JP2012036380A - Pigment dispersant and pigment composition using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a pigment dispersant suitable for the fields of paints, colored resin compositions, etc., and capable of producing a dispersion excellent in non-aggregation property, flowability and storage stability; a method for producing the same; and a pigment composition using the same.SOLUTION: The pigment dispersant is produced by reacting a hydroxyl group in a vinyl polymer (A) having three or more hydroxyl groups in a one-end region, obtained by radically polymerizing an ethylenically unsaturated monomer (b) in the presence of a compound (a) having three or more hydroxyl groups and one thiol group within a molecule, with an acid anhydride group in a carboxylic acid anhydride (c). The pigment dispersant is also produced by radically polymerizing the ethylenically unsaturated monomer (b) in the presence of a compound obtained by reacting a hydroxyl group in the compound (a) having three or more hydroxyl groups and one thiol group in a molecule with an acid anhydride group in the carboxylic acid anhydride (c).

Description

  The present invention relates to a pigment dispersant, and more specifically, a pigment dispersion capable of producing a dispersion excellent in non-aggregability, fluidity, and storage stability, which is suitable for the fields of paints and colored resin compositions. The present invention relates to an agent, a method for producing the same, and a pigment composition using the same.

  Generally, when manufacturing ink etc., it is known that it is difficult to disperse | distribute a pigment stably at high concentration, and it is known that it causes various problems with respect to a manufacturing process or the product itself. For example, dispersions containing pigments composed of fine particles often exhibit high viscosity, making it difficult to remove and transport the product from the disperser, and if bad, cause gelation during storage and use It can even be difficult. Furthermore, regarding the surface of the color-extended product, a state failure such as a decrease in gloss and a leveling failure occurs. In addition, when different types of pigments are used in combination, color unevenness due to aggregation or phenomena such as sedimentation may cause color unevenness or a significant reduction in coloring power.

Therefore, in general, a dispersant is used in order to maintain a good dispersion state. The dispersant has a structure of a site that adsorbs to the pigment and a site that has a high affinity for the solvent that is the dispersion medium, and the performance of the dispersant is determined by the balance of these two functional sites. That is, in order to develop dispersibility, both the ability of the dispersant to adsorb to the pigment and the affinity to the solvent as the dispersion medium are very important.
Various dispersants are used according to the surface condition of the pigment to be dispersed. However, when dispersing organic pigments, acidic dispersants are used for pigments having a surface that is biased toward basicity. It is common. In this case, the acidic functional group becomes the adsorption site of the pigment. Examples of the acidic functional group include carboxylic acid. In addition, a basic dispersant is used for a pigment having an acid-biased surface. When the inorganic pigment is dispersed, the site that interacts with the hydroxyl group on the inorganic surface becomes the pigment adsorbing portion. For example, a carboxylic acid that forms a hydrogen bond with a hydroxyl group on the inorganic surface can be used. Examples of the solvent affinity part include a vinyl polymer produced by radical polymerization of an ethylenically unsaturated monomer. By changing the ethylenically unsaturated monomer according to the solvent used, the affinity with the solvent is increased. Sex can be adjusted. The dispersing agent which has carboxylic acid is described in patent document 1, patent document 2, patent document 3, patent document 4, patent document 5, etc., for example.

  However, although the dispersing agents described in Patent Documents 1 to 4 have a certain degree of dispersing ability, it is necessary to increase the amount of use in order to produce a stable dispersion with low viscosity. However, increasing the amount used is not preferable in view of development in inks, paints, etc., because the resistance of the coating film may be reduced. Moreover, although the dispersing agent described in Patent Document 5 is excellent in dispersion ability and coating film resistance, since the combination of the solvent affinity part and the difference pigment adsorption part is limited, the balance is optimal depending on the application. Since the structure cannot be obtained, the dispersibility is insufficient, and the use amount is increased more than necessary, which may reduce the degree of freedom in formulating inks and paints.

JP-A-61-61623 JP-A-1-141968 Japanese Patent Laid-Open No. 2-219866 JP 11-349842 A Japanese Patent No. 4396777

  An object of this invention is to provide the dispersing agent for obtaining the pigment dispersion which is excellent in a dispersibility, fluidity | liquidity, and storage stability by the low usage-amount. Furthermore, the present invention is suitable for offset ink, gravure ink, color filter resist ink and ink jet ink, paint, colored resin composition, etc., and has dispersibility and stability excellent in non-aggregability and fluidity. An object of the present invention is to provide a pigment dispersant that can be used.

That is, the present invention provides a single terminal obtained by radical polymerization of an ethylenically unsaturated monomer (b) in the presence of a compound (a) having three or more hydroxyl groups and one thiol group in the molecule. A hydroxyl group in the vinyl polymer (A) having three or more hydroxyl groups in the region, an acid anhydride group of the carboxylic acid anhydride (c), and
It is related with the dispersing agent for pigments produced | generated by making this react.

The present invention also provides a hydroxyl group in the compound (a) having three or more hydroxyl groups and one thiol group in the molecule;
An acid anhydride group in the carboxylic acid anhydride (c);
The present invention relates to a dispersant for pigments produced by radical polymerization of an ethylenically unsaturated monomer (b) in the presence of a compound having a carboxyl group and a thiol group obtained by reacting.

  The present invention also relates to the above dispersant for pigment, wherein the carboxylic anhydride (c) is a tricarboxylic anhydride or a tetracarboxylic dianhydride.

Moreover, this invention relates to the said dispersing agent for pigments characterized by tetracarboxylic anhydride being represented by the following general formula (1) or general formula (2).
General formula (1)


[In General Formula (1), k is 1 or 2. ]
General formula (2)


[In General Formula (2), R ¹ represents a direct bond, —O—, —CO—, —COOCH ₂ CH ₂ OCO—
_{, -SO 2 -, - C (} CF 3) 2 -, wherein:


Or a group represented by the formula:


It is group represented by these. ]

Furthermore, this invention relates to the said dispersing agent for pigments characterized by a tricarboxylic acid anhydride being represented by following General formula (3).
General formula (3)


[In General Formula (3), k is 1 or 2. ]

Furthermore, this invention relates to the said dispersing agent for pigments characterized by the ethylenically unsaturated monomer (b) containing the monomer represented by following General formula (4).
General formula (4)

  Furthermore, this invention relates to the said dispersing agent for pigments whose weight average molecular weights of the vinyl polymer part formed by radically polymerizing an ethylenically unsaturated monomer are 1000-10000.

  In addition, the present invention relates to a pigment composition containing the above dispersant for pigment and the pigment (P), and a pigment dispersion obtained by dispersing the pigment composition in a varnish.

  By using the pigment dispersant of the present invention, it is possible to provide a pigment composition having dispersibility, fluidity, and storage stability that has not been obtained conventionally. Furthermore, it is suitable for offset ink, gravure ink, color filter resist ink and ink jet ink, paint, colored resin composition, etc., has excellent dispersibility and stability with excellent non-aggregation and fluidity, and high storage stability. A pigment dispersion having high stability with time can be provided.

  In general, a pigment dispersant has a structure of a part that adsorbs to a pigment and a part that has a high affinity for a solvent as a dispersion medium, and the performance of the dispersant is determined by the balance between these two parts. That is, in order to develop dispersibility, both the ability of the dispersant to adsorb to the pigment and the affinity to the solvent as the dispersion medium are very important.

  First, the pigment adsorption site of the pigment dispersant of the present invention will be described. The carboxylic anhydride (c) used in the present invention can react with a hydroxyl group to form an ester bond and leave a pendant carboxyl group that functions as a pigment adsorption site. The dispersant of the present invention is a reaction between a compound (a) having three or more hydroxyl groups and one thiol group in the molecule (hereinafter sometimes abbreviated as compound (a)) and a carboxylic acid anhydride (c). Can have at least three carboxyl groups in very close regions in the molecule. That is, by using the compound (a), a large number of carboxyl groups can be arbitrarily and efficiently introduced into the molecule, and a plurality of adjacent carboxyl groups are effective as adsorption sites for the pigment.

  Next, the solvent affinity part of the pigment dispersant of the present invention will be described. The compound (a) having three or more hydroxyl groups and one thiol group in the molecule used in the present invention is obtained by radical polymerization of the ethylenically unsaturated monomer (b) in the presence of the vinyl copolymer. A vinyl polymer (A) having three or more hydroxyl groups present in the combined part B and one terminal region can be produced.

  In this specification, vinyl polymer part B obtained by radical polymerization of an ethylenically unsaturated monomer (hereinafter sometimes abbreviated as vinyl polymer part B) means three or more hydroxyl groups and 1 It is the continuous part which does not contain the part derived from the compound (a) having two thiol groups and the carboxylic acid anhydride (c). Since the vinyl polymer portion is generated by the number of thiol groups in the molecule, at least one vinyl polymer portion derived from the compound (a) is contained in one molecule constituting the pigment dispersant of the present invention. B will be included. This vinyl polymer part B is effective as a solvent affinity part.

From the above, the dispersant of the present invention comprises a compound (a) having three or more hydroxyl groups and one thiol group in the molecule and a carboxylic acid anhydride (c), that is, a dicarboxylic acid anhydride and a tricarboxylic acid anhydride. In addition, a combination with one or more compounds selected from tetracarboxylic dianhydrides has a solvent-affinity site that has a particularly excellent steric repulsion effect, and an excellent pigment adsorption site that is a large number of continuous pendant carboxyl groups. Have
In particular, the compound (a) having three or more hydroxyl groups and one thiol group in the molecule reacts with a carboxylic acid anhydride (c) containing at least a tetracarboxylic dianhydride to form a polyester chain and continuously. Pendant carboxyl groups can be formed, and this continuous pendant carboxyl group is preferred as an adsorption site for the pigment.

For example, in the presence of the compound (a) having three or more hydroxyl groups and one thiol group in the molecule, radical polymerization of the ethylenically unsaturated monomer (b) results in 3 at one end region. A reaction example in the case where a hydroxyl group in a vinyl polymer (A) having two or more hydroxyl groups is reacted with a tetracarboxylic dianhydride and a dicarboxylic anhydride is shown below.

Reaction process formula (1)


(In the formula, A is a residue excluding a hydroxyl group and a thiol group, which are terminal regions in the vinyl polymer (A), for example, a carbon atom number of 1 to 12 (preferably carbon which may have an oxygen atom). A linear or branched aliphatic or aromatic hydrocarbon group having 1 to 6 atoms, and B is a vinyl polymer portion)

In the dispersant produced by the reaction process formula (1), the core part X ₁ is a reaction residue after the tetracarboxylic dianhydride reacts with a hydroxyl group, and the core part X ₃ is a dicarboxylic acid anhydride. It is a reaction residue after reacting with a hydroxyl group. In this case, a dispersant having a plurality of pendant carboxyl groups present on the polyester chain and further having the vinyl copolymer part B as a solvent affinity site can be obtained.

  In addition, in the presence of the compound (a) having three or more hydroxyl groups and one thiol group in the molecule, the ethylenically unsaturated monomer (b) is obtained by radical polymerization, and 3 in one end region. A reaction example in the case of reacting a hydroxyl group in the vinyl polymer (A) having two or more hydroxyl groups with a tricarboxylic acid anhydride is shown below.

Reaction process formula (2)


(In the formula, A is a residue excluding a hydroxyl group and a thiol group, which are terminal regions in the vinyl polymer (A), for example, a carbon atom number of 1 to 12 (preferably carbon which may have an oxygen atom). A linear or branched aliphatic or aromatic hydrocarbon group having 1 to 6 atoms, and B is a vinyl polymer portion)
In the dispersant produced by the reaction process formula (2), the core part X ₃ is a reaction residue after the tricarboxylic acid anhydride reacts with a hydroxyl group. In this case, a dispersant having a plurality of pendant carboxyl groups in the terminal region of the molecule and further having the vinyl copolymer part B as a solvent affinity site can be obtained.

  In addition, in the presence of the compound (a) having three or more hydroxyl groups and one thiol group in the molecule, the ethylenically unsaturated monomer (b) is obtained by radical polymerization, and 3 in one end region. A reaction example in the case where a hydroxyl group in the vinyl polymer (A) having two or more hydroxyl groups is reacted with a carboxylic acid anhydride is shown below.

Reaction process formula (3)


(In the formula, A is a residue excluding a hydroxyl group and a thiol group, which are terminal regions in the vinyl polymer (A), for example, a carbon atom number of 1 to 12 (preferably carbon which may have an oxygen atom). A linear or branched aliphatic or aromatic hydrocarbon group having 1 to 6 atoms, and B is a vinyl polymer portion)

In the dispersant produced by the reaction process formula (2), the core part X ₃ is a reaction residue after the dicarboxylic acid anhydride has reacted with the hydroxyl group. In this case, a dispersant having a plurality of pendant carboxyl groups in the terminal region of the molecule and further having a vinyl copolymer site B as a solvent affinity site can be obtained.

Examples of the compound (a) having three or more hydroxyl groups and one thiol group in the molecule include 1-mercapto-1,2,2′-ethanetriol, mercaptopentaerythritol; 2- (hydroxymethyl) -2 -(Mercaptomethyl) propane-1,3-diol, 1-mercaptobutane-2,3,4-triol, 2-mercapto-1,3,4-butanetriol, mercaptoditrimethylolethane, mercaptoditrimethylolpropane; 2 -((3-hydroxy-2-mercaptomethyl-2- (methyl) propoxy) methyl) -2- (methyl) propane-1,3-diol, 1-mercaptocyclobutadiene-2,3,4-triol, 4 -Thio-D-galactose, mercaptodipentaerythritol, 4-thio-D-galactose Etc. Moreover, the monoalkyl ester of the said compound can also be used.
Preferably, mercaptopentaerythritol; 2- (hydroxymethyl) -2- (mercaptomethyl) propane-1,3-diol, mercaptoditrimethylolpropane; 2-((3-hydroxy-2-mercaptomethyl-2- (methyl ) Propoxy) methyl) -2- (methyl) propane-1,3-diol, 4-thio-D-galactose.

  A compound (a) having three or more hydroxyl groups and one thiol group in the molecule is adjusted in accordance with the molecular weight of the target vinyl polymer part B, and an ethylenically unsaturated monomer and optionally a polymerization initiator. Can be mixed and heated to obtain a vinyl polymer (A) having three or more hydroxyl groups in one end region. The compound (a) having three or more hydroxyl groups and one thiol group in the molecule is used in an amount of 1 to 30 parts by weight with respect to 100 parts by weight of the ethylenically unsaturated monomer, and bulk polymerization or solution polymerization is performed. It is preferably carried out, more preferably 2 to 12 parts by weight, still more preferably 2 to 10 parts by weight. The reaction temperature is 40 to 150 ° C, preferably 50 to 110 ° C.

By using a compound (a) in the said preferable range, the molecular weight of the vinyl polymer part B can be adjusted to a suitable range. The gel polymer permeation chromatography (GPC) measurement polystyrene conversion weight average molecular weight of the vinyl polymer part B is preferably 1000 to 10,000, more preferably 2000 to 8000, and still more preferably 2000 to 6000. Since this part B becomes an affinity part for the solvent as a dispersion medium, if the weight average molecular weight of the vinyl polymer part B is less than 1000, the effect of steric repulsion by the solvent affinity part is reduced and aggregation of the pigment is prevented. The dispersion stability may be insufficient. On the other hand, if it exceeds 10,000, the absolute amount of the solvent affinity part may increase, and the dispersibility effect itself may decrease. Further, the viscosity of the dispersion may increase. The vinyl polymer portion B can be easily adjusted in molecular weight within the above range, and has good affinity for the solvent.

  In the polymerization, 0.001 to 5 parts by weight of a polymerization initiator can be arbitrarily used with respect to 100 parts by weight of the ethylenically unsaturated monomer. As the polymerization initiator, an azo compound and an organic peroxide can be used. Examples of the azo compounds include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane 1-carbonitrile), 2 , 2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2′-azobis (2-methylpropionate) 4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2-hydroxymethylpropionitrile), 2,2′-azobis [2- (2-imidazolin-2-yl) Propane] and the like. Examples of organic peroxides include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di (2-ethoxyethyl) peroxy Examples thereof include dicarbonate, t-butyl peroxyneodecanoate, t-butyl peroxybivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, and diacetyl peroxide. These polymerization initiators can be used alone or in combination of two or more.

  In the case of solution polymerization, ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, xylene, acetone, hexane, methyl ethyl ketone, cyclohexanone and the like are used as the polymerization solvent, but are not particularly limited thereto. These polymerization solvents may be used as a mixture of two or more.

  Examples of the ethylenically unsaturated monomer (b) include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl. (Meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl ( (Meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, oxetane (meth) acrylate, etc. Alkoxypolyalkylene glycol (meth) acrylates such as toxipolypropylene glycol (meth) acrylate and ethoxypolyethylene glycol (meth) acrylate, (meth) acrylamide, and N, N-dimethyl (meth) acrylamide, N, N-diethyl (meta) ) N-substituted (meth) acrylamides such as acrylamide, N-isopropyl (meth) acrylamide, diacetone (meth) acrylamide, acryloylmorpholine, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl ( Examples include amino group-containing (meth) acrylates such as (meth) acrylate and nitriles such as (meth) acrylonitrile.

Examples of monomers that can be used in combination with the acrylic monomer include styrenes such as styrene and α-methylstyrene, vinyl ethers such as ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, and isobutyl vinyl ether, and acetic acid. And fatty acid vinyls such as vinyl and vinyl propionate.
Moreover, a carboxyl group-containing ethylenically unsaturated monomer can be used in combination. As the carboxyl group-containing ethylenically unsaturated monomer, one or more kinds can be selected from acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid and the like.

  In the present invention, among the ethylenically unsaturated monomers (b) exemplified above, it is preferable from the viewpoint of dispersibility to use a monomer represented by the following general formula (4).

General formula (4)


[In General Formula (4), R ² is a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic alkyl group having 6 to 15 carbon atoms. ]

  Next, the process of reacting the carboxylic acid anhydride with the vinyl polymer (A) having two or more hydroxyl groups at one end will be described.

Examples of the carboxylic acid anhydride used in the present invention include dicarboxylic acid anhydride, tricarboxylic acid anhydride, and tetracarboxylic dianhydride. These can be used alone or in combination according to the structure of the intended pigment dispersant.
Examples of dicarboxylic acid anhydrides include succinic acid anhydride, maleic acid anhydride, phthalic acid anhydride, itaconic acid anhydride, glutaric acid anhydride, dodecenyl succinic acid anhydride, and chlorendic acid anhydride. .

  Examples of the tricarboxylic acid anhydride include aliphatic tricarboxylic acid anhydrides and aromatic tricarboxylic acid anhydrides.

  Examples of the aliphatic tricarboxylic acid anhydride include 3-carboxymethylglutaric acid anhydride, 1,2,4-butanetricarboxylic acid-1,2-anhydride, cis-propene-1,2,3-tricarboxylic acid- 1,2-anhydride, 1,3,4-cyclopentanetricarboxylic acid anhydride, etc. are mentioned.

  Examples of the aromatic tricarboxylic acid include benzenetricarboxylic acid anhydride (1,2,3-benzenetricarboxylic acid anhydride, trimellitic acid anhydride [1,2,4-benzenetricarboxylic acid anhydride], etc.), naphthalenetricarboxylic acid, and the like. Acid anhydride (1,2,4-naphthalenetricarboxylic acid anhydride, 1,4,5-naphthalenetricarboxylic acid anhydride, 2,3,6-naphthalenetricarboxylic acid anhydride, 1,2,8-naphthalenetricarboxylic acid anhydride Products), 3,4,4′-benzophenone tricarboxylic acid anhydride, 3,4,4′-biphenyl ether tricarboxylic acid anhydride, 3,4,4′-biphenyl tricarboxylic acid anhydride, 2,3,2 ′ -Biphenyltricarboxylic acid anhydride, 3,4,4'-biphenylmethanetricarboxylic acid anhydride, 3,4,4'-biphenyl Sulfonic tricarboxylic acid anhydrides. When tricarboxylic acid anhydride is used, aromatic tricarboxylic acid anhydride is particularly preferable among the above, and trimellitic acid anhydride is more preferable.

Examples of tetracarboxylic dianhydrides include 1,2,3,4-butanetetracarboxylic anhydride, 1,2,3,4-cyclobutanetetracarboxylic anhydride, 1,3-dimethyl-1,2,3. , 4-cyclobutanetetracarboxylic anhydride, 1,2,3,4-cyclopentanetetracarboxylic anhydride, 2,3,5-tricarboxycyclopentylacetic anhydride, 3,5,6-tricarboxynorbornane-2 -Acetic anhydride, 2,3,4,5-tetrahydrofurantetracarboxylic anhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, Aliphatic tetracarboxylic anhydrides such as bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetracarboxylic anhydride;
Pyromellitic anhydride, ethylene glycol ditrimellitic anhydride, propylene glycol ditrimellitic anhydride, butylene glycol ditrimellitic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride, 3,3 ′, 4,4′-biphenylsulfonetetracarboxylic anhydride, 1,4,5,8-naphthalenetetracarboxylic anhydride, 2,3,6,7-naphthalenetetracarboxylic anhydride, 3, 3 ', 4,4'-biphenyl ether tetracarboxylic acid anhydride, 3,3', 4,4'-dimethyldiphenylsilane tetracarboxylic acid anhydride, 3,3 ', 4,4'-tetraphenylsilane tetracarboxylic acid Acid anhydride, 1,2,3,4-furantetracarboxylic acid anhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diph Nyl sulfide anhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylsulfone anhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylpropane anhydride, 3,3 ′, 4,4′-perfluoroisopropylidenediphthalic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic anhydride, bis (phthalic acid) phenylphosphine oxide anhydride, p-phenylene-bis (tri Phenylphthalic acid anhydride, m-phenylene-bis (triphenylphthalic acid) anhydride, bis (triphenylphthalic acid) -4,4′-diphenyl ether anhydride, bis (triphenylphthalic acid) -4,4 ′ -Diphenylmethane anhydride, 9,9-bis (3,4-dicarboxyphenyl) fluoric anhydride, 9,9-bis [4- (3,4-dicarboxyl) Ciphenoxy) phenyl] fluorenic anhydride, 3,4-dicarboxy-1,2,3
Aromatic tetracarboxylic anhydrides such as 4-tetrahydro-1-naphthalene succinic anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-6-methyl-1-naphthalene succinic anhydride Is mentioned.

  The tetracarboxylic dianhydride used in the present invention is not limited to the compounds exemplified above, and may have any structure as long as it has two carboxylic anhydride groups. These may be used alone or in combination. What is preferably used in the present invention is an aromatic tetracarboxylic dianhydride from the viewpoint of reducing the viscosity of the pigment dispersion or various inks. Furthermore, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, ethylene glycol ditrimellitic anhydride ester, 3,3 ′, 4,4′-benzophenobiphenyl Ether tetracarboxylic dianhydride, 9,9-bis (3,4-dicarboxyphenyl) fluorene dianhydride, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, 2,3 , 6,7-Naphthalenetetracarboxylic dianhydride and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride are preferred.

  As the catalyst used for reacting the acid anhydride group and the hydroxyl group of the present invention, a known catalyst can be used. The catalyst is preferably a tertiary amine compound such as triethylamine, triethylenediamine, N, N-dimethylbenzylamine, N-methylmorpholine, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1, 5-diazabicyclo- [4.3.0] -5-nonene and the like.

  The pigment dispersant of the present invention can be obtained by reacting a vinyl polymer (A) having three or more hydroxyl groups in one terminal region with a carboxylic acid anhydride (c). The molar ratio [A] of the hydroxyl group in the vinyl polymer (A) having three or more hydroxyl groups in one terminal region and the molar ratio [c] of the anhydride group in the carboxylic acid anhydride (c) are 0. 3 <[c] / [A] ≦ 1.0 is preferable, more preferably 0.5 <[c] / [A] ≦ 1.0, and most preferably 0.6 <[c] / [A ] ≦ 1.0. If it is 0.3 or less, the acid anhydride residue as the pigment adsorbing part may be decreased, and the acid value of the resin may be decreased. If it is greater than 1.0, the unreacted acid anhydride group May remain, resulting in poor storage stability.

  The reaction temperature is 80 ° C to 180 ° C, preferably 90 ° C to 160 ° C. When the reaction temperature is less than 80 ° C., the reaction rate is slow. When the reaction temperature exceeds 180 ° C. or more, the carboxyl group undergoes an esterification reaction, which may cause a decrease in acid value or gelation. Ideally, the reaction is stopped until the absorption of the acid anhydride is eliminated by infrared absorption, but the reaction is conducted after confirming that 95% or more of the acid anhydride is half-esterified by acid value measurement. May be stopped.

  The weight average molecular weight measured by gel permeation chromatography (GPC) of the obtained pigment dispersant is preferably 2000 to 35000, more preferably 4000 to 25000, still more preferably 6000 to 20000, and particularly preferably 7000 to 15000. is there. If the weight average molecular weight is less than 2,000, the stability of the pigment composition may be lowered, and if it exceeds 35,000, the interaction between the resins becomes strong and the viscosity of the pigment composition may increase. The acid value of the obtained pigment dispersant is preferably 5 to 200. More preferably, it is 10-150, More preferably, it is 15-100, Most preferably, it is 20-80. If the acid value is less than 5, the pigment adsorbing ability may be reduced and the pigment dispersibility may be problematic, and if it exceeds 200, the interaction between the resins may become strong and the viscosity of the pigment dispersion composition may be increased.

Furthermore, in the present invention, the step of reacting the compound (a) having three or more hydroxyl groups and one thiol group in the molecule with the carboxylic acid anhydride (c) to produce a compound having a carboxyl group and a thiol group. And in the presence of the compound obtained by the above step, the ethylenically unsaturated monomer (b) can be radically polymerized using the remaining thiol group as a chain transfer agent to obtain a resin having a similar structure. it can.
The molar ratio [a] of the hydroxyl group in the compound (a) having three or more hydroxyl groups and one thiol group in the molecule and the molar ratio [c] of the anhydride group in the carboxylic acid anhydride (c) are: 0.3 <[c] / [a] ≦ 1.0, more preferably 0.5 <[c] / [a] ≦ 1.0, and most preferably 0.6 <[c]. /[A]≦1.0. If it is 0.3 or less, the acid anhydride residue as the pigment adsorbing part may be decreased, and the acid value of the resin may be decreased. If it is greater than 1.0, the unreacted acid anhydride group May remain, resulting in poor storage stability.

  Next, a compound having a carboxyl group and a thiol group obtained by reacting a compound (a) having three or more hydroxyl groups and one thiol group in the molecule with a carboxylic acid anhydride (c) In accordance with the molecular weight of the vinyl polymer part B, the pigment dispersant introduced with the vinyl polymer part B by mixing and heating the ethylenically unsaturated monomer (b) and optionally a polymerization initiator Can be manufactured. Preferably, a compound obtained by reacting a compound (a) having three or more hydroxyl groups and one thiol group in the molecule with a carboxylic acid anhydride (c) is used as the ethylenically unsaturated monomer (b) 100. Bulk polymerization or solution polymerization is performed using 0.5 to 40 parts by weight with respect to parts by weight. The reaction temperature is 40 to 150 ° C., preferably 50 to 110 ° C., and the reaction time is 3 to 30 hours, preferably 5 to 20 hours.

  As the ethylenically unsaturated monomer (b) to be used, since the acid anhydride group has already been reacted in the previous step, not only the unsaturated monomer shown above but also the reactivity with the acid anhydride group What has the site | part which carries out can also be used. For example, an ethylenically unsaturated monomer having a hydroxyl group can be mentioned.

  The ethylenically unsaturated monomer having a hydroxyl group may be any monomer as long as it has a hydroxyl group and has an ethylenically unsaturated double bond. Specifically, it has a hydroxyl group. (Meth) acrylate monomers such as 2-hydroxyethyl (meth) acrylate, 2 (or 3) -hydroxypropyl (meth) acrylate, 2 (or 3 or 4) -hydroxybutyl (meth) acrylate and cyclohexanedi Hydroxyalkyl (meth) acrylates such as methanol mono (meth) acrylate, alkyl-α-hydroxyalkyl acrylates such as ethyl-α-hydroxymethyl acrylate, or (meth) acrylamide monomers having a hydroxyl group, such as N- (2-hydroxyethyl) (meth) acrylamide, N- (2 N- (hydroxyalkyl) (meth) acrylamide such as hydroxypropyl) (meth) acrylamide, N- (2-hydroxybutyl) (meth) acrylamide, or vinyl ether monomers having a hydroxyl group, such as 2-hydroxyethyl Hydroxyalkyl vinyl ethers such as vinyl ether, 2- (or 3-) hydroxypropyl vinyl ether, 2- (or 3- or 4-) hydroxybutyl vinyl ether, or allyl ether monomers having a hydroxyl group, such as 2-hydroxyethyl allyl Examples thereof include hydroxyalkyl allyl ethers such as ether, 2- (or 3-) hydroxypropyl allyl ether, and 2- (or 3- or 4-) hydroxybutyl allyl ether.

  Also obtained by adding alkylene oxide and / or lactone to the above hydroxyalkyl (meth) acrylate, alkyl-α-hydroxyalkyl acrylate, N- (hydroxyalkyl) (meth) acrylamide, hydroxyalkyl vinyl ether or hydroxyalkylallyl ether. The ethylenically unsaturated monomer obtained can also be used as an ethylenically unsaturated monomer having a hydroxyl group in the method of the present invention. As the alkylene oxide to be added, ethylene oxide, propylene oxide, 1,2-, 1,4-, 2,3- or 1,3-butylene oxide and a combination system of two or more thereof are used. When two or more kinds of alkylene oxide are used in combination, the bonding form may be random and / or block. As the lactone to be added, δ-valerolactone, ε-caprolactone, ε-caprolactone substituted with an alkyl group having 1 to 6 carbon atoms, and a combination system of two or more of these are used. What added both alkylene oxide and lactone may be used.

  The dispersant of the present invention can be produced using only the raw materials mentioned so far, but it is preferable to use a solvent in order to avoid problems such as high viscosity and non-uniform reaction. As the solvent to be used, known solvents can be used. For example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, butyl acetate, toluene, xylene, acetonitrile, PGMAC (methoxypropyl acetate) and the like can be mentioned. The solvent used for the reaction can be removed by an operation such as distillation after the completion of the reaction, or can be used as a part of the product as it is.

  Examples of the pigment that can be dispersed with the dispersant of the present invention include various pigments used in inks and the like. Such organic pigments include soluble azo pigments, insoluble azo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, perylene pigments, perinone pigments, dioxazine pigments, anthraquinone pigments, dianthraquinonyl pigments, anthrapyrimidines Pigment, Ansanthrone pigment, Indanthrone pigment, Flavanthrone pigment, Pyranthrone pigment, Diketopyrrolopyrrole pigment, etc. More specific examples are shown by generic names of Color Index: Pigment Black 7, Pigment Blue 6, 15, 15: 1, 15: 6, 15: 4, 15: 6, 60, pigment green 7, 36, 57, pigment red 9, 48, 49, 52, 53, 57, 97, 122, 144, 146 149, 166, 168, 177, 78,179,185,206,207,209,220,221,238,242,254,255, pigment violet 19,23,29,30,37,40,50, pigment yellow 12,13,14,17, 20, 24, 74, 83, 86, 93, 94, 95, 109, 110, 117, 120, 125, 128, 137, 138, 139, 147, 148, 150, 151, 154, 155, 166, 168, 180, 185, pigment orange 13, 36, 37, 38, 43, 51, 55, 59, 61, 64, 71, 74, and the like. However, it is not limited to illustration.

Examples of inorganic pigments include inorganic oxides, inorganic hydroxides, inorganic salts, and metal powders.
Examples of inorganic oxides include metal, non-metal, and sub-metal oxides. Specific examples include aluminum oxide, zinc oxide, antimony oxide, indium oxide, calcium oxide, cadmium oxide, silver oxide, gold oxide, Chromium oxide, silicon oxide, cobalt oxide, zirconium oxide, tin oxide, titanium oxide, iron oxide, copper oxide, nickel oxide, platinum oxide, palladium oxide, bismuth oxide, magnesium oxide, manganese oxide, molybdenum oxide, vanadium oxide, oxidation Barium etc. are mentioned. Furthermore, antimony-containing tin oxide (ATO), tin-containing indium oxide (ITO), phosphorus-containing tin oxide (PTO), fluorine, which are inorganic oxides whose conductivity is improved by dissolving a dopant in the inorganic oxide. Examples thereof include tin oxide (FTO), aluminum-containing zinc oxide (AZO), and gallium-containing zinc oxide (GZO).
Examples of the inorganic hydroxide include alumina white and viridian.
Examples of the inorganic salt include barium sulfate, calcium carbonate, white carbon, and clay.
Examples of the metal powder include aluminum powder, zinc powder, or bronze powder.
Among these, an inorganic oxide is preferable from the viewpoint of dispersibility.

The pigment composition using the dispersant of the present invention further includes a pigment derivative having a basic group, an anthraquinone derivative having a basic group, an acridone derivative having a basic group, and a triazine derivative having a basic group. It is preferable to contain at least one basic derivative selected from: Here, the pigment derivative is obtained by introducing a specific substituent into the organic pigment residue described in the color index. In the present invention, a pigment derivative having a basic group is used. By including a basic derivative, a pigment that is difficult to disperse without a basic derivative (particularly, in the case of an organic pigment) is preferable because a pigment composition excellent in dispersibility, fluidity, and storage stability can be obtained.
The basic derivative is a compound represented by the following general formula (5), and is a derivative having a specific parent skeleton having a basic group. There is no particular limitation as long as it is a pigment derivative having a basic group.

  General formula (5):

P-Lm
[In General Formula (5), P is an m-valent organic pigment residue, an anthraquinone skeleton, an acridone skeleton, or a triazine skeleton, m is an integer of 1 to 4, and L is a general formula ( 6) A substituent selected from the group represented by (7) or (8). ]

  General formula (6):

  General formula (7):

  General formula (8):

[In the general formulas (6) to (8),
X _{is, -SO 2 -, - CO -} , - CH 2 -, - CH 2 NHCOCH 2 -, - CH 2 NHSO 2 CH 2 -, or a direct bond,
Y ⁰ is —NH—, —O—, or a direct bond;
n is an integer of 1 to 10,
Y ¹ is —NH—, —NR ¹⁹ —Z—NR ²⁰ —, or a direct bond;
R ¹⁹ and R ²⁰ are each independently a hydrogen bond, an optionally substituted alkyl group having 1 to 36 carbon atoms, an optionally substituted alkenyl group having 2 to 36 carbon atoms, or A phenyl group which may have a substituent,
Z is an alkylene group which may have a substituent, or an arylene group which may have a substituent,
R ¹¹ and R ¹² are each independently a hydrogen atom, an optionally substituted alkyl group having 1 to 30 carbon atoms, an optionally substituted alkenyl group having 2 to 30 carbon atoms, or R ¹¹ and R ¹² together are a heterocyclic ring which may have a substituent, further containing a nitrogen, oxygen or sulfur atom,
R ¹³ , R ¹⁴ , R ¹⁵ , and R ¹⁶ are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms that may have a substituent, or 2 to carbon atoms that may have a substituent. 20 alkenyl group, an arylene group having 6 to 20 carbon atoms which may have a substituent,
R ¹⁷ is a hydrogen atom, an optionally substituted alkyl group having 1 to 20 carbon atoms, an optionally substituted alkenyl group having 2 to 20 carbon atoms,
R ¹⁸ is a substituent represented by the general formula (6) or a substituent represented by the general formula (7), and Q is a hydroxyl group, an alkoxyl group, or a substituent represented by the general formula (6). Or a substituent represented by the general formula (7). ]

Examples of the amine component used to form the substituents represented by the general formulas (6) to (8) include dimethylamine, diethylamine, methylethylamine, N, N-ethylisopropylamine, N, N-ethyl. Propylamine, N, N-methylbutylamine, N, N-methylisobutylamine, N, N-butylethylamine, N, N-tert-butylethylamine, diisopropylamine, dipropylamine, N, N-sec-butylpropylamine , Dibutylamine, di-sec-butylamine, diisobutylamine, N, N-isobutyl-sec-butylamine, diamylamine, diisoamylamine, dihexylamine, dicyclohexylamine, di (2-ethylhexyl) amine, dioctylamine, N, N-methyloctadeci Amine, didecylamine, diallylamine, N, N-ethyl-1,2-dimethylpropylamine, N, N-methylhexylamine, dioleylamine, distearylamine, N, N-dimethylaminomethylamine, N, N-dimethylamino Ethylamine, N, N-dimethylaminoamylamine, N, N-dimethylaminobutylamine, N, N-diethylaminoethylamine, N, N-diethylaminopropylamine, N, N-diethylaminohexylamine, N, N-diethylaminobutylamine, N , N-diethylaminopentylamine, N, N-dipropylaminobutylamine, N, N-dibutylaminopropylamine, N, N-dibutylaminoethylamine, N, N-dibutylaminobutylamine, N, N-diisobutylaminopen Ruamine, N, N-methyl-laurylaminopropylamine, N, N-ethylhexylaminoethylamine, N, N-distearylaminoethylamine, N, N-dioleylaminoethylamine, N, N-distearylaminobutylamine, Piperidine, 2-Pipecoline, 3-Pipecoline, 4-Pipecoline, 2,4-Lupetidine, 2,6-Lupetidine, 3,5-Lupetidine, 3-
Piperidine methanol, pipecolic acid, isonipecotic acid, methyl isonipecotate, ethyl isonipecotate, 2-piperidine ethanol, pyrrolidine, 3-hydroxypyrrolidine, N-aminoethylpiperidine, N-aminoethyl-4-pipecholine, N-aminoethylmorpholine, N-aminopropylpiperidine, N-aminopropyl-2-pipecoline, N-aminopropyl-4-pipecoline, N-aminopropylmorpholine, N-methylpiperazine, N-butylpiperazine, N-methylhomopiperazine, 1-cyclopentylpiperazine 1-amino-4-methylpiperazine, 1-cyclopentylpiperazine, and the like.

  The pigment derivative, anthraquinone derivative, and acridone derivative having a basic substituent of the present invention can be synthesized by various synthetic routes. For example, after introducing the substituents represented by the following general formulas (9) to (12) into an organic dye, anthraquinone, or acridone, the substituents represented by the general formulas (6) to (8) react with the above substituents. The amine component forming the group, for example, N, N-dimethylaminopropylamine, N-methylpiperazine, diethylamine, or 4- [4-hydroxy-6- [3- (dibutylamino) propylamino] -1,3 , 5-triazin-2-ylamino] aniline and the like.

Formula (9): —SO ₂ Cl
Formula (10): -COCl
Formula _{(11): -CH 2 NHCOCH 2} Cl
Formula (12): —CH ₂ Cl

  In the reaction of the substituents of the general formulas (9) to (12) with the amine component, a part of the substituents of the general formulas (9) to (12) are hydrolyzed and chlorine is substituted with a hydroxyl group. It may be mixed. In that case, the general formula (9) and the general formula (10) are respectively a sulfonic acid group and a carboxylic acid group. Or a salt with a monoamine.

  When the organic dye is an azo dye, the substituent represented by the general formulas (6) to (8) is previously introduced into the diazo component or the coupling component, and then the coupling reaction is performed, thereby performing the azo pigment. Derivatives can also be produced.

  The triazine derivative having a basic group of the present invention can be synthesized by various synthetic routes. For example, starting from cyanuric chloride, an amine component that forms a substituent represented by general formulas (6) to (8) on at least one chlorine of cyanuric chloride, such as N, N-dimethylaminopropylamine or N- It can be obtained by reacting methylpiperazine or the like and then reacting the remaining chlorine of cyanuric chloride with various amines or alcohols.

  In the pigment composition of the present invention, the amount of the pigment derivative having a base substituent is preferably 1 to 50 parts by weight, more preferably 3 to 30 parts by weight, most preferably 5 to 25 parts per 100 parts by weight of the pigment. Parts by weight. When the basic derivative is less than 1 part by weight relative to 100 parts by weight of the pigment, the dispersibility may be deteriorated, and when it exceeds 50 parts by weight, the heat resistance and light resistance may be deteriorated.

  The pigment composition using the dispersant of the present invention is mixed with various solvents, resins, additives, etc. as necessary, and dispersed by a horizontal sand mill, vertical sand mill, annular bead mill, attritor, etc. A pigment dispersion obtained by dispersing the product in a varnish can be prepared. Pigments, basic derivatives, dispersants, other resins and additives may be dispersed after mixing all the components, but only the pigments and basic derivatives or the basic derivatives and dispersants may be mixed first. Or only the pigment, the basic derivative, and the dispersant may be dispersed, and then another component may be added and dispersed again.

Also, before dispersing with a horizontal sand mill, vertical sand mill, annular bead mill, attritor, etc., pre-dispersion using a kneader mixer such as a kneader, 3-roll mill, solid dispersion with 2-roll mill, etc., or pigment Treatment with a basic derivative and / or a dispersant may be performed. In addition, any disperser or mixer such as a high speed mixer, a homomixer, a ball mill, a roll mill, a stone mill, or an ultrasonic disperser can be used for producing the pigment dispersion. Examples of various solvents that can be used in the pigment dispersion include organic solvents and water. Moreover, when using for an active energy ray hardening-type composition, you may use an active energy ray-curable liquid monomer and liquid oligomer as a medium instead of a solvent.

  The pigment composition of the present invention can be used as various printing inks and ink-jet inks, and can be used as a pigment dispersion by adding a varnish in order to impart fixability during color development. Resins that can be used as varnish include petroleum resin, casein, shellac, rosin modified maleic resin, rosin modified phenolic resin, nitrocellulose, cellulose acetate butyrate, cyclized rubber, chlorinated rubber, oxidized rubber, hydrochloric acid rubber, phenolic resin, Alkyd resin, polyester resin, unsaturated polyester resin, amino resin, epoxy resin, vinyl resin, vinyl chloride, vinyl chloride-vinyl acetate acidic group-containing urethane resin, acrylic resin, methacrylic resin, polyurethane resin, silicone resin, fluororesin, dryness Examples thereof include oil, synthetic drying oil, styrene-modified maleic acid, polyamide resin, chlorinated polypropylene, butyral resin, and vinylidene chloride resin.

  The pigment dispersion of the present invention can be used for non-aqueous, aqueous or solvent-free paints, gravure ink, offset ink, ink jet ink, color filter ink, digital paper ink, plastic coloring, and the like.

Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. In the examples and comparative examples, “part” means “part by weight”.
Example 1
In a reaction vessel equipped with a gas introduction tube, a thermometer, a condenser, and a stirrer, 200 parts of n-butyl acrylate and 800 parts of methyl methacrylate were charged and replaced with nitrogen gas. The inside of the reaction vessel was heated to 80 ° C., 52 parts of 4-thio-D-galactose was added, and reacted for 12 hours. It was confirmed that 95% had reacted by the solid content measurement (first step). Next, 500 parts of a 50% solid methoxypropyl acetate solution of the compound obtained in the first step, 11.0 parts of pyromellitic acid anhydride, and 1,8-diazabicyclo- [5.4.0] as a catalyst. 1.04 part of -7-undecene was charged and reacted at 120 ° C. for 7 minutes. It was made to react until the acid anhydride of 98% or more was half-esterified by the measurement of an acid value (2nd process). The reaction solution was cooled and the solid content was adjusted with methoxypropyl acetate to obtain a 50% solid solution of Dispersant 1. The obtained dispersant had an acid value of 25 and a weight average molecular weight of 160000.
(Examples 2 to 5)
The synthesis was carried out in the same manner as in Example 1 except that the raw materials and preparation amounts shown in Table 1 were used, and a 50% solid solution of dispersants 2 to 5 was obtained.

(Example 6)
In a reaction vessel equipped with a gas introduction tube, a thermometer, a condenser and a stirrer, 187 parts of mercaptopentaerythritol (2- (hydroxymethyl) -2- (mercaptomethyl) propane-1,3-diol), BPDA (3, 3 ', 4,4'-biphenyltricarboxylic anhydride) 217 parts, 931 parts of PGMAc (methoxypropyl acetate), and 0.2 parts of monobutyltin oxide as a catalyst were substituted with nitrogen gas and reacted at 120 ° C for 5 hours. (First step). It was confirmed by acid value measurement that 95% or more of the acid anhydride was half-esterified. Next, 410 parts of the compound obtained in the first step with a 30% solution of methoxypropyl acetate, 200 parts of 2-hydroxypropyl methacrylate, 200 parts of t-butyl acrylate, 200 parts of 2-methoxyethyl acrylate, 400 parts of methyl methacrylate , 87 parts of PGMAc were charged, the inside of the reaction vessel was heated to 80 ° C., 1.2 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) was added, and the reaction was performed for 12 hours (second step). It was confirmed that 95% had reacted by solid content measurement. The reaction solution was cooled and the solid content was adjusted with methoxypropyl acetate to obtain a 50% solid solution of Dispersant 6. The obtained dispersant had an acid value of 25 and a weight average molecular weight of 12,000.
(Examples 7 to 10)
The synthesis was carried out in the same manner as in Example 6 except that the raw materials and preparation amounts shown in Table 2 were used, and a 50% solid solution of dispersants 7 to 10 was obtained.

PMA: pyromellitic dianhydride BTA: 1,2,3,4-butanetetracarboxylic dianhydride BPDA: 3,3 ', 4,4'-biphenyltricarboxylic acid anhydride TMEG: ethylene glycol ditrimethyl anhydride Acid ester BTDA: 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride DSDA: 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride BPAF: 9,9-bis (3 , 4-dicarboxyphenyl) fluorene dianhydride TMA: trimellitic anhydride HEMA: 2-hydroxyethyl methacrylate 2HPMA: 2-hydroxypropyl methacrylate EA: ethyl acrylate BA: butyl acrylate tBA: t-butyl acrylate 2MTA: 2 -Methoxyethyl acrylate MMA: methyl Methacrylate BMA: n-butyl methacrylate BzMA: benzyl methacrylate St: styrene MAA: methacrylic acid

(Comparative Examples 1-4)
(Comparative Example 1)
In a four-necked flask equipped with a stirrer, reflux condenser, gas inlet tube, thermometer, and dropping funnel, 559 parts of dimethyl terephthalate, 420 parts of propylene glycol, 21.2 parts of glycerin, 0.2 part of zinc acetate, tetrabutyl ortho 0.025 parts of titanate was charged, and a transesterification reaction was performed at 160 to 220 ° C. with stirring under a nitrogen stream. When 95% (175 g) or more of the theoretical amount of methanol was distilled, the inside of the flask was gradually depressurized and reacted at 1 to 3 torr and 240 ° C. for 3 hours to obtain a polyester having a hydroxyl group at the terminal. Next, the flask was depressurized with nitrogen and gradually cooled to 200 ° C. When the temperature reached 200 ° C., 65 parts of succinic anhydride was added and reacted for 1 hour to obtain Comparative Dispersant 1 having an acid value of 40 and a weight average molecular weight of 12,000. (Comparative Example 2)
A 4-flask equipped with a stirrer, reflux condenser, gas inlet tube, thermometer, and dropping funnel was charged with 75 parts of cyclohexanone, 17.8 parts of neopentyl glycol, 31.9 parts of pyromellitic anhydride, and 150 to 160 ° C. The reaction was carried out for 5 hours in a nitrogen gas atmosphere. When the resin acid value became 334 or less, the mixture was cooled, 249.7 parts of ε-caprolactone and 0.6 parts of tetrabutyl titanate were added, and the mixture was stirred at 150 ° C. for 5 hours. When the heating residue reached 76% or more, the mixture was cooled and 625 parts of cyclohexanone was added to obtain Comparative Dispersant 2 having an acid value of 54 and a weight average molecular weight of 12900. The comparative dispersant 2 prepared in Comparative Example 2 corresponds to the dispersant described in Patent Document 2.

(Comparative Example 3)
In a four-necked flask equipped with a stirrer, reflux condenser, gas inlet tube, thermometer, and dropping funnel, 19.8 parts of xylene, 2.1 parts of octanol, 77.9 parts of ε-caprolactone, 0.16 parts of tetrabutyl titanate Was heated to 150 to 160 ° C. and reacted for 5 hours in a nitrogen gas atmosphere. After confirming that the heating residue was 78% or more, the mixture was cooled to obtain a polyester monool. 31.86 parts of the synthesized polyester monool and 0.98 parts of trimellitic anhydride were charged and reacted at 150 to 160 ° C. in a nitrogen atmosphere. When the resin acid value became 22.7 or less, YED122 (trade name alkylphenol monoglycidyl ether, epoxy equivalent 250, manufactured by Japan Epoxy Resin Co., Ltd.) and 2.55 parts were charged and reacted at the same temperature. When the resin acid value became 1.1 or less, 1.96 parts of trimellitic anhydride was added and reacted at the same temperature, and when the resin acid value became 38.7 or less, YED122, 5.1 parts And the reaction is carried out at the same temperature. When the resin acid value becomes 1.8 or less, 3.92 parts of trimellitic anhydride is added and the reaction is carried out at the same temperature, and the resin acid value is reduced to 60.1 or less. At that time, the reaction mixture was cooled and 53.6 parts of xylene was added to terminate the reaction. Comparative dispersant 3 having an acid value of 58.9 and a weight average molecular weight of 11,000 was obtained. The comparative dispersant 3 prepared in this Comparative Example 3 corresponds to the dispersant described in Patent Document 3.
(Comparative Example 4)
In a reaction vessel equipped with a gas introduction tube, a thermometer, a condenser, and a stirrer, 200 parts of n-butyl methacrylate was charged and replaced with nitrogen gas. The inside of the reaction vessel was heated to 80 ° C., and 12 parts of 3-mercapto-1,2-propanediol was added and reacted for 12 hours. It was confirmed that 95% had reacted by solid content measurement. Next, 12 parts of pyromellitic anhydride, 224 parts of cyclohexanone, and 0.40 part of 1,8-diazabicyclo- [5.4.0] -7-undecene as a catalyst were added and reacted at 120 ° C. for 7 hours. . By measuring the acid value, it was confirmed that 98% or more of the acid anhydride was half-esterified, and the reaction was terminated to obtain a comparative dispersant 4 having an acid value of 28 and a weight average molecular weight of 5800. The comparative dispersant 4 prepared in Comparative Example 4 corresponds to the dispersant described in Patent Document 5.

At least one basic substituent selected from the group consisting of a dye derivative having a basic substituent, an anthraquinone derivative having a basic substituent, an acridone derivative having a basic substituent, and a triazine derivative having a basic substituent The dispersant having the above is abbreviated as a dispersant having a basic substituent.

[Production Example 1 of Dispersant Having Basic Substituent]
After chlorosulfonating 50 parts of copper phthalocyanine as a dye component, it is reacted with 14 parts of N, N-dimethylaminopropylamine as an amine component to give a dye derivative 1 having a basic group represented by the following general formula (25) 62 parts were obtained.

Pigment derivative 1 having a basic substituent
Formula (25):

CuPc represents a copper phthalocyanine residue.

[Production Example 2 of dispersant having basic substituent]
Chloromethylation of 50 parts of copper phthalocyanine, which is a pigment component, was followed by reaction with 40 parts of dibutylamine, which was an amine component, to obtain 95 parts of pigment derivative 2 having a basic substituent represented by the following general formula (26). .

Pigment derivative 2 having a basic substituent
General formula (26):

CuPc represents a copper phthalocyanine residue.

[Production Example 3 of dispersing agent having basic substituent]
Chloroacetamidomethylation of 50 parts of quinacridone, which is a dye component, is then reacted with 40 parts of N-methylpiperazine, which is an amine component, to obtain 103 parts of dye derivative 3 having a basic substituent represented by the following general formula (27). Obtained.

Pigment derivative 3 having a basic substituent
Formula (27):

[Production Example 4 of dispersant having basic substituent]
By using diphenyl diketopyrrolopyrrole as a dye component and N-aminopropylmorpholine as an amine component, a dye derivative 4 having a basic substituent represented by the following general formula (28) is obtained by the same method as in Production Example 1. It was.

Dye derivative 4 having a basic substituent
Formula (28):

[Production Examples 5 to 10 of dispersant having basic substituent]
A pigment derivative, anthraquinone derivative, acridone derivative, and triazine derivative having the following basic substituents were obtained by the same method as in Production Examples 1 to 4 of the pigment derivative having the basic group.

Anthraquinone derivative having basic substituent (Dye derivative 5 having basic substituent)
Formula (29):

Pigment derivative having basic substituent 6
Formula (30):

Pigment derivative having basic substituent 7
Formula (31):

Pigment derivative having basic substituent 8
Formula (32):

Acridone derivatives having basic substituents (pigment derivative 9 having basic substituents)
Formula (33):

Triazine derivative having basic substituent (pigment derivative 10 having basic substituent)
Formula (34):

  In the same manner as in Production Examples 1 to 10 of the dispersant having a basic substituent as described above, the pigment component, anthraquinone, acridone or triazine is reacted with the amine component, or the compound having the amine component is cupped. By synthesizing a dye by ring reaction, as a dispersant having various basic groups constituting the present invention, a dye derivative having a basic substituent, an anthraquinone derivative having a basic substituent, and a basic substituent It is possible to produce an acridone derivative having a triazine derivative having a basic substituent.

(Examples 11 to 20) <Production of pigment composition>
As shown in Table 3, pigments (CI Pigment Blue 15: 3), dispersants 1 to 10 synthesized in Examples 1 to 10, and dyes having basic substituents synthesized in Production Examples 1 to 10 Derivatives 1 to 10 and methoxypropyl acetate were blended, 100 parts of 2 mmφ zirconia beads were added and dispersed for 3 hours with a paint conditioner to prepare pigment compositions 1 to 10.

(Comparative Examples 5 to 8) <Production of pigment composition>
Pigment compositions 11 to 14 were prepared in the same manner as in Examples 11 to 20, except that the comparative dispersants 1 to 4 having carboxyl groups synthesized in Comparative Examples 1 to 4 were used.

(Evaluation of pigment compositions 1-14)
In order to evaluate the performance of the pigment composition of the present invention, the viscosity of the obtained composition was measured with a B-type viscometer (25 ° C., rotation speed 100 rpm), and the haze was measured with a haze meter (light transmittance 20%). The performance of the dispersion was evaluated by initial viscosity and haze (the lower the viscosity, the better the haze, the lower the haze, the better). The initial viscosity and haze were measured after standing at room temperature for 1 day after dispersion, and the time-lapse viscosity was measured after standing at 50 ° C. for 1 week. The results are shown in Table 3.

As is clear from the above evaluation results, the pigment compositions 1 to 15 of Examples 16 to 30 using the dispersants 1 to 15 produced in Examples 1 to 15 of the present invention have a low initial viscosity, and It shows good stability with little increase in viscosity over time. Furthermore, the haze is low. On the other hand, in the pigment compositions 16 to 19 of Comparative Examples 5 to 8 using the comparative dispersants 1 to 4 produced in Comparative Examples 1 to 4, both the viscosity and the haze are high, and the viscosity with time is increased. It was found that there was a problem with dispersibility.

(Example 31) <Production of pigment composition>
10 parts (solid content 0.5 parts) of the dispersant of Example 1, 40 parts of ATO powder (spherical particles, primary particle diameter 20 nm), 50 parts of methoxypropyl acetate and 100 parts of 2 mmφ zirconia beads were added, and paint conditioner was added. Was dispersed for 3 hours to prepare a pigment composition 15 having a solid content of 50%.

(Examples 32 to 35) <Production of pigment composition>
Except having produced with the composition shown in Table 4, it carried out similarly to Example 31, and produced the pigment compositions 20-24 of 50% of solid content.

(Comparative Examples 9 to 12) <Production of pigment composition>
Except having produced with the composition shown in Table 4, it carried out similarly to Example 31, and produced the pigment compositions 25-28 of 50% of solid content.

(Evaluation of pigment compositions 20 to 28)
In order to evaluate the performance of the pigment compositions 20 to 28 of the present invention, the viscosity of the obtained composition was measured with a B-type viscometer (25 ° C., rotation speed 100 rpm), and the haze was measured with a haze meter. The performance of the dispersion was evaluated by haze (the lower the viscosity, the better. The smaller the haze, the better). The initial viscosity and haze were measured after standing at room temperature for 1 day after dispersion, and the time-lapse viscosity was measured after standing at 50 ° C. for 1 week. The results are shown in Table 4.
ATO: Tin oxide containing antimony ITO: Tin containing indium oxide PTO: Phosphorus containing tin oxide GZO: Gallium containing zinc oxide

  As is apparent from the above evaluation results, the pigment compositions 20 to 24 of Examples 31 to 35 using the dispersant of the present invention have a low initial viscosity and a good stability with little increase in viscosity over time. Is shown. Furthermore, the haze is low. On the other hand, in the pigment compositions 25 to 28 of Comparative Examples 9 to 12 using the comparative dispersants 1 to 4, the viscosity or haze is high, and the viscosity may increase with time, and there is a problem with dispersibility. I found out that

Claims (9)

3 or more in one end region obtained by radical polymerization of ethylenically unsaturated monomer (b) in the presence of compound (a) having 3 or more hydroxyl groups and one thiol group in the molecule Hydroxyl groups in the vinyl polymer (A) having the hydroxyl groups of
An acid anhydride group of the carboxylic acid anhydride (c);
Dispersant for pigment produced by reacting. A hydroxyl group in the compound (a) having three or more hydroxyl groups and one thiol group in the molecule;
An acid anhydride group in the carboxylic acid anhydride (c);
A dispersant for pigments produced by radical polymerization of an ethylenically unsaturated monomer (b) in the presence of a compound having a carboxyl group and a thiol group obtained by reacting.   The dispersant for pigment according to claim 1 or 2, wherein the carboxylic anhydride (c) is a tricarboxylic anhydride or a tetracarboxylic dianhydride. The dispersant for pigment according to any one of claims 1 to 3, wherein the tetracarboxylic acid anhydride is represented by the following general formula (1) or general formula (2).
General formula (1)


[In General Formula (1), k is 1 or 2. ]
General formula (2)


[In General Formula (2), R ¹ represents a direct bond, —O—, —CO—, —COOCH ₂ CH ₂ OCO—
_{, -SO 2 -, - C (} CF 3) 2 -, wherein:


Or a group represented by the formula:


It is group represented by these. ]
The dispersant for pigment according to any one of claims 1 to 3, wherein the tricarboxylic acid anhydride is represented by the following general formula (3).
General formula (3)


[In General Formula (3), k is 1 or 2. ]
The dispersant for pigments according to any one of claims 1 to 5, wherein the ethylenically unsaturated monomer contains a monomer represented by the following general formula (4).
General formula (4)


[In General Formula (4), R ² is a linear or branched alkyl group having 1 to 4 carbon atoms or an alicyclic alkyl group having 6 to 15 carbon atoms. ]   The dispersant for pigments according to any one of claims 1 to 6, wherein the vinyl polymer portion obtained by radical polymerization of an ethylenically unsaturated monomer has a weight average molecular weight of 1,000 to 10,000.   The pigment composition containing the dispersing agent for pigments as described in any one of Claims 1-7, and a pigment (P).   A pigment dispersion obtained by dispersing the pigment composition according to claim 8 in a varnish.