JPH09194585A - Pigment dispersant, its production and composition containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pigment dispersant for coating material, ink, etc., by reacting a polycarbonate compound containing a unit produced by ring opening of a cyclic carbonate compound and having a functional group capable of carrying out Mickel addition with an amino group at one end with a polyamine. SOLUTION: A polycarbonate compound represented by formula II (X is a unit having a functional group capable of carrying out Michel addition reaction with an amino group; Y is a unit having a polycarbonate chain containing a unit produced by ring opening of a cyclic carbonate represented by formula I as a component; R is a 1-20C alkyl, an aromatic group, OH, cyano or a halogen) and containing a unit produced by ring opening of a cyclic carbonate compound represented by formula I [R<1> is a 1-10C (substituted)aliphatic alkylene] (e.g. 2,2-dimethyltrimethylene carbonate) as a component and having a functional group capable of reacting carrying out Mickel addition reaction with an amino group at one end is subjected to Mickel addition reaction with a polyamine compound (e.g. polyethyleneimine) to provide the objective pigment dispersant.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pigment dispersant and a method for producing the same. More specifically, it relates to a pigment dispersant used for the purpose of improving the dispersibility of a pigment when preparing a coating material, a printing ink, etc., a method for producing the same, and a composition containing the same.

[0002]

2. Description of the Related Art Conventionally, when preparing paints, printing inks, etc., the dispersibility of the pigments contained therein is improved, the storage stability of the paints, the dispersion time is shortened, the phenomenon of color separation is prevented, and the coating film is Various dispersants are used for the purpose of improving the glossiness of the. The dispersant used for this purpose is generally a compound having a structure having a portion that is adsorbed by a pigment and a portion that is compatible with a vehicle for paints or inks. The compounds conventionally used for this purpose are compounds having a polyester component and / or a polycaprolactone component in the molecular chain. It is known that the polyester component contained in the molecular chain has high compatibility with the vehicle. However, for example, a polycaprolactone component obtained by ring-opening polymerization of a lactone compound has high crystallinity, and there is a problem that it crystallizes in a vehicle in winter.

Various functional groups are used as a group that is easily adsorbed to a pigment (hereinafter sometimes referred to as "adsorption group"), and many dispersants having an amino group in the molecular chain are known. There is. For example, JP-A-53-103988 discloses low molecular weight amino compounds such as N, N-dimethylaminopropylamine and JP-A-61-174939.
The publication discloses a pigment dispersant using polyethyleneimine which is a high molecular weight amine compound.

[0004]

In these pigment dispersants, the polyester component contained in the molecular chain and the polyamines are bound by an amide bond. However, the compound having an amide bond has a very high cohesive force, and when used as a pigment dispersant, it has a drawback that it is difficult to dissolve in many paint solvents. Further, the amide-bonded nitrogen atom portion has extremely low basicity, and therefore the amide-bonded nitrogen does not exhibit adsorptivity to the pigment. Furthermore, when an effective steric repulsion layer is formed on the surface of the pigment and a large amount of polyester chain is grafted to the polyamine for the purpose of improving the dispersion stability of the pigment,
There is a problem that the amount of adsorbing groups decreases, and conversely the dispersibility decreases.

Furthermore, in the case where a component having a polyester chain in the molecule is graft-reacted with a polyamine, a reaction temperature of at least 100 to 150 ° C. is necessary to obtain an appropriate reaction rate. When the reaction composition containing amines is heated at such a reaction temperature,
In many cases, the coloration of the reaction product is unavoidable, and there is a drawback that the coating film is colored pale yellow in the case of a light-colored paint, especially white. The present invention provides a pigment dispersant having good compatibility with a wide range of resins and exhibiting extremely good dispersion performance with respect to a wide range of pigments, a method for producing the same, and a composition containing the same. The purpose is to do.

[0006]

In view of the present situation, the present inventor has conducted diligent studies to solve the above problems and problems. As a result, a polycarbonate compound having a specific functional group at one end is replaced with a polyamine compound by Michael. It was found that the reaction product obtained by the addition reaction can solve the above problems and problems, and the present invention has been completed.

That is, according to the first aspect of the present invention, a unit formed by ring-opening of the cyclic carbonate compound represented by the general formula (1) is contained as a structural component, and an amino group and a Michael addition reaction are formed at one end. Provided is a pigment dispersant obtained by subjecting a polycarbonate compound represented by the general formula (2) having a possible functional group to a Michael addition reaction of a polyamine compound.

Embedded image

Embedded image

The second aspect of the present invention is a functional group which contains as a structural component a unit formed by ring-opening of a cyclic carbonate compound represented by the general formula (1), and has one end capable of undergoing a Michael addition reaction with an amino group. There is provided a method for producing a pigment dispersant, which comprises preparing a polycarbonate compound represented by the general formula (2) having a group, and then subjecting the polycarbonate compound and a polyamine compound to a Michael addition reaction.

Embedded image

Embedded image According to a third aspect of the present invention, there is provided a printing ink composition containing the pigment dispersant. Hereinafter, the present invention will be described in detail.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The pigment dispersant according to the present invention is obtained by using a specific polycarbonate compound and a polyamine compound as raw materials and subjecting them to a Michael addition reaction.

(Polycarbonate compound) The first aspect of the present invention
The polycarbonate compound, which is a raw material component of the pigment dispersant according to (1), is represented by the general formula (2), contains a polycarbonate skeleton obtained by ring-opening polymerization of the cyclic carbonate compound represented by the general formula (1), and , A polycarbonate polymer and / or a polyester / polycarbonate copolymer having a functional group capable of addition reaction with an amino group at one end.

The polycarbonate polymer and / or polyester / polycarbonate copolymer having a functional group capable of undergoing a Michael addition reaction with the amino group at one end is
It can be synthesized by various methods. Those having a (meth) acryloyl group as a functional group (X) capable of undergoing a Michael addition reaction with an amino group only at one end of a chain of a polycarbonate polymer or a polyester / polycarbonate copolymer are synthetic and reactive. It is convenient. The (meth) acryloyl group means a methacryloyl group and an acryloyl group.

A polycarbonate polymer or a polyester / polycarbonate copolymer having a (meth) acryloyl group only at one end can be synthesized by the following reaction. (A) Addition reaction of a cyclic carbonate compound to a (meth) acrylic acid ester containing a hydroxyl group (hydroxyl group). (B) An insertion reaction utilizing a transesterification reaction between a (meth) acrylic acid ester and a cyclic carbonate compound. (C) Addition reaction of a polycarbonate polymer or a polyester-polycarbonate copolymer having a carboxyl group at one end with an epoxy group-containing (meth) acrylate such as glycidyl methacrylate. Hereinafter, these reaction methods will be described.

The hydroxyl group-containing (meth) acrylic acid ester which can be used in the addition reaction of the first (a) hydroxyl group-containing (meth) acrylic acid ester with the cyclic carbonate compound is hydroxyethyl (meth) acrylate, Examples thereof include a hydroxy group-containing (meth) acrylic acid ester represented by the following general formula (5) such as hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate.

[0014]

Embedded image

Preferred cyclic carbonate compounds include 6-membered cyclic carbonates such as trimethylene carbonate, 2-methyl-trimethylene carbonate and 2,2-dimethyltrimethylene carbonate. In addition, when the cyclic carbonate compound is subjected to addition polymerization, the melting point of the polycarbonate produced can be lowered by copolymerizing the lactone represented by the following general formula (3), and finally obtained. The compatibility of the pigment dispersant with the vehicle can be further improved.

[0016]

Embedded image

Examples of the substituent of R ² of the lactone compound (3) that can be copolymerized with the cyclic carbonate compound include lower alkyl groups such as methyl group, and specific examples of the lactone compound include , Ε-caprolactone, δ-valerolactone, β-methyl-δ-valerolactone, 4-methylcaprolactone, 2-methylcaprolactone, β-propiolactone, γ-butyrolactone and the like. These may be used alone or as a mixture of two or more kinds. Among them, lactones having a side chain (substituent) destroy the crystallinity of the polyester / polycarbonate copolymer chain, and are excellent in compatibility with resins and solubility in solvents, which reduces the viscosity of the mill base and reduces the temperature at low temperatures. It is preferable because the stability of the coating composition is excellent.

In the addition reaction (a), the raw material hydroxyl group-containing (meth) acrylate, a cyclic carbonate compound, and lactones that are added as necessary are charged into a reactor equipped with a condenser, a stirrer, an air introduction pipe, and the like. It can be obtained by charging, stirring, if necessary, a catalyst, and heating to react. The reaction temperature varies depending on the type and ratio of raw materials, presence or absence of catalyst, type and amount, type and amount of solvent, and the like, but is selected in the range of 20 to 150 ° C. At 20 ° C. or lower, the reaction is extremely slow, and at 150 ° C. or higher, polymerization of only the hydroxyl group-containing (meth) acrylate occurs and the desired product cannot be obtained, which is not preferable. Particularly preferable temperature range is 40 to 120 ° C.

Examples of the catalyst that can be used in the addition reaction (a) include titanium-based catalysts such as tetrabutyl titanate and tetraisopropyl titanate, and tin-based catalysts such as stannous chloride, tin octylate and monobutyltin oxide. Acid catalysts such as p-toluenesulfonic acid and the like. The amount of catalyst used depends on the type and ratio of raw materials,
Depending on the type and amount of solvent, reaction temperature, etc.,
It is selected in the range of 3,000 ppm. The amount of catalyst is 3,000
If it exceeds 0 ppm, coloring of the product becomes severe and the quality of the product is adversely affected, which is not preferable. A particularly preferred amount of catalyst is in the range of 1 to 100 ppm.

When carrying out the addition reaction (a), it is desirable to allow a small amount of a polymerization inhibitor to be present in the reaction system in order to prevent the polymerization of only the hydroxyl group-containing (meth) acrylate. Examples of the polymerization inhibitor include known polymerization inhibitors such as hydroquinone, methylhydroquinone and phenothiazine. Further, in order to prevent the polymerization of (meth) acrylates, it is desirable that a slight amount of oxygen be present in the reaction system.

Next, (b) the insertion reaction utilizing the transesterification reaction between the (meth) acrylic acid ester and the cyclic carbonate compound will be described. The (meth) acrylic acid ester that can be used in this insertion reaction is a compound represented by the following general formula (6), and specifically, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) Examples thereof include butyl acrylate and octyl (meth) acrylate.

[0022]

Embedded image

The cyclic carbonate compound that can be used in the insertion reaction (b) is preferably trimethylene carbonate, 2-methyl-trimethylene carbonate,
Examples include 6-membered ring carbonates such as 2,2-dimethyltrimethylene carbonate. In addition, when the cyclic carbonate compound is subjected to addition polymerization, the melting point of the polycarbonate produced can be lowered by copolymerizing the lactone represented by the general formula (3), and finally obtained. The compatibility of the pigment dispersant with the vehicle can be further improved. Specifically, ε−
Caprolactone, δ-valerolactone, β-methyl-δ
-Valerolactone, 4-methylcaprolactone, 2-methylcaprolactone, β-propiolactone, γ-butyrolactone and the like can be mentioned. These may be used alone or as a mixture of two or more kinds. Among them, lactones having a side chain disrupt the crystallinity of the polyester / polycarbonate copolymer chain, and are excellent in compatibility with resins and solubility in solvents, which reduces the viscosity of the millbase and stabilizes the paint at low temperatures. It is preferable because it has excellent properties.

The insertion reaction (b) is carried out by using the (meth) raw material.
Acrylic ester, cyclic carbonate, and lactones that may be used are charged into a reactor equipped with a dehydration tube, a condenser, a stirrer, etc., and a catalyst is added under stirring, if necessary, and heated to react. To be The reaction temperature is the type and ratio of raw materials, the presence or absence of a catalyst, the type and amount,
Although it varies depending on the kind and amount of the solvent, it is selected from the range of 50 to 150 ° C. Below 50 ℃, the reaction is extremely slow,
Further, at 150 ° C. or higher, polymerization of only the (meth) acrylic acid ester occurs, and the intended product cannot be obtained, either of which is not preferable. Especially preferred in the above temperature range is 80 to 120.
It is in the range of ° C.

The types of catalysts that can be used in carrying out the addition reaction of (b) are the same as those mentioned in the description of the addition reaction of (a) above. The amount of catalyst used depends on the type of raw material,
Depending on the ratio, type of solvent, amount, reaction temperature, etc.,
It is selected in the range of 0.1 ppm to 1%. When the amount of the catalyst exceeds 1%, coloring of the product becomes severe and the quality of the product is adversely affected, which is not preferable. A particularly preferred amount of catalyst is in the range of 1 ppm to 1,000 ppm.

In carrying out the addition reaction (b), it is desirable that a small amount of a polymerization inhibitor be present in the reaction system in order to prevent the polymerization of only the (meth) acrylic acid ester.
The type of polymerization inhibitor that can be used at this time is as described in (a) above.
It is the same as that described in the explanation of the addition reaction of, and it is also the same that it is desirable to make a minute amount of oxygen exist in the reaction system.

The addition reaction of (c) a polycarbonate polymer or polyester-polycarbonate copolymer having a carboxyl group at one end with an epoxy group-containing (meth) acrylate such as glycidyl methacrylate will be described. Having a carboxyl group at one end,
The polycarbonate polymer or the polyester-polycarbonate copolymer can be synthesized by a reaction of adding a cyclic carbonate compound to monocarboxylic acids or a reaction of adding a cyclic carbonate compound to hydroxylcarboxylic acids.

The polycarbonate compound which can be used in the addition reaction (c) is preferably a polymer of a cyclic carbonate compound, and the cyclic carbonate compound is the same kind as the one mentioned in the description of the addition reaction in the above (a), Also,
When polymerizing these cyclic carbonate compounds, the melting point of the polycarbonate compound produced can be lowered by copolymerizing lactones to form a polyester / polycarbonate copolymer, and the pigment dispersant finally obtained. It is also the case that the compatibility with the vehicle can be further improved.

The lactone compound which can be copolymerized with the cyclic carbonate compound is represented by the above general formula (3)
The lactones are represented by the following, and specific examples thereof are the same as those mentioned in the description of the addition reaction in (a) above. Among them, the fact that lactones having a side chain are preferable is the same as described in the above section.

Carboxyl group-terminated polycarbonate compounds include polycarbonate polymers or polyester / polycarbonate copolymers, dicarboxylic acids, diol components, lactone compounds, hydroxycarboxylic acid compounds,
It can also be synthesized by reacting a raw material such as a monocarboxylic acid compound, a divalent or higher carboxylic acid or an acid anhydride thereof.

Examples of the monocarboxylic acid compound that can be used in the addition reaction (c) include various aliphatic and aromatic carboxylic acids. Specific examples thereof include acetic acid, propionic acid, butyric acid, valeric acid, trimethylacetic acid, caproic acid, lauric acid, stearic acid, abietic acid, phenyl acid and methoxyacetic acid. These may be used alone or as a mixture of two or more.

The hydroxycarboxylic acid which can be used in the addition reaction (c) includes aliphatic, aromatic and unsaturated hydroxycarboxylic acids. Specifically, ricilenic acid, ricinoleic acid, 12-hydroxystearic acid, castor oil fatty acid, hydrogenated castor oil fatty acid, δ
-Hydroxyvaleric acid, ε-hydroxycaproic acid, P-
Hydroxyethyloxycarboxylic acid, 2-hydroxynaphthalene-3-carboxylic acid, 2-hydroxynaphthalene-6-carboxylic acid, 2,2-dimethylolpropionic acid, 2,2-dimethylolvaleric acid, 2,2-dimethylolpentane Examples thereof include acids, malic acid, tartaric acid, lactic acid, glycolic acid, gluconic acid, hydroxypivalic acid, 11-oxyhexadecanoic acid, 2-oxidedecanoic acid, salicylic acid and the like. These may be used alone or as a mixture of two or more.

In the reaction of adding the cyclic carbonate compound to the monocarboxylic acid, a carboxylic acid-modified polycarbonate compound having a higher molecular weight than a predetermined molecular weight or a high molecular weight homopolymer of the cyclic carbonate compound is used depending on the molar ratio of the initiator to the cyclic carbonate compound. A monocarboxylic acid may be obtained. On the other hand, when hydroxycarboxylic acid is used as an initiator, a polycarbonate compound having a predetermined molecular weight can be easily obtained.

Further, it can be used in the addition reaction of (c) 2
Examples of the carboxylic acid having a valency or more or its acid anhydride include maleic acid, succinic acid, glutaric acid, fumaric acid, adipic acid, sebacic acid, mazelaic acid, dodecane diacid, phthalic acid, isophthalic acid, terephthalic acid, hexahydrophthalic acid Examples thereof include acid, methylhexahydrophthalic acid, tetrahydrophthalic acid, trimellitic acid, methyltetrahydrophthalic acid, and their anhydrides.

Examples of the polyhydric alcohol that can be used in the addition reaction (c) include various alcohols such as an aliphatic branched or linear structure, or an alicyclic or aromatic alcohol. Specifically, ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,2-propylene glycol, 1,3-butylene glycol,
1,4-butylene glycol, neopentyl glycol, 3-methylpentanediol, 1,5-pentanediol, 1,6-hexanediol, trimethylolpropane, cyclohexanedimethanol, 1,4-dibenzyl alcohol and the like can be mentioned. .

To synthesize the carboxyl group-terminated polyester compound, the polyester raw material is charged into a reactor equipped with a dehydration tube, a condenser, a stirrer and the like, and the reaction is carried out under an inert gas stream such as nitrogen gas. . A suitable dehydrating solvent such as toluene or xylene can also be used in this synthesis reaction. The solvent used in the reaction may be removed by an operation such as distillation after the reaction is completed, or may be directly used as a part of the finally obtained product.

The reaction temperature for synthesizing the carboxyl group-terminated polycarbonate compound can be selected in the range of 120 to 220 ° C. When the reaction temperature is 120 ° C. or lower, the reaction rate is extremely slow, and when it is 220 ° C. or higher, side reactions other than addition reaction, such as decomposition of a polycarbonate polymer into a cyclic monomer, formation of an ether bond by decarboxylation reaction, and cyclic carbonate dimer Is easily generated, it is difficult to synthesize a carboxyl group-terminated polycarbonate compound having a target molecular weight, and the product is strongly colored, which is not preferable. Particularly preferred in the above temperature range is 16
It is 0 to 210 ° C.

Esterification catalysts that can be used when synthesizing a carboxyl group-terminated polycarbonate compound include
Organotin compounds such as tin octylate, dibutyltin oxide, dibutyltin laurate, monobutyltin hydroxybutyl oxide, stannous oxide, tin compounds such as stannous chloride, tetrabutyl titanate, tetraethyl titanate, tetrapropyl titanate, etc. Can be mentioned. The amount of the catalyst used can be selected in the range of 0.1 to 3,000 ppm. When the amount of the catalyst is 0.1 ppm or less, the ring-opening polymerization rate of the cyclic carbonate compound and the lactone becomes extremely slow, and the amount of the catalyst is 3,000.
When it is more than ppm, the coloring of the product becomes severe and the quality of the product is adversely affected.
A particularly preferred range for the amount of catalyst is 1-100 ppm. Further, when the synthesis reaction is performed in the presence of air, the product tends to be colored, so it is desirable to perform it in an atmosphere of an inert gas such as nitrogen gas.

The carbosyl-terminated polycarbonate obtained by the above reaction is then reacted with an epoxy group-containing (meth) acrylate. Examples of the epoxy group-containing (meth) acrylate include compounds represented by the following general formula (7). Glycidyl methacrylate, β-methylglycidyl methacrylate, 2,3-epoxycyclohexylmethyl (meth) acrylate and the like are industrially produced and easily available.

[0040]

Embedded image

The above reaction is obtained by charging the epoxy group-containing (meth) acrylate, the polycarbonate polymer or the polyester-polycarbonate copolymer into a reactor equipped with a dehydration tube, a condenser, a stirrer, etc., and reacting them. To be The temperature at this time is
It may be selected in the range of 50 to 150 ° C., though it varies depending on the type and ratio of raw materials, presence or absence of catalyst, type and amount, presence or absence of solvent, type and amount. When the temperature is 50 ° C or lower, the reaction rate is extremely slow, and when it is 150 ° C or higher, the epoxy group is contained (meta)
Polymerization of the acrylate itself occurs, and the target compound cannot be obtained, either of which is not preferable. Particularly preferred in the above temperature range is 80 to 120 ° C.

The catalyst that can be used in the above reaction is
Amine catalysts such as N, N-dimethylbenzylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, triphenylphosphine, halogen ion salts of tetraphenylphosphonium, ethyltri Examples thereof include phosphorus-based catalysts such as halogen ion salts of phenylphosphonium.

The amount of the catalyst used varies depending on the type and ratio of raw materials, the presence or absence of a solvent, the type and amount, the reaction temperature, etc.
It can be selected in the range of up to 3,000 ppm. When the amount of the catalyst is 3,000 ppm or more, coloring of the obtained product becomes severe and the quality of the finally obtained product is adversely affected, which is not preferable. A particularly preferred amount of catalyst is 1 to 500 ppm.

When carrying out the above reaction, it is desirable to allow a small amount of a polymerization inhibitor to be present in the polymerization system in order to prevent the polymerization of only the epoxy group-containing (meth) acrylate. Examples of the polymerization inhibitor include known polymerization inhibitors such as hydroquinone, ethylhydroquinone and phenothiazine. Further, in order to prevent the polymerization of only the epoxy group-containing (meth) acrylate, it is desirable to carry out the reaction in the presence of a slight amount of oxygen in the polymerization system.

In addition to these methods, first, a monofunctional polycarbonate polymer or polyester-polycarbonate copolymer having one hydroxyl group is synthesized, and then reacted with a bifunctional isocyanate to synthesize a prepolymer, It is also possible to react the obtained prepolymer with a hydroxyl group-containing (meth) acrylate to prepare a raw material for the dispersant. However, in this case, a reaction product of a monofunctional polycarbonate polymer or polyester-polycarbonate copolymer having one 2 mol hydroxyl group and 1 mol diisocyanate is likely to be mixed as an impurity. In addition, when unreacted isocyanate remains, a cross-linking reaction may occur when reacting with the polyamine compound in the next step, and a gel substance may be mixed in the product.

According to the experiments conducted by the present inventors, the average molecular weight of the polycarbonate polymer or polyester / polycarbonate copolymer portion contained in the dispersant thus synthesized is in the range of 100 to 20,000. It turned out to be preferable. When the average molecular weight is 100 or less, a sufficient three-dimensional repulsion layer cannot be formed around the pigment particles,
Further, if the average molecular weight is 20,000 or more, the molecular weight of the entire dispersant becomes too large, the compatibility with the paint or the vehicle for the printing ink is lowered, and the pigment dispersibility is also lowered, which is not preferable either. A particularly preferable average molecular weight is in the range of 500 to 10,000. The average molecular weight of the polycarbonate polymer or polyester / polycarbonate copolymer portion here refers to the value measured by the NMR method. These can be easily obtained from the integral value of the terminal group and the main chain portion of the polyester / polycarbonate copolymer or polycarbonate.

Polycarbonate compounds and polyester-polycarbonate copolymers, which are synthesized in this manner and which are reacted with a polyamine compound to form a dispersant, are represented by the following general formula (4).

[0048]

Embedded image

(Polyamine Compound) Next, the polycarbonate compound is reacted with a polyamine compound to synthesize a pigment dispersant. The polyamine compound used in the present invention preferably has a molecular weight in the range of 100 to 100,000. When the molecular weight is 100 or less, the molecular weight of the adsorbed portion of the pigment is too low to use the effect of using the polyamine compound, and when the molecular weight is 100,000 or more, the overall molecular weight of the pigment dispersant becomes too large. It may invite meetings and reduce the dispersion. In addition, the viscosity of the dispersant when melted is high and synthesis is difficult.

Specific examples of such a high molecular weight polyamine compound include polyethyleneimine, polyallylamine and polyvinylamine. To improve the compatibility with paint resins and the solubility with solvents, monoepoxides of α-olefins, reaction products of monoepoxides such as glycidyl epoxy of versatic acid with polyamine compounds, and methyl (meth) It is also possible to use polyamines modified with acrylate monomers such as acrylate, butyl (meth) acrylate, hydroxyethyl (meth) acrylate, cyclohexyl (meth) acrylate.

(Michael Addition Reaction) In the Michael addition reaction, the above polyamine and the above-mentioned polycarbonate compound (polyester copolymer having a functional group capable of Michael addition at one end) are used as raw materials. Regarding the ratio of the raw materials in the addition reaction, it is desirable to select the molar ratio of the functional group capable of Michael addition to the amino group in the range of 1: 1 to 1:99, and more preferably 2: 3 to 1:65. Is the range.

In order to carry out the Michael addition reaction, the above raw materials are charged in a reactor equipped with a dehydration tube, a condenser, a stirrer and the like, and heated to react.
The reaction temperature is 10 to 130 because it proceeds rapidly and almost quantitatively with some heat generation even at room temperature.
Can be selected in the range of ° C. At 10 ° C or lower, the reaction is slow and an industrially reasonable reaction rate cannot be obtained, and at 130 ° C or higher, problems such as reaction between functional groups capable of Michael addition and coloring of reaction products are likely to occur. , Neither is preferable. 20-100 degreeC is preferable in the said temperature range.

For the Michael addition reaction, a solvent that does not participate in the addition reaction can be used. Such solvents include xylene, toluene, aromatic solvents such as Solvesso, ketones such as anone, methyl ethyl ketone, and methyl isobutyl ketone, alcohols such as butanol and isopropanol, dimethyl adipate, dimethyl succinate, and dimethyl glutarate. Esters may be mentioned. The solvent used in the reaction can be removed by an operation such as distillation after the reaction is completed, or can be used as it is as a part of the final product.

According to the experiments of the present inventor, the pigment dispersant thus synthesized has an amine value of 10 to 500.
It has been found that a range of mgKOH / g is preferred. If the amine value is less than 10 mgKOH / g, the amount of amino groups adsorbed on the pigment is too small and the effect as a dispersant is low. Both are not preferable because the polymer portion is too small to impair the dispersion stability, or the thermosetting coating system may hinder the curing reaction. Here, the amine value means a value measured by a neutralization titration method with hydrochloric acid.

(Method of Using Pigment Dispersant) In the pigment dispersant thus synthesized, when the end of the polyester chain in the dispersant opposite to the amino group is terminated with a hydroxyl group, In the baking process after coating,
By reacting with the melamine resin or the isocyanate, the present pigment dispersant is firmly incorporated as a part of the coating film. As a result, bleeding or crystallization of the pigment dispersant in the coating film does not occur, and the pigment captured by the pigment dispersant is less likely to bleed or re-aggregate in the coating film. Furthermore, by using a lactone compound-containing polyester / polycarbonate copolymer having an appropriate molecular weight as a reaction intermediate, it can be applied to pigment dispersion using a solvent having relatively high polarity such as alcohol and cellosolves. it can.

The pigment dispersant according to the first aspect of the present invention is a pigment,
It can be used as a coating composition or a printing ink composition after being mixed with other additives and dispersed by a known method. That is, by mixing the content, the dispersant, the coating resin and especially the organic solvent in the given order,
A coating composition and a printing ink composition can be obtained. The pigment dispersant of the present invention, when used for these applications,
Since the pigment has an adsorbing group that is easily absorbed, the adsorption performance is sufficient, and thus the dispersibility of the pigment, the fluidity of the mill base, the storage stability of the pigment dispersion, and the like can be improved.

Examples of the pigment that can be used in combination with the pigment dispersant according to the first aspect of the present invention include inorganic pigments and organic pigments. As the inorganic pigment, titanium oxide, zinc oxide,
Examples thereof include cadmium sulfide, yellow iron oxide, red iron oxide, yellow lead, and carbon black. Examples of organic pigments include phthalocyanines, insoluble azo pigments, azo lake pigments, condensed polycyclic pigments (threne type, indigo type, perillin type, perinone type, phthalone type, dioxazine type, quinacridone type, isoindolinone type, diketopyrrolone type Pyrrole pigment) and the like.

As the paint resin which can be used in combination with the present dispersant, general paint resins can be preferably used. However, alkyd resin, oil-free alkyd resin, epoxy resin, acrylic resin, urethane resin, melamine resin, Examples include guanamine resin and urea resin. Examples of other additives include leveling agents and defoaming agents. Examples of the magnetic material include metallic compounds having magnetism such as ferrite.

[0059]

EXAMPLES The present invention will be described in detail below with reference to synthesis examples, examples, comparative examples, and application examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. . In addition, "part" and "%" in the description examples both mean weight standards.

In the following description examples, the analysis of the intermediates obtained in the synthesis examples and the analysis of the dispersants obtained in the examples and comparative examples are based on the method described below. (1) Analysis of amount of unreacted carbonate monomer in reaction system: analysis by gas chromatograph (2) Analysis of amount of unreacted caprolactam monomer in reaction system: analysis by gas chromatograph (3) Acid value: medium with potassium hydroxide aqueous solution Japanese titration method (4) Amine value: Neutralization titration method with diluted hydrochloric acid (5) Hue: Colorimetric analysis method by APHA method

(Synthesis Example) (1) Synthesis of "Intermediate 1": In a glass flask having a capacity of 2 liters equipped with a stirrer, a Dimroth condenser, a thermometer, and an air inlet tube, 116 parts of hydroxyethyl acrylate, ε- 442 parts of caprolactone, 442 parts of dimethyltrimethylene carbonate, 5 parts of p-toluenesulfonic acid and 1.3 parts of methylhydroquinone were charged. While introducing air into the flask, the internal temperature was raised to 50 ° C. with stirring and the reaction was carried out at this temperature for 15 hours. Furthermore, the reaction was continued until the dimethyltrimethylene carbonate monomer remaining in the reaction system became 3% or less. The molecular weight of the obtained product was 1,000. Hereinafter, this product is referred to as "intermediate 1".

(2) Synthesis of "intermediate 2": "intermediate 1"
In the same glass flask that was used in the synthesis of, hydroxyethyl acrylate 116 parts, ε-caprolactone 6
92 parts, dimethyl trimethylene carbonate 692 parts,
7.5 parts of p-toluenesulfonic acid and 1.8 parts of methylhydroquinone were charged. While introducing air into the flask, the internal temperature was raised to 50 ° C. with stirring and the reaction was carried out at this temperature for 15 hours. Furthermore, the reaction was continued until the dimethyltrimethylene carbonate monomer remaining in the reaction system became 3% or less. The molecular weight of the obtained product is 15
It was 00. Hereinafter, this product is referred to as "intermediate 2".

(3) Synthesis of "Intermediate 3": A 3-liter glass flask equipped with a stirrer, Dimroth condenser, thermometer, and air inlet tube was charged with 116 parts of hydroxyethyl acrylate and 942 parts of ε-caprolactone. 942 parts of dimethyl trimethylene carbonate, 10 parts of p-toluenesulfonic acid, and 2.5 parts of methylhydroquinone were charged, respectively. While introducing air into the flask, the internal temperature was raised to 50 ° C. with stirring and the reaction was carried out at this temperature for 15 hours. Furthermore, the reaction was continued until the dimethyltrimethylene carbonate monomer remaining in the reaction system became 3% or less. The molecular weight of the obtained product was 2,000. Hereinafter, this product is referred to as "intermediate 3".

(4) Synthesis of "Intermediate 4": In a glass flask having a capacity of 5 liters equipped with a stirrer, a Dimroth condenser, a thermometer, and an air inlet tube, 116 parts of hydroxyethyl acrylate, 1710 parts of ε-caprolactone,
1384 parts of trimethylene carbonate, 7.5 parts of p-toluenesulfonic acid, 2.0 parts of methylhydroquinone,
I prepared each. While introducing air into the flask, the internal temperature was raised to 50 ° C. with stirring and the reaction was carried out at this temperature for 15 hours. Furthermore, the reaction was continued until the amount of trimethylene carbonate monomer remaining in the reaction system was 3% or less. The molecular weight of the obtained product was 1500. Hereinafter, this product is referred to as "intermediate 4".

(5) Synthesis of "intermediate 5": "intermediate 3"
To the same glass flask used in the synthesis of 1), 116 parts of hydroxyethyl acrylate, 1384 parts of 2-methyltrimethylene carbonate, 7.5 parts of p-toluenesulfonic acid, and 2.1 parts of methylhydroquinone were charged. While introducing air into the flask, the internal temperature was raised to 100 ° C. with stirring and the reaction was carried out at this temperature for 15 hours. Further, the reaction was continued until the 2-methyltrimethylene carbonate monomer remaining in the reaction system became 3% or less. The molecular weight of the obtained product was 1500. Hereinafter, this product is referred to as "intermediate 5".

(6) Synthesis of "intermediate 6": "intermediate 3"
In the same glass flask used in the synthesis of the above, 116 parts of hydroxyethyl acrylate, 692 parts of dimethyl trimethylene carbonate, 554 parts of ε-caprolactone,
138 parts of 4-methylcaprolactone, 7.5 parts of p-toluenesulfonic acid, and 2.1 parts of methylhydroquinone were charged. While introducing air into the flask, the internal temperature was raised to 100 ° C. with stirring and the reaction was carried out at this temperature for 10 hours. Furthermore, the reaction was continued until the dimethyltrimethylene carbonate monomer remaining in the reaction system became 3% or less. Hereinafter, this product is referred to as "intermediate 6".

(7) Synthesis of "intermediate 7": "intermediate 1"
In the same glass flask used in the synthesis of, 592 parts trimethylene carbonate, ε-caprolactone 592
Parts, 134 parts of dimethylolpropionic acid, and 3 parts of p-toluenesulfonic acid were charged. While introducing air into the flask, the internal temperature was raised to 90 ° C. with stirring and the reaction was carried out at this temperature for 10 hours. Product (polyester)
Was a viscous liquid and had an acid value of 28 mgKOH / g. Next, the above product was cooled to 70 ° C., 1 part of triphenylphosphine (catalyst) was added and dissolved, and 182 parts of alicyclic epoxy acrylate (manufactured by Daicel Chemical Industries, Cyclomer A200) was stirred for 2 hours. Was added dropwise, and the reaction was continued until the acid value reached 1 mgKOH / g. Hereinafter, this product is referred to as "intermediate 7".

(Example 1: Synthesis of "dispersant 1") A glass flask having a capacity of 2 liters equipped with a stirrer, a Dimroth condenser, a thermometer, and a nitrogen gas introducing tube was charged with 950 parts of "intermediate 1". The internal temperature was raised to 60 ° C. While stirring the contents of the flask, under a nitrogen gas stream, polyethyleneimine (Nippon Shokubai Co., SP200, molecular weight: 1
50,000) 50 parts were charged and reacted at a temperature of 60 ° C. A sample taken during the reaction was confirmed by proton NMR to disappear from the sample, and the reaction was terminated. The reaction product has an amine value of 52 mgKOH
/ G waxy appearance, the hue when melting is APHA 1
20. Hereinafter, this product is referred to as "dispersant 1".

Example 2 Synthesis of "Dispersant 2" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 2" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP200, molecular weight: 10,000) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. Proton NM for samples collected during the reaction
It was confirmed by R that the acrylic group had disappeared from the sample, and the reaction was terminated. The reaction product has an amine value of 55 m.
It has a waxy form of gKOH / g and its hue when melted is AP
It was 120 in HA. Hereinafter, this product is referred to as "dispersant 2".

Example 3: Synthesis of "Dispersant 3" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 3" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP200, molecular weight: 10,000) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. Proton NM for samples collected during the reaction
It was confirmed by R that the acrylic group had disappeared from the sample, and the reaction was terminated. The reaction product has an amine value of 54 m.
It has a waxy form of gKOH / g and its hue when melted is AP
It was 130 in HA. Hereinafter, this product is referred to as "dispersant 3".

Example 4: Synthesis of "Dispersant 4" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 4" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP200, molecular weight: 10,000) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. Proton NM for samples collected during the reaction
It was confirmed by R that the acrylic group had disappeared from the sample, and the reaction was terminated. The reaction product has an amine value of 52 m.
It has a waxy form of gKOH / g and its hue when melted is AP
It was 150 in HA. Hereinafter, this product is referred to as "dispersant 4".

Example 5: Synthesis of "Dispersant 5" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 5" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP200, molecular weight: 10,000) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. Proton NM for samples collected during the reaction
It was confirmed by R that the acrylic group had disappeared from the sample, and the reaction was terminated. The reaction product has an amine value of 55 m.
It has a waxy form of gKOH / g and its hue when melted is AP
It was 190 in HA. Hereinafter, this product is referred to as "dispersant 5".

Example 6: Synthesis of "Dispersant 6" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 6" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP018, molecular weight: 1800) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. A sample taken during the reaction was confirmed by proton NMR to disappear from the sample, and the reaction was terminated. The reaction product has an amine value of 52 mgKO
It exhibited a waxy form of H / g, and the hue when melted was 200 with APHA. Hereinafter this product is referred to as "dispersant 6".

(Example 7: Synthesis of "dispersant 7") In the same glass flask used for the synthesis of "dispersant 1",
950 parts of "Intermediate 7" were charged and the internal temperature was raised to 60 ° C. While stirring the contents of the flask, 50 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP018, molecular weight: 1800) was charged under a nitrogen gas stream and reacted at a temperature of 60 ° C. A sample taken during the reaction was confirmed by proton NMR to disappear from the sample, and the reaction was terminated. The reaction product has an amine value of 55 mgKO
It exhibited a waxy form of H / g, and the hue when melted was 200 with APHA. Hereinafter this product is referred to as "dispersant 7".

Example 8: Synthesis of "Dispersant 8" In the same glass flask used for the synthesis of "Dispersant 1",
950 parts of "Intermediate 2" were charged and the internal temperature was raised to 60 ° C. 100 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP018, molecular weight: 1800) was charged under a nitrogen gas stream while stirring the contents of the flask and reacted at a temperature of 60 ° C. Proton NMR for samples collected during the reaction
Thus, it was confirmed that the methacrylic group had disappeared from the sample, and the reaction was terminated. The reaction product has an amine value of 50 m.
It has a waxy form of gKOH / g and its hue when melted is AP
It was 150 in HA. Hereinafter this product is referred to as "dispersant 8".

(Example 9: Synthesis of "dispersant 9") In the same glass flask used for the synthesis of "dispersant 1",
950 parts of "Intermediate 5" were charged and the internal temperature was raised to 60 ° C. 100 parts of polyethyleneimine (manufactured by Nippon Shokubai Co., SP018, molecular weight: 1800) was charged under a nitrogen gas stream while stirring the contents of the flask and reacted at a temperature of 60 ° C. Proton NMR for samples collected during the reaction
Confirm that the acrylic group has disappeared from the sample,
The reaction was completed. The reaction product has an amine value of 49 mgK
It has a OH / g wax shape and the hue when melted is APHA.
Was 120. Hereinafter this product is referred to as "dispersant 9".

Comparative Example 1: Synthesis of "Dispersant 10" In the same glass flask used for the synthesis of "Dispersant 1",
116 parts of caproic acid, 2,000 parts of caprolactone, and 2 parts of tetrabutyl titanate were charged. The internal temperature was raised to 185 ° C., and the reaction was carried out at this temperature for 18 hours. The acid value of the obtained intermediate (polycaprolactone) is 26 mg.
KOH / g. The same glass flask used for the synthesis of the above intermediate was charged with 1,000 parts of the above intermediate, and the internal temperature was raised to 150 ° C. Polyethyleneimine (Nippon Shokubai Co., SP200, molecular weight: 10,000) 100 under a nitrogen gas stream while stirring the contents of the flask.
And 600 ml of toluene (dehydrated solvent) were charged and reacted at a temperature of 150 ° C. The reaction was stopped when the amount of dehydrated water reached 14 ml. After a part of the product containing toluene was collected and the solvent was removed, the amine value was measured and found to be 70 mgKOH / g, and the hue when melted was 500 as APHA. Also, from the IR spectrum, absorption of an amide group was observed at 1650 and 1550 cm ^-1, and it was confirmed that the polyester chain was grafted to polyethyleneimine via an amide bond.

(Application Examples and Application Comparative Examples) The following examples are
It shows a test in which a pigment is actually dispersed using the dispersant obtained in the above Examples and Comparative Examples, and a coating test in which a substrate is applied as a paint and baked to measure the surface gloss. In the following examples, the fluidity of the pigment dispersion paste and the gloss of the coating film surface are measured by the following methods. (1) Fluidity of the pigment-dispersed paste: visual evaluation, (2) Gloss of coating film surface: measurement by gloss meter

(Application Example 1) Titanium oxide (manufactured by Ishihara Sangyo Co., Ltd., Taipaque CR95: C-I-PigmentWh)
ite 6) 75 parts, "dispersant 1" 1 part, xylene 7
Parts, butyl cellosolve acetate 7 parts, glass beads 1
00 parts were weighed and treated with a disperser (manufactured by Red Devil Co.) for 60 minutes to disperse them. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 2) Carbon black (Mitsubishi Chemical Corporation, MA-100: CI Pigment Bl)
ack 7) 20 parts, "dispersant 1" 4 parts, xylene 38
Parts, 38 parts of butyl cellosolve acetate, and 100 parts of glass beads are weighed, and then weighed with a disperser (same as above)
It was treated for 0 minutes and dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 3) Phthalocyanine blue (manufactured by Dainichiseika Kogyo Co., Ltd., Chromofine Blue 4920:
C. I-Pigment Blue 15: 3) 25 parts,
10 parts of "dispersing agent 1", 32.5 parts of xylene, 32.5 parts of butyl cellosolve acetate, and 100 parts of glass beads were weighed and treated with a disperser (the same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 4) 75 parts of titanium oxide (the same kind as used in Application Example 1), 1 part of "dispersant 2",
7 parts of xylene, 7 parts of butyl cellosolve acetate, and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 5) Carbon black (the same kind as used in Application Example 2) 20 parts, "Dispersant 2"
4 parts, xylene 23 parts, butyl cellosolve acetate 2
3 parts and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 6) 25 parts of phthalocyanine blue (the same kind as used in application example 2), 10 parts of "dispersant 2", 32.5 parts of xylene, 32.5 parts of butyl cellosolve acetate, 100 glass beads. Each part was weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 7) 75 parts of titanium oxide (the same kind as used in Application Example 1), 1 part of "dispersant 3",
7 parts of xylene, 7 parts of butyl cellosolve acetate, and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 8) Carbon black (the same kind as used in Application Example 2) 20 parts, "dispersant 3"
4 parts, xylene 23 parts, butyl cellosolve acetate 2
3 parts and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 9) 25 parts of phthalocyanine blue (the same kind as used in application example 2), "Dispersant 3" 10 parts, xylene 32.5 parts, butyl cellosolve acetate 32.5 parts, glass beads 100 Each part was weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 10) Phthalocyanine green (manufactured by Dainichiseika Kogyo Co., Ltd., Chromophine Green 531)
0: C.I. 25 parts of I-Pigment Green7),
"Dispersant 7" 10 parts, xylene 65 parts, glass beads 1
00 parts were each weighed and then 60 with a disperser (same as above)
It was treated for minutes and dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 11) Benzimidazolone Yellow (Chromophine Yellow 2 manufactured by Dainichi Seika Kogyo Co., Ltd.)
080: C.I. I-Pigment Yellow15
4) 45 parts, 5 parts of "dispersant 8", 50 parts of xylene, and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 12) Yellow iron oxide (manufactured by Titanium Industry Co., Ltd., Mapicoello LLXLO: C.I-Pigme)
nt Yellow 42) 60 parts, "Dispersant 9" 2 parts,
38 parts of xylene and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 13) Bengara (CIP)
igment Red 101) 70 parts, "Dispersant 8"
2 parts, xylene 14 parts, butyl cellosolve acetate 1
4 parts and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 14) Quinacridone (manufactured by Dainichiseika Kogyo Co., Ltd., Chromofine Red 6820: CI-
Pigment Violet 19) 40 parts, "Dispersant 2" 2 parts, methyl isobutyl ketone 29 parts, butyl cellosolve acetate 29 parts, glass beads 100 parts, respectively, weighed, treated with a disperser (the same as above) for 60 minutes,
Dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 15) Brilliant Carmine 6B (manufactured by Dainippon Ink and Chemicals, Inc., Shimla Brilliant Carmine 6B 236: C. I-Pigment R)
ed 57: 1) 45 parts, "dispersant 2" 2.5 parts, xylene 52.75 parts, and glass beads 100 parts were weighed and treated with a disperser (same as above) for 60 minutes to disperse. . The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 16) Disazo Yellow (manufactured by Dainichiseika Kogyo KK, Seika Fast Yellow 2300:
C. I-Pigment Yellow 12) 40 parts,
"Dispersant 4" 2 parts, xylene 5 parts, glass beads 100
Each part was weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste shows good fluidity, and even after standing at room temperature for 1 week,
It showed good fluidity.

(Application Example 17) Carbon black (manufactured by Degussa Co., FW-200: CI Pigment B)
20 parts of rack 7), 10 parts of "dispersant 5", 70 parts of xylene, and 100 parts of glass beads were weighed and treated with a disperser (the same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste shows good fluidity, and
Even after being left at room temperature for 1 week, it showed good fluidity.

(Application Example 18) 20 parts of carbon black (the same as that used in Application Example 17), 10 parts of "dispersant 6", 70 parts of xylene, and 100 parts of glass beads were weighed and dispersed. (Same as above) for 60 minutes and dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 19) 20 parts of carbon black (the same kind as used in Application Example 17), 10 parts of "dispersant 9", 70 parts of xylene, and 100 parts of glass beads were respectively weighed and dispersed. (Same as above) for 60 minutes and dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 20) Diketopyrrolopyrrole (manufactured by Ciba-Geigy, DPP Red BO: C.I-
Pigment Red 254) 45 parts, "Dispersant 3" 3 parts, xylene 52 parts, glass beads 100 parts,
Each was weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

(Application Example 21) 20 parts of carbon black (the same as that used in Application Example 17), 10 parts of "dispersant 7", 70 parts of xylene, and 100 parts of glass beads were weighed and dispersed by a disperser ( (Same as above) for 60 minutes and dispersed. The obtained pigment-dispersed paste showed good fluidity, and even after left at room temperature for 1 week, it showed good fluidity.

Application Comparative Example 1 20 parts of carbon black (the same kind as used in Application Example 17), "Dispersant 1"
10 parts of 0 ", 70 parts of xylene, and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained pigment-dispersed paste showed fluidity immediately after the dispersion paste was prepared.
After leaving for a week, it became a jelly and did not show fluidity.

Application Comparative Example 2 20 parts of carbon black (the same kind as used in Application Example 17), alkyd resin (manufactured by Dainippon Ink and Chemicals, Inc., Beccosol EZ-)
3530-80, solvent: xylene, nonvolatile content 80%) 1
2.5 parts, 67.5 parts of xylene, and 100 parts of glass beads were weighed and treated with a disperser (same as above) for 60 minutes to disperse. The obtained dispersion paste was gel-like and showed no fluidity.

(Application Examples 22 to 23, Application Comparative Example 3)
A coating composition having the compounding ratios shown in Table 1 below was prepared for each of the three pigment dispersion pastes of Application Example 3, Application Example 19 and Application Comparative Example 1 described above.

[0103]

[Table 1]

The coating composition thus obtained was applied to the surface of a substrate (mirror-finished metal plate) and baked at a temperature of 135 ° C. for 30 minutes to form a coating film on the substrate. Immediately after forming this coating film and after standing at a low temperature of 0 ° C. for 3 days, the gloss of the coating film surface was measured. The measurement results are shown in Table 2 below.

[0105]

[Table 2]

From the examples and applied examples, the following is clear. (1) The pigment dispersant according to the present invention has excellent pigment dispersibility,
Demonstrate storage stability (Application Example 1-Application Example 2)
1). In contrast, the dispersants containing no pigment dispersant according to the present invention (Application Comparative Example 1 and Application Comparative Example 3) do not exhibit excellent pigment dispersibility. (2) Among the pigment dispersants according to the present invention, the pigment dispersant derived from a polyester / polycarbonate copolymer containing a lactone having a side chain does not reduce the gloss of the coating film even when left at a low temperature. This indicates that precipitation of the pigment dispersant due to crystallization of the polycarbonate portion does not occur even at low temperatures.

[0107]

INDUSTRIAL APPLICABILITY The present invention has the following special advantageous effects and its industrial utility value is extremely large. 1. The pigment dispersant according to the first aspect of the present invention has a highly compatible vehicle and / or polyester / polycarbonate component in the molecular chain, and unlike the conventional dispersants, the dispersant crystallizes. The problem does not occur. 2. The pigment dispersant according to the first aspect of the present invention has a polyamine-derived adsorption group that is easily adsorbed to the pigment, inhibits the solubility in a solvent that is present in conventional dispersants, and does not contribute to adsorption to the pigment. Does not contain amide groups. Therefore, it has good compatibility with many dispersible resins and exhibits extremely good dispersibility with respect to a wide range of pigments. 3. Since the pigment dispersant according to the first aspect of the present invention is less colored during the production thereof, it does not impair the original hue of the pigment, and an excellent quality product can be obtained during the preparation of the pigment composition. .

Embedded image

Embedded image

Embedded image

Embedded image

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Nakano 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Japan Paint Co., Ltd. (72) Shinya Yamada 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Japan Paint Within the corporation

Claims (9)

[Claims] 1. A general formula containing a unit formed by ring opening of a cyclic carbonate compound represented by the general formula (1) as a structural component and having a functional group capable of undergoing a Michael addition reaction with an amino group at one end. A pigment dispersant obtained by subjecting a polycarbonate compound represented by (2) to a Michael addition reaction of a polyamine compound. Embedded image Embedded image 2. A polycarbonate polymer represented by the general formula (2) is a copolymer chain of a lactone compound represented by the general formula (3) and a cyclic carbonate compound represented by the general formula (1). The pigment dispersant according to claim 1, which is a copolymer having Embedded image 3. An amine value of 10 to 500 mg KOH /
The pigment dispersant according to claim 1, which is in the range of g. 4. The average molecular weight of the copolymer chain containing a lactone compound unit contained in the pigment dispersant is 100.
The pigment dispersant according to claim 2, which is about 10,000. 5. A polyamine compound having a molecular weight of 100 to 1
The pigment dispersant according to claim 1, which is 0,000. 6. The pigment dispersant according to claim 1, wherein the polyamine compound is selected from polyethyleneimine, polyallylamine, and polyvinylamine. 7. The pigment dispersant according to claim 1, wherein the polycarbonate compound represented by the general formula (2) is represented by the following general formula (4). Embedded image 8. A general formula containing a unit formed by ring opening of a cyclic carbonate compound represented by the general formula (1) as a structural component and having a functional group capable of undergoing a Michael addition reaction with an amino group at one end. A method for producing a pigment dispersant, which comprises preparing a polycarbonate compound represented by (2), and then subjecting the polycarbonate polymer and a polyamine compound to a Michael addition reaction. Embedded image [Chemical 6] 9. A printing ink composition containing the pigment dispersant according to claim 1.