JP6869575B2 - Pigment fine particles, pigment dispersions, photosensitive coloring compositions and color filters - Google Patents

Description

The present invention relates to novel pigment fine particles, a pigment dispersion using the same, a photosensitive coloring composition, and a color filter.

Color filters used in liquid crystal display devices and solid-state image sensors generally apply a coloring composition in which a resin or the like is mixed with a liquid obtained by dissolving or dispersing a color material of a dye or pigment in a solvent on a glass substrate, a silicon substrate, or the like. After that, it is manufactured through processes such as exposure / curing, development, and heat curing. Since the durability of a color filter is related to the life of a liquid crystal display device and a solid-state image sensor, a pigment dispersion method using a pigment having excellent heat resistance and solvent resistance as a coloring material of a coloring composition has become the mainstream. The pigment dispersion used here is mainly a non-aqueous pigment dispersion in which the pigment is dispersed in an organic solvent, and the primary particle size, dispersion particle size, crystallinity, etc. of the pigment fine particles contained in the dispersion are used. The characteristics greatly affect the performance such as the color characteristics of the final product, the color filter.

In recent years, color filters used in liquid crystal display devices and solid-state image sensors are required to have high definition and low power consumption. In order to achieve these, the color characteristics of the color filter are strongly required to have higher contrast, higher brightness, and higher coloring power.

As the organic pigment used for the colorant for the red filter segment, it is common to use an organic pigment having excellent light resistance and heat resistance such as diketopyrrolopyrrole pigment, anthraquinone pigment or disazo pigment alone or in combination. However, since these commercially available organic pigments have a large primary particle size and are non-uniform, it is impossible to achieve the color characteristics required for a color filter even if they are used as they are.
Therefore, many studies have been made to miniaturize these organic pigments.

In particular, diketopyrrolopyrrole pigments have been favorably used in recent years as organic pigments having excellent brightness, and among them, C.I. I. Pigment Red 254 and brominated diketopyrrolopyrrole are being actively studied for miniaturization (hereinafter, also referred to as "micronization") as they are organic pigments having particularly excellent color characteristics.

For example, so-called salt milling in which an inorganic salt such as sodium chloride as described in Patent Documents 1 and 2 is used as a medium, an organic pigment and an organic solvent are premixed and treated with a kneader to pulverize the organic pigment. Pigment fine particles by mixing a solution in which an organic pigment as described in the method, Patent Document 3, Patent Document 4 or Patent Document 5 is dissolved in a good solvent and a poor solvent of an organic pigment compatible with the good solvent. A so-called reprecipitation method, or a method for refining an organic pigment, which is a combination of a reprecipitation method and a salt milling method as described in Patent Document 6, has been proposed.

Further, as described in Patent Document 7, a thin film fluid formed between at least two processing surfaces arranged so as to face each other, which can be approached and separated from each other, and at least one of which rotates relative to the other. Provided is a method for producing fine particles in which a pigment solution in which an organic pigment is dissolved and a precipitation solvent for precipitating organic pigment fine particles are mixed.

Japanese Unexamined Patent Publication No. 2012-21970 Japanese Unexamined Patent Publication No. 2014-177532 Japanese Unexamined Patent Publication No. 2011-046846 Japanese Unexamined Patent Publication No. 2011-137142 International Publication WO2011 / 024896 Pamphlet Japanese Unexamined Patent Publication No. 2015-102858 International Publication WO2011 / 096401 Pamphlet

By using the organic pigment fine particles that have been miniaturized by applying these conventional techniques, there may be a certain effect on the color filter performance such as high contrast and high brightness. However, according to the studies by the present inventors, none of these obtained by the conventional techniques has sufficiently satisfied the high contrast and high brightness required for the color filter, and Patent Document 3 And Patent Document 5 and the like add substances other than coloring materials, so that organic pigment fine particles and dispersions thereof can be obtained, which can obtain a color filter having high contrast and high coloring power, which has been strongly demanded in recent years. Not.

The problem to be solved by the present invention is high contrast and high brightness diketopyrrolopyrrole pigment fine particles, and when a pigment dispersion containing the pigment fine particles is used, a good filter segment is formed. It is an object of the present invention to provide a photosensitive coloring composition having required performance and an excellent balance of the performance, and a high-definition color filter using the same and excellent in contrast and brightness.

As a result of diligent research by the inventors, it was confirmed that the diketopyrrolopyrrole pigment mainly grows crystals in three directions, and in particular, the crystallite size in a specific crystal growth direction is below a certain value. A diketopyrrolopyrrole pigment having a specific crystallite size ratio within a certain range with respect to each crystal growth direction has a fine and uniform primary particle size, and is required when used as a color filter. It was found that the characteristics of the above were satisfied at a high level in a well-balanced manner.

[上記一般式（I）において、Ｘ_１及びＸ_２は、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]
（２）Ｘ線回折パターンにより算出される結晶格子面のうち（±１ ±１ ±１）の８個の面の中でＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズが１４０Å以下であり、Ｘ線回折パターンにより算出される（１ ５ −１）面方向の結晶子サイズが８０Å以下であり、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（３）Ｘ線回折パターンにより算出される（±１ ±１ ±１）の８個の結晶格子面面のうちＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズを、Ｘ線回折パターンにより算出される結晶格子面のうち、２θ＝３〜１０°における最大ピークに対応する面方向の結晶子サイズで除して算出される結晶子サイズの比が、０．８５〜１．２５であり、かつ平均一次粒子径が５〜４０ｎｍであることを特徴とする、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（４）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズが１４０Å以下であり、一般式（I）で示される化合物を９０％以上含有するジケトピロロピロール系顔料微粒子。
（５）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズが１４０Å以下であり、Ｘ線回折パターンにより算出される２θ＝２８．０°±０．３°に対応する結晶格子面の結晶子サイズが８０Å以下であることを特徴とする、一般式（I）で示される化合物を９０％以上含有するジケトピロロピロール系顔料微粒子。
（６）平均一次粒子径が５〜４０ｎｍである上記（１）、（２）、（４）又は（５）に記載のジケトピロロピロール系顔料微粒子。
（７）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズを、Ｘ線回折パターンにより算出される２θ＝７．４°±０．３°に対応する結晶格子面の結晶子サイズで除して算出される結晶子サイズの比が０．８５〜１．２５であり、かつ平均一次粒子径が５〜４０ｎｍであることを特徴とする、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（８）Ｘ線回折パターンにより算出される２θ＝３〜１０°における最大ピークに対応する結晶格子面の面間隔の、８０℃における値と２３０℃における値の変化率（下記特定式による）が３．０％以下であることを特徴とする上記（１）〜（７）のいずれかに記載のジケトピロロピロール系顔料微粒子。
８０℃における値と２３０℃における値の変化率＝
｛（２３０℃における面間隔）/（８０℃における面間隔）×１００｝−１００（％）［特定式］
（９）Ｘ線回折パターンにより算出される２θ＝７．４°±０．３°に対応する結晶格子面の面間隔の、８０℃における値と２３０℃における値の変化率（下記特定式による）が３．０％以下であることを特徴とする上記（１）〜（７）のいずれかに記載のジケトピロロピロール系顔料微粒子。
８０℃における値と２３０℃における値の変化率＝
｛（２３０℃における面間隔）/（８０℃における面間隔）×１００｝−１００（％）［特定式］ The present invention has been solved by the following means.
(1) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine crystals containing 90% or more of the compound represented by the following general formula (I).

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ]
(2) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine particles containing the compound represented by the general formula (I), which has the following, the crystallite size in the (15-1) plane direction calculated by the X-ray diffraction pattern is 80 Å or less.
(3) X-ray diffraction determines the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern among the eight crystal lattice planes (± 1 ± 1 ± 1) calculated by the X-ray diffraction pattern. Of the crystal lattice planes calculated by the pattern, the ratio of the crystallite size calculated by dividing by the crystallite size in the plane direction corresponding to the maximum peak at 2θ = 3 to 1.25 ° is 0.85 to 1.25. A diketopyrrolopyrrole pigment fine crystal containing a compound represented by the general formula (I), which is characterized by having an average primary particle size of 5 to 40 nm.
(4) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and 90% of the compounds represented by the general formula (I) are used. Diketopyrrolopyrrole pigment fine particles contained above.
(5) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and 2θ = 28. Diketopyrrolopyrrole pigment fine particles containing 90% or more of the compound represented by the general formula (I), characterized in that the crystallite size of the crystal lattice plane corresponding to 0 ° ± 0.3 ° is 80 Å or less. ..
(6) The diketopyrrolopyrrole pigment fine particles according to (1), (2), (4) or (5) above, wherein the average primary particle size is 5 to 40 nm.
(7) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 2θ = 7.4 ° ± 0 calculated by the X-ray diffraction pattern. It is characterized in that the ratio of the crystallite size calculated by dividing by the crystallite size of the crystal lattice plane corresponding to 3 ° is 0.85 to 1.25, and the average primary particle size is 5 to 40 nm. Diketopyrrolopyrrole-based pigment fine crystals containing the compound represented by the general formula (I).
(8) The rate of change between the value at 80 ° C and the value at 230 ° C (according to the following specific formula) of the interplanar spacing of the crystal lattice plane corresponding to the maximum peak at 2θ = 3 to 10 ° calculated by the X-ray diffraction pattern. The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (7) above, wherein the content is 3.0% or less.
Rate of change between the value at 80 ° C and the value at 230 ° C =
{(Surface spacing at 230 ° C) / (Surface spacing at 80 ° C) x 100} -100 (%) [Specific formula]
(9) Rate of change between the value at 80 ° C and the value at 230 ° C of the interplanar spacing of the crystal lattice plane corresponding to 2θ = 7.4 ° ± 0.3 ° calculated by the X-ray diffraction pattern (according to the following specific formula). ) Is 3.0% or less, the diketopyrrolopyrrole pigment fine particles according to any one of (1) to (7) above.
Rate of change between the value at 80 ° C and the value at 230 ° C =
{(Surface spacing at 230 ° C) / (Surface spacing at 80 ° C) x 100} -100 (%) [Specific formula]

[上記一般式（II）において、Ｒが、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]
（１４）Ｒが臭素である下記式（III）で示されることを特徴とする上記（１３）記載のジケトピロロピロール系顔料微粒子。

（１５）Ｘ線回折パターンにより算出される結晶格子面のうち（±１ ±１ ±１）の８個の面の中でＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズが１４０Å以下であり、式（III）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（１６）有機顔料と有機溶媒とを少なくとも含有する顔料分散体であって、該有機顔料が、上記（１）〜（１５）のいずれかに記載のジケトピロロピロール系顔料微粒子であることを特徴とする顔料分散体。
（１７）上記（１）〜（１５）のいずれかに記載の顔料微粒子を少なくとも含有する感光性着色組成物。
（１８）上記（１７）に記載の感光性着色組成物を少なくとも含有するカラーフィルター。
（１９）上記（１）〜（１５）のいずれかに記載の顔料微粒子を少なくとも含有するカラーフィルター。 (10) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (9) above, wherein the standard deviation of the primary particle size is less than 7.0.
(11) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (10), wherein the coefficient of variation (CV value) of the primary particle size is less than 30.
(12) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (11) above, wherein the Fe content is 35 ppm or less.
(13) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (12) above, wherein the general formula (I) is represented by the following general formula (II).

[In the above general formula (II), R may have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent independently of each other. Indicates an alkyl group or an aryl group which may have a substituent. ]
(14) The diketopyrrolopyrrole pigment fine particles according to (13) above, wherein R is bromine and is represented by the following formula (III).

(15) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine crystals containing the compound represented by the formula (III) below.
(16) A pigment dispersion containing at least an organic pigment and an organic solvent, wherein the organic pigment is the diketopyrrolopyrrole pigment fine particles according to any one of (1) to (15) above. A characteristic pigment dispersion.
(17) A photosensitive coloring composition containing at least the pigment fine particles according to any one of (1) to (15) above.
(18) A color filter containing at least the photosensitive coloring composition according to (17) above.
(19) A color filter containing at least the pigment fine particles according to any one of (1) to (15) above.

According to the present invention, a diketopyrrolopyrrole pigment fine particle having any of the characteristics (1) to (15) described above, a pigment dispersion containing the pigment fine particle, a photosensitive coloring composition and a color filter are provided. Can be provided. By using the pigment fine particles, it is possible to easily disperse the pigment fine particles, and when a pigment dispersion containing the pigment fine particles is used, it is used as a color filter with high contrast, high coloring power, and excellent heat resistance. It has become possible to provide a photosensitive coloring composition having very suitable performance and a color filter having excellent contrast and brightness using the photosensitive coloring composition.

It is a schematic sectional drawing of the fluid processing apparatus used for carrying out the fluid processing method which concerns on embodiment of this invention. (A) is a schematic plan view of the first processing surface of the fluid processing apparatus shown in FIG. 1, and (B) is an enlarged view of a main part of the processing surface of the apparatus. (A) is a cross-sectional view of a second introduction part of the apparatus, and (B) is an enlarged view of a main part of a processing surface for explaining the second introduction part. Brominated diketopyrrolopyrrole and C.I. I. It is an X-ray diffraction pattern figure of Pigment Red 254. Brominated diketopyrrolopyrrole and C.I. I. It is a schematic view which saw the zigzag in the laminated structure of the cedar twill pattern which the surface of the aromatic ring in the crystal of Pigment Red 254 was zigzag from diagonally above. Brominated diketopyrrolopyrrole and C.I. I. It is a schematic diagram which looked at the zigzag from the side in the laminated structure of the cedar twill pattern in which the surface of the aromatic ring in the crystal of Pigment Red 254 was zigzag. It is a schematic diagram which shows the relationship of a secondary particle, a primary particle, a crystal face, and a crystal plane.

Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not construed as being limited thereto.

[上記一般式（I）において、Ｘ_１及びＸ_２は、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]
（２）Ｘ線回折パターンにより算出される結晶格子面のうち（±１ ±１ ±１）の８個の面の中でＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズが１４０Å以下であり、Ｘ線回折パターンにより算出される（１ ５ −１）面方向の結晶子サイズが８０Å以下であり、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（３）Ｘ線回折パターンにより算出される（±１ ±１ ±１）の８個の結晶格子面面のうちＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズを、Ｘ線回折パターンにより算出される結晶格子面のうち、２θ＝３〜１０°における最大ピークに対応する面方向の結晶子サイズで除して算出される結晶子サイズの比が、０．８５〜１．２５であり、かつ平均一次粒子径が５〜４０ｎｍであることを特徴とする、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（４）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズが１４０Å以下であり、一般式（I）で示される化合物を９０％以上含有するジケトピロロピロール系顔料微粒子。
（５）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズが１４０Å以下であり、Ｘ線回折パターンにより算出される２θ＝２８．０°±０．３°に対応する結晶格子面の結晶子サイズが８０Å以下であることを特徴とする、一般式（I）で示される化合物を９０％以上含有するジケトピロロピロール系顔料微粒子。
（６）平均一次粒子径が５〜４０ｎｍである上記（１）、（２）、（４）又は（５）に記載のジケトピロロピロール系顔料微粒子。
（７）Ｘ線回折パターンにより算出される２θ＝２４．５°±０．３°に対応する結晶格子面の結晶子サイズを、Ｘ線回折パターンにより算出される２θ＝７．４°±０．３°に対応する結晶格子面の結晶子サイズで除して算出される結晶子サイズの比が０．８５〜１．２５であり、かつ平均一次粒子径が５〜４０ｎｍであることを特徴とする、一般式（I）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（８）Ｘ線回折パターンにより算出される２θ＝３〜１０°における最大ピークに対応する結晶格子面の面間隔の、８０℃における値と２３０℃における値の変化率（下記特定式による）が３．０％以下であることを特徴とする上記（１）〜（７）のいずれかに記載のジケトピロロピロール系顔料微粒子。
８０℃における値と２３０℃における値の変化率＝
｛（２３０℃における面間隔）/（８０℃における面間隔）×１００｝−１００（％）［特定式］
（９）Ｘ線回折パターンにより算出される２θ＝７．４°±０．３°に対応する結晶格子面の面間隔の、８０℃における値と２３０℃における値の変化率（下記特定式による）が３．０％以下であることを特徴とする上記（１）〜（７）のいずれかに記載のジケトピロロピロール系顔料微粒子。
８０℃における値と２３０℃における値の変化率＝
｛（２３０℃における面間隔）/（８０℃における面間隔）×１００｝−１００（％）［特定式］
（１０）一次粒子径の標準偏差が７．０未満であることを特徴とする上記（１）〜（９）のいずれかに記載のジケトピロロピロール系顔料微粒子。
（１１）一次粒子径の変動係数（ＣＶ値）が３０未満であることを特徴とする（１）〜（１０）のいずれかに記載のジケトピロロピロール系顔料微粒子。
（１２）Ｆｅの含有量が３５ｐｐｍ以下であることを特徴とする上記（１）〜（１１）のいずれかにに記載のジケトピロロピロール系顔料微粒子。
（１３）上記一般式（I）が、下記一般式（II）で示されることを特徴とする上記（１）〜（１２）のいずれかに記載のジケトピロロピロール系顔料微粒子。

[上記一般式（II）において、Ｒが、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]
（１４）Ｒが臭素である下記式（III）で示されることを特徴とする上記（１３）記載のジケトピロロピロール系顔料微粒子。

（１５）Ｘ線回折パターンにより算出される結晶格子面のうち（±１ ±１ ±１）の８個の面の中でＸ線回折パターンにおける最大ピークに対応する面方向の結晶子サイズが１４０Å以下であり、式（III）で示される化合物を含有するジケトピロロピロール系顔料微粒子。
（１６）有機顔料と有機溶媒とを少なくとも含有する顔料分散体であって、該有機顔料が、上記（１）〜（１５）のいずれかに記載のジケトピロロピロール系顔料微粒子であることを特徴とする顔料分散体。
（１７）上記（１）〜（１５）のいずれかに記載の顔料微粒子を少なくとも含有する感光性着色組成物。
（１８）上記（１７）に記載の感光性着色組成物を少なくとも含有するカラーフィルター。
（１９）上記（１）〜（１５）のいずれかに記載の顔料微粒子を少なくとも含有するカラーフィルター。 The diketopyrrolopyrrole pigment fine particles in the present invention have any of the following characteristics (1) to (15).
(1) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine crystals containing 90% or more of the compound represented by the following general formula (I).

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ]
(2) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine particles containing the compound represented by the general formula (I), which has the following, the crystallite size in the (15-1) plane direction calculated by the X-ray diffraction pattern is 80 Å or less.
(3) X-ray diffraction determines the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern among the eight crystal lattice planes (± 1 ± 1 ± 1) calculated by the X-ray diffraction pattern. Of the crystal lattice planes calculated by the pattern, the ratio of the crystallite size calculated by dividing by the crystallite size in the plane direction corresponding to the maximum peak at 2θ = 3 to 1.25 ° is 0.85 to 1.25. A diketopyrrolopyrrole pigment fine crystal containing a compound represented by the general formula (I), which is characterized by having an average primary particle size of 5 to 40 nm.
(4) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and 90% of the compounds represented by the general formula (I) are used. Diketopyrrolopyrrole pigment fine particles contained above.
(5) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and 2θ = 28. Diketopyrrolopyrrole pigment fine particles containing 90% or more of the compound represented by the general formula (I), characterized in that the crystallite size of the crystal lattice plane corresponding to 0 ° ± 0.3 ° is 80 Å or less. ..
(6) The diketopyrrolopyrrole pigment fine particles according to (1), (2), (4) or (5) above, wherein the average primary particle size is 5 to 40 nm.
(7) The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 2θ = 7.4 ° ± 0 calculated by the X-ray diffraction pattern. It is characterized in that the ratio of the crystallite size calculated by dividing by the crystallite size of the crystal lattice plane corresponding to 3 ° is 0.85 to 1.25, and the average primary particle size is 5 to 40 nm. Diketopyrrolopyrrole-based pigment fine crystals containing the compound represented by the general formula (I).
(8) The rate of change between the value at 80 ° C and the value at 230 ° C (according to the following specific formula) of the interplanar spacing of the crystal lattice plane corresponding to the maximum peak at 2θ = 3 to 10 ° calculated by the X-ray diffraction pattern. The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (7) above, wherein the content is 3.0% or less.
Rate of change between the value at 80 ° C and the value at 230 ° C =
{(Surface spacing at 230 ° C) / (Surface spacing at 80 ° C) x 100} -100 (%) [Specific formula]
(9) Rate of change between the value at 80 ° C and the value at 230 ° C of the interplanar spacing of the crystal lattice plane corresponding to 2θ = 7.4 ° ± 0.3 ° calculated by the X-ray diffraction pattern (according to the following specific formula). ) Is 3.0% or less, the diketopyrrolopyrrole pigment fine particles according to any one of (1) to (7) above.
Rate of change between the value at 80 ° C and the value at 230 ° C =
{(Surface spacing at 230 ° C) / (Surface spacing at 80 ° C) x 100} -100 (%) [Specific formula]
(10) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (9) above, wherein the standard deviation of the primary particle size is less than 7.0.
(11) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (10), wherein the coefficient of variation (CV value) of the primary particle size is less than 30.
(12) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (11) above, wherein the Fe content is 35 ppm or less.
(13) The diketopyrrolopyrrole pigment fine particles according to any one of (1) to (12) above, wherein the general formula (I) is represented by the following general formula (II).

[In the above general formula (II), R may have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent independently of each other. Indicates an alkyl group or an aryl group which may have a substituent. ]
(14) The diketopyrrolopyrrole pigment fine particles according to (13) above, wherein R is bromine and is represented by the following formula (III).

(15) Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å. Diketopyrrolopyrrole pigment fine crystals containing the compound represented by the formula (III) below.
(16) A pigment dispersion containing at least an organic pigment and an organic solvent, wherein the organic pigment is the diketopyrrolopyrrole pigment fine particles according to any one of (1) to (15) above. A characteristic pigment dispersion.
(17) A photosensitive coloring composition containing at least the pigment fine particles according to any one of (1) to (15) above.
(18) A color filter containing at least the photosensitive coloring composition according to (17) above.
(19) A color filter containing at least the pigment fine particles according to any one of (1) to (15) above.

According to the present invention, a photosensitive coloring composition using diketopyrrolopyrrole pigment fine particles having any of the characteristics (1) to (15) shown above, particularly a pigment dispersion containing these pigment fine particles, can be obtained. Since the color filter produced from the photosensitive coloring composition obtained by using the above has high contrast, high coloring power, and excellent heat resistance, a photosensitive coloring composition and a color filter having very suitable performance are provided. It became possible to do.

[Pigment type]
The pigment fine particles according to the present invention are pigment fine particles whose pigment type contains a diketopyrrolopyrrole pigment compound represented by the following general formula (I).

[上記一般式（I）において、Ｘ_１及びＸ_２は、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ]

Examples of such diketopyrrolopyrrole pigment compounds include those obtained by various conventionally known production methods and various commercially available products.
For example, USP 4,415,685 and USP 4,579,949 which disclose a method for synthesizing a succinic acid ester using a nitrile compound as a starting material as a basic method for producing a diketopyrrolopyrrole pigment compound. By selecting the type, number, and position of the functional group of the starting material by the method described in these corresponding patents, the type, number, and position of X ₁ and X ₂ of the above general formula (I) can be selected. Can be done.
Further, various improved methods, for example, Japanese Patent Application Laid-Open No. 58-210084, Japanese Patent Application Laid-Open No. 07-90189, Japanese Patent Application Laid-Open No. 08-48908, WO2009 / 81930 Pamphlet, EP1411092 B1 Publication, Japanese Patent Application Laid-Open No. 2012- Those obtained by the method described in Japanese Patent Publication No. 21970 and the like can also be mentioned.
For those equipped with a color index (CI), C.I. I. Pigment Red 254, C.I. I. Pigment Red 255, C.I. I. Pigment Red 264, C.I. I. Pigment Orange 71, C.I. I. Pigment Orange 73 and the like, and various commercial products are also available.

Among these various diketopyrrolopyrrole pigment compounds represented by the general formula (I), the diketopyrrolopyrrole pigment compound represented by the following general formula (II), which has a substituent at the para position, has a color tone. Is excellent and is suitable for use as a red pigment.

[上記一般式（II）において、Ｒが、それぞれ独立に、水素原子、フッ素原子、塩素原子、臭素原子、ヨウ素原子、シアノ基、−ＣＦ_３、置換基を有してもよい飽和もしくは不飽和のアルキル基、または置換基を有してもよいアリール基を示す。]

[In the above general formula (II), R may have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent independently of each other. Indicates an alkyl group or an aryl group which may have a substituent. ]

Among them, C.I., in which R is a chlorine atom. I. Pigment Red 254 or brominated diketopyrrolopyrrole in which R is a bromine atom (formula (III) below) has excellent light resistance, chemical resistance, high saturation, high brightness, and optical properties. It is also suitable for color filter applications, and is particularly preferable.

C. I. Pigment Red 254 and diketopyrrolopyrrole brominated have different spectroscopic hues because of the different types of substituents. Brominated diketopyrrolopyrrole is C.I. I. Compared with Pigment Red 254, the spectral wavelength is shifted to the longer wavelength side, resulting in a more bluish red. These may be appropriately selected and used according to the desired chromaticity.

In particular, the brominated diketopyrrolopyrrole represented by the above formula (III) has an intermolecular bond due to steric hindrance of the bromine atom. I. Since it is weaker than Pigment Red 254, it is easy to make fine particles, and it is possible to obtain performance suitable for a color filter such as high contrast and high brightness, which is more preferable for color filter applications.
In addition, the present inventors have found that the highest contrast can be obtained particularly when the crystallite size and the ratio of crystallite size of the present invention described below are calculated using brominated diketopyrrolopyrrole. ..

The pigment fine particles according to the present invention may contain an organic pigment other than the diketopyrrolopyrrole pigment compound whose pigment type is represented by the general formula (I). By including other organic pigments in this way, the particle size can be controlled and the chromaticity can be adjusted. The organic pigments that can be mixed and used at this time are not particularly limited, and for example, perylene pigments, perinone pigments, quinacridone pigments, quinacridone quinone pigments, anthraquinone pigments, antoanthron pigments, benzimidazolone pigments, etc. Disazo condensation pigments, disazo pigments, azo pigments, indantron pigments, phthalocyanine pigments, triarylcarbonium pigments, dioxazine pigments, aminoanthraquinone pigments, thioindigo pigments, isoindolin pigments, isoindolinone Examples thereof include based pigments, pyranthron facial pigments, isobiolantron based pigments, or compositions and mixtures thereof. The crude pigment can also be used as the organic pigment.

[Crystal size]
1. 1. 1st Embodiment of the present invention In the 1st embodiment of the present invention, the pigment fine particles according to the present invention are 8 of (± 1 ± 1 ± 1) of the crystal lattice planes calculated by the X-ray diffraction pattern. 90% of the compounds represented by the above-mentioned general formula (I) have a crystallite size of 140 Å or less in the plane (hereinafter referred to as “plane α”) direction corresponding to the maximum peak in the X-ray diffraction pattern. It is characterized by containing the above.

The crystallite size in the plane α direction is 140 Å or less, preferably 130 Å or less, more preferably 120 Å or less, and most preferably 100 Å or less.
The content of the compound represented by the general formula (I) is more preferably 90% or more, 95% or more, further preferably 97% or more, and most preferably 99% or more.

When the pigment type contains the compound represented by the general formula (II) described above, the plane α is the plane (1 1 1) shown in FIG. 5, and corresponds to 2θ = 24.5 ° ± 0.3 °. To do. Therefore, when the pigment type contains the compound represented by the above-mentioned general formula (II), the crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° is 140 Å or less. Is preferable.

2. Second Form of the Present Invention In the second form of the present invention, the pigment fine particles according to the present invention have a crystallite size of 140 Å or less in the plane α direction and are calculated by an X-ray diffraction pattern (15). -1) It is characterized by containing a compound represented by the above-mentioned general formula (I) having a crystallite size in the plane (hereinafter referred to as “plane β”) direction of 80 Å or less.

The crystallite size in the plane α direction is 140 Å or less, preferably 130 Å or less, more preferably 120 Å or less, and most preferably 100 Å or less. The crystallite size in the plane β direction is preferably 80 Å or less, more preferably 75 Å or less, still more preferably 70 Å or less.
More preferably, the crystallite size in the plane α direction is 140 Å or less and the crystallite size in the plane β direction is 80 Å or less, and more preferably the crystallite size in the plane α direction is 130 Å or less and the crystallite size in the plane β direction is 75 Å or less. Particularly preferably, the crystallite size in the plane α direction is 120 Å or less and the crystallite size in the plane β direction is 70 Å or less. Most preferably, the crystallite size in the plane α direction is 100 Å or less and the crystallite size in the plane β direction is 70 Å or less.

When the compound represented by the above general formula (II) is contained as the pigment type, the plane α is the (1 1 1) plane as described above, and corresponds to 2θ = 24.5 ° ± 0.3 °. The plane β is the (15-1) plane shown in FIG. 6, and corresponds to 2θ = 28.0 ° ± 0.3 °. Therefore, when the compound represented by the above general formula (II) is contained as the pigment type, the crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° is 140 Å or less, and It is preferable that the crystallite size of the crystal lattice plane corresponding to 2θ = 28.0 ° ± 0.3 ° is 80 Å or less.

3. 3. Third Form of the Present Invention In the third aspect of the present invention, the pigment fine particles according to the present invention have a crystallite size in the plane α direction, and 2θ = The ratio of the crystallite size calculated by dividing by the crystallite size in the plane (hereinafter referred to as “plane γ”) direction corresponding to the maximum peak at 3 to 10 ° is 0.85 to 1.25, and It is characterized by containing the compound represented by the above-mentioned general formula (I), which has an average primary particle size of 5 to 40 nm.

The crystallite size ratio described above is preferably 0.85 to 1.25, more preferably 0.99 to 1.20, and most preferably 0.95 to 1.15.
The average primary particle size is preferably 5 to 40 nm, more preferably 10 to 30 nm, and most preferably 15 to 25 nm.
Further, it is preferable that the crystallite size ratio is 0.85 to 1.25 and the average primary particle size is 5 to 40 nm, and further, the crystallite size ratio is 0.99 to 1.20 and the average primary particle size is 0.99 to 1.20. Those having a crystallite size ratio of 10 to 30 nm are more preferable, and those having a crystallite size ratio of 0.95 to 1.15 and an average primary particle size of 15 to 25 nm are most preferable.

When the compound represented by the above general formula (II) is contained as the pigment type, the plane α is the (1 1 1) plane as described above, and corresponds to 2θ = 24.5 ° ± 0.3 °. .. The plane γ is the (020) plane shown in FIGS. 5 and 6, and corresponds to 2θ = 7.4 ° ± 0.3 °. Therefore, in this case, in the pigment fine particles according to the present invention, the crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is calculated by the X-ray diffraction pattern. The ratio of the crystallite size calculated by dividing by the crystallite size of the crystal lattice plane corresponding to 2θ = 7.4 ° ± 0.3 ° is 0.85 to 1.25, and the average primary particle size. Is preferably 5 to 40 nm.

In particular, the pigment type is C.I. I. In the case of Pigment Red 254, the crystallite size ratio is 0.85 to 1.25, more preferably 0.99 to 1.15, and even more preferably 0.95 to 1.10. The average primary particle size is preferably 5 to 40 nm, more preferably 10 to 30 nm, and most preferably 15 to 25 nm.
Further, the crystallite size ratio is preferably 0.85 to 1.25 and the average primary particle size is 5 to 40 nm, the crystallite size ratio is 0.99 to 1.15 and the average primary particle size is 10. It is more preferably ~ 30 nm, and most preferably the crystallite size ratio is 0.95 to 1.10 and the average primary particle size is 15 to 25 nm.

When the pigment type is brominated diketopyrrolopyrrole, the crystallite size ratio is preferably 0.85 to 1.25, more preferably 0.90 to 1.20, and 0.95 to 1.15. Is the most preferable. The average primary particle size is preferably 5 to 40 nm, more preferably 10 to 30 nm, and most preferably 15 to 25 nm.
Further, the crystallite size ratio is preferably 0.85 to 1.25 and the average primary particle size is 5 to 40 nm, the crystallite size ratio is 0.99 to 1.20, and the average primary particle size is 10. It is more preferably ~ 30 nm, and most preferably the crystallite size ratio is 0.95 to 1.15 and the average primary particle size is 15 to 25 nm.

Table 1 shows the three lattice planes of the compound represented by the general formula (II), that is, the (0 2 0) plane, the (1 1 1) plane, the (1 5-1) plane, and the Bragg angle (2 θ). The relationship is shown.

4. Fourth Form of the Present Invention In the fourth form of the present invention, the pigment fine particles according to the present invention have a crystallite size of 140 Å or less in the plane α direction and are a compound represented by the above-mentioned formula (III). It is characterized by containing brominated diketopyrrolopyrrole).

The ratio of the crystallite size in the preferred plane α direction to the crystallite size in the preferred plane β direction, the ratio of the preferred crystallite size and the primary particle size are the same as those in the second and third forms of the present invention.
The content of the compound represented by the preferred formula (III) is the same as the content of the compound represented by the general formula (I) in the first embodiment of the present invention.

3. 3. Effect of crystallite size and its ratio on performance 3-1 Crystalline size Generally, light is easily scattered at the interface (grain boundary) between the crystallites constituting the primary particles, and the crystal grain boundary is light. It is known to be the main cause of scattering. Therefore, in order to improve the optical properties of the pigment fine particles, it is conceivable to reduce the area of the crystal grain boundaries in the fine particles to reduce the influence of the crystal grain boundaries. Therefore, attempts to reduce grain boundaries have been made in various fields. In order to reduce the area of grain boundaries, it is better that the crystallite size is large. However, as a result of the studies by the present inventors, it has been surprisingly found that the pigment fine particles according to the present invention having a smaller crystallite size as described above have excellent optical properties. Although the mechanism for exhibiting excellent optical characteristics due to the crystallite size of the pigment fine particles according to the present invention is not completely clear, it is presumed as follows.

When the crystallite size is small, the number of interfaces (grain boundaries) between the crystallites constituting the primary particle is large, but the area of each crystal grain boundary is small. Generally, it is considered that light scattering is likely to occur when the area of grain boundaries is large. On the other hand, in the present invention, it is presumed that the area of the crystal grain boundary is reduced, the light scattering is reduced, and the contrast and brightness of the obtained color filter are improved by controlling the crystallite size to be small. Will be done. Here, the small crystallite size means that the crystallite size in the plane α direction is 140 Å or less, and the crystallite size in the plane β direction is 80 Å or less.

Further, as shown in FIG. 7, since the primary particles of the pigment are composed of crystallites, the primary particles can also be reduced by reducing the crystallite size. It is considered that the small primary particles also have high transmittance of the color filter, suppress light scattering low, and improve contrast and brightness. Here, the fact that the primary particles of the pigment are small means that the average primary particle diameter is 40 nm or less.

Further, in the case of a crystal having anisotropy such as the diketopyrrolopyrrole pigment compound represented by the general formula (I), birefringence due to the crystal itself, not the grain boundary, cannot be completely prevented.
In particular, in the case of a diketopyrrolopyrrole pigment compound having a substituent at the para position (general formula (II) described above), the compound has a cedar twill pattern structure, the space group is P21 / n, and has a substituent at the meta position. And tert-butyl-diketopyrrolopyrrole have a brick structure of a pseudo-brick wall and the space group is P1 (with a bar (-) on P1), but the symmetry is low and the anisotropy is high. Therefore, by setting the crystallite size of the surface α to 140 Å or less and the crystallite size of the surface β to 80 Å or less, the isotropic property is further enhanced and excellent optical characteristics are obtained. Obtainable. A bar (-) is attached above P1 as shown in the following number 1.

Further, since the pigment fine particles according to the present invention have small primary particles, it is possible to suppress problems such as foreign matter generation due to the coarse primary particles.

On the other hand, when the crystallite size is large, the primary particles are inevitably also large. As the crystallite size increases, the primary particles also increase, which may hinder the improvement of the contrast and brightness of the color filter.

When the crystallite size exceeds the upper limit of the range of the present invention, for example, 140 Å for the crystallite size in the plane α direction and 80 Å for the crystallite size in the plane β direction, the contrast and brightness of the obtained color filter are obtained. Is not enough. In addition, foreign matter is likely to be generated by coarse particles.
The lower limit of the crystallite size is not particularly limited, but if it is too small, the primary particles will also be smaller than necessary and the specific surface area of the primary particles will increase. As the specific surface area of the primary particles increases, the surface energy of the particles increases, making it difficult to disperse the pigment fine particles in the dispersion medium. Specifically, there is a high possibility that the pigment fine particles will aggregate at the time of dispersion, the viscosity of the pigment dispersion in which the pigment fine particles are dispersed in the dispersion medium is high, and thickening or gelation will occur due to aging. When a larger amount of dispersant is contained in the pigment dispersion in order to stabilize the dispersion, the color component contained in the obtained color filter is reduced, and the dispersant component unnecessary for the color filter characteristics is increased. There is a high possibility that the characteristics will deteriorate and the processability of the color filter will be defective. Further, it has been found by the present inventors that it is technically difficult to make the crystallite size too small, and on the other hand, sufficient performance improvement can be obtained without making it so small. Therefore, it is sufficient to reduce the crystallite size to the above upper limit or less.

3-2 By setting the ratio of the crystallite size to the average primary particle diameter plane α and the crystallite size ratio of the plane γ within the range of the present invention, for example, 0.85 to 1.25, high contrast and high contrast are achieved. It is possible to obtain a bright color filter. Although the mechanism by which the ratio of crystallite size affects the optical characteristics of the color filter is not completely clear, it is presumed as follows.

The fact that the above-mentioned crystallite size ratio, that is, the aspect ratio (hereinafter, also referred to as “crystallite size aspect ratio”) is small means that the crystallites are close to spherical. If it is close to a sphere, the crystallites are densely packed when forming the primary particles, and the crystallites are easily arranged with less anisotropy in the primary particles. It is considered that the reduction of anisotropy in the primary particles makes the primary particles optically uniform, leading to improvement in contrast and brightness. Further, since the crystallites are close to a spherical shape, it is considered that the primary particles formed by the aggregated crystallites are also spherical and have a small aspect ratio. Since the primary particles are close to spherical, the pigment fine particles are less likely to be oriented in the cured film containing the pigment fine particles which are aggregates of the primary particles, and the anisotropy of the cured film is reduced, leading to improvement in contrast and brightness. it is conceivable that.

Further, by setting the ratio of the crystallite sizes described above within the range of the present invention, the pigment dispersion in which the pigment fine particles are dispersed in the dispersion medium can also reduce the amount of the dispersant added and have a low viscosity. The dispersibility can be good. Probably because the aspect ratio of the primary particles is small, the specific surface area of the pigment fine particles formed from the primary particles is small, and the pigment fine particles having a small particle surface energy can be obtained, and it is presumed that the aggregation of the particles is suppressed. To.

When the aspect ratio of the crystallite size exceeds the range of the present invention, the contrast and brightness of the obtained color filter are not sufficient.
In particular, each crystal lattice plane for which the ratio of the crystallite size to the crystallite size is specified in the present invention is the (± 1 ± 1 ± 1) plane (plane α) and 2θ = 3 to 10 calculated by the X-ray diffraction pattern. The planes (planes γ) corresponding to the maximum peak at ° have been clarified by the studies of the present inventors that these planes are useful as indicators of isotropic properties, which is epoch-making. It can be said that it is a thing.

However, even if the aspect ratio of the crystallite is small, if the average primary particle size is large, the contrast and brightness of the obtained color filter will be low. Further, when the average primary particle size is 5 nm or less, even if the ratio of crystallite size is within the above range, the specific surface area of the primary particles becomes large and it becomes easy to aggregate, so that a good dispersion can be obtained. It gets harder. Therefore, the contrast is high only when the pigment fine particles having a crystallite size ratio within the above range and a primary particle size within the above range, for example, an average primary particle size in the range of 5 to 40 nm are used. A high-brightness color filter can be obtained.

[Measurement of crystallite size]
As described above, the crystallite size can be measured by making the Bragg angle (2θ) of the X-ray diffraction spectrum correspond to the lattice plane of the crystal structure.
In the diketopyrrolopyrrole pigment, C.I. I. The crystal structure of Pigment Red 254 has been analyzed by X-ray crystallography in the literature (Acta. Crystal. B49, 1056 (1993)), and the pigment type is C.I. I. In the case of Pigment Red 254, it can be used to measure crystallite size. The X-ray diffraction pattern of brominated diketopyrrolopyrrole is as shown in FIG. I. Although the X-ray diffraction intensity is different from that of Pigment Red 254, the peak position appears at the same location, so that the brominated diketopyrrolopyrrole is C.I. I. The analysis can be performed on the assumption that the crystal structure similar to Pigment Red 254 and the lattice plane of the crystal structure are taken.
Similarly, in the case of other diketopyrrolopyrrole pigments, the crystal structure is analyzed by the X-ray diffraction pattern, and the Bragg angle (2θ) of the X-ray diffraction spectrum is made to correspond to the lattice plane of the crystal structure.

In the present invention, the measurement of the crystallite size of each crystal lattice plane described above is based on the following conditions and procedures.
(1) Powder X-ray diffraction measurement using CuKα ray of a sample is performed in a Bragg angle (2θ) of 5.3 ° to 60 °.
(2) From the X-ray diffraction pattern obtained in (1), a diffraction pattern with the background removed is obtained. The background is removed by connecting the bragg angles (2θ) of the above measurement pattern near 5.3 °, around 6.5 °, around 10 °, and around 60 ° with straight lines to form the background. The operation is to obtain a pattern obtained by removing the value of the X-ray diffraction intensity represented by the ground from the value of the X-ray diffraction intensity obtained in (1).
(3) From the X-ray diffraction pattern obtained in (2) with the background removed, in the compound represented by the general formula (II), the Bragg angle, which is a characteristic diffraction peak of the (020) plane. Diffraction peak near (2θ) = 7.4 ° ± 0.3 ° and Bragg angle (2θ) = 24.5 ° ± 0.3 °, which is a characteristic diffraction peak of the (1 11) plane. Bragg angle (2θ) of half-value width and diffraction peak for each of the diffraction peaks near the peak and the Bragg angle (2θ) = 28.0 ° ± 0.3 °, which is the characteristic diffraction peak of the (15-1) plane. ). The full width at half maximum can be calculated by separating each of the three diffraction peaks existing in the measurement range using commercially available data analysis software. For example, in the examples described later, PANalytical data analysis software HighScorePlus Ver. Using 3.0e (3.0.5), the value of the half width calculated by fitting the peak shape as the Pseudo Voigt function was used.
(4) The crystallite size is calculated by the diffraction peak full width at half maximum calculated in (3) and the Scherrer's formula below.
D = Kλ / (B × cosA)
B = Bobs-b
here,
D: Crystallite size (Å)
Bobs: Half width (rad) calculated in (3)
b: X-ray diffractometer angle resolution correction coefficient, which is the full width at half maximum (rad) at the time of standard silicon crystal measurement. The standard silicon crystal is measured under the following device configuration and measurement conditions, and b = 0.087.
A: Diffraction peak Bragg angle 2θ (rad)
K: Scheller constant (defined as K = 0.90)
λ: X-ray wavelength (Å) (Because it is CuKα ray, λ = 1.54)

The details of the measurement conditions were as follows.
X-ray diffractometer: PANalytical multipurpose X-ray diffractometer X'Pert Powerer
Goniometer: PANalytical high-precision sample horizontal goniometer Sampling width: 0.0131 °
Step time: 0.335 seconds Divergence slit: Programmable divergence slit Incident side scattering slit: None Incident side solar slit: 0.04 °
Incident side mask: 10 mm
Light receiving side scattering slit: 8 mm
Light receiving side solar slit: 0.04 °
Tube: Cu
Tube voltage: 45kV
Tube current: 40mA

As long as the same result as the above method can be obtained, another method may be adopted.

[Calculation of crystallite size ratio]
By dividing the crystallite size of the (1 1 1) plane by the crystallite size of the (0 2 0) plane from the crystallite size of each plane obtained by the above method, the (1 1 1) plane and the (0 2) plane 0) Calculate the ratio of crystallite size to the plane.

[Rate of change in interplanar spacing of crystal lattice planes]
The diketopyrrolopyrrole pigment fine particles according to the present invention have a value at 80 ° C. and 230 of the interplanar spacing of the crystal lattice planes corresponding to the maximum peak at 2θ = 3 to 10 ° calculated by the X-ray diffraction pattern before and after heating. The rate of change of the value at ° C. (according to the following specific formula) is preferably 3.0% or less. It is more preferably 2.0% or less, and particularly preferably 1.5% or less.
Rate of change between the value at 80 ° C and the value at 230 ° C =
{(Surface spacing at 230 ° C) / (Surface spacing at 80 ° C) x 100} -100 (%) [Specific formula]

Here, C.I. I. In Pigment Red 254 and brominated diketopyrrolopyrrole, 2θ = 7.4 ° ± 0.3 ° has the maximum peak at 2θ = 3-10 ° and corresponds to the (020) plane. The (020) plane is a plane substantially perpendicular to the long axis of the crystal lattice, and the rate of change of the plane spacing due to heating is the largest as compared with other crystal lattice planes, so that the crystal structure described later is stable. It will be an indicator of what to do.

Other diketopyrrolopyrrole pigments also include C.I. I. Similar to Pigment Red 254 and brominated diketopyrrolopyrrole, the plane corresponding to the maximum peak at 2θ = 3 to 10 ° is almost perpendicular to the long axis of the crystal lattice, and is heated compared to other crystal lattice planes. Since the rate of change of the interplanar spacing is the largest, it is an index of whether the crystal structure is stable.

The production of a color filter involves a step of heating the pigment, and the deterioration of the color characteristics due to the heating occurs more or less. Specifically, there are problems such as hue shift, contrast and brightness reduction due to heating.
On the other hand, in the pigment fine particles according to the present invention, by setting the rate of change of the surface spacing to 3.0% or less, deterioration of color characteristics due to heating can be suppressed, and a higher quality color filter can be obtained. ..

In the present invention, a mechanism for obtaining a color filter having excellent optical characteristics by using pigment fine particles having a small rate of change in interplanar spacing of the crystal lattice plane, and a pigment fine particle having a small crystallite size and an aspect ratio of a crystallite size are small. The mechanism by which the rate of change in interplanar spacing of the crystal lattice plane can be reduced by the pigment fine particles is not completely clear, but it is presumed as follows.

In most cases, the change in the crystal lattice spacing due to heating changes in the direction in which the plane spacing increases. As the interplanar spacing increases, the area of the crystal grain boundaries between the crystallites increases, and as described above, it becomes primary particles that easily scatter light, and it is presumed that pigment fine particles tend to cause a decrease in contrast and brightness. ..
In addition, the large rate of change in the interplanar spacing due to heating means that the crystal structure is not stable, the crystal structure changes due to heating, and the hue shift occurs due to the interaction of the electron orbits of adjacent molecules. It is also speculated that it will occur.

In general, the reason why the rate of change in interplanar spacing due to heating increases is considered to be that many unstable elements are contained in the crystal structure. Examples of unstable elements of the crystal structure include impurities, non-crystalline components, and distortion of the crystal structure.
If the crystallite size is different or the aspect ratio of the crystallite is large, it is considered that there is distortion in the crystal structure and many unstable amorphous structures are contained in the adjacent part of the crystallite, and the crystal is crystallized by heating. It is speculated that the structure changes and the interaction of the electron orbits of adjacent molecules leads to a hue shift. It is also conceivable that the unstable amorphous structure crystallizes by heating to generate foreign matter. On the other hand, since the pigment fine particles of the present invention have small crystallites and are close to a sphere, the distortion of the crystal structure is small, the crystal structure is dense and stable, the change in the crystal structure due to heating is suppressed, and the rate of change in the interplanar spacing is small. Guessed.

In the case of the pigment fine particles according to the present invention having a specific crystallite size or a specific crystallite size ratio, the crystal grain boundaries that cause unstable elements of the crystal structure are suppressed to be small, and the crystallites are densely aggregated. It is considered that the crystal structure is stable and stable. Therefore, the rate of change in surface spacing due to heating can be kept within the above range, for example, 3.0%. That is, it can be said that the pigment has a stable crystal structure with a small rate of change in surface spacing due to heating.

The method for measuring the rate of change in the interplanar spacing of the crystal lattice planes due to heating is as follows.
(1) Similar to the above-mentioned [Measurement of crystallite size], powder X-ray diffraction measurement by heating using CuKα rays is performed in a Bragg angle (2θ) range of 5.3 ° to 50 °.
Specifically, the X-ray diffraction pattern is first measured at 25 ° C., then the temperature is raised to 80 ° C. and the temperature is maintained for 10 minutes, and then the X-ray diffraction pattern at 80 ° C. is measured. Further, the temperature is raised to 230 ° C. and the temperature is maintained for 10 minutes, and then the X-ray diffraction pattern at 230 ° C. is measured.
(2) From the X-ray diffraction pattern obtained in (1), a diffraction pattern with the background removed is obtained. The background is removed by connecting the bragg angles (2θ) of the above measurement pattern near 5.3 °, around 6.5 °, around 10 °, and around 37.5 ° with straight lines to form the background. The operation is to obtain a pattern obtained by removing the value of the X-ray diffraction intensity represented by this background from the value of the X-ray diffraction intensity obtained in (1).
(3) From the X-ray diffraction pattern obtained in (2) with the background removed, PANalytical data analysis software HighScorePlus Ver. Using 3.0e (3.0.5), fitting the peak shape as the Pseudo Voigt function is performed, and the Bragg angle (2θ) = 7 which is a characteristic diffraction peak of the (020) plane according to the following Bragg's equation. . Calculate the surface spacing of diffraction peaks near 4 ° ± 0.3 °.
2dsinA = nλ
here,
d: Surface spacing (Å)
A: Diffraction peak Bragg angle 2θ (rad)
λ: X-ray wavelength (Å) (Because it is CuKα ray, λ = 1.54)
n: From the results of the surface spacing of the (020) planes at 80 ° C. and 230 ° C. obtained by integers (4) and (3), the rate of change of the plane spacing due to these temperature changes is calculated from the following specific formula. ..
Rate of change between value at 80 ° C and value at 230 ° C = {(plane spacing at 230 ° C) / (plane spacing at 80 ° C) x 100} -100 (%) [Specific formula]
The details of the measurement conditions are the same as in the above-mentioned [Measurement of crystallite size].
As long as the same result as the above method can be obtained, another method may be adopted.

[Primary particle size]
The diketopyrrolopyrrole pigment fine particles in the third embodiment of the present invention have a primary particle size of 5 to 40 nm. Further, the diketopyrrolopyrrole pigment fine particles according to the first, second and fourth forms of the present invention also preferably have a primary particle diameter of 5 to 40 nm. In any case, the primary particle size is more preferably 10 to 30 nm, and particularly preferably 15 to 25 nm.
Further, the standard deviation of the primary particle size is preferably less than 7.0, more preferably less than 6.0, and particularly preferably less than 4.0.
Further, the coefficient of variation of the primary particle size (CV value: hereinafter referred to as “CV value”) is preferably less than 30, more preferably less than 28, and particularly preferably less than 25.

A pigment dispersion having high contrast can be obtained by setting the primary particle size of the diketopyrrolopyrrole pigment fine particles to the above upper limit value or less. On the other hand, by setting the primary particle size of the diketopyrrolopyrrole pigment fine particles to the above lower limit value or more, the viscosity when the dispersion is adjusted can be suppressed to a low level, and the change in viscosity with time can also be suppressed.
In the case of diketopyrrolopyrrole pigment fine particles having a primary particle size exceeding the above upper limit value, the contrast may be lowered, and the performance required for color filter applications may not be satisfied. In the case of diketopyrrolopyrrole pigment fine particles having a primary particle size less than the above lower limit, it becomes difficult to disperse the pigment fine particles in a dispersion medium, and a dispersant, a binder resin, a pigment derivative, etc. Since the amount of the compound added is very large, it tends to be difficult to apply the pigment dispersion to a color filter.

By setting the standard deviation of the primary particle size of the diketopyrrolopyrrole pigment fine particles to the above upper limit value or less, a pigment dispersion having particularly high contrast and low viscosity and having a small change in viscosity with time can be obtained.
When the standard deviation of the primary particle size exceeds the upper limit value, the contrast of the pigment dispersion is likely to be lowered due to the presence of a large number of primary particles having irregular sizes and shapes.

By setting the CV value of the primary particle size of the diketopyrrolopyrrole pigment fine particles to the above upper limit or less, a pigment dispersion having particularly high contrast and low viscosity and having a small change in viscosity with time can be obtained.
When the CV value of the primary particle diameter exceeds the upper limit, the contrast of the pigment dispersion is likely to be lowered due to the presence of a large number of primary particles having irregular sizes and shapes.

Here, the primary particle size is a particle size calculated from an image obtained by observation with an electron microscope. The method for measuring the primary particle size, its standard deviation, and the CV value is as follows.
10 parts by weight of the pigment fine particles according to the present invention, 5 parts by weight of "BYKLPN6919" (manufactured by Big Chemie) as a dispersant, and C.I. I. 1 part by weight of the sulfonated derivative of Pigment Red 254 and 70 parts by weight of propylene glycol monomethyl ether acetate as an organic solvent as a dispersion medium are stirred and mixed with a paint shaker (manufactured by Asada Iron Works Co., Ltd.) and dispersed for 6 hours to disperse the pigment dispersion. Got This pigment dispersion is diluted 50 to 200 times with propylene glycol monomethyl ether acetate, and the diluted solution is treated with an ultrasonic homogenizer (Ultrasonic Cleaner US-105, manufactured by SND Co., Ltd.) for 5 minutes, and then the particles. The image was observed. This observation was performed using an S-5200 type electric field emission scanning electron microscope (manufactured by Hitachi High-Technologies Co., Ltd.) at an acceleration voltage of 20 kV at an observation magnification of 1 million times, and 100 particles that can be clearly identified from the observed image. The major axis was measured using SEM image analysis software (Scandium manufactured by OLYMPUS), and the primary particle diameter, its standard deviation, and the CV value were calculated.

[Content of diketopyrrolopyrrole compound]
The pigment fine particles according to the first embodiment of the present invention contain 90% or more of the compound represented by the general formula (I). By containing the compound represented by the general formula (I) in such a high concentration, the coloring power and the brightness can be kept high.
In order to reduce the size of the crystals of the pigment fine particles, for example, it is conceivable to add a component that suppresses particle growth (for example, a pigment derivative as described in Patent Document 5), and such a component is added. Then, it becomes difficult to keep the coloring power and the brightness high. On the other hand, the pigment fine particles according to the first embodiment of the present invention have a coloring power by keeping the content of the compound represented by the general formula (I) as high as 90% or more other than the components such as the pigment derivative. And the brightness can be kept high.
Further, also in the pigment fine particles according to the second and third forms of the present invention, in order to maintain high coloring power and brightness, the content of the compound represented by the general formula (I) is set to 90% or more. Can and is desirable to do so.
Also in the pigment fine particles according to the fourth aspect of the present invention, the content of brominated diketopyrrolopyrrole represented by the formula (III) can be 90% or more, and it is desirable to do so.

The content of the diketopyrrolopyrrole pigment compound represented by the general formula (I), the general formula (II), and the formula (III) can be specified as follows.
The solvent extract of the pigment fine particles according to the present invention is subjected to LC-MS analysis or NMR analysis to identify the contained components and further quantitatively analyze them.
More specifically, the pigment fine particles are dissolved in an organic solvent such as tetrahydrofuran (hereinafter referred to as "THF"), liquid chromatographically separated by LC-MS, and molecular weight analysis is performed. In addition, the insoluble material is analyzed by molecular weight with a solid direct introduction probe. These are methods for identifying each component based on the molecular weight information of the whole or part of the molecule. Furthermore, quantitative analysis can be performed by comparing with the diketopyrrolopyrrole pigment compounds represented by the general formulas (I), general formulas (II), and formulas (III), which are the components of the pigment fine particles, and the standard of the identification component. it can.
Further, the pigment fine particles can be dissolved in deuterated dimethylsulfoxide or heavy sulfuric acid, each component can be identified by NMR measurement, and quantified from the area ratio of the NMR spectrum.

[Performance of Pigment Fine Particles According to the Present Invention]
The pigment fine particles according to the present invention described above have excellent optical properties. Specifically, the contrast of a cured film having a chromaticity x = 0.6500 can be 7,000 or more, more preferably 8,000 or more, and even 10,000 or more. Further, the film thickness for setting the chromaticity x = 0.6500 can be 2.80 μm or less, particularly 2.70 μm or less, and further 2.60 μm or less. Further, when the chromaticity x = 0.6500 and y = 0.3230, the brightness becomes 18.00 or more and further 19.00 or more, and a color filter having extremely excellent optical characteristics can be obtained. The production of the cured film will be described later.

Here, the contrast is one of the indexes of the color characteristics of the pigment, and it is preferable that the contrast is high because the color development becomes vivid when used for an optical material such as a display. To measure the contrast, light is applied to the cured film sandwiched between two polarizing plates, and the light is transmitted when the polarizing surfaces of the front polarizing plate and the rear polarizing plate are parallel and perpendicular. The amount of light is measured using a contrast measuring device (CT-1 manufactured by Tsubosaka Electric Co., Ltd.), and the transmitted light is defined as the brightness on the polarizing plate, and the brightness when the polarizing planes of the polarizing plate are parallel to the brightness when the polarizing plane is perpendicular to the polarizing plate. The ratio of is calculated as contrast {(contrast) = (brightness when the polarizing planes of the polarizing plate are parallel) / (brightness when the polarizing planes of the polarizing plate are orthogonal)}.

Further, if the film thickness of the cured film can be reduced to the same chromaticity, the photosensitive coloring composition can be saved, and when the film thickness is adjusted to the same, a cured film having high coloring power can be obtained. Therefore, it is preferable. The film thickness is measured using a non-contact surface / layer cross-sectional shape measurement system (R5300G-Lite manufactured by Ryoka System Co., Ltd.).

The heat resistance is indicated by the rate of change in contrast {(contrast before the post-baking process-contrast after the post-baking process) / contrast after the post-baking process x 100 (%)}.

In addition, the number of coarse particles that can be confirmed when the cured film is observed with an optical microscope at a magnification of 500 can be suppressed to 50 or less, and further to 20 or less.

Further, the brightness is one of the indexes of the color characteristics of the pigment as well as the contrast, and the higher the contrast and the brightness value, the more vivid the color is when used for an optical material such as a display, and the light amount of the backlight is suppressed. It is said that it is preferable because it can be used. The brightness was measured by using a spectrophotometer (LCF-1100 manufactured by Otsuka Electronics Co., Ltd.) on the cured film.

The mechanism by which the pigment fine particles according to the present invention having a specific crystallite size or a specific crystallite size ratio can provide a color filter having extremely excellent optical characteristics as described above is not completely clear. As described above, for example, the crystallite size is controlled to 140 Å or less for the crystallite size in the plane α direction and 80 Å or less for the crystallite size in the plane β direction, and the ratio of crystallite size is controlled, for example. By controlling the range from 0.8 to 1.25, it is presumed that the occurrence of crystal strain and the like is suppressed, the structure is stable, and there is little change when heated (heating). Performance improvement by reducing changes due to).
In addition, it is presumed that the suppression of the effects of light scattering and the like on the crystal interface contributes (optical effects of grain boundaries).
Furthermore, the ratio of the size of the crystallite to the size of the crystallite contributes to the presence of the primary particle in a good state in the cured film by making the size and shape of the primary particle small and isotropic. It is presumed that there is (the effect of the state of the primary particles in the cured film).
It is presumed that these plurality of elements achieve the excellent effect of the present invention by a synergistic effect, which is extremely difficult to achieve from the prior art.

The content of the diketopyrrolopyrrole pigment compound represented by the general formula (I), the general formula (II), and the formula (III) in the cured film such as a color filter or the photosensitive coloring composition can be specified. , Can be done as follows.
The solvent extract of the cured film or the photosensitive coloring composition is subjected to LC-MS analysis or NMR analysis to identify the contained components and further quantitatively analyze them.
More specifically, the cured film or the photosensitive coloring composition is dissolved in an organic solvent such as THF, liquid chromatographically separated by LC-MS, and molecular weight analysis is performed. In addition, the insoluble material is analyzed by molecular weight with a solid direct introduction probe. Furthermore, it is compared with the diketopyrrolopyrrole pigment compounds represented by the general formulas (I), the general formulas (II), and the formulas (III), which are the components of the cured film and the photosensitive coloring composition, and the standard of the identification component. Can be quantitatively analyzed.
Further, the cured film or the photosensitive coloring composition can be dissolved in deuterated dimethylsulfoxide or heavy sulfuric acid, each component can be identified by NMR measurement, and quantified from the area ratio of the NMR spectrum.

〔Production method〕
The method for producing the diketopyrrolopyrrole pigment fine particles according to the present invention is not particularly limited, but a so-called salt milling method, a so-called reprecipitation method, or a method for refining an organic pigment by combining a salt milling method and a reprecipitation method may be used. It can be manufactured by using the various conventional techniques described above.

Above all, it is relatively easy to control the crystallite size and primary particle size, and it is manufactured using the reprecipitation method, which has a low risk of causing distortion of pigment crystals due to excessive energy injection, such as the salt milling method. It is preferable to do so.
Among the reprecipitation methods, a solution in which an organic pigment is dissolved in a good solvent (hereinafter, also referred to as “pigment solution”) and a poor solvent for the organic pigment that is compatible with the good solvent (hereinafter, also referred to as “poor solvent”). It is desirable to carry out the production by a continuous reactor in which the above is continuously supplied to the reaction field, and the pigment fine particles precipitated by mixing the two are taken out from the solution to continuously carry out the pigment precipitation reaction.
In particular, a reaction device (hereinafter, also referred to as a "fluid treatment device") in which the pigment solution and the poor solvent are continuously mixed between the relatively rotating processing surfaces that can approach and separate from each other is used. It is most preferable that the mixing is carried out. The reactor is formed between processing surfaces that rotate relatively in a state where they can approach and separate from each other, and the pigment solution and the poor solvent are mixed in a special environment of a thin film fluid forced by the treatment surface. It mixes and precipitates pigment fine particles, which sets it apart from conventional microreactors and other mixing and stirring devices. Further, the pigment solution and the poor solvent are mixed at a minute interval between the processing surfaces that rotate relatively in a state where they can approach and separate from each other, and the influence of gravity can be substantially eliminated. Furthermore, it is preferable that the pigment fine particles are precipitated using the reaction apparatus under laminar flow conditions rather than turbulent flow conditions.

The reason why such a method is preferable is considered as follows.
First, in the case of a method of mechanically pulverizing a pigment such as the salt milling method, the crystallite size is 140 Å or less for the crystallite size in the plane α direction and 80 Å for the crystallite size in the plane β direction. It is necessary to apply a very large force to reduce it to the following range. In addition, since crystal growth occurs at the same time as pulverization, it is necessary to create a state in which the reaction is in equilibrium, which is difficult to control and poor in productivity. In the case of the reprecipitation method, it is easier to control the particle size because the pigment is once dissolved. However, even in the case of the reprecipitation method, it is not easy to control the crystallite size. As the reaction is continued, crystals gradually grow, which must be prevented. Therefore, it is considered important to promptly contact the pigment solution and the poor solvent in the reaction field to generate a large amount of small crystallite-sized particles. Therefore, the diffusion coefficient in the reaction field is important. Therefore, it is considered desirable to use a continuous reactor that continuously supplies the pigment solution and the poor solvent to the reaction field and continuously recovers the pigment fine particles produced. In particular, if a reaction device of a type in which the pigment solution and the poor solvent are continuously mixed between relatively rotating processing surfaces that can approach and separate from each other is used, the diffusion coefficient in the reaction field becomes large. Therefore, it is considered that a large amount of crystal nuclei are generated, and fine crystallite pigment fine particles can be efficiently obtained.

In the reprecipitation method, in particular, in the method of continuously precipitating the pigment fine particles between the relatively rotating processing surfaces that can be approached and separated, the obtained pigment fine particles are very fine and each one. It was found that particles can be produced uniformly and the crystallite size and its distribution can be small. That is, the obtained pigment fine particles are extremely fine pigment fine particles having few coarse particles and a uniform particle size, and the occurrence of crystal distortion and the like is suppressed. This is because, as described above, the contact between the pigment solution and the poor solvent occurs at an extremely high speed, so that the mass diffusivity of the reaction field becomes large, and a large amount of fine crystallite nuclei are purified to collect fine crystallites. It is presumed that this is because the pigment fine particles that are the body can be obtained and the excessive energy given by the pulverization treatment such as the salt milling treatment is not dropped and the generation of strain can be suppressed.

Since the pigment fine particles obtained by the above method are in a good state such as crystals and there are few coarse particles that inhibit the coloring property, a pigment fine particle dispersion having excellent heat resistance and coloring property can be obtained. In other words, by controlling not only the primary particle size of the pigment fine particles but also the size of the crystallites and their distribution, it is possible to obtain a color filter that maintains excellent performance with improved characteristics such as color characteristics and heat resistance. became.

Specifically, the production of the pigment fine particles according to the present invention by the reprecipitation method can be performed as follows.
First, a diketopyrrolopyrrole pigment base (hereinafter, also referred to as “pigment base”) is dissolved in a good solvent. The pigment base material refers to a pigment before the miniaturization treatment described below. The diketopyrrolopyrrole pigment base is not particularly limited, but known commercially available pigments can also be used, and the above-mentioned methods for producing diketopyrrolopyrrole pigments are disclosed in various prior arts. It is also possible to use a pigment produced by the above method.

Examples of a good solvent for dissolving the diketopyrrolopyrrole pigment base include water, an organic solvent, and a mixed solvent composed of a plurality of them. Examples of the water include tap water, ion-exchanged water, pure water, ultra-pure water, RO water, and the like, and examples of the organic solvent include alcohol solvents, amide solvents, ketone solvents, ether solvents, and aromatic solvents. Examples thereof include solvents, carbon disulfide, aliphatic solvents, nitrile solvents, sulfoxide solvents, halogen solvents, ester solvents, ionic liquids, carboxylic acid compounds, and sulfonic acid compounds. The above solvents may be used alone or in combination of two or more.

Here, an inorganic hydroxide such as sodium hydroxide or potassium hydroxide, a compound such as a metal alkoxide such as sodium methoxide or potassium-tert-butoxide, or a quaternary ammonium compound is allowed to be present in the above-mentioned good solvent. It has been known. In the present invention, it is particularly preferable to add the quaternary ammonium compound to the above-mentioned good solvent. By adding the quaternary ammonium compound to the above-mentioned good solvent, it becomes particularly easy to control the crystallite size and the primary particle size, which are the features of the present invention. Although the mechanism is not clear, the presence of the quaternary ammonium compound in the solvent gives good results for the dissolution and subsequent precipitation of the diketopyrrolopyrrole pigment base, which in turn gives good results for the improvement of color characteristics. It is considered to be.

As the quaternary ammonium compound that can be added, hydroxides such as benzyltrimethylammonium, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, and tetrahexylammonium, chlorides, and bromides can be used. Of these, it is preferable to use a hydroxide from the viewpoint of improving solubility, and it is particularly preferable to use benzyltrimethylammonium hydroxide or tetramethylammonium hydroxide. These can be used alone or in admixture of two or more.
In addition to these, tetradecyldimethylbenzylammonium chloride, tetra-N-butylammonium tribromide, tetrabutylammonium hexafluorophosphate, tetrabutylammonium perchlorate and the like can also be used.

The amount of the quaternary ammonium compound added is preferably 0.1 to 10 molar equivalents with respect to the pigment base, and more preferably 0.3 to 6 molar equivalents with respect to the pigment base. , 0.5-4 molar equivalents are particularly preferred. By adding 0.1 molar equivalent or more to the pigment base, it is advantageous in that the pigment base can be sufficiently dissolved and the generation of coarse particles can be suppressed in the precipitation of the pigment fine particles. .. Further, by suppressing the amount of the pigment base to 10 molar equivalents or less with respect to the pigment base, the amount of the pigment base with respect to the solvent can be optimized, which is preferable in terms of obtaining good productivity, and the decomposition of the molecule of the pigment base is preferable. It is advantageous in that the promotion can be suppressed and the heat resistance and color characteristics can be positively affected.

The method for preparing the pigment solution is not particularly limited, but it is preferable to use a stirrer having a rotating stirring blade. As a matter of course, it is possible to suppress the generation of coarse particles caused by undissolved substances in the pigment solution, and even when two or more kinds of molecules or elements are dissolved, the pigment is dissolved in a more uniform dissolved state. The liquid can be prepared quickly.

By performing the preparation of the pigment solution using a stirrer having a rotating stirring blade, it is possible to obtain a pigment solution having a uniform dissolved state or a molecular dispersed state at the molecular level, and the dissolved state of the pigment solution can be obtained. And it is presumed to improve the cluster formation state.

The stirrer used for preparing the pigment solution is not particularly limited as long as it has a rotating stirrer blade, but in a general stirrer having a rotating stirring blade, the peripheral speed at the tip of the stirring blade is 1 m / m /. sec. It is said that the above is high-speed rotation. 1 m / sec. Although it can be carried out at a low peripheral speed of less than, high-speed rotation is advantageous in terms of shortening the pigment dissolution time and improving the certainty of pigment dissolution. From the viewpoint of suppressing the generation of coarse particles, 1 m / sec. Above, further, 10 m / sec. It is preferable to prepare the pigment solution at the above peripheral speed. As such a stirrer, various dispersers, for example, a high-speed rotary emulsification disperser (manufactured by M-Technique Co., Ltd., product name: Clairemix) are suitable.

The concentration of the diketopyrrolopyrrole pigment base in the pigment solution is preferably high from the viewpoint of productivity. It is more preferably contained in an amount of 3% by weight or more, more preferably 5% by weight or more.

The pigment solution is mixed with the poor solvent to precipitate pigment fine particles. The solvent used for the poor solvent can be selected from the solvents listed as good solvents for dissolving the diketopyrrolopyrrole pigment base, but a solvent having low solubility in the organic pigment contained in the pigment solution is selected. There is a need. Each of these solvents may be used alone, or a plurality of these solvents may be mixed and used. In addition, an acid can be added for the purpose of adjusting the pH and adjusting the particle size and crystallinity. Examples of the acid to be added include carboxylic acids such as formic acid, acetic acid, propionic acid and citric acid, sulfonic acids such as benzenesulfonic acid, cyclohexanesulfonic acid and p-toluenesulfonic acid, salicylic acid, cresol and timole as long as they are organic acids. Phenols and the like can be used. In addition, inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, boric acid, phosphoric acid, hexafluorophosphoric acid, sulfamic acid, and perchloric acid can also be used. These may be used alone or in combination of two or more. By adding an acid, it may be possible to bring about further improvements in color characteristics. Further, also in the preparation of the poor solvent, it is preferable to use a stirrer having the above-mentioned rotating stirring blade as in the preparation of the pigment solution.

The pigment solution and the poor solvent are mixed to precipitate pigment fine particles. As described above, it is preferable that the two are continuously mixed between the relatively rotating processing surfaces that can approach and separate from each other.

The temperature at which the pigment fine particles are precipitated is important for adjusting the primary particle size and controlling the crystallite size. Specifically, finer particles can be precipitated by adjusting the temperatures of both the pigment solution and the poor solvent so that the temperature at the time of precipitation is 50 ° C. or lower. Particularly preferably, the temperature at the time of precipitation is 30 ° C. or lower. When the pigment fine particles are precipitated at a high temperature exceeding 50 ° C., the crystal growth of the pigment fine particles is promoted and coarse particles are precipitated, whereas when the pigment fine particles are precipitated at 50 ° C. or lower, the pigment fine particles are precipitated. It can be inferred that the crystal growth of the fine particles is suppressed, the crystallite size is small, and the primary particle diameter is fine and uniform pigment fine particles are precipitated.

A slurry containing pigment fine particles obtained by mixing the above pigment solution and a poor solvent and precipitating pigment fine particles is prepared by filtering, centrifugation, dialysis, ultrafiltration, or the like to remove the pigment fine particles from the liquid. The pigment fine particles of the present invention can be isolated by taking them out and washing them with various solvents.
The solvent used for washing can be selected from the solvents listed as good solvents for dissolving the above-mentioned diketopyrrolopyrrole pigment precursor. Further, in the cleaning treatment, it is preferable to use a stirrer having the above-mentioned rotating stirring blade. The end point of the washing is not particularly limited, but can be determined by analyzing the pH of the washing liquid, the ions of impurities and organic substances. Further, since the pigment fine particles after cleaning are in a state of containing the solvent used for cleaning at the time of completion of cleaning, it is necessary to perform a treatment of drying or solvent replacement.

The drying method is not particularly limited, and examples thereof include vacuum drying, warm air drying, and freeze drying. By drying, it is possible to obtain a powder of pigment fine particles.

The method of solvent replacement is also not particularly limited, but after the wet cake of pigment fine particles containing the cleaning liquid obtained after the completion of cleaning is put into the target solvent and stirred to make it uniform, filtration, centrifugation, dialysis, and the like are performed again. It is possible to prepare a wet cake of pigment fine particles containing a target solvent by using a method such as ultrafiltration.

It can be said that the precipitation of the pigment fine particles and the cleaning treatment of the precipitated pigment fine particles by the reprecipitation method involves not only the precipitation of the pigment fine particles but also the purification of the pigment base material. It is presumed that impurities such as metals and unreacted substances taken into the pigment fine particles are extracted by dissolving the pigment precursor to the molecular state, and these impurities are removed by washing after the pigment fine particles are precipitated. To. The inventors consider that one of the reasons why the coloring power of the pigment fine particles by the reprecipitation method is superior to that of the salt milling method represented by Patent Documents 1 and 2 is the purification of the pigment substance. There is.

If the amount of Fe contained in the pigment fine particles is large, there is a possibility that the liquid crystal may malfunction due to a decrease in the voltage retention rate when a color filter is manufactured using the pigment fine particles. Further, since the amount of Fe contained in the pigment fine particles is large, the amount of impurities contained in the color filter is large, which not only causes deterioration of color characteristics and coloring power, but also is applied in the post-baking process at the time of producing the color filter described later. It may cause foreign matter to be generated on the film. Therefore, it is necessary to reduce the amount of Fe contained in the pigment fine particles as much as possible. It was found that the amount of Fe can be reduced by the purification action of the pigment precursor by the reprecipitation method described above. Therefore, the Fe content in the pigment fine particles can be suppressed to 35 ppm or less. More preferably, it can be suppressed to 30 ppm or less, and even more preferably to 20 ppm or less.
[Example of manufacturing equipment]

Here, the above-mentioned fluid processing apparatus provided with a relatively rotating processing surface that can be approached and separated will be briefly described with reference to FIGS. 1 to 3. This device is similar to the device described in Patent Document 7.
In FIG. 1, U indicates an upper side and S indicates a lower part, but in the present invention, the upper, lower, front, back, left, and right show only relative positional relationships, and do not specify an absolute position. In FIGS. 2 (A) and 3 (B), R indicates a rotation direction. In FIG. 3B, C indicates the centrifugal force direction (radial direction).

This fluid processing apparatus includes two first and second processing units 10 and 20 that face each other, and at least one of the processing units rotates. The facing surfaces of both processing units 10 and 20 are processing surfaces, respectively. The first processing unit 10 includes a first processing surface 1, and the second processing unit 20 includes a second processing surface 2.

Both treatment surfaces 1 and 2 are connected to the flow path of the fluid (that is, the pigment solution and the poor solvent) and form a part of the flow path of the fluid to be treated. The interval between the surfaces 1 and 2 for both treatments can be appropriately changed, but is usually adjusted to a minute interval of 1 mm or less, for example, about 0.1 μm to 50 μm. As a result, the fluid to be treated passing between the surfaces 1 and 2 for both treatments becomes a forced thin film fluid forced by the surfaces 1 and 2 for both treatments.

When processing a plurality of fluids using this device, the device is connected to the flow path of the first fluid and forms a part of the flow path of the first fluid. Further, this device forms a part of the flow path of the second fluid, which is different from the first fluid. Then, this apparatus performs fluid treatment in which both flow paths are merged, both fluids are mixed and reacted between the treatment surfaces 1 and 2, and fine particles are precipitated.

Specifically, this device includes a first holder 11 that holds the first processing portion 10, a second holder 21 that holds the second processing portion 20, a contact surface pressure applying mechanism, and rotation. It includes a drive mechanism, a first introduction unit d1, a second introduction unit d2, and a fluid pressure applying mechanism p.

As shown in FIG. 2A, in this embodiment, the first processing portion 10 is an annular body, and more particularly, a ring-shaped disc. The second processing unit 20 is also a ring-shaped disc. In this embodiment, both the processing portions 10 and 20 have the first and second processing surfaces 1 and 2 facing each other mirror-polished, and the arithmetic mean roughness is not particularly limited, but is preferable. It is 0.01 to 1.0 μm, more preferably 0.03 to 0.3 μm.

At least one of the first holder 11 and the second holder 21 can be rotated relative to the other holder by a rotation drive mechanism (not shown) such as an electric motor.
In this embodiment, the second holder 21 is fixed to the device, and the first holder 11 attached to the rotation shaft 50 of the rotation drive mechanism also fixed to the device rotates and is supported by the first holder 11. The first processing unit 10 is rotated with respect to the second processing unit 20. Of course, the second processing unit 20 may be rotated, or both may be rotated.

In this embodiment, the second processing portion 20 approaches and separates from the first processing portion 10 in the direction of the rotation shaft 50, and the accommodating portion 41 provided in the second holder 21 has a second position. 2 The portion of the processing portion 20 opposite to the processing surface 2 side is accommodated so as to appear and disappear. However, on the contrary, the first processing unit 10 may approach / separate from the second processing unit 20, and both processing units 10 and 20 approach / separate from each other. It may be one.

The accommodating portion 41 is a recess for accommodating a portion of the second processing portion 20 opposite to the processing surface 2 side, and is a groove formed in an annular shape. The accommodating portion 41 accommodates the second processing portion 20 with a sufficient clearance so that a portion of the second processing portion 20 opposite to the processing surface 2 side can appear and disappear. The second processing unit 20 may be arranged so that it can only move in parallel in the axial direction, but by increasing the clearance, the second processing unit 20 may be arranged with respect to the accommodating unit 41. The center line of the processing portion 20 may be tilted and displaced so as to break the relationship parallel to the axial direction of the accommodating portion 41, and further, the center line of the second processing portion 20 and the accommodating portion 41 may be displaced. It may be possible to displace the center line so as to be displaced in the radial direction. In this way, it is desirable to hold the second processing unit 20 by a floating mechanism that holds the second processing portion 20 so as to be three-dimensionally displaceable.

The above fluid is in a state where pressure is applied by a fluid pressure applying mechanism p composed of a pump, potential energy, etc., between the first introduction unit d1 and the second introduction unit d2 between the surfaces 1 and 2 for both treatments. be introduced. In this embodiment, the first introduction portion d1 is a passage provided in the center of the annular second holder 21, and one end thereof is a surface for both treatments from the inside of the annular treatment portions 10 and 20. Introduced between 1 and 2. The second introduction unit d2 supplies the second fluid, which reacts with the first fluid, to the processing surfaces 1 and 2. In this embodiment, the second introduction portion d2 is a passage provided inside the second processing portion 20, and one end thereof is an opening d20 formed on the second processing surface.
The first fluid pressurized by the fluid pressure applying mechanism p is introduced from the first introduction section d1 into the space inside both the treatment sections 10 and 20, and the first treatment surface 1 and the second treatment surface 1 and the second treatment surface. It passes between 2 and tries to pass through to the outside of both processing portions 10 and 20.
When a second fluid pressurized by the fluid pressure applying mechanism p is supplied from the second introduction unit d2 between these processing surfaces 1 and 2, and merges with the first fluid, and both fluids are mixed. By the precipitation reaction between the pigment solution and the poor solvent, the pigment fine particles are precipitated, and the fluid containing the pigment fine particles is discharged from the surfaces 1 and 2 for both treatments to the outside of the treatment portions 10 and 20. ..

The above-mentioned contact pressure applying mechanism applies a force that acts in a direction in which the first processing surface 1 and the second processing surface 2 are brought close to each other to the processing portion. In this embodiment, the contact pressure applying mechanism is provided on the second holder 21 and urges the second processing portion 20 toward the first processing portion 10.

The contact surface pressure applying mechanism is a force that pushes the first processing surface 1 of the first processing unit 10 and the second processing surface 2 of the second processing unit 20 in a direction in which they approach each other (hereinafter, contact pressure). It is a mechanism for generating). By balancing this contact pressure with the force that separates the surfaces 1 and 2 for both treatments due to the fluid pressure, the distance between the surfaces 1 and 2 for both treatments is maintained at a predetermined minute distance, in units of nm or μm. Generates a thin film fluid with a minute film thickness. The contact pressure may be the elastic force of the spring 43, the pressure of the urging fluid such as air or oil introduced into the urging fluid introduction portion 44, or other force such as magnetic force or gravity. ..

Against the urging force of the contact surface pressure applying mechanism, the second processing unit 20 is subjected to the first processing unit 10 due to the separation force generated by the pressure and viscosity of the fluid pressurized by the fluid pressure applying mechanism p. Move away from and leave a small gap between the two treatment surfaces. In this way, the distance between the first processing surface 1 and the second processing surface 2 is set with an accuracy of μm unit by the balance between the contact surface pressure and the separation force.
The separation force includes the fluid pressure and viscosity of the fluid, the centrifugal force due to the rotation of the processing portion, the negative pressure when a negative pressure is applied to the urging fluid introduction portion 44, and the spring 43 as a pulling spring. The elastic force in the case of the above can be mentioned. This contact surface pressure applying mechanism may be provided not in the second processing unit 20 but in the first processing unit 10, or may be provided in both.

As shown in FIG. 2, a groove-shaped recess 13 extending from the center side of the first processing portion 10 to the outside, that is, in the radial direction is formed on the first processing surface 1 of the first processing portion 10. It may be carried out. As shown in FIG. 2B, the planar shape of the recess 13 may be curved or spirally extending on the first processing surface 1. Further, the recess 13 can be formed on the second processing surface 2 or can be formed on both the first and second processing surfaces 1 and 2. By forming such a recess 13, a micropump effect can be obtained, and there is an effect that the fluid can be sucked between the first and second processing surfaces 1 and 2.

It is desirable that the base end of the recess 13 reaches the inner circumference of the first processing portion 10. The tip of the recess 13 extends toward the outer peripheral surface side of the first processing portion surface 1, and the depth thereof gradually decreases from the base end toward the tip.
A flat surface 16 without the recess 13 is provided between the tip of the recess 13 and the outer peripheral surface of the first processing surface 1.

The above-mentioned opening d20 is preferably provided at a position facing the flat surface 16 of the first processing surface 1.
In particular, the flat surface 16 on the downstream side (outside in this example) of the point where the flow direction when introduced by the micropump effect is converted into the flow direction of the laminar flow in a spiral shape formed between the processing surfaces. It is desirable to install it in a position facing the.
Specifically, in FIG. 2B, it is preferable that the distance n in the radial direction from the tip of the recess 13 provided on the first processing surface 1 is about 0.5 mm or more. This makes it possible to mix a plurality of fluids and precipitate fine particles under laminar flow conditions.

The shape of the opening d20 may be a circular shape as shown in FIGS. 2 (B) and 3 (B), and a processing surface which is a ring-shaped disk as shown by a dotted line in FIG. 2 (B). It may have a concentric ring shape surrounding the central opening of 2.
In order to easily obtain pigment fine particles in which the crystallite size and the primary particle size of the present invention are controlled, the shape of the opening d20 should be a concentric ring shape surrounding the central opening of the processing surface 2. , More preferred. The two fluids come into contact with each other quickly, the concentration distribution of both fluids in the reaction field between the treatment surfaces is suppressed, and the mixed state becomes more uniform, so that the degree of progress of the precipitation reaction becomes more uniform, and the obtained pigment fine particles also crystallize. It is presumed that the child size and the primary particle size become more uniform.

The second introduction unit d2 can have a directionality. For example, as shown in FIG. 3A, the introduction direction of the second processing surface 2 from the opening d20 is inclined at a predetermined elevation angle (θ1) with respect to the second processing surface 2. .. This elevation angle (θ1) is set to more than 0 degrees and less than 90 degrees, and in the case of a reaction having a faster reaction speed, it is preferably set to 1 degree or more and 45 degrees or less.

Further, as shown in FIG. 3B, the introduction direction of the second processing surface 2 from the opening d20 has directionality in the plane along the second processing surface 2. .. The introduction direction of the second fluid is the outward direction away from the center in the radial component of the processing surface, and the component with respect to the rotation direction of the fluid between the rotating processing surfaces. Is in the forward direction. In other words, it has a predetermined angle (θ2) from the reference line g to the rotation direction R, with the line segment in the radial direction passing through the opening d20 and the outward direction as the reference line g. This angle (θ2) is also preferably set to more than 0 degrees and less than 90 degrees.

This angle (θ2) can be changed and carried out according to various conditions such as the reaction speed, the viscosity, and the rotation speed of the processing surface. Further, it is possible to give the second introduction unit d2 no directionality at all.

In the example of FIG. 1, the number of the above-mentioned flow paths is two, but may be three or more. In the example of FIG. 1, the second fluid is introduced between the processing surfaces 1 and 2 from the second introduction unit d2, but this introduction unit may be provided in the first processing unit 10 or both. Good. Further, a plurality of introduction portions may be prepared for one type of fluid. Further, the shape, size, and number of the introduction openings provided in each processing portion are not particularly limited and may be appropriately changed. Further, an opening for introduction may be provided immediately before or further upstream of the first and second processing surfaces 1 and 2.

The control of the crystallite size to crystallite size ratio by the production method and the reactor described above includes various parameters for controlling the reaction rate in the reaction field, such as temperature, distance between processing surfaces, fluid supply, and control. This is possible by controlling the discharge rate and the like, feeding back from the crystallite size of the obtained pigment fine particles, and selecting the optimum value for each device.

[Pigment dispersion]
In the present invention, a pigment dispersion can be obtained by putting the diketopyrrolopyrrole-based pigment fine particles according to the present invention described above into an organic solvent as a dispersion medium and subjecting them to dispersion treatment. The organic solvent is usually preferably an ester-based organic solvent. The ester-based organic solvent used here is not particularly limited, but a high boiling point organic solvent having a boiling point of preferably 100 ° C. or higher, more preferably 110 ° C. or higher, still more preferably 130 ° C. or higher is preferable. Examples of such high boiling point organic solvents include ethylene glycol monomethyl ether propionate, ethylene glycol monoethyl ether propionate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether propionate, and ethylene glycol monomethyl ether acetate. Examples thereof include ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, and diethylene glycol monobutyl ether acetate (BCA).
Among the above ester-based organic solvents, propylene glycol monomethyl ether acetate (boiling point: 146 ° C.) and propylene glycol monomethyl ether (boiling point: 120 ° C.) are more preferable from the viewpoint of dispersibility of the organic pigment. The above ester-based organic solvent can be used alone or in combination of two or more.

In addition, a dispersant can be added as needed. The dispersant is not particularly limited, but for example, mainly in an organic solvent system, carboxylic acid esters such as polyurethane and polyacrylate, unsaturated polyamides, polycarboxylic acid (partial) amine salts, polycarboxylic acid ammonium salts, and polycarboxylic acid alkyls. Amine salts, polysiloxanes, long-chain polyaminoamide phosphates, hydroxyl group-containing polycarboxylic acid esters, and modified products of these, amides formed by the reaction of poly (lower alkyleneimine) with polyesters having free carboxylic acid groups. And its salts; mainly aqueous (meth) acrylic acid-styrene copolymer, (meth) acrylic acid- (meth) acrylic acid ester copolymer, styrene-maleic acid copolymer, polyvinyl alcohol, polyvinylpyrrolidone, etc. Sodium lauryl sulfate, polyoxyethylene alkyl ether sulfate, sodium dodecylbenzene sulfonate, alkali salt of styrene-acrylic acid copolymer, sodium stearate, sodium alkylnaphthalene sulfonate, Sodium alkyldiphenyl ether disulfonate, monoethanolamine lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene Anionic surfactants such as alkyl ether phosphate; polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ether phosphate, polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate, etc. Nonionic surfactants; alkyl betaines such as alkyldimethylaminoacetate betaine and amphoteric surfactants such as alkyl imidazoline can be mentioned, and these can be used alone or in admixture of two or more.

Among these, a dispersant having an amine structure is particularly excellent in dispersibility and is preferably used. Examples of the dispersant having such an amine structure include Solspace series manufactured by Lubrizol, Disperbyk series manufactured by Big Chemie, Efka series manufactured by BASF, and Ajisper series manufactured by Ajinomoto Fine-Tech. The amount of the dispersant is usually 100 parts by weight or less, preferably 50 parts by weight or less, and more preferably 30 parts by weight or less with respect to 100 parts by weight of the pigment.

In addition, a binder resin can be added together with the dispersant. Examples of the binder resin include phenol resin, alkyd resin, polyester resin, amino resin, urea resin, melamine resin, guanamine resin, epoxy resin, styrene resin, vinyl resin, vinyl chloride resin, vinyl chloride / vinyl acetate copolymer resin, and the like. Acrylic resin, polyurethane resin, silicone resin, polyamide resin, polyimide resin, rubber resin, cyclized rubber, maleated oil resin, butyral resin, polybutadiene resin, cellulose resin, chlorinated polyethylene, chlorinated polypropylene, etc. Can be mentioned. These binder resins can be used alone or in combination of two or more. The binder resin can also be added when obtaining the photosensitive coloring composition described later.

Further, if necessary, a compound such as a known pigment derivative may be added. These compounds are compounds that mediate between the pigment and the dispersant, and are considered to have a function of physically, electrically, and chemically adsorbing between the pigment surface and the dispersant to improve dispersion stability. ing. Examples of such pigment derivatives include diketopyrrolopyrrole-based, anthraquinone-based, phthalocyanine-based, metal phthalocyanine-based, quinacridone-based, azochelate-based, azo-based, isoindolinone-based, pyranthron-based, indanslon-based, and anthrapyrimidine-based , Dibromoanthanthrone type, flavanthron type, perylene type, perinone type, quinophthalone type, thioindigo type, dioxazine type, etc. Examples thereof include pigment derivatives having a substituent introduced therein. Compounds such as these pigment derivatives may be used alone or in combination of two or more.

Addition of compounds such as dispersants, binder resins, and pigment derivatives to pigment dispersions also contributes to reduction of floculation, improvement of dispersion stability of pigments, and improvement of viscosity characteristics of dispersions.

The above dispersion treatment is not limited to the method and the disperser used for the treatment, but the energy such as an excessive impact force on the pigment fine particles according to the present invention can be adjusted by adjusting the stirring speed and the treatment time during the treatment. Distributed processing is possible without dropping. Therefore, it is possible to use a stirring mechanism such as a ball mill, a bead mill, or a sand mill that disperses the object to be treated by vigorously stirring a medium made of glass, steel, stainless steel, ceramics, zircon, zirconia, or the like. It can be carried out even under conditions that do not involve crushing of fine particles. Further, the dispersion treatment can also be performed by using a disperser that does not use the above media, and in that case, an apparatus similar to the apparatus used for preparing the pigment solution or the poor solvent can be mentioned. By reducing the pulverization of the pigment fine particles without, or even with the pulverization of the pigment fine particles, the homogenization of the pigment fine particles after the dispersion treatment can be improved, and as a result, it contributes to the improvement of the color characteristics. It is advantageous in that it is easy to obtain the effect of being able to do it.

[Photosensitive coloring composition]
At least a monomer and a photopolymerization initiator can be mixed with the pigment dispersion to obtain a photosensitive coloring composition.
The monomer is not particularly limited, and includes monofunctional monomers such as nonylphenylcarbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexylcarbitol acrylate, 2-hydroxyethyl acrylate and N-vinylpyrrolidone. , Bifunctional monomers such as tripropylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate and bisphenol A diacrylate, trifunctional monomers such as trimethylpropan triacrylate and pentaerythritol triacrylate. Examples include monomers, other polyfunctional monomers such as dipentaerythritol penta and hexaacrylate. It is also possible to use two or more kinds of these photopolymerizable monomers.
Photopolymerization initiators include aromatic ketones, loffin dimer, benzoins, benzoin ethers, acetophenones, benzophenones, thioxanthones, ketals, quinones, triazines, imidazoles, oxime esters, and phosphine. , Borates, carbazoles, titanocene, polyhalogens and the like. For example, a combination of 4,4'-bis (diethylamino) benzophenone and 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 4- [pn, N-di (ethoxycarbonylmethyl) -2, 6-di (trichloromethyl) -s-triazine], 2-methyl-4'-(methylthio) -2-morpholinopropiophenone are preferred. These photopolymerization initiators may be used alone, or may be used by mixing two or more kinds at an arbitrary ratio as required.

In addition, the following alkali-soluble resins can also be included in the photosensitive coloring composition.
As the alkali-soluble resin, those generally used for negative resists can be used, as long as they are soluble in an aqueous alkali solution, and are not particularly limited. For example, 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 ( One or more selected from meta) acrylate, styrene, γ-methylstyrene, N-vinyl-2-pyrrolidone, glycidyl (meth) acrylate, etc., and (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, Examples thereof include a copolymer composed of fumaric acid, vinyl acetic acid, and one or more selected from these anhydrides, such as a polymer obtained by adding an ethylenically unsaturated compound having a glycidyl group or a hydroxyl group to the above copolymer. Can also be exemplified. These alkali-soluble resins can also be added when obtaining the pigment dispersion described above.

The photosensitive coloring composition of the present invention may further contain additives such as a filler, an adhesion accelerator, an antioxidant, an ultraviolet absorber, and a leveling agent.

〔Color filter〕
A color filter can be produced by applying, photocuring, and developing the photosensitive coloring composition containing the pigment fine particles according to the present invention described above on a substrate to obtain a coating film. Hereinafter, this process is referred to as a prebaking process. The photosensitive coloring composition is preferably applied onto a glass substrate or a silicon substrate by roll coater, slit coater, spray, bar coater, applicator, spin coater, dip coater, inkjet, or screen printing. .. After coating, it is preferable to dry the organic solvent and heat it from the viewpoint of smoothness and handling of the coating film. The heating temperature is preferably 50 to 140 ° C, more preferably 70 to 90 ° C. The heating time is preferably 0.5 to 60 minutes, more preferably 1 to 10 minutes.
In photo-curing, the coating film is irradiated with ultraviolet rays to cure the coating film. It is preferable that photo-curing is performed in order to leave a pattern on the glass substrate in the subsequent development, and a photomask that prevents ultraviolet rays is placed on the portion to be removed by the development to prevent curing. The photocuring is preferably performed with an ultraviolet irradiation amount of 10 to 100 mJ / cm ^2. In the development, the cured coating film after photocuring is immersed in an alkaline aqueous solution and then rinsed with water to remove the uncured portion. As the alkaline aqueous solution to be used, the concentration of the alkaline agent is preferably 0.001 to 10% by weight, preferably 0.01 to 1% by weight. Further, as the alkaline agent used for development, an aqueous solution of ammonia, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, triethylamine, triethanolamine, tetramethylammonium hydroxide or the like is preferable.
The film thickness of the coating film is adjusted so as to obtain a desired chromaticity. This is because the chromaticity also depends on the film thickness.

The developed coating film is heated to 200 to 300 ° C. to obtain a cured film. Hereinafter, this process is referred to as a post-baking process. By heating the developed coating film, a cured film having excellent hardness can be formed. From the viewpoint of obtaining a cured film having excellent hardness and heat resistance, the heating temperature is preferably 200 to 300 ° C. From the viewpoint of obtaining a cured film having excellent hardness and heat resistance, the heating time is preferably 10 to 300 minutes. Prior to the post-baking step, preheating may be performed at 80-100 ° C. for 10-60 minutes.

Hereinafter, the invention of the present application will be described in more detail with reference to examples, but the invention of the present application is not limited to these examples.

The symbols in the following examples indicate the following contents. Further, the weight% will be described as wt% below. DMSO: dimethyl sulfoxide, NMP: N-methylpyrrolidone, TMAH aq. : 25 wt% tetramethylammonium hydroxide aqueous solution, BTMA soln. : 40 wt% benzyltrimethylammonium hydroxide methanol solution, EG: ethylene glycol, MeOH: methanol.

(Manufacture of brominated diketopyrrolopyrrole)
1. 1. Generation of alkali metal salt of diketopyrrolopyrrole pigment compound In a stainless steel reaction vessel equipped with a perfusion tube, 200 parts of molecular sieve-dehydrated tert-amyl alcohol and 140 parts of sodium-tert-amyl alkoxide were added under a nitrogen atmosphere. , The mixture was heated to 100 ° C. with stirring to prepare an alkali solution. Next, 88 parts of diisopropyl succinate and 153.6 parts of 4-bromobenzonitrile were added to a glass flask and heated to 90 ° C. with stirring to dissolve them to prepare a solution of a mixture thereof. The heated solution of this mixture was slowly added dropwise to the alcoholate solution heated to 100 ° C. at a constant rate over 2 hours with vigorous stirring. After completion of the dropping, heating and stirring were continued at 90 ° C. for 2 hours to obtain an alkali metal salt solution of the diketopyrrolopyrrole pigment compound.

2. Generation of Red Suspension Further, 600 parts of methanol, 600 parts of water and 114 parts of acetic acid were added to a reaction vessel with a glass jacket, and the mixture was cooled to −10 ° C. The cooled mixture was cooled to 75 ° C. using a high-speed stirring disperser while rotating a share disk having a diameter of 8 cm at 4000 rpm, and the alkali metal of the previously obtained diketopyrrolopyrrole pigment compound was obtained. The salt solution was added in small portions. At this time, the addition of an alkali metal salt solution of the diketopyrrolopyrrole pigment compound at 75 ° C. while cooling so that the temperature of the mixture consisting of methanol, acetic acid, and water is always maintained at −5 ° C. or lower. It was added in small portions over approximately 120 minutes, adjusting the rate at which it was applied. After the addition of the alkali metal salt solution, red crystals were precipitated and a red suspension was obtained.

3. 3. Separation of brominated diketopyrrolopyrrole Subsequently, the obtained red suspension was filtered through an ultrafiltration device at 5 ° C. to obtain a red paste. This paste was redistributed in 3500 parts of water at 25 ° C., washed, and filtered with an ultrafiltration device three times. The obtained water paste of the diketopyrrolopyrrole pigment compound is dried at 60 ° C. for 72 hours and pulverized to obtain a pigment base, which is a brominated diketopyrrolopyrrole represented by the formula (III) (hereinafter, "" 150.8 parts (described as "brominated DPP") (having a primary particle size of 40 to 60 nm as observed by STEM, which will be described later) was obtained.

Example 1
Pigment micronization (preparation of pigment solution)
As the solvent used as the base material in Table 2, the DMSO of the raw material 1 was 60 wt% and the TMAH aq of the raw material 2 was added. Add 28 wt%, 9 wt% brominated DPP, and 3 wt% EG of raw material 4, and stir using a high-speed rotary emulsification disperser (manufactured by M Technique Co., Ltd., product name: Clairemix, hereinafter "Clearmix"). The brominated DPP was dissolved. The formulation and preparation conditions are shown in Table 2 together with other examples and comparative examples.

(Preparation of poor solvent)
As the poor solvent, 20 wt% of citric acid of the raw material 2 and 10 wt% of the EG of the raw material 4 were added to 70 wt% of tap water of the raw material 1 in Table 3, and the mixture was mixed using Clairemix to prepare a poor solvent. The formulation and preparation conditions are shown in Table 3 together with other examples and comparative examples.

(Precipitation of pigment fine particles)
A reaction device is used that uniformly diffuses, stirs, and mixes in a thin film fluid formed between the processing surfaces 1 and 2 which are arranged facing each other and can be approached and separated from each other and at least one of them rotates with respect to the other. Then, the prepared pigment solution and the poor solvent were mixed, and the precipitation reaction was continuously carried out in the thin film fluid. Specifically, a poor solvent is sent as the first fluid from the center of the apparatus shown in FIG. 1 (first introduction unit d1), and the pigment solution is used as the second fluid from the second introduction unit d2 for processing surface 1, Introduced between two. The first fluid and the second fluid were mixed in the thin film fluid to precipitate the pigment fine particles dissolved in the pigment solution, and the pigment fine particle dispersion was discharged from the treatment surfaces 1 and 2. The supply pressure of the first fluid and the second fluid, the flow rate of the liquid to be fed, the liquid feed temperature, the rotation speed of the processing unit 10 (hereinafter referred to as the rotation speed), the back pressure, and the temperature of the discharge liquid are used as the conditions for producing the pigment fine particles. It is shown in Table 4 together with other examples and comparative examples. The liquid feeding temperatures of the first fluid and the second fluid are measured immediately before the introduction of the device (more specifically, immediately before the introduction between the treatment surfaces 1 and 2) of the temperatures of the first fluid and the second fluid, respectively. The temperature of the discharged liquid is a measurement of the temperature of the pigment fine particle dispersion liquid immediately after being discharged from the treatment surfaces 1 and 2. Further, as the opening d20 of the second introduction portion d2, as shown by the dotted line in FIG. 2B, a concentric annular shape surrounding the central opening of the processing surface 2 was used.

(Washing / drying)
(A) In order to separate only the pigment fine particles from the pigment fine particle dispersion liquid discharged from the treatment surfaces 1 and 2, the pigment fine particles are loosely aggregated and filtered under reduced pressure (-0.1 MPaG) using a filter paper. Pigment fine particles were collected by filtration.

(B) The obtained wet cake of pigment fine particles is put into 5 L of tap water, stirred and washed with Clairemix at 6000 rpm for 1.5 minutes, and the washed liquid is recovered by vacuum filtration again. The operation was repeated 4 times to obtain a wet cake of pigment fine particles. The obtained wet cake of the pigment fine particles was vacuum-dried to obtain a dry powder of the pigment fine particles. Vacuum drying was performed at 30 ° C. and −0.10 MPaG for 72 hours.
The obtained dry powder of the pigment fine particles was subjected to X-ray diffraction measurement with a multipurpose X-ray diffractometer X'Pert Powerer (manufactured by PANalytical Co., Ltd.), and data analysis software HighScorePlus Ver. Analysis was performed using 3.0e (3.0.5) (manufactured by PANalytical).
Further, ICP quantitative analysis was performed to measure the amount of Fe contained in the pigment fine particles.

Preparation of Pigment Dispersion 10 parts by weight of the dry powder of the obtained pigment fine particles, 5 parts by weight of "BYKLPN6919" (manufactured by Big Chemie) as a dispersant, and C.I. I. 1 part by weight of a sulfonated derivative of Pigment Red 254 (hereinafter, "R254") and 70 parts by weight of propylene glycol monomethyl ether acetate (hereinafter, "PGMEA") as a solvent are stirred and mixed with a paint shaker (manufactured by Asada Iron Works, Ltd.). The dispersion treatment was carried out for 6 hours to obtain a pigment dispersion of brominated DPP. The viscosity of the obtained pigment dispersion was measured. The obtained pigment dispersion was diluted with PGMEA to prepare a dispersion for STEM observation. The obtained dispersion liquid for STEM observation was dropped onto the grid, and STEM observation was performed.

Also, in order to adjust the chromaticity, C.I. I. A pigment dispersion of Pigment Red 177 (hereinafter, “R177”) was prepared. Regarding the pigment dispersion of R177, 10 parts by weight of "Chromofine Red A3B" (manufactured by BASF) as a pigment, 5 parts by weight of "BYKLPN6919" (manufactured by Big Chemie) as a dispersant, and 5 parts by weight as a dispersion aid. The composition was 1 part by weight of the sulfonated derivative of R177 and 70 parts by weight of PGMEA as the solvent, and was prepared in the same manner as the above-mentioned preparation of the pigment dispersion of brominated DPP.

Preparation of Photosensitive Coloring Composition With respect to the pigment dispersion of brominated DPP and the pigment dispersion of R177, each photosensitive coloring composition was prepared by the following production methods.
50 parts by weight of pigment dispersion, 6 parts by weight of acrylic resin ("ZAH-110" manufactured by Soken Kagaku Co., Ltd.), 4 parts by weight of dipentaerythritol hexaacrylate as a polymerizable monomer, 2-methyl-1- as a photopolymerization initiator (4-Methylthiophenyl) -2-morpholinopropane-1-one (BASF "IRGACURE 907") 1 part by weight and 100 parts by weight of PGMEA as a solvent are stirred and mixed so as to be uniform, and then a 1.0 μm filter is used. To obtain a photosensitive coloring composition.

Preparation of cured film The cured film was prepared for the following two types.
Using the photosensitive coloring composition of brominated DPP, a cured film having a chromaticity adjusted so that the chromaticity x = 0.6500 during the post-baking process was prepared, and the coarse particles, contrast, film thickness and heat resistance were measured. Evaluation was performed.
Using the brominated DPP and the photosensitive coloring composition of R177, a cured film whose chromaticity was adjusted so that the chromaticity was x = 0.6500 and y = 0.3230 during the post-baking step was prepared, and the brightness was evaluated. Was done.

1. 1. Pre-baking step The photosensitive coloring composition obtained above was applied onto a glass substrate with a spin coater and then dried at 80 ° C. for 3 minutes to obtain a coating film. A photomask was placed on the obtained coating film, and 100 mJ / cm ² of ultraviolet rays were irradiated using an ultraviolet fiber spot irradiation device. Further, the mixture was vibrated in an alkaline aqueous solution (0.04 wt% potassium hydroxide aqueous solution) and then rinsed with pure water to remove the uncured portion. The rotation speed of the spin coater was changed so as to sandwich the specified chromaticity to prepare three coating films, and the evaluation items of the specified chromaticity could be calculated by the first-order correlation method.

2. Post-baking step The coating film from which the uncured portion was removed was preheated in a dryer at 80 ° C. for 30 minutes, and then main heat treated at 230 ° C. for 30 minutes to obtain a cured film.

Example 2
A cured film was obtained in the same manner as in Example 1 except that the formulation of the pigment solution shown in Table 2, the formulation of the poor solvent shown in Table 3, and the conditions for producing pigment fine particles shown in Table 4 were changed.

Example 3
A cured film was obtained in the same manner as in Example 1 except that the formulation was changed to the poor solvent formulation shown in Table 3.

Example 4
A cured film was obtained in the same manner as in Example 1 except that the conditions for producing pigment fine particles shown in Table 4 were changed.

Example 5
A cured film was obtained in the same manner as in Example 1 except that the formulation of the pigment solution shown in Table 2 was changed.

Example 6
A cured film was obtained in the same manner as in Example 2 except that the formulation of the pigment solution shown in Table 2 and the formulation of the poor solvent shown in Table 3 were changed.

Comparative Example 1
As a comparative example in which the pigment was not micronized, the brominated DPP used as the pigment precursor in Examples 1 to 6 was prepared as a pigment dispersion by the same method as in Example 1 without pigment micronization. After that, a cured film was obtained in the same manner.

Comparative Example 2
As Comparative Example 2, the color characteristics, the primary particle size, and the change thereof of the pigment fine particles produced by pulverization will be described. The step of producing the pigment fine particles by the pulverization method was carried out as follows according to Japanese Patent Application Laid-Open No. 2013-82905 known as a document of the salt milling method.

50 parts by weight of brominated DPP, 550 parts by weight of sodium chloride, and 110 parts by weight of diethylene glycol were charged in a kneader and kneaded at 50 ° C. for 4 hours by a salt milling method to prepare a pigment fine particle kneaded product.

In order to remove impurities from the obtained pigment fine particle kneaded product, the obtained pigment fine particle kneaded product was put into 5 L of tap water, stirred and washed with Clairemix at 6000 rpm for 15 minutes, and after washing. The liquid was filtered under reduced pressure using a filter paper (−0.1 MPaG) to collect pigment fine particles. The wet cake of the pigment fine particles collected by filtration was washed and dried in the same manner as in Example 1. Then, a pigment dispersion was prepared by the same method as in Example 1, and a cured film was obtained in the same manner thereafter.

Comparative Example 3
350 mL of the pigment solution prepared in Example 2 using a burette was added to 35 mL / min. In 5 L of the poor solvent prepared in Example 2 stirred at 1700 rpm using Claremix. The pigment fine particle dispersion was obtained at the same rate as above. In order to separate only the pigment fine particles from the pigment fine particle dispersion, the pigment fine particles are loosely aggregated, and the pigment fine particles are collected by filtration under reduced pressure (-0.1 MPaG) using a filter paper, and the collected pigment fine particles are collected. Wet cake was washed and dried in the same manner as in Example 1. Then, a pigment dispersion was prepared by the same method as in Example 1, and a cured film was obtained in the same manner thereafter.

Evaluation method The crystallite size was measured by the above-mentioned [Measurement of crystallite size], and the ratio of crystallite size was further calculated. In addition, the rate of change in interplanar spacing was calculated from the above-mentioned [rate of change in interplanar spacing of crystal lattice planes].
These results are shown in Table 5.
As shown in FIG. 4, the X-ray diffraction pattern of the brominated DPP is different from that of R254, but the peak position appears at the same place, so that the brominated DPP is the same as that of R254. The analysis was performed on the assumption that the crystal structure and the lattice plane of the crystal structure were taken.
As described above, the crystal structure of R254 has been analyzed by X-ray crystal structure analysis in the literature (Acta. Crystal. B49, 1056 (1993)), and the crystal structure is published in the CIF data format. By using this crystal structure CIF data, the Bragg angle (2θ) can be made to correspond to the lattice plane of the crystal structure by the calculation software Mercury.

The amount of Fe by ICP qualitative analysis was measured using iCAP6300Duo manufactured by Thermo Fisher Scientific. The measurement results are shown in Table 5.

The obtained pigment dispersion was diluted 50 to 200 times with PGMEA, treated with an ultrasonic homogenizer (Ultrasonic Cleaner US-105, manufactured by SND Co., Ltd.) for 5 minutes, and then the particle image was observed. .. This observation was performed using an S-5200 type electric field emission scanning electron microscope (manufactured by Hitachi High-Technologies Co., Ltd.) at an acceleration voltage of 20 kV at an observation magnification of 1 million times, and 100 particles that can be clearly identified from the observed image. The major axis was measured using SEM image analysis software (Scandium manufactured by OLYMPUS), and the average primary particle size, the standard deviation of the primary particle size, and the CV value of the primary particle size were calculated.
Table 5 shows these results and the viscosity of the pigment dispersion. Table 5 shows the number of coarse particles and the color evaluation results (contrast, brightness, film thickness, and heat resistance) that can be visually confirmed when the obtained cured film is observed with an optical microscope at a magnification of 500. The color evaluation values shown in Table 5 are adjusted so that the brightness is x = 0.6500 and y = 0.3230, and the contrast, film thickness, and heat resistance are adjusted to x = 0.6500. The measurement was performed on the cured film.

Among the measurement results shown in Table 5, the number of coarse particles (pieces) is 0 to 19: ○, 20 to 59: Δ, 60 or more: ×, and the contrast is 7000 or more: ○, 5000 to 6999: Δ, 4999 or less. : ×, brightness is 18.90 or more: ○, 18.80 to 18.89: Δ, 18.79 or less: ×, film thickness (μm) is 2.400 or less: ○, 2.401-2. It was determined that 600: Δ, 2.601 or more: ×, and the heat resistance (%) was 22.9 or less: ○, 23.0 or more: ×, and is shown in Table 5.

Regarding the above measurement results, if all the evaluations were ○, the overall evaluation was evaluated as ○.

In Examples 1 to 6 in which the crystallite size of the (1 1 1) plane is 140 Å or less and the crystallite size of the (1 5-1) plane is 80 Å or less, the crystallite size of the (1 1 1) plane is satisfied. The contrast and brightness were higher than those of Comparative Examples 1 to 3 in which the crystallite size exceeded 140 Å and the crystallite size of the (15-1) plane exceeded 80 Å. It is considered that this is because the area of the crystal grain boundaries is reduced by controlling the crystallite size to be small, and the light scattering is reduced, so that the contrast and brightness of the obtained color filter are improved. Further, it is considered that the primary particles are composed of small crystallites, so that the primary particles are small, the transmittance of the color filter is high, the light scattering is suppressed low, and the contrast and the brightness are improved.
Examples 1 to 6 have a crystallite size ratio of the (1 1 1) plane to the (020) plane in the range of 0.85 to 1.25 and an average primary particle size of 5 to 40 nm. The contrast and brightness were higher than those of Comparative Examples 1 to 3 having a ratio of crystallite sizes outside this range and an average primary particle size. This is because the average primary particle size is small and the aspect ratio of the crystallites is small, which makes it easier for the crystallites to be arranged with less anisotropy in the primary particles, and the primary particles become optically uniform, resulting in contrast and brightness. I think that has improved. In addition, it is considered that the primary particles composed of crystallites that are close to spheres also have a small aspect ratio, which makes it difficult to align in the cured film and reduces the anisotropy of the cured film, which also contributes to the improvement of contrast and brightness. .. Furthermore, since the aspect ratio of the primary particles is small, the specific surface area of the pigment fine particles formed from the primary particles is small, and the surface energy of the particles is small, so that aggregation of the particles can be suppressed, and the viscosity is high in the prior art. The brominated DPP pigment dispersion of the present invention can ensure dispersion stability even though it is a fine pigment that may cause thickening and gelation with time.
In Examples 1 to 6, where the rate of change of the (020) plane of the crystal lattice at 80 ° C. and 230 ° C. is 3.0% or less, the rate of change of the plane spacing exceeds 3.0%. The result was that the heat resistance was higher than that of Examples 1 to 3. From this, since the brominated DPP having a small rate of change in the interplanar spacing due to heating shown in the examples has a specific crystallite size or a specific crystallite size ratio, the crystal grain boundaries in the crystal structure are suppressed to be small. It is considered that the crystal structure has a stable crystal structure in which crystallites are densely assembled, and the decrease in contrast due to heating can be alleviated.
From the above, it can be seen that by controlling various physical properties of brominated DPP, it is possible to obtain brominated DPP pigment fine particles that satisfy the characteristics required for a color filter such as contrast, brightness, and heat resistance at a high level.

Example 7
Pigment micronization (preparation of pigment solution)
As the solvent used as the base material in Table 6, DMSO of raw material 1 was 65.5 wt% and BTMA soln of raw material 2 was used. 22.5 wt% and 12 wt% of a commercially available pigment base material 3 (the one having a primary particle size of 100 to 120 nm as observed by STEM) were added, and the mixture was stirred with Clairemix to dissolve R254. .. The formulation and preparation conditions are shown in Table 6 together with other examples and comparative examples.

(Preparation of poor solvent)
As a poor solvent, 20 wt% of acetic acid of raw material 2 and 40 wt% of MeOH of raw material 3 were added to 40 wt% of tap water of raw material 1 in Table 7, and mixed using Clairemix to prepare a poor solvent. The preparation conditions are shown in Table 7 together with other examples and comparative examples.

(Precipitation of pigment fine particles)
A reaction device is used that uniformly diffuses, stirs, and mixes in a thin film fluid formed between the processing surfaces 1 and 2 which are arranged facing each other and can be approached and separated from each other and at least one of them rotates with respect to the other. Then, the prepared pigment solution and the poor solvent were mixed, and the precipitation reaction was continuously carried out in the thin film fluid. Specifically, a poor solvent is sent as the first fluid from the center of the apparatus shown in FIG. 1 (first introduction unit d1), and the pigment solution is used as the second fluid from the second introduction unit d2 for processing surface 1, Introduced between two. The first fluid and the second fluid were mixed in the thin film fluid to precipitate the pigment fine particles dissolved in the pigment solution, and the pigment fine particle dispersion was discharged from the treatment surfaces 1 and 2. The supply pressure of the first fluid and the second fluid, the flow rate of the liquid to be fed, the liquid feed temperature, the rotation speed of the processing unit 10 (hereinafter referred to as the rotation speed), the back pressure, and the temperature of the discharge liquid are used as the conditions for producing the pigment fine particles. It is shown in Table 8 together with other examples and comparative examples. The liquid feeding temperatures of the first fluid and the second fluid are measured immediately before the introduction of the device (more specifically, immediately before the introduction between the treatment surfaces 1 and 2) of the temperatures of the first fluid and the second fluid, respectively. The temperature of the discharged liquid is a measurement of the temperature of the pigment fine particle dispersion liquid immediately after being discharged from the treatment surfaces 1 and 2. Further, as the opening d20 of the second introduction portion d2, as shown by the dotted line in FIG. 2B, a concentric annular shape surrounding the central opening of the processing surface 2 was used.

(Washing / drying)
(A) In order to separate only the pigment fine particles from the pigment fine particle dispersion liquid discharged from the treatment surfaces 1 and 2, the pigment fine particles are loosely aggregated and filtered under reduced pressure (-0.1 MPaG) using a filter paper. Pigment fine particles were collected by filtration.

(B) The obtained wet cake of pigment fine particles is put into 5 L of tap water, stirred and washed with Clairemix at 6000 rpm for 1.5 minutes, and the washed liquid is recovered by vacuum filtration again. The operation was repeated 4 times to obtain a wet cake of pigment fine particles. The obtained wet cake of the pigment fine particles was vacuum-dried to obtain a dry powder of the pigment fine particles. Vacuum drying was performed at 30 ° C. and −0.10 MPaG for 72 hours.
The obtained dry powder of the pigment fine particles was subjected to X-ray diffraction measurement with a multipurpose X-ray diffractometer X'Pert Powerer (manufactured by PANalytical Co., Ltd.), and data analysis software HighScorePlus Ver. Analysis was performed using 3.0e (3.0.5) (manufactured by PANalytical). Further, ICP quantitative analysis was performed to measure the amount of Fe contained in the pigment fine particles.

Preparation of Pigment Dispersion 10 parts by weight of the dry powder of the obtained pigment fine particles, 5 parts by weight of "BYKLPN6919" (manufactured by Big Chemie) as a dispersant, and C.I. I. 1 part by weight of the sulfonated derivative of Pigment Red 254 and 70 parts by weight of propylene glycol monomethyl ether acetate (hereinafter, "PGMEA") as a solvent were stirred and mixed with a paint shaker (manufactured by Asada Iron Works Co., Ltd.) and dispersed for 6 hours to disperse R254. Pigment dispersion was obtained. Further, the obtained pigment dispersion was diluted with PGMEA to obtain a dispersion for STEM observation. The obtained dispersion liquid for STEM observation was dropped onto the grid, and STEM observation was performed.
Further, in order to adjust the chromaticity, a pigment dispersion of R177 was prepared by the same preparation method as described above.

Preparation of Photosensitive Coloring Composition With respect to the pigment dispersion of R254 and the pigment dispersion of R177, each photosensitive coloring composition was prepared by the following production methods.
50 parts by weight of pigment dispersion, 6 parts by weight of acrylic resin ("ZAH-110" manufactured by Soken Kagaku Co., Ltd.), 4 parts by weight of dipentaerythritol hexaacrylate as a polymerizable monomer, 2-methyl-1- as a photopolymerization initiator (4-Methylthiophenyl) -2-morpholinopropane-1-one (BASF "IRGACURE 907") 1 part by weight and 100 parts by weight of PGMEA as a solvent are stirred and mixed so as to be uniform, and then a 1.0 μm filter is used. To obtain a photosensitive coloring composition.

Preparation of cured film The cured film was prepared for the following two types.
Using the photosensitive coloring composition of R254, a cured film having a chromaticity adjusted so that the chromaticity x = 0.6500 during the post-baking process was prepared, and the coarse particles, contrast, film thickness and heat resistance were evaluated. went.
Using the photosensitive coloring compositions of R254 and R177, a cured film whose chromaticity was adjusted so that the chromaticity was x = 0.6500 and y = 0.3230 during the post-baking step was prepared, and the brightness was evaluated. It was.

1. 1. Pre-baking step The photosensitive coloring composition obtained above was applied onto a glass substrate with a spin coater and then dried at 80 ° C. for 3 minutes to obtain a coating film. A photomask was placed on the obtained coating film, and 100 mJ / cm ² of ultraviolet rays were irradiated using an ultraviolet fiber spot irradiation device. Further, the mixture was vibrated in an alkaline aqueous solution (0.04 wt% potassium hydroxide aqueous solution) and then rinsed with pure water to remove the uncured portion. The rotation speed of the spin coater was changed so as to sandwich the specified chromaticity to prepare three coating films, and the evaluation items of the specified chromaticity could be calculated by the first-order correlation method.

2. Post-baking step The coating film from which the uncured portion was removed was preheated in a dryer at 80 ° C. for 30 minutes, and then main heat treated at 230 ° C. for 30 minutes to obtain a cured film.

Example 8
A cured film was obtained in the same manner as in Example 7 except that the formulation of the pigment solution shown in Table 6, the formulation of the poor solvent shown in Table 7, and the conditions for producing pigment fine particles shown in Table 8 were changed.

Example 9
A cured film was obtained in the same manner as in Example 8 except that the formulation of the pigment solution shown in Table 6 and the conditions for producing pigment fine particles shown in Table 8 were changed.

Comparative Example 4
As a comparative example in which the pigment was not micronized, R254 used as the pigment base material in Examples 7 to 9 was prepared as a pigment dispersion by the same method as in Example 7 without pigment micronization. A cured film was obtained in the same manner.

Comparative Example 5
A cured film was obtained in the same manner as in Example 9 except that the formulation of the poor solvent shown in Table 7 and the conditions for producing pigment fine particles shown in Table 8 were changed. Since only tap water was used as the poor solvent, the poor solvent was not prepared using Clairemix.

Comparative Example 6
350 mL of the pigment solution prepared in Example 8 using a burette was added to 35 mL / min in 1.1 L of the poor solvent prepared in Example 8 stirred at 1700 rpm using Claremix. The pigment fine particle dispersion was obtained at the same rate as above. In order to separate only the pigment fine particles from the pigment fine particle dispersion, the pigment fine particles are loosely aggregated, and the pigment fine particles are collected by filtration under reduced pressure (-0.1 MPaG) using a filter paper, and the collected pigment fine particles are collected. Wet cake was washed and dried in the same manner as in Example 7. Then, a pigment dispersion was prepared by the same method as in Example 7, and a cured film was obtained in the same manner thereafter.

The evaluation method was the same as in Examples 1 to 6 and Comparative Examples 1 to 3, and the results are shown in Table 9. The determination was also made in the same manner as in Examples 1 to 6 and Comparative Examples 1 to 3.

In Examples 7 to 9 in which the crystallite size of the (1 1 1) plane is 140 Å or less and the crystallite size of the (1 5-1) plane is 80 Å or less, the crystallite size of the (1 1 1) plane is satisfied. The contrast and brightness were higher than those of Comparative Examples 4 to 6 in which the crystallite size exceeded 140 Å and the crystallite size of the (15-1) plane exceeded 80 Å. It is considered that this is because the area of the crystal grain boundaries is reduced by controlling the crystallite size to be small, and the light scattering is reduced, so that the contrast and brightness of the obtained color filter are improved. Further, it is considered that the primary particles are composed of small crystallites, so that the primary particles are small, the transmittance of the color filter is high, the light scattering is suppressed low, and the contrast and the brightness are improved.
Examples 7 to 9 have a crystallite size ratio of the (1 1 1) plane to the (020) plane in the range of 0.85 to 1.25 and an average primary particle size of 5 to 40 nm. The contrast and brightness were higher than those of Comparative Examples 4 to 6 having a ratio of crystallite sizes outside this range and an average primary particle size. This is because the average primary particle size is small and the aspect ratio of the crystallites is small, which makes it easier for the crystallites to be arranged with less anisotropy in the primary particles, and the primary particles become optically uniform, resulting in contrast and brightness. I think that has improved. In addition, it is considered that the primary particles composed of crystallites that are close to spheres also have a small aspect ratio, which makes it difficult to align in the cured film and reduces the anisotropy of the cured film, which also contributes to the improvement of contrast and brightness. .. Furthermore, since the aspect ratio of the primary particles is small, the specific surface area of the pigment fine particles formed from the primary particles is small, and the surface energy of the particles is small, so that aggregation of the particles can be suppressed. The R254 pigment dispersion of the present invention can ensure dispersion stability even though it is a fine pigment that may cause thickening and gelation with time.
In Examples 7 to 9, where the rate of change of the (020) plane of the crystal lattice at 80 ° C. and 230 ° C. is 3.0% or less, the rate of change of the plane spacing exceeds 3.0%. The result was that the heat resistance was higher than in Examples 5 and 6. From this, since R254, which has a small rate of change in the interplanar spacing due to heating shown in the examples, has a specific crystallite size or a specific crystallite size ratio, the crystal grain boundaries in the crystal structure are suppressed to be small, and the crystals are crystallized. It has a stable crystal structure in which the children are densely assembled, and it is considered that the decrease in contrast due to heating can be alleviated.
From the above, it can be seen that by controlling various physical properties of the diketopyrrolopyrrole pigment fine particles, it is possible to obtain red pigment fine particles that satisfy the characteristics required for the color filter such as contrast, brightness, and heat resistance at a high level. ..

Claims (19)

Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å or less. , Diketopyrrolopyrrole pigment fine particles containing 90% or more of the compound represented by the following general formula (I).

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å or less. , The crystallite size in the plane direction (15-1) calculated by the X-ray diffraction pattern is 80 Å or less, and the diketopyrrolopyrrole pigment fine particles containing the compound represented by the following general formula (I).

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] Of the eight crystal lattice planes calculated by the X-ray diffraction pattern (± 1 ± 1 ± 1), the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is calculated by the X-ray diffraction pattern. Of the crystal lattice planes formed, the ratio of crystallite sizes calculated by dividing by the crystallite size in the plane direction corresponding to the maximum peak at 2θ = 3 to 1.25 ° is 0.85 to 1.25. A diketopyrrolopyrrole pigment fine crystal containing a compound represented by the following general formula (I), which has an average primary particle size of 5 to 40 nm.

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and contains 90% or more of the compound represented by the following general formula (I). Diketopyrrolopyrrole pigment fine particles.

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 140 Å or less, and 2θ = 28.0 ° ± calculated by the X-ray diffraction pattern. Diketopyrrolopyrrole pigment fine particles containing 90% or more of the compound represented by the following general formula (I), wherein the crystallite size of the crystal lattice plane corresponding to 0.3 ° is 80 Å or less.

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] The diketopyrrolopyrrole pigment fine particles according to claim 1, 2, 4 or 5, wherein the average primary particle size is 5 to 40 nm. The crystallite size of the crystal lattice plane corresponding to 2θ = 24.5 ° ± 0.3 ° calculated by the X-ray diffraction pattern is 2θ = 7.4 ° ± 0.3 ° calculated by the X-ray diffraction pattern. The ratio of the crystallite size calculated by dividing by the crystallite size of the crystal lattice plane corresponding to is 0.85 to 1.25, and the average primary particle size is 5 to 40 nm. Diketopyrrolopyrrole pigment fine particles containing a compound represented by the following general formula (I).

[In the above general formula (I), X ₁ and X ₂ may independently have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent. Indicates a saturated or unsaturated alkyl group or an aryl group which may have a substituent. ] The diketopyrrolopyrrole pigment fine particles according to any one of claims 2, 3 and 7, which contain 90% or more of the compound represented by the general formula (I). The diketopyrrolopyrrole pigment fine particles according to any one of claims 1 to 8 , wherein the standard deviation of the primary particle size is less than 7.0. The diketopyrrolopyrrole pigment fine particles according to any one of claims 1 to 9 , wherein the coefficient of variation (CV value) of the primary particle size is less than 30. The diketopyrrolopyrrole pigment fine particles according to any one of claims 1 to 10 , wherein the Fe content is 35 ppm or less. The diketopyrrolopyrrole pigment fine particles according to any one of claims 1 to 11 , wherein the general formula (I) is represented by the following general formula (II).

[In the above general formula (II), R may have a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, -CF ₃ , and a substituent independently of each other. Indicates an alkyl group or an aryl group which may have a substituent. ] The diketopyrrolopyrrole pigment fine particles according to claim 12 , wherein R is bromine and is represented by the following formula (III).

Of the eight (± 1 ± 1 ± 1) crystal lattice planes calculated by the X-ray diffraction pattern, the crystallite size in the plane direction corresponding to the maximum peak in the X-ray diffraction pattern is 140 Å or less. , Diketopyrrolopyrrole pigment fine particles containing a compound represented by the following formula (III).

The diketopyrrolopyrrole pigment fine particles according to claim 14, which contain 90% or more of the compound represented by the above formula (III). A pigment dispersion containing at least an organic pigment and an organic solvent, wherein the organic pigment is the diketopyrrolopyrrole pigment fine particles according to any one of claims 1 to 15. .. A photosensitive coloring composition containing at least the pigment fine particles according to any one of claims 1 to 15. A color filter containing at least the photosensitive coloring composition according to claim 17. A color filter containing at least the pigment fine particles according to any one of claims 1 to 15.

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