JP5796144B1 - Pigment dispersant, pigment composition, and pigment colorant - Google Patents

Abstract

[PROBLEMS] To significantly improve the fluidity of pigment-containing inks and paints, to prevent pigment particles from agglomerating, and to prevent generation of foreign matters, and to achieve excellent gloss and sharpness. Provided is a pigment dispersant capable of producing the indicated colored article. The following general formula (1) (X is a residue of an aromatic compound or heterocyclic compound which may have a substituent (the bonding site with N = N- is an aromatic ring or a heterocyclic ring) ), N is a pigment dispersant which is a compound represented by the following formula: quaternary ammonium salt, amine salt or metal salt thereof [Selection figure] None

Description

  The present invention relates to a pigment dispersant, a pigment composition, and a pigment colorant.

  In general, it is difficult to stably mix and disperse pigments (particles) in vehicles such as paints, gravure inks and offset inks. For example, fine pigment particles once dispersed in a vehicle tend to agglomerate in the vehicle. A vehicle in which pigment particles are aggregated has a problem that its viscosity increases. In addition, when a vehicle in which aggregated pigment particles are dispersed is used, various problems such as a reduction in the coloring power of inks and paints and a reduction in the gloss of coating films are likely to occur.

  By the way, the color filter used for manufacturing a liquid crystal color display, an imaging device, etc. is manufactured by the following methods using the pigment dispersion liquid, for example. First, a pigment dispersion for a color filter (a pigment colorant for a color filter (CF)) in which three color pigments of red (R), green (G), and blue (B) are dispersed in a photosensitive resin solution, respectively. ). These CF pigment colorants are applied to a color filter substrate by spin coating to form a colored film. Next, after the colored film formed through the photomask is exposed, development is performed to pattern the colored film, and a desired pixel is formed on the substrate, whereby a color filter can be obtained.

  Examples of the pigment for producing the color filter include a green pigment, a red pigment, and a blue pigment. Examples of the green pigment include C.I. I. Commonly used are phthalocyanine greens such as CI Pigment Green (hereinafter referred to as “PG”) 36, PG7, and PG58. Examples of red pigments include C.I. I. Commonly used are diketopyrrolopyrrole reds such as Pigment Red (hereinafter referred to as “PR”) 254; anthraquinone reds such as PR177; azo reds such as PR242. Examples of the blue pigment include C.I. I. Phthalocyanine blue such as pigment blue (hereinafter referred to as “PB”) 15: 6 is common.

  Since there is a difference between the hue of these pigments and the color characteristics required for the liquid crystal display, pigments for complementary colors are used in combination. For example, for green and red pigments, C.I. I. Yellow pigments such as Pigment Yellow (hereinafter referred to as “PY”) 138, PY139, and PY150 are used in small amounts as complementary pigments. For blue pigments, C.I. I. A small amount of a violet pigment such as Pigment Violet (hereinafter referred to as “PV”) 23 is used as a complementary color pigment. In order to form a good pixel of the color filter, it is desired that the main pigment and the complementary color pigment exist uniformly in the CF pigment colorant.

  However, it is difficult to disperse the above-mentioned pigment in a dispersion medium such as a photosensitive resin liquid using a normal disperser when using a pigment in combination, and a pigment in which the dispersion state of the pigment is not good Only a dispersion may be obtained. A color filter pixel formed using a CF pigment colorant in which the pigment is not well dispersed has insufficient light transmittance, and light transmittance as a color filter pixel is insufficient. That is, the CF pigment colorant obtained by dispersing a pigment using a normal disperser may not be sufficient as a colorant for forming a pixel of a color filter.

  On the other hand, as a photosensitive resin for a photoresist, which is a pigment dispersion medium, an acrylic polymer having a high acid value is mainly used so that a colored film after exposure can be easily developed with an alkaline aqueous solution as a developer. Has been. However, the pigment colorant containing the above-mentioned pigment and an acrylic polymer having a high acid value has a problem that the pigment tends to aggregate and the viscosity tends to increase. Moreover, since the aggregation of the pigment proceeds with time and the viscosity increases, there is a problem that the storage stability is low. Furthermore, when a color filter is manufactured using a pigment colorant having a high viscosity or agglomerating pigments and exhibiting a thixotropic viscosity, the central portion of the colored film before exposure may rise. For this reason, there arises a problem that unevenness of hue or density difference occurs between the pixel located in the central portion of the substrate and the pixel located in the peripheral portion. This problem becomes more prominent when an attempt is made to produce a color filter having a larger screen.

  Therefore, the CF pigment colorant (photoresist) contains a pigment at a high concentration, but has a good dispersion state in the photosensitive resin as a dispersion medium of the pigment, and a general ordinary dry paint or baking paint. It is required to have a low viscosity as compared with the above. In general, even when the pigment concentration is 5 to 20% by mass, the pigment is not aggregated, the viscosity is about 5 to 20 mPa · s, and the storage stability is required to be good.

  In order to satisfy the above requirements, conventionally, a method of adding a pigment derivative as a pigment dispersant, a method of treating a pigment with a pigment derivative, and the like have been proposed. Specifically, when a diketopyrrolopyrrole red such as PR254 is used as a pigment, it has been proposed to use a substituted derivative of diketopyrrolopyrrole as a pigment dispersant. Further, when an anthraquinone red such as PR177 is used as a pigment, it has been proposed to use a substituted derivative of anthraquinone as a pigment dispersant (for example, see Patent Documents 1 to 3).

JP 2001-240780 A JP 2001-174616 A JP 2009-029886 A

  In recent years, there is a desire to further improve the performance of color filters. Specifically, it is required to further improve the transparency of the colored pixels, increase the contrast of the transmitted light of the colored pixels, or increase the pigment concentration of the colored pixels. However, it has been difficult to obtain a pigment colorant that can produce a color filter that satisfies the above-described performance with the conventional techniques proposed in Patent Documents 1 to 3 and the like. Furthermore, since the pigment colorant obtained by the conventional technique is not limited to the color filter, foreign matter may be generated in the formed coating film (colored film), and hence improvement is desired.

  The present invention has been made in view of such problems of the prior art, and the problem is that the fluidity of pigment-containing inks and paints can be remarkably improved, and An object of the present invention is to provide a pigment dispersant that can prevent the aggregation of particles and can produce a colored article exhibiting excellent gloss and sharpness while preventing the generation of foreign matters. Moreover, the place made into the subject of this invention is providing the pigment composition and pigment colorant which are obtained using the said pigment dispersant.

That is, according to the present invention, the following pigment dispersant is provided.
[1] A pigment dispersant which is a compound represented by any one of the following formulas (A) to (F) .

Moreover, according to this invention, the pigment composition shown below is provided.
[2] A pigment composition containing a pigment and the pigment dispersant described in [1].
[3] The pigment composition according to [2], wherein the blending amount of the pigment dispersant is 0.5 to 40 parts by mass with respect to 100 parts by mass of the pigment.

Furthermore, according to the present invention, the following pigment colorants are provided.
[4] A pigment colorant containing the pigment composition according to the above [2] or [3] and a film-forming material.
[5] The pigment colorant according to the above [4], which is for image display, image recording, printing ink, writing ink, plastic, pigment printing, or paint.
[6] The pigment colorant according to [4], which is used for a color filter.

  The pigment dispersant of the present invention can remarkably improve the fluidity of pigment-containing inks and paints, can prevent pigment particles from agglomerating, and is excellent in preventing the generation of foreign matters. A colored article exhibiting gloss and sharpness can be produced. Therefore, the pigment dispersant of the present invention includes printing inks such as offset inks and gravure inks, various paints, plastics, pigment printing agents, electrophotographic dry or wet toners, ink jet recording inks, thermal transfer recording inks, and color filters. It can be suitably used for vehicles used for resists for printing, ink for writing instruments, and the like. In addition, if the pigment dispersant of the present invention is used, a pigment composition that can remarkably improve the fluidity of various paints, prevent pigment particle aggregation, and form a colored film in which the generation of foreign matters is effectively prevented. And pigment colorants can be provided. Furthermore, the pigment colorant of the present invention is less susceptible to thickening and gelation during storage, and can produce a colored product having excellent gloss and sharpness. For this reason, the pigment colorant of the present invention is particularly suitable as a pigment colorant for color filters.

<Pigment dispersant>
Hereinafter, the details of the present invention will be described with reference to preferred embodiments. One of the main features of the pigment dispersant of the present invention is that it is a compound represented by the following general formula (1), a quaternary ammonium salt of this compound, an amine salt of this compound, or a metal salt of this compound. I will. The pigment dispersant of the present invention having such characteristics has excellent affinity for various pigments, and is suitable as a pigment dispersant for dispersing various pigments regardless of organic or inorganic. Can be used for Further, since the pigment dispersant of the present invention has an excellent pigment dispersion effect, it can be used as a material for preparing pigment colorants for various uses.

  In general formula (1), X represents a residue of an aromatic compound or heterocyclic compound which may have a substituent. In addition, the coupling | bonding site | part with "N = N-" in General formula (1) is the aromatic ring of said aromatic compound, or the heterocyclic ring of said heterocyclic compound. Moreover, in general formula (1), n shows the number of 0.2-3. N in the general formula (1) means the average number of sulfonic acid groups introduced into the compound represented by the general formula (1).

  The pigment dispersant of the present invention exhibits an excellent action as a pigment dispersant even in a small amount. In addition, the pigment composition and the pigment colorant prepared using the pigment dispersant of the present invention are less prone to thickening and gelation during storage, and foreign matter is generated in the coating film formed using these. Hateful. Specific examples of the pigment dispersant of the present invention include compounds represented by the following formulas (A) to (F).

  Specific examples of the pigment dispersant of the present invention include compounds represented by the following formulas (1-1) to (1-8).

  The compound (pigment dispersant) represented by the general formula (1) can be synthesized, for example, as follows. First, an aromatic compound or heterocyclic compound having an amino group such as 1-aminoanthraquinone is diazotized by a conventional method and then coupled with 2,4-dihydroxyquinoline to obtain an intermediate. If the obtained intermediate is sulfonated by a conventional method using a known sulfonating agent such as fuming sulfuric acid, a compound (pigment dispersant) represented by the general formula (1) can be obtained. The pigment dispersant of the present invention may contain a small amount of unreacted raw material, but may contain some unreacted raw material as long as the effects of the present invention are obtained.

  Specific examples of the aromatic compound and heterocyclic compound having an amino group that can be used in the above synthesis method include aniline, toluidine (o-, m- or p-), 2,4-xylidine, and 3,4-xylidine. , P-cresidine, anisidine (o-, m- or p-), aminophenol (o-, m- or p-), anthranilic acid, p-aminobenzoic acid, nitroaniline (o-, m- or p-) ), Chloroaniline (o-, m- or p-), 2,5-dichloroaniline, 3,4-dichloroaniline, 3,5-dichloroaniline, 2,3,4-trichloroaniline, 2,4,5 -Trichloroaniline, 2,4,6-trichloroaniline, 3,4,5-trichloroaniline, 2-chloro-4-nitroaniline, 5-chloro-2-nitroaniline, 2,6-dichloro 4-nitroaniline, o-fluoroaniline, 2,4-difluoroaniline, m-trifluoromethylaniline, 2-chloro-5-trifluoromethylaniline, 2-aminothiophenol, 2-amino-5-nitrobenzonitrile 2-amino-3-bromo-5-nitrobenzonitrile, 1-naphthylamine, 3-amino-9-ethylcarbazole, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-aminothiazole, 2- Amino-5-nitrothiazole, 2-aminobenzothiazole, 2-amino-6-methoxybenzothiazole, 1-aminoanthraquinone, 2-aminoanthraquinone, 5-amino-2-benzimidazolinone, 4-aminophthalimide, 4-aminophthalimide Amino-N-methylphthalimide, o- (pheny Sulfonyl) aniline, 2-ethylsulfonyl-5-methoxyaniline, 2-ethylsulfonyl-5-trifluoromethylaniline, 4-benzylsulfonyl-o-anisidine, 3-amino-N, N-diethyl-4-methoxybenzenesulfone Amide, 3-aminobenzamide, 3-amino-4-methylbenzamide, 3-amino-4-methoxybenzamide, 4-aminobenzamide, 2-amino-4,4′-dichlorodiphenyl ether, 4-benzamide-2,5- Examples include dimethoxyaniline, 9-aminoacridine, 6-aminoindazole and the like. Of these, 1-aminoanthraquinone and 5-amino-2-benzimidazolinone are preferred.

  Examples of the amine that forms an amine salt with the sulfonic acid group in the general formula (1) include (mono, di, or tri) alkylamines, substituted or unsubstituted alkylenediamines, alkanolamines, and alkylammoniums. Examples include chloride. Of these, quaternary ammonium salts are preferred. Examples of the metal that forms a metal salt with the sulfonic acid group in the general formula (1) include, for example, alkali metals such as Li, Na, and K; and many metals such as Ca, Ba, Al, Mn, Sr, Mg, and Ni. A valent metal etc. can be mentioned.

Although the usage method in particular of the pigment dispersant of this invention is not restrict | limited, The usage method as shown below is illustrated. Whichever method is used, the desired pigment dispersion effect can be obtained.
(1) A pigment and a pigment dispersant are mixed in advance by a known method, and the obtained pigment composition is added to a vehicle or the like to disperse the pigment in the vehicle.
(2) A pigment and a pigment dispersant are separately added at a predetermined ratio to a vehicle or the like, and the pigment is dispersed in the vehicle.
(3) The pigment and the pigment dispersant are separately dispersed in a vehicle or the like, and then the obtained dispersions are mixed at a predetermined ratio to disperse the pigment in the vehicle.
(4) A pigment dispersant is added at a predetermined ratio to a dispersion obtained by dispersing the pigment in a vehicle or the like, and the pigment is dispersed in the vehicle.

  In the method of (1) to (4) above, a polymer dispersion having an ionic group (counterionic group) as a counter of an ionic group in the compound (pigment dispersant) represented by the general formula (1) It is preferable to add and disperse the agent. In particular, in the method (1) or (2), it is desirable to disperse in combination with a polymer dispersant having a counterionic group.

<Pigment composition>
The pigment composition of the present invention contains a pigment and the pigment dispersant described above. The blending amount of the pigment dispersant with respect to 100 parts by mass of the pigment is preferably 0.5 to 40 parts by mass, and more preferably 1 to 20 parts by mass. If the amount of the pigment dispersant is less than the above range, the effect of the intended dispersant may not be sufficiently obtained. On the other hand, if the amount of the pigment dispersant is larger than the above range, the effect of the dispersant will reach its peak, and no further effect can be expected. It may become. Furthermore, in paints and inks using a pigment composition containing an excessive amount of such a pigment dispersant, the physical properties of the vehicle are reduced, or the hue of the pigment varies greatly depending on the color of the pigment dispersant itself. Sometimes.

  Specific examples of pigments that can obtain an effective dispersion effect by using the pigment dispersant of the present invention include soluble / insoluble azo pigments, high molecular weight azo pigments, phthalocyanine pigments, quinacridone pigments, anthraquinone pigments, diketopyrrolopyrrole pigments. Quinophthalone pigment, methine / azomethine pigment, perylene pigment, perinone pigment, isoindolinone pigment, isoindoline pigment, metal complex pigment, and the like. Among these, particularly when used for a pigment having a hue of red, a more remarkable effect is obtained, which is preferable. As the pigment having such a red hue, PR254 which is a diketopyrrolopyrrole pigment and PR177 which is an anthraquinone pigment are preferable.

The method for producing the pigment composition of the present invention is not particularly limited. For example, the pigment composition of the present invention can be obtained by mixing a pigment and a pigment dispersant by a conventionally known method. Specific examples of the method for producing the pigment composition of the present invention include the following methods (1) to (4).
(1) A method of mixing a powder of a pigment and a powder of a pigment dispersant without using a disperser.
(2) A method of mechanically mixing the pigment and the pigment dispersant with various dispersing machines such as a kneader, a roll, an attritor, and a horizontal bead mill.
(3) A method of adding and mixing a liquid in which a pigment dispersant is dissolved or finely dispersed into an aqueous suspension or an organic solvent suspension of the pigment, and uniformly depositing the pigment dispersant on the surface of the pigment.
(4) A method in which a pigment and a pigment dispersant are dissolved in a solvent having strong dissolving power such as sulfuric acid and then co-precipitated with a poor solvent such as water.

  The properties of the pigment dispersant used for preparing the pigment composition may be any of solution, slurry, paste, and powder. The desired effect can be obtained even when any kind of pigment dispersant is used.

<Pigment colorant>
The pigment colorant of the present invention contains the pigment composition described above and a film forming material. The pigment colorant of the present invention mixes, for example, the above-described finely-divided pigment composition and a film-forming material such as a resin ((co) polymer), oligomer, or monomer selected according to the application. Can be obtained. The pigment colorant of the present invention can be used in a wide range of fields as a colorant for image display, image recording, printing ink, writing ink, plastic, pigment printing, paint and the like. In particular, it is suitable as an image display material in which the transparency of colored pixels is a problem, particularly as a pigment colorant for a color filter. Of course, the pigment colorant of the present invention is also useful as a material for image recording agents such as electrophotographic dry or wet toner, ink jet recording ink, electrodeposition recording liquid, thermal transfer recording ink, and writing instrument ink. These materials for image recording agents are used in various image recording methods such as an ink jet recording method, an electrodeposition recording method, and an electrophotographic method. By using the pigment colorant of the present invention, a material for an image recording agent capable of providing a high-quality image can be prepared by any image recording method.

  Hereinafter, further details of the pigment colorant of the present invention will be described using a color filter pigment dispersion (color filter (CF) pigment colorant) which is a pigment colorant for image display as a representative example. To prepare a color filter pigment dispersion (photoresist), first, the above-described pigment composition is added to a liquid containing a film-forming material and premixed. Next, if a dispersion treatment is performed, a pigment dispersion for a color filter can be obtained. More specifically, a pigment composition that has been uniformly ground using a dispersing machine such as a vertical medium disperser, a horizontal medium disperser, or a ball mill is added to and mixed with a liquid containing a film-forming material. Thus, a pigment dispersion for a color filter can be obtained. Further, a solution obtained by dissolving a pigment and a pigment dispersant in sulfuric acid or the like is mixed with water, and a pigment composition containing the pigment and the pigment dispersant is precipitated as a solid solution or a eutectoid and separated. After the separated pigment composition is added to and mixed with a liquid containing a film-forming material, a polymer dispersant, etc., it may be ground and dispersed using a horizontal wet medium disperser (bead mill) such as dyno mill. A pigment dispersion for a color filter can be obtained.

  The pigment colorant of the present invention may further contain a polymer dispersant. As the polymer dispersant, a basic polymer dispersant is preferable. The surface of the pigment in the pigment colorant of the present invention is treated with an acidic pigment dispersant represented by the general formula (1). For this reason, a pigment dispersion for color filters having a lower viscosity and a higher contrast can be obtained by containing a basic polymer dispersant. If an acidic polymer dispersant is contained, the pigment may aggregate and the pigment colorant may easily thicken.

  A known dispersant can be used as the polymer dispersant. Specific examples of the basic polymer dispersant are the following trade names: DISPERBYK-160, 161, 162, 163, 164, 166, 171, 182, 184, 2000. , 2001, 2070, 2150 (above, manufactured by Big Chemie); EFKA-44, 46, 47, 48, 4010, 4015, 4020, 4050, 4055, 4060, 4060 4300, 4330, 4400, 4406, 4510, 4800 (above, manufactured by BASF); SOLPERS-24000, 32550, NBZ-4204 / 10 (above, manufactured by Lubrizol); Hinoact T-6000, 7000, 8000 (above, manufactured by Kawaken Fine Chemical Co., Ltd.); Ajisper PB-821, 822, 8 3 (above, manufactured by Ajinomoto Fine-Techno Co., Inc.), and the like.

  The blending amount of the polymer dispersant is preferably 2 to 100 parts by mass, and more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the pigment. When the blending amount of the polymer dispersant is less than 2 parts by mass, it may be difficult to obtain good pigment dispersion stability. On the other hand, if the blending amount of the polymer dispersant exceeds 100 parts by mass, the developability of the formed film may be lowered.

  As a liquid containing a film forming material used for preparing a pigment dispersion for a color filter, a solution of a film forming polymer contained in a conventionally known pigment dispersion for a color filter can be used. Examples of the liquid medium used for the liquid containing the film forming material include an organic solvent, water, and a mixed liquid of an organic solvent and water. In addition, conventionally well-known additives, such as a dispersion | distribution adjuvant, a smoothing agent, an adhesive agent, can be added to the pigment dispersion liquid for color filters as needed.

  The amount of the pigment composition contained in the pigment colorant of the present invention is preferably 5 to 500 parts by mass, more preferably 50 to 250 parts by mass with respect to 100 parts by mass of the film forming material. Moreover, as a liquid containing a film-forming material, a liquid containing a photosensitive film-forming material or a liquid containing a non-photosensitive film-forming material can be appropriately selected and used depending on the application. Specific examples of the liquid containing the photosensitive film-forming material include a liquid containing a photosensitive film-forming material used for ultraviolet curable ink, electron beam curable ink, and the like. Specific examples of liquids containing non-photosensitive film-forming materials include varnishes used for printing inks such as letterpress inks, lithographic inks, gravure inks and screen inks; varnishes used for room temperature drying or baking paints; Examples thereof include varnishes used for coating and varnishes used for thermal transfer ribbons.

  The pigment dispersion for a color filter is required to have a good pigment dispersion state and a low viscosity as compared with general ordinary dry paints and baking paints while containing a pigment at a high concentration. In general, even when the pigment concentration is 5 to 20% by mass, the pigment is not aggregated, the viscosity is about 5 to 20 mPa · s, and the storage stability is required to be good. Therefore, when used for a color filter, the pigment dispersion of the present invention preferably satisfies the above viscosity condition. Preferably, the viscosity is 5 to 15 mPa · s, and the rate of increase in viscosity after standing for 1 month at 25 ° C. (after standing) is within 10%. When the viscosity increases, it becomes difficult to form a film with a certain thickness.

  Specific examples of photosensitive film forming materials include photosensitive cyclized rubber resins, photosensitive phenol resins, photosensitive polyacrylate resins, photosensitive polyamide resins, photosensitive polyimide resins, and unsaturated polyester resins. And photosensitive resins such as polyester acrylate resins, polyepoxy acrylate resins, polyurethane acrylate resins, polyether acrylate resins, and polyol acrylate resins. In addition, you may add various monomers as a reactive diluent to the liquid containing these photosensitive resins.

  If a photopolymerization initiator such as benzoin ether or benzophenone is added to a pigment colorant containing a photosensitive resin as a film-forming material and kneaded by a conventionally known method, a photocurable photosensitive pigment dispersion is obtained. be able to. Further, if a thermal polymerization initiator is used instead of the photopolymerization initiator, a thermosetting pigment dispersion can be obtained.

  On the other hand, specific examples of non-photosensitive film-forming materials include styrene- (meth) acrylic acid ester (co) polymers, soluble polyamide resins, soluble polyimide resins, soluble polyamideimide resins, and soluble polyesterimide resins. Resin, water-soluble salt of styrene-maleic acid ester copolymer, water-soluble salt of (meth) acrylic acid ester- (meth) acrylic acid copolymer, water-soluble aminopolyester resin, and water-soluble resin Mention may be made of salts.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. Hereinafter, “parts” and “%” are based on mass unless otherwise specified.

<Preparation of pigment dispersant>
Example 1
10 parts of 2,4-dihydroxyquinoline and 5 parts of sodium hydroxide were dissolved in 600 parts of water, 14 parts of 1-aminoanthraquinone were diazotized by a conventional method, and coupled at 20 to 30 ° C. for 4 hours. . After filtration and washing with water, 24 parts of intermediate were obtained by drying. After dissolving 10 parts of the intermediate obtained in 100 parts of 20% fuming sulfuric acid, the mixture was reacted at 50-60 ° C. for 5 hours. After allowing to cool, the mixture was poured into ice water, filtered, washed with water, and dried to obtain 12 parts of a yellowish brown pigment dispersant (A) represented by the following formula (A).

(Example 2)
120 parts of water was added to 50 parts of the pigment dispersant (A) paste obtained in Example 1 (amount of the pigment dispersant (A): 10 parts), and the mixture was stirred at 20 to 30 ° C. for 1 hour. After adding 14 parts of tetrabutylammonium bromide and stirring for 1 hour, filtration, washing with water and drying were performed to obtain 14 parts of a tan pigment dispersant (B) represented by the following formula (B).

(Example 3)
A yellow-green pigment represented by the following formula (C) in the same manner as in Example 2 except that 13 parts of aluminum sulfate 14-18 hydrate was used instead of 14 parts of tetrabutylammonium bromide. Dispersant (C) 10.3 parts was obtained.

Example 4
A red pigment represented by the following formula (D) in the same manner as in Example 1 except that 10 parts of 5-amino-2-benzimidazolinone was used instead of 14 parts of 1-aminoanthraquinone. 12.4 parts of dispersant (D) was obtained.

(Example 5)
In place of the paste of the pigment dispersant (A), except that 48 parts of the paste of the pigment dispersant (D) obtained in Example 4 (the amount of the pigment dispersant (D): 9 parts) was used. In the same manner as in Example 2, 13 parts of a red pigment dispersant (E) represented by the following formula (E) was obtained.

(Example 6)
In place of the paste of the pigment dispersant (A), except that 48 parts of the paste of the pigment dispersant (D) obtained in Example 4 (the amount of the pigment dispersant (D): 9 parts) was used. In the same manner as in Example 3, 9.1 parts of a red pigment dispersant (F) represented by the following formula (F) was obtained.

  Elemental analysis of CHN and mass spectrometry by MALDI (abbreviation for matrix-assisted laser desorption / ionization method) confirmed that the prepared pigment dispersants (A) to (F) had the intended composition. In addition, Table 1 shows the results of elemental analysis for the pigment dispersants (A) to (F). As shown in Table 1, values close to the calculated values (theoretical values) were obtained for any of C, H, and N elements. Further, by S analysis, a value close to the calculated value (theoretical value) in which the number of substituted sulfonic acid groups was “1” was obtained. For the pigment dispersant (A), a peak at m / z = 475 was detected by mass spectrometry. Furthermore, the purity of the pigment dispersant (A) measured using high performance liquid chromatography (Nippon Bunko Kogyo Co., Ltd .: MODEL 860-CO, YMC Co., Ltd. column: YMCPack Pro C18) was 93%. For this reason, it was confirmed that the compound of the target composition was obtained from the results of the raw materials used, elemental analysis, mass spectrometry, and high performance liquid chromatography.

<Preparation of pigment compositions (1) to (12)>
(Example 7)
100 parts of PR254 (trade name “IRGAZIN RED L3660HD”, manufactured by BASF), 5 parts of the pigment dispersant (A) obtained in Example 1, 600 parts of sodium chloride having an average particle diameter of 5 μm, and 150 parts of diethylene glycol were pressurized. We prepared a kneader with a lid. After pre-kneading until a uniformly wet lump was formed in the kneader, the pressure lid was closed, and kneading and grinding were started while pressing the contents at a pressure of 6 kg / cm ² . While controlling the cooling temperature and the amount of cooling water so that the temperature of the contents was 40 to 45 ° C., the mixture was kneaded and ground for 4 hours to obtain a ground product. The obtained ground product was put into 3,000 parts of a 2% aqueous sulfuric acid solution heated to 80 ° C., stirred for 1 hour, filtered and washed with water to remove sodium chloride and diethylene glycol. The filtration residue was dried in a hot air dryer at 80 ° C. for 24 hours to obtain a pigment composition (1).

(Examples 8 to 12)
Pigment compositions (2) to (6) were obtained in the same manner as in Example 7 except that the pigment dispersants (B) to (F) were used in place of the pigment dispersant (A).

(Example 13)
A pigment composition (7) was obtained in the same manner as in Example 7 except that PR177 (trade name “PALIOGEN RED L4039”, manufactured by BASF) was used instead of PR254.

(Examples 14 to 18)
Pigment compositions (8) to (12) were obtained in the same manner as in Example 13 except that the pigment dispersants (B) to (F) were used in place of the pigment dispersant (A).

  Table 2 shows combinations of pigments and pigment dispersants used in preparing the pigment compositions (1) to (12).

<Preparation of pigment dispersion (pigment colorant for color filter (CF))>
(Example 19)
An acrylic resin varnish having a mean molecular weight of 12,000 and a solid content of 40% obtained by copolymerizing methacrylic acid / benzyl acrylate / styrene / hydroxyl acrylate at a molar ratio of 25/50/15/10 is used. Then, a pigment dispersion was prepared according to the method shown below. 50 parts of the above acrylic resin varnish, 20 parts of the pigment composition (1), 17.4 parts of a basic polymer dispersant (trade name “DISPERBYK-2001”, manufactured by BYK Chemie, solid content 46%), and solvent As a mixture, 20 parts of propylene glycol-1-monomethyl ether-2-acetate was mixed, premixed, and then dispersed using a horizontal bead mill to obtain a CF pigment colorant (Example 19).

(Examples 20 to 30)
A CF pigment colorant (Examples 20 to 30) was obtained in the same manner as in Example 19 except that the pigment compositions (2) to (12) were used in place of the pigment composition (1). .

(Comparative Example 1)
A composition containing PR254 not treated with the pigment dispersant was obtained in the same manner as in Example 7 except that the pigment dispersant (A) was not used. Then, in place of the pigment composition (1), a CF pigment colorant (Comparative Example 1) was obtained in the same manner as in Example 19 except that the composition containing PR254 obtained above was used. It was.

(Comparative Example 2)
A pigment composition was obtained in the same manner as in Example 7 except that the pigment dispersant (G) represented by the following formula (G) described in Patent Document 1 was used instead of the pigment dispersant (A). A product (13) was obtained. A CF pigment colorant (Comparative Example 2) was obtained in the same manner as in Example 19 except that the pigment composition (13) obtained above was used instead of the pigment composition (1). It was.

(Comparative Example 3)
A composition containing PR177 not treated with the pigment dispersant was obtained in the same manner as in Example 13 except that the pigment dispersant (A) was not used. Then, in place of the pigment composition (1), a CF pigment colorant (Comparative Example 3) was obtained in the same manner as in Example 19 except that the composition containing PR177 obtained above was used. It was.

(Comparative Example 4)
Instead of the pigment dispersant (A), the pigment composition was the same as in Example 13 except that the pigment dispersant (H) represented by the following formula (H) described in Patent Document 1 was used. A product (14) was obtained. Then, in place of the pigment composition (1), a CF pigment colorant (Comparative Example 4) was obtained in the same manner as in Example 19 except that the pigment composition (14) obtained above was used. It was.

<Evaluation>
About each pigment pigment for CF of Examples 19 to 30 and Comparative Examples 1 to 4, (1) fluidity (storage stability), (2) gloss of the color development surface, (3) foreign matter in the coating film, and (4) The contrast was evaluated. Each evaluation method is shown below. The evaluation results are shown in Table 3.

(1) Fluidity (storage stability)
Using an E-type viscometer, the viscosity (mPa · s) of the CF pigment colorant immediately after preparation (initial stage) and after standing for 1 month at 25 ° C. (after standing) is measured to evaluate fluidity. Standard. The measurement conditions were temperature: room temperature (25 ° C.) and rotor rotation speed: 6 rpm. Further, “viscosity after standing / initial viscosity (%)” was calculated, and “storage stability” was evaluated according to the following criteria using the obtained calculated value.
○: “Viscosity after standing / initial viscosity” is 110% or less.

(2) Using a gloss bar coater (winding thickness: 0.45 mm) on the color development surface, the color pigment for CF was developed on a polypropylene film to form a color development surface. The gloss of the developed color surface was observed using a visual observation and a gloss meter, and “gloss of the color developed surface” was evaluated according to the following criteria. It can be determined that the higher the gloss of the color development surface, the better.
◎: Very good ○: Good ×: Bad

(3) Foreign matter in coating film A CF pigment colorant was applied to a glass substrate using a spinner, dried at 90 ° C for 2 minutes, and then heated at 270 ° C for 30 minutes to form a coating film. Using a microscope, the surface (application surface) of the formed coating film was observed at 200 times to confirm the presence or absence of foreign matter, and “foreign matter in the coating film” was evaluated according to the following criteria.
◎: No foreign matter ○: Slight foreign matter ×: Foreign matter

(4) Contrast A CF pigment colorant was applied to a glass substrate using a spinner, dried at 90 ° C. for 2 minutes, and then heated at 230 ° C. for 30 minutes to form a coating film. Further, three coating films were formed by changing the spinner speed. The brightness (brightness / dark brightness) of the coating film formed using a contrast meter (manufactured by Eye System) was measured, and the contrast (bright brightness / dark brightness) was calculated. Furthermore, the color of the coating film was measured using a spectrophotometer (trade name “U-2000A”, manufactured by Hitachi, Ltd.), and chromaticity x was measured. An approximate straight line was drawn on the graph created by plotting contrast against chromaticity x, and the contrast at chromaticity x = 0.650 was read. The contrast ratio (%) of each example and comparative example was calculated by setting the contrast of Comparative Example 2 or the contrast of Comparative Example 4 to “100%”. Then, “contrast” was evaluated according to the following criteria using the obtained calculated values.
◎: 110% or more ○: 90% or more and less than 110% ×: less than 90%

  As shown in Table 3, the CF pigment colorant of the example has a low viscosity, good storage stability, and good gloss on the color development surface compared to the CF pigment colorant of the comparative example. It can be seen that no foreign matter is generated in the coating film and the contrast is high. From the above, it is clear that the pigment dispersants of the examples have excellent effects.

  Furthermore, the pigment compositions of the examples were used in printing inks such as offset inks; various paints such as nitrocellulose lacquer and melamine alkyd paint; and colorants of synthetic resins such as vinyl chloride resins. As a result, in any case, the pigment did not aggregate and showed good dispersibility. In addition, the pigment dispersants of the examples were used for the preparation of electrophotographic dry or wet toners, ink jet recording inks, thermal transfer recording inks, writing instrument inks, and the like that have recently been particularly required to have high dispersibility. . As a result, excellent dispersibility was exhibited in all cases.

  The pigment dispersant of the present invention includes printing ink (offset ink, gravure ink, etc.), various paints, plastics, pigment printing agents, electrophotographic dry or wet toner, ink jet recording ink, thermal transfer recording ink, color filter resist. It is useful as a dispersant to be blended in ink for writing instruments and the like, and its use is expected.

Claims (6)

A pigment dispersant which is a compound represented by any of the following formulas (A) to (F) .

  A pigment composition comprising a pigment and the pigment dispersant according to claim 1.   The pigment composition according to claim 2, wherein a blending amount of the pigment dispersant is 0.5 to 40 parts by mass with respect to 100 parts by mass of the pigment.   A pigment colorant comprising the pigment composition according to claim 2 and a film-forming material.   The pigment colorant according to claim 4, which is used for image display, image recording, printing ink, writing ink, plastic, pigment printing, or paint.   The pigment colorant according to claim 4, which is used for a color filter.