JP5666037B1 - Method for producing pigment dispersion, pigment dispersion and colored resin composition for color filter - Google Patents

Abstract

Provided is a pigment dispersion that has excellent dispersibility and dispersion stability, and also exhibits excellent optical performance when used as a display material such as a liquid crystal display material and an organic EL display material. . A method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent, wherein (A) the pigment has a main peak of an X-ray diffraction spectrum. A pigment dispersion characterized by containing (A) a pigment (a) having a value (S / N) representing the degree of crystallinity obtained by dividing the intensity (S) by the intensity (N) of background noise (S / N) is 90 or less. A liquid production method, a pigment dispersion produced by the production method, a photosensitive colored resin composition containing the pigment dispersion, and a color filter obtained using the photosensitive colored resin composition. [Selection] Figure 1

Description

  The present invention relates to a method for producing a pigment dispersion and a pigment dispersion that can be produced by the production method. More specifically, the invention includes a pigment (a) having an S / N of 90 or less and wet dispersion. The present invention relates to a method for producing a pigment dispersion.

  There is an increasing demand for high contrast, high brightness, high brightness, high color reproducibility, high dispersibility, dispersion stability, etc. in color displays, CCDs, color prints, and color paints. It is desired to improve the pigment dispersion.

Particularly in recent years, demand for liquid crystal displays and organic EL displays has increased due to the development of computer displays and the like. Accordingly, in the performance of these displays, high image quality such as improvement of contrast and color reproducibility is strongly desired.
In such a situation, there is a growing demand for higher contrast, higher brightness, improved color reproducibility, and the like even for color filters having a function of displaying a color display.

  In addition to display applications, for example, gravure inks, offset inks, flexo inks, screen inks, ink-jet inks, etc .; various paints; various resists, etc., pigment dispersions having excellent performance are desired. Yes.

  Here, for example, a color filter used in a display generally has a transparent substrate, a colored layer, a light-shielding portion, and the like. As a method for forming this colored layer, a pigment dispersion method, a dyeing method, an electrodeposition method, and the like. Methods, printing methods, and the like are known, and among them, the pigment dispersion method is widely used in terms of spectral characteristics, durability, pattern shape, accuracy, and the like (Patent Documents 1 and 2).

However, in general, a color filter in which a pigment is dispersed may cause the polarized light transmitted through the liquid crystal material to be canceled by the dispersed pigment, which causes a problem that the contrast between the ON state and the OFF state becomes low, parallel luminance There is a problem that the ratio of the luminance to the orthogonal luminance becomes small. Further, due to the reduction in power consumption of the backlight and the characteristics of the LED backlight, there are increasing demands for increasing the brightness and contrast of the color filter.
In the conventional dry pulverization method, it is difficult to reduce the particle size of the pigment to a uniform size, and a technique for improving the contrast by reducing the particle size of the pigment by the milling method has become mainstream.

As a method for producing a pigment, conventionally, for example, pigmentation by grinding is performed, and dry dispersion is often adopted as one of them. However, since this process alone is not sufficient for miniaturization, aggregation occurs, or pigment particles are not uniform, treatment with water and solvent, treatment with solvent, emulsion treatment with water, etc. Are often performed in combination.
The grinding method includes dry dispersion, solvent milling, dry salt milling, solvent salt milling, and the like. In particular, in the case of pigments used for color filters and pigments used for inkjet inks, solvent salt milling is often employed because it is required to have a high degree of miniaturization and crystal particles.

  On the other hand, in order to improve the dispersibility and dispersion stability of pigments, various dispersants and pigment modifiers have been studied. For example, Patent Document 3 discloses a grafted oligomer as a dispersant. Patent Document 4 describes a pigment derivative having an acidic group.

  However, with regard to pigments used in fields that require a high degree of dispersion, particularly for color filters for displays, the above-described technology is not sufficient, in order to respond to demands for higher contrast, higher dispersion, etc. Further improvements were desired.

JP 2007-133131 A JP 2009-244617 A JP-A-10-339949 JP 2006-206737 A

  Although dry dispersion has been performed conventionally, it is not sufficient for miniaturization, aggregation occurs, or pigment particles are not uniform. What used only the process was not used, and there was no idea of using what S / N is 90 or less.

The present invention has been made in view of the above-described background art, and its problem is excellent dispersibility / dispersion stability, and further, display materials such as liquid crystal display materials and organic EL display materials, CCD materials, It is to provide a pigment dispersion that exhibits excellent optical performance and excellent pigment dispersion stability when used as an inkjet ink material, etc., and in particular, a pigment dispersion that provides a color filter that achieves high contrast Is to provide.
Another object of the present invention is to provide a colored resin composition, a photosensitive colored resin composition, a color filter, a liquid crystal display, an organic EL display, a CCD, and an inkjet ink using the pigment dispersion.

  As a result of intensive studies to achieve the above object, the inventor of the present invention contains a pigment (a) having an S / N of 90 or less, which will be described later, and disperses and disperses stably. In particular, the present invention has been completed by finding a method for producing a pigment dispersion having good contrast when used for a color filter.

That is, the present invention is a method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent,
(A) Pigment (a) having a value (S / N) of 90 or less obtained by dividing the intensity (S) of the main peak of the X-ray diffraction spectrum by the intensity (N) of the background noise as the (A) pigment It is intended to provide a method for producing a pigment dispersion characterized by being contained and wet-dispersed.

  Of the (A) pigments used in the present invention, the (A) pigment having an S / N of 90 or less may be referred to as “(A) pigment (a)”.

  The present invention also provides a pigment dispersion characterized by being produced by the method for producing a pigment dispersion described above.

  Moreover, this invention provides the colored resin composition for color filters characterized by containing said pigment dispersion liquid.

  Moreover, this invention provides a color filter characterized by being obtained using said colored resin composition for color filters.

  Moreover, this invention provides the display apparatus which has said color filter.

  According to the present invention, the above-mentioned problems and problems are solved, and in a color display, a color print, a color coated product, etc., a method for producing a pigment dispersion having excellent dispersibility and dispersion stability, and A novel pigment dispersion produced can be provided.

  The pigment used in the pigment dispersion of the present application has an S / N of 90 or less. A pigment having an S / N of 90 or less is considered to have a lower crystallinity than a pigment having an S / N of more than 90, and the fastness of the pigment is lowered, so that it can be more finely dispersed. . For example, when the final dispersion is a wet dispersion, for example, a very fine dispersion can be achieved.

Therefore, a color display, a color printed material, and a color coated material obtained using such a pigment dispersion have excellent optical performance.
In particular, color displays such as liquid crystal displays and organic EL displays obtained using such pigment dispersions have high contrast, high light transmittance, and high brightness. Specifically, the ratio of parallel luminance to orthogonal luminance is large, the degree of polarization cancellation is small, and the contrast between the ON state and the OFF state can be increased.

The pigment dispersion obtained by using the method for producing a pigment dispersion of the present invention exhibits excellent optical performance as described above when used as a display material such as a liquid crystal display material and an organic EL display material. Show.
In particular, a color filter for a liquid crystal display obtained by using the pigment dispersion of the present invention has a finely dispersed pigment and rarely cancels the polarization obtained by the liquid crystal substance. For example, a liquid crystal display having high contrast, high transmittance, and high luminance can be provided.

In order to explain the intensity (S) of the main peak of the X-ray diffraction spectrum and the intensity (N) of the background noise, an outline of the X-ray diffraction spectrum drawn after removing the background using the Sonnevert-Visser method. FIG.

  Hereinafter, the present invention will be described, but the present invention is not limited to the following specific embodiments, and can be arbitrarily modified within the scope of the technical idea.

1. The present invention is a method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent,
As the (A) pigment, (A) the pigment (a) having a value (S / N) of 90 or less obtained by dividing the intensity (S) of the main peak of the X-ray diffraction spectrum by the intensity (N) of the background noise It is a manufacturing method of the pigment dispersion liquid characterized by making it contain and wet-disperse.

1-1. (A) Pigment 1-1-1. S / N
The pigment (A) in the present invention has an S / N (hereinafter simply referred to as “S / N”) obtained by dividing the intensity (S) of the main peak of the X-ray diffraction spectrum by the intensity (N) of the background noise. May be abbreviated), but it is essential that it is 90 or less. S / N is positioned as a value representing the degree of crystallinity.

  The X-ray diffraction spectrum is a concentrated X-ray powder X-ray diffractometer using CuKα ray as an X-ray source, for example, “RINT-TTR III” manufactured by Rigaku Corporation. = 3-55 °, sampling width 0.02 °, scan speed 5 ° / min, diverging slit 1/4, scattering slit 1/4, and light receiving slit 0.45 mm.

  The intensity (S) of the main peak and the intensity (N) of the background noise are obtained after removing the background from the X-ray diffraction spectrum. The Sonnevelt-Visser method is used for background removal. At this time, the peak width threshold is 0.10, and the intensity threshold is 0.01.

Here, the “main peak of the X-ray diffraction spectrum” means the peak having the maximum diffraction peak among the diffraction peaks caused by the crystallinity of the pigment (A) contained in the pigment dispersion of the present invention. In other words, the “main peak intensity (S)” refers to the height of the main peak of the X-ray diffraction spectrum.
The “background noise intensity (N)” is the average spectrum in the scanning range (for example, 2θ = 47.5 ° to 48.0 °) in which the peak of the X-ray diffraction spectrum derived from the pigment (A) is not detected. This refers to the intensity, which is the average background noise height obtained by the following method, which is not caused by the crystallinity of the pigment (A).

The calculation method and definition of “background noise intensity (N)” are shown below. The peak height derived from noise in the scanning range 2θ = 47.5 ° to 48.0 ° is inspected 26 times every 0.02 °, and out of the 26 points, a total of 12 points excluding 7 points each above and below Let the arithmetic mean value of “the background noise intensity (N)”.
When the peak of the X-ray diffraction spectrum derived from (A) pigment is detected in the scanning range 2θ = 47.5 ° to 48.0 °, 2θ = 45.0 ° to 55.0 ° The range is changed to a scanning range of 0.5 ° continuous with 2θ avoiding the peak, and 26 points are similarly detected.

  As described above, the intensity (S) of the main peak and the intensity (N) of the background noise are obtained after removing the background from the X-ray diffraction spectrum. Here, “background” refers to the crystallinity. It refers to an added portion caused by Compton scattering or the like, not the resulting diffraction peak or the base (tailing portion) of the diffraction peak. FIG. 1 is an X-ray diffraction spectrum chart with the background removed by the method described above.

The numerical value (concept) of “S / N” is a raw material of the pigment dispersion liquid, where the intensity (S) of the main peak may vary depending on the measurement conditions. A numerical value (concept) “S / N” is introduced so as to have a value unique to “(A) pigment as“ thing ””.
Further, in the present invention, the main peak itself and the intensity (S) of the main peak are defined as those obtained by preparing a measurement sample by the method described in the examples, and the S / N measured as such.

  The upper limit of S / N is essential to be 90 or less, but is preferably less than 90, more preferably 70 or less, particularly preferably 60 or less, and 50 or less. Is more preferable, and most preferably 30 or less.

  The preferred value of the upper limit depends on the type of the pigment (A), but if the upper limit is less than or equal to the above, the fastness of the pigment (A) is low because of low crystallinity, that is, pulverization, dispersion, etc. are easy. Fine dispersion by dispersion when preparing a pigment dispersion is facilitated. Also, the dispersion time can be shortened. When the upper limit of S / N is set to the above by dry dispersion, it is particularly preferable in that fine dispersion is possible.

  In particular, when preparing a pigment dispersion by wet-dispersing the pigment, it is preferable in that fine dispersion can be easily performed. As a result, color displays, color prints, and color coated products obtained using the pigment dispersion have not only excellent dispersibility, but color displays such as liquid crystal displays and organic EL displays have high contrast. The light transmittance is high and the display becomes high brightness.

Here, “brightness” and “contrast” are measured by the method described in the examples and are defined as those measured, and “contrast” is shown below.
[Contrast] = [Parallel luminance (cd / m ² )] / [Orthogonal luminance (cd / m ² )]

The lower limit of S / N is not particularly limited and is preferably as small as possible. However, it is preferably 1.4 or more, more preferably 1.6 or more, and particularly preferably 1.8 or more.
If the lower limit is less than or equal to the above, the production cost will increase, and with respect to the physical properties such as dispersibility, dispersion stability, contrast, transmittance, and luminance, the physical property improvement corresponding to the increase in production cost with the lower limit being not more than the above cannot be obtained. In some cases, no further improvement is expected.

  As a result of investigation by the present inventor, (A) when a pigment is dispersed to produce a pigment dispersion, (B) the particle size of the pigment added together with the dispersant and (C) the solvent, and the above pigment dispersion In some cases, there was no correlation between the performance of the liquid or the color display obtained using the pigment dispersion, the color printed material, and the color coated material.

In producing the pigment dispersion, (A) the pigment is subjected to a dispersion treatment, and the particle size and crystallinity of the pigment particles after the dispersion treatment are changed by the dispersion treatment. In general, in the case of wet dispersion, the dispersed particle size is reduced, and the crystallinity is improved, that is, the peak intensity of X-ray diffraction is increased.
Comparing that the S / N is set to 90 or less at the stage of the (A) pigment as the raw material and that the S / N is not set to 90 or less at the stage of the (A) pigment as the raw material, When / N is 90 or less, the average dispersed particle diameter of the pigment in the pigment dispersion after the final dispersion treatment can be reduced. Therefore, regarding the physical properties of the color filter such as contrast, transmittance, and luminance, it is possible to obtain an excellent one when the S / N is set to 90 or less at the stage of the (A) pigment as a raw material.

  If both can be finely dispersed until the average dispersed particle size becomes the same, the average dispersed particle size is reached when the S / N is 90 or less at the stage of the pigment (A) as a raw material. The time to do this can be greatly reduced. In addition, a pigment dispersion having excellent dispersibility and dispersion stability, which is the effect of the invention of the present application, is obtained, and the use (utilization) field of the pigment dispersion obtained at that time (for example, a photosensitive colored resin composition, In color filters, ink-jet inks, etc.), brightness and contrast are improved. On the other hand, with regard to fastness, for example, chemical resistance and light resistance, when the average dispersed particle size is the same, there is almost no difference in performance.

The “(A) pigment (a) having an S / N of 90 or less” in the present invention is a step immediately before the dispersion treatment in which the wet dispersion treatment is performed and the pigment dispersion is contained in the pigment dispersion production method. It is.
The present invention is a method for producing a pigment dispersion in which (A) a pigment is contained by dispersing together with at least (B) a dispersant and (C) a solvent, and the S / N is 90 or less (A It is also a method for producing a pigment dispersion characterized in that the pigment (a) is wet-dispersed and contained in the pigment dispersion.

1-1-2. Types of Pigment The (A) pigment in the present invention is not particularly limited as long as it is a colored solid and dispersible including achromatic colors such as white, black, and gray, but is a so-called colored pigment. Is preferred.
The substance that forms the pigment (A) is not particularly limited as long as it satisfies the above requirements as the pigment (A), but is preferably a color pigment used in displays, printed materials, paints, and the like. The color pigment used is particularly preferred.

Here, the colored pigment also includes achromatic pigments such as white, black, and gray. Specifically, blue pigments, green pigments, red pigments, yellow pigments, purple pigments, orange pigments, brown pigments, black pigments. Various color pigments such as pigments can be used.
Considering the case where the pigment dispersion of the present invention is used as a color filter material, among them, blue pigments, green pigments, red pigments, yellow pigments, purple pigments, etc. are generally low in contrast or high in contrast. Is preferably used in the present invention in view of the fact that it is required.

  Hereinafter, specific examples of pigments (A) as pigment-forming substances are shown by pigment numbers. The following “CI” means a color index.

Examples of red pigments include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 37, 38, 41, 47, 48, 48: 1, 48: 2, 48: 3, 48: 4, 49, 49: 1, 49: 2, 50: 1, 52: 1, 52: 2, 53, 53: 1, 53: 2, 53: 3, 57, 57: 1, 57: 2, 58: 4, 60, 63, 63: 1, 63: 2, 64, 64: 1, 68, 69, 81, 81: 1, 81: 2, 81: 3, 81: 4, 83, 88, 90: 1, 101, 101: 1, 104, 108, 108: 1, 109, 112, 113, 114, 122, 123, 144, 146, 147, 149, 151, 166, 168, 169, 170, 172, 173, 174, 175, 176, 177, 178, 17 , 181, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 216, 220, 221, 224, 230, 231, 232, 233, 235 236, 237, 238, 239, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 263, 264, 265, 266, 267 268, 269, 270, 271, 272, 273, 274, 275, 276 and the like.
Of these, C.I. I. Pigment Red 48: 1, 122, 168, 177, 202, 206, 207, 209, 224, 242, 254 and the like. I. Pigment red 177, 209, 224, 254 and the like.

Examples of blue pigments include C.I. I. Pigment Blue 1, 1: 2, 9, 14, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17, 19, 25, 27, 28, 29, 33, 35, 36, 56, 56: 1, 60, 61, 61: 1, 62, 63, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, 79 and the like.
Of these, C.I. I. Pigment blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, and the like. I. Pigment blue 15: 6.

Examples of green pigments include C.I. I. Pigment green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55, 58 and the like.
Of these, C.I. I. Pigment Green 7, 36, 58 and the like.

Examples of yellow pigments include C.I. I. Pigment Yellow 1, 1: 1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 41, 42, 43, 48, 53, 55, 61, 62, 62: 1, 63, 65, 73, 74, 75, 81, 83, 87, 93, 94, 95, 97, 100, 101, 104, 105, 108, 109, 110, 111, 116, 117, 119, 120, 126, 127, 127: 1, 128, 129, 133, 134, 136, 138, 139, 142, 147, 148, 150, 151, 153, 154, 155, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 172, 17 174, 175, 176, 180, 181, 182, 183, 184, 185, 188, 189, 190, 191, 191: 1, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202 , 203, 204, 205, 206, 207, 208, 213 and the like.
Of these, C.I. I. Pigment yellow 83, 117, 129, 138, 139, 150, 154, 155, 180, 185, 213, and the like. I. Pigment yellow 83, 138, 139, 150, 180, 213 and the like.

Examples of orange pigments include C.I. I. Pigment Orange 1, 2, 5, 13, 16, 17, 19, 20, 21, 22, 23, 24, 34, 36, 38, 39, 43, 46, 48, 49, 61, 62, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79 and the like.
Of these, C.I. I. Pigment oranges 38 and 71, and the like.

Examples of purple pigments include C.I. I. Pigment Violet 1, 1: 1, 2, 2: 2, 3, 3: 1, 3: 3, 5, 5: 1, 14, 15, 16, 19, 23, 25, 27, 29, 31, 32, 37, 39, 42, 44, 47, 49, 50 and the like.
Of these, C.I. I. Pigment violet 19, 23, and the like. I. And CI Pigment Violet 23.

In the present invention, one kind of the above pigment may be used, or two or more kinds thereof may be used.
Moreover, when the pigment dispersion liquid of this invention is a pigment dispersion liquid for the black matrix of a color filter, as a substance which forms (A) pigment, a black pigment can be used. The achromatic pigment (A) such as black may be the achromatic pigment alone or may be a mixture with pigments such as red, green and blue.

  From the viewpoint of chemical structure, the preferred pigment (A) in the present invention is an anthraquinone pigment such as Pigment Red 177; a quinophthalone pigment such as Pigment Yellow 138; an azo such as an azomethine pigment such as Pigment Yellow 150; Benzimidazolone pigments such as pigment yellow 180; quinoxaline pigments such as pigment yellow 213; phthalocyanine pigments such as pigment blue 15: 6; dioxazine pigments such as pigment violet 23; diketopyrrolopyrrole pigments; Examples thereof include quinacridone pigments; isoindoline pigments; isoindolinone pigments; indanthrene pigments and perylene pigments.

In the present invention, pigments having the same chemical structure, that is, the same system may be used alone or in combination of two or more. Moreover, you may use 2 or more types across systems.
The pigment having the above-described chemical structure is particularly easy to achieve the above-described effect when produced by the production method of the present invention, and in particular, Pigment Red 177, Pigment Yellow 150, Pigment Yellow 180, Pigment Yellow 213, Pigment Blue 15: 6 Pigment Violet 23. In particular, Pigment Red 177, Pigment Yellow 150, Pigment Blue 15: 6, Pigment Violet 23, and the like are most preferable in terms of increasing the contrast of the color filter, increasing the brightness, and improving the color reproducibility.

1-1-3. Acid Dye Derivative The pigment (A) in the present invention preferably contains an acid dye derivative because the effects of the present invention are easily obtained. In particular, it can be finely dispersed and is preferable for providing a display with high contrast, high dispersion stability, high light transmittance, and / or high brightness when used for a color filter.
“Acid dye derivative” means a dye derivative having an acidic group in its chemical structure, preferably a phthalocyanine pigment, a quinacridone pigment, a quinophthalone pigment, an azo pigment, an anthraquinone pigment, a diketopyrrolopyrrole type It is a dye derivative having at least one pigment skeleton selected from the group consisting of a pigment, a dioxazine-based pigment, and an isoindoline-based, and having an acidic group.
The acidic group of the pigment derivative is preferably at least one selected from the group consisting of a sulfo group, a sulfonamide group, a carboxyl group, and a metal salt or ammonium salt of the functional group.

The average amount of acidic groups introduced per molecule of pigment is not particularly limited, but is preferably 0.5 to 5. 0.6 to 4 is more preferable, and 0.7 to 3.5 is particularly preferable.
By introducing acidic groups, fine dispersion can be achieved, and when used for color filters in particular, a display having high contrast, high dispersion stability, high light transmittance, and / or high brightness is provided. Preferred for such reasons.

The (A) pigment in the present invention preferably contains a pigment and an acidic dye derivative. The acidic dye derivative interacts with the pigment and, when producing the pigment particle, adsorbs to or is incorporated into the pigment surface to define the particle size, crystallinity, etc. of the pigment particle or (A) pigment. To do.
Further, the acidic pigment derivative that interacts with the basic dispersant is adsorbed on the pigment surface, whereby the basic dispersant can be efficiently positioned on the pigment surface. As a result, when “processing to reduce S / N to 90 or less” such as dry dispersion processing described later, the obtained “(A) pigment (a) having an S / N of 90 or less” Fine dispersion and dispersion stabilization are possible, and high contrast can be achieved particularly when used for color filters.

The content of the acidic dye derivative in the entire pigment (A) in the present invention is not particularly limited, but is preferably 0.5 to 30 parts by mass, and 1 to 15 parts by mass with respect to 100 parts by mass of the pigment. More preferably, it is 2 to 10 parts by mass.
By setting it to the above lower limit or higher, stable dispersion and fine dispersion can be achieved at the time of wet dispersion, and by setting it to the upper limit or lower, it is possible to prevent a decrease in color value due to excess of the acidic dye derivative.

  In the present invention, as the (A) pigment, one or more of the above acidic dye derivatives may be used, and one or more of the above acidic dye derivatives are used for one kind of pigment. May be.

The acidic dye derivative may be added to the pigment particle dispersion at any stage. However, in consideration of adsorbing or incorporating the acidic dye derivative on the pigment surface, a process for producing a pigment. In the step of synthesizing the pigment, in the step of solvent salt milling the pigment with a kneader, in the step of subsequent treatment, in the step of dry pulverizing the pigment with an attritor, etc. Thereafter, it can be added during the process.
It can also be added to a good solvent or a poor solvent in the reprecipitation method, and can also be added after concentration or redispersion after precipitation of pigment particles.
That is, the acidic dye derivative may be contained in the pigment (A) before the dry dispersion treatment, may be blended when the acidic dye derivative is dry-dispersed, and the acidic dye derivative is wet-dispersed. You may mix | blend.

1-1-4. Preparation of Pigment (a) with S / N of 90 or Less There are no particular limitations on the preparation method of (A) Pigment (a) with S / N of 90 or less, and the synthesized pigment has a S / N of at that time. When it is 90 or less, it can be used as it is.
In addition, if the pigment particle after adsorbing or incorporating a pigment derivative such as an acidic pigment derivative on the pigment surface has an S / N of 90 or less at that time, it can be used as it is. .

Further, by applying a treatment such as dispersion to the pigment or pigment particle, the S / N can be set to 90 or less and used.
In the first place, it is difficult to obtain “pigment (a)” or “pigment particles containing a dye derivative” having an S / N of 90 or less (mostly does not exist), so that some processing is applied to make the S / N 90 or less. It is preferable.
Such “treatment” is not particularly limited, but is preferably a physical treatment such as dispersion treatment, pulverization, and dispersion treatment while being pulverized.
Although there is no particular limitation on the method of “dispersion treatment”, dry dispersion treatment is preferable because it is easy to reduce the S / N to 90 or less. As a result, fine dispersion can be achieved when producing a pigment dispersion. In particular, when used for a color filter, it is preferable because high contrast can be achieved.

Here, “dry dispersion treatment” refers to treatment for dispersion without using a liquid dispersion medium, or treatment for adding and dispersing a small amount of liquid dispersion medium.
For example, pigments such as Pigment Blue 15: 6 and Pigment Red 254 may undergo a crystal transition when dispersed without using any liquid dispersion medium, and Pigment Blue 15: 6 may undergo a crystal transition to α-type. Crystal transition can be prevented by adding and dispersing an organic solvent. The state of the dispersion at this time is a dry state. In such a case, it is defined as “dry dispersion treatment” in the present invention. Solvent salt milling is not defined in the category of “dry dispersion treatment”.
The amount of the liquid when the liquid is added and subjected to the dry dispersion treatment is more than 0 parts by mass, preferably 150 parts by mass or less, more preferably 100 parts by mass or less, and more preferably 50 parts by mass or less with respect to 100 parts by mass of the pigment. Particularly preferred is 30 parts by mass or less, and most preferred is 10 parts by mass or less.

In the present invention, as described above, “wet dispersion treatment” refers to the above-mentioned “(A) pigment (a) having an S / N of 90 or less” in the presence of (B) a dispersing agent (C) solvent. In the present invention, “wet dispersion treatment” uses “(C) solvent” which is the final solvent of the pigment dispersion of the present invention.
On the other hand, the “dry dispersion treatment” of the present invention is a treatment for dispersing using a smaller amount of liquid dispersion medium than the above “wet dispersion treatment”, and is performed by adding a liquid in order to suppress changes such as crystal transition. And is not a final dispersion treatment but a pretreatment for finally producing the pigment dispersion of the present invention, and the liquid added thereto is a pigment dispersion of the present invention. It is not limited to the (C) solvent which is the last solvent of a liquid.

As described above, the liquid dispersion medium may be contained within a range having no influence, but it is preferable that the liquid dispersion medium is not contained depending on the kind of the pigment.
Further, the “dry dispersion treatment” in the present invention includes a treatment such as dispersion or pulverization in which a mechanical treatment is applied without using a solid dispersion medium. Further, the “dry dispersion treatment” includes a treatment in which the particle size of secondary particles and the like is increased by the treatment. “Dry dispersion treatment” in the present invention includes treatment using a so-called dry dispersion apparatus or dry pulverization apparatus.

The specific method of the above “dry dispersion treatment” is not particularly limited, but is a media mill using beads, balls, sand or the like; a jet mill such as a jet mizer or counter jet mill; a roll mill; a cutter mill; a rod mill; A method using a mill such as planetary mill; erotic fall mill; tube mill; tower mill;
Among them, media mills such as bead mill, ball mill, sand mill, etc .; various jet mills; etc. are preferable. (A) It is suitable for the particle diameter of the pigment, and is particularly preferable because the S / N is easily set to 90 or less.

When a media mill is used for the dry dispersion treatment, the diameter of the media such as beads used for the dry dispersion treatment is not particularly limited as long as the S / N can be 90 or less, but is preferably 0.1 mm to 40 mm. 5 mm to 30 mm is more preferable, and 1 mm to 20 mm is particularly preferable. When the upper limit of the diameter of the medium is larger than the above value, the total surface area of the medium is decreased and the processing time is increased. When the lower limit is smaller than the above value, the processing energy by the medium is decreased and the processing time is increased.
Moreover, it is also preferable to disperse the media in different diameters in two or more stages. In that case, it is preferable to use a medium having a relatively large particle size for the first stage.

  In the present invention, the time of the dry dispersion treatment is not particularly limited, but is preferably 0.5 to 200 hours, more preferably 1 to 100 hours, so that the S / N of the (A) pigment is suitable. ˜60 hours is particularly preferred. When the upper limit of the dry dispersion treatment time is larger than the above value, energy consumption for the effect becomes large, and when the lower limit is smaller than the above value, a pigment having sufficiently low crystallinity cannot be obtained.

  Among the dry dispersion treatments, the S / N of the pigment (A) can be lowered particularly by using the above-mentioned apparatus (mill) and dry dispersion treatment conditions, resulting in a good pigment dispersion and high contrast. .

It is preferable to perform “dry dispersion treatment” to make the S / N 90 or less, more preferably 70 or less, particularly preferably 60 or less, further preferably 50 or less, Most preferably, it is 30 or less.
The preferred value of the upper limit depends on the type of the pigment (A), but if the upper limit is less than or equal to the above, the fastness of the pigment (A) is low because of low crystallinity, that is, pulverization, dispersion, etc. are easy. Fine dispersion by dispersion when preparing a pigment dispersion is facilitated. Also, the dispersion time can be shortened. When the upper limit of S / N is set to the above by dry dispersion, it is particularly preferable in that fine dispersion is possible.

The effect of reducing the S / N is as described above, and if the upper limit is less than or equal to the above, pulverization, dispersion, etc. are easily achieved, and fine dispersion is achieved in the “final dispersion step when preparing a pigment dispersion”. Or the dispersion time can be shortened.
In particular, when a pigment dispersion is prepared by performing a wet dispersion treatment or the like as the “final dispersion step when preparing a pigment dispersion”, it can be finely dispersed particularly easily. Color displays, color prints, and color coated products obtained by using not only have excellent dispersibility and dispersion stability, but also colors such as liquid crystal displays and organic EL displays obtained using the pigment dispersion. The display has a high contrast, a high light transmittance, and a high brightness display.

Further, when the S / N of the “pigment” or “pigment particle containing a pigment derivative” is larger than 90, the S / N is 90 or less (A) pigment (a Is preferred.
In the method for producing a pigment dispersion of the present invention, the value obtained by dividing the S / N of the (A) pigment after the dry dispersion treatment by the S / N of the (A) pigment before the dry dispersion treatment is 0.5. It is preferable to carry out a dry dispersion treatment so as to be as follows, more preferably a dry dispersion treatment so as to be 0.4 or less, and particularly preferably a dry dispersion treatment so as to be 0.3 or less. That is, it is preferable to lower the S / N and make the S / N 90 or less at the above ratio.
If it does in this way, the outstanding optical performance will be expressed, and also the dispersion time at the time of wet dispersion can be shortened significantly. Further, dispersibility can be improved.

Before and after the above-mentioned “treatment for reducing S / N to 90 or less”, the particle diameter of the pigment (A) may be increased or decreased. Even if the particle size of primary particles, secondary particles, and the like is increased by the “processing to reduce S / N to 90 or less” such as the dry dispersion processing described above, the S / N is even below a certain value. Then, the dispersibility in the manufacturing process of the pigment dispersion is improved, so that the above-described good result can be obtained.
The effect of reducing the crystallinity of the pigment is to promote fine dispersion during wet dispersion, so that the final pigment particle size becomes small.

1-1-5. The particle diameter of the pigment described later “The particle diameter of the pigment (A) used in the wet dispersion step in preparing the pigment dispersion is not particularly limited and may be large, but is preferably 30 nm to 500 nm, preferably 40 nm to 300 nm. Is more preferable, and 50 nm to 200 nm is particularly preferable.
If the particle size is too small, there is almost no correlation between the particle size and the final performance, so there is no need to make it so small, and workability may be deteriorated due to contamination by fine particles. On the other hand, if the particle size is too large, it may take too much time to reduce the S / N to 90 or less.

Specific measurement methods are described below. Although the definition is based on the following measurement method, actual measurement is not limited to this method. The particle diameter of the pigment (A) in the present invention represents “volume distribution median diameter (D50)”. (A) The pigment particle size is determined by attaching a dedicated bright field STEM sample stage and an optional detector to a field emission scanning electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation. It can be used as a microscope (hereinafter abbreviated as “STEM”), take a 200,000-fold STEM photograph, import it into the following software, select 100 pigments on the photograph, and select each diameter (passing length) ) And determined as a 50% cumulative particle size by volume from the volume-based distribution.
A measurement sample to be subjected to STEM is prepared by mixing a pigment and toluene and dropping the mixture on a collodion membrane-attached mesh. Further, when obtaining a volume-based particle size distribution or volume distribution median diameter (D50) from the STEM photograph, image analysis type particle size distribution measurement software “Mac-View Ver. 4” manufactured by Mountec Co., Ltd. is used.
Hereinafter, the particle diameter of the pigment (A) determined by the above measurement is referred to as “(A) TEM particle diameter of the pigment”.

1-2. (B) Dispersant 1-2-1. Polymer Dispersant and Low Molecular Dispersant The dispersant (B) in the present invention is not particularly limited, and known polymer dispersants and low molecular dispersants can be used for pigment dispersion.

  Examples of the polymeric dispersant include a random type dispersing agent made of a random (co) polymer; a block type dispersing agent made of a block copolymer; And) a graft type dispersant comprising a graft (co) polymer having repeating units bonded thereto, and the like.

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

  Among them, poly (meth) acrylate, sodium maleate-olefin copolymer, terminal carboxyl group-containing polyester (for example, Japanese Examined Patent Publication No. 54-34009); tetrakis (2-hydroxyalkyl) ethylenediamine is used as a starting material. Polyester having an acidic group and / or a basic group (JP-A-2-245231, etc.); a macromonomer (an oligomer having a polymerizable unsaturated group at one end), a monomer having a hydroxyl group, and a carboxy group-containing monomer are copolymerized A copolymer obtained by copolymerization of a macromonomer (an oligomer having a polymerizable unsaturated group at one end) and a monomer having a nitrogen atom (Japanese Patent Laid-Open No. Hei 8-259987). 10-339949 etc.) etc. are preferable.

Examples of the low molecular weight dispersant include an anionic compound having a sulfonic acid group, a carboxylic acid group, etc .; a cationic compound having a salt of an aliphatic amine, a quaternary ammonium salt, etc .; Ionic compounds; polymer compounds; and the like.
Specific examples include sorbitan fatty acid esters, polyoxyethylene alkylamines, alkyldiamines, alkanolamine derivatives (US Pat. No. 3,536,510), and the like.

Among the dispersants, a polymer dispersant is preferable, and among the polymer dispersants, a basic block type dispersant and / or a basic graft type dispersant is functionally separated from the pigment adsorption site and the solvent affinity site. It is preferable from the point of being.
When the “treatment for reducing S / N to 90 or less” such as the above-described dry dispersion treatment is performed, the obtained “(A) pigment (a) having an S / N of 90 or less” is then finely dispersed. In particular, when used for a color filter, high contrast can be achieved. Further, the basic block type dispersant and / or the basic graft type dispersant are preferable from the viewpoint of the temporal stability of the pigment dispersion.
Further, when used in combination with the above-described acidic dye derivative, the above-described effects of the present invention are easily exhibited synergistically.

  Here, “(B) the dispersant is a basic block type dispersant and / or a basic graft type dispersant” means that (B) the dispersant is a basic block type dispersant, A basic graft type dispersant, a combination of a basic block type dispersant and a basic graft type dispersant, a basic block type dispersant and a basic graft type dispersant at the same time. It means that there is. Further, the combined use of a dispersant that is neither a basic block type dispersant nor a basic graft type dispersant is excluded.

1-2-2. Basic Block Type Dispersant “Basic Block Type Dispersant” means a monomer having a basic group such as an amino group, monoalkylamino group, dialkylamino group; salts thereof; hereinafter abbreviated as “a monomer”. ) And another monomer different from the monomer (hereinafter abbreviated as “b monomer”), a binary copolymer may be used, and a ternary or higher copolymer may be used. It may be combined.

Examples of the a monomer include a quaternary ammonium base and / or a (meth) acrylate compound containing a secondary or tertiary amino group or a salt thereof in which hydrogen bonded to nitrogen may be substituted with a substituent. A tertiary amino group and / or a quaternary ammonium base is particularly preferable.
Specifically, dialkylaminoalkyl ester of (meth) acrylic acid, diarylaminoalkyl ester of (meth) acrylic acid, diaralkylaminoalkyl ester of (meth) acrylic acid, dialkenylaminoalkyl ester of (meth) acrylic acid And salts thereof.
Specifically, for example, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminoethyl (meth) acrylate, diethylaminopropyl (meth) acrylate, N-methylol (meth) acrylamide, N, N-dimethyl (Meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, (meth) acryloylaminopropyltrimethylammonium chloride, (meth) acryloyloxyethyltrimethylammonium chloride, ( Examples include (meth) acryloyloxyethyl triethylammonium chloride, (meth) acryloyloxyethylbenzyldimethylammonium chloride, and the like. Particularly preferred are dimethylaminoethyl (meth) acrylate, (meth) acryloyloxyethylbenzyldimethylammonium chloride, and the like.
The reason for selecting the a monomer is that fine dispersion and dispersion stabilization are possible, and high contrast can be achieved particularly when used for a color filter.

  Further, when the a monomer has an amino group, a compound that reacts with the amino group after appropriately copolymerizing with another polymerizable monomer, such as a phosphoric acid compound, a sulfonic acid compound, a carboxylic acid compound, etc. A part or all of the acid compound may be converted to a quaternary ammonium salt by reacting with an acid compound; a halogen compound such as an aryl halide, an alkyl halide, or an aralkyl halide;

Examples of the b monomer include styrene monomers such as styrene and α-methylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate (n-propyl acrylate), isopropyl (meth) acrylate, ( (Meth) acrylate monomers such as butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, and hydroxyethyl (meth) acrylate Vinyl acetate; acrylonitrile; allyl group-containing compounds such as allyl alkyl ether; and the like.
The reason for the selection of the b monomer is that fine dispersion and dispersion stabilization are possible, and high contrast can be achieved particularly when used for a color filter.

  When the polymerization block containing a monomer or a salt thereof is “A”, and the polymerization block containing b monomer is “B”, the basic block dispersant in the present invention is an AB block copolymer, A- The block may be any of a B-A block copolymer, a B-A-B block copolymer, an A-B-A-B block copolymer, and more block copolymers, preferably an A-B block. It is a copolymer.

  In the block copolymer containing a monomer or a salt thereof, the block part containing the a monomer or a salt thereof is adsorbed to the pigment (A), and the block part containing no a monomer or a salt thereof has an affinity for the solvent. Therefore, (A) the dispersibility of the pigment can be improved.

Specifically, what constitutes the salt is, for example, a salt formed with a tertiary amino group such as a unit forming a block copolymer with an acid such as a phosphoric acid compound or a sulfonic acid compound. Is mentioned.
In addition, a tertiary amino group such as dimethylaminoethyl (meth) acrylate, which is a unit forming a block copolymer, may be converted to a quaternary ammonium salt by aryl halide, aralkyl halide or the like.

The weight average molecular weight (Mw) of the basic block copolymer in the present invention is not particularly limited, but is preferably in the range of 500 to 100,000, more preferably in the range of 1000 to 30,000. It is particularly preferably within the range of ˜20,000, and most preferably 4,000 to 15,000.
By being within the above range, it is possible to achieve both “(A) wettability for uniformly dispersing the pigment” and dispersion stability. Further, when the pigment dispersant of the present application is used as a component of the photosensitive colored resin composition, when the upper limit is the above value or less, developability and resolution are not deteriorated, and the lower limit is the above value or more. Sufficient dispersibility is obtained.

Here, the weight average molecular weight is determined as a standard polystyrene conversion value by (Mw) and gel permeation chromatography (GPC).
The weight average molecular weight (Mw) of the basic block copolymer was measured using HLC-8120GPC manufactured by Tosoh Corporation and N-methylpyrrolidone added with 0.01 mol / L lithium bromide as an elution solvent. The calibration curve polystyrene standards are Mw377400, 210500, 96000, 50400, 20650, 10850, 5460, 2930, 1300, 580 (Easi PS-2 series manufactured by Polymer Laboratories) and Mw1090000 (manufactured by Tosoh Corporation). The measurement column is TSK-GEL ALPHA-M × 2 (manufactured by Tosoh Corporation).

The amine value is not particularly limited, but is preferably 5 to 250 mgKOH / g, more preferably 20 to 200 mgKOH / g, and particularly preferably 30 to 150 mgKOH / g.
If it is less than the lower limit, sufficient dispersion stability cannot be obtained, and if it is more than the upper limit, solubility in a solvent is lowered.
The amine value can be determined according to JIS-K7237.

The acid value is not particularly limited, but is preferably 0 mgKOH / g or more than 0 and preferably 100 mgKOH / g or less, particularly preferably 0 mgKOH / g or more than 0 and 50 mgKOH / g or less.
If the acid value is more than the upper limit, the resist pattern is likely to peel off.

When the molecular weight, amine value, or acid value is in the above range, it is easy to disperse, and it becomes possible to finely disperse in the “final dispersion step when preparing a pigment dispersion” or to shorten the dispersion time. Or Further, when used in combination with the above-described acidic dye derivative, the above-described effects of the present invention are easily exhibited synergistically.
As a result, a color display obtained using the pigment dispersion has a high contrast, a high light transmittance, and a high luminance display.

1-2-3. Basic Graft Type Dispersant The “basic graft type dispersant” refers to a basic dispersant composed of a (co) polymer in which repeating units are bonded as side chains to the main chain.
Specifically, a side chain is synthesized first and then (co) polymerized, that is, a macromonomer having a polymerizable unsaturated group at one end (having a polymerizable unsaturated group at one end). And a dispersant made of a (co) polymer having a polymerization component as an oligomer.
In addition, a (co) polymer in which a repeating unit is bonded to a pendant (like a branch) as a side chain after synthesizing a main chain in advance is composed of, and the like. The dispersing agent which becomes is mentioned.

The basicity of the “basic graft type dispersant” may be imparted in any way, but the basicity is preferably imparted by copolymerizing a basic nitrogen atom-containing monomer.
The basic monomer to be copolymerized is not particularly limited, and specific examples include the “a monomer” described in the section “Basic Block Dispersant”.

The "macromonomer having a polymerizable group unsaturated group at one end" is not particularly limited, and known ones can be used.
The polymerization component constituting the repeating unit in such a macromonomer is not particularly limited. Specifically, for example, styrene monomers such as styrene and α-methylstyrene; methyl (meth) acrylate, (meth) acrylic Ethyl acetate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, benzyl ( (Meth) acrylate monomers such as (meth) acrylate and hydroxyethyl (meth) acrylate; (meth) acrylamide, N-methylolacrylamide, N, N-dimethylacrylamide, N, N-dimethylaminoethylacrylamide, etc. ) Acrylamide mono Chromatography; vinyl acetate; acrylonitrile; allyl group-containing compounds such as allyl alkyl ether; and the like. The macromonomer in the present invention preferably has a unit in which the above polymerization component is polymerized.

In the “basic graft type dispersant”, in addition to the “macromonomer having a polymerizable group unsaturated group at one end” and the “basic monomer to be copolymerized”, other polymerizable monomers are copolymerized. Also good.
The “other polymerizable monomer” is not particularly limited, and specifically, for example, the “b monomer” described in the section of the “basic block dispersant” can be mentioned.

  The introduction rate of the macromonomer is not particularly limited, but it is preferably introduced at an average ratio of 0.1 to 20 in 100 repeating units of the main chain, and 0.3 to 10 It is particularly preferable to introduce them in proportions.

Although the molecular weight of the basic graft type dispersant in the present invention is not particularly limited, it is usually 1000 to 100,000, preferably 2000 to 40000, more preferably 3000 to 30000, particularly preferably as a weight average molecular weight (Mw) in terms of polystyrene. Is 4000-25000, more preferably 5000-20000.
Within the above range, it is easy to disperse, and fine dispersion can be achieved in the “final dispersion step when preparing a pigment dispersion”, or the dispersion time can be shortened. As a result, a color display obtained using the pigment dispersion has a high contrast, a high light transmittance, and a high luminance display.

1-3. (C) Solvent The method for producing a pigment dispersion of the present invention is a method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent. There is no limitation in particular as a solvent, A well-known thing is used.

(C) Although there is no limitation in particular as a solvent, Specifically, For example, Alcohol, such as methanol, ethanol, and propanol; Ethers, such as tetrahydrofuran; Propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol methyl ethyl ether Alkylene glycol ethers such as propylene glycol monoethyl ether and propylene glycol diethyl ether; dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and the like Dialkylene glycol ethers; tripropylene glycol monomethyl ether, Trialkylene glycol ethers such as propylene glycol dimethyl ether, tripropylene glycol methyl ethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol diethyl ether; alkylene glycol monoalkyl such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate Ether acetates; Dialkylene glycol monoalkyl ether acetates such as dipropylene glycol monomethyl ether acetate and dipropylene glycol monoethyl ether acetate; Trialkylene glycol compounds such as tripropylene glycol monomethyl ether acetate and tripropylene glycol monoethyl ether acetate Alkyl ether acetates; Aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone, methyl lulopyr ketone, methyl amyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; 2-hydroxypropionic acid Ethyl, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, butyl 3-methoxyacetate, butyl 3-methyl-3-methoxyacetate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy Esters such as methyl-2-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate ; Etc.
These solvents may be used alone or in combination of two or more.

  Among these, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethoxyethyl propionate, 3-methoxybutyl acetate, 3-methoxy-3-methyl-1-butyl acetate, and methyl 2-hydroxypropanoate are particularly preferable.

1-4. Content Ratio The present invention is a method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent. Here, (A) a pigment, (B) a dispersion The content ratio of the agent and (C) solvent is not particularly limited, but the following is preferable.
(A) With respect to 100 mass parts of pigments, (B) dispersant is preferably 5 to 200 mass parts, more preferably 10 to 150 mass parts, particularly preferably 15 to 100 mass parts, and 20 to 60 mass parts. Most preferred.
Moreover, 3-40 mass parts is preferable with respect to 100 mass parts of pigment dispersion liquid, 5-35 mass parts is more preferable, 7-30 mass parts is especially preferable.

When the content ratio of the (A) pigment and the (B) dispersant is the above, the (A) pigment is easily dispersed, and fine dispersion can be achieved in the “final dispersion step when preparing the pigment dispersion” described later. It becomes possible, excellent dispersion stability can be obtained, and dispersion time can be shortened.
As a result, a display using the color filter obtained by using the pigment dispersion liquid has a high contrast, a high light transmittance, and a high luminance display.

  Further, the above-mentioned “(A) pigment and (C) solvent content ratio” is excellent in dispersibility, dispersion stability and the like, and is adjusted to a suitable viscosity. D) When an alkali-soluble resin, (E) a polymerizable polyfunctional compound, and / or (F) a photopolymerization initiator is contained to obtain a photosensitive colored resin composition, the content ratio thereof becomes an optimum value. This is preferable because it is easy to adjust.

1-5. Final dispersion method (wet dispersion method)
The above-mentioned “(A) Pigment (a)” having an S / N of 90 or less is contained by wet dispersion in (C) solvent in the presence of (B) dispersant.
When wet dispersed, the pigment of the wet dispersion (A) is particularly effective when the S / N of the pigment (A) is 90 or less.
When the (A) pigment (a) having an S / N of 90 or less is wet-dispersed, fine dispersion can be achieved, dispersion time can be shortened, and the dispersion stability of difficult-to-disperse pigments can be improved. Can be.
Further, a display using a color filter obtained by using a pigment dispersion prepared by wet dispersion of the pigment (a) (A) has a high contrast, a high light transmittance, and a high luminance display. It becomes.

  Dispersers for performing wet dispersion include roll mills such as two rolls and three rolls; ball mills such as ball mills and vibration ball mills; paint shakers using beads; paint conditioners; continuous disk type bead mills, continuous annular type bead mills, etc. Bead mill; and the like.

As a preferable dispersion condition of a paint shaker or bead mill using beads, the bead diameter to be used is preferably 0.02 to 4 mm, more preferably 0.03 to 2 mm, and particularly preferably 0.05 to 1 mm.
Moreover, it is preferable to disperse | distribute in 2 steps | paragraphs or more with the bead mill from which a bead diameter differs. In that case, the bead diameter of the first stage bead mill is preferably 0.5 to 4 mm, more preferably 0.7 to 3 mm, and particularly preferably 0.8 to 2 mm. The bead diameter of the second and subsequent stages of the bead mill is preferably smaller than the first stage bead diameter, preferably 0.02 to 1 mm, more preferably 0.04 to 0.6 mm, and 0.05 to 0.3 mm. Particularly preferred.

  The material of the beads is preferably zirconia, alumina, glass, steel, cemented carbide, steel ball, ceramic or the like. Among these, steel beads, zirconia beads, ceramic beads or glass beads are preferable, and steel beads, zirconia beads or ceramic beads are particularly preferable. This is because it is excellent in wear resistance, chemical resistance, heat resistance, thermal conductivity, etc. and has a large specific gravity.

  In the present invention, the dispersion time for dispersion using the above-mentioned disperser is not particularly limited, but is preferably 0.01 to 50 hours, preferably 0.02 to 30 hours so that the dispersed particle diameter of the pigment is suitable. Is more preferable, and 0.05 to 10 hours is particularly preferable.

  Among the wet dispersions, in particular, by using the above-mentioned disperser and dispersion conditions, (A) the pigment (a) is finely dispersed, and high contrast is realized.

In the method for producing a pigment dispersion of the present invention, the above-mentioned dry dispersion treatment is followed by “the above S / N obtained by the dry dispersion treatment is 90 or less (A) the pigment (a), It is particularly preferable to perform “wet dispersion by blending the (B) dispersant and the (C) solvent”.
By performing the above-described wet dispersion following the above-described dry dispersion treatment, the pigment dispersion can be finely dispersed or the dispersion time of the wet dispersion can be shortened.
As a result of producing a pigment dispersion in which pigment is finely dispersed, a display using a color filter obtained using the pigment dispersion has a high contrast, a high light transmittance, and a high brightness display. .

Here, “continuously with the dry dispersion treatment” means that the following wet dispersion is performed after the dry dispersion treatment as a series of production procedures, and the (A) pigment (a) having an S / N of 90 or less. Is once stored in a separate container and stored for a long period of time (for example, stored for more than one month).
The period from the dry dispersion treatment to the wet dispersion treatment is preferably within one month, more preferably within two weeks, particularly preferably within one week, further preferably within two days, and within one day. Most preferred. This is because agglomerates are less likely to occur than when the pigment subjected to the dry dispersion treatment is stored for a long period of time (for example, stored for more than one month).
In addition, the operation of “wet dispersion is performed continuously after dry dispersion treatment” excludes salt milling instead of dry dispersion treatment before wet dispersion.

Among the above “continuous to the dry dispersion treatment”, the following operation is performed without temporarily storing the pigment (A) obtained by the dry dispersion treatment as it is (solid or in a solid state) in a separate container. It is preferable.
By doing in this way, compared with the case where (A) the pigment obtained by the dry dispersion treatment is once put in another container and stored for a long time (for example, stored for more than one month) and then the next operation is performed. As a result, the occurrence of aggregates is reduced, the fine dispersion of the pigment in the pigment dispersion is further possible, and the contrast is improved. In addition, the dispersion time of the wet dispersion is further shortened.

Particularly preferably, in the dry dispersion treatment container used for the dry dispersion treatment, in which (A) the pigment (a) having the S / N of 90 or less after the dry dispersion treatment is present is present. In addition, it is a “pigment dispersion production method” in which the above (A) pigment, the above (B) dispersant, and the above (C) solvent are blended by performing an operation of adding at least the above (C) solvent.
After the dry dispersion treatment is completed, the (C) solvent is added to the (A) pigment (a) present in the dry dispersion treatment vessel, and the (A) pigment is washed off with the (C) solvent, so that the following wet treatment is performed. It is also preferable to put it in a container used for dispersion.

By performing the wet dispersion continuously after the dry dispersion treatment, reaggregation can be prevented, fine dispersion can be facilitated, time can be saved, and costs can be reduced.
Further, compared with the case where salt milling is performed instead of the dry dispersion treatment, fine dispersion is possible in the subsequent wet dispersion, or the entire work time is shortened. As a result of producing a pigment dispersion in which pigment is finely dispersed, a display using a color filter obtained using the pigment dispersion has a high contrast, a high light transmittance, and a high brightness display. It becomes.

As long as the above-described object of the present invention can be achieved, in addition to (A) pigment (a), “(A) pigment with S / N exceeding 90” may be blended and wet dispersed. The ratio of the (A) pigment (a) having an S / N of 90 or less to the entire (A) pigment is not particularly limited, but the (A) pigment (a) is It is preferably 30% by mass or more, more preferably 50% by mass or more, particularly preferably 70% by mass or more, and further preferably 90% by mass or more.
(A) Pigment (a) and “(A) pigment with S / N exceeding 90” may be different types of pigments or the same type of pigments.
In the case of the same type of pigment, the 2θ of the main peak is the same, and therefore the S / N is preferably 90 or less for the entire (A) pigment contained.

1-6. Embodiment of Pigment Dispersion The average dispersion particle size of the pigment in the pigment dispersion produced by the method for producing a pigment dispersion of the present invention is not particularly limited, but is preferably 8 nm to 150 nm, more preferably 10 nm to 100 nm, and more preferably 12 nm. -70 nm is particularly preferred.
Here, the average dispersed particle diameter of the pigment in the pigment dispersion (hereinafter sometimes simply referred to as “average dispersed particle diameter”) is the dispersion of pigment particles dispersed in a dispersion medium containing at least a solvent. The particle size is measured by a laser light scattering particle size distribution meter. For the measurement of particle size with a laser light scattering particle size distribution meter, the pigment dispersion is appropriately diluted to a concentration that can be measured with a laser light scattering particle size distribution meter (for example, 1000 times, etc.) ), A laser light scattering particle size distribution meter (for example, Nanotrack particle size distribution measuring device UPA-EX150 manufactured by Nikkiso Co., Ltd.) is measured at 23 ° C. by a dynamic light scattering method. The average dispersed particle size here is a volume average particle size.

  If the average dispersed particle size is too small, light resistance may decrease. On the other hand, if the average dispersed particle size is too large, the display using the color filter obtained using the pigment dispersion has low contrast. Or the light transmittance may be low, or the display may not be a high brightness.

  After dispersion, it is usually filtered through a filter of 0.05 μm to 10.0 μm, preferably 0.1 μm to 5.0 μm, etc. to obtain the pigment dispersion of the present invention.

1-7. Use of Pigment Dispersion As described later, the pigment dispersion of the present invention is a color filter material, a colored resin composition for a color filter, a photosensitive colored resin composition for a color filter, a liquid crystal display material, an organic EL display material, and printing. Ink materials, paint materials, etc. In particular, it is useful as a colored resin composition for color filters.

2. Photosensitive colored resin composition Photosensitive colored resin comprising the pigment dispersion of the present invention containing at least (D) an alkali-soluble resin, (E) a polymerizable polyfunctional compound, and (F) a photopolymerization initiator. A color filter or the like is preferably obtained using the composition, and a liquid crystal display having the color filter and an organic EL display having the color filter have the effects of the present invention described above.

2-1. (D) Alkali-soluble resin Here, (D) alkali-soluble resin is not particularly limited, and any resin that can be suitably developed with an alkaline developer can be used.
(D) The alkali-soluble resin is preferably a copolymer having a monomer having an acid group as a copolymerization component. Moreover, what introduce | transduced the acid group into the polymer later may be used.

  Here, as a monomer having an acid group, a monomer having a carboxyl group such as (meth) acrylic acid or itaconic acid (methylene succinic acid); a monomer having a phenolic hydroxyl group such as 4-hydroxyphenylmaleimide; maleic anhydride, Monomers having a carboxylic anhydride group such as itaconic anhydride; and the like.

In addition, the (D) alkali-soluble resin in the present invention is one in which a radical polymerizable double bond is introduced, the sensitivity is improved, the photosensitive colored resin composition is image-exposed and photocured, and the unexposed portion is It is preferable from the viewpoint that a strong image can be formed as a result of development.
In order to introduce a radical polymerizable double bond, for example, a monomer capable of introducing a radical polymerizable double bond after polymerization is (co) polymerized, and then a radical polymerizable double bond as described later is introduced into the side chain. To do.
Examples of the “monomer capable of introducing a radical polymerizable double bond after polymerization” include, for example, monomers having a carboxyl group such as (meth) acrylic acid and itaconic acid; carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride Monomer having a group; and the like.

Examples of the compound used for introducing the radical polymerizable double bond include “epoxy group” such as glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, o- or m- or p-vinylbenzylglycidyl ether. And a radically polymerizable double bond ”.
A radical polymerizable double bond is introduced by reacting an epoxy group of a compound having “epoxy group and radical polymerizable double bond” with an acid group of “monomer capable of introducing a radical polymerizable double bond after polymerization”. The obtained (D) alkali-soluble resin is obtained.

  (D) In addition to the above, a monomer copolymerizable with these can be used for the alkali-soluble resin, and the monomer (hereinafter abbreviated as “other monomer”) is an ethylenically unsaturated double resin. Specific examples include monomers having a bond. Specifically, for example, styrene monomers such as styrene and α-methylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate (n-propyl acrylate), ( Such as isopropyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, and hydroxyethyl (meth) acrylate ( (Meth) acrylic acid ester monomers; (meth) acrylamide, N-methylolacrylamido (Meth) acrylamide monomers such as N, N-dimethylacrylamide and N, N-dimethylaminoethylacrylamide; vinyl acetate; acrylonitrile; allyl group-containing compounds such as allyl alkyl ether; maleimides such as benzylmaleimide and N-phenylmaleimide System monomers; and the like are copolymerized.

  The “monomer having an acid group”, “monomer capable of introducing a radical polymerizable double bond after polymerization”, “compound used for introducing a radical polymerizable double bond” and “other monomer” are used. In some cases, one or more of each is used and is subjected to (co) polymerization.

Although the acid value of (D) alkali-soluble resin in this invention does not have limitation in particular, 30-200 mgKOH / g is preferable, 40-150 mgKOH / g is more preferable, 50-120 mgKOH / g is especially preferable.
When the upper limit of the acid value is not more than the above value, sufficient adhesion to the substrate can be obtained, and when the lower limit is not less than the above value, sufficient alkali developability can be obtained.

Although the molecular weight of (D) alkali-soluble resin in this invention does not have limitation in particular, As a weight average molecular weight (Mw) of polystyrene conversion, it is 3000-25000 normally, Preferably, it is 4000-20000, Most preferably, it is 5000-15000. It is.
When the upper limit of the weight average molecular weight (Mw) is not more than the above value, the compatibility with other components is improved, and when the lower limit is not less than the above value, the adhesion to the substrate is improved.

2-2. (E) Polymerizable polyfunctional compound (E) The polymerizable polyfunctional compound is not particularly limited, and a known polymerizable polyfunctional compound is used.
The “polymerizable polyfunctional compound” is not particularly limited as long as it has two or more polymerizable functional groups in one molecule. For example, polyether (meth) acrylate, urethane (meth) acrylate, epoxy And polyfunctional (meth) acrylates such as (meth) acrylate; polyfunctional allyl compounds such as diallyl phthalate and triallyl isocyanurate;

Among these, specific examples of the polyether (meth) acrylate include the following.
Examples of the bifunctional (meth) acrylate include linear chains such as 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol di (meth) acrylate. Alkanediol di (meth) acrylate; diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol # 200 di (meth) acrylate, polyethylene glycol # 300 di (meta) ) Acrylate, polyethylene glycol # 400 di (meth) acrylate, polyethylene glycol # 600 di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) a Alkylene glycol di (meth) acrylates such as relate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol # 400 di (meth) acrylate, polypropylene glycol # 700 di (meth) acrylate; pentaerythritol di (meth) acrylate, pentaerythritol Partial (meth) acrylic acid esters of trihydric or higher alcohols such as di (meth) acrylate monostearate and pentaerythritol di (meth) acrylate monobenzoate; bisphenol A di (meth) acrylate, EO-modified bisphenol A di (meth) Acrylate, PO modified bisphenol A di (meth) acrylate, hydrogenated bisphenol A di (meth) acrylate, EO modified hydrogenated bisphenol A di (meth) acrylate Rate, PO modified hydrogenated bisphenol A di (meth) acrylate, bisphenol F di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, PO modified bisphenol F di (meth) acrylate, EO modified tetrabromobisphenol A di ( Bisphenol di (meth) acrylates such as (meth) acrylate; neopentyl glycol di (meth) acrylate, neopentyl glycol PO modified di (meth) acrylate; hydroxypivalic acid neopentyl glycol ester di (meth) acrylate, hydroxypivalic acid neo Caprolactone adduct di (meth) acrylate of pentyl glycol ester; 1,6-hexanediol bis (2-hydroxy-3-acryloyloxypropyl) ether; And lodecane dimethylol di (meth) acrylate, isocyanuric acid EO-modified di (meth) acrylate; and the like.

  Examples of the trifunctional (meth) acrylate include glycerin tri (meth) acrylate, glycerin PO-modified tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane EO-modified tri (meth) acrylate, and trimethylolpropane. PO-modified tri (meth) acrylate, isocyanuric acid EO-modified tri (meth) acrylate, isocyanuric acid EO-modified ε-caprolactone-modified tri (meth) acrylate, 1,3,5-triacryloylhexahydro-s-triazine, pentaerythritol tri (Meth) acrylate, dipentaerythritol tri (meth) acrylate tripropionate, etc. are mentioned.

  Examples of tetra- or higher functional (meth) acrylates include pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, succinic acid-modified dipentaerythritol penta (meth) acrylate, and dipentaerythritol penta (meth) acrylate. Examples thereof include monopropionate, dipentaerythritol hexa (meth) acrylate, tetramethylolethane tetra (meth) acrylate, and oligoester tetra (meth) acrylate.

  These are used alone or in combination.

Among these, specific examples of urethane (meth) acrylate include the following.
(A) As obtained by reacting a compound having (preferably a plurality of) isocyanate groups in the molecule with a compound having a hydroxyl group and (preferably a plurality) (meth) acryl groups in the molecule. A compound having a structure, (B) a compound having a plurality of hydroxyl groups is reacted with a diisocyanate compound or a triisocyanate compound, and an unreacted isocyanate group of the obtained compound is incorporated into a molecule such as hydroxyethyl (meth) acrylate. The thing which has a structure obtained by making the compound which has a hydroxyl group and a (meth) acryl group react is mentioned.

  The bifunctional urethane (meth) acrylate is obtained by reacting the diisocyanate compound (d) with both ends of a polymer or oligomer (c) such as a hydroxyl group or amino group at both ends, and having “isocyanate groups at both ends”. Examples of the “polymer or oligomer” include those obtained by reacting a compound (e) having a hydroxyl group and a (meth) acryl group in the molecule at both ends.

Examples of the polymer or oligomer (c) having hydroxyl groups at both ends include ester oligomers, ester polymers, urethane oligomers, urethane polymers, polyethylene glycol, and polypropylene glycol.
Examples of the diol component of the ester include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, and 2,2′-thiodiethanol. It is done.
Examples of the dicarboxylic acid component of the ester include alkylene dicarboxylic acids such as succinic acid, succinic acid, maleic acid, and adipic acid; and aromatic dicarboxylic acids such as terephthalic acid and phthalic acid.
As the diisocyanate compound (d) to be reacted at both ends of the polymer or oligomer, for example, the same diisocyanate compounds as described in the item of the polyvalent isocyanate compound (a) can be used.
Furthermore, the “compound (e) having a hydroxyl group and a (meth) acryl group in the molecule” to be reacted with both ends of the polymer or oligomer having an isocyanate group at both ends obtained above is not particularly limited. For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, ethylene glycol mono (meth) acrylate, propylene glycol mono (meth) acrylate and the like can be mentioned.

Examples of the tri- or more functional urethane (meth) acrylate include a compound (b) having one hydroxyl group and one or more (meth) acryl groups in the molecule on the isocyanate group of the polyvalent isocyanate compound (a). Examples thereof include those obtained by reaction of hydroxyl groups.
As the polyvalent isocyanate compound (a) in this case, for example, as a compound having two isocyanate groups in the molecule, for example, 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexa Methylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4′-di Cyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate, m- tetramethylxylylene diisocyanate, and the like.
Examples of the compound having three isocyanate groups in the molecule include trimethylolpropane-added adducts, burettes, isocyanates obtained by modifying isophorone diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and the like. A nurate body etc. are mentioned.

Examples of the compound (b) having one hydroxyl group and one or more (meth) acryl groups in the molecule include hydroxyethyl (meth) acrylate; three or more (p) hydroxyl groups in the molecule. Examples include a compound obtained by reacting (p-1) (meth) acrylic acid with the hydroxyl group of the compound (b-1), a compound obtained by ring-opening reaction of glycidyl (meth) acrylate and (meth) acrylic acid, and the like.
Among the compounds (b), in “a compound in which (p-1) (meth) acrylic acid has reacted with a compound (b-1) having p (p is an integer of 3 or more) hydroxyl groups in the molecule” ” As the “compound (b-1) having three or more hydroxyl groups in the molecule”, for example, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, tetramethylolethane, diglycerin, ditrimethylolethane, ditrimethylol Propane, dipentaerythritol, ditetramethylolethane; these ethylene oxide modified compounds; these propylene oxide modified compounds; ethylene oxide modified compounds of isocyanuric acid, propylene oxide modified compounds, ε-caprolactone modified compounds; oligoesters, etc. .
Specific examples of the compound (b-1) include diglycerin, ditrimethylolethane, ditrimethylolpropane, dipentaerythritol, ditetramethylolethane, and the like.

  These are used alone or in combination.

Among these, specific examples of the epoxy (meth) acrylate include, for example, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, triethylene glycol Diglycidyl ethers of alkylene glycols such as propylene glycol diglycidyl ether; glycerin glycidyl ethers such as glycerin diglycidyl ether; bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, PO-modified diglycidyl ether of bisphenol A , Diglycidyl ethers of bisphenol compounds such as bisphenol F diglycidyl ether, (meth) Such as those having a structure obtained by adding acrylic acid.
Moreover, what has the structure which added (meth) acrylic acid to the polycondensation epoxy resin is mentioned.
Furthermore, the epoxy resin having a structure obtained by reacting, for example, epichlorohydrin or the like with a polycondensation product such as phenol novolak or cresol novolak has a structure in which (meth) acrylic acid is added, And those having an acid anhydride added thereto.

  These are used alone or in combination.

2-3. (F) Photopolymerization initiator (F) The photopolymerization initiator is not particularly limited, and known ones conventionally used for radical polymerization can be used. In particular, it is preferable to use what is generally used for manufacturing color filters.

  As such a photopolymerization initiator, specifically, a compound that generates free radicals by the energy of ultraviolet rays, which is a benzoin derivative; a benzophenone derivative; a xanthone derivative such as xanthone, diethylthioxanthone, isopropylthioxanthone, or a thioxanthone derivative; Irgacure OX-01, Irgacure OXE-02 (manufactured by BASF Japan); oxime ester compounds such as ADEKA OPT-N-1919 (manufactured by Asahi Denka); chlorosulfonyl, chloromethyl polynuclear aromatic compounds, chloromethyl heterocyclic Compounds, halogen-containing compounds such as chloromethylbenzophenones; triazines; fluorenones; haloalkanes; redox couples of photoreducing dyes and reducing agents; organic sulfur compounds; peroxides; It is.

  Specific examples of the photopolymerization initiator include Michler's ketone, 4,4′-bisdiethylaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2-ethylanthraquinone, phenanthrene and other aromatic ketones, benzoin methyl Benzoin ethers such as ether, benzoin ethyl ether and benzoin phenyl ether, benzoin such as methyl benzoin and ethyl benzoin, 2- (o-chlorophenyl) -4,5-phenylimidazole dimer, 2- (o-chlorophenyl)- 4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole Dimer, 2,4,5-triali Ruimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methylphenyl) imidazole dimer, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5- (p-cyanostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5 Halomethylthiazole compounds such as-(p-methoxystyryl) -1,3,4-oxadiazole, 2,4-bis (trichloromethyl) -6-p-methoxystyryl-s-triazine, 2,4-bis (Trichloromethyl) -6- (1-p-dimethylaminophenyl-1,3-butadienyl) -s-triazine, 2-trichloromethyl-4-amino-6- -Methoxystyryl-s-triazine, 2- (naphth-1-yl) -4,6-bis-trichloromethyl-s-triazine, 2- (4-ethoxy-naphth-1-yl) -4,6-bis Halomethyl-s-triazine compounds such as trichloromethyl-s-triazine, 2- (4-butoxy-naphth-1-yl) -4,6-bis-trichloromethyl-s-triazine, 2,2-dimethoxy- 1,2-diphenylethane-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone, 1,2-benzyl-2-dimethylamino-1- (4-morpholino Phenyl) -butanone-1,1-hydroxy-cyclohexyl-phenyl ketone, methyl benzoylbenzoate, 4-benzoyl-4′-methyldiphenyl sulfide , Benzylmethyl ketal, dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, 2-n-butoxyethyl-4-dimethylaminobenzoate, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, isopropyl Thioxanthone, ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (o-acetyloxime), 4-benzoyl-methyldiphenyl sulfide, 1-hydroxy- Cyclohexyl-phenyl ketone, 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone, 2- (dimethylamino) -2-[(4-methylphenyl) ) Methyl] -1- [4- (4-morpholini) ) Phenyl] -1-butanone, α-dimethoxy-α-phenylacetophenone, phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone, 1,2-octadione and the like.

Moreover, the photoinitiator which has a tertiary amine structure can be used suitably. Since the photopolymerization initiator having a tertiary amine structure has a tertiary amine structure that is an oxygen quencher in the molecule, radicals generated from the photopolymerization initiator are not easily deactivated by oxygen, and sensitivity can be improved. It has the advantage that it can.
As a commercial item of the photoinitiator which has the said tertiary amine structure, Irgacure 907, Irgacure 369 (above, BASF Japan make), high cure ABP (made by Kawaguchi Pharmaceutical) etc. are mentioned, for example.

  The photoinitiator used for this invention is not limited to 1 type, You may use combining 2 or more types.

2-4. Content Ratio From the viewpoints of sensitivity, resolution, and developability in the photosensitive colored resin composition, the content ratio of (D) the alkali-soluble resin and (E) the polymerizable polyfunctional compound is not particularly limited. ) With respect to 100 parts by mass of the alkali-soluble resin, (E) the polymerizable polyfunctional compound is preferably 10 to 500 parts by mass, more preferably 20 to 300 parts by mass, and particularly preferably 30 to 200 parts by mass.
5-60 mass% is preferable and (D) alkali-soluble resin is more preferable with respect to solid content total amount of the photosensitive coloring resin composition, and 10-40 mass%. Moreover, 5-60 mass% is preferable with respect to this solid content whole quantity, and (E) polymeric polyfunctional compound has more preferable 10-40 mass%.

The content ratio of the (F) photopolymerization initiator is usually 0.2 to 30 parts by weight, preferably 0, with respect to 100 parts by weight of the polymerizable polyfunctional compound (E) from the viewpoints of sensitivity, resolution and developability. .5 to 20 parts by weight, particularly preferably 1 to 10 parts by weight.
3-40 mass% is preferable with respect to the solid content total amount of the photosensitive coloring resin composition, 3-40 mass% is preferable, 7-35 mass% is more preferable, and 10-30 mass% is especially preferable.

The pigment (A) is preferably 5 to 50% by mass and more preferably 10 to 45% by mass with respect to the total solid content of the photosensitive colored resin composition.
Within this range, the coloring power, sensitivity, resolution and developability will be good.

2-5. Other components The photosensitive colored resin composition further includes, for example, a surfactant for improving wettability, a leveling agent, a silane coupling agent for improving adhesion, an antifoaming agent, and repellency prevention. Agents, antioxidants, anti-aggregation agents, ultraviolet absorbers and the like can be included.

2-6. Preparation of photosensitive colored resin composition The photosensitive colored resin composition was prepared by adding at least (D) an alkali-soluble resin, (E) a polymerizable polyfunctional compound, and (F) a photopolymerization initiator to a pigment dispersion. If necessary, "other components" can be added, and if necessary, a solvent can be added and mixed.
As the pigment dispersion, the pigment dispersion according to the present invention and, if necessary, further another pigment dispersion may be mixed during the preparation of the photosensitive colored resin composition.
Since the photosensitive colored resin composition of the present invention is prepared and used in advance, the pigment dispersion can be effectively prevented and dispersed uniformly.

3. Color filter The color filter usually has a transparent substrate, a light shielding part and a colored layer. The color filter obtained using the pigment dispersion of the present invention or obtained using the photosensitive colored resin composition can achieve high contrast and the like. It is useful as a color filter material, a colored resin composition for color filters, and a photosensitive colored resin composition for color filters.

3-1. Colored layer The colored layer is not particularly limited as long as it is formed by curing the above-described photosensitive colored resin composition of the present invention. Usually, it is formed at the opening of the light shielding part on the transparent substrate described later. Depending on the type of pigment contained in the photosensitive colored resin composition, it is composed of three or more colored patterns.
In addition, the arrangement of the colored layers is not particularly limited, and for example, a general arrangement such as a stripe type, a mosaic type, a triangle type, or a four-pixel arrangement type can be used. Moreover, the width | variety, area, etc. of a colored layer can be set arbitrarily.
The thickness of the colored layer is appropriately controlled by adjusting the coating method, coating conditions, solid content concentration, viscosity, and the like of the photosensitive colored resin composition, but is usually preferably in the range of 1 to 5 μm. .

The colored layer can be formed by the following method, for example.
First, the above-described photosensitive colored resin composition of the present invention is applied onto a transparent substrate described later using coating means such as spray coating, dip coating, bar coating, roll coating, spin coating, and die coating. Apply to form a wet coating.
Next, after the wet coating film is dried using a hot plate, an oven, or the like, it is exposed through a mask having a predetermined pattern, and (D) an alkali-soluble resin and (E) a polymerizable polyfunctional compound. Is photopolymerized.
Examples of the light source used for exposure include ultraviolet rays such as a low-pressure mercury lamp, a high-pressure mercury lamp, and a metal halide lamp, and an electron beam.
Moreover, in order to promote a polymerization reaction after exposure, you may heat-process.

Next, it develops using a developing solution, a coating film is formed with a desired pattern by melt | dissolving and removing an unexposed part. As the developer, a solution in which an alkali is dissolved in water or a water-soluble solvent is usually used.
After the development treatment, the developer is usually washed and the cured coating film of the resin composition is dried to form a colored layer. In addition, you may heat-process in order to fully harden a coating film after image development processing.

3-2. Light-shielding part The light-shielding part in the color filter is formed in a pattern on a transparent substrate described later.
The pattern shape of the light shielding part is not particularly limited, and examples thereof include a stripe shape and a matrix shape.
Examples of the light-shielding portion include those obtained by dispersing or dissolving a black pigment in a binder resin; metal thin films such as chromium and chromium oxide. This metal thin film may be a laminate of a CrOx film (x is an arbitrary number) and a Cr film, or a CrOx film (x is an arbitrary number) with a reduced reflectance, CrNy A film (y is an arbitrary number) and three layers of Cr films may be laminated.

In the case where the light shielding part is obtained by dispersing or dissolving a black colorant in a binder resin, examples of a method for forming the light shielding part include a photolithography method, a printing method, and an inkjet using a resin composition for the light shielding part. The law etc. can be mentioned.
In the above case, when a printing method or an inkjet method is used as a method for forming the light shielding part, examples of the binder resin include polymethyl methacrylate resin, polyacrylate resin, polycarbonate resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, Examples thereof include hydroxyethyl cellulose resin, carboxymethyl cellulose resin, polyvinyl chloride resin, melamine resin, phenol resin, alkyd resin, epoxy resin, polyurethane resin, polyester resin, maleic acid resin, polyamide resin and the like.

In the above case, when a photolithography method is used as a method for forming the light shielding portion, the binder resin may be, for example, an acrylate-based, methacrylate-based, polyvinyl cinnamate-based, or cyclized rubber-based reactive material. A photosensitive resin having a vinyl group is used.
In this case, a photopolymerization initiator, a sensitizer, a coatability improver, a development improver, a crosslinker is included in the light shielding part resin composition containing a black pigment such as carbon black or titanium black as a pigment and a photosensitive resin. Further, a polymerization inhibitor, a plasticizer, a flame retardant, etc. may be added.

  On the other hand, when the light-shielding part is a metal thin film, the light-shielding part can be formed by, for example, masking a resist pattern formed on the metal thin film by a photolithography method using a metal thin film formed by vacuum deposition or sputtering. Examples of the method include metal etching.

  The film thickness of the light-shielding part is set to about 0.05 to 0.4 μm in the case of a metal thin film, and 0.5 to 0.5 in the case where a black colorant is dispersed or dissolved in a binder resin. It is set at about 3 μm.

3-3. Transparent substrate The transparent substrate in the color filter is not particularly limited as long as it is a base material transparent to visible light, and a transparent substrate used for a general color filter can be used. Specific examples include inflexible transparent rigid materials such as quartz glass, alkali-free glass, and synthetic quartz plates, or transparent flexible materials having flexibility such as transparent resin films and optical resin plates. It is done.
Although the thickness of the said transparent substrate is not specifically limited, Depending on a use, the thing of about 100 micrometers-1 mm can be used, for example.
The color filter of the present invention may be one in which, for example, an overcoat layer, a transparent electrode layer, an alignment film, a columnar spacer, or the like is formed in addition to the transparent substrate, the light shielding portion, and the colored layer. .

4). Liquid crystal display and organic EL display The color filter obtained by using the photosensitive colored resin composition containing the pigment dispersion of the present invention is used in a display device such as a liquid crystal display or an organic EL display.
Application of the color filter to a liquid crystal display or an organic EL display is usually performed by a known method.

The color filter obtained by using the photosensitive colored resin composition containing the pigment dispersion of the present invention is a liquid crystal display or organic EL display having a high contrast, a high light transmittance, and a high luminance display. .
In particular, a color filter for a liquid crystal display obtained by using the pigment dispersion of the present invention has a finely dispersed pigment and rarely cancels the polarization obtained by the liquid crystal substance. For example, a liquid crystal display having high contrast, high transmittance, and high luminance can be provided.

The actions and effects of the pigment dispersion of the present invention exhibiting excellent dispersibility, contrast and the like are not clearly apparent, but the following may be considered. However, the present invention is not limited to the range of the following effects.
The (A) pigment (a) having (S / N) of 90 or less in the present invention is considered to be low in fastness of the (A) pigment because of low crystallinity. Thereby, it is considered that (A) the pigment (a) is easily miniaturized by pulverization and dispersion, that is, the fine dispersion of the pigment is facilitated.
Therefore, the pigment dispersion can exhibit excellent dispersibility, contrast, and the like. In particular, when combined with the (B) dispersant of the present application, the dispersibility, contrast and the like can be further improved synergistically.

Hereinafter, the present invention will be described more specifically with reference to production examples, examples and comparative examples. However, the present invention is not limited to these examples as long as the gist thereof is not exceeded.
In the examples, C.I. I. Pigment Red 177 etc. are simply referred to as “PR177” etc., and C.I. I. Pigment Yellow 150 and the like are simply referred to as “PY150” and the like. I. Pigment Yellow 180 etc. is simply referred to as “PY180” etc .; I. Pigment Yellow 213 and the like are simply referred to as “PY213” and the like. I. Pigment Blue 15: 6 etc. is simply referred to as “PB15: 6” etc .; I. Pigment Violet 23 or the like may be simply abbreviated as “PV23” or the like.

<(A) Preparation of pigment>
Preparation Example 1
(Preparation of dry dispersion treatment pigment A)
C.I. with S / N of 110 as pigment. I. Pigment Red 177 (PR177) 10.0 parts by mass and particle size 10.0 mm of zirconia beads 200 parts by mass are placed in a mayonnaise bin, shaken with a paint shaker (manufactured by Asada Tekko Co., Ltd.) for 9 hours, and then subjected to dry dispersion treatment. Pigment A was prepared. The S / N of the dry dispersion-treated pigment A was 24.

Preparation Example 2
(Preparation of dry dispersion treatment pigment B)
C.I. with S / N of 122 as pigment. I. Pigment Yellow 150 (PY150) 10.0 parts by weight, particle size 10.0 mm zirconia beads 200 parts by weight are placed in a mayonnaise bin, shaken for 9 hours in a paint shaker (manufactured by Asada Tekko Co., Ltd.), and dry dispersion treatment Pigment B was prepared. The S / N of the dry dispersion-treated pigment B was 26.

Preparation Example 3
(Preparation of dry dispersion treatment pigment C)
As a pigment, C.I. I. Pigment Yellow 180 (PY180) 10.0 parts by mass and particle size 10.0 mm of zirconia beads 200 parts by mass are placed in a mayonnaise bin, shaken with a paint shaker (manufactured by Asada Tekko Co., Ltd.) for 9 hours, and then subjected to dry dispersion treatment. Pigment C was prepared. The S / N of the dry dispersion-treated pigment C was 54.

Preparation Example 4
(Preparation of dry dispersion treatment pigment D)
C.I. of S / N of 259 as pigment. I. Pigment Yellow 213 (PY213) 10.0 parts by mass, particle size 10.0 mm zirconia beads 200 parts by mass are put into a mayonnaise bin, shaken for 9 hours in a paint shaker (manufactured by Asada Tekko Co., Ltd.), and dry dispersion treatment Pigment D was prepared. The S / N of the dry dispersion-treated pigment D was 48.

Preparation Example 5
(Preparation of dry dispersion treatment pigment E)
C.I. with S / N of 102 as pigment. I. Pigment Blue 15: 6 (PB15: 6) 10.0 parts by mass, propylene glycol monomethyl ether acetate (PGMEA) (hereinafter simply referred to as “PGMEA”) 5.0 parts by mass, particle size 10.0 mm zirconia beads 200 parts by mass The portion was placed in a mayonnaise bin and shaken for 9 hours with a paint shaker (manufactured by Asada Tekko Co., Ltd.) to prepare dry dispersion pigment E. The S / N of dry dispersion-treated pigment E was 29.

Preparation Example 6
(Preparation of dry dispersion-treated pigments F to H)
C.I. having S / N of 221 as a pigment. I. Pigment Violet 23 (PV23) 10.0 parts by weight, particle size 10.0 mm zirconia beads 200 parts by weight are placed in a mayonnaise bin, and shaken for 6, 9, and 12 hours with a paint shaker (manufactured by Asada Tekko Co., Ltd.), respectively. Dry dispersion-treated pigments F, G and H were prepared. The S / N ratios of the dry dispersion-treated pigments F, G, and H were 25, 10, and 2, respectively.

Preparation Example 7
(Preparation of dry dispersion-treated pigment I)
C.I. having S / N of 221 as a pigment. I. Pigment Violet 23 (PV23) 10.0 parts by mass, particle size 10.0 mm zirconia beads 200 parts by mass are placed in a mayonnaise bin, shaken with a paint shaker (manufactured by Asada Tekko Co., Ltd.) for 12 hours, and then a dry dispersion pigment P ′ was prepared. The S / N of the dry dispersion-treated pigment P ′ was 2.
After the preparation, the dry dispersion-treated pigment was transferred to a container and stored at room temperature for 3 months. Dry dispersion-treated pigment P ′ stored for 3 months at room temperature was designated as dry dispersion-treated pigment I. The S / N of the dry dispersion-treated pigment I was 2.

<(B) Synthesis of dispersant>
Synthesis example 1
(Synthesis of basic block dispersant)
Into a 500 mL round bottom four-necked separable flask equipped with a condenser, addition funnel, nitrogen inlet, mechanical stirrer and digital thermometer, 250 parts by mass of tetrahydrofuran (THF) and initiator dimethyl ketene methyltrimethylsilyl acetal 5.81 Part by mass was added through an addition funnel, and nitrogen substitution was sufficiently performed.
Thereafter, 0.5 part by mass of a 1 mol / L acetonitrile solution of tetrabutylammonium m-chlorobenzoate as a catalyst was injected using a syringe, and 100 parts by mass of the first monomer methyl methacrylate was added using an addition funnel. It was added dropwise over a period of minutes. The temperature was kept below 40 ° C. by cooling the reaction flask with an ice bath.
After 1 hour, 33.3 parts by mass of dimethylaminoethyl methacrylate as the second monomer was added dropwise over 20 minutes. After reacting for 1 hour, 1 part by mass of methanol was added to stop the reaction.

  The THF solution of the obtained basic block copolymer was reprecipitated in hexane, purified by filtration and vacuum drying, and a block copolymer A was obtained. Moreover, in use, it adjusted with PGMEA so that solid content might be 20 mass%.

  The weight average molecular weight (Mw) and the like of the basic block copolymer A thus obtained were confirmed by GPC under the above-mentioned conditions. As a result, methyl methacrylate (MMA) and dimethylaminoethyl methacrylate (DMAEMA) The composition ratio MMA / DMAEMA mass ratio was 3/1, the weight average molecular weight (Mw) was 8120, the number average molecular weight (Mn) was 6840, and the molecular weight distribution (Mw / Mn) was 1.19. It was. This basic block copolymer A was used as a “basic block type dispersant”.

Synthesis example 2
(Synthesis of basic graft type dispersant)
<< Synthesis of Macromonomer A >>
A reactor equipped with a condenser, an addition funnel, a nitrogen inlet, a mechanical stirrer, and a digital thermometer was charged with 80.0 parts by mass of PGMEA and heated to 90 ° C. while stirring under a nitrogen stream.
MMA 50.0 parts by mass, methacrylate-n-butyl (BMA) 30.0 parts by mass, benzyl methacrylate (BzMA) 20.0 parts by mass, mercaptoethanol 4.0 parts by mass, PGMEA 30 parts by mass A mixed solution of 1.0 part by mass of α, α′-azobisisobutyronitrile (AIBN) was added dropwise over 1.5 hours, followed by further reaction for 3 hours.

  Next, the nitrogen stream was stopped, the reaction solution was cooled to 80 ° C., 8.74 parts by mass of 2-isocyanatoethyl methacrylate (Karenz MOI (manufactured by Showa Denko KK)), dibutyltin dilaurate was added to a concentration of 0.8. 125 g, 0.125 parts by mass of p-methoxyphenol and 10 parts by mass of PGMEA were added and stirred for 3 hours to obtain a 49.5% solution of Macromonomer A.

  The weight average molecular weight (Mw) and the like of the obtained macromonomer A were measured by GPC in the same manner as the basic block copolymer. Macromonomer A had a weight average molecular weight (Mw) of 4010, a number average molecular weight (Mn) of 1910, and a molecular weight distribution (Mw / Mn) of 2.10.

<< Synthesis of Basic Graft Copolymer Using Macromonomer A >>
A reactor equipped with a condenser, an addition funnel, a nitrogen inlet, a mechanical stirrer, and a digital thermometer was charged with 80.0 parts by mass of PGMEA and heated to 85 ° C. while stirring under a nitrogen stream.
75.76 parts by mass of macromonomer A solution obtained in Synthesis Example 2 (effective solid content 37.5 parts by mass), 12.5 parts by mass of DMAEMA, 1.24 parts by mass of N-dodecyl mercaptan, 20.0 parts by mass of PGMEA, AIBN0 .5 parts by mass of the mixed solution mixed solution was added dropwise over 1.5 hours, heated and stirred for 3 hours, and then a mixed solution of AIBN 0.10 parts by mass and PGMEA 10.0 parts by mass was added dropwise over 10 minutes. By aging at a temperature for 1 hour, a basic graft copolymer solution was obtained.
The obtained basic graft copolymer solution was reprecipitated in hexane, purified by filtration and vacuum drying, and basic graft copolymer A was obtained. This basic graft copolymer A was used as a “basic graft type dispersant”.

  Moreover, in use, it adjusted with PGMEA so that solid content might be 20 mass%. The weight average molecular weight (Mw) and the like of the basic graft copolymer A thus obtained were measured by GPC in the same manner as the basic block copolymer. The basic graft copolymer A had a weight average molecular weight (Mw) of 11480, a number average molecular weight (Mn) of 4650, and a molecular weight distribution (Mw / Mn) of 2.47.

<Manufacture of pigment dispersion>
Production Example 1
(Production of pigment dispersion A)
As a dispersant, 8 parts by mass of the basic block type dispersant A synthesized in Synthesis Example 1 (solid content 1.6 parts by mass), 5 parts by mass of the dry dispersion-treated pigment A prepared in Preparation Example 1, and PGMEA 37 parts by mass, particle size 2.0 mm 50 parts by mass of zirconia beads are put into a mayonnaise bin, shaken for 1 hour with a paint shaker (manufactured by Asada Tekko Co., Ltd.) as a preliminary crush, and then particle size 2.0 mm The zirconia beads were taken out, 100 parts by mass of zirconia beads having a particle size of 0.1 mm were added, and similarly disintegrated for 3 hours using a paint shaker to produce pigment dispersion A. The dry dispersion-treated pigment A prepared in Preparation Example 1 was used within one day after preparation.

Production Example 2
(Production of pigment dispersions B to I)
A pigment dispersion was produced in the same manner as in Production Example 1, except that the dry dispersion-treated pigment A used in Production Example 1 was replaced with the dry-dispersed pigments B to I prepared in Preparation Examples 2 to 7, respectively. Then, pigment dispersions B to I were prepared corresponding to “B to I”, respectively. The dry dispersion-treated pigments B to H prepared in Preparation Examples 2 to 6 were used within one day after preparation, and the dry dispersion-treated pigment I prepared in Preparation Example 7 was used three months after the preparation. .

Production Example 3
(Production of pigment dispersions J to L)
As a dispersant, 8 parts by mass (basic content 1.6 parts by mass) of the basic graft copolymer solution A synthesized in Synthesis Example 2 and 5 parts by mass of the dry dispersion-treated pigments F to H prepared in Preparation Example 6 were used. , 37 parts by mass of PGMEA and 50 parts by mass of zirconia beads having a particle size of 2.0 mm were placed in a mayonnaise bin, shaken for 1 hour in a paint shaker (manufactured by Asada Tekko Co., Ltd.) as a preliminary crushing, and then the particle size The 2.0 mm zirconia beads were taken out, 100 parts by mass of zirconia beads having a particle size of 0.1 mm were added, and similarly disintegrated for 3 hours using a paint shaker to produce pigment dispersions J to L. The dry dispersion-treated pigments F to H prepared in Preparation Example 6 were used within one day after preparation.

Preparation Example 8
(Preparation of dry dispersion treatment pigment M)
C.I. having S / N of 221 as a pigment. I. 10.2 parts by mass of Pigment Violet 23 (PV23) and 200 parts by mass of zirconia beads having a particle size of 10.0 mm were placed in a mayonnaise bin, shaken with a paint shaker (manufactured by Asada Tekko Co., Ltd.) for 12 hours, and dry dispersion Treated pigment M was prepared.
When 0.2 parts by mass of the dry dispersion-treated pigment M was taken out from the mayonnaise bin and measured with an X-ray diffractometer at a later date, the S / N was 2.

Production Example 4
(Production of pigment dispersion M)
Subsequently, 74.0 parts by mass of PGMEA was added to mayonnaise bin in which the dry dispersion-treated pigment M used in Preparation Example 8 was present, and after shaking for 5 minutes in a paint shaker, the particle size was 10.0 mm. The zirconia beads were removed, and the PGMEA solution of the dry dispersion-treated pigment M was recovered.
In another mayonnaise bin, 42 parts by mass of the PGMEA solution of the dry dispersion pigment M, 8 parts by mass of the basic block copolymer solution A synthesized in Synthesis Example 1 (1.6 parts by mass of solid content) as a dispersant, Add 50 parts by weight of zirconia beads with a particle size of 2.0 mm, shake for 1 hour with a paint shaker (manufactured by Asada Tekko Co., Ltd.) as a preliminary crush, then take out the zirconia beads with a particle size of 2.0 mm A pigment dispersion M was produced by adding 100 parts by mass of zirconia beads having a diameter of 0.1 mm and dispersing the mixture for 3 hours with a paint shaker in the same manner.

Production Example 5
(Production of pigment dispersion N)
As a dispersant, 8 parts by mass of the basic block type dispersant A synthesized in Synthesis Example 1 (solid content 1.6 parts by mass) and 4.7 parts by mass of the dry dispersion-treated pigment H prepared in Preparation Example 6 were used. As an “acidic dye derivative”, 0.3 parts by mass of “sulfonic acid derivative of PV23” synthesized by the method described in JP-A-2005-173659, 37 parts by mass of PGMEA, and 50 masses of zirconia beads having a particle size of 2.0 mm Is placed in a mayonnaise bin, shaken for 1 hour with a paint shaker (manufactured by Asada Tekko Co., Ltd.) as a preliminary crush, and then the zirconia beads 100 having a particle size of 0.1 mm are taken out. The pigment dispersion liquid N was manufactured by adding 3 parts by mass and dispersing the mixture for 3 hours in a paint shaker in the same manner.

Comparative production example 1
(Production of pigment dispersion A ′)
A pigment dispersion was produced in the same manner as in Production Example 1 except that the dry dispersion-treated pigment A used in Production Example 1 was replaced with the untreated PR177 (S / N = 110) used in Preparation Example 1. And pigment dispersion A ′.

Comparative production example 2
(Production of pigment dispersions B ′ to F ′)
Pigment dispersions were prepared in the same manner as in Production Example 2, except that the dry dispersion-treated pigments B to E used in Production Example 2 were replaced with the untreated pigments of the dry dispersion-treated pigments used in Production Example 2, respectively. Were prepared as pigment dispersions B ′ to E ′ corresponding to the dry dispersion pigments B to E, respectively.
Moreover, it corresponds to Production Example 2 except that the dry dispersion treatment pigments F, G, and H (only the dry dispersion treatment time is different and common to PV23) are changed to PV23 not subjected to the dry dispersion treatment. A pigment dispersion was produced by the method and designated as pigment dispersion F ′.

Comparative Production Example 3 (Production of pigment dispersion G ′)
Same as Production Example 3, except that the dry dispersion-treated pigments F, G, and H used in Production Example 3 were replaced with the untreated pigment PV23 of the dry dispersion-treated pigment used in Production Example 3. A pigment dispersion was prepared by the method described above to obtain a pigment dispersion G ′.

Synthesis example 3
(Synthesis of alkali-soluble resin)
A polymerization tank was charged with 300 parts by mass of PGMEA, heated to 100 ° C. in a nitrogen atmosphere, 90 parts by mass of phenoxyethyl methacrylate (PhEMA), 54 parts by mass of methyl methacrylate (MMA), and 36 parts by mass of methacrylic acid (MAA). And 6 parts by mass of perbutyl O (manufactured by NOF Corporation) and 2 parts by mass of a chain transfer agent (N-dodecyl mercaptan) were continuously added dropwise over 1.5 hours.

Thereafter, the reaction was continued while maintaining 100 ° C., and after 2 hours from the completion of dropping of the main chain forming mixture, 0.1 part by mass of p-methoxyphenol was added as a polymerization inhibitor to terminate the polymerization.
Next, 20 parts by mass of glycidyl methacrylate (GMA) was added as an epoxy group-containing compound while blowing air, and the temperature was raised to 110 ° C., then 0.8 parts by mass of triethylamine was added and added at 110 ° C. for 15 hours. By reacting, an alkali-soluble resin A (weight average molecular weight (Mw) 8500, acid value 75 mgKOH / g, solid content 40% by mass) was obtained.
In addition, the said weight average molecular weight (Mw) of alkali-soluble resin was measured by the Shodex GPC system-21H (polystyrene) as a standard substance and THF as an eluent with Shodex GPC System-21H. The acid value was measured based on JIS K 0070.

Example 1
(D) Alkali-soluble resin A: 1.28 parts by mass (E) Polymerizable polyfunctional compound (trade name: Aronix M403, manufactured by Toagosei Co., Ltd.): 1.19 parts by mass (F) Photopolymerization initiator 2-methyl- 1 [4- (Methylthio) phenyl] -2-morpholinopropan-1-one (trade name: Irgacure 907, manufactured by BASF): 0.17 parts by mass 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butanone-1 (trade name: Irgacure 369, manufactured by BASF): 0.13 parts by mass

  To the above composition, 5.28 parts by mass of PGMEA was added and stirred to obtain a transparent resist composition. To the obtained transparent resist composition, 11.95 parts by mass of the pigment dispersion A obtained in Production Example 1 was added to obtain a photosensitive colored resin composition which is a red resist composition.

Examples 2 to 4 and Comparative Examples 1 to 4
Except that the pigment dispersion A used in Example 1 was replaced with the pigment dispersions B to D obtained in Production Example 2 and the pigment dispersions A ′ to D ′ obtained in Comparative Production Examples 1 and 2. A photosensitive colored resin composition, which is a colored resist composition, was obtained in the same manner as in Example 1.

Example 5
(D) Alkali-soluble resin A: 1.78 parts by mass (E) Polymerizable polyfunctional compound (trade name: Aronix M403, manufactured by Toagosei Co., Ltd.) 1.66 parts by mass (F) Photopolymerization initiator 2-methyl-1 [4- (Methylthio) phenyl] -2-morpholinopropan-1-one (trade name: Irgacure 907, manufactured by BASF): 0.23 parts by mass 2-benzyl-2-dimethylamino-1- (4- Morpholinophenyl) -butanone-1 (trade name: Irgacure 369, manufactured by BASF) 0.19 parts by mass

  10.16 parts by mass of PGMEA was added to the above composition and stirred to obtain a transparent resist composition. To the obtained transparent resist composition, 5.98 parts by mass of the pigment dispersion E obtained in Production Example 2 was added to obtain a photosensitive colored resin composition which is a blue resist composition.

Examples 6-14 and Comparative Examples 5-7
The pigment dispersion E used in Example 5 is replaced with the pigment dispersions F to N obtained in Production Examples 2 to 5, and the pigment dispersions E ′ to G ′ obtained in Comparative Production Examples 2 and 3 are used. A photosensitive colored resin composition, which is a colored resist composition, was obtained in the same manner as in Example 5 except that.

Evaluation method <S / N measurement method>
<< Measurement Method of Main Peak Intensity (S) and Background Noise Intensity (N) >>
Coarse particles were removed by crushing the pigment (A) with a mortar.
(A) For filling the pigment, a standard bottomed glass sample plate having a sample filling portion etched by 2.0 mm × 2.0 mm × 0.2 mm was used. As the glass sample plate with a bottom, a glass sample plate 20 × 20 with a bottom of 0.2 manufactured by Rigaku Corporation was used.
The (A) pigment was put into the filling portion, and the (A) pigment was pressed and spread with another glass plate or the like, and uniformly filled. In order to reduce the error, the pigment surface and the glass sample plate were flush with each other.

The main peak intensity (S) and background noise intensity (N) were measured according to the measurement method and definition described above.
A schematic diagram of the spectrum showing the intensity (S) of the main peak excluding the background and the intensity (N) of the background noise excluding the background is shown in FIG.

That is, the “bottom glass sample plate in which the sample filling portion was filled with the pigment (A)” was measured with a powder X-ray diffractometer.
The X-ray diffraction spectrum uses “RINT-TTR III” manufactured by Rigaku Corporation, which is a powder X-ray diffractometer of a concentrated optical system using CuKα rays as an X-ray source, and the scanning region 2θ = It was obtained by setting 3 to 55 °, sampling width 0.02 °, scan speed 5 ° / min, diverging slit 1/4, scattering slit 1/4, and light receiving slit 0.45 mm.
The intensity (S) of the main peak and the intensity (N) of the background noise were determined after removing the background from the X-ray diffraction spectrum by the method described above.

  The calculation method and definition of “background noise intensity (N)” are as described above, and the noise-derived peak height in the scanning range 2θ = 47.5 ° to 48.0 ° is set every 0.02 °. In addition, a total of 26 points were inspected, and the average value of a total of 12 points, excluding 7 points on each of the 26 points, was designated as “background noise intensity (N)”.

As an example, the background noise intensity (N) of Example 1 using Pigment Dispersion A in which PR177 was dry-dispersed and wet-dispersed, and Comparative Example 1 using Pigment Dispersion A ′ in which PR177 was wet-dispersed as it was. Table 1 below shows actual measurement values and specific calculation methods.
In addition, Example 1 uses pigment dispersion A (S / N = 24, N = 107), and Comparative Example 1 uses pigment dispersion A ′ (S / N = 110, N = 79). ing.
The bold and italic portions in Table 1 are the total of 12 points excluding 7 points from the top and bottom of the 26 points, and are the numerical values obtained from the average values.

<Measurement of “(A) TEM Particle Size of Pigment”>
The “(A) TEM particle diameter of the pigment used in the production of the pigment dispersion, ie, (A) the particle diameter of the pigment (average particle diameter of the pigment before wet dispersion)” was measured as described above. Defined as such.
That is, as described above, a 200,000-fold magnification STEM photograph was taken, imported into the software, 100 pigments were arbitrarily selected on the photograph, each diameter (passing length) was measured, and the volume-based distribution was calculated. The 50% cumulative particle diameter by volume, that is, the volume distribution median diameter (D50) was determined, and was defined as “(A) TEM particle diameter of pigment”.
The measurement results are shown in Table 2.

<Measurement of “average dispersed particle size”>
The average particle diameter of the pigment dispersions obtained in each example and comparative example was measured. The average dispersion particle size is measured by using “Nanotrack particle size distribution analyzer UPA-EX150” manufactured by Nikkiso Co., Ltd., and the pigment dispersion is 1000 times each so that the concentration can be measured with a laser light scattering particle size distribution meter. Diluted and measured by the method described above.

<Evaluation of contrast>
In order to evaluate the performance as a color filter, each of the photosensitive colored resin compositions, which are the colored resist compositions of Examples 1 to 12 and Comparative Examples 1 to 7, has a thickness of 0.7 mm and a 10 mm × 10 mm glass substrate (NH After applying using a spin coater on Techno Glass Co., Ltd. (NA35), a hot layer was used and dried at 80 ° C. for 3 minutes to form a colored layer having a dry thickness of 2.5 μm. .

This colored layer was irradiated with 60 mJ / cm ² of ultraviolet light using an ultra-high pressure mercury lamp, post-baked at 230 ° C. for 30 minutes, and the parallel and orthogonal luminance and contrast of the obtained colored substrate were measured. did.
The brightness was measured using a contrast measuring device CT-1 manufactured by Aisaka Electric Co., Ltd. (light source: F10 lamp between cold cathodes, luminance meter: LS-100 manufactured by Konica Minolta, spectral luminance meter: CS-1000T manufactured by Konica Minolta). .
Contrast = parallel luminance (cd / m ² ) / orthogonal luminance (cd / m ² )

  Contrast results are shown, together with (A) pigment type and physical properties (crystallinity, etc.) used in the production of the pigment dispersion, (B) dispersant, time from dry dispersion to wet dispersion, particle size before and after final dispersion, etc. Table 2 shows.

As is clear from the results in Table 2 above, in the colored layers (Examples 1 to 14) obtained using the pigment dispersions A to N produced using the method for producing a pigment dispersion of the present invention, Compared with pigment dispersions A ′ to G ′ produced using the same corresponding pigment and a pigment having an S / N greater than 90, the contrast was greatly improved.
That was true for any type of pigment. In addition, the dispersant can be said to be any of the evaluated dispersants.

  Even with a pigment having an S / N of 90 or less after performing a dry dispersion treatment or the like, the TEM particle size of the pigment is not necessarily small, and the smaller the TEM particle size of the pigment, the better the dispersibility, There was no significant correlation between the TEM particle size of the pigment and the contrast of the final composition.

  The pigment dispersion produced using the method for producing a pigment dispersion of the present invention has excellent dispersibility and dispersion stability, and the liquid crystal display and organic EL obtained using the pigment dispersion of the present invention. Color displays such as displays have high contrast, high light transmittance, and high brightness displays, so various printing inks such as inkjet, gravure, offset, screen, letterpress, various paints and paints, color resists, etc. It is widely used in the fields of various resists, display fields such as liquid crystal displays and organic EL displays, and various element manufacturing fields.

(1) Main peak intensity (S)
(2) Background noise intensity (N)

Claims (13)

A method for producing a pigment dispersion containing at least (A) a pigment, (B) a dispersant, and (C) a solvent,
As the pigment (A), the intensity (S) of the main peak obtained after removing the background from the X-ray diffraction spectrum, and the intensity (N) of the background noise obtained after removing the background from the X-ray diffraction spectrum (A) The pigment (a) whose value (S / N) divided by 90 is 90 or less is contained, and is wet-dispersed, and a method for producing a pigment dispersion liquid.   The method for producing a pigment dispersion according to claim 1, wherein the dispersant (B) is a basic block type dispersant and / or a basic graft type dispersant.   The pigment dispersion according to claim 1 or 2, wherein the (A) pigment (a) having an S / N of 90 or less is obtained by subjecting the pigment (A) having an S / N greater than 90 to dry dispersion treatment. Manufacturing method.   The (A) pigment (a) having an S / N of 90 or less is obtained by dividing the S / N of the (A) pigment after the dry dispersion treatment by the S / N of the (A) pigment before the dry dispersion treatment. The method for producing a pigment dispersion according to claim 3, which is obtained by performing a dry dispersion treatment so that the obtained value is 0.5 or less.   (A) Pigment (a) having an S / N of 90 or less is obtained by carrying out the dry dispersion treatment, and the dispersant (B) and the solvent (C) are blended in succession to the dry dispersion treatment. The method for producing a pigment dispersion according to claim 3 or 4, wherein the wet dispersion is performed.   In the dry dispersion treatment container used for the dry dispersion treatment, the S / N after the dry dispersion treatment is 90 or less (A) the pigment (a) is present in the dry dispersion treatment container. The method for producing a pigment dispersion according to claim 5, wherein the (A) pigment, the (B) dispersant, and the (C) solvent are blended by performing an operation of adding a solvent. A manufacturing how the pigment dispersion, further, a manufacturing method of a pigment dispersion according to any one of claims 1 to claim 6 is contained acidic dye derivative. A manufacturing how the pigment dispersion, the acidic dye derivative, should be contained in (A) the pigment, or, formulated during the dry dispersion process the acidic dye derivative or the acid dye derivative The method for producing a pigment dispersion according to claim 7, wherein the pigment is mixed when wet-dispersed.   A pigment dispersion liquid produced by the method for producing a pigment dispersion liquid according to any one of claims 1 to 8.   A colored resin composition for a color filter, comprising the pigment dispersion according to claim 9.   The pigment dispersion according to claim 10, further comprising at least (D) an alkali-soluble resin, (E) a polymerizable polyfunctional compound, and (F) a photopolymerization initiator. Colored resin composition for color filters.   A color filter obtained by using the colored resin composition for a color filter according to claim 10 or 11.   A display device comprising the color filter according to claim 12.

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