JP2013053200A - Pigment aqueous dispersion composition, and aqueous ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pigment aqueous dispersion composition which has no odor, is excellent in safety in the working environment and in handling in use as an ink and a coating, is inexpensive in production cost because of no need for special facilities in production such as an explosionproof facility, an exhaust facility and an organic solvent recovery apparatus, which would be needed in the case of organic solvent-type coloring materials, and exhibits excellent dispersibility; and to provide an aqueous ink composition which provides a coated film exhibiting excellent image density and concealability and excellent gloss.SOLUTION: The pigment aqueous dispersion composition contains an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C). The aqueous ink composition contains the pigment aqueous dispersion composition.

Description

  The present invention relates to an aqueous pigment dispersion composition and an aqueous ink composition.

In recent years, water-based inks have been widely used to replace organic solvent-based inks in a wide range of fields because of their safety and low environmental impact. Especially for business use, water-based color materials that do not smell are essential as inks used for various printing in offices, and for industrial use, organic solvents are used due to problems in the working environment, safety of ink and paint handling, and waste liquid treatment. There is an increasing tendency to use as little as possible. In addition, water-based colorants are also more popular than organic solvent-type colorants because they do not require special equipment such as explosion-proof equipment, exhaust equipment, and organic solvent recovery equipment during production. .

  As the water-based coloring material, two dyes and pigments are mainly used depending on the application. The dye has excellent gradation and easily forms a high-resolution image, but has low light resistance and has a practical problem. On the other hand, since pigments are extremely excellent in water resistance and light resistance, many pigment inks are now provided.

  Gravure inks that are printed via printing plate making and water-based liquid inks for offset printing have been developed, but the most popular recording method for offices that uses water-based inks is the ink jet recording method.

  The ink jet recording method is a method in which ink droplets are ejected from a fine nozzle head and characters and images are recorded on the surface of a recording medium such as paper. Since it can be easily printed on demand without making a full color printing plate on a simple recording medium, it has begun to spread widely.

  An ink jet printer that employs an ink jet recording method is a method in which ink droplets are ejected from a fine nozzle head and characters and images are recorded on the surface of a recording medium such as paper. (Registered trademark) method and piezo method. The former is a recording method that instantaneously heats the ink guided to the nozzle head with a heater to generate bubbles, and the ink expansion is intermittently ejected by volume expansion due to the bubbles, the latter is an electrostrictive element (piezoelectric element) Is a recording method in which an electrical signal is converted into a mechanical signal using ink and ink droplets stored in a nozzle head portion are ejected intermittently.

  On the other hand, as described above, although the pigment is excellent in light resistance as compared with the dye, it has a low affinity with other substances such as organic polymers, water, and organic solvents compared with the cohesion between the pigment particles. Dispersibility is low, and it is extremely difficult to uniformly mix or disperse under normal mixing or dispersion conditions.

  For this reason, for example, as a method for improving the dispersibility of the black pigment, Patent Document 1 (Japanese Patent Application Laid-Open No. Hei 8-218015) adsorbs a dispersant composed of various surfactants on the entire surface of the black pigment. Ink jet ink compositions having improved affinity with other components have been proposed.

  Furthermore, in order to improve performance such as scratch resistance and marker resistance of the resulting coating film, an ink-jet ink composition containing an aqueous resin such as a resin emulsion has been studied.

Japanese Patent Laid-Open No. 8-21815

  However, when the blending ratio of the resin in the inkjet ink composition is higher than the blending ratio of the pigment, the gloss of the resulting coating film is improved, but the image density (color density) and the concealing property of the coating film are reduced. When the blending ratio of the pigment in the ink-jet ink composition is higher than the blending ratio of the resin, the image density and concealment of the resulting coating film are improved, but the gloss is lowered, and the scratch resistance and marker resistance are also decreased. Resulting in. The characteristics such as image density (color density), coating concealability, and gloss are particularly important in ink-jet ink compositions using organic pigments for color printing. Marker properties are also important.

  The present invention has been made in order to improve such a contradictory relationship, and provides an aqueous pigment dispersion composition exhibiting excellent dispersibility, and the obtained coating film has excellent image density and hiding. It is an object of the present invention to provide a water-based ink composition that exhibits properties and excellent gloss.

  In order to achieve the above object, the present inventors have intensively studied, and include an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C). It has been found that the above technical problem can be solved by the pigment aqueous dispersion composition to be completed, and the present invention has been completed based on this finding.

That is, the present invention
(1) A pigment aqueous dispersion composition comprising an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B) and a dispersant (C),
(2) The aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule is represented by the following general formula (I)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, which may be the same or different, and R ¹ And R ² may combine to form a cyclic structure, wherein R ³ is an alkylene group having 1 to 22 carbon atoms, and R ⁴ is an alkylene group having 0 to 22 carbon atoms. The aqueous pigment dispersion composition as described in (1) above, wherein the diol compound (a1) having an imide group in the side chain is subjected to urethane reaction as a monomer raw material,
(3) The aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule is further represented by the following general formula (II)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, which may be the same or different, and R ¹ And R ² may be bonded to form a cyclic structure, and R ³ is an alkylene group having 1 to 22 carbon atoms.) The aqueous pigment dispersion composition according to the above (2), which is obtained by subjecting a side chain or a terminal of a chain to urethane reaction,
(4) The pigment dispersion composition according to any one of (1) to (3), wherein the pigment (B) is a phthalocyanine pigment,
(5) While containing 3 to 35% by mass of the pigment (B),
In terms of solid content, 2 to 200 parts by mass of the aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule and 1 to 30 parts by mass of the dispersant (C) with respect to 100 parts by mass of the pigment (B). The aqueous pigment dispersion composition according to any one of (1) to (4) above,
(6) A water-based ink composition comprising the pigment aqueous dispersion composition according to any one of (1) to (5) above,
Is to provide.

  According to the present invention, an aqueous pigment dispersion that exhibits excellent dispersibility by including an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C). An object of the present invention is to provide a dispersion composition, and to provide a water-based ink composition in which the obtained coating film exhibits excellent image density and hiding properties and exhibits excellent gloss.

  The aqueous pigment dispersion composition of the present invention comprises an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C).

  In the aqueous pigment dispersion composition of the present invention, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is preferably one having a cyclic imide group at the side chain or terminal of the molecular chain. Examples of the resin include those obtained by subjecting a diol compound having a cyclic imide group represented by the following general formula (I) in the side chain to a urethane reaction as a monomer raw material, and a cyclic imide group represented by the following general formula (I) having a side chain. The diol compound (a1) contained in the product is subjected to urethane reaction as a monomer raw material, and the cyclic imide monool compound (a2) represented by the general formula (II) described later is further used as a monomer raw material at the side chain or terminal of the polyurethane main chain. The thing made by urethane reaction is mentioned.

In the aqueous pigment dispersion composition of the present invention, as the aqueous polyurethane resin (A) having a cyclic imide group in the molecule, the following general formula (I)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having a carbon number, and may be the same or different, and R ¹ and R ² may be the same. R ³ is an alkylene group having 1 to 22 carbon atoms, and R ⁴ is an alkylene group having 0 to 22 carbon atoms. Those obtained by subjecting a diol compound (a1) having a side chain to a urethane reaction as a monomer raw material are preferred.

In the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain, R ¹ and R ² are a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms. And each may be the same or different, and R ¹ and R ² may be bonded to form a cyclic structure.
R ¹ and R ² have 1 to 6 carbon atoms, and R ¹ and R ² may have the same or different carbon numbers.

Examples of the substituent that R ¹ and R ² can adopt include a linear or branched aliphatic hydrocarbon group, and an alicyclic hydrocarbon group in which R ¹ and R ² are bonded to form a cyclic structure. And an aromatic hydrocarbon group in which R ¹ and R ² are bonded to form a cyclic structure.
When R ¹ and R ² are linear or branched aliphatic hydrocarbon groups, specifically, alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group Can be mentioned.
When R ¹ and R ² are an alicyclic hydrocarbon group in which both are bonded to form a cyclic structure, specifically, a 3, 4, 5, 6-tetrahydrophthalimide group together with an adjacent cyclic imide group Are formed.
In addition, when R ¹ and R ² are aromatic hydrocarbon groups in which both are bonded to form a cyclic structure, specifically, those formed by constituting a phthalimide group together with an adjacent cyclic imide group can be mentioned. .

In the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain, R ¹ and R ² are an alicyclic hydrocarbon group in which both are bonded to form a cyclic structure, or both Is preferably an aromatic hydrocarbon group having a cyclic structure.

When the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain is subjected to urethane reaction with a polyisocyanate compound as a monomer raw material, a polyurethane resin having a cyclic imide group in the side chain is formed.
In the polyurethane resin, the cyclic imide group has high polarity, but the hydrocarbon groups such as aliphatic hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups composed of R ¹ and R ² have low polarity. Therefore, it is considered that a polarity difference is generated in the polyurethane resin, and this polarity difference contributes to the dispersibility of the pigment (B).
In addition, the aqueous pigment dispersion composition of the present invention is converted into an inkjet ink composition or a coating material by a hydrocarbon group such as an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group composed of R ¹ and R ^2. When used in a composition, the resulting coating is believed to exhibit excellent gloss.

In the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain, R ³ has 1 to 22 carbon atoms, preferably 1 to 18 carbon atoms, more preferably 1 to 12 carbon atoms. R ⁴ is an alkylene group having 0 to 22 carbon atoms, preferably 0 to 18 carbon atoms, and more preferably 0 to 12 carbon atoms.

Specific examples of the alkylene group represented by R ³ include methylene, ethylene, trimethylene [propane-1,3-diyl], tetramethylene [butane-1,4-diyl], pentamethylene [pentane-1,5- diyl], hexamethylene [hexane-1,6-diyl], heptamethylene [heptane-1,7-diyl] octamethylene [octane-1,8-diyl], nonamethylene [nonane-1,9-diyl], dodeca Mention may be made of methylene [dodecane-1,12-diyl], octadecane-1,18-diyl, docosamethylene [docosane-1,22-diyl] and the like.

Specific examples of the alkylene group represented by R ⁴ include methylene, ethylene, trimethylene [propane-1,3-diyl], tetramethylene [butane-1,4-diyl], pentamethylene [pentane-1, 5-diyl], hexamethylene [hexane-1,6-diyl], heptamethylene [heptane-1,7-diyl], octamethylene [octane-1,8-diyl], nonamethylene [nonane-1,9-diyl] And dodecane-methylene [dodecane-1,12-diyl].

  The diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain can be preferably used as a compound constituting the main chain of the polymer chain in the aqueous polyurethane resin (A).

Examples of the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain include compounds introduced from hexahydrophthalic anhydride and amine diol in which R ¹ and R ² form a ring. Specifically, a compound represented by the following formula (I ′) (1- (hexahydrophthalimide) -2,3 hydroxypropane) can be mentioned.

  When the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain is a compound represented by the above formula (I ′), the hexahydrophenyl structure is a low polarity lipophilic structure. Since the imide group has a structure with high polarity, it is considered that the structure with low polarity and the structure with high polarity contribute to the dispersibility of the pigment (B), and the aqueous dispersion of the pigment of the present invention has a hexahydrophenyl structure. When the body composition is used in an inkjet ink composition or a coating composition, it is considered that the resulting coating film exhibits excellent gloss.

  The diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain is prepared by reacting an acid anhydride with an aminodiol having two primary amino groups and two hydroxyl groups in the molecule. be able to.

  Examples of the acid anhydride include aromatic acid anhydrides such as phthalic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, and 4-methylhexahydro. Fats such as phthalic anhydride, hexahydrophthalic anhydride, methylbicyclo [2.2.1] heptane-2,3-dicarboxylic anhydride, bicyclo [2.2.1] heptane-2,3-dicarboxylic anhydride Examples thereof include aliphatic anhydrides such as cyclic anhydrides, 3-octenyl succinic anhydride, and 3-dodecenyl succinic anhydride.

  Examples of the aminodiol having two primary amino groups and two hydroxyl groups in the molecule include 1-aminopropanediol.

  The acid anhydride is ring-opened by the above reaction and reacts with the primary amino group of aminodiol to produce an amic acid having an amide group and a carboxyl group, and the resulting cyclic acid is dehydrated and cyclized to form a target cyclic imide group Can be obtained in the side chain. The amic acid production reaction is an exothermic reaction, and it is desirable to carry out the reaction while controlling the reaction temperature to 90 ° C. or less by dividing and gradually adding an acid anhydride using an organic solvent such as toluene. After adding an acid anhydride equivalent to the primary amino group of aminodiol, the temperature is gradually raised, and when the organic solvent is toluene, dehydration is performed while removing condensed water near its boiling point (around 110 ° C.). It is preferable to carry out a ring-closing reaction.

  The dehydration ring closure reaction can be carried out without a catalyst, or it can be carried out using any known catalyst for zirconium-based, titanium-based, tin, or aluminum-based polyesters that promotes dehydration condensation using tetraisopropoxy titanium or the like. It is preferable to carry out.

  In the dehydration cyclization reaction, it is preferable to promote the dehydration reaction by maintaining the reflux temperature while blowing nitrogen gas. Since the carboxyl group of the amic acid decreases when the ring is closed, the reaction rate can be determined by measuring the acid value. When all amic acids are ring-closed to form imide groups, the acid value is 0 mgKOH / g.

  For example, the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain is 1- (hexahydrophthalimide) -2,3 hydroxypropane represented by the above general formula (I ′). In some cases, it is produced by reacting hexahydrophthalic anhydride with 1-aminopropanediol (reacting an acid anhydride with a primary amine) to form an amic acid, and dehydrating and ring-closing the resulting amic acid. can do.

  The aqueous pigment dispersion composition of the present invention has a dispersibility because the cyclic imide group constituting the aqueous polyurethane resin (A) having a cyclic imide group in the molecule itself has a low-polarity structure part and a high-polarity structure part. In addition, when used in an ink composition or a coating composition, it can improve the adhesion to printed matter and coating material, and the wettability to pigments. When the aqueous polyurethane resin (A) having a group has a structural unit derived from the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain, the above effect can be easily obtained. It can be demonstrated.

  In the aqueous pigment dispersion composition of the present invention, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule together with the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain Furthermore, it is preferable that a polyol compound (a3) having a polar molecular chain and a polyol compound (a4) having a low polar molecular chain are subjected to a urethane reaction using a monomer raw material.

  Examples of the polyol compound (a3) having a polar molecular chain include a polyol compound having at least a functional group or molecular chain dispersible in an aqueous medium and having two or more hydroxyl groups, and having two hydroxyl groups. A diol compound is preferred.

  As a diol compound having at least a functional group or molecular chain dispersible in an aqueous medium and having two hydroxyl groups, a diol compound having a functional group capable of forming a salt that causes phase inversion of the polyurethane resin in the aqueous medium Specific examples include tertiary carboxyl group-containing diol compounds.

Examples of the tertiary carboxyl group-containing diol compound include a tertiary carboxyl group-containing diol compound.
Examples thereof include dihydroxycarboxylic acids such as dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolacetic acid, dimethylolbutyric acid, dimethylolvaleric acid, and dimethylolcaproic acid. Among these, dimethylolpropionic acid, dimethylolbutane Dihydroxy monocarboxylic acids such as acids are preferred.
Since the tertiary carboxyl group of the above compound has extremely low reactivity with a polyisocyanate compound or the like, the target polyurethane resin can be efficiently produced without inhibiting the urethane bond reaction.

  Moreover, as a polyol compound (a3) which has a polar molecular chain, the diol compound which has a nonionic molecular chain can be mentioned. Examples of the diol compound having a nonionic molecular chain include polyethylene glycol diol (PEG), polyglycol represented by polyethylene glycol diol (PEG), polypropylene glycol diol (PPG), and polybutylene glycol diol (PBG) copolymerized diol. Mention may be made of alkylene glycol diols.

  By controlling the blending amount of the tertiary carboxyl group-containing diol compound, the acid value of the resulting polyurethane resin can be controlled. In order to adjust the acid value, in addition to the tertiary carboxyl group-containing diol compound, Furthermore, a diol compound having a nonionic molecular chain can be appropriately used.

  Examples of the polyol compound (a4) having a low polar molecular chain include ethylene glycol, propylene glycol, cyclohexane-1,4-dimethanol, 1,3-butylene glycol, 1,4-butylene glycol, neopentyl glycol, 1,6 -Hexanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8-octane Diols such as diol, 1,9-nonanediol, and cyclohexyldimethanol can be exemplified, and further, a polymer polyol having a low polar molecular chain can be exemplified.

Examples of the polymer polyol include polymer diols such as polyester polyol, polycarbonate diol, polylactone diol, polyether polyol, and butadiene diol, and polymer diols of compounds having a rosin skeleton or a hydrogenated rosin skeleton.
The polymer polyol preferably has a number average molecular weight in the range of 300 to 5,000, more preferably 500 to 3,000 in number average molecular weight.

  Examples of the polyester polyol include those obtained by condensation reaction of one or more of the following polyols and polyol synergistic components with one or more of polybasic acids and anhydrides thereof.

  Polyester polyol raw material polyols include ethylene glycol, propylene glycol, cyclohexane-1,4-dimethanol, 1,3-butylene glycol, 1,4-butylene glycol, neopentyl glycol, 1,6-hexanediol, 3- Methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8-octanediol, 1,9- Nonanediol, cyclohexanedimethanol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, castor oil-modified diol, castor oil-modified polyol, and the like can be given.

  Polyol synergistic components that are raw materials for polyester polyols include alkyl monoglycidyl ethers such as butyl glycidyl ether, 2-ethylhexyl glycidyl ether, lauryl glycidyl ether, decyl glycidyl ether and stearyl glycidyl ether, and alkyl glycidyl esters (for example, One or more of monoepoxy compounds such as Shell Japan's Cardura E10) can be mentioned.

  Polybasic acids and their anhydrides that are raw materials for polyester polyols include aliphatic dibasic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid and dimer acid, and their anhydrides, dodecenyl succinic anhydride, Aromatic polybasic acids such as phthalic anhydride, isophthalic acid, terephthalic acid and trimellitic anhydride, and anhydrides thereof, alicyclic polybasic acids such as hydrophthalic anhydride and dimethyl-1,4-cyclohexanedicarboxylic acid, and the like The anhydride of these is mentioned.

  Examples of the polycarbonate diol include 1,4 butanediol, 1,6 hexanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, and 2-butyl-2-ethyl-1,3. -Polycarbonate diols using diols such as propanediol, 1,9-nonanediol and 2-methyl-1,8-octanediol as raw materials.

  The polylactone diol is obtained by ring-opening addition polymerization of a monomer having a lactone ring such as ε-caprolactone or β-methyl-δ-valerolactone, starting from a hydroxyl-terminated compound such as the above-mentioned polyol or polyester polyol. Examples include lactone diols.

  Examples of the polyether polyol include polyalkylene glycols represented by polyethylene glycol diol (PEG), polypropylene glycol diol (PPG), polybutylene glycol diol (PBG), bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated Examples thereof include polyether polyols to which propylene oxide, tetrahydrofuran, butylene oxide is added using bisphenol F or the like as a starting material.

  As polybutadiene diol, the following formula:

(However, k = 0.2, l = 0.2, m = 0.6, and n is a positive integer.) Polybutadienediol Poly bdR-15HT, R-45HT represented by Idemitsu Kosan Co., Ltd. ), Polyisoprene diol Poly ip (made by Idemitsu Kosan Co., Ltd.), and the following formula

(In the formula, n represents a positive integer.)
Α, ω-polybutadiene glycol G-1000, G-2000, G-3000 (manufactured by Nippon Soda Co., Ltd.) and the like represented by

  Examples of the polymer diol of the compound having a rosin skeleton or a hydrogenated rosin skeleton include Pine Crystal D-6011 and D-6240 (manufactured by Arakawa Chemical Industries).

  In the pigment dispersion composition of the present invention, the water-based polyurethane resin (A) having a cyclic imide group in the molecule, together with a diol compound having a cyclic imide group represented by the above general formula (I) in the side chain, Formula (II)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, which may be the same or different, and R ¹ And R ² may be bonded to form a cyclic structure, and R ³ is an alkylene group having 1 to 22 carbon atoms.) It is preferable that the side chain or terminal of the chain is urethane-reacted.

As the ^{R 1,} R 2, ^{R 3,} respectively, similar to ^{R 1,} R 2, ^{R 3} constituting the diol compound (a1) having a cyclic imide group represented by the above-mentioned general formula (I) in a side chain Can be mentioned.
In the pigment dispersion composition of the present invention, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is derived from a diol compound having a cyclic imide group represented by the above general formula (I) in the side chain. When it has a structural unit derived from the cyclic imide monool compound (a2) represented by the general formula (II) together with the structural unit, it constitutes the cyclic imide monool compound (a2) represented by the general formula (II). R ¹ , R ² and R ³ were the same as R ¹ , R ² and R ³ constituting the diol compound (a1) having the cyclic imide group represented by the above general formula (I) in the side chain, respectively. It may be different or different.

  The cyclic imide monool compound (a2) represented by the general formula (II) is a primary compound in the molecule in the production method of the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain. It can be prepared by reacting in the same manner except that an amino alcohol having a primary amino group and one hydroxyl group in the molecule is used instead of an amino diol having two amino groups and two hydroxyl groups.

  Examples of the acid anhydride include those similar to those used for preparing a diol compound having a cyclic imide group represented by the general formula (I) in the side chain.

  Examples of amino alcohols having one primary amino group and one hydroxyl group in the molecule include amino alcohols such as monoethanolamine and 3-aminopropanol.

  The acid anhydride is ring-opened to react with the primary amino group of the amino alcohol to produce an amic acid having an amide group and a carboxyl group, and by dehydrating and ring-closing the produced amic acid, the target cyclic imide group is located on the side. A diol compound having a chain can be obtained. The amic acid production reaction is an exothermic reaction, and it is desirable to carry out the reaction while controlling the reaction temperature to 90 ° C. or less by dividing and gradually adding an acid anhydride using an organic solvent such as toluene. After adding an acid anhydride equivalent to the primary amino group of aminodiol, the temperature is gradually raised, and when the organic solvent is toluene, dehydration is performed while removing condensed water near its boiling point (around 110 ° C.). It is preferable to carry out a ring-closing reaction.

  The dehydration ring closure reaction can be carried out without a catalyst, or it can be carried out using any known catalyst for zirconium-based, titanium-based, tin, or aluminum-based polyesters that promotes dehydration condensation using tetraisopropoxy titanium or the like. It is preferable to carry out.

  In the dehydration cyclization reaction, it is preferable to promote the dehydration reaction by maintaining the reflux temperature while blowing nitrogen gas. Since the carboxyl group of the amic acid decreases when the ring is closed, the reaction rate can be determined by measuring the acid value. When all amic acids are ring-closed to form imide groups, the acid value is 0 mgKOH / g.

  In the pigment dispersion composition of the present invention, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is a polyurethane main chain using the cyclic imide monool compound (a2) represented by the general formula (II) as a monomer raw material. It is preferable that the side chain or terminal of the compound is urethane-reacted, and the cyclic imide monool compound (a2) represented by the above general formula (II) is converted into a polyurethane main component by controlling the order of addition of the monomer raw materials. The urethane can be reacted at the desired position of the chain.

In the pigment dispersion composition of the present invention, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is other than the cyclic imide monool compound (a2) represented by the general formula (II) at the terminal of the polyurethane main chain. The monool compound (a5) may be urethane-reacted.
Examples of the monool compound (a5) include a hydroxyvinyl compound that reacts with a terminal NCO group. Specifically, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, hydroxybutyl (meth) ) Monohydroxy mono (meth) acrylate such as acrylate, N-hydroxyethyl acrylamide, Light ester G-201P (manufactured by Kyoeisha Chemical), Glycerin di (meth) acrylate such as light ester G-101 (manufactured by Kyoeisha Chemical) It is done.

An aqueous polyurethane resin (A) having a cyclic imide group in the molecule is obtained by subjecting a diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain to a urethane reaction as a monomer raw material. In some cases, a polyisocyanate compound is usually used for the urethane reaction.
The polyisocyanate compound is not particularly limited as long as it contains two or more isocyanate groups in the molecule, and a diisocyanate compound or a polyisocyanate compound containing three or more isocyanate groups can be used depending on the purpose.

Examples of the diisocyanate compound include diphenylmethane diisocyanate (hereinafter abbreviated as MDI), polyphenylene polymethylene polyisocyanate, tolylene diisocyanate (hereinafter abbreviated as TDI), xylylene diisocyanate, tetramethylxylylene diisocyanate, and isophorone diisocyanate (hereinafter abbreviated as IPDI). , Hexamethylene diisocyanate (hereinafter abbreviated as HDI), tetramethylene diisocyanate, dodecamethylene diisocyanate, trimethylhexamethylene diisocyanate, 1,3-cyclohexylene diisocyanate, naphthalene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, etc. it can.
Examples of the polyisocyanate compound include those obtained by modifying a part of the isocyanate groups of the above diisocyanate compounds into burette, allophanate, carbodiimide, uretonimine, oxazolidone, amide, imide, isocyanurate, uretdione, and the like.
These polyisocyanate compounds can be used in combination of one or more as required.

An aqueous polyurethane resin (A) having a cyclic imide group in the molecule is produced by urethane reaction of a diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain with a polyisocyanate compound. can do.
In addition, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is a polyol compound (A1) having a cyclic imide group represented by the general formula (I) in the side chain and a polyol compound having a polar molecular chain ( a diol compound (a3) having a polar molecular chain as a3) and a diol compound (a4) having a low polarity molecular chain as a polyol compound (a4) having a low polarity molecular chain as monomer raw materials, a polyisocyanate compound, It can also be produced by a urethane reaction.
Further, the aqueous polyurethane resin (A) having a cyclic imide group in the molecule is obtained by subjecting the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain to a urethane reaction with a polyisocyanate compound. A diol compound (a3) having a polar molecular chain together with a polyurethane resin, a diol compound (a) having a cyclic imide group represented by the general formula (I) in the side chain, and a diol compound (a4) having a low polar molecular chain ) And a polyisocyanate compound as a monomer raw material, and a urethane reaction of the cyclic imide monool compound (a2) represented by the general formula (II) with the isocyanate group at the end of the polyurethane main chain. Can also be produced.
Thus, the active energy ray-curable polyurethane resin of the present invention can be produced by sequentially reacting each compound in various orders.

When the aqueous polyurethane resin (A) having a cyclic imide group in the molecule has an isocyanate group at both ends, for example, an appropriate polar molecular chain is used for the diol compound (a1) having a cyclic imide group in the side chain. Is mixed with the diol compound (a4) having a low-polar molecular chain, and the number of moles of the resulting diol compound is larger than the number of moles of all the diols constituting the mixture. The target active energy ray-curable polyurethane resin can be prepared by adding a diisocyanate compound, which is a polyisocyanate compound, so as to increase the amount of urethane and reacting with urethane.
In the above reaction, when the number of moles of all diols constituting the diol mixture is n, an aqueous polyurethane resin having isocyanate groups at both ends is prepared by adding (n + 1) moles of a diisocyanate compound which is a polyisocyanate compound. be able to.

In the case where the aqueous polyurethane resin (A) having a cyclic imide group in the molecule has hydroxyl groups at both ends, for example, an active energy ray-curable polyurethane resin having isocyanate groups at both ends by the same method as described above. This is used as a polyurethane resin intermediate, and then the terminal isocyanate group of the intermediate is represented by the cyclic imide monool compound (a2) represented by the general formula (II) or the above general formula (II). A monool compound (a5) other than the cyclic imide monool compound (a2) is reacted with the terminal isocyanate group so as to have an equimolar amount, thereby preparing a target aqueous polyurethane resin having hydroxyl groups at both ends. be able to.
In the above reaction, the monool compound (a5) other than the cyclic imide monool compound (a2) represented by the general formula (II) and the cyclic imide monool compound (a2) represented by the general formula (II) Prepared an active energy aqueous polyurethane resin in which 2 moles is equivalent to 2 moles of the intermediate (2 moles of isocyanate groups (NCO groups) in the intermediate), and a monool compound-derived structural unit is introduced at both ends. can do.

  In addition, when preparing the aqueous polyurethane resin (A) having a cyclic imide group in the molecule, the monomer and the polyisocyanate compound are added stepwise (multistage) to synthesize the isocyanate-terminated oligomer, and the molecular weight is stepwise By making it raise, the water-based polyurethane resin (A) with few dispersion | variation in molecular weight distribution can be obtained.

  A trifunctional or higher polyol compound or polyisocyanate may be used as a raw material for the synthesis of the aqueous polyurethane resin (A), but the resulting aqueous polyurethane resin (A) may be three-dimensional (gelled). As described above, it is preferable to use a diol compound and a diisocyanate compound as synthetic raw materials. The aqueous polyurethane resin (A) synthesized from a diol compound and a diisocyanate compound can easily exhibit excellent gloss and pigment dispersion function.

  In the urethane reaction, a general reaction temperature can be employed, and a reaction temperature of 60 to 100 ° C is appropriate, and 60 to 80 ° C is more appropriate. If the reaction temperature is too high, side reactions such as allophanate bonds occur, and if it is too low, the reaction time becomes longer and the production efficiency is lowered.

  In the urethane reaction, a reaction solvent can be selected from those that do not react with an isocyanate group in the absence of a solvent. When selecting a reaction solvent that can be removed after the reaction, it is preferable to select from among good solvents for polyurethane resins having a boiling point of 70 ° C. or higher and lower than 110 ° C. Specific examples of the reaction solvent include ethyl acetate, methyl ethyl ketone, and acetonitrile.

  In the urethane reaction, the reaction catalyst can be selected from any known urethane reaction catalyst. Typical examples include tin catalysts such as dibutyltin dilaurate and stannous octylate, metal catalysts such as organic titanium and zirconium catalyst, tertiary amines such as triethylamine and tributylamine, triethylenediamine, and 1,8- Mention may be made of amine catalysts such as diazabicyclo [5.4.0] undecene-7 and neutralized salts.

  The aqueous polyurethane resin (A) having a cyclic imide group in the molecule is composed of a diol compound (a1) having a cyclic imide group in the side chain and a cyclic imide mono group with respect to structural units derived from all polyol compounds constituting the polyurethane resin. It is preferable to have a total of 5 to 100 mol% of structural units derived from the all compound (a2), more preferably 10 to 90 mol%, and more preferably 15 to 80 mol%. Is more preferable.

  The aqueous polyurethane resin (A) having a cyclic imide group in the molecule has 0 structural units derived from the polyol compound (a3) having a polar molecular chain with respect to structural units derived from all the polyol compounds constituting the polyurethane resin. It is preferable to have ~ 50 mol%, more preferably 5 to 45 mol%, and even more preferably 10 to 40 mol%.

  The aqueous polyurethane resin (A) having a cyclic imide group in the molecule is a structural unit derived from the polyol compound (a4) having a low polarity molecular chain, with respect to the structural units derived from all the polyol compounds constituting the polyurethane resin. It is preferable to have 0 to 50 mol%, more preferably 5 to 45 mol%, and even more preferably 10 to 40 mol%.

  When a polyurethane resin is prepared using a polyisocyanate compound exceeding bifunctionality, P.I. It is desirable to suppress the gelation by adjusting the molar fraction with reference to J Flory's gelation formula or the like.

  In the water-based polyurethane resin (A) having a cyclic imide group in the molecule, a urethane compound, a structural unit derived from the diol compound (a1) having a cyclic imide group in the side chain, a polyol compound having a polar molecular chain (a3 ) And the content ratio of the structural unit derived from the polyol compound (a4) having a low polar molecular chain can be controlled by adjusting the ratio of each diol compound subjected to the urethane reaction. Since the polyurethane reaction is a sequential reaction, the control of the number of structural units derived from each of the above compounds can be easily performed.

After completion of the urethane reaction, the obtained aqueous polyurethane resin (A) is appropriately phase-shifted into an aqueous medium.
Examples of the aqueous medium include water and water containing water as a main component and a slight amount of an organic solvent added, and water is preferable.
When the aqueous polyurethane resin (A) has a structural unit derived from a tertiary carboxyl group-containing diol compound or the like, a compound serving as a counter ion when phase-converting the aqueous polyurethane resin (A) to an aqueous medium It is preferable to neutralize appropriately.
Examples of the counter ion compound include inorganic alkalis such as sodium hydroxide and potassium hydroxide, quaternary amines such as tetramethylammonium hydride, triethylamine, trimethylamine, N-methylmorpholine, tributylamine, N-methylpyrazine, and methyl. There may be mentioned tertiary amines such as imidazole.

The aqueous polyurethane resin (A) having a cyclic imide group in the molecule has a diol compound (a3) having a polar molecular chain and a low-polar molecular chain with respect to the diol compound (a1) having a cyclic imide group in the side chain. It is desirable to adopt a molecular form of a block copolymer obtained by connecting a diol compound (a4) with a diisocyanate, which is a polyisocyanate compound, and a cyclic imide monool compound (a2) is a polyisocyanate compound at the end of the polyurethane main chain. It is desirable to take the molecular form of a block copolymer linked by diisocyanate. By adopting such a molecular form, the dispersibility of the pigment (B) can be further improved.
Since the polyurethane reaction is a sequential reaction, a polyurethane resin having a block structure can be easily obtained by connecting diol compounds having different polarities with a polyisocyanate compound.

  When the aqueous polyurethane resin (A) having a cyclic imide group in the molecule has a structural unit derived from the diol compound (a1) having a cyclic imide group in the side chain, the cyclic imide group of the diol compound (a1) Is provided in the shape of a comb as a side chain, and it is considered that such a comb-like structure improves the dispersibility of the pigment (B). The polyol compound (a3) having a polar molecular chain and It is considered that the dispersion effect can be further enhanced by connecting molecular chains having different polarities derived from the polyol compound (a4) having a low polar molecular chain in a block manner.

  The aqueous polyurethane resin (A) having a cyclic imide group in the molecule preferably has 0.5 mol or more of cyclic imide groups in 1 kg of the aqueous polyurethane resin (A), and has 1 mol or more. Is more preferable.

The number average molecular weight of the water-based polyurethane resin (A) having a cyclic imide group in the molecule is not particularly limited, but when used for inkjet ink, the number average molecular weight is suitably 1000 to 15000, and 1300 to 1300. 10,000 is more appropriate, and 1600 to 8000 is more appropriate.
Since the polyurethane reaction described above is a sequential reaction, the number average molecular weight of the active energy ray-curable polyurethane resin of the present invention can be easily adjusted by adjusting the amount of each reaction component (monomer).

  The aqueous polyurethane resin (A) having a cyclic imide group in the molecule is obtained by subjecting the diol compound (a1) having a cyclic imide group represented by the above general formula (I) in the side chain to a urethane reaction as a monomer raw material. In this case, the number average molecular weight can be calculated by the following method.

Number average molecular weight of aqueous polyurethane resin (A) = nA ′ + (n + 1) B ′
(Where n is the total number of moles of all diol compounds used as monomers, A ′ is the number average molecular weight of all diol compounds used as monomers, and B ′ is the number average molecular weight of diisocyanate compounds.)

  The aqueous polyurethane resin (A) preferably has an acid value of 20 to 120 KOH mg / g, more preferably 30 to 110 KOH mg / g, and still more preferably 35 to 100 KOH mg / g.

When the acid value of the aqueous polyurethane resin (A) is within the above range, the dispersibility of the pigment (B) in an aqueous medium such as water can be improved.
The acid value can be controlled, for example, by employing a tertiary carboxyl group-containing diol compound as a monomer constituting the aqueous polyurethane resin (A) and adjusting the number of moles thereof.

  The acid value AN of the aqueous polyurethane resin (A) can be calculated by the following method.

(Where a1 is the number of moles of a tertiary carboxyl group-containing diol compound such as dimethylolpropionic acid, A1 is the molecular weight of a tertiary carboxyl group-containing diol compound such as dimethylolpropionic acid, and a2, a3,. The number of moles of other diols, A2, A3... An is the molecular weight of other diols, and b1, b2, b3. Is the molecular weight of the diisocyanate compound.)

The water-based polyurethane resin (A) having a cyclic imide group in the molecule exhibits excellent dispersibility because the cyclic imide group itself is a group having a low-polarity structure part and a high-polarity structure part, and inkjet ink. It is possible to provide a pigment dispersion composition in which a coating film obtained when used in a composition or a coating composition exhibits excellent image density and hiding properties and can exhibit excellent gloss.
Furthermore, the aqueous polyurethane resin (A) is a structural unit derived from the diol compound (a1) having a cyclic imide group represented by the general formula (I) in the side chain, or a cyclic imide monool represented by the general formula (II) Having the structural unit derived from the compound (a2), and having a comb-like structure having a cyclic imide group at the side chain or terminal of the polyurethane resin, the above characteristics can be effectively exhibited. it can.

  The aqueous pigment dispersion composition of the present invention contains the pigment (B) and the dispersant (C) together with the aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule.

Examples of the pigment (B) include insoluble azo pigments, soluble azo pigments, phthalocyanine pigments, quinacridone pigments, perylene pigments, isoindoline pigments, benzimidazolone pigments, pyranthrone pigments, thioindigo pigments, and quinophthalone pigments. Organic pigments can be mentioned, and among these organic pigments, phthalocyanine pigments are preferred.
Examples of the phthalocyanine pigment include phthalocyanine blue and phthalocyanine green, and phthalocyanine blue is preferable.
Specific examples of phthalocyanine blue include C.I. I. And at least one selected from CI Pigment Blue 15, 15: 1, 15: 2, 15: 3, and 15: 6.

The pigment aqueous dispersion composition of the present invention may contain a synergist.
As the synergist, a phthalocyanine-based synergist (a synergist comprising a compound having a phthalocyanine skeleton) is preferable, and a phthalocyanine skeleton such as a phthalocyanine sulfonic acid-based synergist or a phthalocyanine phosphate-based synergist is introduced, and an acid group such as a sulfonic acid group or a phosphate group is introduced. A synergist comprising the above compounds is more preferred.
Specific examples of the phthalocyanine sulfonic acid synergist include Solsperse 12000 manufactured by Lubrizol.
When the aqueous pigment dispersion composition of the present invention contains a synergist, the viscosity of the aqueous dispersion composition can be lowered to improve the dispersibility of the pigment (B) in a solvent (vehicle).

  When the pigment aqueous dispersion composition of the present invention contains a phthalocyanine pigment as the pigment (B) and a phthalocyanine synergist as a synergist, the pigment (B) is dispersed in a solvent such as water by reducing the viscosity in particular. Property can be preferably improved.

  The dispersant (C) is not particularly limited as long as it has an affinity for a solvent such as an aqueous solvent and an affinity for a pigment, and is commercially available, for example, as an aqueous dispersant or a surfactant. Among them, particularly preferred examples include dispersants for aqueous systems such as Solsperse 43000, 44000, 46000 manufactured by Lubrizol, Disperbyk-190, 191, 194, 2010 manufactured by BYK.

  The pigment dispersion composition of the present invention preferably contains 3 to 35% by mass, more preferably 3 to 25% by mass of pigment (B) in 100% by mass of the pigment dispersion composition. It is more preferable that the content is ˜20% by mass.

  The pigment dispersion composition of the present invention comprises 2 to 200 parts by mass of the aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule with respect to 100 parts by mass of the pigment (B) in terms of solid content. It is preferable that 3-150 parts by mass is included, and 5-100 parts by mass is more preferable.

  When the pigment dispersion composition of the present invention includes the synergist, it is preferable to include 1 to 30 parts by mass of the synergist with respect to 100 parts by mass of the pigment (B) in terms of solid content. More preferably, it contains 1 part by weight, more preferably 1-15 parts by weight, and even more preferably 1-10 parts by weight.

  The pigment dispersion composition of the present invention preferably contains 1 to 30 parts by mass, and 1 to 20 parts by mass of the dispersant (C) in terms of solid content with respect to 100 parts by mass of the pigment (B). More preferably, it is more preferably 1 to 10 parts by mass.

  The pigment dispersion composition of the present invention comprises an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, the pigment (B), and the dispersant (C) in the above proportions, thereby providing excellent dispersibility. While exhibiting, the coating film obtained when used in an ink-jet ink composition or a coating composition can exhibit excellent image density and concealment and can exhibit excellent gloss.

The pigment dispersion composition of the present invention comprises an aqueous polyurethane dispersion resin (A) having a cyclic imide group in a molecule, a pigment (B), and a dispersant (C) in a desired content ratio in an aqueous medium. It can be prepared by mixing and dispersing using a dispersion mill or the like.
Examples of the aqueous medium include water and water containing water as a main component and a slight amount of an organic solvent added, and water is preferable.

  The pigment dispersion composition of the present invention may be a coating material premix (mill base) for preparing a coating agent or the like.

  The pigment aqueous dispersion composition of the present invention comprises an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C), thereby providing excellent dispersibility. When used in a water-based ink composition, the resulting coating film can exhibit excellent image density and hiding properties and excellent gloss.

Next, the water-based ink composition of the present invention will be described.
The water-based ink composition of the present invention is characterized by including the pigment aqueous dispersion composition of the present invention.

  Examples of the aqueous ink composition of the present invention include an aqueous inkjet ink composition, an aqueous coating composition, an ultraviolet curable aqueous inkjet ink, an ultraviolet curable aqueous coating, and an ultraviolet curable aqueous coating agent.

  When the water-based ink composition of the present invention is an ink-jet ink composition, the pigment dispersion composition of the present invention, that is, the water-based polyurethane dispersion resin (A) having a cyclic imide group in the molecule, the pigment (B) and the dispersant ( The dispersion composition in which C) is dispersed to a desired content ratio is further stirred as necessary, and the above synergist, any known moisturizer, preservative, emulsifier, pH adjuster, Add additives such as foam coating film surface smoothing agent, water-soluble resin, wax dispersed in water, resin emulsion, etc., stir and adjust the viscosity by adding water or water-soluble organic solvent as necessary Can be manufactured.

  It is also preferable to add a surfactant to uniformly disperse the pigment. As the surfactant, any of an anionic surfactant, a nonionic surfactant, and a cationic surfactant may be used. it can. For example, as anionic surfactant, fatty acid salt, alkyl sulfate ester salt, alkylaryl sulfonate, etc., and as nonionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, etc., cationic surfactant Examples of the agent include alkylamine salts and quaternary ammonium salts.

After adding each of the above components and stirring, it is preferable to appropriately filter by any known filtration method.
For example, when a large undispersed lump or coarse particle is present in the pigment slurry, it is preferably removed by a method such as centrifugation or filtration, and the aqueous pigment obtained by removing the undispersed lump or coarse particle The particle size distribution of the dispersion composition can be controlled, and the occurrence of nozzle clogging during printing can be suppressed when the aqueous pigment dispersion composition is used in an ink composition for an ink jet printer.

  In addition, the pigment slurry may be appropriately neutralized, and when the slurry is neutralized, it is preferable to remove salts (oxide of neutralizing agent) generated by the neutralization treatment, and the ultrafiltration membrane It is preferable to remove by a separation membrane such as (UF), reverse osmosis membrane (RO), and electrodialysis membrane.

  The pigment concentration of the water-based inkjet ink composition can be the same as that of a known inkjet ink composition, and varies depending on the type of pigment, but the pigment concentration is suitably about 2 to 15% by mass. is there.

  Since the water-based ink composition of the present invention contains the pigment aqueous dispersion composition of the present invention, the resulting coating film exhibits excellent image density and hiding properties and excellent gloss.

  EXAMPLES Next, although an Example is given and this invention is demonstrated more concretely, this is only an illustration and does not restrict | limit this invention.

<Synthesis of aqueous polyurethane resin (A) having a cyclic imide group in the molecule>
(1) Synthesis of Diol Compound (a1) Having Cyclic Imide Group in Side Chain Stirring, 92 mass of 1-aminopropanediol manufactured by Daicel Chemical Industries, Ltd. in a flask set with a dry nitrogen blowing tube and a condenser tube with a condensed water trap Part, 79.4 parts by mass of toluene were added and stirred, and further 164 parts by mass of Rikacid MH-700 [4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30] manufactured by Shin Nippon Chemical Co., Ltd. was divided into 5 parts. The temperature was added while cooling so that the temperature did not exceed 90 ° C.
After charging the entire amount of Ricacid MH-700, the mixture was kept at 90 to 95 ° C. for 15 minutes, and 0.5 parts by mass of tetraisopropyl titanium was added. Next, the reaction temperature was gradually increased, and dehydration reaction was performed at a toluene reflux temperature of 110 to 115 ° C.
When the dehydration amount reaches 18 parts by mass, the acid value is measured and reacted until the acid value becomes 1.5 or lower (equivalent to a reaction rate of 99%) to obtain a diol compound (a1) having a cyclic imide group in the side chain. Obtained. Further, the reaction solvent was distilled off under reduced pressure at 70 ° C., and the solvent was removed until the solid content reached 99% or more.

(2) Synthesis of Cyclic Imidomonool Compound (a2) In a flask in which a stirring tube, a dry nitrogen blowing tube and a condenser tube with a condensed water trap were set, 92.9 parts by mass of Guangei Chemical Industry Co., Ltd. 3-aminopropanol, 74 of toluene Then, 4 parts by mass was added, and 148 parts by mass of phthalic anhydride was further divided into 5 parts, and then charged while cooling so that the temperature did not exceed 90 ° C.
After the whole amount of phthalic anhydride was charged, the mixture was kept at 90 to 95 ° C. for 15 minutes, and 0.5 parts by mass of tetraisopropyl titanium was added. Next, the reaction temperature was gradually increased, and dehydration reaction was performed at a toluene reflux temperature of 110 to 115 ° C.
When the dehydration amount reached 18 parts by mass, the acid value was measured and reacted until the acid value became 1.7 or less (equivalent to a reaction rate of 99%) to obtain a cyclic imide monool compound (a2). Further, the reaction solvent was distilled off under reduced pressure at 70 ° C., and the solvent was removed until the solid content reached 99% or more.

(3) Synthesis of Isocyanate-Terminated Aqueous Polyurethane Resin (A) Having Cyclic Imido Group in the Molecule 150 parts by mass of ethyl acetate and 34 dimethylolbutanoic acid in a flask equipped with stirring, a nitrogen gas blowing tube and a ball cooling tube 5 parts by mass, 59.5 parts by mass of Dismodule I (isophorone diisocyanate) manufactured by Sumika Bayer Urethane Co., Ltd. and 97.3 parts by mass of Dismodule W (hydrogenated MDI) manufactured by Sumika Bayer Urethane Co., Ltd. After reacting for a while, 40.3 parts by mass of Toyokuni Oil Castor Oil ELA-DR, 76.8 parts by mass of PTXG1800 (number average molecular weight 1791.8) manufactured by Asahi Kasei Fibers Co., Ltd. obtained in the above (1) 41.4 parts by mass of diol compound (a1) having an imide group in the side chain and 116 parts by mass of ethyl acetate were added and reacted at 83 ° C. for 5 hours ( The isocyanate group mass% of the reaction solution at this time was 1.7 mass%), and then 50.2 parts by mass of the cyclic imide monool compound (a2) obtained in the above (2) and 134 parts by mass of ethyl acetate were added to add 83. The mixture was further reacted at 5 ° C. for 5 hours (NCO% at this time was 0.01%), cooled to 35 ° C., and further added with 41.2 parts by mass of triethylamine and stirred for 30 minutes to form side chains and terminals. A liquid containing an isocyanate-terminated aqueous polyurethane resin (A) having a cyclic imide group (hereinafter referred to as “polyurethane resin 1”) was obtained.
The resulting liquid containing polyurethane resin 1 has a non-volatile content of 50.0% by mass, a Gardner cell viscosity of Z3 ² -4, and polyurethane resin 1 is a number determined by GPC measurement (polystyrene conversion gel permeation chromatograph). The average molecular weight was 4080, and the weight average molecular weight was 13,100.

Example 1 Preparation of Phthalocyanine Pigment Aqueous Dispersion α 20 parts by mass of the polyurethane resin 1 (nonvolatile content 50.0% by mass), 20 parts by mass of Fastgen Blue FA5380 (copper phthalocyanine) manufactured by DIC, manufactured by BYK Disperbyk-192 1.2 parts by mass, BYK Disperbyk-198 4.8 parts by mass, Nissin Chemical Industry Olphine AK02 0.8 parts by mass, ion-exchanged water 53.2 parts by mass in a mayonnaise bottle After adding 150 parts by weight of 0.6 mmφ zirconia beads and dispersing for 3 hours with a paint shaker manufactured by Asada Tekko, the beads and the dispersion were separated by filtration, and the ethyl acetate (polyurethane resin reaction solvent) in the dispersion was depressurized. Distillation and distillation gave an aqueous phthalocyanine pigment dispersion α.
The obtained aqueous phthalocyanine pigment dispersion α has a non-volatile content of 27.9% by mass, a viscosity of 5.7 mPa · s, and a phthalocyanine concentration of 15.5% by mass. The polyurethane resin 1 contained 50 parts by mass and the dispersant contained 24 parts by mass with respect to 100 parts by mass of the phthalocyanine-based pigment.

(Example 2) Preparation of Phthalocyanine Pigment Aqueous Dispersion β 20 parts by mass of the above polyurethane resin 1 (nonvolatile content 50.0% by mass), 20 parts by mass of Fastgen Blue FA5380 (copper phthalocyanine) manufactured by DIC, Lubrizol Corporation 2 parts by mass of Solsperse-46000 manufactured by Lubrizol, 0.5 part by mass of Solsperse-12000 manufactured by Lubrizol, 0.8 part by mass of Orphin AK02 manufactured by Nissin Chemical Industry Co., Ltd., and 56.7 parts of ion-exchanged water are put in a mayonnaise bottle. After adding 150 parts by weight of 0.6 mmφ zirconia beads and dispersing for 3 hours with a paint shaker manufactured by Asada Tekko, the beads and the dispersion were separated by filtration, and ethyl acetate (polyurethane resin reaction solvent) in the dispersion was distilled under reduced pressure. Then, phthalocyanine pigment aqueous dispersion β was obtained by distillation.
The obtained aqueous phthalocyanine pigment dispersion β had a non-volatile content of 26.5% by mass, a viscosity of 2.92 mPa · s, and a phthalocyanine concentration of 16.3% by mass. The polyurethane resin 1 contained 50 parts by mass, the synergist 2.5 parts by mass, and the dispersant 10 parts by mass with respect to 100 parts by mass of the phthalocyanine pigment contained in.

Comparative Example 1 Preparation of Comparative Phthalocyanine Pigment Aqueous Dispersion γ As a comparative aqueous polyurethane resin, DIC polyurethane resin dispersion hydran HW-163 (non-volatile content: 33 mass%, viscosity: 34 mPa · s) is 30. 3 parts by mass, 20 parts by mass of Fastgen Blue FA5380 (copper phthalocyanine) manufactured by DIC, 2 parts by mass of Solsperse-46000 manufactured by Lubrizol, 0.5 parts by mass of Solsperse-12000 manufactured by Lubrizol, manufactured by Nisshin Chemical Industry Add 0.8 parts by mass of Olfine AK02 and 46.4 parts of ion-exchanged water into a mayonnaise bottle, add 150 parts by mass of 0.6 mmφ zirconia beads, and disperse with a paint shaker manufactured by Asada Iron Works for 3 hours, and then disperse with beads. The liquid was filtered off, and the content of nonvolatile content was 27. Was adjusted to the amount%, viscosity was obtained 22.6mPa · s, compared phthalocyanine phthalocyanine concentration of 16.6 wt% pigment aqueous dispersion gamma.

(Example 3) Preparation of liquid ink 1 Liquid ink 1 was obtained by mixing 32.3 parts by mass of the aqueous phthalocyanine pigment dispersion α obtained in Example 1 and 67.7 parts by mass of ion-exchanged water. It was.

(Example 4) Preparation of liquid ink 2 Liquid ink 2 was obtained by mixing 30.7 parts by mass of the aqueous phthalocyanine pigment dispersion β obtained in Example 2 and 69.3 parts by mass of ion-exchanged water. It was.

(Example 5) Preparation of liquid ink 3 30.7 parts by mass of the aqueous phthalocyanine pigment dispersion β obtained in Example 2 and polyurethane resin dispersion hydran HW-163 (nonvolatile content: 33% by mass) manufactured by DIC The liquid ink 3 was obtained by mixing 3.0 parts by mass with a viscosity of 34 mPa · s) and 66.3 parts by mass of ion-exchanged water.

Comparative Example 2 Preparation of Comparative Liquid Ink 1 By mixing 30.1 parts by mass of the comparative phthalocyanine pigment aqueous dispersion γ obtained in Comparative Example 1 with 69.9 parts by mass of ion-exchanged water, a comparative liquid ink is prepared. 1 was obtained.

(Comparative Example 3) Preparation of Comparative Liquid Ink 2 30.1 parts by mass of the comparative phthalocyanine pigment aqueous dispersion γ obtained in Comparative Example 1 and polyurethane resin dispersion hydran HW-163 (non-volatile content ratio 33 manufactured by DIC) Comparative liquid ink 2 was obtained by mixing 3.0 parts by mass and 66.8 parts by mass of ion-exchanged water (mass%, viscosity 34 mPa · s).

(Comparative Example 4) Preparation of Comparative Liquid Ink 3 As a commercially available cyan inkjet ink, cyan ink was taken out from ECI-E47C cartridge manufactured by Ecolica Co., Ltd. and used as comparative liquid ink 3.

  The compositions of the liquid inks 1 to 3 are shown in Table 1, and the compositions of the comparative liquid inks 1 to 3 are shown in Table 2.

  The gloss, image density (OD), and dispersibility of the liquid inks 1 to 3 and the comparative liquid inks 1 to 3 were evaluated by the following methods. Since the dispersibility of each liquid ink is related to the hiding power and coloring power of the pigment, the hiding power and coloring power of the pigment can also be evaluated by evaluating the dispersibility of the liquid ink. These evaluation results are shown in Table 3.

<Glossy evaluation>
For each ink, draw down rod no. 6. After applying to 75cm thick polyester film manufactured by Toray Industries Co., Ltd. and applying it to ACL75TACX manufactured by Panac Co., Ltd., it was dried for 5 minutes with a blow dryer at 100 ° C. Measurement was performed with a gloss meter (product name: micro-gloss 60 °) manufactured by BYK-Gardner GmbH, and evaluation was performed according to the following criteria.
○: 60 ° gloss measurement value is 80 or more Δ: 60 ° gloss measurement value is 70 to 79
×: 60 ° gloss measurement value is 60 to 69

<Image density (OD) evaluation>
Draw down rod no. After applying to plain paper in No. 6, the reflection optical density (OD value) of the obtained coating film, which was dried with a blow dryer at 100 ° C. for 5 minutes, was measured by X-rite color difference meter X-Rite-528. And evaluated according to the following criteria.
○: OD value 1.0 or more
×: OD value less than 1.0

<Evaluation of dispersibility>
Using a dynamic light scattering particle size measuring machine (UPA-EX150 manufactured by Microtrack), the volume-based cumulative particle size distribution of each ink was measured and evaluated according to the following criteria.
○: The particle size distribution is a normal distribution, and the particle size (average particle size D50) of 50% in terms of the integrated particle size is 100 to 120 nm.
(Triangle | delta): A particle size distribution is a normal distribution, and the particle size (average particle size D50) of 50% by integrated particle size is more than 120 nm and less than 150 nm.
X: 50% of the average particle size (average particle size D50) is 150 nm or more, or the particle size distribution is not a normal distribution but has 2 or more peaks.

From Table 3, liquid inks 1 to 3 containing the pigment aqueous dispersion composition according to the present invention have excellent gloss and image density (OD), and excellent pigment dispersibility. It can also be seen that, since the dispersibility of the pigment is excellent, the pigment has excellent concealability and colorability.
On the other hand, the comparative liquid inks 1 to 3 do not contain the pigment aqueous dispersion composition according to the present invention, so that the resulting coating film has poor gloss (comparative liquid inks 1 to 3), image density ( OD) is not sufficient (Comparative Liquid Ink 3), the dispersibility of the pigment is insufficient, and the pigment is inferior in concealability and colorability (Comparative Liquid Inks 1-2).

  ADVANTAGE OF THE INVENTION According to this invention, while being able to provide the pigment aqueous dispersion composition which exhibits the outstanding dispersibility, the obtained coating film shows the outstanding image density and concealment property, and also shows the outstanding glossiness A composition can be provided.

Claims (6)

  A pigment aqueous dispersion composition comprising an aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule, a pigment (B), and a dispersant (C). The aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule is represented by the following general formula (I)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, which may be the same or different, and R ¹ And R ² may combine to form a cyclic structure, wherein R ³ is an alkylene group having 1 to 22 carbon atoms, and R ⁴ is an alkylene group having 0 to 22 carbon atoms. The aqueous pigment dispersion composition according to claim 1, which is obtained by subjecting a diol compound (a1) having an imide group to a side chain to a urethane reaction as a monomer raw material. The aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule is further represented by the following general formula (II)

(However, R ¹ and R ² are each a hydrogen atom or a linear or branched hydrocarbon group having 1 to 6 carbon atoms, which may be the same or different, and R ¹ And R ² may be bonded to form a cyclic structure, and R ³ is an alkylene group having 1 to 22 carbon atoms.) The aqueous pigment dispersion composition according to claim 2, which is obtained by subjecting a side chain or a terminal of a chain to urethane reaction.   The pigment dispersion composition according to any one of claims 1 to 3, wherein the pigment (B) is a phthalocyanine pigment. While containing 3 to 35% by mass of the pigment (B),
In terms of solid content, 2 to 200 parts by mass of the aqueous polyurethane dispersion resin (A) having a cyclic imide group in the molecule and 1 to 30 parts by mass of the dispersant (C) with respect to 100 parts by mass of the pigment (B). The pigment aqueous dispersion composition according to any one of claims 1 to 4, comprising a part.   A water-based ink composition comprising the pigment aqueous dispersion composition according to any one of claims 1 to 5.