JP2012082282A - Pigment dispersant, red pigment dispersion for color filter, red resin composition for color filter, color filter, and liquid crystal display device - Google Patents

Abstract

（式（１）において、ｎは１〜１６の整数、ｍは１〜１６の整数である。）
【選択図】なしThe present invention provides a pigment dispersant, a red pigment dispersion for a color filter, and a red resin composition for a color filter, which can obtain a red colored layer having excellent dispersion stability and excellent contrast of PR254.
A pigment dispersant represented by the following general formula (1), a pigment dispersion containing the pigment dispersant, and a red resin composition for a color filter.

(In Formula (1), n is an integer of 1-16, m is an integer of 1-16.)
[Selection figure] None

Description

  The present invention relates to a pigment dispersant, a pigment dispersion using the pigment dispersant, a red resin composition for a color filter using the pigment dispersion, a color filter formed using the resin composition, and the color The present invention relates to a liquid crystal display device having a filter.

In recent years, with the development of personal computers, particularly portable personal computers, the demand for liquid crystal displays has increased. In recent years, the penetration rate of home-use liquid crystal televisions has been increasing, and the market for liquid crystal displays is expanding. Furthermore, with regard to the performance of the liquid crystal display, further improvement in image quality such as improvement in contrast and color reproducibility and reduction in power consumption are strongly desired.
Under such circumstances, there is an increasing demand for higher brightness, higher contrast, and improved color reproducibility even in a color filter having a function of displaying liquid crystal displays in color.

Here, the color filter used in the liquid crystal display device generally defines a transparent substrate, a colored layer formed on the transparent substrate, which is composed of colored patterns of three primary colors of red, green, and blue, and each colored pattern. As described above, the light shielding portion is formed on the transparent substrate.
As a method for forming such a colored layer, a pigment dispersion method, a dyeing method, an electrodeposition method, a printing method, and the like are known. Among these, from the viewpoint of spectral characteristics, durability, pattern shape, accuracy, etc., a pigment dispersion method having excellent characteristics on average is most widely adopted.

  In general, a color filter in which a pigment is dispersed has a problem that the degree of polarization controlled by the liquid crystal is disturbed due to light scattering by the pigment. That is, since light leaks when light must be blocked (OFF state) or transmitted light attenuates when light must be transmitted (ON state), display devices in the ON state and the OFF state There is a problem that the upper luminance ratio (contrast ratio) is low.

In recent years, there has been a growing demand for higher luminance of color filters for television applications due to reduced power consumption of backlights and LED backlight characteristics.
Currently, as a LED for a backlight, a three-color LED has a small cost merit, so a pseudo white LED (a combination of a blue LED and a yellow phosphor (B-) is formed by applying a phosphor on the surface of a blue LED. YAG) or a combination of a blue LED, a red phosphor and a green phosphor (B-RG)). When such a white LED backlight is used, since the red light emission intensity is weak compared to the blue light emission intensity, the transmittance of the red colored layer is lowered, and thus the red colored layer needs to have high brightness. It has been.

C. I. Pigment Red 254 is a red pigment having a high transmittance. I. Higher brightness than the pigment red 177 can be realized. However, PR254 has a problem that the contrast tends to be low because it is not sufficiently dispersed only by dispersing with an ordinary dispersant.
In order to realize a high contrast of the color filter, it has been studied to refine the pigment contained in the colored layer. As an attempt to refine the pigment, a pigment blend in which a pigment and a pigment derivative having a structure similar to the pigment are combined is used. C. I. For pigment red 254, an attempt has been made to combine a diketopyrrolopyrrole pigment derivative into which a substituent such as sulfonamide is introduced with a diketopyrrolopyrrole pigment as a pigment dispersant (for example, Patent Document 1). However, diketopyrrolopyrrole pigment derivatives such as those described above are C.I. I. When combined with CI Pigment Red 254, the pigment can be finely dispersed. However, the diketopyrrolopyrrole pigment derivative as described above is a color on the blue side of the diketopyrrolopyrrole pigment mixed by the influence of the electron withdrawing group. In many cases, the red colored layer using a combination of the diketopyrrolopyrrole pigment derivative as described above is C.I. I. Since a compound having absorption at the transmission wavelength of Pigment Red 254 is added, there is a problem in that the luminance is lowered. According to the recent trend of higher brightness in development, pigment derivatives that lower brightness cannot be used. Furthermore, a further improvement in contrast has been desired over the contrast obtained with diketopyrrolopyrrole pigment derivatives.

  On the other hand, in Patent Document 2, a pigment dispersant containing a triazine skeleton having a sulfonic acid group is used for the purpose of obtaining an ink having excellent non-aggregation, non-crystallinity, and fluidity, and excellent gloss and brightness of a coating film. It is disclosed. However, as shown in a comparative example to be described later, in the technique disclosed in Patent Document 2, C.I. I. When applied to CI Pigment Red 254, the dispersion stability is insufficient. In Patent Document 3, C.I. I. An example is described in which a dianthraquinone triazine skeleton-containing dye having a sulfonic acid group is combined with a diketopyrrolopyrrole pigment derivative having a sulfone group introduced when Pigment Red 254 is dispersed. In Patent Document 3, as a comparative example, C.I. I. When the pigment red 254 pigment is dispersed, when a dianthraquinone triazine skeleton-containing dye having a sulfonic acid group is used as a dye having a sulfonic acid group without using a diketopyrrolopyrrole pigment derivative having a sulfone group introduced, pigment dispersibility, It has been shown that the dispersion stability is poor.

JP 2001-214085 A Japanese Patent Laid-Open No. 10-265697 JP 2006-265528 A

  The present invention has been made under such circumstances. I. Pigment Red 254, a pigment dispersion, a red pigment dispersion for color filters, and a red resin composition for color filters, which are excellent in dispersibility and dispersion stability of Pigment Red 254, and can provide a red colored layer with excellent contrast without lowering brightness. An object of the present invention is to provide a color filter formed using the resin composition and a liquid crystal display device having the color filter.

As a result of intensive studies to achieve the above object, the present inventors have found that C.I. I. When dispersing Pigment Red 254, when combined with a monoanthraquinone triazine skeleton-containing compound having both a sulfonic acid group and a carboxyl group as a pigment dispersant, the pigment dispersibility and pigment dispersion stability become excellent, and the contrast is excellent. It was found that a red colored layer was obtained.
The present invention has been completed based on such findings.

  The pigment dispersant according to the present invention is represented by the following general formula (1).

（式（１）において、ｎは１〜１６の整数、ｍは１〜１６の整数である。）

(In Formula (1), n is an integer of 1-16, m is an integer of 1-16.)

  The red pigment dispersion for a color filter according to the present invention is a pigment dispersion containing a pigment, a pigment dispersant, and a solvent. I. Pigment Red 254, and the pigment dispersant includes the pigment dispersant represented by the general formula (1) according to the present invention.

  In the red pigment dispersion for a color filter according to the present invention, the pigment dispersant further includes a polymer dispersant which is a block copolymer containing a tertiary amine salt or a quaternary ammonium salt. . I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

  In the red pigment dispersion for a color filter according to the present invention, as the polymer dispersant, a repeating unit (1) represented by the following general formula (I) and a repeating unit represented by the following general formula (II): (2) and a polymer dispersant that is a block copolymer in which at least a part of the amino group of the repeating unit (1) and an organic acid compound form a salt. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

［式（Ｉ）及び式（ＩＩ）中、Ｒ^１は、水素原子又はメチル基、Ｒ^２及びＲ^３は、それぞれ独立に水素原子又は炭素数１〜８のアルキル基、Ａは、炭素数１〜８のアルキレン基、−[ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−Ｏ]_ｘ−ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−又は−[（ＣＨ_２）_ｙ−Ｏ]_ｚ−（ＣＨ_２）_ｙ−で示される２価の基、Ｒ^４は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−[ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−Ｏ]_ｘ−Ｒ^８又は−[（ＣＨ_２）_ｙ−Ｏ]_ｚ−Ｒ^８で示される１価の基である。Ｒ^６及びＲ^７は、それぞれ独立に水素原子又はメチル基であり、Ｒ^８は、水素原子、あるいは炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−ＣＨＯ、−ＣＨ_２ＣＨＯ、又は−ＣＨ_２ＣＯＯＲ^９で示される１価の基であり、Ｒ^９は水素原子又は炭素数が１〜５のアルキル基である。上記アルキル基、アルケニル基、アラルキル基、アリール基はそれぞれ置換基を有していても良い。
ｘは１〜１８の整数、ｙは１〜５の整数、ｚは１〜１８の整数を示す。ｍは３〜２００の整数、ｎは１０〜２００の整数を示す。］

[In Formula (I) and Formula (II), R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and A is a carbon atom having 1 carbon atom. To 8 alkylene groups, — [CH (R ⁶ ) —CH (R ⁷ ) —O] _x —CH (R ⁶ ) —CH (R ⁷ ) — or — [(CH ₂ ) _y —O] _z — ( CH _{2) y} - ₂ monovalent group represented by, ^{R 4} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl ^{group, - [CH (R 6)} -CH It is a monovalent group represented by (R ⁷ ) —O] _x —R ⁸ or — [(CH ₂ ) _y —O] _z —R ⁸ . R ⁶ and R ⁷ are each independently a hydrogen atom or a methyl group, and R ⁸ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, It is a monovalent group represented by —CHO, —CH ₂ CHO, or —CH ₂ COOR ⁹ , and R ⁹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group, alkenyl group, aralkyl group, and aryl group each may have a substituent.
x is an integer of 1 to 18, y is an integer of 1 to 5, and z is an integer of 1 to 18. m represents an integer of 3 to 200, and n represents an integer of 10 to 200. ]

  In the red pigment dispersion for a color filter according to the present invention, the blending ratio of the pigment dispersant represented by the general formula (1) is 0.5 to 25 parts by weight with respect to 100 parts by weight of the pigment. But C.I. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

  In the red pigment dispersion for a color filter according to the present invention, the organic acid compound in the polymer dispersant is selected from the group consisting of organic acids represented by the following general formula (III) and the following general formula (IV) C. is at least one selected from C.I. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

［式（ＩＩＩ）及び式（ＩＶ）中、Ｒ^ａ及びＲ^ａ’はそれぞれ独立に、水素原子、水酸基、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅ、又は−Ｏ−Ｒ^ａ’’で示される１価の基であり、Ｒ^ａ及びＲ^ａ’のいずれかは炭素原子を含む。Ｒ^ａ’’は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅで示される１価の基である。
Ｒ^ｂは、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅ、又は−Ｏ−Ｒ^ｂ’で示される１価の基である。Ｒ^ｂ’は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、又は−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅで示される１価の基である。
Ｒ^ｃ及びＲ^ｄは、それぞれ独立に水素原子又はメチル基であり、Ｒ^ｅは、水素原子、あるいは炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−ＣＨＯ、−ＣＨ_２ＣＨＯ、−ＣＯ−ＣＨ＝ＣＨ_２、−ＣＯ−Ｃ（ＣＨ_３）＝ＣＨ_２又は−ＣＨ_２ＣＯＯＲ^ｆで示される１価の基であり、Ｒ^ｆは水素原子又は炭素数１〜５のアルキル基である。
Ｒ^ａ、Ｒ^ａ’、及びＲ^ｂにおいて、アルキル基、アルケニル基、アラルキル基、アリール基はそれぞれ、置換基を有していてもよい。
ｓは１〜１８の整数、ｔは１〜５の整数、ｕは１〜１８の整数を示す。］

[In Formula (III) and Formula (IV), R ^a and R ^{a ′} are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, or an aryl group. 1 represented by the group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e , or —O—R ^{a ″.} the valence of the group, one of R ^a and R ^{a 'comprises} a carbon atom. R ^{a ″} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e. ,-[(CH ₂ ) _t —O] _u —R ^e .
R ^b is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e or a monovalent group represented by —O—R ^{b ′} . R ^{b ′} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or _- it is a monovalent group represented by _{[(CH 2) t -O]} u -R e.
R ^c and R ^d are each independently a hydrogen atom or a methyl group, and R ^e is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, _{-CHO, -CH 2 CHO, -CO-} CH = CH 2, a monovalent group represented by _{-CO-C (CH 3) =} CH 2 or _-CH 2 COOR ^{f, R f} is hydrogen or C It is an alkyl group of formula 1-5.
In R ^a , R ^{a ′} , and R ^b , each of the alkyl group, alkenyl group, aralkyl group, and aryl group may have a substituent.
s is an integer of 1 to 18, t is an integer of 1 to 5, and u is an integer of 1 to 18. ]

  The red resin composition for a color filter according to the present invention contains the red pigment dispersion for the color filter and a curable binder component.

The present invention also provides a color filter comprising at least a transparent substrate and a colored layer provided on the transparent substrate, wherein at least one of the colored layers cures the red resin composition for a color filter of the present invention. There is provided a color filter having a colored layer formed.
Furthermore, the present invention provides a liquid crystal display device comprising the color filter, a counter substrate, and a liquid crystal layer formed between the color filter and the counter substrate.

  According to the present invention, C.I. I. Pigment Red 254, a pigment dispersion, a red pigment dispersion for color filters, and a red resin composition for color filters, which are excellent in dispersibility and dispersion stability of Pigment Red 254, and can provide a red colored layer with excellent contrast without lowering brightness. In addition, a color filter formed using the resin composition and a liquid crystal display device having the color filter can be provided.

It is the schematic which shows an example of the color filter of this invention. It is the schematic which shows an example of the liquid crystal display device of this invention.

Hereinafter, the pigment dispersant, the red pigment dispersion for the color filter, the red resin composition for the color filter, the color filter, and the liquid crystal display device of the present invention will be described in order.
In the present invention, light includes electromagnetic waves having wavelengths in the visible and invisible regions, and further includes radiation, and the radiation includes, for example, microwaves and electron beams. Specifically, it means an electromagnetic wave having a wavelength of 5 μm or less and an electron beam. In the present invention, (meth) acryl means either acryl or methacryl, and (meth) acrylate means either acrylate or methacrylate.
In addition, C.I. I. Pigment Red may be abbreviated as “PR”.

1. Pigment Dispersant The pigment dispersant according to the present invention is represented by the following general formula (1).

（式（１）において、ｎは１〜１６の整数、ｍは１〜１６の整数である。）

(In Formula (1), n is an integer of 1-16, m is an integer of 1-16.)

  C. I. When pigment red 254 is dispersed, a diketopyrrolopyrrole pigment derivative having a sulfonic acid group introduced when a compound containing a monoanthraquinone triazine skeleton having both a sulfonic acid group and a carboxyl group according to the present invention is combined as a pigment dispersant. It has been found that a red colored layer with excellent contrast can be obtained without lowering the luminance, without using a pigment, because it has excellent pigment dispersibility and pigment dispersion stability.

In the present invention, by adopting the above specific structure, C.I. I. The effect of improving the dispersibility and dispersion stability of CI Pigment Red 254 and producing a red colored layer with excellent contrast without lowering the brightness is not yet elucidated, but is estimated as follows. Is done.
By having a specific monoanthraquinone triazine skeleton, it shows a specific hue of yellow to red, and does not decrease the luminance, and is pigmentary (fastness to solvents, etc.) compared to a dianthraquinone skeleton having two anthraquinone skeletons ) Is considered to improve the affinity for solvents, resins and pigments.
In addition, by having both a sulfonic acid group and a carboxyl group, it can be adjusted so as not to impair the affinity for an organic solvent as compared with the case of containing only a large number of sulfonic acid groups, and effects such as a buffering action of the carboxyl group Is presumed to contribute to dispersibility.

  In the above general formula (1), the sulfonic acid group and the carboxyl group are each substituted with a phenyl group instead of anthraquinone. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

  In the general formula (1), the sulfonic acid group is preferably 1 to 10 in one molecule, more preferably 1 to 5 in one molecule, and particularly 1 to 2 in one molecule. That C.I. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

  On the other hand, in the general formula (1), the carboxyl group is preferably 1 to 10 in one molecule, more preferably 1 to 5 in one molecule, and particularly 1 to 2 in one molecule. There are C.I. I. It is preferable from the viewpoint of improving dispersibility, dispersion stability, and contrast of CI Pigment Red 254.

2. Red pigment dispersion for color filter The red pigment dispersion for a color filter according to the present invention is a pigment dispersion containing a pigment, a pigment dispersant, and a solvent. I. Pigment Red 254, and the pigment dispersant includes the pigment dispersant represented by the general formula (1) according to the present invention.

  The red pigment dispersion for a color filter according to the present invention includes C.I. I. Pigment Red 254 is dispersed with a pigment dispersant containing the pigment dispersant represented by Formula (1) according to the present invention. I. A red colored layer having excellent dispersibility and dispersion stability of CI Pigment Red 254 and excellent contrast can be obtained.

The red pigment dispersion for a color filter according to the present invention includes C.I. I. Pigment Red 254, a pigment dispersant containing a pigment dispersant represented by the general formula (1) according to the present invention, and a solvent are contained as essential components. It may contain components.
Hereinafter, each component of the red pigment dispersion of the present invention will be described in detail.

(Pigment)
C. used in the present invention. I. Pigment Red 254 has a structure represented by the following chemical formula.

  C. used in the present invention. I. Pigment Red 254 can be produced by a known method such as a recrystallization method or a solvent salt milling method. In addition, commercially available C.I. I. Pigment Red 254 (for example, Ciba Specialty Chemicals Irgafore Red B-CF) may be used after being milled.

  The red pigment dispersion for color filter of the present invention may further contain other pigments as long as the chromaticity required for the specification can be achieved and the effects of the present invention are not impaired. Other pigments include, for example, other red pigments and yellow pigments from the viewpoint of achieving a specific color necessary for the red colored layer of the color filter. Furthermore, other pigments such as orange may be contained.

  Other red pigments include, for example, C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 4, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 8, C.I. Pigment Red 9, C.I. Pigment Red 10, C.I. Pigment Red 11, C.I. Pigment Red 12, C.I. Pigment Red 14, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 17, C.I. Pigment Red 18, C.I. Pigment Red 19, C.I. Pigment Red 21, C.I. Pigment Red 22, C.I. Pigment Red 23, C.I. Pigment Red 30, C.I. Pigment Red 31, C.I. Pigment Red 32, C.I. Pigment Red 37, C.I. Pigment Red 38, C.I. Pigment Red 40, C.I. Pigment Red 41, C.I. Pigment Red 42, C.I. Pigment Red 48: 1, C.I. Pigment Red 48: 2, C.I. Pigment Red 48: 3, C.I. Pigment Red 48: 4, C.I. Pigment Red 49: 1, C.I. Pigment Red 49: 2, C.I. Pigment Red 50: 1, C.I. Pigment Red 52: 1, C.I. Pigment Red 53: 1, C.I. Pigment Red 57, C.I. Pigment Red 57: 1, C.I. Pigment Red 57: 2, C.I. Pigment Red 58: 2, C.I. Pigment Red 58: 4, C.I. Pigment Red 60: 1, C.I. Pigment Red 63: 1, C.I. Pigment Red 63: 2, C.I. Pigment Red 64: 1, C.I. Pigment Red 81: 1, C.I. Pigment Red 83, C.I. Pigment Red 88, C.I. Pigment Red 90: 1, C.I. Pigment Red 97, C.I. Pigment Red 101, C.I. Pigment Red 102, C.I. Pigment Red 104, C.I. Pigment Red 105, C.I. Pigment Red 106, C.I. Pigment Red 108, C.I. Pigment Red 112, C.I. Pigment Red 113, C.I. Pigment Red 114, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 144, C.I. Pigment Red 146, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 151, C.I. Pigment Red 166, C.I. Pigment Red 168, C.I. Pigment Red 170, C.I. Pigment Red 171, C.I. Pigment Red 172, C.I. Pigment Red 174, C.I. Pigment Red 175, C.I. Pigment Red 176, C.I. Pigment Red 177, C.I. Pigment Red 178, C.I. Pigment Red 179, C.I. Pigment Red 180, C.I. Pigment Red 185, C.I. Pigment Red 187, C.I. Pigment Red 188, C.I. Pigment Red 190, C.I. Pigment Red 193, C.I. Pigment Red 194, C.I. Pigment Red 202, C.I. Pigment Red 206, C.I. Pigment Red 207, C.I. Pigment Red 208, C.I. Pigment Red 209, C.I. Pigment Red 215, C.I. Pigment Red 216, C.I. Pigment Red 220, C.I. Pigment Red 224, C.I. Pigment Red 226, C.I. Pigment Red 242, C.I. Pigment Red 243, C.I. Pigment Red 245, C.I. Pigment Red 255, C.I. Pigment Red 264, C.I. And CI Pigment Red 265.

Examples of yellow pigments include C.I. Pigment Yellow 150 and its derivative pigments, C.I. Pigment Yellow 138, and C.I. It is preferably at least one selected from the group consisting of I. Pigment Yellow 139.
Here, C.I. I. Pigment Yellow 150 derivative pigments specifically include mono-, di-, tri- and tetraanions of azo compounds according to the following chemical formula or one of their tautomeric structures that act as hosts for at least one guest compound And metal complexes corresponding to Li, Cs, Mg, Cd, Co, Al, Cr, Sn, Pb, particularly preferably Na, K, Ca, Sr, Ba, Zn, Fe, Ni, Cu, Mn and La Can be mentioned.

［上記化学式中、ＲおよびＲ’は、独立して、ＯＨ、ＮＨ_２、ＮＨ−ＣＮ、アシルアミノまたはアリールアミノであり、そしてＲ^ａおよびＲ^ａ’は、独立して、−ＯＨまたは−ＮＨ_２である］

[Wherein R and R ′ are independently OH, NH ₂ , NH—CN, acylamino or arylamino, and R ^a and R ^a ′ are independently —OH or —NH ₂ Is]

  These derivative pigments are disclosed in JP 2001-354869, JP 2005-325350, JP 2007-25687, JP 2007-23287, JP 2007-23288, and JP 2008. It can be obtained by referring to Japanese Patent No. -24927.

  Among these, when it is contained as other pigments, C.I. I. Pigment red 177, C.I. I. Pigment red 242, and C.I. I. It is preferable to include one or more pigments selected from the group consisting of CI Pigment Yellow 150 and its derivative pigments from the viewpoint of improving contrast while achieving a specific color required for the red colored layer of the color filter.

C. used in the present invention. I. The average primary particle size of the pigment such as CI Pigment Red 254 is not particularly limited as long as it can produce a desired color when it is used as a color layer of a color filter. It is preferably in the range of 10 to 70 nm, and more preferably in the range of 10 to 50 nm. When the average primary particle size of the pigment is within the above range, the liquid crystal display device manufactured using the red pigment dispersion for the color filter of the present invention and the resin composition should have high contrast and high quality. Can do.
In addition, the average particle diameter of the pigment can be obtained by a method of directly measuring the size of primary particles from an electron micrograph. Specifically, the minor axis diameter and major axis diameter of each primary particle were measured, and the average was taken as the particle diameter of the particle. Next, for 100 or more particles, the volume (weight) of each particle was obtained by approximating the obtained particle size to a rectangular parallelepiped, and the volume average particle size was obtained and used as the average particle size. The same result can be obtained regardless of whether the electron microscope is a transmission type (TEM) or a scanning type (SEM).

  In the red pigment dispersion for color filter of the present invention, C.I. I. The content of Pigment Red 254 may be adjusted as appropriate and is not particularly limited. Usually, C.I. I. The content of the pigment containing Pigment Red 254 is preferably in the range of 5 to 40% by weight, more preferably 10 to 20% by weight, based on the total amount of the red pigment dispersion for color filters.

(Pigment dispersant)
In the present invention, as the pigment dispersant, the pigment dispersant represented by the general formula (1) is used as an essential component, and further, for example, cationic, anionic, nonionic, amphoteric, silicone-based, fluorine-based A pigment dispersant composed of a surfactant such as the above may be used in combination. From the viewpoint of improving contrast, it is preferable to use a combination of a polymer surfactant (polymer dispersant).

  Examples of the polymer dispersant include (co) polymers of unsaturated carboxylic acid esters such as polyacrylic acid esters; (partial) amine salts of (co) polymers of unsaturated carboxylic acid such as polyacrylic acid; (Partial) ammonium salts and (partial) alkylamine salts; (co) polymers of hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing polyacrylates and their modified products; polyurethanes; unsaturated polyamides; polysiloxanes Long chain polyaminoamide phosphates; amides obtained by the reaction of poly (lower alkyleneimine) and free carboxyl group-containing polyester, salts thereof, and the like.

  Examples of the pigment dispersant used in the present invention include a block copolymer type or graft copolymer (comb type) type polymer dispersant in which a pigment adsorption site and a solvent affinity site are functionally separated in the molecule. From the viewpoints of stability and dispersion stability.

  Among them, the polymer dispersant used in combination with the pigment dispersant represented by the general formula (1) in the present invention is preferably a block copolymer containing a tertiary amine salt or a quaternary ammonium salt. . In such a block copolymer, a block portion containing a tertiary amine salt or a quaternary ammonium salt is adsorbed to the pigment and the pigment dispersant represented by the general formula (1), and the tertiary amine salt is absorbed. Or since the block part which does not contain a quaternary ammonium salt has solubility with respect to a solvent, the dispersibility of a pigment can be improved. In particular, in the present invention, when the pigment dispersant represented by the above general formula (1) and a pigment dispersant composed of a salt type block copolymer are used in combination, C.I. I. The pigment red 254 can be miniaturized and the contrast can be improved. By using a pigment dispersant made of a block copolymer, the size of the pigment adsorbing part and the solvent-soluble part can be designed smaller than when a graft polymer type pigment dispersant is used. Get higher.

Examples of the tertiary amine salt include a salt formed at a tertiary amine moiety such as dimethylaminoethyl acrylate, which is a unit forming a block copolymer, with an acid such as a phosphoric acid compound or a sulfonic acid compound. In addition, examples of the quaternary ammonium salt include a quaternary ammonium salt such as dimethylaminoethyl acrylate, which is a unit that forms a block copolymer, at a tertiary amine moiety by an allyl halide and / or an aralkyl halide. It is done.
The block portion containing a tertiary amine salt or a quaternary ammonium salt may contain an amine that does not form a salt.

  The amount of the tertiary amine salt or quaternary ammonium salt contained in the copolymer is preferably 1 to 50% in terms of the number of repeating units with respect to the total number of repeating units of the block copolymer. It is preferable that it is 1 to 20%.

  Examples of the main chain structure of the polymer include (meth) acrylic resins and styrene resins. Among these, a (meth) acrylic resin is preferable in that it easily synthesizes a block copolymer.

  The weight average molecular weight Mw of the block copolymer containing a tertiary amine salt or a quaternary ammonium salt used in the present invention is preferably in the range of 500 to 20000, and preferably in the range of 1000 to 15000. More preferably, it is still more preferably in the range of 3000-12000. By being within the above range, it becomes possible to achieve both wettability and dispersion stability with respect to a pigment in the initial stage of dispersion in which the pigment is uniformly dispersed. Here, the weight average molecular weight can be determined as a standard polystyrene equivalent value by gel permeation chromatography (GPC).

  The pigment dispersant used in the present invention has, among other things, a repeating unit (1) represented by the following general formula (I) and a repeating unit (2) represented by the following general formula (II), Furthermore, it is a block copolymer in which at least a part of the amino group of the repeating unit (1) and an organic acid compound and / or a halogenated hydrocarbon form a salt, so that a coating film with particularly improved contrast is produced. It is preferable from the point that it becomes possible.

［式（Ｉ）及び式（ＩＩ）中、Ｒ^１は、水素原子又はメチル基、Ｒ^２及びＲ^３は、それぞれ独立に水素原子又は炭素数１〜８のアルキル基、Ａは、炭素数１〜８のアルキレン基、−[ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−Ｏ]_ｘ−ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−又は−[（ＣＨ_２）_ｙ−Ｏ]_ｚ−（ＣＨ_２）_ｙ−で示される２価の基、Ｒ^４は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−[ＣＨ（Ｒ^６）−ＣＨ（Ｒ^７）−Ｏ]_ｘ−Ｒ^８又は−[（ＣＨ_２）_ｙ−Ｏ]_ｚ−Ｒ^８で示される１価の基である。Ｒ^６及びＲ^７は、それぞれ独立に水素原子又はメチル基であり、Ｒ^８は、水素原子、あるいは炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−ＣＨＯ、−ＣＨ_２ＣＨＯ、又は−ＣＨ_２ＣＯＯＲ^９で示される１価の基であり、Ｒ^９は水素原子又は炭素数が１〜５のアルキル基である。上記アルキル基、アルケニル基、アラルキル基、アリール基はそれぞれ置換基を有していても良い。
ｘは１〜１８の整数、ｙは１〜５の整数、ｚは１〜１８の整数を示す。ｍは３〜２００の整数、ｎは１０〜２００の整数を示す。］

[In Formula (I) and Formula (II), R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and A is a carbon atom having 1 carbon atom. To 8 alkylene groups, — [CH (R ⁶ ) —CH (R ⁷ ) —O] _x —CH (R ⁶ ) —CH (R ⁷ ) — or — [(CH ₂ ) _y —O] _z — ( CH _{2) y} - ₂ monovalent group represented by, ^{R 4} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl ^{group, - [CH (R 6)} -CH It is a monovalent group represented by (R ⁷ ) —O] _x —R ⁸ or — [(CH ₂ ) _y —O] _z —R ⁸ . R ⁶ and R ⁷ are each independently a hydrogen atom or a methyl group, and R ⁸ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, It is a monovalent group represented by —CHO, —CH ₂ CHO, or —CH ₂ COOR ⁹ , and R ⁹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group, alkenyl group, aralkyl group, and aryl group each may have a substituent.
x is an integer of 1 to 18, y is an integer of 1 to 5, and z is an integer of 1 to 18. m represents an integer of 3 to 200, and n represents an integer of 10 to 200. ]

  The pigment dispersant comprising such a specific salt-type block copolymer includes the structural unit (1) represented by the general formula (I) and the structural unit (2) represented by the general formula (II). And a salt-forming block is formed by a salt-type block copolymer in which the amino group of the structural unit (1) and the organic acid compound and / or halogenated hydrocarbon form a salt. The structural unit (1) has particularly strong adsorptivity to the pigment and the pigment dispersant represented by the general formula (1), while the structural unit (2) has solubility in a solvent. When such a polymer dispersant is used in combination with the pigment dispersant represented by the general formula (1), C.I. I. While the pigment red 254 is being refined, the pigment dispersant represented by the general formula (1) and the polymer dispersant are appropriately adsorbed on the surface of the refined and exposed pigment, thereby stabilizing the pigment in the solvent. C. I. It is presumed that the pigment red 254 can be more uniformly refined. As a result, it is estimated that a coating film with improved contrast can be obtained.

<Block copolymer>
The block copolymer has a repeating unit (1) represented by the general formula (I) and a repeating unit (2) represented by the general formula (II).
In the said general formula (I), R < ¹ > shows a hydrogen atom or a methyl group, R < ² > and R < ³ > show a hydrogen atom or a C1-C8 alkyl group each independently. Here, the alkyl group having 1 to 8 carbon atoms may be linear, branched or cyclic. Examples of such alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, various pentyl groups, various hexyl groups, and various octyl groups. Group, cyclopentyl group, cyclohexyl group, cyclooctyl group and the like. Among these, a methyl group and an ethyl group are preferable.
In the present invention, R ² and R ³ may be the same as or different from each other.

A is an alkylene group having 1 to 8 carbon atoms, * — [CH (R ⁶ ) —CH (R ⁷ ) —O] _x —CH (R ⁶ ) —CH (R ⁷ ) — **, or * — [(CH ₂ ) _y —O] _z — (CH ₂ ) _y — ** is a divalent group. Here, * represents a linking site on the ester bond side, and ** represents a linking site on the amino group side. The alkylene group having 1 to 8 carbon atoms may be linear or branched. For example, a methylene group, an ethylene group, a trimethylene group, a propylene group, various butylene groups, various pentylene groups, various kinds. Hexylene group and various octylene groups.
R ⁶ and R ⁷ are each independently a hydrogen atom or a methyl group.
x is an integer of 1 to 18, preferably an integer of 1 to 4, more preferably an integer of 1 to 2, and y is an integer of 1 to 5, preferably an integer of 1 to 4, more preferably 2 or 3. is there. z is an integer of 1-18, preferably an integer of 1-4, more preferably an integer of 1-2. In the present invention, if x, y, and z are within the above ranges, the color filter pigment dispersion of the present invention has excellent pigment dispersibility.
As said A, a C1-C8 alkylene group is preferable and a methylene group and ethylene group are more preferable. If the carbon number is in the range of 1 to 8, the dispersibility of the pigment can be kept good.

In the general formula (II), R ⁴ represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ⁶ ) —CH (R ⁷ ) —. O] _x -R ⁸ or - indicates a _{[(CH 2) y -O]} z -R 8.
The alkyl group having 1 to 18 carbon atoms may be linear, branched or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group. , Sec-butyl group, tert-butyl group, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, various dodecyl groups, various tetradecyl groups, various hexadecyl groups, various octadecyl groups, cyclopentyl groups, cyclohexyl groups, cyclohexane Examples include an octyl group, a cyclododecyl group, a bornyl group, an isobornyl group, a dicyclopentanyl group, an adamantyl group, and a lower alkyl group-substituted adamantyl group.
The alkenyl group having 2 to 18 carbon atoms may be linear, branched or cyclic. Examples of such alkenyl groups include vinyl, allyl, propenyl, various butenyl, various hexenyl, various octenyl, various decenyl, various dodecenyl, various tetradecenyl, various hexadecenyl, various octadecenyl, A cyclopentenyl group, a cyclohexenyl group, a cyclooctenyl group, etc. can be mentioned. The position of the double bond of the alkenyl group is not limited, but from the viewpoint of the reactivity of the polymer obtained, it is preferable that there is a double bond at the terminal of the alkenyl group.

Examples of the aryl group which may have a substituent include a phenyl group, a biphenyl group, a naphthyl group, a tolyl group, and a xylyl group. 6-24 are preferable and, as for carbon number of an aryl group, 6-12 are more preferable.
Examples of the aralkyl group which may have a substituent include a benzyl group, a phenethyl group, a naphthylmethyl group, and a biphenylmethyl group. 7-20 are preferable and, as for carbon number of an aralkyl group, 7-14 are more preferable.
Examples of the substituent of the aromatic ring such as an aryl group and an aralkyl group include an alkenyl group, a nitro group, and a halogen atom in addition to a linear or branched alkyl group having 1 to 4 carbon atoms.
The preferred carbon number does not include the carbon number of the substituent.

R ⁶ and R ⁷ are the same as described above, and R ⁸ is a hydrogen atom or an optionally substituted alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, and an aralkyl group. , An aryl group, —CHO, —CH ₂ CHO, or —CH ₂ COOR ⁹ , wherein R ⁹ is a hydrogen atom or a linear, branched, or cyclic group having 1 to 5 carbon atoms. It is an alkyl group.
In the monovalent group represented by R ⁸ , the substituent that may be included is, for example, a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms, a halogen atom such as F, Cl, or Br. And so on.
The alkyl group having 1 to 18 carbon atoms of ^{R 8,} and alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group is as shown by the ^{R 4.}
In the above R ⁴ , x, y and z are as described in A above.
Moreover, R ⁴ in the repeating unit (2) represented by the general formula (II) may be the same as or different from each other.

In the present invention, as R ⁴ , it is preferable to use those having excellent solubility in the solvent described later, and specifically, it varies depending on the repeating units constituting the block copolymer. When the solvent is an ether alcohol acetate solvent, an ether solvent, an ester solvent or the like generally used as a solvent for a color filter, a methyl group, an ethyl group, an n-butyl group, 2- An ethylhexyl group, a benzyl group and the like are preferable. Moreover, when the said solvent is a thing with lower polarity, such as pentane and hexane, it is preferable to use a pentyl group, a hexyl group, a heptyl group, etc.
Here, the reason for setting R ⁴ in this way is that the repeating unit (2) containing R ⁴ has high solubility in the solvent, and the amino group of the repeating unit (1) This is because the dispersibility and stability of the pigment can be made particularly excellent when the salt-forming site formed by the organic acid compound described later has a high adsorptivity to the pigment.

Further, R ⁴ is substituted with a substituent such as an alkoxy group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, an isocyanate group, or a hydrogen bond-forming group as long as it does not interfere with the dispersion performance of the block copolymer. Alternatively, after the synthesis of the block copolymer, the substituent may be added by reacting with the compound having the substituent. Moreover, after synthesizing a block copolymer having these substituents, a compound having a functional group that reacts with the substituent and a polymerizable group may be reacted to add a polymerizable group. For example, adding a polymerizable group by reacting a block copolymer having a carboxyl group with glycidyl (meth) acrylate, or reacting a block copolymer having an isocyanate group with hydroxyethyl (meth) acrylate. Can do.

  The ratio m / n of the number of units m of the structural unit (1) and the number of units n of the structural unit (2) used in the present invention is preferably within the range of 0.01 to 1, preferably 0.05 to More preferably, it is in the range of 0.5. When the ratio m / n is within the above range, the adsorptivity to the pigment is good, the solubility with the solvent by the structural unit (2) is not lowered, and the dispersibility and stability of the pigment are lowered. There is nothing to do.

Regarding the molecular size of the block copolymer used in the present invention, the number m of the repeating unit (1) is an integer of 3 to 200, preferably an integer of 3 to 50. The number n of the repeating units (2) is an integer of 10 to 200, preferably an integer of 20 to 100, more preferably an integer of 20 to 70. In the present invention, when m and n are within the above ranges, the solvent-soluble part and the solvent-insoluble part act effectively, and the pigment dispersion for the color filter of the present invention has excellent pigment dispersibility. Can be.
Further, the weight average molecular weight Mw of the block copolymer is preferably in the range of 500 to 20000, more preferably in the range of 1000 to 15000, and further preferably in the range of 3000 to 12000. preferable. By being within the above range, it becomes possible to achieve both wettability and dispersion stability with respect to a pigment in the initial stage of dispersion in which the pigment is uniformly dispersed.

  The weight average molecular weight Mw is a value measured by GPC (gel permeation chromatography). For the measurement, HLC-8120GPC manufactured by Tosoh Corporation was used, the elution solvent was N-methylpyrrolidone to which 0.01 mol / liter of lithium bromide was added, and the polystyrene standard for calibration curve was Mw377400, 210500, 96000, 50400. , 206500, 10850, 5460, 2930, 1300, 580 (Easi PS-2 series manufactured by Polymer Laboratories) and Mw1090000 (manufactured by Tosoh Corporation), and TSK-GEL ALPHA-M × 2 (Tosoh Corporation) (Made by Co., Ltd.).

  The binding order of the block copolymer used in the present invention is not particularly limited as long as it has the repeating unit (1) and the repeating unit (2) and can stably disperse the pigment. However, it is preferable that the repeating unit (1) is bonded to only one end of the block copolymer. That is, the repeating unit (1) and the repeating unit (2) may be bonded in the order of repeating unit (1) -repeating unit (2), or repeating unit (1) -repeating unit. (2) -repeated unit (1) may be bonded in this order, or repeating unit (1) -repeating unit (2) may be bonded repeatedly, but in the present invention, However, those bonded in the order of repeating unit (1) -repeating unit (2) are preferred. The reason is that it is excellent in the adsorptivity with respect to a pigment, and also the aggregation of pigment dispersants using such a block copolymer can be effectively suppressed.

  In the case where two or more structural units (1) and structural units (2) are included, a block copolymer in which the structural units (1), the structural units (2 ′), and the structural units (2 ″) are combined in this order, A block copolymer bonded in the order of structural unit (1 ')-structural unit (1 ")-structural unit (2), or structural unit (1')-structural unit (1")-structural unit (2 ') -The block copolymer etc. which couple | bonded in order of the structural unit (2 ") may be sufficient.

<Organic acid compound>
An amino group contained in the structural unit (1) of the block copolymer having the structural unit (1) represented by the general formula (I) and the structural unit (2) represented by the general formula (II); Examples of the organic acid compound that forms a salt include an organic phosphoric acid compound having a structure represented by the following general formula (III) and / or an organic sulfonic acid compound having a structure represented by the above general formula (IV). It is done.

［式（ＩＩＩ）及び式（ＩＶ）中、Ｒ^ａ及びＲ^ａ’はそれぞれ独立に、水素原子、水酸基、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅ、又は−Ｏ−Ｒ^ａ’’で示される１価の基であり、Ｒ^ａ及びＲ^ａ’のいずれかは炭素原子を含む。Ｒ^ａ’’は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅで示される１価の基である。
Ｒ^ｂは、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅ、又は−Ｏ−Ｒ^ｂ’で示される１価の基である。Ｒ^ｂ’は、炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−［ＣＨ（Ｒ^ｃ）−ＣＨ（Ｒ^ｄ）−Ｏ］_ｓ−Ｒ^ｅ、又は−［（ＣＨ_２）_ｔ−Ｏ］_ｕ−Ｒ^ｅで示される１価の基である。
Ｒ^ｃ及びＲ^ｄは、それぞれ独立に水素原子又はメチル基であり、Ｒ^ｅは、水素原子、あるいは炭素数１〜１８のアルキル基、炭素数２〜１８のアルケニル基、アラルキル基、アリール基、−ＣＨＯ、−ＣＨ_２ＣＨＯ、−ＣＯ−ＣＨ＝ＣＨ_２、−ＣＯ−Ｃ（ＣＨ_３）＝ＣＨ_２又は−ＣＨ_２ＣＯＯＲ^ｆで示される１価の基であり、Ｒ^ｆは水素原子又は炭素数１〜５のアルキル基である。
Ｒ^ａ、Ｒ^ａ’、及びＲ^ｂにおいて、アルキル基、アルケニル基、アラルキル基、アリール基はそれぞれ、置換基を有していてもよい。
ｓは１〜１８の整数、ｔは１〜５の整数、ｕは１〜１８の整数を示す。］

[In Formula (III) and Formula (IV), R ^a and R ^{a ′} are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, or an aryl group. 1 represented by the group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e , or —O—R ^{a ″.} the valence of the group, one of R ^a and R ^{a 'comprises} a carbon atom. R ^{a ″} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e. ,-[(CH ₂ ) _t —O] _u —R ^e .
R ^b is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e or a monovalent group represented by —O—R ^{b ′} . R ^{b ′} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or _- it is a monovalent group represented by _{[(CH 2) t -O]} u -R e.
R ^c and R ^d are each independently a hydrogen atom or a methyl group, and R ^e is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, _{-CHO, -CH 2 CHO, -CO-} CH = CH 2, a monovalent group represented by _{-CO-C (CH 3) =} CH 2 or _-CH 2 COOR ^{f, R f} is hydrogen or C It is an alkyl group of formula 1-5.
In R ^a , R ^{a ′} , and R ^b , each of the alkyl group, alkenyl group, aralkyl group, and aryl group may have a substituent.
s is an integer of 1 to 18, t is an integer of 1 to 5, and u is an integer of 1 to 18. ]

  In the present invention, by using the organic acid compound and / or the halogenated hydrocarbon described later, the pigment dispersant can be made excellent in pigment dispersibility and stability. Furthermore, when an organic acid compound is used, the salt-forming site has high solubility in an aqueous alkali solution at the time of alkali development, so that it can be excellent in alkali developability. In particular, as the particle size of the pigment is increased to improve the contrast, a large amount of pigment dispersant is required, which may cause problems such as reduced alkali developability and increased residue. In the case where an organic acid compound is used, such problems can be reduced.

In the general formula (III), R ^a and R ^{a ′} are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, or — [ CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e , or —O—R ^{a ″} , R ^a and R ^a Any of ^' includes carbon atoms.

The alkyl group having 1 to 18 carbon atoms, the alkenyl group having 2 to 18 carbon atoms, the aryl group, and the aralkyl group are as described for R ⁴ . The position of the double bond of the alkenyl group is not limited, but from the viewpoint of reactivity, it is preferable that the alkenyl group has a double bond at the terminal.
The alkyl group or alkenyl group may have a substituent, and examples of the substituent include halogen atoms such as F, Cl, and Br, nitro groups, and the like.
In addition, examples of the substituent of the aromatic ring such as the aryl group and the aralkyl group include alkenyl groups, nitro groups, and halogen atoms in addition to linear or branched alkyl groups having 1 to 4 carbon atoms. .

R ^c and R ^d are each independently a hydrogen atom or a methyl group, and R ^e is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, or an aryl group. , —CHO, —CH ₂ CHO, —CO—CH═CH ₂ , —CO—C (CH ₃ ) ═CH ₂ or —CH ₂ COOR ^f , and R ^f is a hydrogen atom or It is a linear, branched or cyclic alkyl group having 1 to 5 carbon atoms.

In the monovalent group represented by R ^e, Examples of the substituent which may have, for example, linear 1 to 4 carbon atoms, branched or cyclic alkyl group, F, Cl, halogen atom such as Br And so on.
Alkyl group having 1 to 18 carbon atoms of the above ^{R e} is as shown by ^{R 4} above, an alkenyl group, an aralkyl group having 2 to 18 carbon atoms, an aryl group, said ^{R a} and R ^{a '} It is as shown in.

When R ^a and / or R ^{a ′} is —O—R ^{a ″} , it is an acidic phosphate ester. R ^a ″ is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R. ^e is a monovalent group represented by — [(CH ₂ ) _t —O] _u —R ^e .
The alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group is as shown by the above ^{R a} and R ^{a '.} In addition, when R ^{a ″} has an aromatic ring, it may have an appropriate substituent on the aromatic ring, for example, a linear or branched alkyl group having 1 to 4 carbon atoms.

In R ^a , R ^{a ′} and R ^{a ″} , s is an integer of 1 to 18, t is an integer of 1 to 5, and u is an integer of 1 to 18. s is preferably an integer of 1 to 4, more preferably an integer of 1 to 2, and t is preferably an integer of 1 to 4, more preferably 2 or 3. u is preferably an integer of 1 to 4, more preferably an integer of 1 to 2.

In the general formula (IV), R ^b is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —. _O] s ^-R _e, - shows a _{[(CH 2) t -O]} u -R e, or -O-R ^{b '.}
The alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group is as shown by the above ^{R a} and R ^{a '.}

When R ^b is —O—R ^b ′, it becomes an acidic sulfate. R ^b ′ is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e. ,-[(CH ₂ ) _t —O] _u —R ^e .
In R ^b and R ^b ′, each of the alkyl group, alkenyl group, aralkyl group, and aryl group may have a substituent.
The alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl ^{group, - [CH (R c)} -CH (R d) -O] s -R e, - [(CH ₂ ) _t— O] _u —R ^e is as described above for R ^a , R ^a and R ^{a ″} .
R ^c , R ^d, and R ^e are as described above for R ^a , R ^a, and R ^{a ″} .
In said ^Rb and ^Rb ', s is an integer of 1-18, t is an integer of 1-5, u is an integer of 1-18. Preferred s, t, and u are the same as R ^a , R ^{a ′,} and R ^{a ″} described above.

As the organic acid compound represented by the general formula (III), R ^a and R ^{a ′} in the general formula (III) each independently have a hydrogen atom, a hydroxyl group, a methyl group, an ethyl group, or a substituent. Aryl group or aralkyl group, vinyl group, allyl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or — [(CH ₂ ) _t —O] _u —R ^e or a monovalent group represented by —O—R ^{a ″} , one of R ^a and R ^{a ′} contains a carbon atom, and R ^{a ″} is a methyl group, ethyl Group, aryl group or aralkyl group which may have a substituent, vinyl group, allyl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or — [(CH ₂ ) and _{^{t -O] u -R e, R}} c and ^{R d} are each independently a hydrogen atom or a methyl group Ri, from the viewpoint of can be made of those ^{R e} is -CO-CH = CH ₂ or _{-CO-C (CH} 3) a = CH ₂ is excellent in pigment dispersibility.

Moreover, as an organic acid compound represented by general formula (IV), ^Rb in general formula (IV) is a methyl group, an ethyl group, the aryl group which may have a substituent, an aralkyl group, a vinyl group. , An allyl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or — [(CH ₂ ) _t —O] _u —R ^e , or —O—R ^{b ′} R ^{b ′} is a methyl group, an ethyl group, an aryl group or an aralkyl group optionally having a substituent, a vinyl group, an allyl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or — [(CH ₂ ) _t —O] _u —R ^e , wherein R ^c and R ^d are each independently a hydrogen atom or a methyl group, and R ^e In which —CO—CH═CH ₂ or —CO—C (CH ₃ ) ═CH ₂ has excellent pigment dispersibility It is preferable from the point which can be made.

Of these, organic acid compound represented by the general formula (III) and general formula ^{(IV), R} a, R ^{a 'and} / or R ^a'', and / or as ^{R b} and / or R ^b' From the viewpoint of pigment dispersibility, an aromatic ring is preferred. At least one of R ^a , R ^{a ′} and R ^{a ″} , or R ^b or R ^{b ′} , an aryl group or aralkyl group which may have a substituent, more specifically, a benzyl group, A phenyl group, a tolyl group, a naphthyl group, and a biphenyl group are preferable from the viewpoint of pigment dispersibility. In the general formula (III), when one of R ^a and R ^{a ′} has an aromatic ring, the other of R ^a and R ^{a ′} is preferably a hydrogen atom or a hydroxyl group.

Further, from the viewpoint of heat resistance and chemical resistance, particularly alkali resistance, the organic acid compounds represented by the general formula (III) and the general formula (IV) include carbon (P) and sulfur (S). A compound in which atoms are directly bonded is preferable, and R ^a and R ^{a ′} each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl A monovalent group represented by a group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e , R ^a and Any of R ^{a ′} preferably contains a carbon atom. R ^b is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e. , — [(CH ₂ ) _t —O] _u —R ^e is preferably a monovalent group.

The organic acid compound represented by the general formula (III) and general formula ^{(IV), R} a, R ^{a 'and} / or R ^a'', and / or as ^{R b} and / or R ^b' Has a polymerizable group, that is, a vinyl group, an allyl group, or — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or — [(CH ₂ ) _t —O] _u. It is preferable that -R ^e and R ^e is -CO-CH = CH ₂ or -CO-C (CH ₃ ) = CH ₂ , especially R ^a , R ^{a ′} and / or R ^{a ′. '} And / or R ^b and / or R ^b' are preferably vinyl, allyl, 2-methacryloyloxyethyl, or 2-acryloyloxyethyl.
In such a case, the above-mentioned polymerizable groups and / or the above-mentioned polymerizable groups and the color filter resin of the present invention are exposed during exposure when the colored layer is formed using the color filter resin composition of the present invention. The alkali-soluble resin and polyfunctional monomer contained in the composition can be easily polymerized, and the pigment dispersant can be stably present in the colored layer of the color filter. When a liquid crystal display device is manufactured using such a color filter, the pigment dispersant can be prevented from bleeding out to the liquid crystal layer or the like.

  In addition, since the organic acid compound contains a polymerizable group, the polymerizable groups of the organic acid compound can be polymerized before being used for forming the colored layer, and as a result, the pigment dispersant has a high molecular weight. Therefore, at the time of development for forming the colored layer, the resin composition for a color filter at an unexposed portion can be made particularly excellent in alkali developability.

  In addition, the organic acid compound represented by the said general formula (III) and general formula (IV) can be used individually by 1 type or in combination of 2 or more types.

<Halogenated hydrocarbon>
The halogenated hydrocarbon used in the present invention is a block copolymer having the above-mentioned repeating unit (1) represented by the general formula (I) and the repeating unit (2) represented by the general formula (II). A salt is formed with the amino group of the repeating unit (1).
In the present invention, by using the above-mentioned halogenated hydrocarbon, the salt-forming site produced by the pigment dispersant is excellent in adsorptivity to the pigment, so that it can exhibit high dispersibility, and at the same time, the dispersant Heat resistance and alkali resistance can be increased.

Examples of the halogenated hydrocarbon include those in which any one of a chlorine atom, a bromine atom and an iodine atom is substituted with a hydrogen atom of a saturated or unsaturated linear, branched or cyclic hydrocarbon. . Among these, a halogenated hydrocarbon in which one of the hydrogen atoms of the hydrocarbon is substituted with a halogen atom is preferable from the viewpoint of forming a salt with the pigment dispersant and improving the pigment dispersibility.
The halogenated hydrocarbon may be linear, branched or cyclic. The number of carbon atoms is preferably 1-18, and more preferably 1-7.

  Among the halogenated hydrocarbons, examples of the halogenated alkyl include those having 1 to 18 carbon atoms, but are not particularly limited. Specifically, for example, methyl chloride, methyl bromide, ethyl chloride, ethyl bromide, methyl iodide, ethyl iodide, n-butyl chloride, hexyl chloride, octyl chloride, dodecyl chloride, tetradecyl chloride, hexadecyl chloride, etc. Can be mentioned. Examples of the allyl halide include allyl chloride, allyl bromide, and allyl iodide. Further, examples of the aralkyl group of the halogenated aralkyl include those having 7 to 18 carbon atoms, but are not particularly limited. Specific examples include benzyl chloride, benzyl bromide, benzyl iodide, naphthylmethyl chloride, pyridylmethyl chloride, naphthylmethyl bromide, pyridylmethyl bromide and the like.

  Among these, at least one selected from the group consisting of benzyl halide, allyl halide, and methyl halide is easy to form a salt, and the formed salt-forming site has excellent adsorptivity to the pigment. This is preferable.

  The content of the organic acid compound and / or halogenated hydrocarbon in the block copolymer used in the present invention is not particularly limited as long as good dispersion stability is exhibited. It is about 0.01-2.0 molar equivalent with respect to the tertiary amino group represented by (I), More preferably, it is 0.1-1.0 molar equivalent. In such a case, the pigment dispersibility and the pigment dispersion stability are excellent. In addition, when using 2 or more types of the said organic acid compound and / or halogenated hydrocarbon together, content which added these should just be in the said range.

<Manufacture of pigment dispersant made of salt type block copolymer>
As a method for producing the block copolymer of the pigment dispersant, the repeating unit (1), the repeating unit (2), the amino group of the repeating unit (1), and the organic The method is not particularly limited as long as it can produce a salt formed with an acid compound and / or a halogenated hydrocarbon. In the present invention, for example, the repeating unit (1) and the repeating unit (2) are polymerized using a known polymerization means, and then dissolved or dispersed in a solvent described later, and then the organic acid is dissolved in the solvent. A pigment dispersant can be produced by adding a compound and / or halogenated hydrocarbon and stirring.

  The polymerization means is not particularly limited as long as it is a means capable of polymerizing the above repeating unit (1) and repeating unit (2) in a desired number to obtain a desired molecular weight, and has a vinyl group. A method generally used for polymerization of a compound can be employed, and for example, anionic polymerization, living radical polymerization, or the like can be used. In the present invention, among them, a method in which polymerization proceeds in a living manner, such as group transfer polymerization (GTP) disclosed in “J. Am. Chem. Soc.” 105, 5706 (1983), is used. preferable. According to this method, the molecular weight, the molecular weight distribution, etc. can be easily set in a desired range, so that the dispersibility of the pigment dispersant can be made uniform.

  In the pigment dispersion for a color filter of the present invention, the content of the pigment dispersant is not particularly limited as long as the pigment can be uniformly dispersed. For example, the total content of the pigment dispersant can be 10 to 150 parts by weight with respect to 100 parts by weight of the pigment. Furthermore, it is preferable to mix | blend in the ratio of 15-45 weight part with respect to 100 weight part of pigments, and it is preferable to mix | blend especially in the ratio of 15-40 weight part. If the content of the pigment dispersant is within the above range, the pigment can be uniformly dispersed.

  In the red pigment dispersion for a color filter of the present invention, the content of the pigment dispersant represented by the general formula (1) may be appropriately adjusted and is not particularly limited. Usually, the content of the pigment dispersant represented by the general formula (1) is preferably in the range of 0.5 to 25 parts by weight, more preferably 1.0 to 20 with respect to 100 parts by weight of the pigment. It is preferably within the range of parts by weight.

Further, in the red pigment dispersion for the color filter of the present invention, the content of the polymer dispersant used preferably in combination with the pigment dispersant represented by the general formula (1) may be appropriately adjusted, There is no particular limitation. In general, the content of the polymer dispersant is preferably in the range of 10 to 150 parts by weight, more preferably in the range of 15 to 40 parts by weight, with respect to 100 parts by weight of the pigment.
In addition, in this invention, the pigment at the time of prescribing | regulating content other than a pigment derivative contains the pigment derivative used at the time of pigment dispersion other than a pigment.

(solvent)
The red pigment dispersion for color filter according to the present invention contains a solvent for dispersing the pigment. The solvent used in the pigment dispersion is not particularly limited as long as it is an organic solvent that does not react with each component in the pigment dispersion and can dissolve or disperse them.
Examples of the solvent used in the pigment dispersion of the present invention include alcohol solvents such as methyl alcohol, ethyl alcohol, N-propyl alcohol, and i-propyl alcohol; cellosolv solvents such as methoxy alcohol and ethoxy alcohol; methoxyethoxyethanol, Carbitol solvents such as ethoxyethoxyethanol; ester solvents such as ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate and ethyl lactate; ketone solvents such as acetone, methyl isobutyl ketone and cyclohexanone; methoxyethyl acetate , Propylene glycol monomethyl ether acetate, 3-methoxy-3-methyl-1-butyl acetate, 3-methoxybutyl acetate, methoxybutyl acetate, ethoxy Cellosolve acetate solvents such as til acetate and ethyl cellosolve acetate; Carbitol acetate solvents such as methoxyethoxyethyl acetate, ethoxyethoxyethyl acetate, and butyl carbitol acetate (BCA); Diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol Ether solvents such as monomethyl ether and tetrahydrofuran; aprotic amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone; lactone solvents such as γ-butyrolactone; benzene, toluene and xylene , Unsaturated hydrocarbon solvents such as naphthalene; saturated hydrocarbons such as N-heptane, N-hexane and N-octane Organic solvents such as system solvents can be mentioned. Among these solvents, cellosolve acetate solvents such as methoxyethyl acetate, propylene glycol monomethyl ether acetate, 3-methoxy-3-methyl-1-butyl acetate, 3-methoxybutyl acetate, ethoxyethyl acetate, ethyl cellosolve acetate; Carbitol acetate solvents such as methoxyethoxyethyl acetate, ethoxyethoxyethyl acetate, butyl carbitol acetate (BCA); ether solvents such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether; methyl methoxypropionate, ethoxypropionic acid Ester solvents such as ethyl and ethyl lactate; ketone solvents such as cyclohexanone are preferred Used. Among them, as the solvent used in the present invention, propylene glycol monomethyl ether acetate (CH ₃ OCH ₂ CH (CH ₃ ) OCOCH ₃ ), propylene glycol monomethyl ether, butyl carbitol acetate (BCA), 3-methoxy-3-methyl- One or more selected from the group consisting of 1-butyl acetate, 3-methoxybutyl acetate and cyclohexanone is preferable from the viewpoints of solubility of other components and coating suitability.

These solvents may be used alone or in combination of two or more.
The pigment dispersion of the present invention is prepared by using the solvent as described above usually at a ratio of 60 to 85% by weight with respect to the total amount of the pigment dispersion containing the solvent. When the amount of the solvent is too small, the viscosity increases and the pigment dispersibility tends to decrease. Moreover, when there are too many solvents, a pigment density | concentration will fall and it may be difficult to achieve the chromaticity coordinate which makes a resin composition the target after preparation.

(Pigment derivative)
As long as the effect of the present invention is not impaired, a pigment derivative may be included. Such a pigment derivative is a compound having a role of imparting a functional group to the pigment skeleton and adding various functions to the pigment. When a pigment derivative is added to the pigment at the time of pigment dispersion, the pigment-like skeleton of the pigment derivative is adsorbed or bonded to the surface of the pigment, whereby the surface of the pigment becomes polar, so that the affinity between the dispersant and the pigment is increased. It is considered that the dispersibility and dispersion stability can be secured.
As the pigment derivative, a phthalimide alkylated derivative of a red or yellow pigment may be used because aggregation of the pigment is suppressed even after the high-temperature heating step in the color filter step.
In the present invention, a sulfonated derivative of a diketopyrrolopyrrole pigment may be included as long as the effect of the present invention is not impaired, but it is not necessary to include it.

(Phthalimide alkylated derivatives of red or yellow pigments)
In the pigment dispersion of the present invention, C.I. I. Phthalimide alkylated derivatives of CI Pigment Red 254 and / or C.I. I. It is preferable to use a phthalimide alkylated derivative of CI Pigment Red 255, since aggregation of the pigment is suppressed even after the high-temperature heating step in the color filter step, and in particular, high contrast can be achieved. In addition, a phthalimide alkylated derivative of a yellow pigment may be used.

Examples of the alkyl group of the phthalimidoalkyl group include linear or branched alkyl groups having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, a propyl group, and a hexyl group. Among these, from the viewpoint of easy production, the alkyl group of the phthalimidoalkyl group is preferably a methyl group.
Further, the substitution number n of the phthalimidoalkyl group is preferably 1 to 2, and is preferably 1 from the viewpoint that both the ease of adsorbing the pigment and the improvement of the heat resistance can be achieved.

As a pigment derivative, it can be used individually by 1 type or in mixture of 2 or more types.
In the present invention, each of the pigment derivatives is C.I. I. It is preferable to contain in the range of 0.5-25 weight part with respect to 100 weight part of pigment containing pigment red 254, and also 1-20 weight part.

(Other ingredients)
If necessary, the pigment dispersion liquid of the present invention may further contain a pigment dispersion auxiliary resin and other components.
Examples of the pigment dispersion auxiliary resin include alkali-soluble resins exemplified by a resin composition described later. In some cases, the steric hindrance of the alkali-soluble resin makes it difficult for the pigment particles to come into contact with each other.
Other components include, for example, surfactants for improving wettability, silane coupling agents for improving adhesion, antifoaming agents, repellency inhibitors, antioxidants, anti-aggregation agents, and UV absorbers. Etc.

<Method for producing pigment dispersion>
The pigment dispersion of the present invention is prepared by the above-described C.C. I. It is preferable to have a step of dispersing a pigment containing CI Pigment Red 254.
In the dispersion process, as a disperser for performing dispersion treatment, a roll mill such as a two-roll or a three-roll, a ball mill such as a ball mill or a vibration ball mill, a paint conditioner, a continuous disk type bead mill, a bead mill such as a continuous annular type bead mill, or the like. Can be mentioned. As a preferable dispersion condition of the bead mill, the bead diameter to be used is preferably 0.03 to 2.00 mm, and more preferably 0.05 to 1.0 mm.

  Specifically, preliminary dispersion is performed with 2 mm zirconia beads having a relatively large bead diameter, and main dispersion is further performed with 0.1 mm zirconia beads having a relatively small bead diameter. Moreover, it is preferable to filter with a membrane filter of 0.5 to 0.1 μm after dispersion.

In the present invention, the dispersion time for dispersion using a known disperser is appropriately adjusted and is not particularly limited. For example, when a paint shaker is used so that the average dispersion particle size of the pigment is about 15 to 70 nm. Is preferably 5 to 50 hours from the viewpoint of realizing high contrast by refining the pigment.
In this way, a pigment dispersion having excellent pigment particle dispersibility is obtained. The pigment dispersion is used as a preliminary preparation for preparing a red resin composition for a color filter having excellent pigment dispersibility.

  As the pigment dispersibility of the pigment dispersion thus obtained, the viscosity at 23 ° C. is preferably 10.0 mPa · s or less, and more preferably 8.0 mPa · s or less. As dispersion stability, the viscosity when left at 23 ° C. for 1 week is also preferably 10.0 mPa · s or less, more preferably 8.0 mPa · s or less. Here, the viscosity at 23 ° C. can be determined by measuring the viscosity at 6 rpm using a rheometer (for example, rheometer MCR-301 manufactured by Anton Paar (cone plate CP50-1)).

2. Red resin composition for color filters The red resin composition for color filters according to the present invention comprises at least the red pigment dispersion for color filters according to the present invention and a curable binder component.

According to the red resin composition for a color filter according to the present invention, C.I. I. By including a pigment dispersion obtained by dispersing CI Pigment Red 254 using the pigment dispersant represented by the general formula (1) according to the present invention, C.I. I. Pigment Red 254 is excellent in dispersion stability and a red colored layer having excellent contrast can be obtained.
Hereinafter, the component used for such a red resin composition for color filters of this invention is demonstrated.
In addition, about the component which may be contained in the red pigment dispersion liquid for color filters which concerns on the said invention, since the thing similar to what was demonstrated in the location of the said pigment dispersion liquid can be used, description here is abbreviate | omitted. .

  The red resin composition for a color filter of the present invention may contain a pigment dispersion other than the red pigment dispersion for a color filter according to the present invention. For example, the red pigment dispersion for a color filter according to the present invention is C.I. I. A pigment dispersion containing only Pigment Red 254 may be used, and a yellow pigment dispersion or another red pigment dispersion may be separately prepared and used in combination. These other pigment dispersions can be similarly prepared using the same components as those described in the red pigment dispersion for color filters according to the present invention.

(Curable binder component)
The resin composition for a color filter according to the present invention contains a curable binder component in order to impart film formability and adhesion to the surface to be coated, and to impart sufficient hardness to the coating film. It does not specifically limit as a curable binder component, The curable binder component used in forming the coloring layer of a conventionally well-known color filter can be used suitably.
Examples of the curable binder component include a curable binder component including a photocurable resin that can be polymerized and cured by visible light, ultraviolet light, electron beam, and the like, and a thermosetting resin that can be polymerized and cured by heating. What contains a thermosetting binder component can be used.

  When the color filter resin composition according to the present invention can be selectively deposited in a pattern on a substrate to form a colored layer, for example, when used in an inkjet method, the developability of the curable binder component is There is no need. In this case, a well-known thermosetting binder component, a photocurable binder component, etc. which are used when forming a color filter colored layer by an inkjet system etc. can be used suitably. For example, a binder property composed of a polyfunctional epoxy compound having two or more epoxy groups in one molecule and a relatively small molecular weight described in JP 2007-003945 A, and a polymer containing an epoxy group in a repeating unit. A thermosetting binder component composed of an epoxy compound and a curing agent such as a polyvalent carboxylic acid anhydride or a polyvalent carboxylic acid is preferably used.

  On the other hand, when using a photolithography process when forming a colored layer, the photosensitive binder component which has alkali developability is used suitably. Examples of the photosensitive binder component include a positive photosensitive binder component and a negative photosensitive binder component. Examples of the positive photosensitive binder component include an alkali-soluble resin and a system containing an o-quinonediazide group-containing compound as a photosensitizing component, and examples of the alkali-soluble resin include a polyimide precursor.

  The negative photosensitive binder component is generally composed of (i) an alkali-soluble resin, (ii) a polyfunctional monomer, (iii) a photopolymerization initiator, a sensitizer, and the like. Hereinafter, these components will be specifically described.

(I) Alkali-soluble resin The alkali-soluble resin in the present invention has a carboxyl group in the side chain, acts as a binder resin, and is preferably soluble in an alkali developer, particularly preferably used in pattern formation. As long as there is, it can be selected and used as appropriate.
A preferable alkali-soluble resin in the present invention is a resin having a carboxyl group, and specific examples thereof include an acrylic copolymer having a carboxyl group and an epoxy (meth) acrylate resin having a carboxyl group. Among these, particularly preferred are those having a carboxyl group in the side chain and further having a photopolymerizable functional group such as an ethylenically unsaturated group in the side chain. This is because the film strength of the cured film formed by containing the photopolymerizable functional group is improved. These acrylic copolymers and epoxy acrylate resins may be used as a mixture of two or more.

The acrylic copolymer having a carboxyl group is obtained by copolymerizing a carboxyl group-containing ethylenically unsaturated monomer and an ethylenically unsaturated monomer.
The acrylic copolymer having a carboxyl group may further contain a structural unit having an aromatic carbocyclic ring. The aromatic carbocycle functions as a component that imparts coating properties to the resin composition.
The acrylic copolymer having a carboxyl group may further contain a structural unit having an ester group. The structural unit having an ester group not only functions as a component that suppresses alkali solubility of the resin composition, but also functions as a component that improves solubility in a solvent and further solvent resolubility.

Examples of the acrylic copolymer having a carboxyl group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec- Butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) Acrylate, n-decyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, disi Lopentanyl (meth) acrylate, 1-adamantyl (meth) acrylate, allyl (meth) acrylate, 2,2′-oxybis (methylene) bis-2-propenoate, styrene, γ-methylstyrene, glycidyl (meth) acrylate, 2- Selected from hydroxylethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, N-vinyl-2-pyrrolidone, N-methylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, etc. One or more, (meth) acrylic acid, dimer of acrylic acid (for example, M-5600 manufactured by Toagosei Chemical Co., Ltd.), itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, anhydrous Copolymer consisting of one or more selected from among objects The can be exemplified. In addition, for example, a polymer having an ethylenically unsaturated bond introduced by adding an ethylenically unsaturated compound having a reactive functional group such as a glycidyl group or a hydroxyl group to the above copolymer can be exemplified, but the present invention is not limited thereto. Is not to be done.
Among these, a polymer having an ethylenically unsaturated bond introduced, for example, by adding an ethylenically unsaturated compound having a glycidyl group or a hydroxyl group to the copolymer is polymerized with a polyfunctional monomer described later at the time of exposure. This is particularly suitable in that the colored layer becomes more stable.

  The copolymerization ratio of the carboxyl group-containing ethylenically unsaturated monomer in the carboxyl group-containing copolymer is usually 5 to 50% by weight, preferably 10 to 40% by weight. In this case, when the copolymerization ratio of the carboxyl group-containing ethylenically unsaturated monomer is less than 5% by weight, the solubility of the resulting coating film in an alkaline developer is lowered, and pattern formation becomes difficult. On the other hand, when the copolymerization ratio exceeds 50% by weight, there is a tendency that the formed pattern is easily detached from the substrate or the pattern surface is roughened during development with an alkali developer.

  The preferred molecular weight of the carboxyl group-containing copolymer is preferably in the range of 1,000 to 500,000, more preferably 3,000 to 200,000. If it is less than 1,000, the binder function after curing is remarkably lowered, and if it exceeds 500,000, pattern formation may be difficult during development with an alkaline developer.

Although it does not specifically limit as an epoxy (meth) acrylate resin which has a carboxyl group, The epoxy (meth) obtained by making the reaction material of an epoxy compound and unsaturated group containing monocarboxylic acid react with an acid anhydride. Acrylate compounds are suitable.
Although it does not specifically limit as an epoxy compound, A bisphenol A type epoxy compound, a bisphenol F type epoxy compound, a bisphenol S type epoxy compound, a phenol novolac type epoxy compound, a cresol novolak type epoxy compound, an aliphatic epoxy compound, or Examples thereof include epoxy compounds such as bisphenolfluorene type epoxy compounds. These may be used alone or in combination of two or more.

  Examples of the unsaturated group-containing monocarboxylic acid include (meth) acrylic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl phthalic acid, (meth) acryloyloxyethyl hexahydrophthalic acid, (Meth) acrylic acid dimer, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid and the like. These unsaturated group-containing monocarboxylic acids may be used alone or in combination of two or more.

Acid anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendo Dibasic acid anhydrides such as methylenetetrahydrophthalic acid, chlorendic anhydride, methyltetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, biphenyl Aromatic polycarboxylic anhydrides such as ether tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, endobicyclo- [2 , 2,1] -Hept-5-ene-2,3-dica Polycarboxylic anhydride derivatives such as carbon anhydride, and the like. These may be used alone or in combination of two or more.
The molecular weight of the epoxy (meth) acrylate compound having a carboxyl group thus obtained is not particularly limited, but is preferably 1000 to 40000, more preferably 2000 to 5000.

(Ii) Polyfunctional monomer Examples of the polyfunctional monomer in the present invention include di (meth) acrylates of alkylene glycol such as ethylene glycol and propylene glycol; di (meth) acrylate of polyalkylene glycol such as polyethylene glycol and polypropylene glycol. ) Acrylates; poly (meth) acrylates of polyhydric alcohols such as glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, etc. and their dicarboxylic acid modified products; polyesters, epoxy resins, urethane resins, alkyd resins , Oligo (meth) acrylates such as silicone resins and spirane resins; both terminal hydroxypoly-1,3-butadiene, both terminal hydroxypolyisoprene, both terminal hydroxypolycaprolactone, etc. Examples thereof include di (meth) acrylates of terminal hydroxylated polymers; tris (2- (meth) acryloyloxyethyl) phosphate and the like.

  Of these polyfunctional monomers, poly (meth) acrylates of polyhydric alcohols having three or more valences and their dicarboxylic acid-modified products are preferable. Specifically, trimethylolpropane tri (meth) acrylate, pentaerythritol tris. Succinic acid modified products of (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like are preferable. The said polyfunctional monomer can be used individually or in mixture of 2 or more types.

  The usage-amount of the polyfunctional monomer in this invention is 5-500 weight part normally with respect to 100 weight part of alkali-soluble resin, Preferably it is 20-300 weight part. If the content of the polyfunctional monomer is less than the above range, the photocuring may not sufficiently proceed and the exposed part may be eluted, and if the content of the polyfunctional monomer is more than the above range, the alkali developability is lowered. there's a possibility that.

(Iii) Photopolymerization initiator and sensitizer The negative photosensitive binder component is usually blended with a photopolymerization initiator having activity with respect to the wavelength of the light source used. The photopolymerization initiator is appropriately selected in consideration of the difference in the reaction format of the polymer having photopolymerization and the photopolymerization monomer (for example, radical polymerization and cationic polymerization) and the kind of each material, and is not particularly limited.

  Examples of photopolymerization initiators are compounds that generate free radicals by the energy of ultraviolet rays, and include biimidazole compounds, benzoin compounds, acetophenone compounds, benzophenone compounds, α-diketone compounds, and polynuclear quinone compounds. , Xanthone compounds, thioxanthone compounds, triazine compounds, ketal compounds, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, thiuram compounds, fluoroamine compounds, oxime ester compounds Compound etc. are mentioned. These can be used alone or in combination.

  The content of the photoinitiator used in the red resin composition for a color filter of the present invention is usually about 0.01 to 100 parts by weight, preferably 5 to 60 parts by weight with respect to 100 parts by weight of the polyfunctional monomer. It is. If the content is less than the above range, the polymerization reaction cannot be sufficiently caused, so that the colored layer may not have sufficient hardness. There may be a case where the content of the pigment or the like in the solid content of the composition is relatively reduced, and a sufficient coloring density cannot be obtained.

  Moreover, in this invention, 1 or more types chosen from the group of a sensitizer and a hardening accelerator can also be further used together with the said photoinitiator as needed. Specific examples of the sensitizer include 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 4-diethylaminoacetophenone, 4-dimethylaminopropiophenone, ethyl-4- Dimethylaminobenzoate, 2-ethylhexyl-1,4-dimethylaminobenzoate, 2,5-bis (4-diethylaminobenzal) cyclohexanone, 7-diethylamino-3- (4-diethylaminobenzoyl) coumarin, 4- (diethylamino) chalcone Etc. Specific examples of the curing accelerator include 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2,5-dimercapto-1,3,4-thiadiazole, 2-mercapto-4, Examples include chain transfer agents such as 6-dimethylaminopyridine, 1-phenyl-5-mercapto-1H-tetrazole, and 3-mercapto-4-methyl-4H-1,2,4-triazole.

(Optional additive)
The red resin composition for a color filter of the present invention may contain various additives as necessary within the range where the object of the present invention is not impaired. Examples of the additive include a polymerization terminator, a chain transfer agent, a leveling agent, a plasticizer, a surfactant, an antifoaming agent, a silane coupling agent, an ultraviolet absorber, and an adhesion promoter.
Among these, surfactants that can be used include, for example, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene Examples include glycol dilaurate, polyethylene glycol distearate, sorbitan fatty acid esters, fatty acid-modified polyesters, and tertiary amine-modified polyurethanes. In addition, a fluorosurfactant can also be used.
Furthermore, examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, and tricresyl. Examples of the antifoaming agent and leveling agent include silicon-based, fluorine-based, and acrylic compounds.

<Combination ratio of each component in the resin composition>
The total pigment content is preferably 4 to 50% by weight, more preferably 10 to 50% by weight, and even more preferably 15 to 40% by weight based on the total solid content of the resin composition. If the amount of the pigment is too small, the transmission density when the resin composition is applied to a predetermined film thickness (usually 1.0 to 4.0 μm) may be insufficient. If the amount of the pigment is too large, the resin composition may be reduced. There are fears that coating properties such as adhesion to the substrate when coated and cured on the substrate, surface roughness of the cured film, and coating film hardness may be insufficient, and pigments in the resin composition Since the ratio of the amount of the dispersant used for dispersion increases, characteristics such as developability and heat resistance may be insufficient. In addition, in this invention, solid content is all things other than the solvent mentioned above, and the polyfunctional monomer etc. which are melt | dissolving in the solvent are also contained.
In addition, the total content of the pigment dispersant is preferably in the range of 1 to 50% by weight, and more preferably in the range of 5 to 35% by weight, based on the total solid content of the resin composition. Is preferred. If the content is less than 1% by weight relative to the total solid content of the resin composition, it may be difficult to uniformly disperse the pigment, and if it exceeds 50% by weight, curing may occur. There is a risk of deteriorating the processability and developability.
The total amount of the curable binder component is preferably 15 to 95% by weight, preferably 25 to 80% by weight, based on the total solid content of the resin composition.
Further, the content of the solvent is not particularly limited as long as the colored layer can be accurately formed. Usually, it is preferably in the range of 65 to 95% by weight, particularly preferably in the range of 75 to 88% by weight, based on the total amount of the resin composition containing the solvent. When the content of the solvent is within the above range, the coating property can be excellent.

(Manufacture of red resin composition for color filters)
As a method for producing the resin composition of the present invention, the pigment dispersion according to the present invention, another pigment dispersion, a photosensitive binder component, and if necessary, a solvent and various additional components are added and mixed. A method can be mentioned.
As the pigment dispersion, the red pigment dispersion according to the present invention and, if necessary, further another pigment dispersion may be prepared as separate pigment dispersions and mixed at the time of preparing the resin composition.
The red resin composition for a color filter of the present invention is preferable in that a pigment dispersion is produced and used in advance, so that aggregation of the pigment can be effectively prevented and dispersed uniformly.

Next, the color filter of the present invention will be described.
[Color filter]
The color filter of the present invention is a color filter comprising at least a transparent substrate and a colored layer provided on the transparent substrate, wherein at least one of the colored layers is the above-described red resin composition for a color filter of the present invention. It has the coloring layer formed by hardening | curing. By using the resin composition of the present invention, the color filter of the present invention can be provided with a high contrast red colored layer without lowering the luminance.
Such a color filter of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the color filter of the present invention. According to FIG. 1, the color filter 10 of the present invention has a transparent substrate 1, a light shielding part 2, and a colored layer 3.

(Colored layer)
The colored layer used in the color filter of the present invention is not particularly limited as long as it is formed by curing the above-described red resin composition for a color filter of the present invention, but is usually on a transparent substrate described later. Depending on the type of pigment formed in the opening of the light-shielding part and contained in the red resin composition for color filters, it is composed of three or more colored patterns.
In addition, the arrangement of the colored layers is not particularly limited, and for example, a general arrangement such as a stripe type, a mosaic type, a triangle type, or a four-pixel arrangement type can be used. Moreover, the width | variety, area, etc. of a colored layer can be set arbitrarily.
Although the thickness of the said colored layer is suitably controlled by adjusting the coating method, the solid content concentration of a resin composition for color filters, a viscosity, etc., it is preferable that it is normally the range of 1-5 micrometers.

The colored layer can be formed, for example, by the following method.
First, the above-described red resin composition for a color filter of the present invention is applied onto a transparent substrate to be described later using an application means such as a spray coating method, a dip coating method, a bar coating method, a coal coating method, or a spin coating method. To form a wet paint film.
Next, after drying the wet coating film using a hot plate or oven, it is exposed to light through a mask having a predetermined pattern, and an alkali-soluble resin and a polyfunctional monomer are photopolymerized. And a coating film of a red resin composition for a color filter. Examples of the light source used for exposure include ultraviolet rays such as a low-pressure mercury lamp, a high-pressure mercury lamp, and a metal halide lamp, and an electron beam. The exposure amount is appropriately adjusted depending on the light source used, the thickness of the coating film, and the like.
Moreover, in order to promote a polymerization reaction after exposure, you may heat-process. The heating conditions are appropriately selected depending on the blending ratio of each component in the red resin composition for color filter to be used, the thickness of the coating film, and the like.

Next, it develops using a developing solution, a coating film is formed with a desired pattern by melt | dissolving and removing an unexposed part. As the developer, a solution in which an alkali is dissolved in water or a water-soluble solvent is usually used. An appropriate amount of a surfactant or the like may be added to the alkaline solution. Further, a general method can be adopted as the developing method.
After the development treatment, the developer is usually washed and the cured coating film of the resin composition is dried to form a colored layer. In addition, you may heat-process in order to fully harden a coating film after image development processing. The heating conditions are not particularly limited and are appropriately selected depending on the application of the coating film.

(Shading part)
The light shielding part in the color filter of the present invention is formed in a pattern on a transparent substrate described later, and can be the same as that used as a light shielding part in a general color filter.
The pattern shape of the light shielding portion is not particularly limited, and examples thereof include a stripe shape and a matrix shape. Examples of the light-shielding portion include those obtained by dispersing or dissolving a black pigment in a binder resin, and metal thin films such as chromium and chromium oxide. The metal thin film may be a CrO _x film (x is an arbitrary number) and a laminate of two Cr films, and a CrO _x film (x is an arbitrary number) with a reduced reflectance. , CrN _y film (y is an arbitrary number) and three layers of Cr film may be laminated.
When the light-shielding part is a material in which a black colorant is dispersed or dissolved in a binder resin, the light-shielding part can be formed by any method that can pattern the light-shielding part, and is not particularly limited. For example, a photolithography method, a printing method, an ink jet method and the like using the resin composition for the light shielding part can be exemplified.

  In the above case, when a printing method or an inkjet method is used as a method for forming the light shielding portion, examples of the binder resin include polymethyl methacrylate resin, polyacrylate resin, polycarbonate resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, hydroxy Examples thereof include ethyl cellulose resin, carboxymethyl cellulose resin, polyvinyl chloride resin, melamine resin, phenol resin, alkyd resin, epoxy resin, polyurethane resin, polyester resin, maleic acid resin, polyamide resin and the like.

  In the above case, when a photolithography method is used as a method for forming the light shielding portion, the binder resin may be, for example, an acrylate-based, methacrylate-based, polyvinyl cinnamate-based, or cyclized rubber-based reactive material. A photosensitive resin having a vinyl group is used. In this case, a photopolymerization initiator may be added to the resin composition for a light shielding part containing a black pigment such as carbon black or titanium black as a pigment and a photosensitive resin, and further a sensitizer if necessary. Application improvers, development improvers, crosslinking agents, polymerization inhibitors, plasticizers, flame retardants, and the like may be added.

  On the other hand, when the light shielding part is a metal thin film, the method for forming the light shielding part is not particularly limited as long as the light shielding part can be patterned, and for example, photolithography, vapor deposition using a mask. Method, printing method and the like.

  The thickness of the light shielding part is set to about 0.2 to 0.4 μm in the case of a metal thin film, and about 0.5 to 2 μm in the case where a black colorant is dispersed or dissolved in a binder resin. Is set.

(Transparent substrate)
The transparent substrate in the color filter of the present invention is not particularly limited as long as it is a base material transparent to visible light, and a transparent substrate used for a general color filter can be used. Specific examples include inflexible transparent rigid materials such as quartz glass, alkali-free glass, and synthetic quartz plates, or transparent flexible materials having flexibility such as transparent resin films and optical resin plates. It is done.
Although the thickness of the said transparent substrate is not specifically limited, According to the use of the color filter of this invention, the thing of about 100 micrometers-1 mm can be used, for example.
The color filter of the present invention may be one in which, for example, an overcoat layer, a transparent electrode layer, an alignment film, a columnar spacer, or the like is formed in addition to the transparent substrate, the light shielding portion, and the colored layer. .

Next, the liquid crystal display device of the present invention will be described.
[Liquid Crystal Display]
The liquid crystal display device of the present invention includes the color filter of the present invention described above, a counter substrate, and a liquid crystal layer formed between the color filter and the counter substrate.
Such a liquid crystal display device of the present invention will be described with reference to the drawings. FIG. 2 is a schematic view showing an example of the liquid crystal display device of the present invention. As illustrated in FIG. 2, the liquid crystal display device 40 of the present invention includes a color filter 10, a counter substrate 20 having a TFT array substrate and the like, and a liquid crystal layer formed between the color filter 10 and the counter substrate 20. 30.
Note that the liquid crystal display device of the present invention is not limited to the configuration shown in FIG. 2, but can be a configuration generally known as a liquid crystal display device using a color filter.

The driving method of the liquid crystal display device of the present invention is not particularly limited, and a driving method generally used for a liquid crystal display device can be employed. Examples of such a drive method include a TN method, an IPS method, an OCB method, and an MVA method. In the present invention, any of these methods can be preferably used.
Further, the counter substrate can be appropriately selected and used according to the driving method of the liquid crystal display device of the present invention.
Furthermore, as the liquid crystal constituting the liquid crystal layer, various liquid crystals having different dielectric anisotropy and mixtures thereof can be used according to the driving method of the liquid crystal display device of the present invention.

As a method for forming the liquid crystal layer, a method generally used as a method for manufacturing a liquid crystal cell can be used, and examples thereof include a vacuum injection method and a liquid crystal dropping method.
In the vacuum injection method, for example, a liquid crystal cell is prepared in advance using a color filter and a counter substrate, and the liquid crystal is heated to obtain an isotropic liquid, and the liquid crystal is applied to the liquid crystal cell using the capillary effect. The liquid crystal layer can be formed by injecting in this state and sealing with an adhesive. Thereafter, the sealed liquid crystal can be aligned by slowly cooling the liquid crystal cell to room temperature.
In the liquid crystal dropping method, for example, a sealant is applied to the periphery of the color filter, the color filter is heated to a temperature at which the liquid crystal becomes isotropic, and the liquid crystal is dropped in an isotropic liquid state using a dispenser or the like. In addition, the liquid crystal layer can be formed by overlapping the color filter and the counter substrate under reduced pressure and bonding them with a sealant. Thereafter, the sealed liquid crystal can be aligned by slowly cooling the liquid crystal cell to room temperature.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
(Synthesis Example 1) Pigment dispersant 1
47.2 parts by weight of nitrobenzene was stirred while the temperature was raised to 120 ° C., and 2.77 parts by weight of cyanuric chloride and 3.35 parts by weight of 1-aminoanthraquinone were added. Subsequently, it stirred at 120 degreeC for 2 hours. 2.06 parts by weight of p-aminobenzoic acid was added. Subsequently, it stirred at 135-140 degreeC for 2 hours. 5.20 parts by weight of p-aminobenzenesulfonic acid and 2.07 parts by weight of potassium carbonate were added. Subsequently, it stirred at 180 degreeC for 6 hours. After cooling to room temperature, it was washed 3 times with 300 ml of water. The wet cake was vacuum dried at 80 ° C. to obtain a yellow product. The molecular weight of the target product having the following structure was confirmed by TOF-MS (manufactured by BRUKER, REFLEX II).

(Synthesis example 2) Pigment dispersant 2
Synthesis was carried out by changing the p-aminobenzoic acid of Synthesis Example 1 to m-aminobenzoic acid and p-aminobenzenesulfonic acid to m-aminobenzenesulfonic acid, and having the following structure by TOF-MS as described above. The molecular weight of the target product was confirmed.

(Synthesis example 3) Pigment dispersant 3
47.2 parts by weight of nitrobenzene was stirred while the temperature was raised to 120 ° C., and 2.77 parts by weight of cyanuric chloride and 3.35 parts by weight of 1-aminoanthraquinone were added. Subsequently, it stirred at 120 degreeC for 2 hours. Aniline 1.40 parts by weight were added. Subsequently, it stirred at 135-140 degreeC for 2 hours. 4.11 parts by weight of m-aminobenzoic acid and 2.07 parts by weight of potassium carbonate were added. Subsequently, it stirred at 180 degreeC for 6 hours. After cooling to room temperature, it was washed 3 times with 300 ml of water. The wet cake vacuum dried at 80 ° C. is added to 83.75 parts by weight of 10% fuming sulfuric acid. Subsequently, it stirred at 30 degreeC for 6.5 hours. The reaction solution was added to 250 parts by weight of ice water and stirred, and then the precipitate was filtered. The obtained wet cake was washed three times with 150 parts by weight of water. The wet cake was vacuum dried at 80 ° C. to obtain a yellow product. Similarly to the above, the molecular weight of the target product having the following structure was confirmed by TOF-MS.

(Comparative Synthesis Example 1) Comparative pigment dispersant 1
While increasing the temperature of 31.4 parts by weight of nitrobenzene to 170 ° C., 1.84 parts by weight of cyanuric chloride and 4.46 parts by weight of 1-aminoanthraquinone were added. Subsequently, it stirred at 170 degreeC for 5 hours. 2.14 parts by weight of o-methylaniline was added. Subsequently, it stirred at 180 degreeC for 5 hours. After cooling to room temperature, it was washed 3 times with 200 ml of water. The wet cake vacuum dried at 80 ° C. is added to 210 parts by weight of 5% fuming sulfuric acid. Subsequently, it stirred at 30 degreeC for 5 hours. The reaction solution was added to 250 parts by weight of ice water and stirred, and then the precipitate was filtered. The obtained wet cake was washed three times with 200 parts by weight of water. The wet cake was vacuum dried at 80 ° C. to obtain a yellow product. Similarly to the above, the molecular weight of the target product having the following structure was confirmed by TOF-MS.

(Comparative Synthesis Example 2) Comparative pigment dispersant 2
Synthesis was performed by changing the p-aminobenzoic acid of Synthesis Example 1 to aniline, and the molecular weight of the target product having the following structure was confirmed by TOF-MS in the same manner as described above.

(Comparative Synthesis Example 3) Comparative pigment dispersant 3
Synthesis was performed by changing m-aminobenzoic acid in Synthesis Example 3 to p-aminobenzenesulfonic acid, and the molecular weight of the target product having the following structure was confirmed by TOF-MS in the same manner as described above.

(Comparative Synthesis Example 4) Comparative pigment dispersant 4
300.0 parts by weight of 20% fuming sulfuric acid was stirred while being cooled to 10 ° C., and 30.0 parts by weight of Pigment Red 254 was added. Subsequently, it stirred at 63 degreeC for 6 hours.
The reaction solution was added to 3000 parts by weight of ice water and stirred for 15 minutes, and then the precipitate was filtered. The obtained wet cake was washed with 2000 ml of water and filtered. Vacuum drying at 80 ° C. gave a red product. Similarly to the above, the molecular weight of the target product having the following structure (n = 1) was confirmed by TOF-MS.

(Production Example 1 Preparation of Dispersant Solution a)
In a 100 mL round bottom flask, 20.1 parts by weight of propylene glycol monomethyl ether acetate (PGMEA) was added to a polymer dispersant (repeating unit (1) represented by the above general formula (I) and the above general formula (II) A block copolymer having a repeating unit (2) represented by: Trade name: BYK-LPN6919, manufactured by Big Chemie) (weight average molecular weight 7800, amine number 130, solid content 60% by weight) 1.45 parts by weight, Dispersant solution a which is a block copolymer type polymer dispersant partially formed by adding 0.1 part by weight of phenylphosphonic acid (trade name: PPA, manufactured by Nissan Chemical Co., Ltd.) and treating with ultrasonic waves for 15 minutes It was.
At this time, the amino group of the block copolymer (BYK-LPN6919) is salt-formed by an acid / base reaction with the phosphonic acid group of PPA.

Example 1
(1) Preparation of Red Pigment Dispersion for Color Filter Fine pigment (CI Pigment Red 254 (PR254: average primary particle size 15-50 nm) 3.705 parts by weight, Pigment Dispersant 1 is 0 as a pigment dispersant 21.6 parts by weight of the dispersant solution a prepared in Production Example 1 and an alkali-soluble resin (styrene / benzyl methacrylate / acrylic acid / 2-hydroxymethyl acrylate copolymer (molar ratio 30/40 / 10/20, acid value: 70 mg KOH / g, molecular weight 6000, solid content 44.1% by weight, diluted with propylene glycol monomethyl ether acetate) Red pigment dispersion with 1% pigment concentration and 13% pigment dispersion for 10 hours with 0.1 mm zirconia beads Was obtained. Note that the packing ratio of the beads in the vessel during dispersion was 50%.

(Evaluation: Dispersibility / Dispersion stability)
The viscosity of the prepared pigment dispersion was measured at 6 rpm with an Anton Paar rheometer MCR-301 (cone plate CP50-1, measured at 23 ° C.). The viscosity over time was measured again after the dispersion was stored at room temperature (23 ° C.) for 1 week. When either viscosity exceeded 10 mPa · s, the dispersion stability was evaluated as x. The results are shown in Table 1.

(2) Preparation of red resin composition for color filter To 4.06 parts by weight of the red pigment dispersion A obtained above, 2.22 parts by weight of the following binder composition, 3.72 parts by weight of propylene glycol monomethyl ether acetate, interface Activating agent R08MH (manufactured by DIC) 0.01 parts by weight and silane coupling agent KBM503 (manufactured by Shin-Etsu Silicone) 0.05 parts by weight are added and mixed, and pressure filtration is performed to obtain a red resin composition for a color filter of Example 1. I got a thing.

<Binder composition>
Alkali-soluble resin (styrene / benzyl methacrylate / acrylic acid / 2-hydroxymethyl acrylate copolymer (molar ratio 30/40/10/20, acid value: 70 mg KOH / g, molecular weight 6000)): 11.0 parts by weight Tetrafunctional acrylate monomer (trade name: Aronix M450, manufactured by Toagosei Co., Ltd.): 8.2 parts by weight / photopolymerization initiator (2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropane -1-one (trade name: Irgacure 907, manufactured by Ciba Specialty Chemicals Co., Ltd.): 1.0 part by weight-photopolymerization initiator (2-benzyl-2-dimethylamino-1- (4-morpholino) Phenyl) -1-butanone (trade name Irgacure 369, manufactured by Ciba Specialty Chemicals): 2.4 parts by weight / photosensitization (4,4'-bis (dimethylamino) benzophenone): 0.7 parts by weight Solvent (propylene glycol monomethyl ether acetate): 43.2 parts by weight

(Evaluation: Contrast)
The obtained red resin composition for a color filter was applied on a glass substrate having a thickness of 0.7 mm (“NA35” manufactured by NH Techno Glass Co., Ltd.) using a spin coater. Then, it heat-dried for 3 minutes on an 80 degreeC hotplate. A photocured film (red colored layer) was obtained by exposure (60 mJ) using a small aligner. The cured film was heated in an oven at 230 ° C. for 30 minutes to obtain a cured film after post-baking.
Luminance was measured using a contrast measurement device CT-1 manufactured by Aisaka Electric Co., Ltd., light source: F10 lamp between cold cathodes, and luminance meter: LS-100 manufactured by Konica Minolta. The contrast can be derived from the following formula using the measured luminance value.
Contrast = parallel luminance (cd / m ² ) / orthogonal luminance (cd / m ² )
The results are shown in Table 1.

(Examples 2-3)
In Example 1, pigment dispersions and resin compositions of Examples 2 to 3 were obtained in the same manner as in Example 1 except that the pigment dispersant 1 was changed to pigment dispersants 2 and 3, respectively. Moreover, it carried out similarly to Example 1, and produced the cured film after the post-baking of Examples 2-3.
The pigment dispersion and dispersion stability of the pigment dispersion and the contrast of the post-baked cured film were evaluated. The results are shown in Table 1.

(Comparative Example 1)
In Example 1, as the pigment dispersant, the triazine skeleton-containing pigment dispersant (Pigment Dispersant 1) is not used, but only the dispersant solution a and the alkali-soluble resin are used, and the refined pigment (C.I. Pigment Red 254 ( PR254: average primary particle size 15 to 50 nm) Except for 3.9 parts by weight, a pigment dispersion and a resin composition of Comparative Example 1 were obtained in the same manner as in Example 1. Also, in the same manner as in Example 1. Thus, a cured film after post-baking of Comparative Example 1 was produced.
The pigment dispersion and dispersion stability of the pigment dispersion and the contrast of the post-baked cured film were evaluated. The results are shown in Table 1.

(Comparative Examples 2 to 5)
In Example 1, pigment dispersions and resin compositions of Comparative Examples 2 to 5 were obtained in the same manner as in Example 1 except that the pigment dispersant 1 was changed to the comparative pigment dispersants 1 to 4, respectively. Moreover, it carried out similarly to Example 1, and produced the cured film after the post-baking of Comparative Examples 2-5.
The pigment dispersion and dispersion stability of the pigment dispersion and the contrast of the post-baked cured film were evaluated. The results are shown in Table 1.

In Examples 1-3 using the pigment dispersants 1-3 according to the present invention, C.I. I. It was revealed that a red colored layer having excellent dispersion stability and excellent contrast of Pigment Red 254 was obtained.
On the other hand, in Comparative Example 1 in which the triazine skeleton-containing pigment dispersant was not used, the pigment dispersibility and the pigment dispersion stability were poor, and the contrast of the resulting red colored layer was also poor.
Further, in Comparative Example 2 using the pigment dispersant having a dianthraquinone triazine skeleton, the pigment dispersibility and the pigment dispersion stability were poor, and the contrast of the obtained red colored layer was also inferior.
Furthermore, in Comparative Examples 3 and 4 using a pigment dispersant having a monoanthraquinone triazine skeleton and having one or two sulfonic acid groups, the pigment dispersion stability is poor, and the contrast of the resulting red colored layer is also low. It became inferior.
Further, in Comparative Example 5 using a pigment dispersant having a diketopyrrolopyrrole skeleton and having one sulfonic acid group, although the pigment dispersion stability was good, the luminance was lowered and the resulting red coloration was obtained. The contrast of the layer was also inferior.

DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Light-shielding part 3 Colored layer 10 Color filter 20 Opposite substrate 30 Liquid crystal layer 40 Liquid crystal display device

Claims (9)

A pigment dispersant represented by the following general formula (1).

(In Formula (1), n is an integer of 1-16, m is an integer of 1-16.)   A pigment dispersion containing a pigment, a pigment dispersant, and a solvent, wherein the pigment is C.I. I. A red pigment dispersion for a color filter, comprising Pigment Red 254, wherein the pigment dispersant includes a pigment dispersant represented by the general formula (1) according to claim 1.   The red pigment dispersion for a color filter according to claim 2, wherein the pigment dispersant further comprises a polymer dispersant which is a block copolymer containing a tertiary amine salt or a quaternary ammonium salt. liquid. The polymer dispersant has a repeating unit (1) represented by the following general formula (I) and a repeating unit (2) represented by the following general formula (II), and further includes the repeating unit (1 4. The red pigment dispersion for a color filter according to claim 3, comprising a polymer dispersant that is a block copolymer in which at least a part of the amino group of the organic acid compound and the organic acid compound form a salt.

[In Formula (I) and Formula (II), R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and A is a carbon atom having 1 carbon atom. To 8 alkylene groups, — [CH (R ⁶ ) —CH (R ⁷ ) —O] _x —CH (R ⁶ ) —CH (R ⁷ ) — or — [(CH ₂ ) _y —O] _z — ( CH _{2) y} - ₂ monovalent group represented by, ^{R 4} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl ^{group, - [CH (R 6)} -CH It is a monovalent group represented by (R ⁷ ) —O] _x —R ⁸ or — [(CH ₂ ) _y —O] _z —R ⁸ . R ⁶ and R ⁷ are each independently a hydrogen atom or a methyl group, and R ⁸ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, It is a monovalent group represented by —CHO, —CH ₂ CHO, or —CH ₂ COOR ⁹ , and R ⁹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The alkyl group, alkenyl group, aralkyl group, and aryl group each may have a substituent.
x is an integer of 1 to 18, y is an integer of 1 to 5, and z is an integer of 1 to 18. m represents an integer of 3 to 200, and n represents an integer of 10 to 200. ]   The blending ratio of the pigment dispersant represented by the general formula (1) is 0.5 to 25 parts by weight with respect to 100 parts by weight of the pigment, according to any one of claims 2 to 4. The red pigment dispersion for the color filter described. The organic acid compound in the polymer dispersant is at least one selected from the group consisting of organic acids represented by the following general formula (III) and the following general formula (IV). The red pigment dispersion for the color filter described.

[In Formula (III) and Formula (IV), R ^a and R ^{a ′} are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, or an aryl group. 1 represented by the group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e , or —O—R ^{a ″.} the valence of the group, one of R ^a and R ^{a 'comprises} a carbon atom. R ^{a ″} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e. ,-[(CH ₂ ) _t —O] _u —R ^e .
R ^b is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , — [(CH ₂ ) _t —O] _u —R ^e or a monovalent group represented by —O—R ^{b ′} . R ^{b ′} is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, — [CH (R ^c ) —CH (R ^d ) —O] _s —R ^e , or _- it is a monovalent group represented by _{[(CH 2) t -O]} u -R e.
R ^c and R ^d are each independently a hydrogen atom or a methyl group, and R ^e is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aralkyl group, an aryl group, _{-CHO, -CH 2 CHO, -CO-} CH = CH 2, a monovalent group represented by _{-CO-C (CH 3) =} CH 2 or _-CH 2 COOR ^{f, R f} is hydrogen or C It is an alkyl group of formula 1-5.
In R ^a , R ^{a ′} , and R ^b , each of the alkyl group, alkenyl group, aralkyl group, and aryl group may have a substituent.
s is an integer of 1 to 18, t is an integer of 1 to 5, and u is an integer of 1 to 18. ]   A red resin composition for a color filter, comprising at least the red pigment dispersion for a color filter according to any one of claims 1 to 6 and a curable binder component.   A color filter comprising a colored layer formed by curing the red resin composition for a color filter according to claim 7.   9. A liquid crystal display device comprising: the color filter according to claim 8; a counter substrate; and a liquid crystal layer formed between the color filter and the counter substrate.

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