JP2007112919A - Pigment dispersion, colorant composition and color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pigment dispersion which is fine and has excellent flow characteristics and dispersion stability, to provide a colorant composition, and to provide a color filter having high color purity and high contrast. <P>SOLUTION: This pigment dispersion comprising (A) an isoindolin-based pigment, (B) a pigment derivative obtained by introducing one or more sulfonic groups to an isoindolin-based pigment, and a solvent, is characterized in that an organic solvent is contained as the solvent component in an amount of ≥60 wt.% based on the total solvents, and the positions of absorption peaks of the pigment derivative exist in a range of 410 to 428 nm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pigment dispersion, a colorant composition, and a color filter used for a liquid crystal display.

  In order to colorize a liquid crystal display, a color filter in which pixels of three colors of R (red), G (green), and B (blue) are arranged in a line shape or a mosaic shape on a transparent substrate is used. . For example, a TFT (thin film transistor) color liquid crystal display that is widely used at present is called a backlight in which a liquid crystal is sealed between a transparent glass substrate on which a color filter is formed and a transparent glass substrate on which a TFT is formed. The light source is made up of. When light emitted from the backlight passes through the liquid crystal panel, an image is displayed by controlling the transmittance by the voltage applied to the liquid crystal. In order to obtain an image with high display quality, that is, bright and high color purity, the pigment used in each pixel is selected to match the light transmission characteristics of the backlight, and two or more pigments are toned at a certain ratio. Often used. For example, the R (red) pixel of the color filter is used by selecting two or more pigments of red, orange, and yellow and toning at a certain ratio. Similarly, the G (green) pixel is used by selecting two or more kinds of green, orange, and yellow pigments and toning them. The pigment is selected from the required chromaticity characteristics as described above. Among them, as a toning pigment for the G pixel of the high color purity color filter, since the coloring power is high, a high color purity can be obtained with a thin film. Isoindoline pigments represented by pigment yellow (PY) 139 and 185 are preferably used.

  In order to obtain the inherent chromaticity characteristics of the pigment and to obtain high transmittance and contrast, it is necessary to disperse the pigment in fine and stable particles. When the dispersion of the pigment is unstable, the pigment aggregates, so that the contrast of the pixel coating film is lowered, and consequently the display quality of the liquid crystal display is lowered. The contrast is also related to the pigment concentration in the pixel. The higher the pigment concentration, the greater the degree of depolarization. In recent years, liquid crystal displays are required to have high color purity, and as a result, the pigment concentration in the pixel becomes high, so that contrast reduction is a significant problem. In general, yellow pigments are difficult to stably disperse, but isoindoline pigments, especially PY185, are particularly poor in dispersion stability and have been a major factor in reducing contrast.

  As a method for dispersing the pigment into fine and stable particles, a surface treatment of the pigment, for example, a general rosin treatment, an acid group treatment, a basic treatment, a pigment derivative treatment, and the like have been proposed ( (See Patent Documents 1 and 2). However, it is difficult to obtain sufficient dispersion stability only by the pigment surface treatment, and various dispersants have been proposed in order to further improve the dispersion stability. For example, Patent Documents 3 and 4 propose a method of using a low molecular pigment derivative as a dispersant. A method using a polymer pigment dispersant has also been proposed. For example, Patent Documents 5 to 9 propose a polymer pigment dispersant having a basic group. However, even if these methods are used, the selected pigment cannot always be dispersed well, and even if the dispersion stability is improved, it is sufficient to obtain a high contrast required for a recent liquid crystal display. It was not a level.

Patent Documents 10 to 17 describe that a quinophthalone derivative having a polar group such as a sulfonic acid group is used as a dispersant for dispersing a pigment mixture containing a quinophthalone yellow pigment. However, the isoindoline pigment is not effective at all, and an effective dispersant for the isoindoline pigment has been desired.
JP-A-57-28162 (2nd page) JP 59-168070 (2nd page) Japanese Patent Publication No. 4-3841 (Page 2) JP 11-295515 A (page 2) JP 54-37082 A (2nd page) Japanese Patent Laid-Open No. 9-169821 (page 2) JP 2000-95992 A (second page) JP 2000-155209 A (2nd page) JP 2001-59906 A (page 2) JP 2002-121418 A (2nd page) JP 2002-121456 A (second page) JP 2002-121457 A (second page) JP 2002-121458 A (2nd page) JP 2002-121459 A (2nd page) Japanese Patent Laid-Open No. 2002-179979 (page 2) JP 2003-176424 A (second page) JP 2004-292785 A (2nd page)

  The present invention provides a pigment dispersion and a colorant composition that are fine and have excellent flow characteristics and dispersion stability, and therefore, provide a color filter that achieves both high color purity and high contrast.

  That is, the present invention is a pigment dispersion containing (A) an isoindoline pigment, (B) a pigment derivative in which a sulfonic acid group is introduced into an isoindoline pigment, and a solvent. A pigment dispersion characterized by containing 60% by weight or more in a solvent and having an absorption peak position of the pigment derivative in the range of 410 to 428 nm.

  Since the pigment dispersion and colorant composition of the present invention have finely dispersed pigments and excellent dispersion stability, color filters and liquid crystal display panels produced using the pigment dispersion have high color purity and high contrast. And has the effect of excellent visibility.

  The present invention is a pigment dispersion characterized by comprising (A) an isoindoline pigment, (B) a pigment derivative in which a sulfonic acid group is introduced into the isoindoline pigment, and an organic solvent as a main solvent. The position of the absorption peak of the pigment derivative is in the range of 410 to 428 nm.

  Here, (A) the isoindoline pigment exhibits yellow, orange, red, and brown hues, and exhibits various excellent fastness properties including weather resistance. Therefore, R (red) in a color filter for a liquid crystal display panel , And can be preferably used as a complementary pigment for G (green) pixels. In particular, isoindoline-based pigments have a strong coloring power and are suitable for use in applications requiring high color purity.

  The (A) isoindoline pigment used in the present invention is a compound having an isoindoline skeleton in which the main component of the pigment is represented by the general formula (1). The substituents represented by R1 and R2 of the compound may be the same or different, and are a cyanoacetamide residue, a barbituric acid residue and the like. Furthermore, cyanoacetamide and barbituric acid may have a substituent such as an alkyl group, an aryl group, a halogen, an alkyl, an alkoxy, an alkoxycarbonyl, an aryl group substituted with nitro, or a heteroaryl group.

  Specific examples of the (A) isoindoline pigment used in the present invention include yellow pigments PY139 and PY185, orange pigments PO66 and PO69, and red pigment PR260. When used for G pixels, PY185 is particularly preferred because of its high coloring power and excellent color tone and transmittance.

  In the present invention, (B) a pigment derivative in which a sulfonic acid group is introduced into an isoindoline pigment is (b-1) a pigment derivative in which a sulfonic acid group is introduced into the same pigment as the (A) isoindoline pigment to be used, (B-2) (A) Two types of pigment derivatives in which a sulfonic acid group is introduced into a pigment having the same chemical structure as the chemical structure of the (A) isoindoline pigment used, And (b-2) may be used alone or in combination. For example, when an isoindoline-based yellow pigment PY185 is used as the organic pigment (A), a pigment derivative in which a sulfonic acid group is introduced into PY185 as (b-1), or PY185 and a part of PY185 as (b-2) A yellow pigment PY139 having the same chemical structure may be used alone or in combination with (b-1) and (b-2), each of which is a pigment derivative having a sulfonic acid group introduced. These pigments and pigment derivatives are strongly bonded by intermolecular force, and negatively charge the surface of the fine particles. In order to further increase the bonding strength between the pigment and the pigment derivative, it is more preferable to combine the pigment and a pigment derivative having a sulfonic acid group introduced into the pigment itself. In the following description, (B) is collectively referred to as “pigment derivative having a sulfonic acid group introduced”.

  The pigment derivative having a sulfonic acid group introduced therein (B) used in the present invention is usually a mixture of compounds having 1 to 4 sulfonic acid groups introduced into one molecule. The absorption spectrum of a pigment derivative having a sulfonic acid group introduced is that the maximum absorbance exceeds 3 (the detection limit of a normal UV-visible spectrophotometer) when a pigment derivative having a sulfonic acid group introduced is mixed with ion-exchanged water. A mixed solution having a low concentration is prepared and measured in the state of this mixed solution. The pigment derivative having a sulfonic acid group introduced in the present invention preferably has an absorption peak position in the absorption spectrum of the mixed solution in the range of 410 to 428 nm. When the absorption peak position on the shortest wavelength side of the absorption spectrum is on the longer wavelength side than 428 nm, the pigments tend to aggregate. In order to reduce the aggregation of the pigment, it is more preferable to set the absorption peak position on the shortest wavelength side of the absorption spectrum to 425 nm or less.

  The absorption peak position on the shortest wavelength side of the pigment derivative having a sulfonic acid group introduced is controlled by the reaction conditions (reaction temperature, reaction solution temperature, reaction time, etc.) when the (B) pigment derivative is synthesized. It is possible. Isoindoline pigments that are raw materials, or pigments having the same chemical structure as part of the chemical structure of isoindoline pigments do not have an absorption peak in the range of 410 to 428 nm, but appropriate reaction conditions should be applied. Thus, a pigment derivative having an absorption peak in the above range can be produced. Specifically, the concentration and mixing ratio of concentrated sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, or a mixed solution thereof are appropriately adjusted, and the reaction temperature is appropriately set within a range of 0 to 150 ° C. and a reaction time of 1 to 24 hours. By changing the reaction conditions, pigment derivatives having different absorption peak positions can be produced. A pigment derivative in which the absorption peak position is shifted to the lower wavelength side can be obtained by using fuming sulfuric acid rather than concentrated sulfuric acid, or by increasing the reaction temperature and lengthening the reaction time. The method for measuring the absorption spectrum of the pigment derivative in the present invention is performed, for example, by the following method. The pigment derivative is charged into ion-exchanged water, and then a mixed solution of the pigment derivative and ion-exchanged water is prepared by a method such as applying a ball mill, a bead mill, or ultrasonic waves. As the most preferable method, ultrasonic waves are applied for an appropriate time to prepare a mixture of pigment derivative and ion-exchanged water. Next, the absorption spectrum of the mixed solution is measured using an ultraviolet-visible spectrophotometer (for example, MultiSpec-1500 manufactured by Shimadzu Corporation).

  The pigment derivative introduced with the sulfonic acid group (B) used in the present invention is synthesized, for example, by the following method. The organic pigment is added to concentrated sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, or a mixture thereof to perform a sulfonation reaction. The resulting reaction solution is diluted with water and optionally neutralized with a metal alkali aqueous solution or an amine or an aqueous solution thereof. The suspension thus obtained is filtered, washed with an aqueous washing solution, and dried.

  When neutralization is performed in the above synthesis process, a metal alkali aqueous solution or an amine or an aqueous solution thereof is used, but an amine or an aqueous solution thereof is preferably used. If a pigment dispersion for color filters, and thus a colorant composition using the same, contains a metal alkali, it may remain in the color filter pixels and elute into the liquid crystal, resulting in display defects due to liquid crystal drive inhibition. Because there is.

  As the aqueous amine solution used for neutralization, an aqueous solution of ammonia, monoethanolamine, triethanolamine, tetramethylammonium hydroxide, or the like can be used. In the present invention, various amine aqueous solutions can be used without being particularly limited to these, but the use of ammonia is preferred because of its ease of volatilization.

  In the present invention, the mixing ratio of (A) the isoindoline-based pigment and (B) the pigment derivative having a sulfonic acid group introduced is isoindoline pigment: pigment derivative having a sulfonic acid group introduced = 85 to 85 by weight. 99:15 to 1, preferably 90 to 98:10 to 2, more preferably 92 to 97: 8 to 3. If the amount of the pigment derivative is too small, the pigment dispersion stabilizing effect is not exhibited. Conversely, if the amount of the pigmented derivative is too large, the color tone may change unfavorably.

  The solvent used in the pigment dispersion of the present invention contains an organic solvent as a solvent component in an amount of 60% by weight or more in all the solvents. 80 wt% or more is preferably an organic solvent, and more preferably 95 wt% or more. The organic solvent that can be used is not particularly limited as long as it is a general organic solvent. For example, methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, (Poly) alkylene glycol ether solvents such as propylene glycol monoethyl ether and diethylene glycol monomethyl ether, or propylene glycol monoethyl ether acetate, ethyl acetoacetate, methyl-3-methoxypropionate, 3-methyl-3-methoxybutyl Aliphatic esters such as acetate, or aliphatic alcohols such as ethanol, 3-methyl-3-methoxybutanol, cyclopentanone, Ketones such as cyclohexanone can be employed.

  As will be described later, the pigment dispersion and the colorant composition of the present invention are also preferably added with a resin. As will be described later, it is particularly preferable to use an acrylic or polyimide resin as the resin. Therefore, it is preferable to use a solvent that dissolves these resins as the solvent. Specifically, in particular when the resin is a polyimide resin, in addition to the above, a solvent for dissolving the precursor polyamic acid, that is, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N Amide polar solvents such as, N-dimethylformamide, lactones such as β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone can be preferably used.

  In this invention, you may use said solvent individually or in mixture of 2 or more types. Mixing with a solvent other than the above is also preferably used.

The pigment dispersion of the present invention contains (A) an isoindoline-based pigment, (B) a pigment derivative having a sulfonic acid group introduced therein, and (C) an organic solvent as essential components. Further, pigments other than isoindoline pigments for toning, pigment derivatives other than isoindoline pigments for improving dispersion stability, polymer dispersants, resins, and the like may be included.

  The pigment other than the isoindoline pigment that can be used in the present invention is not particularly limited. However, in view of the fact that the isoindoline pigment is often used as a complementary color pigment for R and G pixels of a color filter, R It is preferable to use a red or orange pigment that is the main pigment of the pixel, a green pigment that is the main pigment of the G pixel, or another yellow pigment that is a complementary color of the R or G pixel.

  Examples of red pigments include pigment red (hereinafter abbreviated as PR) 9, 48, 97, 122, 123, 144, 149, 166, 168, 177, 179, 180, 192, 209, 215, 216, 217, 220. 223, 224, 226, 227, 228, 240, 254, etc. can be used.

  Examples of the orange pigment include pigment orange (hereinafter abbreviated as PO) 13, 36, 38, 43, 51, 55, 59, 61, 64, 65, 71, and the like.

Examples of green pigments include pigment green (hereinafter abbreviated as PG) 7, 10, 36, and the like.
Examples of yellow pigments include pigment yellow (hereinafter abbreviated as PY) 12, 13, 17, 20, 24, 83, 86, 93, 95, 109, 110, 117, 125, 129, 137, 138, 147, 148, 150, 153, 154, 166, 168, etc. can be used. In addition, the said pigment may use what was surface-treated, such as a rosin process, an acidic group process, a basic process, and a pigment derivative process, as needed.

  In the present invention, an isoindoline pigment and other pigments can be used alone or in combination of two or more. In particular, when used for G pixels, a formulation using PY185 as an isoindoline-based pigment and PG7 and PG36 as green pigments is preferable in that the color purity can be increased with a thinner film. More preferably, a formulation in which PY138 is further combined, that is, a PG7 / PG36 / PY138 / PY185 mixed system is preferable in that both high color purity, high contrast, and high transmittance can be achieved. In the case of the PG7 / PG36 / PY138 / PY185 mixed system, the preferable mixing ratio is 30 to 55/30 to 5/15 to 35/25 to 5, more preferably 35 to 55/25 to 5/18 to 32/22. ~ 8. The mixing ratio is appropriately adjusted depending on the required color tone.

  Further, in the present invention, in order to stabilize the dispersion of the pigment, in addition to the (B) pigment derivative having a sulfonic acid group introduced, a low molecular dispersant such as an intermediate of the pigment used, a derivative, an intermediate of the dye, or a derivative. It is also preferable to use

  In the pigment dispersion of the present invention, a polymer dispersant can be added as another component. By adding a polymer dispersant, further improvement in dispersion stability can be expected. The addition of the polymer dispersant is particularly effective when the pigment dispersion and the colorant composition of the present invention are acrylic resins. The polymer dispersant is used at the time of pigment dispersion or after the pigment dispersion step. As the polymer dispersant that can be used, those having a basic group in the structure thereof are preferable. Examples of commercially available products include “Solsperse” (Avicia), “EFKA” (Efka), “Ajisper”. (Ajinomoto Fine Techno Co., Ltd.), “BYK” (Bic Chemie Co., Ltd.) and the like can be preferably used. In particular, “Solsperse” 24000, “EFKA” 4300, 4330, 4340, “Ajisper” PB821, PB822, “BYK” 161-163, 2000, 2001 are preferred because of their high dispersion stabilizing effect, and in particular, acrylic having a block structure. “BYK” 2000, 2001, which is a system dispersant, is preferable because of its excellent ability to adsorb to pigments.

  The addition amount of the polymer dispersant used in the present invention is not particularly limited, but is preferably 2 to 100 parts by weight, more preferably 10 to 50 parts by weight with respect to 100 parts by weight of the pigment. is there. If the addition amount of the polymer dispersant is less than 2 parts by weight, good pigment dispersion stability cannot be obtained, and if it is more than 100 parts by weight, the developability may be poor.

  It is also preferable to add a resin other than the polymer dispersant to the pigment dispersion of the present invention in that the dispersion stability can be further improved. Although there is no limitation in particular as a kind of resin, it is preferable that it is the same kind as resin used for the coloring agent composition mentioned later from a compatible point, and the acrylic resin and polyamic acid resin mentioned later can be used preferably.

  The concentration of the pigment in the pigment dispersion of the present invention is preferably in the range of 4 to 90 parts by weight, more preferably 5 to 18 parts by weight when the entire pigment dispersion is 100 parts by weight.

  The pigment dispersion method in the pigment dispersion of the present invention is not particularly limited, and various methods such as a sand mill, a ball mill, a bead mill, a three roll mill, and a high speed impact mill are employed. In dispersion using media, zirconia beads, alumina beads, glass beads, and the like can be used.

  The dispersion stability of the pigment dispersion of the present invention can be evaluated by measuring the Casson yield value of the pigment dispersion. The smaller the Casson yield value, the less agglomeration of particles in the particle dispersion. In the present invention, the Casson yield value of the pigment dispersion is preferably 1 × 10 −3 Pa or less.

Next, the colorant composition of the present invention will be described.
The resin of the colorant composition of the present invention is not particularly limited, and resins usually used for color filters, that is, resins such as acrylic, epoxy, or polyamic acid can be preferably used. Depending on the resin used, it can be non-photosensitive or photosensitive, and can be appropriately selected according to the color filter manufacturing process.

  Hereinafter, the case where polyamic acid is used as a typical example of a resin used for a non-photosensitive colorant composition and an acrylic resin is used as a typical example of a resin used for a photosensitive colorant composition will be described in detail. .

  A polyamic acid can be obtained by reacting a tetracarboxylic dianhydride and a diamine. In the synthesis of the polyamic acid in the present invention, for example, an aliphatic or alicyclic one can be used as the tetracarboxylic dianhydride, and specific examples thereof include 1,2,3,4. -Cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,5-cyclopentanetetracarboxylic dianhydride, 1,2,4,5 -Bicyclohexene tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-C] furan-1,3-dione and the like. Further, when an aromatic material is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained. As a specific example, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid Dianhydride, pyromellitic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 4,4 ′ -Oxydiphthalic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3,3 ", 4,4"- Examples include paraterphenyl tetracarboxylic dianhydride and 3,3 ″, 4,4 ″ -metaterphenyl tetracarboxylic dianhydride. Further, when a fluorine-based tetracarboxylic dianhydride is used, a polyamic acid that can be converted into a film having good transparency in the short wavelength region can be obtained. As a specific example, 4,4′- (Hexafluoroisopropylidene) diphthalic anhydride and the like. In the present invention, tetracarboxylic dianhydrides can be used alone or in combination of two or more without being limited thereto.

  In the synthesis of the polyamic acid in the present invention, for example, an aliphatic or alicyclic diamine can be used as the diamine, and specific examples thereof include ethylenediamine, 1,3-diaminocyclohexane, 1 4,4-diaminocyclohexane, 4,4′-diamino-3,3′-dimethyldicyclohexylmethane, 4,4′-diamino-3,3′-dimethyldicyclohexyl, and the like. In addition, when an aromatic diamine is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained. Specific examples thereof include 4,4′-diaminodiphenyl ether and 3,4′-diamino. Diphenyl ether, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfide, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, benzidine, 3,3′-dimethylbenzidine, 3,3′-dimethoxybenzidine, o-tolidine, 4, 4 "-diaminoterphenyl, 1,5-diaminonaphthalene, 3,3 ' Dimethyl-4,4′-diaminodiphenylmethane, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-amino Phenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, etc. When a fluorinated diamine is used, A polyamic acid that can be converted into a film having good transparency in the short wavelength region can be obtained. Specific examples thereof include 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane and the like. Is mentioned.

  Moreover, when siloxane diamine is used as a part of diamine, the adhesiveness with an inorganic substrate can be made favorable. Siloxane diamine is usually used in an amount of 1 to 20 mol% in the total diamine. If the amount of siloxane diamine is too small, the effect of improving adhesiveness is not exhibited, and if it is too large, the heat resistance tends to decrease. Specific examples of the siloxane diamine include bis-3- (aminopropyl) tetramethylsiloxane. The present invention is not limited to this, and one or more diamines are used.

  In general, the polyamic acid is synthesized by mixing and reacting a tetracarboxylic dianhydride and a diamine in a polar organic solvent. At this time, the polymerization degree of the resulting polyamic acid can be adjusted by the mixing ratio of diamine and tetracarboxylic dianhydride.

  In addition, there are various methods for obtaining polyamic acid, such as reacting tetracarboxylic acid dichloride and diamine in a polar organic solvent and then removing hydrochloric acid and the solvent to obtain polyamic acid. However, in the present invention, there is no limitation by the synthesis method, and the above polyamic acid can be used.

  The content of the polyamic acid in the colorant composition of the present invention is preferably 40 to 90% by mass, more preferably 45 to 80% by mass, and still more preferably 48 to 75% by mass with respect to the entire solid content. When the content of polyamic acid is less than 40% by mass, the solubility in a developer is lowered, and a problem may occur in patterning performance. If the polyamic acid content exceeds 90%, the pigment content will be relatively low, so the film thickness for obtaining a predetermined chromaticity will be too large, making it difficult to apply, or a color filter. A step on the surface becomes large, and display defects may occur.

  Next, the number of repeating structural units of the polyamic acid used in the present invention will be described. Since the mechanical properties of the polyimide film are better as the molecular weight is larger, it is desirable that the molecular weight of the polyamic acid that is the polyimide precursor is also larger. On the other hand, when pattern processing is performed on the polyimide precursor film by wet etching, if the molecular weight of the polyamic acid is too large, there is a problem that the time required for development becomes too long. Therefore, the preferable range of the number of repeating structural units is 15 to 1000, more preferably 18 to 400, and still more preferably 20 to 100. In addition, since the molecular weight of polyamic acid generally varies, the preferable range of the number of repeating structural units here is 50 mol% or more, preferably 70 mol% of the structural units of all polyamic acids in this range. As mentioned above, it means that 90 mol% or more is contained.

  An acrylic resin will be described as an example of the resin used in the photosensitive colorant composition. The acrylic resin generally has a structure containing at least an acrylic polymer, a polyfunctional monomer or oligomer, and a photopolymerization initiator in order to provide photosensitivity.

  The acrylic polymer that can be used is not particularly limited, but a copolymer of an unsaturated carboxylic acid and an ethylenically unsaturated compound can be preferably used. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides.

  These may be used alone or in combination with other copolymerizable ethylenically unsaturated compounds. Specific examples of the copolymerizable ethylenically unsaturated compound include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, isopropyl acrylate, n-propyl methacrylate, and methacrylic acid. Isopropyl, n-butyl acrylate, n-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, iso-butyl acrylate, iso-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, N-pentyl acrylate, n-pentyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, benzyl acrylate, benzyl methacrylate, and other unsaturated carboxylic acid alkyl esters, styrene, p-methyls Rene, aromatic vinyl compounds such as o-methylstyrene, m-methylstyrene and α-methylstyrene, unsaturated carboxylic acid aminoalkyl esters such as aminoethyl acrylate, unsaturated carboxylic acid glycidyl esters such as glycidyl acrylate and glycidyl methacrylate, Carboxylic acid vinyl esters such as vinyl acetate and vinyl propionate, vinyl cyanide compounds such as acrylonitrile, methacrylonitrile, and α-chloroacrylonitrile, aliphatic conjugated dienes such as 1,3-butadiene and isoprene, acryloyl groups at the terminals, Alternatively, macromonomers such as polystyrene, polymethyl acrylate, polymethyl methacrylate, polybutyl acrylate, polybutyl methacrylate, and polysilicone having a methacryloyl group And the like, but is not limited to these.

  In addition, it is preferable to use an acrylic polymer having an ethylenically unsaturated group added to the side chain, since the sensitivity during processing is improved. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, an acrylic group, and a methacryl group. As a method of adding such a side chain to an acrylic (co) polymer, when the acrylic (co) polymer has a carboxyl group or a hydroxyl group, an ethylenically unsaturated compound having a glycidyl group therein In general, an addition reaction of acrylic acid or methacrylic acid chloride is used. In addition, a compound having an ethylenically unsaturated group can be added using isocyanate. Examples of the ethylenically unsaturated compound having glycidyl group and acrylic acid or methacrylic acid chloride include glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonic acid, and glycidyl isocrotonate. Examples include ether, acrylic acid chloride, and methacrylic acid chloride.

  The content of the acrylic resin in the colorant composition of the present invention is preferably 10 to 50% by mass, more preferably 12 to 40% by mass, and still more preferably 15 to 30% by mass with respect to the entire solid content. . If the content of the acrylic resin is less than 10% by mass, the solubility in the developer is lowered, and there may be a problem in patterning performance. If the content of the acrylic resin exceeds 50% by mass, the content of other components such as a polyfunctional monomer and a photoinitiator becomes relatively small, so that sufficient sensitivity cannot be obtained and the necessary exposure amount is low. In some cases, it becomes too large, resulting in a tact-over, or the solubility in the developer is too great, and peeling during development may occur.

  Examples of the polyfunctional monomer include bisphenol A diglycidyl ether (meth) acrylate, poly (meth) acrylate carbamate, modified bisphenol A epoxy (meth) acrylate, adipic acid 1,6-hexanediol (meth) acrylate, anhydrous Phthalic acid propylene oxide (meth) acrylic acid ester, trimellitic acid diethylene glycol (meth) acrylic acid ester, rosin modified epoxy di (meth) acrylate, alkyd modified (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,6- Hexanediol di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol (Meth) acrylate, triacrylformal, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate. These can be used alone or in combination. Also, ethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxyethyl (meth) acrylate, n-butyl methacrylate, glycidyl methacrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, etc. A monofunctional monomer can also be used in combination, and a mixture of two or more of these or a mixture with other compounds is used. By selecting and combining these polyfunctional and monofunctional monomers and oligomers composed of these monomers, it is possible to control the sensitivity and processability characteristics of the paste. In particular, in order to increase the hardness, it is preferable to use a methacrylate compound rather than an acrylate compound, and in order to increase sensitivity, it is preferable to use a compound having three or more functional groups. Melamines and guanamines can also be preferably used in place of the acrylic monomers.

  The content of the polyfunctional monomer in the colorant composition of the present invention is preferably 10 to 50% by mass, more preferably 12 to 40% by mass, and still more preferably 15 to 30% by mass with respect to the entire solid content. . When the content of the acrylic resin is less than 10% by mass, the film may not be sufficiently cured with respect to light, and shape abnormality such as pattern swelling during development may occur. If the content of the polyfunctional monomer exceeds 50% by mass, the content of other components such as an acrylic resin and a photoinitiator is relatively reduced, so that sufficient sensitivity cannot be obtained and the necessary exposure amount is low. In some cases, it becomes too large, resulting in a tact-over, or the solubility in the developer is too great, and peeling during development may occur.

  There are no particular limitations on the photopolymerization initiator, and known ones can be used, such as benzophenone, N, N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2 , 2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzoin isobutyl ether, benzyldimethyl ketal, α-hydroxyisobutylphenone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholino-1-propane, t-butylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1, 4-naphthoquinone, 9,10-phenanthraquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, 2-phenylanthraquinone, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, etc. Is given. Further, inorganic photopolymerization initiators such as other acetophenone compounds, imidazole compounds, benzophenone compounds, thioxanthone compounds, phosphorus compounds, triazine compounds, and titanates can also be preferably used. Further, it is preferable to add a sensitizing aid such as p-dimethylaminobenzoic acid ester because the sensitivity can be further improved. Moreover, these photoinitiators can also be used in combination of 2 or more types.

  Although there is no limitation in particular as the addition amount of a photoinitiator, Preferably it is 1-30 mass% with respect to a coloring agent composition total solid, More preferably, it is 5-25 mass%, More preferably, it is 10-20. % By mass.

  In the colorant composition of the present invention, the solid content concentration of the resin component and the pigment is 2 to 30% by mass, preferably 3 to 25% by mass, and more preferably 5 from the viewpoints of coating properties and drying properties. Used in the range of ˜20% by mass.

  As the solvent in the colorant composition of the present invention, a solvent that dissolves the resin to be used can be preferably used. Examples of the solvent for dissolving polyamic acid include amide polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, β-propiolactone, γ-butyrolactone, γ- Examples include lactones such as valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone. In the case of acrylic resins, in addition to these, for example, ethylene glycol or propylene glycol derivatives such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, propylene glycol monoethyl ether, or propylene glycol monoethyl ether Aliphatic esters such as acetate, ethyl acetoacetate, methyl-3-methoxypropionate, 3-methyl-3-methoxybutylacetate, or aliphatic alcohols such as ethanol, 3-methyl-3-methoxybutanol, It is also possible to use ketones such as cyclopentanone and cyclohexanone.

  Moreover, as a solvent used for the coloring agent composition of this invention, it may be individual or may use the mixed solvent which combined 2 or more types of solvents suitably. In the case of a mixed solvent, it is possible to use a poor solvent for the resin to be used as a secondary solvent. As a preferable solvent system, for example, when polyamic acid is used as a resin, a combination of γ-butyrolactone and 3-methyl-3-methoxybutanol is preferable. Although there is no restriction | limiting in particular in the coloring agent composition of this invention, It is preferable to use the above organic solvents as a main component like the case of the said pigment dispersion liquid. Here, the main component means that 50 wt% or more, more preferably 80 wt% or more, more preferably 95 wt% or more of the total solvent is an organic solvent instead of water.

  A surfactant may be added to the colorant composition of the present invention for the purpose of improving the coating property and the drying property of the colored film. The addition amount of the surfactant is usually 0.001 to 10% by mass, preferably 0.01 to 1% by mass of the pigment. If the addition amount is too small, the effect of improving the coatability and the drying property of the colored coating film is small, and if it is too large, the physical properties of the coating film may be poor. Specific examples of the surfactant include anionic surfactants such as ammonium lauryl sulfate and polyoxyethylene alkyl ether sulfate triethanolamine, cationic surfactants such as stearylamine acetate and lauryltrimethylammonium chloride, lauryldimethylamine oxide, Amphoteric surfactants such as lauryl carboxymethyl hydroxyethyl imidazolium betaine, nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, sorbitan monostearate, and silicones based on polydimethylsiloxane Surfactant etc. are mentioned. In the present invention, the surfactant is not limited to these, and one or more surfactants can be used. In addition to the surfactant, an adhesion improver, a curing accelerator, and the like can be added.

Hereinafter, a method for producing a color filter using the colorant composition of the present invention will be described.
The color filter usually has a structure in which RGB three-color patterns are formed on a transparent substrate on which a black matrix (BM) is formed.

  As the BM, a known material, that is, Cr, Cr oxynitride, or a resin BM in which a light shielding material such as carbon black or titanium black is dispersed in a resin can be preferably used.

  The red, green, and blue colorant compositions for forming RGB pixels are not particularly limited. For example, as in the colorant composition of the present invention described above, a main pigment and a secondary colorant are added in a resin and a solvent. It is produced by toning with a pigment system composed of a pigment. Here, the colorant composition containing (A) an isoindoline pigment of the present invention and (B) a pigment derivative into which a sulfonic acid group is introduced is mainly a red and / or green colorant composition, more preferably Applied as a green colorant composition.

  As a method of applying the colorant composition on the substrate, a method of applying to the substrate by a spin coater, bar coater, blade coater, roll coater, die coater, screen printing method, etc., a method of immersing the substrate in a solution, a solution Various methods, such as spraying on the substrate, can be used. As the substrate, a transparent substrate such as soda glass, non-alkali glass, borosilicate glass, or quartz glass, or a semiconductor substrate such as silicon or gallium arsenide is usually used, but is not particularly limited thereto. In addition, when applying a colorant composition on a substrate, if the substrate surface is treated with an adhesion aid such as a silane coupling agent, an aluminum chelating agent, or a titanium chelating agent, the adhesion between the colored coating and the substrate is improved. Can be done as needed.

  After coating the colorant composition on the transparent substrate by the method as described above, a coating film of the colorant composition is formed by air drying, heat drying, vacuum drying or the like. In the case of heat-drying, it is preferable to use an oven, a hot plate, etc., and carry out at 50-180 degreeC for 1 minute-3 hours. Next, when the colorant composition is non-photosensitive, a photoresist is applied on the coating film to form a photoresist film. In the case of photosensitivity, a photoresist is not necessary, but an oxygen blocking film may be formed if necessary. Subsequently, a mask is placed on the coating and irradiated with ultraviolet rays using an exposure apparatus. Next, the color paste coating film is etched with an alkali developer. When there is a photoresist film or an oxygen barrier film, the development or etching of these is performed at the same time, and then these are removed with a stripping solution.

  Although it does not specifically limit as an alkaline substance used for the alkali developing solution used for this invention, For example, inorganic alkalis, such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, etc. Primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-propylamine, tertiary amines such as triethylamine and methyldiethylamine, and tetramethylammonium hydroxide (TMAH). Tetraalkylammonium hydroxides, quaternary ammonium salts such as choline, triethanolamine, diethanolamine, monoethanolamine, dimethylaminoethanol, diethylaminoethanol and other alcohol amines, pyrrole, piperidy , 1,8-diazabicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo [4,3,0] -5-nonane, organic alkalis such as cyclic amines such as morpholine. Depending on development conditions and coating film conditions, the inorganic alkali is preferably potassium hydroxide or sodium carbonate, and the organic alkali is a hydroxyl-containing organic amine such as a tetraalkylammonium hydroxide or an alcoholamine. More specifically, diethylaminoethanol, dimethylaminoethanol, and TMAH are particularly preferable because of excellent permeability to the etching film. Further, a water-soluble organic solvent such as ethanol, γ-butyrolactone, dimethylformamide, N-methyl-2-pyrrolidone may be appropriately added to the above alkaline developer.

  The resulting coating pattern of the colorant composition becomes a color filter patterned by heat treatment thereafter. The heat treatment is usually performed in air, in a nitrogen atmosphere, or in a vacuum at a temperature of 150 to 350 ° C., preferably 180 to 300 ° C., for 0.5 to 5 hours continuously or stepwise. Done. By this heating step, the polyimide precursor is converted into polyimide, and the photosensitive acrylic resin is cured.

  When the patterning process as described above is sequentially performed for each color such as R, G, and B, a color filter for a liquid crystal display device can be produced. Here, the patterning order of each color is not limited. In the present invention, in a color filter in which pixels of one color or a plurality of colors are provided in a pattern, the pixels have a colored layer, and at least one color of the colored layers is the above-described (A) isoindoline pigment. And (B) a liquid crystal display having high color purity, transmittance, and contrast ratio can be obtained by forming the colorant composition containing a pigment derivative having a sulfonic acid group introduced therein.

  Hereinafter, although this invention is demonstrated in more detail using a preferable embodiment, the efficacy of this invention is not restrict | limited at all by the embodiment used.

  The pigment derivatives, pigment dispersions, colorant compositions, and color filters in the examples were evaluated by the following methods.

<Measurement method>
A. Measurement of Absorption Spectra of Pigment Derivative A mixture liquid is prepared by putting a pigment derivative into ion-exchanged water and applying ultrasonic waves, and 400 using an ultraviolet-visible spectrophotometer (MultiSpec-1500 manufactured by Shimadzu Corporation). The absorption spectrum at ˜800 nm was measured. B. Measurement of Viscosity and Yield Value of Pigment Dispersion Using a cone-and-plate viscometer (RE100L manufactured by Toki Sangyo Co., Ltd.), the viscosity at three different shear rates was measured and determined by using the Casson equation. The storage stability of the pigment dispersion was evaluated from the obtained yield value. When the yield value is 1 × 10 −3 Pa or less, it can be considered that the dispersion stability is good.

C. Chromaticity The chromaticity coordinates (x, y) and Y in the XYZ color system in the C light source of the colorant composition coating film are measured using a microspectrophotometer “MCPD-2000” manufactured by Otsuka Electronics Co., Ltd. did.

D. Film thickness The film thickness of the coating film of the colorant composition was measured using a surface step meter “Surfcom 1400D” manufactured by Tokyo Seimitsu Co., Ltd. In addition, when the film thickness of a coloring composition coating film is compared by the same chromaticity, it is so preferable that the smaller the film thickness, the higher the color purity can be achieved with a thin film and the smaller the surface step.

E. Contrast ratio measurement A coating film formed by applying a colorant composition on a glass substrate is prepared and placed between a polarizer and an analyzer so that the film surface falls within the entire measurement area. The measurement was performed by measuring the light transmittance (I1) when parallel and the ratio (I1 / I2) of the light transmittance (I2) when the polarizer and the analyzer were orthogonal. A polarizing film “NPF-G1220DUN” manufactured by Nitto Denko Corporation was used for the polarizer and the analyzer. As a light source, “FL8A-EX / 70” manufactured by Meidaku System Co., Ltd., which is a backlight unit using a hot cathode tube, was used. The brightness of light transmitted through two polarizing films with a color filter substrate inserted between them is measured using a color luminance meter, Topcon Co., Ltd. “BM-5A”, with a visual field of 1 °. The ratio was determined. When the contrast ratio is 600 or more, it is necessary and sufficient and can be regarded as good.

Example 1
A. Synthesis of Pigment Derivative 60 g of PY185 (“Pariotor Yellow” (trade name) D1155, manufactured by BSF) was added to 780 g of fuming sulfuric acid (28% SO3) at 90 ° C. with stirring. After stirring for 3 hours, the mixture was poured into 1500 g of ice water. After standing for 30 minutes, the resulting suspension was filtered, and the resulting product was washed with 300 ml of pure water. The product was put into 2000 ml of pure water, an aqueous ammonia solution was added until the pH reached 7 or more with an aqueous ammonia solution, neutralized, and then filtered. The obtained wet crystals were washed with pure water and then dried at 80 ° C. The operations obtained by drying, washing with pure water, filtering and drying were repeated 10 times to obtain 62 g of PY185 sulfonic acid group-containing derivative YS-A. When the absorption spectrum of YS-A was measured by the method described above, an absorption spectrum was present at 421 nm.

Next, YS-A and ion-exchanged water were mixed to prepare a slurry containing sulfate ions. The prepared slurry was dialyzed using a PMMA dialysis module ("Filtizer" (trade name) B3-20A manufactured by Toray Industries, Inc.) to obtain purified PY185 derivative YS-Ad.
B. Synthesis of polyamic acid 95.1 g of 4,4′-diaminodiphenyl ether and 6.2 g of bis (3-aminopropyl) tetramethyldisiloxane were charged with 525 g of γ-butyrolactone and 220 g of N-methyl-2-pyrrolidone. 144.1 g of 4,4′-biphenyltetracarboxylic dianhydride was added and reacted at 70 ° C. for 3 hours, then 3.0 g of phthalic anhydride was added, and further reacted at 70 ° C. for 2 hours. A weight% polyamic acid solution (PAA-1) was obtained.

C. Synthesis of Polymer Dispersant 161.3 g of 4,4′-diaminobenzanilide, 176.7 g of 3,3′-diaminodiphenylsulfone, and 18.6 g of bis (3-aminopropyl) tetramethyldisiloxane, 2667 g of γ-butyrolactone, Charged together with 527 g of N-methyl-2-pyrrolidone, 439.1 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, reacted at 70 ° C. for 3 hours, and then phthalic anhydride. 2 g was added and further reacted at 70 ° C. for 2 hours to obtain a 20 wt% polyamic acid solution (PD-1).

D. Preparation of Pigment Dispersion Pigment Green PG7 43.20 g (40 wt% of the entire pigment), Pigment Green PG36 21.60 g (20 wt% of the entire pigment), Pigment Yellow PY138 32.40 g (30 wt% of the entire pigment), Pigment Yellow PY185 10.48 g (9.7 wt% of the entire pigment), 0.32 g of PY185 derivative YS-Ad (0.3 wt% of the entire pigment, 3 wt% based on the total amount of PY185 and YS-Ad) and a polymer dispersant (PD -1) 60 g and 832 g of γ-butyrolactone were mixed and stirred with a homodisper to prepare a slurry. The beaker containing the slurry was connected with a circulation type bead mill disperser ("Dynomill" KDL-A manufactured by Willy et Bacofen) and a tube, and zirconia beads having a diameter of 0.3 mm were used as a medium at 3200 rpm for 3 hours. Dispersion treatment was performed to obtain a pigment dispersion. The pigment composition ratio, viscosity, and yield value of this pigment dispersion are shown in the table.

E. Preparation of Colorant Composition In 587.3 g of the pigment dispersion prepared in D, 131.56 g of the polymer solution (PAA-1) was added 151.43 g of γ-butyrolactone and 129.64 g of 3-methoxy-3-methyl-1-butanol. The diluted solution was added and mixed, and a surfactant “BYK361” manufactured by bic chemie was added to a total solid content of 1000 ppm to obtain a green colorant composition. The pigment / polymer ratio (weight ratio) of this green colorant composition is 50/50.

F. Production of Color Filter The green colorant composition was applied onto a transparent glass substrate using a spinner, and then heat-treated in a hot air oven at 120 ° C. for 10 minutes to obtain a green colorant composition coating film. The red colorant composition was applied by adjusting the spinner rotation speed so that the chromaticity of the pattern was y = 0.600 with a C light source. Subsequently, a positive photoresist (“OFPR-800” manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied thereon and dried at 90 ° C. for 10 minutes. Using a UV exposure machine “PLA-501F” manufactured by Canon Inc., exposure was performed at 60 mJ / cm 2 (UV intensity of 365 nm) through a chromium photomask. After the exposure, the film was immersed in a developer composed of a 2.25% aqueous solution of tetramethylammonium hydroxide, and development of the photoresist and etching of the colored coating film of the polyimide precursor were simultaneously performed. The photoresist layer that became unnecessary after etching was stripped with methyl cellosolve acetate. Furthermore, the colored coating film of the polyimide precursor was heat-treated at 270 ° C. for 30 minutes to convert to polyimide. A green color filter was formed as described above. The table shows the chromaticity, contrast ratio, and film thickness of the obtained color filter with a C light source.

Example 2
Except that the reaction temperature was 80 ° C., the sulfonation reaction and purification were performed in the same manner as in Example 1 to obtain 58 g of PY185 sulfonated derivative YS-Bd. When the absorption spectrum of YS-Bd was measured by the method described above, an absorption spectrum was present at 423 nm.

A green pigment dispersion, a colorant composition, and a color filter were produced in the same manner as in Example 1 except that YS-Bd was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 3
Except that the reaction temperature was 95 ° C., the sulfonation reaction and purification were performed in the same manner as in Example 1 to obtain 6 g of PY185 sulfonated derivative YS-Cd. When the absorption spectrum of YS-Cd was measured by the method described above, an absorption spectrum was present at 419 nm.

  A green pigment dispersion, a colorant composition, and a color filter were produced in the same manner as in Example 1 except that YS-Cd was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 4
Except that the reaction temperature was 60 ° C., the sulfonation reaction and purification were performed in the same manner as in Example 1 to obtain 65 g of PY185 sulfonated derivative YS-Dd. When the absorption spectrum of the PY185 sulfonated derivative YS-Dd was measured by the method described above, an absorption spectrum was present at 425 nm.

A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Dd was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 5
Except that the reaction temperature was 50 ° C., sulfonation reaction and purification were performed in the same manner as in Example 1 to obtain 66 g of PY185 sulfonated derivative YS-Ed. When the absorption spectrum was measured by the method shown above, the absorption spectrum was present at 428 nm.

A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Ed was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 6
Pigment Yellow PY185 10.27 g (9.5 wt% of the entire pigment), 0.53 g of PY185 derivative YS-Ad (0.5 wt% of the entire pigment, 5 wt% based on the total amount of PY185 and YS-Ad) A green pigment dispersion, a colorant composition, and a color filter were produced in the same manner as in Example 1 except for the above.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 7
60 g of PY139 sulfone was obtained in the same manner as in Example 1 except that PY139 (“Irgafore Yellow” (trade name) 2R-CF manufactured by Ciba Specialty Chemicals) was used instead of PY185. The derivative YS-Gd was obtained. When the absorption spectrum was measured by the method shown above, the absorption spectrum was present at 423 nm.

  A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Id was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Comparative Example 1
Except that the reaction temperature was 30 ° C., the sulfonation reaction and purification were performed in the same manner as in Example 1 to obtain 66 g of PY185 sulfonated derivative YS-Fd. When the absorption spectrum was measured by the method described above, an absorption spectrum was present at 429 nm, but no absorption spectrum was present at 410 to 428 nm.

A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Fd was used as the pigment derivative. The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Comparative Example 2
A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that 10.80 g of pigment yellow PY185 (10 wt% of the entire pigment) was added without adding the pigment derivative. In this case, Pigment Yellow PY185 did not have an absorption spectrum at 410 to 428 nm, and had an absorption spectrum at 430 nm (see FIG. 2).

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Comparative Example 3
60 g of PY74 (“SHIKO” (trade name) Yellow FR1252 manufactured by BASF), which is a monoazo pigment, was added to 780 g of 98% concentrated sulfuric acid while stirring at room temperature. After stirring for 5 hours, the mixture was added to 1500 g of ice water. The product was put into pure 2000 ml, neutralized (added aqueous ammonia solution until the pH reached 7 or more), and then filtered. The obtained wet crystals were washed with pure water and then dried at 80 ° C. Operations obtained by drying, washing with pure water, filtering, and drying were repeated 10 times to obtain 63 g of PY74 sulfonic acid group-containing derivative YS-G. Next, dialysis was performed in the same manner as in Example 1 to obtain purified PY74 derivative YS-Gd.

  A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Gd was used as the pigment derivative.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Comparative Example 4
While stirring at 25 ° C., 60 g of PY138 (“Pariol” (trade name) Yellow D0960, manufactured by BASF), which is a quinophthalone pigment, was added to 780 g of fuming sulfuric acid (28% SO 3). After stirring for 3 hours, the mixture was added to 1500 g of ice water. The product was put into pure 2000 ml, neutralized (added aqueous ammonia solution until the pH reached 7 or more), and then filtered. The obtained wet crystals were washed with pure water and then dried at 80 ° C. Operations obtained by drying, washing with pure water, filtering, and drying were repeated 10 times to obtain 63 g of a PY138 sulfonic acid group-containing derivative YS-G. Next, dialysis was performed in the same manner as in Example 1 to obtain purified PY138 derivative YS-Hd.

A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Hd was used as the pigment derivative.
The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 8
Pigment Green PG7 27.00 g (25 wt% of the entire pigment), Pigment Green PG36 48.60 g (45 wt% of the entire pigment), Pigment Yellow PY138 23.76 g (22 wt% of the entire pigment), Pigment Yellow PY185 8. Example 1 except that 38 g (7.76 wt% of the whole pigment) and 0.26 g of PY185 derivative YS-Ad (0.24 wt% of the whole pigment, 3 wt% based on the total amount of PY185 and YS-Ad) were used. A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as described above.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 9
Pigment Green PG36 86.40 g (80 wt% of the entire pigment), Pigment Yellow PY138 15.12 g (14 wt% of the entire pigment), Pigment Yellow PY185 6.29 g (5.82 wt% of the entire pigment), PY185 derivative YS -Green pigment dispersion and colorant composition in the same manner as in Example 1 except that 0.19 g of Ad (0.18 wt% of the total pigment, 3 wt% with respect to the total amount of PY185 and YS-Ad) was used. A color filter was prepared.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 10
Pigment Green PG7 59.40 g (55 wt% of the entire pigment), Pigment Yellow PY138 33.48 g (31 wt% of the entire pigment), Pigment Yellow PY185 14.67 g (13.58 wt% of the entire pigment), PY185 derivative YS A green pigment dispersion and a colorant composition in the same manner as in Example 1 except that -Ad 0.45 g (0.42 wt% of the total pigment, 14 wt% based on the total amount of PY185 and YS-Ad) was used. A color filter was prepared.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 11
Pigment Green PG7 49.68 g (46 wt% of the entire pigment), Pigment Green PG36 33.48 g (31 wt% of the entire pigment), Pigment Yellow PY185 24.10 g (30.07 wt% of the entire pigment), PY185 derivative YS A green pigment dispersion and a colorant composition in the same manner as in Example 1 except that -Ad 0.75 g (0.93 wt% of the entire pigment, 31 wt% with respect to the total amount of PY185 and YS-Ad) was used. A color filter was prepared.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table.

Example 12
G. Preparation of Acrylic Polymer Pigment Dispersion Pigment Green PG7 48.00 g (40 wt% of the entire pigment), Pigment Green PG36 24.00 g (20 wt% of the entire pigment), Pigment Yellow PY138 36.00 g (30 wt% of the entire pigment), Pigment Yellow PY185 11.64 g (9.7 wt% of the entire pigment), 0.36 g of PY185 derivative YS-Ad (0.3 wt% of the entire pigment, 3 wt% based on the total amount of PY185 and YS-Ad) and a dispersant 102.86 g of 35% propylene glycol monomethyl ether acetate (PGMEA) solution of “Ajisper” PB821 manufactured by Ajinomoto Fine Techno Co., Ltd. and 80.00 g of “Cyclomer” ACA250 (45 wt% solution) manufactured by Daicel Chemical as an acrylic polymer Mixing the MEA 697.14g, to prepare a slurry and stirred in a homodisper. The beaker containing the slurry was connected with a circulation type bead mill disperser ("Dynomill" KDL-A manufactured by Willy et Bacofen) and a tube, and zirconia beads having a diameter of 0.3 mm were used as a medium at 3200 rpm for 3 hours. Dispersion treatment was performed to obtain a pigment dispersion. The pigment composition ratio, viscosity, and yield value of this pigment dispersion are shown in the table.

H. Preparation of photosensitive green colorant composition To 720.59 g of pigment dispersion obtained in G, 9.16 g of acrylic polymer “Cyclomer” ACA250 (45 wt% solution) manufactured by Daicel Chemical Industries, polyfunctional monomer “Kayarad” manufactured by Nippon Kayaku DPHA 30.06 g, Ciba Specialty Chemicals photoinitiator “Irgacure” 907 18.04 g, Nippon Kayaku sensitizer “Kayacure” DETX-S 9.02 g diluted with propylene glycol monomethyl ether acetate 212.72 g 279.41 g in total were added and mixed, and a surfactant “BYK333” manufactured by bic chemie was added to a total solid content of 2000 ppm to obtain a photosensitive green colorant composition using an acrylic resin. The pigment / resin ratio (weight ratio) of this green colorant composition is 50/50.

I. Production of Color Filter The green colorant composition was coated on a transparent glass substrate using a spinner, and then heat-treated in a hot air oven at 90 ° C. for 10 minutes to obtain a green colorant composition coating film. The green colorant composition was applied by adjusting the spinner rotation speed so that the chromaticity of the pattern was y = 0.600 with a C light source. Next, a predetermined area is exposed through a negative mask, and “Emulgen” A-60 (HLB12.8, polyoxyethylene derivative) as a nonionic surfactant is added to a 0.04% aqueous potassium hydroxide solution (manufactured by Kao Corporation). ) Was developed by immersing with an alkali developer added at 0.1% by mass with respect to the total amount of the developer for 90 seconds, followed by washing with pure water to obtain a patterned substrate. The obtained patterned substrate was held in a hot air oven at 220 ° C. for 30 minutes to cure the acrylic resin. A green color filter was prepared as described above. The table shows the chromaticity, contrast ratio, and film thickness of the obtained color filter with a C light source.

Comparative Example 5
A green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 12 except that 12.00 g of pigment yellow PY185 (10 wt% of the entire pigment) was added without adding the pigment derivative.

  The pigment composition ratio, viscosity, yield value of the pigment dispersion, chromaticity with a C light source of the color filter, contrast ratio, and film thickness are shown in the table. In this case, Pigment Yellow PY185 did not have an absorption spectrum at 410 to 428 nm, and had an absorption spectrum at 430 nm (see FIG. 2).

  The evaluation results of the pigment dispersions and color filters obtained in Examples 1 to 12 and Comparative Examples 1 to 5 are shown in the table together with the type of pigment derivative, the shortest peak wavelength, and the addition amount.

The pigment dispersions of Examples 1 to 7 to which an isoindoline pigment derivative having a shortest peak wavelength of 428 nm or less was added had a yield value of 1 × 10 ⁻³ or less and had good dispersion stability. Further, a high color purity of y = 0.600 was realized with a thin film having a thickness of 1.10 μm or less, and a good contrast ratio was 600 or more. On the other hand, when a pigment derivative having a shortest wavelength peak larger than 428 nm is used (Comparative Example 1), when no pigment derivative is added (Comparative Example 2), when a pigment derivative that is not isoindoline-based is used (Comparative Example 3). 4), the yield value of the pigment dispersion was larger than 1 × 10 ⁻³ , suggesting that the dispersion was unstable, and the contrast ratio was smaller than 600, which was insufficient.

Example 8 is a toning system in which PG7 is reduced compared to Example 1, and Example 9 is a case in which a toning system that does not use PG7 is used. In both cases, the pigment dispersion had a yield value of 1 × 10 ⁻³ or less, good dispersion stability, and although the film thickness was slightly large, the contrast ratio showed a good value of 600 or more. . Example 10 is a toning system that does not use PG 36, and Example 11 is a case that uses a toning system that does not use PY138. In both cases, the pigment dispersion had a yield value of 1 × 10 ⁻³ or less and good dispersion stability, and although the transmittance Y was slightly low, the contrast ratio showed a good value of 600 or more.

  Example 12 and Comparative Example 5 are cases where photosensitive acrylic was used as the resin system. In Example 10 to which the isoindoline pigment derivative was added, the pigment dispersion had a yield value of 1 × 10 −3 or less and had good dispersion stability. Further, a high color purity of y = 0.600 was realized with a thin film having a thickness of 1.10 μm or less, and a good contrast ratio was 600 or more. On the other hand, in Comparative Example 5 in which no pigment derivative was added, the yield value of the pigment dispersion was larger than 1 × 10 −3, suggesting that the dispersion was unstable, and the contrast ratio was smaller than 600, which was insufficient. there were.

The chart which showed the absorption spectrum in the wavelength range of 410-500 nm of the pigment dispersant YS-Ad of Example 1. The chart which showed the absorption spectrum in the wavelength range of 410-500 nm of the pigment dispersant YS-Fd of the comparative example 2

Explanation of symbols

1: Absorption peak on the shortest wavelength side from 410 to 800 nm

Claims (6)

A pigment dispersion containing (A) an isoindoline pigment, (B) a pigment derivative having a sulfonic acid group introduced into an isoindoline pigment, and a solvent, wherein the organic solvent as a solvent component is 60 wt. % Or more, and the position of the absorption peak of the pigment derivative is in the range of 410 to 428 nm. 2. The pigment dispersion according to claim 1, wherein in the pigment derivative, the isoindoline pigment is PY139 or PY185. A colorant composition containing at least a pigment, a resin, and a solvent, wherein the colorant composition is prepared using the pigment dispersion according to claim 1. The colorant composition according to claim 3, wherein the pigment contains PG7 and PG36. The colorant composition according to claim 4, wherein the pigment further contains PY138. In a color filter having pixels composed of a colored layer provided in a desired pattern for each color with an arbitrary number of colors, the colored layer is formed by the colorant composition according to any one of claims 3 to 5. A color filter characterized by being a colored film.

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