a crude pigment, an inorganic salt, and an organic solvent which does not dissolve them are added to a mixer, and mixing and grinding are performed therein. As the kneading machine in this case, for example, a kneader, a mixing mill (ミックスマーラー), or the like can be used.

As the inorganic salt, a water-soluble inorganic salt can be suitably used, and for example, inorganic salts such as sodium chloride, potassium chloride, and sodium sulfate are preferably used. Further, it is more preferable to use an inorganic salt having an average particle diameter of 0.5 μm or more and 50 μm or less. Such an inorganic salt can be easily obtained by finely pulverizing a general inorganic salt.

In the present embodiment, the halogenated metal phthalocyanine pigment having an average primary particle size of 50nm or less is preferably used for color filter applications. In order to obtain the preferable halogenated metal phthalocyanine in the present embodiment, it is preferable to increase the amount of the inorganic salt used relative to the amount of the crude pigment used in the solvent salt milling. That is, the amount of the inorganic salt used is preferably 5 parts by mass or more and 20 parts by mass or less, more preferably 7 parts by mass or more and 15 parts by mass or less, relative to 1 part by mass of the crude pigment.

As the organic solvent, an organic solvent capable of suppressing crystal growth is preferably used. As such an organic solvent, a water-soluble organic solvent can be suitably used. Specific examples of the water-soluble organic solvent include diethylene glycol, glycerin, ethylene glycol, propylene glycol, liquid polyethylene glycol, liquid polypropylene glycol, 2- (methoxymethoxy) ethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, and dipropylene glycol monomethyl ether. The amount of the water-soluble organic solvent used is not particularly limited, but is preferably 0.01 to 5 parts by mass based on 1 part by mass of the crude pigment.

The temperature at the time of polishing the solvent salt is preferably 30 ℃ to 150 ℃, more preferably 80 ℃ to 100 ℃. The time for polishing the solvent salt is preferably 5 hours to 20 hours, more preferably 8 hours to 18 hours.

Thus, a mixture containing, as main components, a halogenated metal phthalocyanine pigment having an average primary particle diameter of 50nm or less, an inorganic salt and an organic solvent can be obtained. The organic solvent and the inorganic salt are removed from the mixture, and the solid substance mainly composed of the halogenated metal phthalocyanine pigment is washed, filtered, dried, pulverized, and the like as necessary, thereby obtaining a powder of the halogenated metal phthalocyanine pigment.

As the washing, either water washing or hot water washing may be employed. The number of washing may be repeated within a range of 1 to 5 times. When the mixture of the water-soluble inorganic salt and the water-soluble organic solvent is used, the organic solvent and the inorganic salt can be easily removed by washing with water. If necessary, acid cleaning, alkali cleaning, and organic solvent cleaning may be performed without changing the crystal state.

Examples of the drying after the filtering and washing include batch-type or continuous drying in which at least one of the pigment is dehydrated or desolventized by heating at 80 ℃ to 120 ℃ by a heating source provided in a dryer. The dryer generally includes a box dryer, a belt dryer, a spray dryer, and the like. In particular, spray drying is preferable because it is easily dispersed when made into a paste. The pulverization after drying is not intended to increase the specific surface area or to decrease the average particle size of the primary particles. The pulverization after drying is performed, for example, to disintegrate and pulverize the pigment when the pigment is in a slope form (ランプ form) as in the case of drying using a box dryer or a belt dryer. Examples of the pulverizer used after drying include a mortar, a hammer mill, a disc mill, a pin mill, and a jet mill. Thus, a dried powder of a pigment containing a halogenated metal phthalocyanine pigment as a main component was obtained.

The green pigment may contain 1 kind of compound as a coloring source, or may contain 2 or more kinds. When 2 or more compounds are contained, the compounds contained in the green pigment may be mixed and then pigmented, or the compounds contained in the green pigment may be pigmented and then mixed.

[ yellow pigment ]

In addition, the pigment composition for a color filter of the present embodiment may contain at least 1 or more kinds of yellow pigments together with the above-described green pigment in order to form a green pixel.

Examples of the yellow pigment include c.i. Pigment Yellow (PY)1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35:1, 36:1, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 126, 127, 128, 129, 138, 139, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 199, 231, and the like. Among these, PY83, 138, 139, 150, 185, or 231 is preferable, and PY138, 150, 185, or 231 is particularly preferable, since the brightness is high or the pigment is small in amount and is suitable for thin film formation. 1 or 2 or more of them may be used in combination.

When the yellow pigment is mixed to prepare the pigment composition for color filters, the mixing ratio of the green pigment to the yellow pigment may be 1 to 400 parts by mass of the yellow pigment per 100 parts by mass of the green pigment.

In addition, in the pigment composition for a color filter of the present embodiment, even when a yellow pigment is used in combination for color mixing, a color filter green pixel portion having higher luminance than that in the case of using a conventional green pigment can be produced.

< method for producing pigment composition for color Filter >

The pigment composition for color filters of the present embodiment can be produced by a known production method.

The method for producing the green pigment is as described above.

Specifically, the green pigment and, if necessary, the yellow pigment may be dry-milled in a pulverizer such as a super-fine mill, a ball mill, a vibration mill, or a vibration ball mill, and then subjected to pigmenting by a solvent salt milling method, a solvent boiling method, or the like.

The details of the pigmentation method are as described above (method for producing green pigment).

In the pigment composition for color filters of the present embodiment, the average particle size of the primary particles is 50nm or less, preferably 1nm to 50nm, the pigment aggregation is relatively weak, and the dispersibility in synthetic resins or the like to be colored is better. Further, it is more preferably 1nm to 20 nm.

In the present embodiment, the "average primary particle size" can be calculated by the following measurement method. First, the particles of the pigment composition for a color filter of the present embodiment were photographed in a field of view with a transmission electron microscope JEM-2010 (manufactured by japan electronics corporation). Next, the longer diameter (major axis) of each of the primary particles of the pigment composition for color filters of the present embodiment, in which 50 aggregates are formed on the two-dimensional image, was determined. Next, the average particle diameter of the primary particles can be calculated by averaging the obtained major diameters. At this time, the pigment composition for a color filter of the present embodiment as a sample was subjected to ultrasonic dispersion in a solvent and photographed with a microscope. Among them, a scanning electron microscope may be used instead of the transmission electron microscope.

< use >

A color filter can be obtained by forming a green pixel using the pigment composition for a color filter of the present embodiment.

The green pixel formed using the pigment composition for a color filter of the present embodiment has high luminance. Therefore, a liquid crystal display device including a color filter having the green pixel and having high display performance and a liquid crystal panel can be manufactured.

(method for manufacturing color Filter)

The pigment composition for a color filter of the present embodiment can be used for forming a pattern of a green pixel portion of a color filter by a known method. Typically, a photosensitive composition for a green pixel portion of a color filter containing the pigment composition for a color filter of the present embodiment and a photosensitive resin as essential components can be obtained.

Examples of the method for manufacturing a color filter include a method referred to as photolithography described below. Specifically, first, the pigment composition for a color filter of the present embodiment is dispersed in a dispersion medium containing a photosensitive resin. Next, the dispersion is applied onto a transparent substrate such as glass by a spin coating method, a roll coating method, a slit coating method, an ink jet method, or the like to obtain a coating film. Then, the coating film is subjected to pattern exposure through a photomask by ultraviolet rays. Next, the unexposed portion is washed with a solvent or the like to obtain a green pattern.

As another manufacturing method, for example, a method of forming a pattern of a green pixel portion by a method such as an Electrodeposition method, a transfer method, a micelle electrolysis method, or a PVED (Photovoltaic electro deposition) method to manufacture a color filter is cited. The pattern of the red pixel portion and the pattern of the blue pixel portion may be formed by the same method using a known pigment.

In the preparation of the photosensitive composition for a green pixel portion of a color filter, for example, the pigment composition for a color filter of the present embodiment, a photosensitive resin, a photopolymerization initiator, and an organic solvent for dissolving the resin are mixed as essential components. More specifically, a method is generally used in which a dispersion liquid is prepared by using the pigment composition for a color filter of the present embodiment, an organic solvent, and if necessary, a dispersant, and then a photosensitive resin or the like is added thereto to prepare the pigment composition.

Examples of the dispersant include DISPERBYK (ディスパービック, registered trademark) 130, DISPERBYK 161, DISPERBYK 162, DISPERBYK163, DISPERBYK 170, DISPERBYK LPN-6919, DISPERBYK LPN-21116, and the like, available from Bikk chemical company. Further, a leveling agent, a coupling agent, a cationic surfactant, and the like may be used in combination.

Examples of the organic solvent include aromatic solvents such as toluene, xylene and methoxybenzene, acetate solvents such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate, propionate solvents such as ethoxyethyl propionate, alcohol solvents such as methanol and ethanol, butyl cellosolve, ether solvents such as propylene glycol monomethyl ether, diethylene glycol ethyl ether and diethylene glycol dimethyl ether, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, aliphatic hydrocarbon solvents such as hexane, nitrogen compound solvents such as N, N-dimethylformamide, gamma-butyrolactam, N-methyl-2-pyrrolidone, aniline and pyridine, lactone solvents such as gamma-butyrolactone, and carbamates such as a mixture of methyl carbamate and ethyl carbamate 48:52, and mixtures of methyl carbamate and ethyl carbamate 48:52, Water, and the like. As the organic solvent, those which can be dissolved in water in polar solvents such as propionate, alcohol, ether, ketone, nitride, lactone, and water are particularly suitable. A high boiling point solvent having a boiling point of 150 ℃ or higher can be suitably used.

The dispersion liquid can be obtained by stirring and dispersing 300 parts by mass or more and 1000 parts by mass or less of the organic solvent and, if necessary, 0 part by mass or more and 100 parts by mass or less of the dispersant in such a manner as to be uniform, in accordance with 100 parts by mass of the pigment composition for color filters of the present embodiment. Next, in this dispersion, 3 to 20 parts by mass of a photosensitive resin and 0.05 to 3 parts by mass of a photopolymerization initiator are added to 100 parts by mass of the pigment composition for color filters of the present embodiment, and an organic solvent is further added as necessary to stir and disperse the mixture so as to be uniform, thereby obtaining a photosensitive composition for green pixel portions of color filters.

Examples of the photosensitive resin include thermoplastic resins such as urethane resin, acrylic resin, polyamic acid resin, polyimide resin, styrene maleic acid resin, and styrene maleic anhydride resin, 2-functional monomers such as 1, 6-hexanediol diacrylate, ethylene glycol diacrylate, neopentyl glycol diacrylate, triethylene glycol diacrylate, bis (acryloyloxyethoxy) bisphenol a and 3-methylpentanediol diacrylate, and photopolymerizable monomers such as trimethylolpropane triacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanate, dipentaerythritol hexaacrylate, and dipentaerythritol pentaacrylate.

Examples of the photopolymerization initiator include acetophenone, benzophenone, benzyl dimethyl ketal, benzoyl peroxide, 2-chlorothioxanthone, 1, 3-bis (4 '-azidobenzylidene) -2-propane-2' -sulfonic acid, and 4,4 '-diazidostilbene-2, 2' -disulfonic acid.

The prepared photosensitive composition for a green pixel portion of a color filter can be subjected to pattern exposure with ultraviolet rays through a photomask, and then the unexposed portion is washed with an organic solvent, alkaline water, or the like, thereby obtaining a color filter.

Examples

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[ production example 1] (pigment 1)

A300 mL flask was charged with 45 parts of sulfuryl chloride, 109 parts of aluminum chloride, 15 parts of sodium chloride, 30 parts of zinc phthalocyanine, and 300 parts of bromine. The temperature was raised to 145 ℃ over 40 hours, taken out into water and filtered to obtain crude pigment 1. 20 parts of the obtained crude pigment 1, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were charged into a 1L double arm kneader, and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of 30 ℃ water, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain pigment 1.

The obtained pigment 1 was subjected to fluorescent X-ray analysis using ZSX100E manufactured by physics corporation for the average number of chlorine atoms and the average number of bromine atoms, and calculated as a relative value for each zinc atom from the mass ratio of the zinc atom, the chlorine atom and the bromine atom. Wherein 1g of halogenated zinc phthalocyanine is subjected to press molding

The obtained sample was used as a measurement sample to

The diameter of the steel sheet was measured in a vacuum atmosphere. As a result, pigment 1 was the following halogenated zinc phthalocyanine pigment: the number of halogen atoms in 1 molecule was 15.73 on average, the number of bromine atoms was 14.13 on average, and the number of chlorine atoms was 1.60 on average. Further, the average particle diameter of the primary particles of the pigment 1 obtained by particle diameter measurement using a transmission electron microscope JEM-2010 manufactured by Nippon electronics, Inc. was 0.02. mu.m.

2.48 parts of the pigment 1 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 1. 4.0 parts of coloring composition 1, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 1 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 1 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 2] (pigment 2-2: pigment 1+ pigment 2-1)

A300 mL flask was charged with 91 parts of sulfuryl chloride, 109 parts of aluminum chloride, 15 parts of sodium chloride, 30 parts of zinc phthalocyanine, and 41 parts of bromine. The temperature was raised to 130 ℃ over 40 hours, taken out into water and filtered to obtain crude pigment 2. 20 parts of the obtained crude pigment 2, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were put into a 1L double arm kneader and kneaded at 100 ℃ for 6 hours. After kneading, the mixture was taken out to 2kg of 80 ℃ water, stirred for 1 hour, filtered, washed with hot water, dried and pulverized to obtain pigment 2-1. The obtained pigment 2-1 was analyzed by fluorescent X-ray analysis in the same manner as in production example 1. As a result, the pigment 2-1 was the following halogenated zinc phthalocyanine pigment: the number of halogen atoms in 1 molecule was 11.15 on average, the number of bromine atoms was 8.63 on average, and the number of chlorine atoms was 2.52 on average.

Next, 0.12 part of the obtained pigment 2-1 and 1.86 parts of the pigment 1 were thoroughly mixed to obtain a pigment 2-2. The obtained pigment 2-2 was analyzed by fluorescent X-ray analysis in the same manner as in production example 1. As a result, the pigment 2-2 was the following halogenated zinc phthalocyanine pigment: the number of halogen atoms in 1 molecule was 15.30 on average, the number of bromine atoms was 13.59 on average, and the number of chlorine atoms was 1.71 on average. Further, the average particle diameter of the primary particles of the pigment 2-2 obtained by particle diameter measurement using a transmission electron microscope JEM-2010 manufactured by Nippon electronics, Inc. was 0.02. mu.m.

2.48 parts of the pigment 2-2 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a coloring composition 2. 4.0 parts of coloring composition 2, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 2 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 2 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 3] (pigment 3)

A300 mL flask was charged with 60 parts of sulfuryl chloride, 109 parts of aluminum chloride, 15 parts of sodium chloride, 30 parts of zinc phthalocyanine, and 230 parts of bromine. The temperature was raised to 145 ℃ over 40 hours, taken out into water and filtered to obtain crude pigment 3. 20 parts of the obtained crude pigment 3, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were charged into a 1L double arm kneader, and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of water at 30 ℃ and stirred for 1 hour, followed by filtration, hot water washing, drying and pulverization to obtain pigment 3. The obtained pigment 3 was analyzed by fluorescent X-ray analysis in the same manner as in production example 1. As a result, pigment 3 was the following halogenated zinc phthalocyanine pigment: the number of halogen atoms in 1 molecule was 15.10 on average, the number of bromine atoms was 13.36 on average, and the number of chlorine atoms was 1.74 on average. Further, the average particle diameter of the primary particles of the pigment 3 obtained by particle diameter measurement using a transmission electron microscope JEM-2010 manufactured by Nippon electronics, Inc. was 0.02. mu.m.

2.48 parts of the pigment 3 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 3. 4.0 parts of coloring composition 3, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 3 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 3 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The monochromatic spectral transmission spectrum of the glass substrate for evaluation was measured using U-3900, manufactured by Hitachi high-tech. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 4] (pigment 4)

20 parts of crude pigment 1 of production example 1, 1.5 parts of TS-1316 manufactured by Star photo PMC, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were charged into a 1L double arm kneader and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of water at 30 ℃ and stirred for 1 hour, followed by filtration, hot water washing, drying and pulverization to obtain pigment 4. The average particle diameter of the primary particles of the pigment 4 obtained was 0.02 μm in terms of particle diameter measurement by a transmission electron microscope JEM-2010 manufactured by Japan electric Korea.

2.48 parts of the pigment 4 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 4. 4.0 parts of coloring composition 4, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 4 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 4 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 5] (pigment 5)

20 parts of crude pigment 1 of production example 1, 1.5 parts of VS-1028, a product of Star light PMC corporation, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were charged into a 1L double arm kneader and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of 30 ℃ water, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain pigment 5. The average particle diameter of the primary particles of the pigment 5 obtained was 0.02 μm according to the particle diameter measurement by a transmission electron microscope JEM-2010 manufactured by Japan electric Korea.

2.48 parts of the pigment 5 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 5. 4.0 parts of coloring composition 5, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 5 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 5 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 6] (pigment 6)

20 parts of crude pigment 1 of production example 1, 1.5 parts of X-1 manufactured by Star light PMC corporation, 140 parts of ground sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were charged into a 1L double arm kneader and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of 30 ℃ water, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain pigment 6. The average particle diameter of the primary particles of the pigment 6 obtained was 0.02 μm according to the particle diameter measurement by a transmission electron microscope JEM-2010 manufactured by Japan electric Korea.

2.48 parts of the pigment 6 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 6. 4.0 parts of coloring composition 6, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 6 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 6 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 7] (pigment 7)

20 parts of crude pigment 1 of production example 1, 1.5 parts of JONCRYL 690 manufactured by BASF corporation, 140 parts of pulverized sodium chloride, 32 parts of diethylene glycol and 1.8 parts of xylene were put into a 1L double arm kneader and kneaded at 30 ℃ for 15 hours. After kneading, the mixture was taken out into 2kg of 30 ℃ water, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain pigment 7. The average particle diameter of the primary particles of the pigment 7 obtained was 0.02 μm in terms of particle diameter measurement by a transmission electron microscope JEM-2010 manufactured by Japan electric Korea.

2.48 parts of the pigment 7 thus obtained was dispersed in a paint shaker for 2 hours together with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads to obtain a colored composition 7. 4.0 parts of coloring composition 7, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 7 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 7 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

[ production example 8] (dispersion of yellow pigment)

A coloring composition A was obtained by dispersing 1.65 parts of pigment Yellow 138 (Paliotol Yellow L0960HD, BASF corporation), 3.85 parts of DISPERBYK-161 (Bicke chemical corporation), and 11.00 parts of propylene glycol monomethyl ether acetate together with 0.3 to 0.4mm of zirconium beads in a paint shaker for 2 hours. 4.0 parts of coloring composition A, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain a composition for toning.

EXAMPLE 1 (toning with yellow pigment)

The color-adjusting composition was mixed with composition 1 for evaluation, composition 2 for evaluation, composition 3 for evaluation, composition 4 for evaluation, composition 5 for evaluation, composition 6 for evaluation, or composition 7 for evaluation so that the coating film color was (x, y) — (0.275, 0.570), and a film was formed, thereby obtaining a glass substrate for evaluation. The luminance under the C light source was measured using this glass substrate by U-3900, manufactured by Hitachi high and New technology. The results are shown in table 1 below.

Production example 9 pigment Green 58(FASTOGEN Green A110)

2.48 parts of pigment Green 58(FASTOGEN Green A110), 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate were dispersed together using 0.3 to 0.4mm zirconium beads with a paint shaker for 2 hours to obtain a coloring composition 9. 4.0 parts of coloring composition 9, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 9 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 9 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

Production example 10 pigment Green 59(FASTOGEN Green C100)

2.48 parts of pigment Green 59(FASTOGEN Green C100) was dispersed with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads with a paint shaker for 2 hours to obtain coloring composition 10. 4.0 parts of coloring composition 10, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 10 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 10 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

Production example 11 pigment Green 7(FASTOGEN Green S)

1.65 parts of pigment Green 7(FASTOGEN Green S), 1.93 parts of BYK-LPN 6919, and 12.93 parts of propylene glycol monomethyl ether acetate were dispersed with a paint shaker for 2 hours using 0.3 to 0.4mm zirconium beads to obtain a colored composition 11. 6.0 parts of coloring composition 11, 1.47 parts of UNIDIC ZL-295, and 0.33 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 11 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 11 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A and 1B. Among them, since pigment green 7 is a pigment having a low transmittance, it floats when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%, and thus no data is given in the spectral transmission spectrum in the range of 580 to 620nm shown in fig. 1C.

Production example 12 pigment Green 36(FASTOGEN Green 2YK-50)

2.48 parts of pigment Green 36(FASTOGEN Green 2YK-50) was dispersed with 1.24 parts of BYK-LPN 6919, 1.86 parts of UNIDIC ZL-295, and 10.92 parts of propylene glycol monomethyl ether acetate using 0.3 to 0.4mm zirconium beads with a paint shaker for 2 hours to obtain coloring composition 12. 4.0 parts of coloring composition 12, 0.98 parts of UNIDIC ZL-295, and 0.22 parts of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain composition 12 for evaluation for forming a green pixel portion for a color filter. This evaluation composition 12 was spin-coated on soda-lime glass and dried at 90 ℃ for 3 minutes to obtain an evaluation glass substrate. The glass substrate for evaluation was measured for monochromatic spectral transmission spectrum using U-3900, manufactured by Hitachi high-tech technology. The spectral transmission spectra are shown in fig. 1A, 1B, and 1C.

Comparative example 1 (toning with yellow pigment)

The toning composition was mixed with the evaluation composition 9, the evaluation composition 10, the evaluation composition 11, or the evaluation composition 12 so that the coating film color was (x, y) — (0.275, 0.570), and a film was formed, thereby obtaining a glass substrate for evaluation. The luminance under the C light source was measured using this glass substrate by U-3900, manufactured by Hitachi high and New technology. The results are shown in table 1 below.

[ Table 1]

From table 1 and fig. 1A, 1B and 1C, the compositions 1 to 7 for evaluation had a transmittance of 555nm of 50.47%, 50.28%, 47.41%, 45.73%, 46.45%, 50.07% and 45.89%, respectively, of 45% or more. The ratio of the transmittance at a wavelength of 505nm to the transmittance at a wavelength of 555nm ((A)/(B)) is 1.40, 1.44, 1.53, 1.57, 1.56, 1.42 and 1.59, and is 1.4 or more. Further, the half-value widths are 73nm, 75nm, 73nm, 68nm, 71nm and 68nm, and are 80nm or less.

By having the above spectral characteristics, the compositions 1 to 7 for evaluation had higher luminance after mixing with the toning composition so that (x, y) under a C light source was (0.275, 0.570) than the compositions 9 to 12 for evaluation containing the conventional green pigment.

The information obtained by summarizing the halogen ratios in the zinc halide phthalocyanine 1 molecules of the pigments 1 to 3 is shown in table 2.

[ Table 2]

According to Table 2, the average number of bromine atoms in 1 molecule of zinc halide phthalocyanine in pigments 1 to 3 was 14.13, 13.59 and 13.36, and was in the range of 13 to 15. In addition, 1 molecule of zinc halide phthalocyanine has 1.60, 1.71 and 1.74 chlorine atoms on average, and the number of chlorine atoms is in the range of 1 to 3. Further, the ratio ((E)/(F)) of the average number of bromine atoms to the average number of chlorine atoms in 1 molecule of the halogenated zinc phthalocyanine is 8.83, 7.94 and 7.69, and is 7 or more.

By adopting the above-mentioned halogen ratio, the pigments 1 to 3 can be green pigments having a higher brightness than the conventional green pigments such as the pigments green 58 and 59 while maintaining the hue of green.

From the above results, it is understood that a color filter having higher luminance than the conventional one can be formed by using a green pigment having specific spectral characteristics.

Industrial applicability

According to the pigment composition for a color filter of the present embodiment, a high-luminance color filter can be provided which can compensate for the characteristics of B-YAG which is a backlight having a weak green emission intensity. Further, since the green pixel luminance formed by using the pigment composition for a color filter of the present embodiment is high, a liquid crystal display device including a color filter having high display performance of the green pixel and a liquid crystal panel can be manufactured.

Claims

1. A pigment composition for color filters, comprising a green pigment having the following spectral characteristics:

when a coating film is formed so that the spectral transmittance at the maximum transmission wavelength is 80%,

the transmittance at a wavelength of 555nm is more than 45%,

t (505nm)/T (555nm), which is the ratio of the transmittance at a wavelength of 505nm to the transmittance at a wavelength of 555nm, is 1.40 or more, the half-value width is 80nm or less,

the green pigment is zinc chloride bromide phthalocyanine,

the average bromine number in 1 molecule of the brominated zinc chloride phthalocyanine is more than 7 times of the chlorine number,

further contains a yellow pigment, and the yellow pigment,

the maximum transmission wavelength in the coating film is in a range of 515nm to 530 nm.

2. The pigment composition for color filters according to claim 1, wherein the green pigment is zinc phthalocyanine bromide containing, in 1 molecule, on average 13 or more and 15 or less bromides and on average 1 or more and 3 or less chlorines.

3. A color filter comprising the pigment composition for color filters according to claim 1 or 2.